Publications

Abstract

Recent proposals hold that the cognitive systems underlying language production exhibit computational properties that facilitate communicative efficiency, i.e., an efficient trade-off between production ease and robust information transmission. We contribute to the cross-linguistic evaluation of the communicative efficiency hypothesis by investigating speakers’ preferences in the production of a typologically rare head-marking alternation that occurs in relative clause constructions in Yucatec Maya. In a sentence recall study, we find that speakers of Yucatec Maya prefer to use reduced forms of relative clause verbs when the relative clause is more contextually expected. This result is consistent with communicative efficiency and thus supports its typological generalizability. We compare two types of cue to the presence of a relative clause, pragmatic cues previously investigated in other languages and a highly predictive morphosyntactic cue specific to Yucatec. We find that Yucatec speakers’ preferences for a reduced verb form are primarily conditioned on the more informative cue. This demonstrates the role of both general principles of language production and their language-specific realizations.

Abstract

Spoken utterances contain few reliable cues to word boundaries, but listeners nonetheless experience little difficulty identifying words in continuous speech. The authors present data and simulations that suggest that this ability is best accounted for by a model of spoken-word recognition combining competition between alternative lexical candidates and sensitivity to prosodic structure. In a word-spotting experiment, stress pattern effects emerged most clearly when there were many competing lexical candidates for part of the input. Thus, competition between simultaneously active word candidates can modulate the size of prosodic effects, which suggests that spoken-word recognition must be sensitive both to prosodic structure and to the effects of competition. A version of the Shortlist model ( D. G. Norris, 1994b) incorporating the Metrical Segmentation Strategy ( A. Cutler & D. Norris, 1988) accurately simulates the results using a lexicon of more than 25,000 words.

Abstract

The central thesis of the target article was that feedback is never necessary in spoken word recognition. The commentaries present no new data and no new theoretical arguments which lead us to revise this position. In this response we begin by clarifying some terminological issues which have lead to a number of significant misunderstandings. We provide some new arguments to support our case that the feedforward model Merge is indeed more parsimonious than the interactive alternatives, and that it provides a more convincing account of the data than alternative models. Finally, we extend the arguments to deal with new issues raised by the commentators such as infant speech perception and neural architecture.

Abstract

Top-down feedback does not benefit speech recognition; on the contrary, it can hinder it. No experimental data imply that feedback loops are required for speech recognition. Feedback is accordingly unnecessary and spoken word recognition is modular. To defend this thesis, we analyse lexical involvement in phonemic decision making. TRACE (McClelland & Elman 1986), a model with feedback from the lexicon to prelexical processes, is unable to account for all the available data on phonemic decision making. The modular Race model (Cutler & Norris 1979) is likewise challenged by some recent results, however. We therefore present a new modular model of phonemic decision making, the Merge model. In Merge, information flows from prelexical processes to the lexicon without feedback. Because phonemic decisions are based on the merging of prelexical and lexical information, Merge correctly predicts lexical involvement in phonemic decisions in both words and nonwords. Computer simulations show how Merge is able to account for the data through a process of competition between lexical hypotheses. We discuss the issue of feedback in other areas of language processing and conclude that modular models are particularly well suited to the problems and constraints of speech recognition.

Abstract

Speech perception involves prediction, but how is that prediction implemented? In cognitive models prediction has often been taken to imply that there is feedback of activation from lexical to pre-lexical processes as implemented in interactive-activation models (IAMs). We show that simple activation feedback does not actually improve speech recognition. However, other forms of feedback can be beneficial. In particular, feedback can enable the listener to adapt to changing input, and can potentially help the listener to recognise unusual input, or recognise speech in the presence of competing sounds. The common feature of these helpful forms of feedback is that they are all ways of optimising the performance of speech recognition using Bayesian inference. That is, listeners make predictions about speech because speech recognition is optimal in the sense captured in Bayesian models.

Abstract

Educational attainment is strongly influenced by social and other environmental factors, but genetic factors are estimated to account for at least 20% of the variation across individuals. Here we report the results of a genome-wide association study (GWAS) for educational attainment that extends our earlier discovery sample of 101,069 individuals to 293,723 individuals, and a replication study in an independent sample of 111,349 individuals from the UK Biobank. We identify 74 genome-wide significant loci associated with the number of years of schooling completed. Single-nucleotide polymorphisms associated with educational attainment are disproportionately found in genomic regions regulating gene expression in the fetal brain. Candidate genes are preferentially expressed in neural tissue, especially during the prenatal period, and enriched for biological pathways involved in neural development. Our findings demonstrate that, even for a behavioural phenotype that is mostly environmentally determined, a well-powered GWAS identifies replicable associated genetic variants that suggest biologically relevant pathways. Because educational attainment is measured in large numbers of individuals, it will continue to be useful as a proxy phenotype in efforts to characterize the genetic influences of related phenotypes, including cognition and neuropsychiatric diseases

Abstract

The sense of smell has widely been viewed as inferior to the other senses. This is reflected in the lack of treatment of olfaction in ethnographies and linguistic descriptions. We present novel data
from the olfactory lexicon of Seri, a language isolate of Mexico, which sheds new light onto the possibilities for olfactory terminologies. We also present the Seri smellscape, highlighting the cultural significance of odors in Seri culture which, along with the olfactory language, is now
under threat as globalization takes hold and traditional ways of life are transformed.

Abstract

Individual differences in aggressive behavior emerge in early childhood and predict persisting behavioral problems and disorders. Studies of antisocial and severe aggression in adulthood indicate substantial underlying biology. However, little attention has been given to genome-wide approaches of aggressive behavior in children. We analyzed data from nine population-based studies and assessed aggressive behavior using well-validated parent-reported questionnaires. This is the largest sample exploring children's aggressive behavior to date (N = 18,988), with measures in two developmental stages (N = 15,668 early childhood and N = 16,311 middle childhood/early adolescence). First, we estimated the additive genetic variance of children's aggressive behavior based on genome-wide SNP information, using genome-wide complex trait analysis (GCTA). Second, genetic associations within each study were assessed using a quasi-Poisson regression approach, capturing the highly right-skewed distribution of aggressive behavior. Third, we performed meta-analyses of genome-wide associations for both the total age-mixed sample and the two developmental stages. Finally, we performed a gene-based test using the summary statistics of the total sample. GCTA quantified variance tagged by common SNPs (10–54%). The meta-analysis of the total sample identified one region in chromosome 2 (2p12) at near genome-wide significance (top SNP rs11126630, P = 5.30 × 10−8). The separate meta-analyses of the two developmental stages revealed suggestive evidence of association at the same locus. The gene-based analysis indicated association of variation within AVPR1A with aggressive behavior. We conclude that common variants at 2p12 show suggestive evidence for association with childhood aggression. Replication of these initial findings is needed, and further studies should clarify its biological meaning.

Abstract

In a shooting video game we investigated whether increased distance reduces moral conflict. We measured and analyzed the event related potential (ERP), including the N2 component, which has previously been linked to cognitive conflict from competing decision tendencies. In a modified Go/No-go task designed to trigger moral conflict participants had to shoot suddenly appearing human like avatars in a virtual reality scene. The scene was seen either from an ego perspective with targets appearing directly in front of the participant or from a bird's view, where targets were seen from above and more distant. To control for low level visual features, we added a visually identical control condition, where the instruction to shoot was replaced by an instruction to detect. ERP waveforms showed differences between the two tasks as early as in the N1 time-range, with higher N1 amplitudes for the close perspective in the shoot task. Additionally, we found that pre-stimulus alpha power was significantly decreased in the ego, compared to the bird's view only for the shoot but not for the detect task. In the N2 time window, we observed main amplitude effects for response (No-go > Go) and distance (ego > bird perspective) but no interaction with task type (shoot vs. detect). We argue that the pre-stimulus and N1 effects can be explained by reduced attention and arousal in the distance condition when people are instructed to shoot. These results indicate a reduced moral engagement for increased distance. The lack of interaction in the N2 across tasks suggests that at that time point response execution dominates. We discuss potential implications for real life shooting situations, especially considering recent developments in drone shootings which are per definition of a distant view.

Abstract

It has previously been suggested that the activity in sensory regions of the brain can be modulated by attentional mechanisms during parallel cognitive processing. To investigate whether such attention-related modulations are present in the processing of pain, the regional cerebral blood ¯ow was measured using [15O]butanol and positron emission tomography in conditions involving both pain and parallel cognitive demands. The painful stimulus consisted of the standard cold pressor test and the cognitive task was a computerised perceptual maze test. The activations during the maze test reproduced findings in previous studies of the same cognitive task. The cold pressor test evoked signi®cant activity in the contralateral S1, and bilaterally in the somatosensory association areas (including S2), the ACC and the mid-insula. The activity in the somatosensory association areas and periaqueductal gray/midbrain were significantly modified, i.e. relatively decreased, when the subjects also were performing the maze task. The altered activity was accompanied with significantly lower ratings of pain during the cognitive task. In contrast, lateral orbitofrontal regions showed a relative increase of activity during pain combined with the maze task as compared to only pain, which suggests the possibility of the involvement of frontal cortex in modulation of regions processing pain

Abstract

In this paper hypothesis‐testing behaviour is compared to risk‐taking behaviour. It is proposed that choosing a suitable test for a given hypothesis requires making a preposterior analysis of two aspects of such a test: the probability of obtaining supporting evidence and the evidential value of this evidence. This consideration resembles the one a gambler makes when choosing among bets, each having a probability of winning and an amount to be won. A confirmatory testing strategy can be defined within this framework as a strategy directed at maximizing either the probability or the value of a confirming outcome. Previous theories on testing behaviour have focused on the human tendency to maximize the probability of a confirming outcome. In this paper, two experiments are presented in which participants tend to maximize the confirming value of the test outcome. Motivational factors enhance this tendency dependent on the context of the testing situation. Both this result and the framework are discussed in relation to other studies in the field of testing behaviour.

Abstract

Rey et al. (2012) present data from a study with baboons that they interpret in support of the idea that center-embedded structures in human language have their origin in low level memory mechanisms and associative learning. Critically, the authors claim that the baboons showed a behavioral preference that is consistent with center-embedded sequences over other types of sequences. We argue that the baboons’ response patterns suggest that two mechanisms are involved: first, they can be trained to associate a particular response with a particular stimulus, and, second, when faced with two conditioned stimuli in a row, they respond to the most recent one first, copying behavior they had been rewarded for during training. Although Rey et al. (2012) ‘experiment shows that the baboons’ behavior is driven by low level mechanisms, it is not clear how the animal behavior reported, bears on the phenomenon of Center Embedded structures in human syntax. Hence, (1) natural language syntax may indeed have been shaped by low level mechanisms, and (2) the baboons’ behavior is driven by low level stimulus response learning, as Rey et al. propose. But is the second evidence for the first? We will discuss in what ways this study can and cannot give evidential value for explaining the origin of Center Embedded recursion in human grammar. More generally, their study provokes an interesting reflection on the use of animal studies in order to understand features of the human linguistic system.

Abstract

This experiment shows that recent experience in one language influences subsequent processing of the same word-forms in a different language. Dutch–English bilinguals read Dutch sentences containing Dutch–English cognates and interlingual homographs, which were presented again 16 minutes later in isolation in an English lexical decision task. Priming produced faster responses for the cognates but slower responses for the interlingual homographs. These results show that language switching can influence bilingual speakers at the level of individual words, and require models of bilingual word recognition (e.g., BIA+) to allow access to word meanings to be modulated by recent experience.

Abstract

We investigated whether augmenting instructional animations with a body analogy (BA) would improve 10- to 13-year-old children’s learning about class-1 levers. Children with a lower level of general math skill who learned with an instructional animation that provided a BA of the physical system, showed higher accuracy on a lever problem-solving reaction time task than children studying the instructional animation without this BA. Additionally, learning with a BA led to a higher speed–accuracy trade-off during the transfer task for children with a lower math skill, which provided additional evidence that especially this group is likely to be affected by learning with a BA. However, overall accuracy and solving speed on the transfer task was not affected by learning with or without this BA. These results suggest that providing children with a BA during animation study provides a stepping-stone for understanding mechanical principles of a physical system, which may prove useful for instructional designers. Yet, because the BA does not seem effective for all children, nor for all tasks, the degree of effectiveness of body analogies should be studied further. Future research, we conclude, should be more sensitive to the necessary degree of analogous mapping between the body and physical systems, and whether this mapping is effective for reasoning about more complex instantiations of such physical systems.

Abstract

Previous research indicates that sensori‐motor experience with physical systems can have a positive effect on learning. However, it is not clear whether this effect is caused by mere bodily engagement or the intrinsically meaningful information that such interaction affords in performing the learning task. We investigated (N = 74), through the use of a Wii Balance Board, whether different forms of physical engagement that was either meaningfully, non‐meaningfully, or minimally related to the learning content would be beneficial (or detrimental) to learning about the workings of seesaws from instructional animations. The results were inconclusive, indicating that motoric competency on lever problem solving did not significantly differ between conditions, nor were response speed and transfer performance affected. These findings suggest that adult's implicit and explicit knowledge about physical systems is stable and not easily affected by (contradictory) sensori‐motor experiences. Implications for embodied learning are discussed.

Abstract

Two broad approaches have dominated the literature on the production of speech-accompanying gestures. On the one hand, there are approaches that aim to explain the origin of gestures by specifying the mental processes that give rise to them. On the other, there are approaches that aim to explain the cognitive function that gestures have for the gesturer or the listener. In the present paper we aim to reconcile both approaches in one single perspective that is informed by a recent sea change in cognitive science, namely, Predictive Processing Perspectives (PPP; Clark 2013b; 2015). We start with the idea put forth by the Gesture as Simulated Action (GSA) framework (Hostetter, Alibali 2008). Under this view, the mental processes that give rise to gesture are re-enactments of sensori-motor experiences (i.e., simulated actions). We show that such anticipatory sensori-motor states and the constraints put forth by the GSA framework can be understood as top-down kinesthetic predictions that function in a broader predictive machinery as proposed by PPP. By establishing this alignment, we aim to show how gestures come to fulfill a genuine cognitive function above and beyond the mental processes that give rise to gesture.

Abstract

Non-communicative hand gestures have been found to benefit problem-solving performance. These gestures seem to compensate for limited internal cognitive capacities, such as visual working memory capacity. Yet, it is not clear how gestures might perform this cognitive function. One hypothesis is that gesturing is a means to spatially index mental simulations, thereby reducing the need for visually projecting the mental simulation onto the visual presentation of the task. If that hypothesis is correct, less eye movements should be made when participants gesture during problem solving than when they do not gesture. We therefore used mobile eye tracking to investigate the effect of co-thought gesturing and visual working memory capacity on eye movements during mental solving of the Tower of Hanoi problem. Results revealed that gesturing indeed reduced the number of eye movements (lower saccade counts), especially for participants with a relatively lower visual working memory capacity. Subsequent problem-solving performance was not affected by having (not) gestured during the mental solving phase. The current findings suggest that our understanding of gestures in problem solving could be improved by taking into account eye movements during gesturing.

Abstract

A patient who already had Wernick's aphasia due to a left temporal lobe lesion suffered a severe deterioration specifically of auditory language comprehension, subsequent to right temporal lobe infarction. A detailed comparison of his new condition with his language status before the second stroke revealed that the newly acquired deficit was limited to tasks related to auditory input. Further investigations demonstrated a speech perceptual disorder, which we analysed as due to deficits both at the level of general auditory processes and at the level of phonetic analysis. We discuss some arguments related to hemisphere specialization of phonetic processing and to the disconnection explanation of word deafness that support the hypothesis of word deafness being generally caused by mixed deficits.

Abstract

Linguistic communication builds on prelinguistic communicative gestures, but the ontogenetic origins and complexities of these prelinguistic gestures are not well known. The current study tested whether 8-month-olds, who do not yet point communicatively, use instrumental actions for communicative purposes. In two experiments, infants reached for objects when another person was present and when no one else was present; the distance to the objects was varied. When alone, the infants reached for objects within their action boundaries and refrained from reaching for objects out of their action boundaries; thus, they knew about their individual action efficiency. However, when a parent (Experiment 1) or a less familiar person (Experiment 2) sat next to them, the infants selectively increased their reaching for out-of-reach objects. The findings reveal that before they communicate explicitly through pointing gestures, infants use instrumental actions with the apparent expectation that a partner will adopt and complete their goals.

Abstract

Music exhibits some cross-cultural similarities, despite its variety across the world. Evidence from a broad range of human cultures suggests the existence of musical universals1, here defined as strong regularities emerging across cultures above chance. In particular, humans demonstrate a general proclivity for rhythm2, although little is known about why music is particularly rhythmic and why the same structural regularities are present in rhythms around the world. We empirically investigate the mechanisms underlying musical universals for rhythm, showing how music can evolve culturally from randomness. Human participants were asked to imitate sets of randomly generated drumming sequences and their imitation attempts became the training set for the next participants in independent transmission chains. By perceiving and imitating drumming sequences from each other, participants turned initially random sequences into rhythmically structured patterns. Drumming patterns developed into rhythms that are more structured, easier to learn, distinctive for each experimental cultural tradition and characterized by all six statistical universals found among world music1; the patterns appear to be adapted to human learning, memory and cognition. We conclude that musical rhythm partially arises from the influence of human cognitive and biological biases on the process of cultural evolution.

Abstract

Recently psychologists have taken up the question of whether dance is reliant on unique human adaptations, or whether it is rooted in neural and cognitive mechanisms shared with other species 1, 2. In its full cultural complexity, human dance clearly has no direct analog in animal behavior. Most definitions of dance include the consistent production of movement sequences timed to an external rhythm. While not sufficient for dance, modes of auditory-motor timing, such as synchronization and entrainment, are experimentally tractable constructs that may be analyzed and compared between species. In an effort to assess the evolutionary precursors to entrainment and social features of human dance, Laland and colleagues [2] have suggested that dance may be an incidental byproduct of adaptations supporting vocal or motor imitation — referred to here as the ‘imitation and sequencing’ hypothesis. In support of this hypothesis, Laland and colleagues rely on four convergent lines of evidence drawn from behavioral and neurobiological research on dance behavior in humans and rhythmic behavior in other animals. Here, we propose a less cognitive, more parsimonious account for the evolution of dance. Our ‘timing and interaction’ hypothesis suggests that dance is scaffolded off of broadly conserved timing mechanisms allowing both cooperative and antagonistic social coordination.

Abstract

Research on the evolution of human speech and music benefits from hypotheses and data generated in a number of disciplines. The purpose of this article is to illustrate the high relevance of pinniped research for the study of speech, musical rhythm, and their origins, bridging and complementing current research on primates and birds. We briefly discuss speech, vocal learning, and rhythm from an evolutionary and comparative perspective. We review the current state of the art on pinniped communication and behavior relevant to the evolution of human speech and music, showing interesting parallels to hypotheses on rhythmic behavior in early hominids. We suggest future research directions in terms of species to test and empirical data needed.

Abstract

Adults prefer to interact with others that are similar to themselves. Even slight facial self-resemblance can elicit trust towards strangers. Here we investigate if preschoolers at the age of 5 years already use facial self-resemblance when they make social judgments about others. We found that, in the absence of any additional knowledge about prospective peers, children preferred those who look subtly like themselves over complete strangers. Thus, subtle morphological similarities trigger social preferences well before adulthood.

Abstract

The impact of introducing double-blind reviewing in the most recent Evolution of Language conference is assessed. The ranking of papers is compared between EvoLang 11 (double-blind review) and EvoLang 9 and 10 (single-blind review). Main effects were found for first author gender by conference. The results mirror some findings in the literature on the effects of double-blind review, suggesting that it helps reduce a bias against female authors.

Abstract

Almost all genetic risk factors for autism spectrum disorders (ASDs) can be found in the general population, but the effects of this risk are unclear in people not ascertained for neuropsychiatric symptoms. Using several large ASD consortium and population-based resources (total n > 38,000), we find genome-wide genetic links between ASDs and typical variation in social behavior and adaptive functioning. This finding is evidenced through both LD score correlation and de novo variant analysis, indicating that multiple types of genetic risk for ASDs influence a continuum of behavioral and developmental traits, the severe tail of which can result in diagnosis with an ASD or other neuropsychiatric disorder. A continuum model should inform the design and interpretation of studies of neuropsychiatric disease biology.

Abstract

Background Heterozygous mutations in CNTNAP2 have been identified in patients with a range of complex phenotypes including intellectual disability, autism and schizophrenia. However heterozygous CNTNAP2 mutations are also found in the normal population. Conversely, homozygous mutations are rare in patient populations and have not been found in any unaffected individuals. Case presentation We describe a consanguineous family carrying a deletion in CNTNAP2 predicted to abolish function of its protein product, CASPR2. Homozygous family members display epilepsy, facial dysmorphisms, severe intellectual disability and impaired language. We compared these patients with previously reported individuals carrying homozygous mutations in CNTNAP2 and identified a highly recognisable phenotype. Conclusions We propose that CASPR2 loss produces a syndrome involving early-onset refractory epilepsy, intellectual disability, language impairment and autistic features that can be recognized as CASPR2 deficiency disorder. Further screening for homozygous patients meeting these criteria, together with detailed phenotypic and molecular investigations will be crucial for understanding the contribution of CNTNAP2 to normal and disrupted development.

Abstract

Disagreement exists about how bilingual speakers select words, in particular, whether words in another language compete, or competition is restricted to a target language, or no competition occurs. Evidence that competition occurs but is restricted to a target language comes from response time (RT) effects obtained when speakers name pictures in one language while trying to ignore distractor words in another language. Compared to unrelated distractor words, RT is longer when the picture name and distractor are semantically related, but RT is shorter when the distractor is the translation of the name of the picture in the other language. These effects suggest that distractor words from another language do not compete themselves but activate their counterparts in the target language, thereby yielding the semantic interference and translation facilitation effects. Here, we report an event-related brain potential (ERP) study testing the prediction that priming underlies both of these effects. The RTs showed semantic interference and translation facilitation effects. Moreover, the picture-word stimuli yielded an N400 response, whose amplitude was smaller on semantic and translation trials than on unrelated trials, providing evidence that interference and facilitation priming underlie the RT effects. We present the results of computer simulations showing the utility of a within-language competition account of our findings.

Abstract

Not long after the premiere of Loxoro in 2011, a short-film by Claudia Llosa which presents the problems the transgender community faces in the capital of Peru, a new language variety became visible for the first time to the Lima society. Lóxoro [‘lok.so.ɾo] or Húngaro [‘uŋ.ga.ɾo], as its speakers call it, is a language spoken by transsexuals and the gay community of Peru. The first clues about its existence were given by a comedian, Fernando Armas, in the mid 90’s, however it is said to have appeared not before the 60’s. Following some previous work on gay languages by Baker (2002) and languages and society (cf. Halliday 1978), the main aim of the present article is to provide a primary sketch of this language in its phonological, morphological, lexical and sociological aspects, based on a small corpus extracted from the film of Llosa and natural dialogues from Peruvian TV-journals, in order to classify this variety within modern sociolinguistic models (cf. Muysken 2010) and argue for the “anti-language” (cf. Halliday 1978) nature of it

Abstract

Sentence and construction types generally have more than one pragmatic function. Impersonal deontic declaratives such as ‘it is necessary to X’ assert the existence of an obligation or necessity without tying it to any particular individual. This family of statements can accomplish a range of functions, including getting another person to act, explaining or justifying the speaker’s own behavior as he or she undertakes to do something, or even justifying the speaker’s behavior while simultaneously getting another person to help. How is an impersonal deontic declarative fit for these different functions? And how do people know which function it has in a given context? We address these questions using video recordings of everyday interactions among speakers of Italian and Polish. Our analysis results in two findings. The first is that the pragmatics of impersonal deontic declaratives is systematically shaped by (i) the relative responsibility of participants for the necessary task and (ii) the speaker’s nonverbal conduct at the time of the statement. These two factors influence whether the task in question will be dealt with by another person or by the speaker, often giving the statement the force of a request or, alternatively, of an account of the speaker’s behavior. The second finding is that, although these factors systematically influence their function, impersonal deontic declaratives maintain the potential to generate more complex interactions that go beyond a simple opposition between requests and accounts, where participation in the necessary task may be shared, negotiated, or avoided. This versatility of impersonal deontic declaratives derives from their grammatical makeup: by being deontic and impersonal, they can both mobilize or legitimize an act by different participants in the speech event, while their declarative form does not constrain how they should be responded to. These features make impersonal deontic declaratives a special tool for the management of social agency.

Abstract

Objective

Despite the need for effective pain communication, pain is difficult to verbalise. Co-speech gestures frequently add information about pain that is not contained in the accompanying speech. We explored whether recipients can obtain additional information from gestures about the pain that is being described.
Methods

Participants (n = 135) viewed clips of pain descriptions under one of four conditions: 1) Speech Only; 2) Speech and Gesture; 3) Speech, Gesture and Face; and 4) Speech, Gesture and Face plus Instruction (short presentation explaining the pain information that gestures can depict). Participants provided free-text descriptions of the pain that had been described. Responses were scored for the amount of information obtained from the original clips.
Findings

Participants in the Instruction condition obtained the most information, while those in the Speech Only condition obtained the least (all comparisons p<.001).
Conclusions

Gestures produced during pain descriptions provide additional information about pain that recipients are able to pick up without detriment to their uptake of spoken information.
Practice implications

Healthcare professionals may benefit from instruction in gestures to enhance uptake of information about patients’ pain experiences.

Abstract

The present paper reports an analysis of correct wh-question production and subject–auxiliary inversion errors in one child's early wh-question data (age 2; 3.4 to 4; 10.23). It is argued that two current movement rule accounts (DeVilliers, 1991; Valian, Lasser & Mandelbaum, 1992) cannot explain the patterning of early wh-questions. However, the data can be explained in terms of the child's knowledge of particular lexically-specific wh-word+auxiliary combinations, and the pattern of inversion and uninversion predicted from the relative frequencies of these combinations in the mother's speech. The results support the claim that correctly inverted wh-questions can be produced without access to a subject–auxiliary inversion rule and are consistent with the constructivist claim that a distributional learning mechanism that learns and reproduces lexically-specific formulae heard in the input can explain much of the early multi-word speech data. The implications of these results for movement rule-based and constructivist theories of grammatical development are discussed.

Abstract

Carston (2010) proposes that metaphors can be processed via two different routes. In line with the standard Relevance-Theoretic account of loose use, single metaphors are interpreted by a local pragmatic process of meaning adjustment, resulting in the construction of an ad hoc concept. In extended metaphorical passages, by contrast, the reader switches to a second processing mode because the various semantic associates in the passage are mutually reinforcing, which makes the literal meaning highly activated relative to possible meaning adjustments. In the second processing mode the literal meaning of the whole passage is metarepresented and entertained as an ‘imaginary world’ and the intended figurative implications are derived later in processing. The results of three experiments comparing the interpretation of the same target expressions across literal, single-metaphorical and extended-metaphorical contexts, using self-paced reading (Experiment 1), eye-tracking during natural reading (Experiment 2) and cued recall (Experiment 3), offered initial support to Carston's distinction between the processing of single and extended metaphors. We end with a comparison between extended metaphors and allegories, and make a call for further theoretical and experimental work to increase our understanding of the similarities and differences between the interpretation and processing of different figurative uses, single and extended.

Abstract

Color adjectives tend to be used redundantly in referential communication. I propose that redundant color adjectives (RCAs) are often intended to exploit a color contrast in the visual context and hence facilitate object identification, despite not being necessary to establish unique reference. Two language-production experiments investigated two types of factors that may affect the use of RCAs: factors related to the efficiency of color in the visual context and factors related to the semantic category of the noun. The results of Experiment 1 confirmed that people produce RCAs when color may facilitate object recognition; e.g., they do so more often in polychrome displays than in monochrome displays, and more often in English (pre-nominal position) than in Spanish (post-nominal position). RCAs are also used when color is a central property of the object category; e.g., people referred to the color of clothes more often than to the color of geometrical figures (Experiment 1), and they overspecified atypical colors more often than variable and stereotypical colors (Experiment 2). These results are relevant for pragmatic models of referential communication based on Gricean pragmatics and informativeness. An alternative analysis is proposed, which focuses on the efficiency and pertinence of color in a given referential situation.

Abstract

This study investigates the development of two cognitive abilities that are involved in metaphor comprehension: implicit analogical reasoning and assigning an unconventional label to a familiar entity (as in Romeo’s ‘Juliet is the sun’). We presented 3- and 4-year-old children with literal object-requests in a pretense setting (e.g., ‘Give me the train with the hat’). Both age-groups succeeded in a baseline condition that used building blocks as props (e.g., placed either on the front or the rear of a train engine) and only required spatial analogical reasoning to interpret the referential expression. Both age-groups performed significantly worse in the critical condition, which used familiar objects as props (e.g., small dogs as pretend hats) and required both implicit analogical reasoning and assigning second labels. Only the 4-year olds succeeded in this condition. These results offer a new perspective on young children’s difficulties with metaphor comprehension in the preschool years.

Abstract

Despite their central role in question formation, content interrogatives in spontaneous conversation remain relatively under-explored cross-linguistically. This paper outlines the structure of ‘where’ expressions in Duna, a language spoken in Papua New Guinea, and examines where-questions in a small Duna data set in terms of their frequency, function, and the responses they elicit. Questions that ask ‘where?’ have been identified as a useful tool in studying the language of space and place, and, in the Duna case and elsewhere, show high frequency and functional flexibility. Although where-questions formulate place as an information gap, they are not always answered through direct reference to canonical places. While some question types may be especially “socially costly” (Levinson 2012), asking ‘where’ perhaps provides a relatively innocuous way of bringing a particular event or situation into focus.

Abstract

In the last few decades little to nothing has been said about the sociolinguistic situation of Yumanan languages in Mexico. In order to cope with this lack of studies, we present a first study on linguistic vitality in Paipai, as it is spoken in Santa Catarina, Baja California, Mexico. Since languages such as Mexican Spanish and Ko’ahl coexist with this language in the same ecology, both are part of the study as well. This first approach hoists from two axes: on one hand, providing a theoretical framework that explains the sociolinguistic dynamics in the ecology of the language (Mufwene 2001), and, on the other hand, bringing over a quantitative study based on MSF (Maximum Shared Facility) (Terborg & Garcìa 2011), which explains the state of linguistic vitality of paipai, enriched by qualitative information collected in situ

Abstract

Capacity limited memory systems need to gradually forget old information in order to avoid catastrophic forgetting where all stored information is lost. This can be achieved by allowing new information to overwrite old, as in the so-called palimpsest memory. This paper describes a new such learning rule employed in an attractor neural network. The network does not exhibit catastrophic forgetting, has a capacity dependent on the learning time constant and exhibits recency e!ects in retrieval

Abstract

Experimental research on behavior and cognition frequently rests on stimulus or subject selection where not all characteristics can be fully controlled, even when attempting strict matching. For example, when contrasting patients to controls, variables such as intelligence or socioeconomic status are often correlated with patient status. Similarly, when presenting word stimuli, variables such as word frequency are often correlated with primary variables of interest. One procedure very commonly employed to control for such nuisance effects is conducting inferential tests on confounding stimulus or subject characteristics. For example, if word length is not significantly different for two stimulus sets, they are considered as matched for word length. Such a test has high error rates and is conceptually misguided. It reflects a common misunderstanding of statistical tests: interpreting significance not to refer to inference about a particular population parameter, but about 1. the sample in question, 2. the practical relevance of a sample difference (so that a nonsignificant test is taken to indicate evidence for the absence of relevant differences). We show inferential testing for assessing nuisance effects to be inappropriate both pragmatically and philosophically, present a survey showing its high prevalence, and briefly discuss an alternative in the form of regression including nuisance variables.

Abstract

Studies on anticipatory processes during sentence comprehension often focus on the prediction of postverbal direct objects. In subject-initial languages (the target of most studies so far), however, the position in the sentence, the syntactic function, and the semantic role of arguments are often conflated. For example, in the sentence “The frog will eat the fly” the syntactic object (“fly”) is at the same time also the last word and the patient argument of the verb. It is therefore not apparent which kind of information listeners orient to for predictive processing during sentence comprehension. A visual world eye tracking study on the verb-initial language Tagalog (Austronesian) tested what kind of information listeners use to anticipate upcoming postverbal linguistic input. The grammatical structure of Tagalog allows to test whether listeners' anticipatory gaze behavior is guided by predictions of the linear order of words, by syntactic functions (e.g., subject/object), or by semantic roles (agent/patient). Participants heard sentences of the type “Eat frog fly” or “Eat fly frog” (both meaning “The frog will eat the fly”) while looking at displays containing an agent referent (“frog”), a patient referent (“fly”) and a distractor. The verb carried morphological marking that allowed the order and syntactic function of agent and patient to be inferred. After having heard the verb, listeners fixated on the agent irrespective of its syntactic function or position in the sentence. While hearing the first-mentioned argument, listeners fixated on the corresponding referent in the display accordingly and then initiated saccades to the last-mentioned referent before it was encountered. The results indicate that listeners used verbal semantics to identify referents and their semantic roles early; information about word order or syntactic functions did not influence anticipatory gaze behavior directly after the verb was heard. In this verb-initial language, event semantics takes early precedence during the comprehension of sentences, while arguments are anticipated temporally more local to when they are encountered. The current experiment thus helps to better understand anticipation during language processing by employing linguistic structures not available in previously studied subject-initial languages.

Abstract

Many people speak more than two languages. How do languages acquired earlier affect the learnability of additional languages? We show that linguistic distances between speakers' first (L1) and second (L2) languages and their third (L3) language play a role. Larger distances from the L1 to the L3 and from the L2 to the L3 correlate with lower degrees of L3 learnability. The evidence comes from L3 Dutch speaking proficiency test scores obtained by candidates who speak a diverse set of L1s and L2s. Lexical and morphological distances between the L1s of the learners and Dutch explained 47.7% of the variation in proficiency scores. Lexical and morphological distances between the L2s of the learners and Dutch explained 32.4% of the variation in proficiency scores in multilingual learners. Cross-linguistic differences require language learners to bridge varying linguistic gaps between their L1 and L2 competences and the target language.

Abstract

Normal-hearing listeners use acoustic cues in speech to interpret a speaker's emotional state. This study investigates the effect of hearing aids on the perception of the emotion dimensions arousal (aroused/calm) and valence (positive/negative attitude) in older adults with hearing loss. More specifically, we investigate whether wearing a hearing aid improves the correlation between affect ratings and affect-related acoustic parameters. To that end, affect ratings by 23 hearing-aid users were compared for aided and unaided listening. Moreover, these ratings were compared to the ratings by an age-matched group of 22 participants with age-normal hearing.For arousal, hearing-aid users rated utterances as generally more aroused in the aided than in the unaided condition. Intensity differences were the strongest indictor of degree of arousal. Among the hearing-aid users, those with poorer hearing used additional prosodic cues (i.e., tempo and pitch) for their arousal ratings, compared to those with relatively good hearing. For valence, pitch was the only acoustic cue that was associated with valence. Neither listening condition nor hearing loss severity (differences among the hearing-aid users) influenced affect ratings or the use of affect-related acoustic parameters. Compared to the normal-hearing reference group, ratings of hearing-aid users in the aided condition did not generally differ in both emotion dimensions. However, hearing-aid users were more sensitive to intensity differences in their arousal ratings than the normal-hearing participants.We conclude that the use of hearing aids is important for the rehabilitation of affect perception and particularly influences the interpretation of arousal

Abstract

This study investigated whether age and/or differences in hearing sensitivity influence the perception of the emotion dimensions arousal (calm vs. aroused) and valence (positive vs. negative attitude) in conversational speech. To that end, this study specifically focused on the relationship between participants' ratings of short affective utterances and the utterances' acoustic parameters (pitch, intensity, and articulation rate) known to be associated with the emotion dimensions arousal and valence. Stimuli consisted of short utterances taken from a corpus of conversational speech. In two rating tasks, younger and older adults either rated arousal or valence using a 5-point scale. Mean intensity was found to be the main cue participants used in the arousal task (i.e., higher mean intensity cueing higher levels of arousal) while mean F-0 was the main cue in the valence task (i.e., higher mean F-0 being interpreted as more negative). Even though there were no overall age group differences in arousal or valence ratings, compared to younger adults, older adults responded less strongly to mean intensity differences cueing arousal and responded more strongly to differences in mean F-0 cueing valence. Individual hearing sensitivity among the older adults did not modify the use of mean intensity as an arousal cue. However, individual hearing sensitivity generally affected valence ratings and modified the use of mean F-0. We conclude that age differences in the interpretation of mean F-0 as a cue for valence are likely due to age-related hearing loss, whereas age differences in rating arousal do not seem to be driven by hearing sensitivity differences between age groups (as measured by pure-tone audiometry).

Abstract

The way we talk can influence how we are perceived by others. Whereas previous studies have started to explore the influence of social goals on syntactic alignment, in the current study, we additionally investigated whether syntactic alignment effectively influences conversation partners’ perception of the speaker. To this end, we developed a novel paradigm in which we can measure the effect of social goals on the strength of syntactic alignment for one participant (primed participant), while simultaneously obtaining usable social opinions about them from their conversation partner (the evaluator). In Study 1, participants’ desire to be rated favorably by their partner was manipulated by assigning pairs to a Control (i.e., primed participants did not know they were being evaluated) or Evaluation context (i.e., primed participants knew they were being evaluated). Surprisingly, results showed no significant difference in the strength with which primed participants aligned their syntactic choices with their partners’ choices. In a follow-up study, we used a Directed Evaluation context (i.e., primed participants knew they were being evaluated and were explicitly instructed to make a positive impression). However, again, there was no evidence supporting the hypothesis that participants’ desire to impress their partner influences syntactic alignment. With respect to the influence of syntactic alignment on perceived likeability by the evaluator, a negative relationship was reported in Study 1: the more primed participants aligned their syntactic choices with their partner, the more that partner decreased their likeability rating after the experiment. However, this effect was not replicated in the Directed Evaluation context of Study 2. In other words, our results do not support the conclusion that speakers’ desire to be liked affects how much they align their syntactic choices with their partner, nor is there convincing evidence that there is a reliable relationship between syntactic alignment and perceived likeability.

Abstract

Verbal interaction is one of the most frequent social interactions humans encounter on a daily basis. In the current paper, we zoom in on what the multi-brain approach has contributed, and can contribute in the future, to our understanding of the neural mechanisms supporting verbal interaction. Indeed, since verbal interaction can only exist between individuals, it seems intuitive to focus analyses on inter-individual neural markers, i.e. between-brain neural coupling. To date, however, there is a severe lack of theoretically-driven, testable hypotheses about what between-brain neural coupling actually reflects. In this paper, we develop a testable hypothesis in which between-pair variation in between-brain neural coupling is of key importance. Based on theoretical frameworks and empirical data, we argue that the level of between-brain neural coupling reflects speaker-listener alignment at different levels of linguistic and extra-linguistic representation. We discuss the possibility that between-brain neural coupling could inform us about the highest level of inter-speaker alignment: mutual understanding

Abstract

We investigated whether structural priming of production latencies is sensitive to the same factors known to influence persistence of structural choices: structure preference, cumulativity and verb repetition. In two experiments, we found structural persistence only for passives (inverse preference effect) while priming effects on latencies were stronger for the actives (positive preference effect). We found structural persistence for passives to be influenced by immediate primes and long lasting cumulativity (all preceding primes) (Experiment 1), and to be boosted by verb repetition (Experiment 2). In latencies we found effects for actives were sensitive to long lasting cumulativity (Experiment 1). In Experiment 2, in latencies we found priming for actives overall, while for passives the priming effects emerged as the cumulative exposure increased but only when also aided by verb repetition. These findings are consistent with the Two-stage Competition model, an integrated model of structural priming effects for sentence choice and latency

Abstract

Schizophrenia is a complex disorder that affects cognitive function and has been linked, both in patients and animal models, to dysfunction of the GABAergic system. However, the pathophysiological consequences of this dysfunction are not well understood. Here, we examined the GABAergic system in an animal model displaying schizophrenia-relevant features, the apomorphine-susceptible (APO-SUS) rat and its phenotypic counterpart, the apomorphine-unsusceptible (APO-UNSUS) rat at postnatal day 20-22. We found changes in the expression of the GABA-synthesizing enzyme GAD67 specifically in the prelimbic-but not the infralimbic region of the medial prefrontal cortex (mPFC), indicative of reduced inhibitory function in this region in APO-SUS rats. While we did not observe changes in basal synaptic transmission onto LII/III pyramidal cells in the mPFC of APO-SUS compared to APO-UNSUS rats, we report reduced paired-pulse ratios at longer inter-stimulus intervals. The GABA(B) receptor antagonist CGP 55845 abolished this reduction, indicating that the decreased paired-pulse ratio was caused by increased GABA(B) signaling. Consistently, we find an increased expression of the GABA(B1) receptor subunit in APO-SUS rats. Our data provide physiological evidence for increased presynaptic GABAB signaling in the mPFC of APO-SUS rats, further supporting an important role for the GABAergic system in the pathophysiology of schizophrenia.

Abstract

The present study paints the intellectual environment in which Ferdinand de Saussure developed his ideas about language and linguistics during the fin de siècle. It sketches his dissatisfaction with that environment to the extent that it touched on linguistics, and shows the new course he was trying to steer on the basis of ideas that seemed to open new and exciting perspectives, even though they were still vaguely defined. As Saussure himself was extremely reticent about his sources and intellectual pedigree, his stance in the lively European cultural context in which he lived can only be established through textual critique and conjecture. On this basis, it is concluded that Saussure, though relatively uninformed about its historical roots, essentially aimed at integrating the rationalist tradition current in the sciences in his day into a new, ‘scientific’ general theory of language. In this, he was heavily indebted to a few predecessors, such as the French philosopher-psychologist Victor Egger, and particularly to the French psychologist, historian and philosopher Hippolyte Taine, who was a major cultural influence in nineteenth-century France, though now largely forgotten. The present study thus supports Hans Aarsleff's analysis, where, for the first time, Taine's influence is emphasised, and rejects John Joseph's contention that Taine had no influence and that, instead, Saussure was influenced mainly by the romanticist Adolphe Pictet. Saussure abhorred Pictet's method of etymologising, which predated the Young Grammarian school, central to Saussure's linguistic education. The issue has implications for the positioning of Saussure in the history of linguistics. Is he part of the non-analytical, romanticist and experience-based European strand of thought that is found in art and postmodernist philosophy and is sometimes called structuralism, or is he a representative of the short-lived European branch of specifically linguistic structuralism, which was rationalist in outlook, more science-oriented and more formalist, but lost out to American structuralism? The latter seems to be the case, though phenomenology, postmodernism and art have lately claimed Saussure as an icon

Abstract

The present study reports naming latencies and norms for 327 photos of objects in Dutch. We provide norms for eight psycholinguistic variables: age of acquisition, familiarity, imageability, image agreement, objective and subjective visual complexity, word frequency, word length in syllables and in letters, and name agreement. Furthermore, multiple regression analyses reveal that significant predictors of photo naming latencies are name agreement, word frequency, imageability, and image agreement. Naming latencies, norms and stimuli are provided as Supplemental Materials.

Abstract

A t(X;1)(p11.2;q21.2) has been reported in cases of papillary renal cell tumors arising in males. In this study two cell lines derived from this tumor type have been used to indicate the breakpoint region on the X chromosome. Both cell lines have the translocation in addition to other rearrangements and one is derived from the first female case to be reported with the t(X;1)(p11.2;q21.2). Fluorescence in situ hybridization (FISH) has been used to position YACs belonging to contigs in the Xp11.2 region relative to the breakpoint. When considered together with detailed mapping information from the Xp11.2 region the position of the breakpoint in both cell lines was suggested as follows: Xpter-->Xp11.23-OATL1-GATA1-WAS-TFE3-SY P-t(X;1)-DXS255-CLCN5-DXS146-OATL2- Xp11.22-->Xcen. The breakpoint was determined to lie in an uncloned region between SYP and a YAC called FTDM/1 which extends 1 Mb distal to DXS255. These results are contrary to the conclusion from previous FISH studies that the breakpoint was near the OATL2 locus, but are consistent with, and considerably refine, the position that had been established by molecular analysis.

Abstract

The colour-word Stroop task and the picture-word interference task (PWI) have been used extensively to study the functional processes underlying spoken word production. One of the consistent behavioural effects in both tasks is the Stroop-like effect: The reaction time (RT) is longer on incongruent trials than on congruent trials. The effect in the Stroop task is usually linked to word planning, whereas the effect in the PWI task is associated with either word planning or perceptual encoding. To adjudicate between the word planning and perceptual encoding accounts of the effect in PWI, we conducted an EEG experiment consisting of three tasks: a standard colour-word Stroop task (three colours), a standard PWI task (39 pictures), and a Stroop-like version of the PWI task (three pictures). Participants overtly named the colours and pictures while their EEG was recorded. A Stroop-like effect in RTs was observed in all three tasks. ERPs at centro-parietal sensors started to deflect negatively for incongruent relative to congruent stimuli around 350 ms after stimulus onset for the Stroop, Stroop-like PWI, and the Standard PWI tasks: an N400 effect. No early differences were found in the PWI tasks. The onset of the Stroop-like effect at about 350 ms in all three tasks links the effect to word planning rather than perceptual encoding, which has been estimated in the literature to be finished around 200–250 ms after stimulus onset. We conclude that the Stroop-like effect arises during word planning in both Stroop and PWI.

Abstract

Previous studies have provided evidence that updating, inhibiting, and shifting abilities underlying executive control determine response time (RT) in language production. However, little is known about their electrophysiological basis and dynamics. In the present electroencephalography study, we assessed noun-phrase production using picture description and a picture-word interference paradigm. We measured picture description RTs to assess length, distractor, and switch effects, which have been related to the updating, inhibiting, and shifting abilities. In addition, we measured event-related brain potentials (ERPs). Previous research has suggested that inhibiting and shifting are associated with anterior and posterior N200 subcomponents, respectively, and updating with the P300. We obtained length, distractor, and switch effects in the RTs, and an interaction between length and switch. There was a widely distributed switch effect in the N200, an interaction of length and midline site in the N200, and a length effect in the P300, whereas distractor did not yield any ERP modulation. Moreover, length and switch interacted in the posterior N200. We argue that these results provide electrophysiological evidence that inhibiting and shifting of task set occur before updating in phrase planning.

Abstract

The present study examined how the updating, inhibiting, and shifting abilities underlying executive control influence spoken noun-phrase production. Previous studies provided evidence that updating and inhibiting, but not shifting, influence picture-naming response time (RT). However, little is known about the role of executive control in more complex forms of language production like generating phrases. We assessed noun-phrase production using picture description and a picture–word interference procedure. We measured picture description RT to assess length, distractor, and switch effects, which were assumed to reflect, respectively, the updating, inhibiting, and shifting abilities of adult participants. Moreover, for each participant we obtained scores on executive control tasks that measured verbal and nonverbal updating, nonverbal inhibiting, and nonverbal shifting. We found that both verbal and nonverbal updating scores correlated with the overall mean picture description RTs. Furthermore, the length effect in the RTs correlated with verbal but not nonverbal updating scores, while the distractor effect correlated with inhibiting scores. We did not find a correlation between the switch effect in the mean RTs and the shifting scores. However, the shifting scores correlated with the switch effect in the normal part of the underlying RT distribution. These results suggest that updating, inhibiting, and shifting each influence the speed of phrase production, thereby demonstrating a contribution of all three executive control abilities to language production.

Abstract

During oral reading, the eyes tend to be ahead of the voice (eye-voice span, EVS). It has been hypothesized that the extent to which this happens depends on the automaticity of reading processes, namely on the speed of print-to-sound conversion. We tested whether EVS is affected by another automaticity component – immunity from interference. To that end, we manipulated word familiarity (high-frequency, lowfrequency, and pseudowords, PW) and word length as proxies of immunity from interference, and we used linear mixed effects models to measure the effects of both variables on the time interval at which readers do parallel processing by gazing at word N C 1 while not having articulated word N yet (offset EVS). Parallel processing was enhanced by automaticity, as shown by familiarity length interactions on offset EVS, and it was impeded by lack of automaticity, as shown by the transformation of offset EVS into voice-eye span (voice ahead of the offset of the eyes) in PWs. The relation between parallel processing and automaticity was strengthened by the fact that offset EVS predicted reading velocity. Our findings contribute to understand how the offset EVS, an index that is obtained in oral reading, may tap into different components of automaticity that underlie reading ability, oral or silent. In addition, we compared the duration of the offset EVS with the average reference duration of stages in word production, and we saw that the offset EVS may accommodate for more than the articulatory programming stage of word N.

Abstract

Two different forms of parafoveal dysfunction have been hypothesized as core deficits of dyslexic individuals: reduced parafoveal preview benefits (“too little parafovea”) and increased costs of parafoveal load (“too much parafovea”). We tested both hypotheses in a single eye-tracking experiment using a modified serial rapid automatized naming (RAN) task. Comparisons between dyslexic and non-dyslexic adults showed reduced parafoveal preview benefits in dyslexics, without increased costs of parafoveal load. Reduced parafoveal preview benefits were observed in a naming task, but not in a silent letter-finding task, indicating that the parafoveal dysfunction may be consequent to the overload with extracting phonological information from orthographic input. Our results suggest that dyslexics’ parafoveal dysfunction is not based on strict visuo-attentional factors, but nevertheless they stress the importance of extra-phonological processing. Furthermore, evidence of reduced parafoveal preview benefits in dyslexia may help understand why serial RAN is an important reading predictor in adulthood

Abstract

The spinocerebellar ataxias (SCAs) form an ever-growing group of neurodegenerative disorders causing dysfunction of the cerebellum and loss of motor control in patients. Currently, 41 different genetic causes have been identified, with each mutation affecting a different gene. Interestingly, these diverse genetic causes all disrupt cerebellar function and produce similar symptoms in patients. In order to understand the disease better, and define possible therapeutic targets for multiple SCAs, the field has been searching for common ground among the SCAs. In this review, we discuss the physiology of climbing fibers and the possibility that climbing fiber dysfunction is a point of convergence for at least a subset of SCAs.

Abstract

Spinocerebellar ataxia type 23 (SCA23) is caused by missense mutations in prodynorphin, encoding the precursor protein for the opioid neuropeptides a -neoendorphin, Dynorphin (Dyn) A and Dyn B, leading to neurotoxic elevated mutant Dyn A levels. Dyn A acts on opioid receptors to reduce pain in the spinal cord, but its cerebellar function remains largely unknown. Increased concentration of or prolonged exposure to Dyn A is neurotoxic and these deleterious effects are very likely caused by an N - methyl- D -aspartate-mediated non-opioid mechanism as Dyn A peptides were shown to bind NMDA receptors and potentiate their glutamate-evoked currents. In the present study, we investigated the cellular mechanisms underlying SCA23-mutant Dyn A neurotoxicity. We show that SCA23 mutations in the Dyn A-coding region disrupted peptide secondary structure leading to a loss of the N-terminal a -helix associated with decreased j -opioid receptor affinity. Additionally, the altered secondary structure led to increased peptide stability of R6W and R9C Dyn A, as these peptides showed marked degradation resistance, which coin- cided with decreased peptide solubility. Notably, L5S Dyn A displayed increased degradation and no aggregation. R6W and wt Dyn A peptides were most toxic to primary cerebellar neurons. For R6W Dyn A, this is likely because of a switch from opioid to NMDA- receptor signalling, while for wt Dyn A, this switch was not observed. We propose that the pathology of SCA23 results from converging mechanisms of loss of opioid-mediated neuroprotection and NMDA-mediated excitotoxicity.

Abstract

The present experiment tested the suggestion that human listeners may exploit durational information in speech to parse continuous utterances into words. Listeners were presented with six-syllable unpredictable utterances under noise-masking, and were required to judge between alternative word strings as to which best matched the rhythm of the masked utterances. For each utterance there were four alternative strings: (a) an exact rhythmic and word boundary match, (b) a rhythmic mismatch, and (c) two utterances with the same rhythm as the masked utterance, but different word boundary locations. Listeners were clearly able to perceive the rhythm of the masked utterances: The rhythmic mismatch was chosen significantly less often than any other alternative. Within the three rhythmically matched alternatives, the exact match was chosen significantly more often than either word boundary mismatch. Thus, listeners both perceived speech rhythm and used durational cues effectively to locate the position of word boundaries.