Publications

Abstract

The relationship between print exposure and measures of reading skill was examined in college students (N=99, 58 female; mean age=20.3 years). Print exposure was measured with several new self-reports of reading and writing habits, as well as updated versions of the Author Recognition Test and the Magazine Recognition Test (Stanovich & West, 1989). Participants completed a sentence comprehension task with syntactically complex sentences, and reading times and comprehension accuracy were measured. An additional measure of reading skill was provided by participants’ scores on the verbal portions of the ACT, a standardized achievement test. Higher levels of print exposure were associated with higher sentence processing abilities and superior verbal ACT performance. The relative merits of different print exposure assessments are discussed.

Abstract

Although phonological representations have been a primary focus of verbal working memory research, lexical-semantic manipulations also influence performance. In the present study, the authors investigated whether a classic phenomenon in verbal working memory, the phonological similarity effect (PSE), is modulated by a lexical-semantic variable, word concreteness. Phonological overlap and concreteness were factorially manipulated in each of four experiments across which presentation modality (Experiments 1 and 2: visual presentation; Experiments 3 and 4: auditory presentation) and concurrent articulation (present in Experiments 2 and 4) were manipulated. In addition to main effects of each variable, results show a Phonological Overlap x Concreteness interaction whereby the magnitude of the PSE is greater for concrete word lists relative to abstract word lists. This effect is driven by superior item memory for nonoverlapping, concrete lists and is robust to the modality of presentation and concurrent articulation. These results demonstrate that in verbal working memory tasks, there are multiple routes to the phonological form of a word and that maintenance and retrieval occur over more than just a phonological level.

Abstract

Many accounts of working memory posit specialized storage mechanisms for the maintenance of serial order. We explore an alternative, that maintenance is achieved through temporary activation in the language production architecture. Four experiments examined the extent to which the phonological similarity effect can be explained as a sublexical speech error. Phonologically similar nonword stimuli were ordered to create tongue twister or control materials used in four tasks: reading aloud, immediate spoken recall, immediate typed recall, and serial recognition. Dependent measures from working memory (recall accuracy) and language production (speech errors) fields were used. Even though lists were identical except for item order, robust effects of tongue twisters were observed. Speech error analyses showed that errors were better described as phoneme rather than item ordering errors. The distribution of speech errors was comparable across all experiments and exhibited syllable-position effects, suggesting an important role for production processes. Implications for working memory and language production are discussed.

Abstract

Verbal working memory (WM) tasks typically involve the language production architecture for recall; however, language production processes have had a minimal role in theorizing about WM. A framework for understanding verbal WM results is presented here. In this framework, domain-specific mechanisms for serial ordering in verbal WM are provided by the language production architecture, in which positional, lexical, and phonological similarity constraints are highly similar to those identified in the WM literature. These behavioral similarities are paralleled in computational modeling of serial ordering in both fields. The role of long-term learning in serial ordering performance is emphasized, in contrast to some models of verbal WM. Classic WM findings are discussed in terms of the language production architecture. The integration of principles from both fields illuminates the maintenance and ordering mechanisms for verbal information.

Abstract

This study aimed first to determine whether there is a delay associated with processing words in an unfamiliar regional accent compared to words in a familiar regional accent, and second to establish whether short-term exposure to an unfamiliar accent affects the speed and accuracy of comprehension of words spoken in that accent. Listeners performed an animacy decision task for words spoken in their own and in an unfamiliar accent. Next, they were exposed to approximately 20 minutes of speech in one of these two accents. After exposure, they repeated the animacy decision task. Results showed a considerable delay in word processing for the unfamiliar accent, but no effect of short-term exposure.

Abstract

The authors investigated perceptual learning of a novel accent in young and older listeners through
measuring speech reception thresholds (SRTs) using speech materials spoken in a novel—unfamiliar—
accent. Younger and older listeners adapted to this accent, but older listeners showed poorer comprehension
of the accent. Furthermore, perceptual learning differed across groups: The older listeners
stopped learning after the first block, whereas younger listeners showed further improvement with longer
exposure. Among the older participants, hearing acuity predicted the SRT as well as the effect of the
novel accent on SRT. Finally, a measure of executive function predicted the impact of accent on SRT.

Abstract

Humans imitate each other during social interaction. This imitative behavior streamlines social interaction and aids in learning to replicate actions. However, the effect of imitation on action comprehension is unclear. This study investigated whether vocal imitation of an unfamiliar accent improved spoken-language comprehension. Following a pretraining accent comprehension test, participants were assigned to one of six groups. The baseline group received no training, but participants in the other five groups listened to accented sentences, listened to and repeated accented sentences in their own accent, listened to and transcribed accented sentences, listened to and imitated accented sentences, or listened to and imitated accented sentences without being able to hear their own vocalizations. Posttraining measures showed that accent comprehension was most improved for participants who imitated the speaker’s accent. These results show that imitation may aid in streamlining interaction by improving spoken-language comprehension under adverse listening conditions.

Abstract

Speakers vary their speech rate considerably during a conversation, and listeners are able to quickly adapt to these variations in speech rate. Adaptation to fast speech rates is usually measured using artificially time-compressed speech. This study examined adaptation to two types of fast speech: artificially time-compressed speech and natural fast speech. Listeners performed a speeded sentence verification task on three series of sentences: normal-speed sentences, time-compressed sentences, and natural fast sentences. Listeners were divided into two groups to evaluate the possibility of transfer of learning between the time-compressed and natural fast conditions. The first group verified the natural fast before the time-compressed sentences, while the second verified the time-compressed before the natural fast sentences. The results showed transfer of learning when the time-compressed sentences preceded the natural fast sentences, but not when natural fast sentences preceded the time-compressed sentences. The results are discussed in the framework of theories on perceptual learning. Second, listeners show adaptation to the natural fast sentences, but performance for this type of fast speech does not improve to the level of time-compressed sentences.

Abstract

The development of emotions in the offspring of any species, especially humans, is one of the most important and complex processes necessary to ensure their survival. Although other nonverbal expressions of emotion such as body movements provide valuable clues, facial expressions in human infants are arguably the most crucial component in tracking emotional responses. Tracing the developmental path of facial expressions is thus the aim of this longitudinal research study which explores mother-child interactions from infancy to pre-school in Indian culture via video-taped datasets recorded as part of multiple projects spanning Indian universities (IITD, JNU, DU), Osnabruck University and MPI-Netherlands.

Abstract

Bilinguals are remarkable at language control—switching between languages only when they want. However, language control in production can involve switch costs. That is, switching to another language takes longer than staying in the same language. Moreover, bilinguals sometimes produce language intrusion errors, mistakenly producing words in an unintended language (e.g., Spanish–English bilinguals saying “pero” instead of “but”). Switch costs are also found in comprehension. For example, reading times are longer when bilinguals read sentences with language switches compared to sentences with no language switches. Given that both production and comprehension involve switch costs, some language–control mechanisms might be shared across modalities. To test this, we compared language switch costs found in eye–movement measures during silent sentence reading (comprehension) and intrusion errors produced when reading aloud switched words in mixed–language paragraphs (production). Bilinguals who made more intrusion errors during the read–aloud task did not show different switch cost patterns in most measures in the silent–reading task, except on skipping rates. We suggest that language switching is mostly controlled by separate, modality–specific processes in production and comprehension, although some points of overlap might indicate the role of domain general control and how it can influence individual differences in bilingual language control.

Abstract

Continuous vector word representations (or
word embeddings) have shown success in cap-turing semantic relations between words, as evidenced by evaluation against behavioral data of adult performance on semantic tasks (Pereira et al., 2016). Adult semantic knowl-edge is the endpoint of a language acquisition process; thus, a relevant question is whether these models can also capture emerging word
representations of young language learners. However, the data for children’s semantic knowledge across development is scarce. In this paper, we propose to bridge this gap by using Age of Acquisition norms to evaluate word embeddings learnt from child-directed input. We present two methods that evaluate word embeddings in terms of (a) the semantic neighbourhood density of learnt words, and (b) con-
vergence to adult word associations. We apply our methods to bag-of-words models, and find that (1) children acquire words with fewer semantic neighbours earlier, and (2) young learners only attend to very local context. These findings provide converging evidence for validity of our methods in understanding the prerequisite features for a distributional model of word learning.

Abstract

The present paper assesses discourse-pragmatic factors as a potential explanation for the subject-object assymetry in early child language. It identifies a set of factors which characterize typical situations of informativeness (Greenfield & Smith, 1976), and uses these factors to identify informative arguments in data from four children aged 2;0 through 3;6 learning Inuktitut as a first language. In addition, it assesses the extent of the links between features of informativeness on one hand and lexical vs. null and subject vs. object arguments on the other. Results suggest that a pragmatics account of the subject-object asymmetry can be upheld to a greater extent than previous research indicates, and that several of the factors characterizing informativeness are good indicators of those arguments which tend to be omitted in early child language.

Abstract

Different languages map semantic elements of spatial relations onto different lexical and syntactic units. These crosslinguistic differences raise important questions for language development in terms of how this variation is learned by children. We investigated how Turkish-, English-, and Japanese-speaking children (mean age 3;8) package the semantic elements of Manner and Path onto syntactic units when both the Manner and the Path of the moving Figure occur simultaneously and are salient in the event depicted. Both universal and language-specific patterns were evident in our data. Children used the semantic-syntactic mappings preferred by adult speakers of their own languages, and even expressed subtle syntactic differences that encode different relations between Manner and Path in the same way as their adult counterparts (i.e., Manner causing vs. incidental to Path). However, not all types of semantics-syntax mappings were easy for children to learn (e.g., expressing Manner and Path elements in two verbal clauses). In such cases, Turkish- and Japanese-speaking children frequently used syntactic patterns that were not typical in the target language but were similar to patterns used by English-speaking children, suggesting some universal influence. Thus, both language-specific and universal tendencies guide the development of complex spatial expressions.

Abstract

Previous studies have shown that children retreat from argument-structure overgeneralization errors (e.g., *Don’t giggle me) by inferring that frequently encountered verbs are unlikely to be grammatical in unattested constructions, and by making use of syntax-semantics correspondences (e.g., verbs denoting internally caused actions such as giggling cannot normally be used causatively). The present study tested a new account based on a unitary learning mechanism that combines both of these processes. Seventy-two participants (ages 5–6, 9–10, and adults) rated overgeneralization errors with higher (*The funny man’s joke giggled Bart) and lower (*The funny man giggled Bart) degrees of direct external causation. The errors with more-direct causation were rated as less unacceptable than those with less-direct causation. This finding is consistent with the new account, under which children acquire—in an incremental and probabilistic fashion—the meaning of particular constructions (e.g., transitive causative = direct external causation) and particular verbs, rejecting generalizations where the incompatibility between the two is too great.

Abstract

According to Crain and Nakayama (1987), when forming complex yes/no questions, children do not make errors such as Is the boy who smoking is crazy? because they have innate knowledge of structure dependence and so will not move the auxiliary from the relative clause. However, simple recurrent networks are also able to avoid such errors, on the basis of surface distributional properties of the input (Lewis & Elman, 2001; Reali & Christiansen, 2005). Two new elicited production studies revealed that (a) children occasionally produce structure-dependence errors and (b) the pattern of children's auxiliary-doubling errors (Is the boy who is smoking is crazy?) suggests a sensitivity to surface co-occurrence patterns in the input. This article concludes that current data do not provide any support for the claim that structure dependence is an innate constraint, and that it is possible that children form a structure-dependent grammar on the basis of exposure to input that exhibits this property.

Abstract

A central question in language acquisition is how children master sentence types that they have seldom, if ever, heard. Here we report the findings of a pre-registered, randomised, single-blind intervention study designed to test the prediction that, for one such sentence type, complex questions (e.g., Is the crocodile who’s hot eating?), children could combine schemas learned, on the basis of the input, for complex noun phrases (the [THING] who’s [PROPERTY]) and simple questions (Is [THING] [ACTION]ing?) to yield a complex-question schema (Is [the [THING] who’s [PROPERTY]] ACTIONing?). Children aged 4;2 to 6;8 (M = 5;6, SD = 7.7 months) were trained on simple questions (e.g., Is the bird cleaning?) and either (Experimental group, N = 61) complex noun phrases (e.g., the bird who’s sad) or (Control group, N = 61) matched simple noun phrases (e.g., the sad bird). In general, the two groups did not differ on their ability to produce novel complex questions at test. However, the Experimental group did show (a) some evidence of generalising a particular complex NP schema (the [THING] who’s [PROPERTY] as opposed to the [THING] that’s [PROPERTY]) from training to test, (b) a lower rate of auxiliary-doubling errors (e.g., *Is the crocodile who’s hot is eating?), and (c) a greater ability to produce complex questions on the first test trial. We end by suggesting some different methods – specifically artificial language learning and syntactic priming – that could potentially be used to better test the present account.

Abstract

Participants (aged 5–6 yrs, 9–10 yrs and adults) rated (using a five-point scale) grammatical (intransitive) and overgeneralized (transitive causative)1 uses of a high frequency, low frequency and novel intransitive verb from each of three semantic classes [Pinker, S. (1989a). Learnability and cognition: the acquisition of argument structure. Cambridge, MA: MIT Press]: “directed motion” (fall, tumble), “going out of existence” (disappear, vanish) and “semivoluntary expression of emotion” (laugh, giggle). In support of Pinker’s semantic verb class hypothesis, participants’ preference for grammatical over overgeneralized uses of novel (and English) verbs increased between 5–6 yrs and 9–10 yrs, and was greatest for the latter class, which is associated with the lowest degree of direct external causation (the prototypical meaning of the transitive causative construction). In support of Braine and Brooks’s [Braine, M.D.S., & Brooks, P.J. (1995). Verb argument strucure and the problem of avoiding an overgeneral grammar. In M. Tomasello & W. E. Merriman (Eds.), Beyond names for things: Young children’s acquisition of verbs (pp. 352–376). Hillsdale, NJ: Erlbaum] entrenchment hypothesis, all participants showed the greatest preference for grammatical over ungrammatical uses of high frequency verbs, with this preference smaller for low frequency verbs, and smaller again for novel verbs. We conclude that both the formation of semantic verb classes and entrenchment play a role in children’s retreat from argument-structure overgeneralization errors.

Abstract

Positive and negative what, why and yes/no questions with the 3sg auxiliaries can and does were elicited from 50 children aged 3;3–4;3. In support of the constructivist “schema-combination” account, only children who produced a particular positive question type correctly (e.g., What does she want?) produced a characteristic “auxiliary-doubling” error (e.g., *What does she doesn't want?) for the corresponding negative question type. This suggests that these errors are formed by superimposing a positive question frame (e.g., What does THING PROCESS?) and an inappropriate negative frame (e.g., She doesn't PROCESS) learned from declarative utterances. In addition, a significant correlation between input frequency and correct production was observed for 11 of the 12 lexical frames (e.g., What does THING PROCESS?), although some negative question types showed higher rates of error than one might expect based on input frequency alone. Implications for constructivist and generativist theories of question-acquisition are discussed.

Abstract

This article examines the grammar, use and meaning of fifteen verbs used in the Basic Locative Construction (BLC) of Likpe — a Ghana-Togo-Mountain language. The verbs fall into four semantic subclasses: (a) basic topological relations: t 'be.at', tk 'be.on', kpé 'be.in', and fi 'be.near'; (b) postural verbs: sí 'sit', ny 'stand', fáka 'hang', yóma 'hang', kps 'lean', fus 'squat', and labe 'lie'; (c) “distribution” verbs: kpó 'be spread, heaped,' and tí 'be covered'; and (d) “adhesion” verbs: má 'be griped, be fixed', mánkla 'be stuck to'. Likpe locative predications reflect an ontological commitment to the overall topological relation between Figure and Ground and are not focused just on the Figure or the Ground. Various factors determine the choice of “competing” verbs for particular scenarios: animacy, nonindividuation of the Figure, permanency of the configuration and the speaker's desire to be referentially precise or to present stereotypical information. It is demonstrated that in situations where there is a choice, speakers tend to use the more general verbs (stereotype information). The implications of this tendency for the development of a language from a multiverb language using several verbs (e.g., 15) in its BLC to using only a small-set of verbs in its BLC, just as some of Likpe's neighbors have done, are considered.

Abstract

This special issue is devoted to a relatively neglected topic in linguistics, namely the verbal component of locative statements. English tends, of course, to use a simple copula in utterances like “The cup is on the table”, but many languages, perhaps as many as half of the world's languages, have a set of alternate verbs, or alternate verbal affixes, which contrast in this slot. Often these are classificatory verbs of ‘sitting’, ‘standing’ and ‘lying’. For this reason, perhaps, Aristotle listed position among his basic (“noncomposite”) categories.

Abstract

This book explores the thesis that in the Kwa languages of West Africa, aspect and modality are more central to the grammar of the verb than tense. Where tense marking has emerged it is invariably in the expression of the future, and therefore concerned with the impending actualization or potentiality of an event, hence with modality, rather than the purely temporal sequencing associated with tense. The primary grammatical contrasts are perfective versus imperfective. The main languages discussed are Akan, Dangme, Ewe, Ga and Tuwuli while Nzema-Ahanta, Likpe and Eastern Gbe are also mentioned. Knowledge about these languages has deepened considerably during the past decade or so and ideas about their structure have changed. The volume therefore presents novel analyses of grammatical forms like the so-called S-Aux-O-V-Other or “future” constructions, and provides empirical data for theorizing about aspect and modality. It should be of considerable interest to Africanist linguists, typologists, and creolists interested in substrate issues.

Abstract

Ewe verbs covering the cutting and breaking domain divide into four morpho-syntactic classes that can be ranked according to agentivity. We demonstrate that the highly non-agentive break verbs participate in the causative-inchoative alternation while the highly agentive cut verbs do not, as expected from Guerssel et al.'s (1985) hypothesis. However, four verbs tso 'cut with precision', 'cut', 'snap-off', and dze 'split', are used transitively when an instrument is required for the severance to be effected, and intransitively when not. We reject a lexicalist analysis that would postulate polysemy for these verbs and argue for a construction approach.

Abstract

This paper examines some of the claims of the Unaccusativity hypothesis.It shows that the supposedly unaccusative ‘die’ verb in Ewe (Kwa), kú can appear as both a one-place and a two-place predicate and has three senses which do not correlate with the number of surface arguments of the verb. For instance, the same sense is involved in both a one-place construction (e.g. she died) and a two-place cognate object construction (she died a wicked death). By contrast, different senses are expressed by formally identical two-place constructions, e.g. ‘the garment die dirt’ (= the garment is dead dirty; intensity) vs., ‘he died ear (to the matter)’ (=he does not want to hear; negative desiderative). The paper explores the learnability problems posed by the non-predictability of the different senses of Ewe ‘die’ from its syntactic frame and suggests that since the meanings are indirectly related to the properties of the event participants, such as animacy, a learner must pay close attention to the properties of the verb’s participants. The paper concludes by demonstrating that the meaning shifts observed in Ewe are also attested in other typologically and genetically unrelated languages such as Japanese, Arrernte (Australian), Oluta (Mixean), Dutch and English.

Abstract

This special issue is devoted to a relatively neglected topic in linguistics, namely the verbal component of locative statements. English tends, of course, to use a simple copula in utterances like “The cup is on the table”, but many languages, perhaps as many as half of the world's languages, have a set of alternate verbs, or alternate verbal affixes, which contrast in this slot. Often these are classificatory verbs of 'sitting', 'standing' and 'lying'. For this reason, perhaps, Aristotle listed position among his basic (“noncomposite”) categories.

Abstract

Kwa languages such as Akye, Akan, Ewe, Ga, Likpe, Yoruba etc. are not prototypically “topic-prominent” like Chinese nor “focus-prominent” like Somali, yet they have dedicated structural positions in the clause, as well as morphological markers for signalling the information status of the component parts of information units. They could thus be seen as “discourse configurational languages” (Kiss 1995). In this chapter, I first argue for distinct positions in the left periphery of the clause in these languages for scene-setting topics, contrastive topics and focus. I then describe the morpho-syntactic properties of various information packaging constructions and the variations that we find across the languages in this domain.

Abstract

Particles are little words that speakers use to signal the illocutionary force of utterances and/or express their attitude towards elements of the communicative situation, e.g. the addresses. This paper presents an overview of the classification, meaning and use of utterance particles in Ewe. It argues that they constitute a grammatical word class on functional and distributional grounds. The paper calls for a cross-cultural investigation of particles, especially in Africa, where they have been neglected for far too long.

Abstract

This paper briefly presents the current situation of bilingualism in the Philippines,
specifically that of Tagalog-English bilingualism. More importantly, it describes the process of adapting the Multilingual Assessment Instrument for Narratives (LITMUS-MAIN) to Tagalog, the basis of Filipino, which is the country’s national language.
Finally, the results of a pilot study conducted on Tagalog-English bilingual children and
adults (N=27) are presented. The results showed that Story Structure is similar across the
two languages and that it develops significantly with age.

Abstract

We present results from an experiment which shows that voice perception is influenced by the phonetic content of speech. Dutch listeners were presented with thirteen speakers pronouncing CVC words with systematically varying segmental content, and they had to discriminate the speakers’ voices. Results show that certain segments help listeners discriminate voices more than other segments do. Voice information can be extracted from every segmental position of a monosyllabic word and is processed rapidly. We also show that although relative discriminability within a closed set of voices appears to be a stable property of a voice, it is also influenced by segmental cues – that is, perceived uniqueness of a voice depends on what that voice says.

Abstract

We investigated neural mechanisms that support voice recognition in a training paradigm with fMRI. The same listeners were trained on different weeks to categorize the mid-regions of voice-morph continua as an individual's voice. Stimuli implicitly defined a voice-acoustics space, and training explicitly defined a voice-identity space. The predefined centre of the voice category was shifted from the acoustic centre each week in opposite directions, so the same stimuli had different training histories on different tests. Cortical sensitivity to voice similarity appeared over different time-scales and at different representational stages. First, there were short-term adaptation effects: Increasing acoustic similarity to the directly preceding stimulus led to haemodynamic response reduction in the middle/posterior STS and in right ventrolateral prefrontal regions. Second, there were longer-term effects: Response reduction was found in the orbital/insular cortex for stimuli that were most versus least similar to the acoustic mean of all preceding stimuli, and, in the anterior temporal pole, the deep posterior STS and the amygdala, for stimuli that were most versus least similar to the trained voice-identity category mean. These findings are interpreted as effects of neural sharpening of long-term stored typical acoustic and category-internal values. The analyses also reveal anatomically separable voice representations: one in a voice-acoustics space and one in a voice-identity space. Voice-identity representations flexibly followed the trained identity shift, and listeners with a greater identity effect were more accurate at recognizing familiar voices. Voice recognition is thus supported by neural voice spaces that are organized around flexible ‘mean voice’ representations.

Abstract

There are some historical divisions in methods, rationales, and purposes between
studies on comparative cognition and behavioural ecology. In turn, the interaction between
these two branches and studies from mathematics, computation and neuroscience is not
usual. In this short piece, we attempt to build bridges among these disciplines. We present a
series of interconnected vignettes meant to illustrate how a more interdisciplinary approach
looks like when successful, and its advantages. Concretely, we focus on a recent topic,
namely animal rhythms in interaction, studied under different approaches. We showcase 5
research efforts, which we believe successfully link 5 particular Scientific areas of rhythm
research conceptualized as: Social neuroscience, Detailed rhythmic quantification,
Ontogeny, Computational approaches and Spontaneous interactions. Our suggestions will
hopefully spur a ‘Comparative rhythms in interaction’ field, which can integrate and
capitalize on knowledge from zoology, comparative psychology, neuroscience, and
computation.

Abstract

The meaning of a sentence can be understood, whether presented in written or spoken form. Therefore it is highly probable that brain processes supporting language comprehension are at least partly independent of sensory modality. To identify where and when in the brain language processing is independent of sensory modality, we directly compared neuromagnetic brain signals of 200 human subjects (102 males) either reading or listening to sentences. We used multiset canonical correlation analysis to align individual subject data in a way that boosts those aspects of the signal that are common to all, allowing us to capture word-by-word signal variations, consistent across subjects and at a fine temporal scale. Quantifying this consistency in activation across both reading and listening tasks revealed a mostly left hemispheric cortical network. Areas showing consistent activity patterns include not only areas previously implicated in higher-level language processing, such as left prefrontal, superior & middle temporal areas and anterior temporal lobe, but also parts of the control-network as well as subcentral and more posterior temporal-parietal areas. Activity in this supramodal sentence processing network starts in temporal areas and rapidly spreads to the other regions involved. The findings do not only indicate the involvement of a large network of brain areas in supramodal language processing, but also indicate that the linguistic information contained in the unfolding sentences modulates brain activity in a word-specific manner across subjects.

Abstract

One implication of the double-deficit hypothesis for dyslexia is that there should be subtypes of dyslexic readers that exhibit rapid naming deficits with or without concomitant phonological processing problems. In the current study, we investigated the validity of this hypothesis for Portuguese orthography, which is more consistent than English orthography, by exploring different cognitive profiles in a sample of dyslexic children. In particular, we were interested in identifying readers characterized by a pure rapid automatized naming deficit. We also examined whether rapid naming and phonological awareness independently account for individual differences in reading performance. We characterized the performance of dyslexic readers and a control group of normal readers matched for age on reading, visual rapid naming and phonological processing tasks. Our results suggest that there is a subgroup of dyslexic readers with intact phonological processing capacity (in terms of both accuracy and speed measures) but poor rapid naming skills. We also provide evidence for an independent association between rapid naming and reading competence in the dyslexic sample, when the effect of phonological skills was controlled. Altogether, the results are more consistent with the view that rapid naming problems in dyslexia represent a second core deficit rather than an exclusive phonological explanation for the rapid naming deficits. Furthermore, additional non-phonological processes, which subserve rapid naming performance, contribute independently to reading development.

Abstract

Native-speaker listeners constantly predict upcoming units of speech as part of language processing, using various cues.
However, this process is impeded in second-language listeners, as well as when the speaker has an unfamiliar accent.
Whereas previous research has largely concentrated on the pronunciation of individual segments in foreign-accented speech,
we show that regional accent impedes higher levels of language processing, making native listeners’ processing resemble that of
second-language listeners.
In Experiment 1, 42 native speakers of Canadian English followed instructions spoken in British English to move objects on a
screen while their eye movements were tracked. Native listeners use prosodic cues to information status to disambiguate between
two possible referents, a new and a previously mentioned one, before they have heard the complete word. By contrast, the
Canadian participants, similarly to second-language speakers, were not able to make full use of prosodic cues in the way native
British listeners do.
In Experiment 2, 19 native speakers of Canadian English rated the British English instructions used in Experiment 1, as well as
the same instructions spoken by a Canadian imitating the British English prosody. While information status had no effect for the
Canadian imitations, the original stimuli received higher ratings when prosodic realization and information status of the referent
matched than for mismatches, suggesting a native-like competence in these offline ratings.
These findings underline the importance of expanding psycholinguistic models of second language/dialect processing and
representation to include both prosody and regional variation.

Abstract

A production experiment investigated the tonal shape of Finnish finite verbs in transitive sentences without narrow focus. Traditional descriptions of Finnish stating that non-focused finite verbs do not receive accents were only partly supported. Verbs were found to have a consistently smaller pitch range than words in other word classes, but their pitch contours were neither flat nor explainable by pure interpolation.

Abstract

Across diverse lineages, animals communicate using chemosignals, but only humans communicate about chemical signals. Many studies have observed that compared with other sensory modalities, communication about smells is relatively rare and not always reliable. Recent cross-cultural studies, on the other hand, suggest some communities are more olfactorily oriented than previously supposed. Nevertheless, across the globe a general trend emerges where olfactory communication is relatively hard. We suggest here that this is in part because olfactory representations are different in kind: they have a low degree of embodiment, and are not easily expressed as primitives, thereby limiting the mental manipulations that can be performed with them. New exploratory data from Dutch children (9–12 year-olds) and adults support that mental imagery from olfaction is weak in comparison with vision and audition, and critically this is not affected by language development. Specifically, while visual and auditory imagery becomes more vivid with age, olfactory imagery shows no such development. This is consistent with the idea that olfactory representations are different in kind from representations from the other senses.

Abstract

The term “uptalk” describes utterance-final pitch rises that carry no sentence-structural information. Uptalk is usually dialectal or sociolectal, and Australian English (AusEng) is particularly known for this attribute. We ask here whether experience with an uptalk variety affects listeners’ ability to categorise rising pitch contours on the basis of the timing and height of their onset and offset. Listeners were two groups of English-speakers (AusEng, and American English), and three groups of listeners with L2 English: one group with Mandarin as L1 and experience of listening to AusEng, one with German as L1 and experience of listening to AusEng, and one with German as L1 but no AusEng experience. They heard nouns (e.g. flower, piano) in the framework “Got a NOUN”, each ending with a pitch rise artificially manipulated on three contrasts: low vs. high rise onset, low vs. high rise offset and early vs. late rise onset. Their task was to categorise the tokens as “question” or “statement”, and we analysed the effect of the pitch contrasts on their judgements. Only the native AusEng listeners were able to use the pitch contrasts systematically in making these categorisations.

Abstract

Two experiments examined the nature of the phonological representations used during visual word recognition. We tested whether a minimality constraint (R. Frost, 1998) limits the complexity of early representations to a simple string of phonemes. Alternatively, readers might activate elaborated representations that include prosodic syllable information before lexical access. In a modified lexical decision task (Experiment 1), words were preceded by parafoveal previews that were congruent with a target's initial syllable as well as previews that contained 1 letter more or less than the initial syllable. Lexical decision times were faster in the syllable congruent conditions than in the incongruent conditions. In Experiment 2, we recorded brain electrical potentials (electroencephalograms) during single word reading in a masked priming paradigm. The event-related potential waveform elicited in the syllable congruent condition was more positive 250-350 ms posttarget compared with the waveform elicited in the syllable incongruent condition. In combination, these experiments demonstrate that readers process prosodic syllable information early in visual word recognition in English. They offer further evidence that skilled readers routinely activate elaborated, speechlike phonological representations during silent reading. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Abstract

In the paper we describe a new attempt to come to automatic detectors processing real scene audio-video streams that can be used by researchers world-wide to speed up their annotation and analysis work. Typically these recordings are taken in field and experimental situations mostly with bad quality and only little corpora preventing to use standard stochastic pattern recognition techniques. Audio/video processing components are taken out of the expert lab and are integrated in easy-to-use interactive frameworks so that the researcher can easily start them with modified parameters and can check the usefulness of the created annotations. Finally a variety of detectors may have been used yielding a lattice of annotations. A flexible search engine allows finding combinations of patterns opening completely new analysis and theorization possibilities for the researchers who until were required to do all annotations manually and who did not have any help in pre-segmenting lengthy media recordings.

Abstract

Annotation of digital recordings in humanities research still is, to a largeextend, a process that is performed manually. This paper describes the firstpattern recognition based software components developed in the AVATecH projectand their integration in the annotation tool ELAN. AVATecH (AdvancingVideo/Audio Technology in Humanities Research) is a project that involves twoMax Planck Institutes (Max Planck Institute for Psycholinguistics, Nijmegen,Max Planck Institute for Social Anthropology, Halle) and two FraunhoferInstitutes (Fraunhofer-Institut für Intelligente Analyse- undInformationssysteme IAIS, Sankt Augustin, Fraunhofer Heinrich-Hertz-Institute,Berlin) and that aims to develop and implement audio and video technology forsemi-automatic annotation of heterogeneous media collections as they occur inmultimedia based research. The highly diverse nature of the digital recordingsstored in the archives of both Max Planck Institutes, poses a huge challenge tomost of the existing pattern recognition solutions and is a motivation to makesuch technology available to researchers in the humanities.

Abstract

This paper investigates whether there are changes in gesture rate when speakers of two languages with different gesture rates (Turkish-high gesture; Dutch-low gesture) come into daily contact. We analyzed gestures produced by second-generation heritage speakers of Turkish in the Netherlands in each language, comparing them to monolingual baselines. We did not find differences between bilingual and monolingual speakers, possibly because bilinguals were proficient in both languages and used them frequently – in line with a usage-based approach to language. However, bilinguals produced more deictic gestures than monolinguals in both Turkish and Dutch, which we interpret as a bilingual strategy. Deictic gestures may help organize discourse by placing entities in gesture space and help reduce the cognitive load associated with being bilingual, e.g., inhibition cost. Therefore, gesture rate does not necessarily change in contact situations but might be modulated by frequency of language use, proficiency, and cognitive factors related to being bilingual.

Abstract

Aim:

This paper examines whether second-generation Turkish heritage speakers in the Netherlands follow language-specific patterns of reference tracking in Turkish and Dutch, focusing on discourse status and pragmatic contexts as factors that may modulate the choice of referring expressions (REs), that is, the noun phrase (NP), overt pronoun and null pronoun.
Methodology:

Two short silent videos were used to elicit narratives from 20 heritage speakers of Turkish, both in Turkish and in Dutch. Monolingual baseline data were collected from 20 monolingually raised speakers of Turkish in Turkey and 20 monolingually raised speakers of Dutch in the Netherlands. We also collected language background data from bilinguals with an extensive survey.
Data and analysis:

Using generalised logistic mixed-effect regression, we analysed the influence of discourse status and pragmatic context on the choice of subject REs in Turkish and Dutch, comparing bilingual data to the monolingual baseline in each language.
Findings:

Heritage speakers used overt versus null pronouns in Turkish and stressed versus reduced pronouns in Dutch in pragmatically appropriate contexts. There was, however, a slight increase in the proportions of overt pronouns as opposed to NPs in Turkish and as opposed to null pronouns in Dutch. We suggest an explanation based on the degree of entrenchment of differential RE types in relation to discourse status as the possible source of the increase.
Originality:

This paper provides data from an understudied language pair in the domain of reference tracking in language contact situations. Unlike several studies of pronouns in language contact, we do not find differences across monolingual and bilingual speakers with regard to pragmatic constraints on overt pronouns in the minority pro-drop language.
Significance:

Our findings highlight the importance of taking language proficiency and use into account while studying bilingualism and combining formal approaches to language use with usage-based approaches for a more complete understanding of bilingual language production.

Abstract

The main goal of the present study is to trace the consequences of local and global markedness for the processing of singular and plural nouns. Decompositional models such as proposed by (Pinker (1997); Pinker (1999)) and (Levelt et al. (1999)) predict a lexeme frequency effect and no effects of the frequencies of the singular and the plural forms. Experiments 1 and 4 reveal the expected lexeme frequency effect. Furthermore, in these experiments there are no clear independent effects of the frequencies of the inflected forms. However, the effects of Entropy and Relative Entropy that emerge from these experiments show that in production knowledge of the probabilities of the individual inflected forms do play a role, albeit indirectly. These entropy effects bear witness to the importance of paradigmatic organization of inflected forms in the mental lexicon, both at the level of individual lexemes (Entropy) and at the general level of the class of nouns (Relative Entropy).

Abstract

This paper provides an introduction to mixed-effects models for the analysis of repeated measurement data with subjects and items as crossed random effects. A worked-out example of how to use recent software for mixed-effects modeling is provided. Simulation studies illustrate the advantages offered by mixed-effects analyses compared to traditional analyses based on quasi-F tests, by-subjects analyses, combined by-subjects and by-items analyses, and random regression. Applications and possibilities across a range of domains of inquiry are discussed.

Abstract

Research in psycholinguistics and in the cognitive neuroscience of language has suggested that semantic and syntactic integration are associated with different neurophysiologic correlates, such as the N400 and the P600 in the ERPs. However, only a handful of studies have investigated the neural basis of the syntax–semantics interface, and even fewer experiments have dealt with the cases in which semantic composition can proceed independently of the syntax. Here we looked into one such case—complement coercion—using ERPs. We compared sentences such as, “The journalist wrote the article” with “The journalist began the article.” The second sentence seems to involve a silent semantic element, which is expressed in the first sentence by the head of the VP “wrote the article.” The second type of construction may therefore require the reader to infer or recover from memory a richer event sense of the VP “began the article,” such as began writing the article, and to integrate that into a semantic representation of the sentence. This operation is referred to as “complement coercion.” Consistently with earlier reading time, eye tracking, and MEG studies, we found traces of such additional computations in the ERPs: Coercion gives rise to a long-lasting negative shift, which differs at least in duration from a standard N400 effect. Issues regarding the nature of the computation involved are discussed in the light of a neurocognitive model of language processing and a formal semantic analysis of coercion.

Abstract

While syntactic reanalysis has been extensively investigated in psycholinguistics, comparatively little is known about reanalysis in the semantic domain. We used event-related brain potentials (ERPs) to keep track of semantic processes involved in understanding short narratives such as ‘The girl was writing a letter when her friend spilled coffee on the paper’. We hypothesize that these sentences are interpreted in two steps: (1) when the progressive clause is processed, a discourse model is computed in which the goal state (a complete letter) is predicted to hold; (2) when the subordinate clause is processed, the initial representation is recomputed to the effect that, in the final discourse structure, the goal state is not satisfied. Critical sentences evoked larger sustained anterior negativities (SANs) compared to controls, starting around 400 ms following the onset of the sentence-final word, and lasting for about 400 ms. The amplitude of the SAN was correlated with the frequency with which participants, in an offline probe-selection task, responded that the goal state was not attained. Our results raise the possibility that the brain supports some form of non-monotonic recomputation to integrate information which invalidates previously held assumptions.

Abstract

This study provides evidence for the role of semantic composition in compound word processing. We examined the online processing of isolated two meaning unit compounds in Chinese, a language that uses compounding to ‘disambiguate’ meaning. Using auditory presentation, we manipulated the semantic meaning and syntactic category of the two meaning units forming a compound. Event-related brain potential-recordings revealed a significant influence of semantic information, which was reflected in an N400 signature for compounds whose meaning differed from the constituent meanings. This finding suggests that the combination of distinct constituent meanings to form an overall compound meaning consumes processing resources. By contrast, no comparable difference was observed based on syntactic category information. Our findings indicate that combinatory semantic processing at the word level correlates with N400 effects.

Abstract

Autism is characterized by impairments in reciprocal social interaction and communication, and restricted and sterotyped patterns of interests and activities. Developmental difficulties are apparent before 3 years of age and there is evidence for strong genetic influences most likely involving more than one susceptibility gene. A two-stage genome search for susceptibility loci in autism was performed on 87 affected sib pairs plus 12 non-sib affected relative-pairs, from a total of 99 families identified by an international consortium. Regions on six chromosomes (4, 7, 10, 16, 19 and 22) were identified which generated a multipoint maximum lod score (MLS) > 1. A region on chromosome 7q was the most significant with an MLS of 3.55 near markers D7S530 and D7S684 in the subset of 56 UK affected sib-pair families, and an MLS of 2.53 in all 87 affected sib-pair families. An area on chromosome 16p near the telomere was the next most significant, with an MLS of 1.97 in the UK families, and 1.51 in all families. These results are an important step towards identifying genes predisposing to autism; establishing their general applicability requires further study.

Abstract

Our ability to recognise the emotions of others is a crucial feature of human social cognition. Functional neuroimaging studies indicate that activity in sensorimotor cortices is evoked during the perception of emotion. In the visual domain, right somatosensory cortex activity has been shown to be critical for facial emotion recognition. However, the importance of sensorimotor representations in modalities outside of vision remains unknown. Here we use continuous theta-burst transcranial magnetic stimulation (cTBS) to investigate whether neural activity in the right postcentral gyrus (rPoG) and right lateral premotor cortex (rPM) is involved in non-verbal auditory emotion recognition. Three groups of participants completed same-different tasks on auditory stimuli, discriminating between either the emotion expressed or the speakers' identities, prior to and following cTBS targeted at rPoG, rPM or the vertex (control site). A task-selective deficit in auditory emotion discrimination was observed. Stimulation to rPoG and rPM resulted in a disruption of participants' abilities to discriminate emotion, but not identity, from vocal signals. These findings suggest that sensorimotor activity may be a modality independent mechanism which aids emotion discrimination.

Abstract

Artificial lexicons have previously been used to examine the time course of the learning and recognition of spoken words, the role of segment type in word learning, and the integration of context during spoken word recognition. However, in all of these studies the experimenter determined the frequency and order of the words to be learned. In three experiments, we asked whether adult learners choose to listen to novel words in a particular order based on their acoustic similarity. We use a new paradigm for learning an artificial lexicon in which the learner, rather than the experimenter, determines the order and frequency of exposure to items. We analyze both the proportions of selections and the temporal clustering of subjects' sampling of lexical neighborhoods during training as well as their performance during repeated testing phases (accuracy and reaction time) to determine the time course of learning these neighborhoods. In the first experiment, subjects sampled the high and low density neighborhoods randomly in early learning, and then over-sampled the high density neighborhood until test performance on both neighborhoods reached asymptote. A second experiment involved items similar to the first, but also neighborhoods that are not fully revealed at the start of the experiment. Subjects adjusted their training patterns to focus their selections on neighborhoods of increasing density was revealed; evidence of learning in the test phase was slower to emerge than in the first experiment, impaired by the presence of additional sets of items of varying density. Crucially, in both the first and second experiments there was no effect of dense vs. sparse neighborhood in the accuracy results, which is accounted for by subjects’ over-sampling of items from the dense neighborhood. The third experiment was identical in design to the second except for a second day of further training and testing on the same items. Testing at the beginning of the second day showed impaired, not improved, accuracy, except for the consistently dense items. Further training, however, improved accuracy for some items to above Day 1 levels. Overall, these results provide a new window on the time-course of learning an artificial lexicon and the role that learners’ implicit preferences, stemming from their self-selected experience with the entire lexicon, play in learning highly confusable words.

Abstract

In multilevel data, units at level 1 are nested in clusters at level 2, which in turn may be nested in even larger clusters at level 3, and so on. For continuous data, several authors have shown how to model multilevel data in a ‘wide’ or ‘multivariate’ format approach. We provide a general framework to analyze random intercept multilevel SEM in the ‘wide format’ (WF) and extend this approach for discrete data. In a simulation study, we vary response scale (binary, four response options), covariate presence (no, between-level, within-level), design (balanced, unbalanced), model misspecification (present, not present), and the number of clusters (small, large) to determine accuracy and efficiency of the estimated model parameters. With a small number of observations in a cluster, results indicate that the WF approach is a preferable approach to estimate multilevel data with discrete response options.

Abstract

Factor analysis is an established technique for the detection of measurement bias. Multigroup factor analysis (MGFA) can detect both uniform and nonuniform bias. Restricted factor analysis (RFA) can also be used to detect measurement bias, albeit only uniform measurement bias. Latent moderated structural equations (LMS) enable the estimation of nonlinear interaction effects in structural equation modelling. By extending the RFA method with LMS, the RFA method should be suited to detect nonuniform bias as well as uniform bias. In a simulation study, the RFA/LMS method and the MGFA method are compared in detecting uniform and nonuniform measurement bias under various conditions, varying the size of uniform bias, the size of nonuniform bias, the sample size, and the ability distribution. For each condition, 100 sets of data were generated and analysed through both detection methods. The RFA/LMS and MGFA methods turned out to perform equally well. Percentages of correctly identified items as biased (true positives) generally varied between 92% and 100%, except in small sample size conditions in which the bias was nonuniform and small. For both methods, the percentages of false positives were generally higher than the nominal levels of significance.

Abstract

When listeners hear a speaker become disfluent, they expect the speaker to refer to something new. What is the mechanism underlying this expectation? In a mouse-tracking experiment, listeners sought to identify images that a speaker was describing. Listeners more strongly expected new referents when they heard a speaker say um than when they heard a matched utterance where the um was replaced by noise. This expectation was speaker-specific: it depended on what was new and old for the current speaker, not just on what was new or old for the listener. This finding suggests that listeners treat fillers as collateral signals.

Abstract

The frontal lobe is central to distinctive aspects of human cognition and behavior. Some comparative studies link this to a larger frontal cortex and even larger frontal white matter in humans compared with other primates, yet others dispute these findings. The discrepancies between studies could be explained by limitations of the methods used to quantify volume differences across species, especially when applied to white matter connections. In this study, we used a novel tractography approach to demonstrate that frontal lobe networks, extending within and beyond the frontal lobes, occupy 66% of total brain white matter in humans and 48% in three monkey species: vervets (Chlorocebus aethiops), rhesus macaque (Macaca mulatta) and cynomolgus macaque (Macaca fascicularis), all male. The simian–human differences in proportional frontal tract volume were significant for projection, commissural, and both intralobar and interlobar association tracts. Among the long association tracts, the greatest difference was found for tracts involved in motor planning, auditory memory, top-down control of sensory information, and visuospatial attention, with no significant differences in frontal limbic tracts important for emotional processing and social behaviour. In addition, we found that a nonfrontal tract, the anterior commissure, had a smaller volume fraction in humans, suggesting that the disproportionally large volume of human frontal lobe connections is accompanied by a reduction in the proportion of some nonfrontal connections. These findings support a hypothesis of an overall rearrangement of brain connections during human evolution.

Abstract

To ensure short gaps between turns in conversation, next speakers regularly start planning their utterance in overlap with the incoming turn. Three experiments investigate which stages of utterance planning are executed in overlap. E1 establishes effects of associative and phonological relatedness of pictures and words in a switch-task from picture naming to lexical decision. E2 focuses on effects of phonological relatedness and investigates potential shifts in the time-course of production planning during background speech. E3 required participants to verbally answer questions as a base task. In critical trials, however, participants switched to visual lexical decision just after they began planning their answer. The task-switch was time-locked to participants' gaze for response planning. Results show that word form encoding is done as early as possible and not postponed until the end of the incoming turn. Hence, planning a response during the incoming turn is executed at least until word form activation.

Abstract

An influential hypothesis regarding the neural basis of the mental lexicon is that semantic representations are neurally implemented as distributed networks carrying sensory, motor and/or more abstract functional information. This work investigates whether the semantic properties of words partly determine the topography of such networks. Subjects performed a visual lexical decision task while their EEG was recorded. We compared the EEG responses to nouns with either visual semantic properties (VIS, referring to colors and shapes) or with auditory semantic properties (AUD, referring to sounds). A time–frequency analysis of the EEG revealed power increases in the theta (4–7 Hz) and lower-beta (13–18 Hz) frequency bands, and an early power increase and subsequent decrease for the alpha (8–12 Hz) band. In the theta band we observed a double dissociation: temporal electrodes showed larger theta power increases in the AUD condition, while occipital leads showed larger theta responses in the VIS condition. The results support the notion that semantic representations are stored in functional networks with a topography that reflects the semantic properties of the stored items, and provide further evidence that oscillatory brain dynamics in the theta frequency range are functionally related to the retrieval of lexical semantic information.

Abstract

There is growing evidence suggesting that synchronization changes in the oscillatory neuronal dynamics in the EEG or MEG reflect the transient coupling and uncoupling of functional networks related to different aspects of language comprehension. In this work, we examine how sentence-level syntactic unification operations are reflected in the oscillatory dynamics of the MEG. Participants read sentences that were either correct, contained a word category violation, or were constituted of random word sequences devoid of syntactic structure. A time-frequency analysis of MEG power changes revealed three types of effects. The first type of effect was related to the detection of a (word category) violation in a syntactically structured sentence, and was found in the alpha and gamma frequency bands. A second type of effect was maximally sensitive to the syntactic manipulations: A linear increase in beta power across the sentence was present for correct sentences, was disrupted upon the occurrence of a word category violation, and was absent in syntactically unstructured random word sequences. We therefore relate this effect to syntactic unification operations. Thirdly, we observed a linear increase in theta power across the sentence for all syntactically structured sentences. The effects are tentatively related to the building of a working memory trace of the linguistic input. In conclusion, the data seem to suggest that syntactic unification is reflected by neuronal synchronization in the lower-beta frequency band.

Abstract

This article argues that with the original emphasis on dialectal variation, using primarily literary texts from various regions, analysis of Old French has routinely neglected social variation, providing an incomplete picture of its grammar. Accordingly, Old French has been identified as typically featuring e.g. “pro-drop”, brace constructions, and single negation. Yet examination of these features in informal texts, as opposed to the formal texts typically dealt with, demonstrates that these documents do not corroborate the picture of Old French that is commonly presented in the linguistic literature. Our reconstruction of Old French grammar therefore needs adjustment and further refinement, in particular by implementing sociolinguistic data. With a broader scope, the call for inclusion of sociolinguistic variation may resonate in the investigation of other early languages, resulting in the reassessment of the sources used, and reopening the debate about social variation in dead languages and its role in language evolution.

Abstract

The literature suggests that individuals with autism spectrum disorders (ASD) are deficient in their Theory of Mind (ToM) abilities. They sometimes do not seem to appreciate that behaviour is motivated by underlying mental states. If this is true, then individuals with ASD should also be deficient when they use their ToM to represent and take part in dyadic interactions. In the current study we compared the performance of normally intelligent adolescents and adults with ASD to typically developing controls. In one task they heard a narrative about an interaction and then retold it. In a second task they played a communication game that required them to take into account another person's perspective. We found that when they described people's behaviour the ASD individuals used fewer mental terms in their story narration, suggesting a lower tendency to represent interactions in mentalistic terms. Surprisingly, ASD individuals and control participants showed the same level of performance in the communication game that required them to distinguish between their beliefs and the other's beliefs. Given that ASD individuals show no deficiency in using their ToM in real interaction, it is unlikely that they have a systematically deficient ToM.

Abstract

To form a more reliable percept of the environment, the brain needs to estimate its own sensory uncertainty. Current theories of perceptual inference assume that the brain computes sensory uncertainty instantaneously and independently for each stimulus. We evaluated this assumption in four psychophysical experiments, in which human observers localized auditory signals that were presented synchronously with spatially disparate visual signals. Critically, the visual noise changed dynamically over time continuously or with intermittent jumps. Our results show that observers integrate audiovisual inputs weighted by sensory uncertainty estimates that combine information from past and current signals consistent with an optimal Bayesian learner that can be approximated by exponential discounting. Our results challenge leading models of perceptual inference where sensory uncertainty estimates depend only on the current stimulus. They demonstrate that the brain capitalizes on the temporal dynamics of the external world and estimates sensory uncertainty by combining past experiences with new incoming sensory signals.

Abstract

We compared the performance of young (college-aged) and older (50+years) speakers in a single object and a multiple object naming task and assessed their susceptibility to semantic and phonological context effects when producing words amidst semantically or phonologically similar or dissimilar words. In single object naming, there were no performance differences between the age groups. In multiple object naming, we observed significant age-related slowing, expressed in longer gazes to the objects and slower speech. In addition, the direction of the phonological context effects differed for the two groups. The results of a supplementary experiment showed that young speakers, when adopting a slow speech rate, coordinated their eye movements and speech differently from the older speakers. Our results imply that age-related slowing in connected speech is not a direct consequence of a slowing of lexical retrieval processes. Instead, older speakers might allocate more processing capacity to speech monitoring processes, which would slow down their concurrent speech planning processes