Publications

Abstract

People routinely point to empty space when referring to absent entities. These points to "nothing" are meaningful because they direct attention to places that stand in for specific entities. Typically, the meaning of places in terms of absent referents is established through preceding discourse and accompanying language. However, it is unknown whether nonlinguistic actions can establish locations as meaningful places, and whether infants have the capacity to represent a place as standing in for an object. In a novel eye-tracking paradigm, 18-month-olds watched objects being placed in specific locations. Then, the objects disappeared and a point directed infants' attention to an emptied place. The point to the empty place primed infants in a subsequent scene (in which the objects appeared at novel locations) to look more to the object belonging to the indicated place than to a distracter referent. The place-object expectations were strong enough to interfere when reversing the place-object associations. Findings show that infants comprehend nonlinguistic reference to absent entities, which reveals an ontogenetic early, nonverbal understanding of places as representations of absent objects

Abstract

Different linguistic modalities (speech or sign) offer different levels at which signals can iconically represent the world. One hypothesis argues that this iconicity has an effect on how linguistic structure emerges. However, exactly how and why these effects might come about is in need of empirical investigation. In this contribution, we present a signal creation experiment in which both the signalling space and the meaning space are manipulated so that different levels and types of iconicity are available between the signals and meanings. Signals are produced using an infrared sensor that detects the hand position of participants to generate auditory feedback. We find evidence that iconicity may be maladaptive for the discrimination of created signals. Further, we implemented Hidden Markov Models to characterise the structure within signals, which was also used to inform a metric for iconicity.

Abstract

This review covers experimental approaches to sound-symbolism—from infants to adults, and from Sapir’s foundational studies to twenty-first century product naming. It synthesizes recent behavioral, developmental, and neuroimaging work into a systematic overview of the cross-modal correspondences that underpin iconic links between form and meaning. It also identifies open questions and opportunities, showing how the future course of experimental iconicity research can benefit from an integrated interdisciplinary perspective. Combining insights from psychology and neuroscience with evidence from natural languages provides us with opportunities for the experimental investigation of the role of sound-symbolism in language learning, language processing, and communication. The review finishes by describing how hypothesis-testing and model-building will help contribute to a cumulative science of sound-symbolism in human language.

Abstract

Sound-symbolism, or the direct link between sound and meaning, is typologically and behaviorally attested across languages. However, neuroimaging research has mostly focused on artificial non-words or individual segments, which do not represent sound-symbolism in natural language. We used EEG to compare Japanese ideophones, which are phonologically distinctive sound-symbolic lexical words, and arbitrary adverbs during a sentence reading task. Ideophones elicit a larger visual P2 response and a sustained late positive complex in comparison to arbitrary adverbs. These results and previous literature suggest that the larger P2 may indicate the integration of sound and sensory information by association in response to the distinctive phonology of ideophones. The late positive complex may reflect the facilitated lexical retrieval of ideophones in comparison to arbitrary words. This account provides new evidence that ideophones exhibit similar cross-modal correspondences to those which have been proposed for non-words and individual sounds, and that these effects are detectable in natural language.

Abstract

* These authors contributed equally/shared first author
Deep convolutional neural networks (DCNNs) are able to partially predict brain activity during object categorization tasks, but factors contributing to this predictive power are not fully understood. Our study aimed to investigate the factors contributing to the predictive power of DCNNs in object categorization tasks. We compared the activity of four DCNN architectures with EEG recordings obtained from 62 human participants during an object categorization task. Previous physiological studies on object categorization have highlighted the importance of figure-ground segregation—the ability to distinguish objects from their backgrounds. Therefore, we investigated whether figure-ground segregation could explain the predictive power of DCNNs. Using a stimulus set consisting of identical target objects embedded in different backgrounds, we examined the influence of object background versus object category within both EEG and DCNN activity. Crucially, the recombination of naturalistic objects and experimentally controlled backgrounds creates a challenging and naturalistic task, while retaining experimental control. Our results showed that early EEG activity (< 100 msec) and early DCNN layers represent object background rather than object category. We also found that the ability of DCNNs to predict EEG activity is primarily influenced by how both systems process object backgrounds, rather than object categories. We demonstrated the role of figure-ground segregation as a potential prerequisite for recognition of object features, by contrasting the activations of trained and untrained (i.e., random weights) DCNNs. These findings suggest that both human visual cortex and DCNNs prioritize the segregation of object backgrounds and target objects to perform object categorization. Altogether, our study provides new insights into the mechanisms underlying object categorization as we demonstrated that both human visual cortex and DCNNs care deeply about object background.

Abstract

This study aims to advance our understanding of the nature and source(s) of individual differences in pragmatic language behavior over the adult lifespan. Across four story continuation experiments, we probed adults’ (N = 496 participants, ages 18–82) choice of referential forms (i.e., names vs. pronouns to refer to the main character). Our manipulations were based on Fossard et al.’s (2018) scale of referential complexity which varies according to the visual properties of the scene: low complexity (one character), intermediate complexity (two characters of different genders), and high complexity (two characters of the same gender). Since pronouns signal topic continuity (i.e., that the discourse will continue to be about the same referent), the use of pronouns is expected to decrease as referential complexity increases. The choice of names versus pronouns, therefore, provides insight into participants’ perception of the topicality of a referent, and whether that varies by age and cognitive capacity. In Experiment 1, we used the scale to test the association between referential choice, aging, and cognition, identifying a link between older adults’ switching skills and optimal referential choice. In Experiments 2–4, we tested novel manipulations that could impact the scale and found both the timing of a competitor referent’s presence and emphasis placed on competitors modulated referential choice, leading us to refine the scale for future use. Collectively, Experiments 1–4 highlight what type of contextual information is prioritized at different ages, revealing older adults’ preserved sensitivity to (visual) scene complexity but reduced sensitivity to linguistic prominence cues, compared to younger adults.

Abstract

This study investigated how adults over the lifespan flexibly adapt their use of prosocial speech acts when conveying bad news to communicative partners. Experiment 1a (N = 100 Scottish adults aged 18–72 years) assessed whether participants’ use of prosocial speech acts varied according to audience design considerations (i.e., whether or not the recipient of the news was directly affected). Experiment 1b (N = 100 Scottish adults aged 19–70 years) assessed whether participants adjusted for whether the bad news was more or less severe (an index of general knowledge). Younger adults displayed more flexible adaptation to the recipient manipulation, while no age differences were found for severity. These findings are consistent with prior work showing age-related decline in audience design but not in the use of general knowledge during language production. Experiment 2 further probed younger adults (N = 40, Scottish, aged 18–37 years) and older adults’ (N = 40, Scottish, aged 70–89 years) prosocial linguistic behavior by investigating whether health (vs. nonhealth-related) matters would affect responses. While older adults used prosocial speech acts to a greater extent than younger adults, they did not distinguish between conditions. Our results suggest that prosocial linguistic behavior is likely influenced by a combination of differences in audience design and communicative styles at different ages. Collectively, these findings highlight the importance of situating prosocial speech acts within the pragmatics and aging literature, allowing us to uncover the factors modulating prosocial linguistic behavior at different developmental stages.

Abstract

People are optimistic about their prospects relative to others. However, existing studies can be difficult to interpret because outcomes are not zero-sum. For example, one person avoiding cancer does not necessitate that another person develops cancer. Ideally, optimism bias would be evaluated within a closed formal system to establish with certainty the extent of the bias and the associated environmental factors, such that optimism bias is demonstrated when a population is internally inconsistent. Accordingly, we asked NFL fans to predict how many games teams they liked and disliked would win in the 2015 season. Fans, like ESPN reporters assigned to cover a team, were overly optimistic about their team’s prospects. The opposite pattern was found for teams that fans disliked. Optimism may flourish because year-to-year team results are marked by auto-correlation and regression to the group mean (i.e., good teams stay good, but bad teams improve).

Abstract

FOXP1 (forkhead box protein P1) is a transcription factor involved in the development of several tissues, including the brain. An emerging phenotype of patients with protein-disrupting FOXP1 variants includes global developmental delay, intellectual disability and mild to severe speech/language deficits. We report on a female child with a history of severe hypotonia, autism spectrum disorder and mild intellectual disability with severe speech/language impairment. Clinical exome sequencing identified a heterozygous de novo FOXP1 variant c.1267_1268delGT (p.V423Hfs*37). Functional analyses using cellular models show that the variant disrupts multiple aspects of FOXP1 activity, including subcellular localization and transcriptional repression properties. Our findings highlight the importance of performing functional characterization to help uncover the biological significance of variants identified by genomics approaches, thereby providing insight into pathways underlying complex neurodevelopmental disorders. Moreover, our data support the hypothesis that de novo variants represent significant causal factors in severe sporadic disorders and extend the phenotype seen in individuals with FOXP1 haploinsufficiency

Abstract

The lack of diversity in the language sciences has increasingly been criticized as it holds the potential for producing flawed theories. Research on (i) geographically diverse language communities and (ii) on sign languages is necessary to corroborate, sharpen, and extend existing theories. This study contributes a case study of adapting a well-established paradigm to study the acquisition of sign phonology in Kata Kolok, a sign language of rural Bali, Indonesia. We conducted an experiment modeled after the familiarization paradigm with child signers of Kata Kolok. Traditional analyses of looking time did not yield significant differences between signing and non-signing children. Yet, additional behavioral analyses (attention, eye contact, hand behavior) suggest that children who are signers and those who are non-signers, as well as those who are hearing and those who are deaf, interact differently with the task. This study suggests limitations of the paradigm due to the ecology of sign languages and the sociocultural characteristics of the sample, calling for a mixed-methods approach. Ultimately, this paper aims to elucidate the diversity of adaptations necessary for experimental design, procedure, and analysis, and to offer a critical reflection on the contribution of similar efforts and the diversification of the field.

Abstract

Minimal expressions are at the heart of interaction: Interjections like "Huh?" and "Mhm" keep conversations flowing by establishing and reinforcing intersubjectivity among interlocutors. Crosslinguistic research has identified that similar interactional pressures can yield structurally similar words (e.g., to initiate repair across languages). While crosslinguistic comparisons that include signed languages remain uncommon, recent work has revealed similarities in discourse management strategies among signers and speakers that share much of their cultural background. This study contributes a crossmodal comparison of repair initiators and continuers in speakers of English and signers of British Sign Language (BSL). We combine qualitative and quantitative analyses of data from sixteen English speakers and sixteen BSL signers, resulting in the following: First, the interactional infrastructure drawn upon by speakers and signers overwhelmingly relies on behaviors of the head, face, and body; these are used alone or sometimes in combination with verbal elements (i.e., spoken words or manual signs), while verbal strategies alone are rare. Second, discourse management strategies are remarkably similar in form across the two languages: A held eye gaze or freeze-look is the predominant repair initiator and head nodding the main continuer. These results suggest a modality-agnostic preference for visual strategies that do not occupy the primary articulators, one that we propose is founded in recipiency; people maintain the flow of communication following principles of minimal effort and minimal interruption.

Abstract

Spoken language comprehension requires abstraction of linguistic information from speech, but the interaction between auditory and linguistic processing of speech remains poorly understood. Here, we investigate the nature of this abstraction using neural responses recorded intracranially while participants listened to conversational English speech. Capitalizing on multiple, language-specific patterns where phonological and acoustic information diverge, we demonstrate the causal efficacy of the phoneme as a unit of analysis and dissociate the unique contributions of phonemic and spectrographic information to neural responses. Quantitive higher-order response models also reveal that unique contributions of phonological information are carried in the covariance structure of the stimulus-response relationship. This suggests that linguistic abstraction is shaped by neurobiological mechanisms that involve integration across multiple spectro-temporal features and prior phonological information. These results link speech acoustics to phonology and morphosyntax, substantiating predictions about abstractness in linguistic theory and providing evidence for the acoustic features that support that abstraction.

Abstract

According to widespread opinion, the meaning of body part terms is determined by salient discontinuities in the visual image; such that hands, feet, arms, and legs, are natural parts. If so, one would expect these parts to have distinct names which correspond in meaning across languages. To test this proposal, we compared three unrelated languages—Dutch, Japanese, and Indonesian—and found both naming systems and boundaries of even basic body part terms display variation across languages. Bottom-up cues alone cannot explain natural language semantic systems; there simply is not a one-to-one mapping of the body semantic system to the body structural description. Although body parts are flexibly construed across languages, body parts semantics are, nevertheless, constrained by non-linguistic representations in the body structural description, suggesting these are necessary, although not sufficient, in accounting for aspects of the body lexicon.

Abstract

The lexicon is central to the concerns of disparate disciplines and has correspondingly elicited conflicting proposals about some of its foundational properties. Some suppose that word meanings and their associated concepts are largely universal, while others note that local cultural interests infiltrate every category in the lexicon. This chapter reviews research in two semantic domains—perception and the body—in order to illustrate crosslinguistic similarities and differences in semantic fields. Data is considered from a wide array of languages, especially those from small-scale indigenous communities which are often overlooked. In every lexical field we find considerable variation across cultures, raising the question of where this variation comes from. Is it the result of different ecological or environmental niches, cultural practices, or accidents of historical pasts? Current evidence suggests that diverse pressures differentially shape lexical fields.

Abstract

In each semantic domain studied to date, there is considerable variation in how meanings are expressed across languages. But are some semantic domains more likely to show variation than others? Is the domain of space more or less variable in its expression than other semantic domains, such as containers, body parts, or colours? According to many linguists, the meanings expressed in grammaticised expressions, such as (spatial) adpositions, are more likely to be similar across languages than meanings expressed in open class lexical items. On the other hand, some psychologists predict there ought to be more variation across languages in the meanings of adpositions, than in the meanings of nouns. This is because relational categories, such as those expressed as adpositions, are said to be constructed by language; whereas object categories expressed as nouns are predicted to be “given by the world”. We tested these hypotheses by comparing the semantic systems of closely related languages. Previous cross-linguistic studies emphasise the importance of studying diverse languages, but we argue that a focus on closely related languages is advantageous because domains can be compared in a culturally- and historically-informed manner. Thus we collected data from 12 Germanic languages. Naming data were collected from at least 20 speakers of each language for containers, body-parts, colours, and spatial relations. We found the semantic domains of colour and body-parts were the most similar across languages. Containers showed some variation, but spatial relations expressed in adpositions showed the most variation. The results are inconsistent with the view expressed by most linguists. Instead, we find meanings expressed in grammaticised meanings are more variable than meanings in open class lexical items.

Abstract

Concepts are so fundamental to human cognition that Fodor declared the heart of a cognitive science to be its theory of concepts. To study concepts, though, cognitive scientists need to be able to identify some. The prevailing assumption has been that they are revealed by words such as triangle, table, and robin. But languages vary dramatically in how they carve up the world with names. Either ordinary concepts must be heavily language dependent, or names cannot be a direct route to concepts. We asked speakers of English, Dutch, Spanish, and Japanese to name a set of 36 video clips of human locomotion and to judge the similarities among them. We investigated what name inventories, name extensions, scaling solutions on name similarity, and scaling solutions on nonlinguistic similarity from the groups, individually and together, suggest about the underlying concepts. Aggregated naming data and similarity solutions converged on results distinct from individual languages.

Abstract

Practices of other initiated repair deal with problems of hearing or understanding what another person has said in the fast-moving turn-by-turn flow of conversation. As such, other-initiated repair plays a fundamental role in the maintenance of intersubjectivity in social interaction. This study finds and analyses a special type of other initiated repair that is used in turn-by-turn conversation in a sign language: Argentine Sign Language (Lengua de Sehas Argentina or LSA). We describe a type of response termed a "freeze-look,' which occurs when a person has just been asked a direct question: instead of answering the question in the next turn position, the person holds still while looking directly at the questioner. In these cases it is clear that the person is aware of having just been addressed and is not otherwise accounting for their delay in responding (e.g., by displaying a "thinking" face or hesitation, etc.). We find that this behavior functions as a way for an addressee to initiate repair by the person who asked the question. The "freeze-look" results in the questioner "re-doing" their action of asking a question, for example by repeating or rephrasing it Thus, we argue that the "freeze-look" is a practice for other-initiation of repair. In addition, we argue that it is an "off-record" practice, thus contrasting with known on record practices such as saying "Huh?" or equivalents. The findings aim to contribute to research on human understanding in everyday turn-by-turn conversation by looking at an understudied sign language, with possible implications for our understanding of visual bodily communication in spoken languages as wel

Abstract

The effect of stimulation history on the perception of a current event can yield two opposite effects, namely: adaptation or hysteresis. The perception of the current event thus goes in the opposite or in the same direction as prior stimulation, respectively. In audiovisual (AV) synchrony perception, adaptation effects have primarily been reported. Here, we tested if perceptual hysteresis could also be observed over adaptation in AV timing perception by varying different experimental conditions. Participants were asked to judge the synchrony of the last (test) stimulus of an AV sequence with either constant or gradually changing AV intervals (constant and dynamic condition, respectively). The onset timing of the test stimulus could be cued or not (prospective vs. retrospective condition, respectively). We observed hysteretic effects for AV synchrony judgments in the retrospective condition that were independent of the constant or dynamic nature of the adapted stimuli; these effects disappeared in the prospective condition. The present findings suggest that knowing when to estimate a stimulus property has a crucial impact on perceptual simultaneity judgments. Our results extend beyond AV timing perception, and have strong implications regarding the comparative study of hysteresis and adaptation phenomena.

Abstract

Information structure is a subfield of linguistic research dealing with the ways speakers encode instructions to the hearer on how to process the message relative to their temporary mental states. To this end, sentences are segmented into parts conveying known and yet-unknown information, usually labeled ‘topic’ and ‘focus.’ Many languages have developed specialized grammatical and lexical means of indicating this segmentation.

Abstract

Classical galactosaemia (CG) is a hereditary disease in galactose metabolism that despite dietary treatment is characterized by a wide range of cognitive deficits, among which is language production. CG brain functioning has been studied with several neuroimaging techniques, which revealed both structural and functional atypicalities. In the present study, for the first time, we compared the oscillatory dynamics, especially the power spectrum and time–frequency representations (TFR), in the electroencephalography (EEG) of CG patients and healthy controls while they were performing a language production task. Twenty-one CG patients and 19 healthy controls described animated scenes, either in full sentences or in words, indicating two levels of complexity in syntactic planning. Based on previous work on the P300 event related potential (ERP) and its relation with theta frequency, we hypothesized that the oscillatory activity of patients and controls would differ in theta power and TFR. With regard to behavior, reaction times showed that patients are slower, reflecting the language deficit. In the power spectrum, we observed significant higher power in patients in delta (1–3 Hz), theta (4–7 Hz), beta (15–30 Hz) and gamma (30–70 Hz) frequencies, but not in alpha (8–12 Hz), suggesting an atypical oscillatory profile. The time-frequency analysis revealed significantly weaker event-related theta synchronization (ERS) and alpha desynchronization (ERD) in patients in the sentence condition. The data support the hypothesis that CG language difficulties relate to theta–alpha brain oscillations.

Abstract

Recent work has claimed that (non-tonal) phonological patterns are subregular (Heinz 2011a,b, 2018; Heinz and Idsardi 2013), occupying a delimited proper subregion of the regular functions—the weakly deterministic (WD) functions (Heinz and Lai 2013; Jardine 2016). Whether or not it is correct (McCollum et al. 2020a), this claim can only be properly assessed given a complete and accurate definition of WD functions. We propose such a definition in this article, patching unintended holes in Heinz and Lai’s (2013) original definition that we argue have led to the incorrect classification of some phonological patterns as WD. We start from the observation that WD patterns share a property that we call unbounded semiambience, modeled after the analogous observation by Jardine (2016) about non-deterministic (ND) patterns and their unbounded circumambience. Both ND and WD functions can be broken down into compositions of deterministic (subsequential) functions (Elgot and Mezei 1965; Heinz and Lai 2013) that read an input string from opposite directions; we show that WD functions are those for which these deterministic composands do not interact in a way that is familiar from the theoretical phonology literature. To underscore how this concept of interaction neatly separates the WD class of functions from the strictly more expressive ND class, we provide analyses of the vowel harmony patterns of two Eastern Nilotic languages, Maasai and Turkana, using bimachines, an automaton type that represents unbounded bidirectional dependencies explicitly. These analyses make clear that there is interaction between deterministic composands when (and only when) the output of a given input element of a string is simultaneously dependent on information from both the left and the right: ND functions are those that involve interaction, while WD functions are those that do not.

Abstract

This paper presents a succinct reconstruction of the segmental phonology of Proto-Maweti-Guarani, the hypothetical protolanguage from which modern Mawe, Aweti and the Tupi-Guarani branches of the Tupi linguistic family have evolved. Based on about 300 cognate sets from the authors' field data (for Mawe and Aweti) and from Mello's reconstruction (2000) for Proto-Tupi-Guarani (with additional information from other works; and with a few changes concerning certain doubtful features, such as the status of stem-final lenis consonants ∗r and ∗β, and the distinction of ∗c and ∗č), the consonants and vowels of Proto-Maweti-Guarani were reconstructed with the help of the traditional historical-comparative method. The development of the reconstructed segments is then traced from the protolanguage to each of the modern branches. A comparison with other claims made about Proto-Maweti-Guarani is given in the conclusion

Abstract

Scientific convergence is a phenomenon where the distance between hitherto distinct scientific fields narrows and the fields gradually overlap over time. It is creating important potential for research, development, and innovation. Although scientific convergence is crucial for the development of radically new technology, the identification of emerging scientific convergence is particularly difficult since the underlying knowledge flows are rather fuzzy and unstable in the early convergence stage. Nevertheless, novel scientific publications emerging at the intersection of different knowledge fields may reflect convergence processes. Thus, in this article, we exploit the growing number of research and digital libraries providing bibliographic metadata to propose an automated analysis of science dynamics. We utilize and adapt machine-learning methods (DeepWalk) to automatically learn a similarity measure between scientific fields from graphs constructed on bibliographic metadata. With a time-based perspective, we apply our approach to analyze the trajectories of evolving similarities between scientific fields. We validate the learned similarity measure by evaluating it within the well-explored case of cholesterol-lowering ingredients in which scientific convergence between the distinct scientific fields of nutrition and pharmaceuticals has partially taken place. Our results confirm that the similarity trajectories learned by our approach resemble the expected behavior, indicating that our approach may allow researchers and practitioners to detect and predict scientific convergence early.

Abstract

While it is well established that grammar learning success varies with age, the cause of this developmental change is largely unknown. This study examined functional MRI activation across a broad developmental sample of 165 Dutch-speaking individuals (8-25 years) as they were implicitly learning a new grammatical system. This approach allowed us to assess the direct effects of age on grammar learning ability while exploring its neural correlates. In contrast to the alleged advantage of children language learners over adults, we found that adults outperformed children. Moreover, our behavioral data showed a sharp discontinuity in the relationship between age and grammar learning performance: there was a strong positive linear correlation between 8 and 15.4 years of age, after which age had no further effect. Neurally, our data indicate two important findings: (i) during grammar learning, adults and children activate similar brain regions, suggesting continuity in the neural networks that support initial grammar learning; and (ii) activation level is age-dependent, with children showing less activation than older participants. We suggest that these age-dependent processes may constrain developmental effects in grammar learning. The present study provides new insights into the neural basis of age-related differences in grammar learning in second language acquisition.

Abstract

Anecdotal evidence suggests that learning a new foreign language (FL) makes you forget previously learned FLs. To seek empirical evidence for this claim, we tested whether learning words in a previously unknown L3 hampers subsequent retrieval of their L2 translation equivalents. In two experiments, Dutch native speakers with knowledge of English (L2), but not Spanish (L3), first completed an English vocabulary test, based on which 46 participant-specific, known English words were chosen. Half of those were then learned in Spanish. Finally, participants’ memory for all 46 English words was probed again in a picture naming task. In Experiment 1, all tests took place within one session. In Experiment 2, we separated the English pre-test from Spanish learning by a day and manipulated the timing of the English post-test (immediately after learning vs. 1 day later). By separating the post-test from Spanish learning, we asked whether consolidation of the new Spanish words would increase their interference strength. We found significant main effects of interference in naming latencies and accuracy: Participants speeded up less and were less accurate to recall words in English for which they had learned Spanish translations, compared with words for which they had not. Consolidation time did not significantly affect these interference effects. Thus, learning a new language indeed comes at the cost of subsequent retrieval ability in other FLs. Such interference effects set in immediately after learning and do not need time to emerge, even when the other FL has been known for a long time.

Abstract

Skeletal muscle remodelling and contractile dysfunction occur through both acute and chronic disease processes. These include the accumulation of insoluble aggregates of mis- folded amyloid proteins that is a pathological feature of Huntington ’ s disease (HD). While HD has been described primarily as a neurological disease, HD patients ’ exhibit pro- nounced skeletal muscle atrophy. Given that huntingtin is a ubiquitously expressed protein, skeletal muscle fibres may be at risk of a cell autonomous HD-related dysfunction. However the mechanism leading to skeletal muscle abnormalities in the clinical and pre-clinical HD settings remains unknown. To unravel this mechanism, we employed the R6/2 transgenic and Hdh Q150 knock-in mouse models of HD. We found that symptomatic animals devel- oped a progressive impairment of the contractile characteristics of the hind limb muscles tibialis anterior (TA) and extensor digitorum longus (EDL), accompanied by a significant loss of motor units in the EDL. In symptomatic animals, these pronounced functional changes were accompanied by an aberrant deregulation of contractile protein transcripts and their up-stream transcriptional regulators. In addition, HD mouse models develop a sig- nificant reduction in muscle force, possibly as a result of a deterioration in energy metabo- lism and decreased oxidation that is accompanied by the re-expression of the HDAC4- DACH2-myogenin axis. These results show that muscle dysfunction is a key pathological feature of HD.

Abstract

With the recent advancements in the field of robotics and the increased focus on having general-purpose robots widely available to the general public, it has become increasingly necessary to pursue research into Human-robot interaction (HRI). While there have been a lot of works discussing frameworks for teaching HRI in educational institutions with a few institutions already offering courses to students, a consensus on the course content still eludes the field. In this work, we highlight a few challenges and opportunities while designing an HRI course from an Indian perspective. These topics warrant further deliberations as they have a direct impact on the design of HRI courses and wider implications for the entire field.

Abstract

Frequent and predictable words are generally pronounced with less effort and are therefore acoustically more reduced than less frequent or unpredictable words. Local predictability can be operationalised by Transitional Probability (TP), which indicates how likely a word is to occur given its immediate context. We investigated whether and how probabilistic reduction effects on word durations change with adult age when reading aloud content words embedded in sentences. The results showed equally large frequency effects on verb and noun durations for both younger (Mage = 20 years) and older (Mage = 68 years) adults. Backward TP also affected word duration for younger and older adults alike. ForwardTP, however, had no significant effect on word duration in either age group. Our results resemble earlier findings of more robust BackwardTP effects compared to ForwardTP effects. Furthermore, unlike often reported decline in predictive processing with aging, probabilistic reduction effects remain stable across adulthood.

Abstract

It has been observed by several researchers that the Khoisan palate tends to lack a prominent alveolar ridge. A preliminary biomechanical model of click production was created to examine if these sounds might be subject to an anatomical bias associated with alveolar ridge size. Results suggest the bias is plausible, taking the form of decreased articulatory effort and improved volume change characteristics, however, further modelling and experimental research is required to solidify the claim.

Abstract

Learning to map words onto their referents is difficult, because there are multiple possibilities for forming these mappings. Cross-situational learning studies have shown that word-object mappings can be learned across multiple situations, as can verbs when presented in a syntactic context. However, these previous studies have presented either nouns or verbs in ambiguous contexts and thus bypass much of the complexity of multiple grammatical categories in speech. We show that noun word-learning in adults is robust when objects are moving, and that verbs can also be learned from similar scenes without additional syntactic information. Furthermore, we show that both nouns and verbs can be acquired simultaneously, thus resolving category-level as well as individual word level ambiguity. However, nouns were learned more accurately than verbs, and we discuss this in light of previous studies investigating the noun advantage in word learning.

Abstract

This paper investigated the learnability and generalizability of French schwa alternation by Dutch low-proficiency second language learners. We trained 40 participants on 24 new schwa words by exposing them equally often to the reduced and full forms of these words. We then assessed participants' accuracy and reaction times to these newly learnt words as well as 24 previously encountered schwa words with an auditory lexical decision task. Our results show learning of the new words in both forms. This suggests that lack of exposure is probably the main cause of learners' difficulties with reduced forms. Nevertheless, the full forms were slightly better recognized than the reduced ones, possibly due to phonetic and phonological properties of the reduced forms. We also observed no generalization to previously encountered words, suggesting that our participants stored both of the learnt word forms and did not create a rule that applies to all schwa words.

Abstract

EEG mu rhythms (8-13Hz) recorded at fronto-central electrodes are generally considered as markers of motor cortical activity in humans, because they are modulated when participants perform an action, when they observe another’s action or even when they imagine performing an action. In this study, we analyzed the time-frequency (TF) modulation of mu rhythms while participants read action language (“You will cut the strawberry cake”), abstract language (“You will doubt the patient´s argument”), and perceptive language (“You will notice the bright day”). The results indicated that mu suppression at fronto-central sites is associated with action language rather than with abstract or perceptive language. Also, the largest difference between conditions occurred quite late in the sentence, while reading the first noun, (contrast Action vs. Abstract), or the second noun following the action verb (contrast Action vs. Perceptive). This suggests that motor activation is associated with the integration of words across the sentence beyond the lexical processing of the action verb. Source reconstruction localized mu suppression associated with action sentences in premotor cortex (BA 6). The present study suggests (1) that the understanding of action language activates motor networks in the human brain, and (2) that this activation occurs online based on semantic integration across multiple words in the sentence.

Abstract

We considered the role of orthography and task-related processing mechanisms in the activation of morphologically related complex words during bilingual word processing. So far, it has only been shown that such morphologically related words (i.e., morphological family members) are activated through the semantic and morphological overlap they share with the target word. In this study, we investigated family size effects in Dutch-English identical cognates (e.g., tent in both languages), non-identical cognates (e.g., pil and pill, in English and Dutch, respectively), and non-cognates (e.g., chicken in English). Because of their cross-linguistic overlap in orthography, reading a cognate can result in activation of family members both languages. Cognates are therefore well-suited for studying mechanisms underlying bilingual activation of morphologically complex words. We investigated family size effects in an English lexical decision task and a Dutch-English language decision task, both performed by Dutch-English bilinguals. English lexical decision showed a facilitatory effect of English and Dutch family size on the processing of English-Dutch cognates relative to English non-cognates. These family size effects were not dependent on cognate type. In contrast, for language decision, in which a bilingual context is created, Dutch and English family size effects were inhibitory. Here, the combined family size of both languages turned out to better predict reaction time than the separate family size in Dutch or English. Moreover, the combined family size interacted with cognate type: the response to identical cognates was slowed by morphological family members in both languages. We conclude that (1) family size effects are sensitive to the task performed on the lexical items, and (2) depend on both semantic and formal aspects of bilingual word processing. We discuss various mechanisms that can explain the observed family size effects in a spreading activation framework.

Abstract

In speech, words are often reduced rather than fully pronounced (e.g., (/ˈsʌmri/ for /ˈsʌməri/, summary). Non-native listeners may have problems in processing these reduced forms, because they have encountered them less often. This paper addresses the question whether this also holds for highly proficient non-natives and for words with similar forms and meanings in the non-natives' mother tongue (i.e., cognates). In an English auditory lexical decision task, natives and highly proficient Dutch non-natives of English listened to cognates and non-cognates that were presented in full or without their post-stress schwa. The data show that highly proficient learners are affected by reduction as much as native speakers. Nevertheless, the two listener groups appear to process reduced forms differently, because non-natives produce more errors on reduced cognates than on non-cognates. While listening to reduced forms, non-natives appear to be hindered by the co-activated lexical representations of cognate forms in their native language.

Abstract

Statistical learning plays a key role in language processing, e.g., for speech segmentation. Older adults have been reported to show less statistical learning on the basis of visual input than younger adults. Given age-related changes in perception and cognition, we investigated whether statistical learning is also impaired in the auditory modality in older compared to younger adults and whether individual learning ability is associated with measures of perceptual (i.e., hearing sensitivity) and cognitive functioning in both age groups. Thirty younger and thirty older adults performed an auditory artificial-grammar-learning task to assess their statistical learning ability. In younger adults, perceptual effort came at the cost of processing resources required for learning. Inhibitory control (as indexed by Stroop colornaming performance) did not predict auditory learning. Overall, younger and older adults showed the same amount of auditory learning, indicating that statistical learning ability is preserved over the adult life span.

Abstract

Auditory discrimination of speech stimuli is an essential tool in speech and language therapy, e.g., in dysarthria rehabilitation. It is unclear, however, which listener characteristics are associated with the ability to perceive differences between one's own utterance and target speech. Knowledge about such associations may help to support patients participating in speech and language therapy programs that involve auditory discrimination tasks.
Discrimination performance was evaluated in 96 healthy participants over 60 years of age as individuals with dysarthria are typically in this age group. Participants compared meaningful words and sentences on the dimensions of loudness, pitch and speech rate. Auditory abilities were assessed using pure-tone audiometry, speech audiometry and speech understanding in noise. Cognitive measures included auditory short-term memory, working memory and processing speed. Linguistic functioning was assessed by means of vocabulary knowledge and language proficiency.
Exploratory factor analyses showed that discrimination performance was primarily associated with cognitive and linguistic skills, rather than auditory abilities. Accordingly, older adults’ discrimination performance was mainly predicted by cognitive and linguistic skills. Discrimination accuracy was higher in older adults with better speech understanding in noise, faster processing speed, and better language proficiency, but accuracy decreased with age. This raises the question whether these associations generalize to clinical populations and, if so, whether patients with better cognitive or linguistic skills may benefit more from discrimination-based therapeutic approaches than patients with poorer cognitive or linguistic abilities.

Abstract

The study of adaptive individual behavior (“animal personality”) focuses on whether individuals differ consistently in (suites of correlated) behavior(s) and whether individual-level behavior is under selection. Evidence for selection acting on personality is biased toward species where behavioral and life-history information can readily be collected in the wild, such as ungulates and passerine birds. Here, we report estimates of repeatability and syndrome structure for behaviors that an insect (field cricket; Gryllus campestris ) expresses in the wild. We used mark-recapture models to estimate personality-related survival and encounter probability and focused on a life-history phase where all individuals could readily be sampled (the nymphal stage). As proxies for risky behaviors, we assayed maximum distance from burrow, flight initiation distance, and emergence time after disturbance; all behaviors were repeatable, but there was no evidence for strong syndrome structure. Flight initiation distance alone predicted both daily survival and encounter probability: bolder individuals were more easily observed but had a shorter life span. Individuals were also somewhat repeatable in the habitat temperature under which they were assayed. Such environment repeatability can lead to upward biases in estimates of repeatability in behavior; this was not the case. Behavioral assays were, however, conducted around the subject’s personal burrow, which could induce pseudorepeatability if burrow characteristics affected behavior. Follow-up translocation experiments allowed us to distinguish individual and burrow identity effects and provided conclusive evidence for individual repeatability of flight initiation distance. Our findings, therefore, forcefully demonstrate that personality variation exists in wild insects and that it is associated with components of fitness.

Abstract

How does knowledge of real-world events shape our understanding of incoming language? Do temporal terms like “before” and “after” impact the online recruitment of real-world event knowledge? These questions were addressed in two ERP experiments, wherein participants read sentences that started with “before” or “after” and contained a critical word that rendered each sentence true or false (e.g., “Before/After the global economic crisis, securing a mortgage was easy/harder”). The critical words were matched on predictability, rated truth value, and semantic relatedness to the words in the sentence. Regardless of whether participants explicitly verified the sentences or not, false-after-sentences elicited larger N400s than true-after-sentences, consistent with the well-established finding that semantic retrieval of concepts is facilitated when they are consistent with real-world knowledge. However, although the truth judgments did not differ between before- and after-sentences, no such sentence N400 truth value effect occurred in before-sentences, whereas false-before-sentences elicited an enhanced subsequent positive ERPs. The temporal term “before” itself elicited more negative ERPs at central electrode channels than “after.” These patterns of results show that, irrespective of ultimate sentence truth value judgments, semantic retrieval of concepts is momentarily facilitated when they are consistent with the known event outcome compared to when they are not. However, this inappropriate facilitation incurs later processing costs as reflected in the subsequent positive ERP deflections. The results suggest that automatic activation of event knowledge can impede the incremental semantic processes required to establish sentence truth value.

Abstract

When we read literary fiction, we are transported to fictional places, and we feel and think along with the characters. Despite the importance of narrative in adult life and during development, the neurocognitive mechanisms underlying fiction comprehension are unclear. We used functional magnetic resonance imaging (fMRI) to investigate how individuals differently employ neural networks important for understanding others’ beliefs and intentions (mentalizing), and for sensori-motor simulation while listening to excerpts from literary novels. Localizer tasks were used to localize both the cortical motor network and the mentalizing network in participants after they listened to excerpts from literary novels. Results show that participants who had high activation in anterior medial prefrontal cortex (aMPFC; part of the mentalizing network) when listening to mentalizing content of literary fiction, had lower motor cortex activity when they listened to action-related content of the story, and vice versa. This qualifies how people differ in their engagement with fiction: some people are mostly drawn into a story by mentalizing about the thoughts and beliefs of others, whereas others engage in literature by simulating more concrete events such as actions. This study provides on-line neural evidence for the existence of qualitatively different styles of moving into literary worlds, and adds to a growing body of literature showing the potential to study narrative comprehension with neuroimaging methods.

Abstract

This paper studies the influence of adverse listening conditions on exemplar effects in priming experiments that do not instruct participants to use their episodic memories. We conducted two lexical decision experiments, in which a prime and a target represented the same word type and could be spoken by the same or a different speaker. In Experiment 1, participants listened to clear speech, and showed no exemplar effects: they recognised repetitions by the same speaker as quickly as different speaker repetitions. In Experiment 2, the stimuli contained noise, and exemplar effects did arise. Importantly, Experiment 1 elicited longer average RTs than Experiment 2, a result that contradicts the time-course hypothesis, according to which exemplars only play a role when processing is slow. Instead, our findings support the hypothesis that exemplar effects arise under adverse listening conditions, when participants are stimulated to use their episodic memories in addition to their mental lexicons.

Abstract

An inference is defined as the information that is not expressed explicitly by the text but is derived on the basis of the understander's knowledge and is encoded in the mental representation of the text. Inferencing is considered as a central component in discourse understanding. Experimental methods to detect inferences, established findings, and some developments are reviewed. Attention is paid to the relation between inference processes and the brain.

Abstract

Recent years have seen a small but growing body of psycholinguistic research focused on typologically diverse languages. This represents an important development for the field, where theorising is still largely guided by the often implicit assumption of universality. This paper introduces a special issue of Language, Cognition and Neuroscience devoted to the topic of cross-linguistic and field-based approaches to the study of psycholinguistics. The papers in this issue draw on data from a variety of genetically and areally divergent languages, to address questions in the production and comprehension of phonology, morphology, words, and sentences. To contextualise these studies, we provide an overview of the field of cross-linguistic psycholinguistics, from its early beginnings to the present day, highlighting instances where cross-linguistic data have significantly contributed to psycholinguistic theorising.

Abstract

The scope of planning during sentence formulation is known to be flexible, as it can be influenced by speakers' communicative goals and language production pressures (among other factors). Two eye-tracked picture description experiments tested whether the time course of formulation is also modulated by grammatical structure and thus whether differences in linear word order across languages affect the breadth and order of conceptual and linguistic encoding operations. Native speakers of Tzeltal [a primarily verb–object–subject (VOS) language] and Dutch [a subject–verb–object (SVO) language] described pictures of transitive events. Analyses compared speakers' choice of sentence structure across events with more accessible and less accessible characters as well as the time course of formulation for sentences with different word orders. Character accessibility influenced subject selection in both languages in subject-initial and subject-final sentences, ruling against a radically incremental formulation process. In Tzeltal, subject-initial word orders were preferred over verb-initial orders when event characters had matching animacy features, suggesting a possible role for similarity-based interference in influencing word order choice. Time course analyses revealed a strong effect of sentence structure on formulation: In subject-initial sentences, in both Tzeltal and Dutch, event characters were largely fixated sequentially, while in verb-initial sentences in Tzeltal, relational information received priority over encoding of either character during the earliest stages of formulation. The results show a tight parallelism between grammatical structure and the order of encoding operations carried out during sentence formulation.

Abstract

To what extent are the planning processes involved in producing sentences fine-tuned to grammatical properties of specific languages? In this chapter we survey the small body of cross-linguistic research that bears on this question, focusing in particular on recent evidence from eye-tracking studies. Because eye-tracking methods provide a very fine-grained temporal measure of how conceptual and linguistic planning unfold in real time, they serve as an important complement to standard psycholinguistic methods. Moreover, the advent of portable eye-trackers in recent years has, for the first time, allowed eye-tracking techniques to be used with language populations that are located far away from university laboratories. This has created the exciting opportunity to extend the typological base of vision-based psycholinguistic research and address key questions in language production with new language comparisons.

Abstract

The highly polygenic and pleiotropic nature of behavioural traits, psychiatric disorders and structural and functional brain phenotypes complicate mechanistic interpretation of related genome-wide association study (GWAS) signals, thereby obscuring underlying causal biological processes. We propose genomic principal and independent component analysis (PCA, ICA) to decompose a large set of univariate GWAS statistics of multimodal brain traits into more interpretable latent genomic components. Here we introduce and evaluate this novel methods various analytic parameters and reproducibility across independent samples. Two UK Biobank GWAS summary statistic releases of 2240 imaging-derived phenotypes (IDPs) were retrieved. Genome-wide beta-values and their corresponding standard-error scaled z-values were decomposed using genomic PCA/ICA. We evaluated variance explained at multiple dimensions up to 200. We tested the inter-sample reproducibility of output of dimensions 5, 10, 25 and 50. Reproducibility statistics of the respective univariate GWAS served as benchmarks. Reproducibility of 10-dimensional PCs and ICs showed the best trade-off between model complexity and robustness and variance explained (PCs: |rz − max| = 0.33, |rraw − max| = 0.30; ICs: |rz − max| = 0.23, |rraw − max| = 0.19). Genomic PC and IC reproducibility improved substantially relative to mean univariate GWAS reproducibility up to dimension 10. Genomic components clustered along neuroimaging modalities. Our results indicate that genomic PCA and ICA decompose genetic effects on IDPs from GWAS statistics with high reproducibility by taking advantage of the inherent pleiotropic patterns. These findings encourage further applications of genomic PCA and ICA as fully data-driven methods to effectively reduce the dimensionality, enhance the signal to noise ratio and improve interpretability of high-dimensional multitrait genome-wide analyses.

Abstract

This study asks how users of British Sign Language (BSL) recognize individual signs in connected sign sequences. We examined whether this is achieved through modality-specific or modality-general segmentation procedures. A modality-specific feature of signed languages is that, during continuous signing, there are salient transitions between sign locations. We used the sign-spotting task to ask if and how BSL signers use these transitions in segmentation. A total of 96 real BSL signs were preceded by nonsense signs which were produced in either the target location or another location (with a small or large transition). Half of the transitions were within the same major body area (e.g., head) and half were across body areas (e.g., chest to hand). Deaf adult BSL users (a group of natives and early learners, and a group of late learners) spotted target signs best when there was a minimal transition and worst when there was a large transition. When location changes were present, both groups performed better when transitions were to a different body area than when they were within the same area. These findings suggest that transitions do not provide explicit sign-boundary cues in a modality-specific fashion. Instead, we argue that smaller transitions help recognition in a modality-general way by limiting lexical search to signs within location neighbourhoods, and that transitions across body areas also aid segmentation in a modality-general way, by providing a phonotactic cue to a sign boundary. We propose that sign segmentation is based on modality-general procedures which are core language-processing mechanisms

Abstract

There is growing interest in learners’ cognitive capacities to process a second language (L2) at first exposure to the target language. Evidence suggests that L2 learners are capable of processing novel words by exploiting phonological information from their first language (L1). Hearing adult learners of a sign language, however, cannot fall back on their L1 to process novel signs because the modality differences between speech (aural–oral) and sign (visual-manual) do not allow for direct cross-linguistic influence. Sign language learners might use alternative strategies to process input expressed in the manual channel. Learners may rely on iconicity, the direct relationship between a sign and its referent. Evidence up to now has shown that iconicity facilitates learning in non-signers, but it is unclear whether it also facilitates sign production. In order to fill this gap, the present study investigated how iconicity influenced articulation of the phonological components of signs. In Study 1, hearing non-signers viewed a set of iconic and arbitrary signs along with their English translations and repeated the signs as accurately as possible immediately after. The results show that participants imitated iconic signs significantly less accurately than arbitrary signs. In Study 2, a second group of hearing non-signers imitated the same set of signs but without the accompanying English translations. The same lower accuracy for iconic signs was observed. We argue that learners rely on iconicity to process manual input because it brings familiarity to the target (sign) language. However, this reliance comes at a cost as it leads to a more superficial processing of the signs’ full phonetic form. The present findings add to our understanding of learners’ cognitive capacities at first exposure to a signed L2, and raises new theoretical questions in the field of second language acquisition

Abstract

The present study implemented a sign-repetition task at two points in time to hearing adult learners of British Sign Language and explored how each phonological parameter, sign complexity, and iconicity affected sign production over an 11-week (22-hour) instructional period. The results show that training improves articulation accuracy and that some sign components are produced more accurately than others: Handshape was the most difficult, followed by movement, then orientation, and finally location. Iconic signs were articulated less accurately than arbitrary signs because the direct sign-referent mappings and perhaps their similarity with iconic co-speech gestures prevented learners from focusing on the exact phonological structure of the sign. This study shows that multiple phonological features pose greater demand on the production of the parameters of signs and that iconicity interferes in the exact articulation of their constituents

Abstract

The present study investigated the priming effect of iconic signs in the mental lexicon of hearing adults. Non-signers and proficient British Sign Language (BSL) users took part in a cross-modal lexical decision task. The results indicate that iconic signs activated semantically related words in non-signers' lexicon. Activation occurred regardless of the type of referent because signs depicting actions and perceptual features of an object yielded the same response times. The pattern of activation was different in proficient signers because only action signs led to cross-modal activation. We suggest that non-signers process iconicity in signs in the same way as they do gestures, but after acquiring a sign language, there is a shift in the mechanisms used to process iconic manual structures

Abstract

Animal vocal communication often relies on call sequences. The temporal patterns of such sequences can be adjusted to other callers, follow complex rhythmic structures or exhibit a metronome-like pattern (i.e., isochronous). How regular are the temporal patterns in animal signals, and what influences their precision? If present, are rhythms already there early in ontogeny? Here, we describe an exploratory study of Cape fur seal (Arctocephalus pusillus pusillus) barks—a vocalisation type produced across many pinniped species in rhythmic, percussive bouts. This study is the first quantitative description of barking in Cape fur seal pups. We analysed the rhythmic structures of spontaneous barking bouts of pups and adult females from the breeding colony in Cape Cross, Namibia. Barks of adult females exhibited isochrony, that is they were produced at fairly regular points in time. Instead, intervals between pup barks were more variable, that is skipping a bark in the isochronous series occasionally. In both age classes, beat precision, that is how well the barks followed a perfect template, was worse when barking at higher rates. Differences could be explained by physiological factors, such as respiration or arousal. Whether, and how, isochrony develops in this species remains an open question. This study provides evidence towards a rhythmic production of barks in Cape fur seal pups and lays the groundwork for future studies to investigate the development of rhythm using multidimensional metrics.

Abstract

Both music and language are found in all known human societies, yet no studies have compared similarities and differences between song, speech, and instrumental music on a global scale. In this Registered Report, we analyzed two global datasets: (i) 300 annotated audio recordings representing matched sets of traditional songs, recited lyrics, conversational speech, and instrumental melodies from our 75 coauthors speaking 55 languages; and (ii) 418 previously published adult-directed song and speech recordings from 209 individuals speaking 16 languages. Of our six preregistered predictions, five were strongly supported: Relative to speech, songs use (i) higher pitch, (ii) slower temporal rate, and (iii) more stable pitches, while both songs and speech used similar (iv) pitch interval size and (v) timbral brightness. Exploratory analyses suggest that features vary along a “musi-linguistic” continuum when including instrumental melodies and recited lyrics. Our study provides strong empirical evidence of cross-cultural regularities in music and speech.

Abstract

Across the animal kingdom, neural responses in the auditory cortex are suppressed during vocalization, and humans are no exception. A common hypothesis is that suppression increases sensitivity to auditory feedback, enabling the detection of vocalization errors. This hypothesis has been previously confirmed in non-human primates, however a direct link between auditory suppression and sensitivity in human speech monitoring remains elusive. To address this issue, we obtained intracranial electroencephalography (iEEG) recordings from 35 neurosurgical participants during speech production. We first characterized the detailed topography of auditory suppression, which varied across superior temporal gyrus (STG). Next, we performed a delayed auditory feedback (DAF) task to determine whether the suppressed sites were also sensitive to auditory feedback alterations. Indeed, overlapping sites showed enhanced responses to feedback, indicating sensitivity. Importantly, there was a strong correlation between the degree of auditory suppression and feedback sensitivity, suggesting suppression might be a key mechanism that underlies speech monitoring. Further, we found that when participants produced speech with simultaneous auditory feedback, posterior STG was selectively activated if participants were engaged in a DAF paradigm, suggesting that increased attentional load can modulate auditory feedback sensitivity.

Abstract

Languages typically express semantic components of motion events such as manner (roll) and path (down) in separate lexical items. We explore how these combinatorial possibilities of language arise by focusing on (i) gestures produced by deaf children who lack access to input from a conventional language (homesign); (ii) gestures produced by hearing adults and children while speaking; and (iii) gestures used by hearing adults without speech when asked to do so in elicited descriptions of motion events with simultaneous manner and path. Homesigners tended to conflate manner and path in one gesture, but also used a mixed form, adding a manner and/or path gesture to the conflated form sequentially. Hearing speakers, with or without speech, used the conflated form, gestured manner, or path, but rarely used the mixed form. Mixed form may serve as an intermediate structure on the way to the discrete and sequenced forms found in natural languages.

Abstract

* These two authors contributed equally to this study
Statistical learning – the ability to extract distributional regularities from input – is suggested to be key to language acquisition. Yet, evidence for the human capacity for statistical learning comes mainly from studies conducted in carefully controlled settings without auditory distraction. While such conditions permit careful examination of learning, they do not reflect the naturalistic language learning experience, which is replete with auditory distraction – including competing talkers. Here, we examine how statistical language learning proceeds in a virtual cocktail party environment, where the to-be-learned input is presented alongside a competing speech stream with its own distributional regularities. During exposure, participants in the Dual Talker group concurrently heard two novel languages, one produced by a female talker and one by a male talker, with each talker virtually positioned at opposite sides of the listener (left/right) using binaural acoustic manipulations. Selective attention was manipulated by instructing participants to attend to only one of the two talkers. At test, participants were asked to distinguish words from part-words for both the attended and the unattended languages. Results indicated that participants’ accuracy was significantly higher for trials from the attended vs. unattended
language. Further, the performance of this Dual Talker group was no different compared to a control group who heard only one language from a single talker (Single Talker group). We thus conclude that statistical learning is modulated by selective attention, being relatively robust against the additional cognitive load provided by competing speech, emphasizing its efficiency in naturalistic language learning situations.

Abstract

In everyday human communication, we often express our communicative intentions by manually pointing out referents in the material world around us to an addressee, often in tight synchronization with referential speech. This study investigated whether and how the kinematic form of index finger pointing gestures is shaped by the gesturer's communicative intentions and how this is modulated by the presence of concurrently produced speech. Furthermore, we explored the neural mechanisms underpinning the planning of communicative pointing gestures and speech. Two experiments were carried out in which participants pointed at referents for an addressee while the informativeness of their gestures and speech was varied. Kinematic and electrophysiological data were recorded online. It was found that participants prolonged the duration of the stroke and poststroke hold phase of their gesture to be more communicative, in particular when the gesture was carrying the main informational burden in their multimodal utterance. Frontal and P300 effects in the ERPs suggested the importance of intentional and modality-independent attentional mechanisms during the planning phase of informative pointing gestures. These findings contribute to a better understanding of the complex interplay between action, attention, intention, and language in the production of pointing gestures, a communicative act core to human interaction.

Abstract

A fundamental property of language is that it can be used to refer to entities in the extra-linguistic physical context of a conversation in order to establish a joint focus of attention on a referent. Typological and psycholinguistic work across a wide range of languages has put forward at least two different theoretical views on demonstrative reference. Here we contrasted and tested these two accounts by investigating the electrophysiological brain activity underlying the construction of indexical meaning in comprehension. In two EEG experiments, participants watched pictures of a speaker who referred to one of two objects using speech and an index-finger pointing gesture. In contrast with separately collected native speakers’ linguistic intuitions, N400 effects showed a preference for a proximal demonstrative when speaker and addressee were in a face-to-face orientation and all possible referents were located in the shared space between them, irrespective of the physical proximity of the referent to the speaker. These findings reject egocentric proximity-based accounts of demonstrative reference, support a sociocentric approach to deixis, suggest that interlocutors construe a shared space during conversation, and imply that the psychological proximity of a referent may be more important than its physical proximity.

Abstract

Comprehension of pointing gestures is fundamental to human communication. However, the neural mechanisms
that subserve the integration of pointing gestures and speech in visual contexts in comprehension
are unclear. Here we present the results of an fMRI study in which participants watched images of an
actor pointing at an object while they listened to her referential speech. The use of a mismatch paradigm
revealed that the semantic unication of pointing gesture and speech in a triadic context recruits left
inferior frontal gyrus. Complementing previous ndings, this suggests that left inferior frontal gyrus
semantically integrates information across modalities and semiotic domains.

Abstract

From an early age, people exhibit strong links between certain visual (e.g. size) and acoustic (e.g. duration) dimensions. Do people instinctively extend these crossmodal correspondences to vocalization? We examine the ability of congenitally deaf Chinese children and young adults (age M = 12.4 years, SD = 3.7 years) to generate iconic vocalizations to distinguish items with contrasting magnitude (e.g., big vs. small ball). Both deaf and hearing (M = 10.1 years, SD = 0.83 years) participants produced longer, louder vocalizations for greater magnitude items. However, only hearing participants used pitch—higher pitch for greater magnitude – which counters the hypothesized, innate size “frequency code”, but fits with Mandarin language and culture. Thus our results show that the translation of visible magnitude into the duration and intensity of vocalization transcends auditory experience, whereas the use of pitch appears more malleable to linguistic and cultural influence.

Abstract

Recent experiments have shown that people iconically modulate their prosody corresponding with the meaning of their utterance (e.g., Shintel et al., 2006). This article reports findings from a story reading task that expands the investigation of iconic prosody to abstract meanings in addition to concrete ones. Participants read stories that contrasted along concrete and abstract semantic dimensions of speed (e.g., a fast drive, slow career progress) and size (e.g., a small grasshopper, an important contract). Participants read fast stories at a faster rate than slow stories, and big stories with a lower pitch than small stories. The effect of speed was distributed across the stories, including portions that were identical across stories, whereas the size effect was localized to size-related words. Overall, these findings enrich the documentation of iconicity in spoken language and bear on our understanding of the relationship between gesture and speech.

Abstract

Studies of gestural communication systems find that they originate from spontaneously created iconic gestures. Yet, we know little about how people create vocal communication systems, and many have suggested that vocalizations do not afford iconicity beyond trivial instances of onomatopoeia. It is unknown whether people can generate vocal communication systems through a process of iconic creation similar to gestural systems. Here, we examine the creation and development of a rudimentary vocal symbol system in a laboratory setting. Pairs of participants generated novel vocalizations for 18 different meanings in an iterative ‘vocal’ charades communication game. The communicators quickly converged on stable vocalizations, and naive listeners could correctly infer their meanings in subsequent playback experiments. People's ability to guess the meanings of these novel vocalizations was predicted by how close the vocalization was to an iconic ‘meaning template’ we derived from the production data. These results strongly suggest that the meaningfulness of these vocalizations derived from iconicity. Our findings illuminate a mechanism by which iconicity can ground the creation of vocal symbols, analogous to the function of iconicity in gestural communication systems.

Abstract

We describe the repertoire of learned vocal and breathing-related behaviors (VBBs) performed by the enculturated gorilla Koko. We examined a large video corpus of Koko and observed 439 VBBs spread across 161 bouts. Our analysis shows that Koko exercises voluntary control over the performance of nine distinctive VBBs, which involve variable coordination of her breathing, larynx, and supralaryngeal articulators like the tongue and lips. Each of these behaviors is performed in the context of particular manual action routines and gestures. Based on these and other findings, we suggest that vocal learning and the ability to exercise volitional control over vocalization, particularly in a multimodal context, might have figured relatively early into the evolution of language, with some rudimentary capacity in place at the time of our last common ancestor with great apes.

Abstract

The spatial affordances of the visual modality give rise to a high degree of similarity between sign languages in the spatial domain. This stands in contrast to the vast structural and semantic diversity in linguistic encoding of space found in spoken languages. However, the possibility and nature of linguistic diversity in spatial encoding in sign languages has not been rigorously investigated by systematic crosslinguistic comparison. Here, we compare locative expression in two unrelated sign languages, Turkish Sign Language (Türk İşaret Dili, TİD) and German Sign Language (Deutsche Gebärdensprache, DGS), focusing on the expression of figure-ground (e.g. cup on table) and figure-figure (e.g. cup next to cup) relationships in a discourse context. In addition to similarities, we report qualitative and quantitative differences between the sign languages in the formal devices used (i.e. unimanual vs. bimanual; simultaneous vs. sequential) and in the degree of iconicity of the spatial devices. Our results suggest that sign languages may display more diversity in the spatial domain than has been previously assumed, and in a way more comparable with the diversity found in spoken languages. The study contributes to a more comprehensive understanding of how space gets encoded in language

Abstract

For humans, the ability to communicate and use language is instantiated not only in the vocal modality but also in the visual modality. The main examples of this are sign languages and (co-speech) gestures. Sign languages, the natural languages of Deaf communities, use systematic and conventionalized movements of the hands, face, and body for linguistic expression. Co-speech gestures, though non-linguistic, are produced in tight semantic and temporal integration with speech and constitute an integral part of language together with speech. The articles in this issue explore and document how gestures and sign languages are similar or different and how communicative expression in the visual modality can change from being gestural to grammatical in nature through processes of conventionalization. As such, this issue contributes to our understanding of how the visual modality shapes language and the emergence of linguistic structure in newly developing systems. Studying the relationship between signs and gestures provides a new window onto the human ability to recruit multiple levels of representation (e.g., categorical, gradient, iconic, abstract) in the service of using or creating conventionalized communicative systems.

Abstract

Establishing and maintaining reference is a crucial part of discourse. In spoken languages, differential linguistic devices mark referents occurring in different referential contexts, that is, introduction, maintenance, and re-introduction contexts. Speakers using gestures as well as users of sign languages have also been shown to mark referents differentially depending on the referential context. This article investigates the modality-specific contribution of the visual modality in marking referential context by providing a direct comparison between sign language (German Sign Language; DGS) and co-speech gesture with speech (German) in elicited narratives. Across all forms of expression, we find that referents in subject position are referred to with more marking material in re-introduction contexts compared to maintenance contexts. Furthermore, we find that spatial modification is used as a modality-specific strategy in both DGS and German co-speech gesture, and that the configuration of referent locations in sign space and gesture space corresponds in an iconic and consistent way to the locations of referents in the narrated event. However, we find that spatial modification is used in different ways for marking re-introduction and maintenance contexts in DGS and German co-speech gesture. The findings are discussed in relation to the unique contribution of the visual modality to reference tracking in discourse when it is used in a unimodal system with full linguistic structure (i.e., as in sign) versus in a bimodal system that is a composite of speech and gesture

Abstract

Signed languages exhibit iconicity (resemblance between form and meaning) across their vocabulary, and many non-Indo-European spoken languages feature sizable classes of iconic words known as ideophones. In comparison, Indo-European languages like English and Spanish are believed to be arbitrary outside of a small number of onomatopoeic words. In three experiments with English and two with Spanish, we asked native speakers to rate the iconicity of ~600 words from the English and Spanish MacArthur-Bates Communicative Developmental Inventories. We found that iconicity in the words of both languages varied in a theoretically meaningful way with lexical category. In both languages, adjectives were rated as more iconic than nouns and function words, and corresponding to typological differences between English and Spanish in verb semantics, English verbs were rated as relatively iconic compared to Spanish verbs. We also found that both languages exhibited a negative relationship between iconicity ratings and age of acquisition. Words learned earlier tended to be more iconic, suggesting that iconicity in early vocabulary may aid word learning. Altogether these findings show that iconicity is a graded quality that pervades vocabularies of even the most “arbitrary” spoken languages. The findings provide compelling evidence that iconicity is an important property of all languages, signed and spoken, including Indo-European languages.

Abstract

Scholars have documented substantial classes of iconic vocabulary in many non-Indo-European languages. In comparison, Indo-European languages like English are assumed to be arbitrary outside of a small number of onomatopoeic words. In three experiments, we asked English speakers to rate the iconicity of words from the MacArthur-Bates Communicative Developmental Inventory. We found English—contrary to common belief—exhibits iconicity that correlates with age of acquisition and differs across lexical classes. Words judged as most iconic are learned earlier, in accord with findings that iconic words are easier to learn. We also find that adjectives and verbs are more iconic than nouns, supporting the idea that iconicity provides an extra cue in learning more difficult abstract meanings. Our results provide new evidence for a relationship between iconicity and word learning and suggest iconicity may be a more pervasive property of spoken languages than previously thought.

Abstract

In this study, we investigated when children develop adult-like verb–structure links, and examined two mechanisms, associative and error-based learning, that might explain how these verb–structure links are learned. Using structural priming, we tested children’s and adults’ ability to use verb–structure links in production in three ways; by manipulating: (1) verb overlap between prime and target, (2) target verb bias, and (3) prime verb bias. Children (aged 3–4 and 5–6 years old) and adults heard and produced double object dative (DOD) and prepositional object dative (PD) primes with DOD- and PD-biased verbs. Although all age groups showed significant evidence of structural priming, only adults showed increased priming when there was verb overlap between prime and target sentences (the lexical boost). The effect of target verb bias also grew with development. Critically, however, the effect of prime verb bias on the size of the priming effect (prime surprisal) was larger in children than in adults, suggesting that verb–structure links are present at the earliest age tested. Taken as a whole, the results suggest that children begin to acquire knowledge about verb-argument structure preferences early in acquisition, but that the ability to use adult-like verb bias in production gradually improves over development. We also argue that this pattern of results is best explained by a learning model that uses an error-based learning mechanism.

Abstract

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance.

We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible.

We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities.

Abstract

Two major components form the basis of spoken word production: the access of conceptual and lexical/phonological information in long-term memory, and motor preparation and execution of an articulatory program. Whereas the motor aspects of word production have been well characterized as reflected in alpha-beta desynchronization, the memory aspects have remained poorly understood. Using magnetoencephalography, we investigated the neurophysiological signature of not only motor but also memory aspects of spoken-word production. Participants named or judged pictures after reading sentences. To probe the involvement of the memory component, we manipulated sentence context. Sentence contexts were either constraining or nonconstraining toward the final word, presented as a picture. In the judgment task, participants indicated with a left-hand button press whether the picture was expected given the sentence. In the naming task, they named the picture. Naming and judgment were faster with constraining than nonconstraining contexts. Alpha-beta desynchronization was found for constraining relative to nonconstraining contexts pre-picture presentation. For the judgment task, beta desynchronization was observed in left posterior brain areas associated with conceptual processing and in right motor cortex. For the naming task, in addition to the same left posterior brain areas, beta desynchronization was found in left anterior and posterior temporal cortex (associated with memory aspects), left inferior frontal cortex, and bilateral ventral premotor cortex (associated with motor aspects). These results suggest that memory and motor components of spoken word production are reflected in overlapping brain oscillations in the beta band.

Abstract

Previous dual-task studies examining the locus of semantic interference of distractor words in picture naming have obtained diverging results. In these studies, participants manually responded to tones and named pictures while ignoring distractor words (picture-word interference, PWI) with varying stimulus onset asynchrony (SOA) between tone and PWI stimulus. Whereas some studies observed no semantic interference at short SOAs, other studies observed effects of similar magnitude at short and long SOAs. The absence of semantic interference in some studies may perhaps be due to better reading skill of participants in these than in the other studies. According to such a reading-ability account, participants' reading skill should be predictive of the magnitude of their interference effect at short SOAs. To test this account, we conducted a dual-task study with tone discrimination and PWI tasks and measured participants' reading ability. The semantic interference effect was of similar magnitude at both short and long SOAs. Participants' reading ability was predictive of their naming speed but not of their semantic interference effect, contrary to the reading ability account. We conclude that the magnitude of semantic interference in picture naming during dual-task performance does not depend on reading skill.

Abstract

In animals, the rhythmical properties of calls are known to be shaped by physical constraints and the necessity of conveying information. As a consequence, investigating rhythmical properties in relation to different environmental conditions can help to shed light on the relationship between environment and species behavior from an evolutionary perspective. Sciaena umbra (fam. Sciaenidae) male fish emit reproductive calls characterized by a simple isochronous, i.e., metronome-like rhythm (the so-called R-pattern). Here, S. umbra R-pattern rhythm properties were assessed and compared between four different sites located along the Mediterranean basin (Mallorca, Venice, Trieste, Crete); furthermore, for one location, two datasets collected 10 years apart were available. Recording sites differed in habitat types, vessel density and acoustic richness; despite this, S. umbra R-calls were isochronous across all locations. A degree of variability was found only when considering the beat frequency, which was temporally stable, but spatially variable, with the beat frequency being faster in one of the sites (Venice). Statistically, the beat frequency was found to be dependent on the season (i.e. month of recording) and potentially influenced by the presence of soniferous competitors and human-generated underwater noise. Overall, the general consistency in the measured rhythmical properties (isochrony and beat frequency) suggests their nature as a fitness-related trait in the context of the S. umbra reproductive behavior and calls for further evaluation as a communicative cue.

Abstract

This study examines online processing and offline judgments of subject-verb person agreement with a focus on how this is impacted by markedness in heritage speakers (HSs) of Italian. To this end, 54 adult HSs living in Germany and 40 homeland Italian speakers completed a self-paced reading task (SPRT) and a grammaticality judgment task (GJT). Markedness was manipulated by probing agreement with both first-person (marked) and third-person (unmarked) subjects. Agreement was manipulated by crossing first-person marked subjects with third-person unmarked verbs and vice versa. Crucially, person violations with 1st person subjects (e.g., io *suona la chitarra “I plays-3rd-person the guitar”) yielded significantly shorter RTs in the SPRT and higher accuracy in the GJT than the opposite error type (e.g., il giornalista *esco spesso “the journalist go-1st-person out often”). This effect is consistent with the claim that when the first element in the dependency is marked (first person), the parser generates stronger predictions regarding upcoming agreeing elements. These results nicely align with work from the same populations investigating the impact of morphological markedness on grammatical gender agreement, suggesting that markedness impacts agreement similarly in two distinct grammatical domains and that sensitivity to markedness is more prevalent for HSs.

Abstract

Over the last decade, there has been a slow but steady accumulation of psycholinguistic research focusing on typologically diverse languages. In this review, we provide an overview of the psycholinguistic research on Philippine languages at the sentence level. We first discuss the grammatical features of these languages that figure prominently in existing research. We identify four linguistic domains that have received attention from language researchers and summarize the empirical terrain. We advance two claims that emerge across these different domains: (a) The agent-first pressure plays a central role in many of the findings, and (b) the generalization that the patient argument is the syntactically privileged argument cannot be reduced to frequency, but instead is an emergent phenomenon caused by the alignment of competing pressures toward an optimal candidate. We connect these language-specific claims to language-general theories of sentence processing.

Abstract

Visual stimuli quickly activate a broad network of brain areas that often show reciprocal structural connections between them. Activity at short latencies (<100 ms) is thought to represent a feed-forward activation of widespread cortical areas, but fast activation combined with reciprocal connectivity between areas in principle allows for two-way, recurrent interactions to occur at short latencies after stimulus onset. Here we combined EEG source-imaging and Granger-causal modeling with high temporal resolution to investigate whether recurrent and top-down interactions between visual and attentional brain areas can be identified and distinguished at short latencies in humans. We investigated the directed interactions between widespread occipital, parietal and frontal areas that we localized within participants using fMRI. The connectivity results showed two-way interactions between area MT and V1 already at short latencies. In addition, the results suggested a large role for lateral parietal cortex in coordinating visual activity that may be understood as an ongoing top-down allocation of attentional resources. Our results support the notion that indirect pathways allow early, evoked driving from MT to V1 to highlight spatial locations of motion transients, while influence from parietal areas is continuously exerted around stimulus onset, presumably reflecting task-related attentional processes.

Abstract

Peer behaviour plays an important role in the development of social adjustment, though little is known about its genetic architecture. We conducted a twin study combined with a genome-wide complex trait analysis (GCTA) and a genome-wide screen to characterise genetic influences on problematic peer behaviour during childhood and adolescence. This included a series of longitudinal measures (parent-reported Strengths-and-Difficulties Questionnaire) from a UK population-based birth-cohort (ALSPAC, 4–17 years), and a UK twin sample (TEDS, 4–11 years). Longitudinal twin analysis (TEDS; N ≤ 7,366 twin pairs) showed that peer problems in childhood are heritable (4–11 years, 0.60 < twin-h 2 ≤ 0.71) but genetically heterogeneous from age to age (4–11 years, twin-r g = 0.30). GCTA (ALSPAC: N ≤ 5,608, TEDS: N ≤ 2,691) provided furthermore little support for the contribution of measured common genetic variants during childhood (4–12 years, 0.02 < GCTA-h 2(Meta) ≤ 0.11) though these influences become stronger in adolescence (13–17 years, 0.14 < GCTA-h 2(ALSPAC) ≤ 0.27). A subsequent cross-sectional genome-wide screen in ALSPAC (N ≤ 6,000) focussed on peer problems with the highest GCTA-heritability (10, 13 and 17 years, 0.0002 < GCTA-P ≤ 0.03). Single variant signals (P ≤ 10−5) were followed up in TEDS (N ≤ 2835, 9 and 11 years) and, in search for autism quantitative trait loci, explored within two autism samples (AGRE: N Pedigrees = 793; ACC: N Cases = 1,453/N Controls = 7,070). There was, however, no evidence for association in TEDS and little evidence for an overlap with the autistic continuum. In summary, our findings suggest that problematic peer relationships are heritable but genetically complex and heterogeneous from age to age, with an increase in common measurable genetic variation during adolescence.

Abstract

This article aims to explore the scope of a Situated and Embodied Social Psychology (ESP). At first sight, social cognition seems embodied cognition par excellence. Social cognition is first and foremost a supra-individual, interactive, and dynamic process (Semin & Smith, 2013). Radical approaches in Situated/Embodied Cognitive Science (Enactivism) claim that social cognition consists in an emergent pattern of interaction between a continuously coupled organism and the (social) environment; it rejects representationalist accounts of cognition (Hutto & Myin, 2013). However, mainstream ESP (Barsalou, 1999, 2008) still takes a rather representation-friendly approach that construes embodiment in terms of specific bodily formatted representations used (activated) in social cognition. We argue that mainstream ESP suffers from vestiges of theoretical solipsism, which may be resolved by going beyond internalistic spirit that haunts mainstream ESP today.

Abstract

In response to: How to learn about teaching: An evolutionary framework for the study of teaching behavior in humans and other animals

Arguments about the nature of teaching have depended principally on naturalistic observation and some experimental work. Additional measurement tools, and physiological variations and manipulations can provide insights on the intrinsic structure and state of the participants better than verbal descriptions alone: namely, time-series analysis, and examination of the role of hormones and neuromodulators on the behaviors of teacher and pupil.

Abstract

Comparative pattern learning experiments investigate how different species find regularities in sensory input, providing insights into cognitive processing in humans and other animals. Past research has focused either on one species’ ability to process pattern classes or different species’ performance in recognizing the same pattern, with little attention to individual and species-specific heuristics and decision strategies. We trained and tested two bird species, pigeons (Columba livia) and kea (Nestor notabilis, a parrot species), on visual patterns using touch-screen technology. Patterns were composed of several abstract elements and had varying degrees of structural complexity. We developed a model selection paradigm, based on regular expressions, that allowed us to reconstruct the specific decision strategies and cognitive heuristics adopted by a given individual in our task. Individual birds showed considerable differences in the number, type and heterogeneity of heuristic strategies adopted. Birds’ choices also exhibited consistent species-level differences. Kea adopted effective heuristic strategies, based on matching learned bigrams to stimulus edges. Individual pigeons, in contrast, adopted an idiosyncratic mix of strategies that included local transition probabilities and global string similarity. Although performance was above chance and quite high for kea, no individual of either species provided clear evidence of learning exactly the rule used to generate the training stimuli. Our results show that similar behavioral outcomes can be achieved using dramatically different strategies and highlight the dangers of combining multiple individuals in a group analysis. These findings, and our general approach, have implications for the design of future pattern learning experiments, and the interpretation of comparative cognition research more generally.

Abstract

Cadherin-13 (CDH13), a unique glycosylphosphatidylinositol-anchored member of the cadherin family of cell adhesion molecules, has been identified as a risk gene for attention-deficit/hyperactivity disorder (ADHD) and various comorbid neurodevelopmental and psychiatric conditions, including depression, substance abuse, autism spectrum disorder and violent behavior, while the mechanism whereby CDH13 dysfunction influences pathogenesis of neuropsychiatric disorders remains elusive. Here we explored the potential role of CDH13 in the inhibitory modulation of brain activity by investigating synaptic function of GABAergic interneurons. Cellular and subcellular distribution of CDH13 was analyzed in the murine hippocampus and a mouse model with a targeted inactivation of Cdh13 was generated to evaluate how CDH13 modulates synaptic activity of hippocampal interneurons and behavioral domains related to psychopathologic (endo)phenotypes. We show that CDH13 expression in the cornu ammonis (CA) region of the hippocampus is confined to distinct classes of interneurons. Specifically, CDH13 is expressed by numerous parvalbumin and somatostatin-expressing interneurons located in the stratum oriens, where it localizes to both the soma and the presynaptic compartment. Cdh13−/− mice show an increase in basal inhibitory, but not excitatory, synaptic transmission in CA1 pyramidal neurons. Associated with these alterations in hippocampal function, Cdh13−/− mice display deficits in learning and memory. Taken together, our results indicate that CDH13 is a negative regulator of inhibitory synapses in the hippocampus, and provide insights into how CDH13 dysfunction may contribute to the excitatory/inhibitory imbalance observed in neurodevelopmental disorders, such as ADHD and autism.

Abstract

Talhelm et al. (2014) test the hypothesis that activities which require more intensive collaboration foster more collectivist cultures. They demonstrate that a measure of collectivism correlates with the proportion of cultivated land devoted to rice paddies, which require more work to grow and maintain than other grains. The data come from individual measures of provinces in China. While the data is analyzed carefully, one aspect that is not directly controlled for is the historical relations between these provinces. Spurious correlations can occur between cultural traits that are inherited from ancestor cultures or borrowed through contact, what is commonly known as Galton's problem (Roberts and Winters, 2013). Effectively, Talhelm et al. treat the measures of each province as independent samples, while in reality both farming practices (e.g., Renfrew, 1997; Diamond and Bellwood, 2003; Lee and Hasegawa, 2011) and cultural values (e.g., Currie et al., 2010; Bulbulia et al., 2013) can be inherited or borrowed. This means that the data may be composed of non-independent points, inflating the apparent correlation between rice growing and collectivism. The correlation between farming practices and collectivism may be robust, but this cannot be known without an empirical control for the relatedness of the samples. Talhelm et al. do discuss this problem in the supplementary materials of their paper. They acknowledge that a phylogenetic analysis could be used to control for relatedness, but that at the time of publication there were no genetic or linguistic trees of descent which are detailed enough to suit this purpose. In this commentary I would like to make two points. First, since the original publication, researchers have created new linguistic trees that can provide the needed resolution. For example, the Glottolog phylogeny (Hammarström et al., 2015) has at least three levels of classification for the relevant varieties, though this does not have branch lengths (see also “reference” trees produced in List et al., 2014). Another recently published phylogeny uses lexical data to construct a phylogenetic tree for many language varieties within China (List et al., 2014). In this commentary I use these lexical data to estimate cultural contact between different provinces, and test whether these measures explain variation in rice farming pracices. However, the second point is that Talhelm et al. focus on descent (vertical transmission), while it may be relevant to control for both descent and borrowing (horizontal transmission). In this case, all that is needed is some measure of cultural contact between groups, not necessarily a unified tree of descent. I use a second source of linguistic data to calculate simple distances between languages based directly on the lexicon. These distances reflect borrowing as well as descent.

Abstract

A previous study by Chen demonstrates a correlation between languages that grammatically mark future events and their speakers' propensity to save, even after controlling for numerous economic and demographic factors. The implication is that languages which grammatically distinguish the present and the future may bias their speakers to distinguish them psychologically, leading to less future-oriented decision making. However, Chen's original analysis assumed languages are independent. This neglects the fact that languages are related, causing correlations to appear stronger than is warranted (Galton's problem). In this paper, we test the robustness of Chen's correlations to corrections for the geographic and historical relatedness of languages. While the question seems simple, the answer is complex. In general, the statistical correlation between the two variables is weaker when controlling for relatedness. When applying the strictest tests for relatedness, and when data is not aggregated across individuals, the correlation is not significant. However, the correlation did remain reasonably robust under a number of tests. We argue that any claims of synchronic patterns between cultural variables should be tested for spurious correlations, with the kinds of approaches used in this paper. However, experiments or case-studies would be more fruitful avenues for future research on this specific topic, rather than further large-scale cross-cultural correlational studies.

Abstract

We suggest that it is now possible to conduct research on a topic which might be called evolutionary geophonetics. The main question is how the climate influences the evolution of language. This involves biological adaptations to the climate that may affect biases in production and perception; cultural evolutionary adaptations of the sounds of a language to climatic conditions; and influences of the climate on language diversity and contact. We discuss these ideas with special reference to a recent hypothesis that lexical tone is not adaptive in dry climates (Everett, Blasi & Roberts, 2015).