Publications

Abstract

Relational grammar was proposed in Suppes (1976) as a semantical grammar for natural language. Fragments considered so far are restricted to distributive notions. In this article, relational grammar is extended to collective notions.

Abstract

The notion of relational grammar is extented to ternary relations and illustrated by a fragment of English. Some of Peirce's terms for ternary relations are shown to be incorrect and corrected.

Abstract

The acquisition of literacy has a profound impact on the functional specialization and lateralization of the visual cortex. Due to the overall lateralization of the language network, specialization for printed words develops in the left occipitotemporal cortex, allegedly inducing a secondary shift of visual face processing to the right, in literate as compared to illiterate subjects. Applying the same logic to the acquisition of high-level musical literacy, we predicted that, in musicians as compared to non-musicians, occipitotemporal activations should show a leftward shift for music reading, and an additional rightward push for face perception. To test these predictions, professional musicians and non-musicians viewed pictures of musical notation, faces, words, tools and houses in the MRI, and laterality was assessed in the ventral stream combining ROI and voxel-based approaches. The results supported both predictions, and allowed to locate the leftward shift to the inferior temporal gyrus and the rightward shift to the fusiform cortex. Moreover, these laterality shifts generalized to categories other than music and faces. Finally, correlation measures across subjects did not support a causal link between the leftward and rightward shifts. Thus the acquisition of an additional perceptual expertise extensively modifies the laterality pattern in the visual system

Abstract

This paper introduces the EU-FP7 project CLARIN, a joint effort of over 150 institutions in Europe, aimed at the creation of a sustainable language resources and technology infrastructure for the humanities and social sciences research community. The paper briefly introduces the vision behind the project and how it relates to speech research with a focus on the contributions that CLARIN can and will make to research in spoken language processing.

Abstract

Reprinted from; Bowerman, M. (1989). Learning a semantic system: What role do cognitive predispositions play? In M.L. Rice & R.L Schiefelbusch (Ed.), The teachability of language (pp. 133-169). Baltimore: Paul H. Brookes.

Abstract

(From the chapter) the first section considers very briefly the kinds of processes that can be inferred to underlie errors that do not set in until after a period of correct usage acquisition often seems to be a more extended process than we have envisioned summarize a currently influential model of how linguistic forms, meaning, and communication are interrelated in the acquisition of language, point out some challenging problems for this model, and suggest that the notion of "meaning" in language must be reconceptualized before we can hope to solve these problems evidence from several types of late errors is marshalled in support of these arguments (From the preface) provides many examples of new errors that children introduce at relatively advanced stages of mastery of semantics and syntax Bowerman views these seemingly backwards steps as indications of definite steps forward by the child achieving reflective, flexible and integrated systems of semantics and syntax (

Abstract

Kids’ Cut & Break is a task inspired by the original Cut & Break task (see MPI L&C Group Field Manual 2001), but designed for use with children as well as adults. There are fewer videoclips to be described (34 as opposed to 61), and they are “friendlier” and more interesting: the actors wear colorful clothes, smile, and act cheerfully. The first 2 items are warm-ups and 4 more items are fillers (interspersed with test items), so only 28 of the items are actually “test items”. In the original Cut & Break, each clip is in a separate file. In Kids’ Cut & Break, all 34 clips are edited into a single file, which plays the clips successively with 5 seconds of black screen between each clip.

Abstract

This study reports three experiments on how children learning Mandarin Chinese comprehend and use aspect markers. These experiments examine the role of lexical aspect in children's acquisition of grammatical aspect. Results provide converging evidence for children's early sensitivity to (1) the association between atelic verbs and the imperfective aspect markers zai, -zhe, and -ne, and (2) the association between telic verbs and the perfective aspect marker -le. Children did not show a sensitivity in their use or understanding of aspect markers to the difference between stative and activity verbs or between semelfactive and activity verbs. These results are consistent with Slobin's (1985) basic child grammar hypothesis that the contrast between process and result is important in children's early acquisition of temporal morphology. In contrast, they are inconsistent with Bickerton's (1981, 1984) language bioprogram hypothesis that the distinctions between state and process and between punctual and nonpunctual are preprogrammed into language learners. We suggest new ways of looking at the results in the light of recent probabilistic hypotheses that emphasize the role of input, prototypes and connectionist representations.

Abstract

Reprinted from: Bowerman, M. (1981). The child's expression of meaning: Expanding relationships among lexicon, syntax, and morphology. In H. Winitz (Ed.), Native language and foreign language acquisition (pp. 172 189). New York: New York Academy of Sciences.

Abstract

Structural priming is a useful laboratory-based technique for investigating how children respond to temporary changes in the distribution of structures in their input. In the current study we investigated whether increasing the number of object relative clauses (RCs) in German-speaking children’s input changes their processing preferences for ambiguous RCs. Fifty-one 6-year-olds and 54 9-year-olds participated in a priming task that (i) gauged their baseline interpretations for ambiguous RC structures, (ii) primed an object-RC interpretation of ambiguous RCs, and (iii) determined whether priming persevered beyond immediate prime-target pairs. The 6-year old children showed no priming effect, whereas the 9-year-old group showed robust priming that was long lasting. Unlike in studies of priming in production, priming did not increase in magnitude when there was lexical overlap between prime and target. Overall, the results suggest that increased exposure to object RCs facilitates children’s interpretation of this otherwise infrequent structure, but only in older children. The implications for acquisition theory are discussed.

Abstract

In numerous comprehension studies, across different languages, children have performed worse on object relatives (e.g., the dog that the cat chased) than on subject relatives (e.g., the dog that chased the cat). One possible reason for this is that the test sentences did not exactly match the kinds of object relatives that children typically experience. Adults and children usually hear and produce object relatives with inanimate heads and pronominal subjects (e.g., the car that we bought last year) (cf. Kidd et al., Language and Cognitive Processes 22: 860–897, 2007). We tested young 3-year old German- and English-speaking children with a referential selection task. Children from both language groups performed best in the condition where the experimenter described inanimate referents with object relatives that contained pronominal subjects (e.g., Can you give me the sweater that he bought?). Importantly, when the object relatives met the constraints identified in spoken discourse, children understood them as well as subject relatives, or even better. These results speak against a purely structural explanation for children's difficulty with object relatives as observed in previous studies, but rather support the usage-based account, according to which discourse function and experience with language shape the representation of linguistic structures.

Abstract

The current work uses memory errors to examine the mental representation of verb-particle constructions (VPCs; e.g., make up the story, cut up the meat). Some evidence suggests that VPCs are represented by a cline in which the relationship between the VPC and its component elements ranges from highly transparent (cut up) to highly idiosyncratic (make up). Other evidence supports a multiple class representation, characterizing VPCs as belonging to discretely separated classes differing in semantic and syntactic structure. We outline a novel paradigm to investigate the representation of VPCs in which we elicit illusory conjunctions, or memory errors sensitive to syntactic structure. We then use a novel application of piecewise regression to demonstrate that the resulting error pattern follows a cline rather than discrete classes. A preregistered replication verifies these findings, and a final preregistered study verifies that these errors reflect syntactic structure. This provides evidence for gradient rather than discrete representations across levels of representation in language processing.

Abstract

In work on grammatical agreement in sentence production, there are accounts of verb number formulation that emphasise the role of whole-structure properties and accounts that emphasise the role of word-driven properties. To evaluate these alternatives, we carried out two experiments that examined a referential (wholistic) contributor to agreement along with two lexical-semantic (local) factors. Both experiments gauged the accuracy and latency of inflected-verb production in order to assess how variations in grammatical number interacted with the other factors. The accuracy of verb production was modulated both by the referential effect of notional number and by the lexical-semantic effects of relatedness and category membership. As an index of agreement difficulty, latencies were little affected by either factor. The findings suggest that agreement is sensitive to referential as well as lexical forces and highlight the importance of lexical-structural integration in the process of sentence production.

Abstract

We employed a parametric psychophysical design in combination with functional imaging to examine the influence of metric changes in perceptual incongruence on perceptual alternation rates and cortical responses. Subjects viewed a bistable stimulus defined by incongruent depth cues; bistability resulted from incongruence between binocular disparity and monocular perspective cues that specify different slants (slant rivalry). Psychophysical results revealed that perceptual alternation rates were positively correlated with the degree of perceived incongruence. Functional imaging revealed systematic increases in activity that paralleled the psychophysical results within anterior intraparietal sulcus, prior to the onset of perceptual alternations. We suggest that this cortical activity predicts the frequency of subsequent alternations, implying a putative causal role for these areas in initiating bistable perception. In contrast, areas implicated in form and depth processing (LOC and V3A) were sensitive to the degree of slant, but failed to show increases in activity when these cues were in conflict.

Abstract

A major finding in studies of early vocabulary acquisition has been that children tend to learn a lot of nouns early but make do with relatively few verbs, among which semantically general-purpose verbs like do, make, get, have, give, come, go, and be play a prominent role. The preponderance of nouns is explained in terms of nouns labelling concrete objects beings “easier” to learn than verbs, which label relational categories. Nouns label “natural categories” observable in the world, verbs label more linguistically and culturally specific categories of events linking objects belonging to such natural categories (Gentner 1978, 1982; Clark 1993). This view has been challenged recently by data from children learning certain non-Indo-European languges like Korean, where children have an early verb explosion and verbs dominate in early child utterances. Children learning the Mayan language Tzeltal also acquire verbs early, prior to any noun explosion as measured by production. Verb types are roughly equivalent to noun types in children’s beginning production vocabulary and soon outnumber them. At the one-word stage children’s verbs mostly have the form of a root stripped of affixes, correctly segmented despite structural difficulties. Quite early (before the MLU 2.0 point) there is evidence of productivity of some grammatical markers (although they are not always present): the person-marking affixes cross-referencing core arguments, and the completive/incompletive aspectual distinctions. The Tzeltal facts argue against a natural-categories explanation for childre’s early vocabulary, in favor of a view emphasizing the early effects of language-specific properties of the input. They suggest that when and how a child acquires a “verb” category is centrally influenced by the structural properties of the input, and that the semantic structure of the language - where the referential load is concentrated - plays a fundamental role in addition to distributional facts.

Abstract

When Tzeltal children in the Mayan community of Tenejapa, in southern Mexico, begin speaking, their production vocabulary consists predominantly of verb roots, in contrast to the dominance of nouns in the initial vocabulary of first‐language learners of Indo‐European languages. This article proposes that a particular Tzeltal conversational feature—known in the Mayanist literature as "dialogic repetition"—provides a context that facilitates the early analysis and use of verbs. Although Tzeltal babies are not treated by adults as genuine interlocutors worthy of sustained interaction, dialogic repetition in the speech the children are exposed to may have an important role in revealing to them the structural properties of the language, as well as in socializing the collaborative style of verbal interaction adults favor in this community.

Abstract

The surge of research activity focussing on children's acquisition of verbs (e.g., Tomasello and Merriman 1996) addresses some fundamental questions: Just how variable across languages, and across individual children, is the process of verb learning? How specific are arguments to particular verbs in early child language? How does the grammatical category 'Verb' develop? The position of Universal Grammar, that a verb category is early, contrasts with that of Tomasello (1992), Pine and Lieven and their colleagues (1996, in press), and many others, that children develop a verb category slowly, gradually building up subcategorizations of verbs around pragmatic, syntactic, and semantic properties of the language they are exposed to. On this latter view, one would expect the language which the child is learning, the cultural milieu and the nature of the interactions in which the child is engaged, to influence the process of acquiring verb argument structures. This paper explores these issues by examining the development of argument representation in the Mayan language Tzeltal, in both its lexical and verbal cross-referencing forms, and analyzing the semantic and pragmatic factors influencing the form argument representation takes. Certain facts about Tzeltal (the ergative/ absolutive marking, the semantic specificity of transitive and positional verbs) are proposed to affect the representation of arguments. The first 500 multimorpheme combinations of 3 children (aged between 1;8 and 2;4) are examined. It is argued that there is no evidence of semantically light 'pathbreaking' verbs (Ninio 1996) leading the way into word combinations. There is early productivity of cross-referencing affixes marking A, S, and O arguments (although there are systematic omissions). The paper assesses the respective contributions of three kinds of factors to these results - structural (regular morphology), semantic (verb specificity) and pragmatic (the nature of Tzeltal conversational interaction).

Abstract

In this paper presents evidence of the disputed existence of an electrophysiological marker for the lexical-categorical distinction between open- and closed-class words. Event-related brain potentials were recorded from the scalp while subjects read a story. Separate waveforms were computed for open- and closed-class words. Two aspects of the waveforms could be reliably related to vocabulary class. The first was an early negativity in the 230- to 350-msec epoch, with a bilateral anterior predominance. This negativity was elicited by open- and closed-class words alike, was not affected by word frequency or word length, and had an earlier peak latency for closed-class words. The second was a frontal slow negative shift in the 350- to 500-msec epoch, largest over the left side of the scalp. This late negativity was only elicited by closed-class words. Although the early negativity cannot serve as a qualitative marker of the open- and closed-class distinction, it does reflect the earliest electrophysiological manifestation of the availability of categorical information from the mental lexicon. These results suggest that the brain honors the distinction between open- and closed-class words, in relation to the different roles that they play in on-line sentence processing.

Abstract

In reaction to the dominance of universalism in the 1970s and '80s, there have recently been a number of reappraisals of the relation between language and cognition, and the field of cognitive anthropology is flourishing in several new directions in both America and Europe. This is partly due to a renewal and re-evaluation of approaches to the question of linguistic relativity associated with Whorf, and partly to the inspiration of modern developments in cognitive science. This review briefly sketches the history of cognitive anthropology and surveys current research on both sides of the Atlantic. The focus is on assessing current directions, considering in particular, by way of illustration, recent work in cultural models and on spatial language and cognition. The review concludes with an assessment of how cognitive anthropology could contribute directly both to the broader project of cognitive science and to the anthropological study of how cultural ideas and practices relate to structures and processes of human cognition.

Abstract

Interaction, for all that it has an ethological base, is culturally constituted, and how new social members are enculturated into the interactional practices of the society is of critical interest to our understanding of interaction – how much is learned, how variable is it across cultures – as well as to our understanding of the role of culture in children’s social-cognitive development. The goal of this task is to document the nature of caregiver infant interaction in different cultures, especially during the critical age of 9-15 months when children come to have an understanding of others’ intentions. This is of interest to all students of interaction; it does not require specialist knowledge of children.

Abstract

This is a Spanish translation of Brown 1997.

Abstract

Speakers of the Mayan language Tzeltal use two frames of reference for spatial reckoning: an absolute system (based on the south/north axis abstracted from the overall slope of the land) and an intrinsic system utilizing spatial axes of the reference object to establish body parts. This paper examines the use of absolute, intrinsic, and landmark cues in descriptions of spatial relations by 22 pairs of Tzeltal children aged between 5 and 17. The data are drawn from interactive space games, where a Director describes a spatial layout in a photo and the Matcher reproduces it with toys. The paper distinguishes use of ad hoc landmarks ('Red Cliffs', 'the electricity post') from genuine absolute reference points ('uphill'/'downhill'/’across’), and shows that adults in this task use absolute ('cow uphill of horse'), intrinsic ('at the tree's side') and landmark ('cow facing Red Cliffs') descriptions to communicate the spatial relations depicted. The youngest children, however, do not use landmark cues at all but rely instead on deictics and on the absolute 'uphill/downhill' terms; landmark terms are still rare at age 8-10. Despite arguments that landmarks are a simpler, more natural, basis for spatial reckoning than absolute terms, there is no evidence for a developmental progression from landmark-based to absolute-based strategies. We relate these observations to Slobin’s ‘thinking for speaking’ argument.

Abstract

How do children isolate the semantic package contained in verb roots in the Mayan language Tzeltal? One might imagine that the canonical CVC shape of roots characteristic of Mayan languages would make the job simple, but the root is normally preceded and followed by affixes which mask its identity. Pye (1983) demonstrated that, in Kiche' Mayan, prosodic salience overrides semantic salience, and children's first words in Kiche' are often composed of only the final (stressed) syllable constituted by the final consonant of the CVC root and a 'meaningless' termination suffix. Intonation thus plays a crucial role in early Kiche' morphological development. Tzeltal presents a rather different picture: The first words of children around the age of 1;6 are bare roots, children strip off all prefixes and suffixes which are obligatory in adult speech. They gradually add them, starting with the suffixes (which receive the main stress), but person prefixes are omitted in some contexts past a child's third birthday, and one obligatory aspectual prefix (x-) is systematically omitted by the four children in my longitudinal study even after they are four years old. Tzeltal children's first verbs generally show faultless isolation of the root. An account in terms of intonation or stress cannot explain this ability (the prefixes are not all syllables; the roots are not always stressed). This paper suggests that probable clues include the fact that the CVC root stays constant across contexts (with some exceptions) whereas the affixes vary, that there are some linguistic contexts where the root occurs without any prefixes (relatively frequent in the input), and that the Tzeltal discourse convention of responding by repeating with appropriate deictic alternation (e.g., "I see it." "Oh, you see it.") highlights the root.

Abstract

This is an encyclopedia entry describing conversational and interactional uses of linguistic repetition.

Abstract

This article selectively reviews the literature on politeness across different disciplines—linguistics, anthropology, communications, conversation analysis, social psychology, and sociology—and critically assesses how both theoretical approaches to politeness and research on linguistic politeness phenomena have evolved over the past forty years. Major new developments include a shift from predominantly linguistic approaches to those examining politeness and impoliteness as processes that are embedded and negotiated in interactional and cultural contexts, as well as a greater focus on how both politeness and interactional confrontation and conflict fit into our developing understanding of human cooperation and universal aspects of human social interaction.

Abstract

This article is a reprint of chapter 1, the introduction to Brown and Levinson, 1987, Politeness: Some universals in language usage (Cambridge University Press).

Abstract

This article is a reprint of chapter 1, the introduction to Brown and Levinson, 1987, Politeness: Some universals in language usage (Cambridge University Press).

Abstract

The Noir Marron are the direct descendants of thousands of African slaves deported to the Guyanas during the Atlantic Slave Trade and later escaped mainly from Dutch colonial plantations. Six ethnic groups are officially recognized, four of which are located in French Guyana: the Aluku, the Ndjuka, the Saramaka, and the Paramaka. The aim of this study was: (1) to determine the Noir Marron settlement through genetic exchanges with other communities such as Amerindians and Europeans; (2) to retrace their origins in Africa. Buffy-coat DNA from 142 Noir Marron, currently living in French Guyana, were analyzed using mtDNA (typing of SNP coding regions and sequencing of HVSI/II) and Y chromosomes (typing STR and SNPs) to define their genetic profile. Results were compared to an African database composed by published data, updated with genotypes of 82 Fon from Benin, and 128 Ahizi and 63 Yacouba from the Ivory-Coast obtained in this study for the same markers. Furthermore, the determination of the genomic subtype of HTLV-1 strains (env gp21 and LTR regions), which can be used as a marker of migration of infected populations, was performed for samples from 23 HTLV-1 infected Noir Marron and compared with the corresponding database. MtDNA profiles showed a high haplotype diversity, in which 99% of samples belonged to the major haplogroup L, frequent in Africa. Each haplotype was largely represented on the West African coast, but notably higher homologies were obtained with the samples present in the Gulf of Guinea. Y Chromosome analysis revealed the same pattern, i.e. a conservation of the African contribution to the Noir Marron genetic profile, with 98% of haplotypes belonging to the major haplogroup E1b1a, frequent in West Africa. The genetic diversity was higher than those observed in African populations, proving the large Noir Marron’s fatherland, but a predominant identity in the Gulf of Guinea can be suggested. Concerning HTLV-1 genotyping, all the Noir Marron strains belonged to the large Cosmopolitan A subtype. However, among them 17/23 (74%) clustered with the West African clade comprizing samples originating from Ivory-Coast, Ghana, Burkina-Fasso and Senegal, while 3 others clustered in the Trans-Sahelian clade and the remaining 3 were similar to strains found in individuals in South America. Through the combined analyses of three approaches, we have provided a conclusive image of the genetic profile of the Noir Marron communities studied. The high degree of preservation of the African gene pool contradicts the expected gene flow that would correspond to the major cultural exchanges observed between Noir Marron, Europeans and Amerindians. Marital practices and historical events could explain these observations. Corresponding to historical and cultural data, the origin of the ethnic groups is widely dispatched throughout West Africa. However, all results converge to suggest an individualization from a major birthplace in the Gulf of Guinea.

Abstract

The Noir Marron communities are the direct descendants of African slaves brought to the Guianas during the four centuries (16th to 19th) of the Atlantic slave trade. Among them, three major ethnic groups have been studied: the Aluku, the Ndjuka and the Saramaka. Their history led them to share close relationships with Europeans and Amerindians, as largely documented in their cultural records. The study of Gm polymorphisms of immunoglobulins may help to estimate the amount of gene flow linked to these cultural exchanges. Surprisingly, very low levels of European contribution (2.6%) and Amerindian contribution (1.7%) are detected in the Noir Marron gene pool. On the other hand, an African contribution of 95.7% redraws their origin to West Africa (FSTless-than-or-equals, slant0.15). This highly preserved African gene pool of the Noir Marron is unique in comparison to other African American populations of Latin America, who are notably more admixed

Abstract

Lexically guided perceptual learni ng refers to the use of lexical knowledge to retune sp eech categories and thereby adapt to a novel talker’s pronunciation. This adaptation has been extensively documented, but primarily for segmental-based learning in English and Dutch. In languages with lexical tone, such as Mandarin Chinese, tonal categories can also be retuned in this way, but segmental category retuning had not been studied. We report two experiment s in which Mandarin Chinese listeners were exposed to an ambiguous mixture of [f] and [s] in lexical contexts favoring an interpretation as either [f] or [s]. Listeners were subsequently more likely to identify sounds along a continuum between [f] and [s], and to interpret minimal word pairs, in a manner consistent with this exposure. Thus lexically guided perceptual learning of segmental categories had indeed taken place, consistent with suggestions that such learning may be a universally available adaptation process

Abstract

Do all humans perceive, think, and talk about tree cover ("forests") in more or less the same way? International forestry programs frequently seem to operate on the assumption that they do. However, recent advances in the language sciences show that languages vary greatly as to how the landscape domain is lexicalized and grammaticalized. Different languages segment and label the large-scale environment and its features according to astonishingly different semantic principles, often in tandem with highly culture-specific practices and ideologies. Presumed basic concepts like mountain, valley, and river cannot in fact be straightforwardly translated across languages. In this paper we describe, compare, and evaluate some of the semantic diversity observed in relation to forests. We do so on the basis of first-hand linguistic field data from a global sample of indigenous categorization systems as they are manifested in the following languages: Avatime (Ghana), Duna (Papua New Guinea), Jahai (Malay Peninsula), Lokono (the Guianas), Makalero (East Timor), and Umpila/Kuuku Ya'u (Cape York Peninsula). We show that basic linguistic categories relating to tree cover vary considerably in their principles of semantic encoding across languages, and that forest is a challenging category from the point of view of intercultural translatability. This has consequences for current global policies and programs aimed at standardizing forest definitions and measurements. It calls for greater attention to categorial diversity in designing and implementing such agendas, and for receptiveness to and understanding of local indigenous classification systems in communicating those agendas on the ground.

Abstract

Semplates are a new descriptive and theoretical concept in lexical semantics, borne out of recent L&C work in several domains. A semplate can be defined as a configuration consisting of distinct layers of lexemes, each layer drawn from a different form class, mapped onto the same abstract semantic template. Within such a lexical layer, the sense relations between the lexical items are inherited from the underlying template. Thus, the whole set of lexical layers and the underlying template form a cross-categorial configuration in the lexicon. The goal of this task is to find new kinds of macrostructure in the lexicon, with a view to cross-linguistic comparison.

Abstract

This paper reports tentatively some features of Semnam, a Central Aslian language spoken by some 250 people in the Perak valley, Peninsular Malaysia. It outlines the unusually rich phonemic system of this hitherto undescribed language (e.g. a vowel system comprising 36 distinctive nuclei), and proposes a practical orthography for it. It also includes the c. 1,250- item wordlist on which the analysis is based, collected intermittently in the field 2006-2008.

Abstract

Large auditory-visual (AV) speech corpora are the grist of modern research in speech science, but no such corpus exists for Australian English. This is unfortunate, for speech science is the brains behind speech technology and applications such as text-to-speech (TTS) synthesis, automatic speech recognition (ASR), speaker recognition and forensic identification, talking heads, and hearing prostheses. Advances in these research areas in Australia require a large corpus of Australian English. Here the authors describe a blueprint for building the Big Australian Speech Corpus (the Big ASC), a corpus of over 1,100 speakers from urban and rural Australia, including speakers of non-indigenous, indigenous, ethnocultural, and disordered forms of Australian English, each of whom would be sampled on three occasions in a range of speech tasks designed by the researchers who would be using the corpus.

Abstract

Background: Identifying age-related changes in cognition that contribute towards reduced driving performance is important for the development of interventions to improve older adults' driving and prolong the time that they can continue to drive. While driving, one is often required to switch from attending to events changing in time, to distribute attention spatially. Although there is extensive research into both spatial attention and temporal attention and how these change with age, the literature on switching between these modalities of attention is limited within any age group. Methods: Age groups (21-30, 40-49, 50-59, 60-69 and 70+ years) were compared on their ability to switch between detecting a target in a rapid serial visual presentation (RSVP) stream and detecting a target in a visual search display. To manipulate the cost of switching, the target in the RSVP stream was either the first item in the stream (Target 1st), towards the end of the stream (Target Mid), or absent from the stream (Distractor Only). Visual search response times and accuracy were recorded. Target 1st trials behaved as no-switch trials, as attending to the remaining stream was not necessary. Target Mid and Distractor Only trials behaved as switch trials, as attending to the stream to the end was required. Results: Visual search response times (RTs) were longer on "Target Mid" and "Distractor Only" trials in comparison to "Target 1st" trials, reflecting switch-costs. Larger switch-costs were found in both the 40-49 and 60-69 years group in comparison to the 21-30 years group when switching from the Target Mid condition. Discussion: Findings warrant further exploration as to whether there are age-related changes in the ability to switch between these modalities of attention while driving. If older adults display poor performance when switching between temporal and spatial attention while driving, then the development of an intervention to preserve and improve this ability would be beneficial. © 2017 Callaghan, Holland and Kessler.

Abstract

Language comprehension engages a distributed network of frontotemporal, parietal, and sensorimotor regions, but it is still unclear how meaning of words and their semantic relationships are represented and processed within these regions and to which degrees lexico-semantic representations differ between regions and semantic types. We used fMRI and representational similarity analysis to relate word-elicited multivoxel patterns to semantic similarity between action and object words. In left inferior frontal (BA 44-45-47), left posterior middle temporal and left precentral cortex, the similarity of brain response patterns reflected semantic similarity among action-related verbs, as well as across lexical classes-between action verbs and tool-related nouns and, to a degree, between action verbs and food nouns, but not between action verbs and animal nouns. Instead, posterior inferior temporal cortex exhibited a reverse response pattern, which reflected the semantic similarity among object-related nouns, but not action-related words. These results show that semantic similarity is encoded by a range of cortical areas, including multimodal association (e.g., anterior inferior frontal, posterior middle temporal) and modality-preferential (premotor) cortex and that the representational geometries in these regions are partly dependent on semantic type, with semantic similarity among action-related words crossing lexical-semantic category boundaries.

Abstract

Dyslexia is a common specific learning disability with a substantive genetic component. Several candidate genes have been proposed to be implicated in dyslexia susceptibility, such as DYX1C1, ROBO1, KIAA0319, and DCDC2. Associations with variants in these genes have also been reported with a variety of psychometric measures tapping into the underlying processes that might be impaired in dyslexic people. In this study, we first conducted a literature review to select single nucleotide polymorphisms (SNPs) in dyslexia candidate genes that had been repeatedly implicated across studies. We then assessed the SNPs for association in the richly phenotyped longitudinal data set from the Dutch Dyslexia Program. We tested for association with several quantitative traits, including word and nonword reading fluency, rapid naming, phoneme deletion, and nonword repetition. In this, we took advantage of the longitudinal nature of the sample to examine if associations were stable across four educational time-points (from 7 to 12 years). Two SNPs in the KIAA0319 gene were nominally associated with rapid naming, and these associations were stable across different ages. Genetic association analysis with complex cognitive traits can be enriched through the use of longitudinal information on trait development.

Abstract

According to theories of embodied cognition, understanding a verb like throw involves unconsciously simulating the action throwing, using areas of the brain that support motor planning. If understanding action words involves mentally simulating our own actions, then the neurocognitive representation of word meanings should differ for people with different kinds of bodies, who perform actions in systematically different ways. In a test of the body-specificity hypothesis (Casasanto, 2009), we used fMRI to compare premotor activity correlated with action verb understanding in right- and left-handers. Right-handers preferentially activated left premotor cortex during lexical decision on manual action verbs (compared with non-manual action verbs), whereas left-handers preferentially activated right premotor areas. This finding helps refine theories of embodied semantics, suggesting that implicit mental simulation during language processing is body-specific: Right and left-handers, who perform actions differently, use correspondingly different areas of the brain for representing action verb meanings.

Abstract

Do people with different kinds of bodies think differently? According to the body-specificity hypothesis, people who interact with their physical environments in systematically different ways should form correspondingly different mental representations. In a test of this hypothesis, 5 experiments investigated links between handedness and the mental representation of abstract concepts with positive or negative valence (e.g., honesty, sadness, intelligence). Mappings from spatial location to emotional valence differed between right- and left-handed participants. Right-handers tended to associate rightward space with positive ideas and leftward space with negative ideas, but left-handers showed the opposite pattern, associating rightward space with negative ideas and leftward with positive ideas. These contrasting mental metaphors for valence cannot be attributed to linguistic experience, because idioms in English associate good with right but not with left. Rather, right- and left-handers implicitly associated positive valence more strongly with the side of space on which they could act more fluently with their dominant hands. These results support the body-specificity hypothesis and provide evidence for the perceptuomotor basis of even the most abstract ideas.

Abstract

What is the relationship between motor action and emotion? Here we investigated whether people associate good things more strongly with the dominant side of their bodies, and bad things with the non-dominant side. To find out, we analyzed spontaneous gestures during speech expressing ideas with positive or negative emotional valence (e.g., freedom, pain, compassion). Samples of speech and gesture were drawn from the 2004 and 2008 US presidential debates, which involved two left-handers (Obama, McCain) and two right-handers (Kerry, Bush). Results showed a strong association between the valence of spoken clauses and the hands used to make spontaneous co-speech gestures. In right-handed candidates, right-hand gestures were more strongly associated with positive-valence clauses, and left-hand gestures with negative-valence clauses. Left-handed candidates showed the opposite pattern. Right- and left-handers implicitly associated positive valence more strongly with their dominant hand: the hand they can use more fluently. These results support the body-specificity hypothesis, (Casasanto, 2009), and suggest a perceptuomotor basis for even our most abstract ideas.

Abstract

What is the relationship between space and time in the human mind? Studies in adults show an asymmetric relationship between mental representations of these basic dimensions of experience: representations of time depend on space more than representations of space depend on time. Here we investigated the relationship between space and time in the developing mind. Native Greek-speaking children (N=99) watched movies of two animals traveling along parallel paths for different distances or durations and judged the spatial and temporal aspects of these events (e.g., Which animal went for a longer time, or a longer distance?) Results showed a reliable cross-dimensional asymmetry: for the same stimuli, spatial information influenced temporal judgments more than temporal information influenced spatial judgments. This pattern was robust to variations in the age of the participants and the type of language used to elicit responses. This finding demonstrates a continuity between space-time representations in children and adults, and informs theories of analog magnitude representation.

Abstract

Interoperable annotation formats are fundamental to the utility, expansion, and sustainability of collective data repositories.In language development research, shared annotation schemes have been critical to facilitating the transition from raw acoustic data to searchable, structured corpora. Current schemes typically require comprehensive and manual annotation of utterance boundaries and orthographic speech content, with an additional, optional range of tags of interest. These schemes have been enormously successful for datasets on the scale of dozens of recording hours but are untenable for long-format recording corpora, which routinely contain hundreds to thousands of audio hours. Long-format corpora would benefit greatly from (semi-)automated analyses, both on the earliest steps of annotation—voice activity detection, utterance segmentation, and speaker diarization—as well as later steps—e.g., classification-based codes such as child-vs-adult-directed speech, and speech recognition to produce phonetic/orthographic representations. We present an annotation workflow specifically designed for long-format corpora which can be tailored by individual researchers and which interfaces with the current dominant scheme for short-format recordings. The workflow allows semi-automated annotation and analyses at higher linguistic levels. We give one example of how the workflow has been successfully implemented in a large cross-database project.

Abstract

Children begin developing turn-taking skills in infancy but take several years to fluidly integrate their growing knowledge of language into their turn-taking behavior. In two eye-tracking experiments, we measured children’s anticipatory gaze to upcoming responders while controlling linguistic cues to turn structure. In Experiment 1, we showed English and non-English conversations to English-speaking adults and children. In Experiment 2, we phonetically controlled lexicosyntactic and prosodic cues in English-only speech. Children spontaneously made anticipatory gaze switches by age two and continued improving through age six. In both experiments, children and adults made more anticipatory switches after hearing questions. Consistent with prior findings on adult turn prediction, prosodic information alone did not increase children’s anticipatory gaze shifts. But, unlike prior work with adults, lexical information alone was not sucient either—children’s performance was best overall with lexicosyntax and prosody together. Our findings support an account in which turn tracking and turn prediction emerge in infancy and then gradually become integrated with children’s online linguistic processing.

Abstract

Child-directed speech is argued to facilitate language development, and is found cross-linguistically and cross-culturally to varying degrees. However, previous research has generally focused on short samples of child-caregiver interaction, often in the lab or with experimenters present. We test the generalizability of this phenomenon with an initial descriptive analysis of the speech heard by young children in a large, unique collection of naturalistic, daylong home recordings. Trained annotators coded automatically-detected adult speech 'utterances' from 61 homes across 4 North American cities, gathered from children (age 2-24 months) wearing audio recorders during a typical day. Coders marked the speaker gender (male/female) and intended addressee (child/adult), yielding 10,886 addressee and gender tags from 2,523 minutes of audio (cf. HB-CHAAC Interspeech ComParE challenge; Schuller et al., in press). Automated speaker-diarization (LENA) incorrectly gender-tagged 30% of male adult utterances, compared to manually-coded consensus. Furthermore, we find effects of SES and gender on child-directed and overall speech, increasing child-directed speech with child age, and interactions of speaker gender, child gender, and child age: female caretakers increased their child-directed speech more with age than male caretakers did, but only for male infants. Implications for language acquisition and existing classification algorithms are discussed.

Abstract

Learning a specific skill during childhood may partly determine the functional organization of the adult brain. This hypothesis led us to study oral language processing in illiterate subjects who, for social reasons, had never entered school and had no knowledge of reading or writing. In a brain activation study using PET and statistical parametric mapping, we compared word and pseudoword repetition in literate and illiterate subjects. Our study confirms behavioural evidence of different phonological processing in illiterate subjects. During repetition of real words, the two groups performed similarly and activated similar areas of the brain. In contrast, illiterate subjects had more difficulty repeating pseudowords correctly and did not activate the same neural structures as literates. These results are consistent with the hypothesis that learning the written form of language (orthography) interacts with the function of oral language. Our results indicate that learning to read and write during childhood influences the functional organization of the adult human brain.

Abstract

The parietal lobe has a unique place in the human brain. Anatomically, it is at the crossroad between the frontal, occipital, and temporal lobes, thus providing a middle ground for multimodal sensory integration. Functionally, it supports higher cognitive functions that are characteristic of the human species, such as mathematical cognition, semantic and pragmatic aspects of language, and abstract thinking. Despite its importance, a comprehensive comparison of human and simian intraparietal networks is missing.

In this study, we used diffusion imaging tractography to reconstruct the major intralobar parietal tracts in twenty-one datasets acquired in vivo from healthy human subjects and eleven ex vivo datasets from five vervet and six macaque monkeys. Three regions of interest (postcentral gyrus, superior parietal lobule and inferior parietal lobule) were used to identify the tracts. Surface projections were reconstructed for both species and results compared to identify similarities or differences in tract anatomy (i.e., trajectories and cortical projections). In addition, post-mortem dissections were performed in a human brain.

The largest tract identified in both human and monkey brains is a vertical pathway between the superior and inferior parietal lobules. This tract can be divided into an anterior (supramarginal gyrus) and a posterior (angular gyrus) component in both humans and monkey brains. The second prominent intraparietal tract connects the postcentral gyrus to both supramarginal and angular gyri of the inferior parietal lobule in humans but only to the supramarginal gyrus in the monkey brain. The third tract connects the postcentral gyrus to the anterior region of the superior parietal lobule and is more prominent in monkeys compared to humans. Finally, short U-shaped fibres in the medial and lateral aspects of the parietal lobe were identified in both species. A tract connecting the medial parietal cortex to the lateral inferior parietal cortex was observed in the monkey brain only.

Our findings suggest a consistent pattern of intralobar parietal connections between humans and monkeys with some differences for those areas that have cytoarchitectonically distinct features in humans. The overall pattern of intraparietal connectivity supports the special role of the inferior parietal lobule in cognitive functions characteristic of humans.

Abstract

In this paper we explore the feasibility of artificial (formal) grammar recognition (AGR) using spiking neural networks. A biologically inspired minicolumn architecture is designed as the basic computational unit. A network topography is defined based on the minicolumn architecture, here referred to as nodes, connected with excitatory and inhibitory connections. Nodes in the network represent unique internal states of the grammar’s finite state machine (FSM). Future work to improve the performance of the networks is discussed. The modeling framework developed can be used by neurophysiological research to implement network layouts and compare simulated performance characteristics to actual subject performance.

Abstract

RNA interference (RNAi) is a set of mechanisms which regulate gene expression in eukaryotes. Key elements of RNAi are small sense and antisense RNAs from 19 to 26 nucleotides generated from double-stranded RNAs. miRNAs are a major type of RNAi-associated small RNAs and are found in most eukaryotes studied to date. To investigate whether small RNAs associated with RNAi appear to be present in all eukaryotic lineages, and therefore present in the ancestral eukaryote, we studied two deep-branching protozoan parasites, Giardia intestinalis and Trichomonas vaginalis. Little is known about endogenous small RNAs involved in RNAi of these organisms. Using Illumina Solexa sequencing and genome-wide analysis of small RNAs from these distantly related deep-branching eukaryotes, we identified 10 strong miRNA candidates from Giardia and 11 from Trichomonas. We also found evidence of Giardia siRNAs potentially involved in the expression of variant-specific-surface proteins. In addition, 8 new snoRNAs from Trichomonas are identified. Our results indicate that miRNAs are likely to be general in ancestral eukaryotes, and therefore are likely to be a universal feature of eukaryotes.

Abstract

This paper investigates L2 learners’ use of intonation in reference maintenance in comparison to native speakers at three longitudinal points. Nominal referring expressions were elicited from two untutored Turkish learners of Dutch and five native speakers of Dutch via a film retelling task, and were analysed in terms of pitch span and word duration. Effects of two types of change in information states were examined, between new and given and between new and accessible. We found native-like use of word duration in both types of change early on but different performances between learners and development over time in one learner in the use of pitch span. Further, the use of morphosyntactic devices had different effects on the two learners. The inter-learner differences and late systematic use of pitch span, in spite of similar use of pitch span in learners’ L1 and L2, suggest that learning may play a role in the acquisition of intonation as a device for reference maintenance.

Abstract

A significant proportion of children have unexplained problems acquiring proficient linguistic skills despite adequate intelligence and opportunity. Developmental language disorders are highly heritable with substantial societal impact. Molecular studies have begun to identify candidate loci, but much of the underlying genetic architecture remains undetermined. We performed whole-exome sequencing of 43 unrelated probands affected by severe specific language impairment, followed by independent validations with Sanger sequencing, and analyses of segregation patterns in parents and siblings, to shed new light on aetiology. By first focusing on a pre-defined set of known candidates from the literature, we identified potentially pathogenic variants in genes already implicated in diverse language-related syndromes, including ERC1, GRIN2A, and SRPX2. Complementary analyses suggested novel putative candidates carrying validated variants which were predicted to have functional effects, such as OXR1, SCN9A and KMT2D. We also searched for potential “multiple-hit” cases; one proband carried a rare AUTS2 variant in combination with a rare inherited haplotype affecting STARD9, while another carried a novel nonsynonymous variant in SEMA6D together with a rare stop-gain in SYNPR. On broadening scope to all rare and novel variants throughout the exomes, we identified biological themes that were enriched for such variants, including microtubule transport and cytoskeletal regulation.

Abstract

This paper reports a perceptual study using a semantically motivated identification task in which we investigated the nature of two pairs of intonational contrasts in English: (1) normal High accent vs. emphatic High accent; (2) early peak alignment vs. late peak alignment. Unlike previous inquiries, the present study employs an on-line method using the Reaction Time measurement, in addition to the measurement of response frequencies. Regarding the peak height continuum, the mean RTs are shortest for within-category identification but longest for across-category identification. As for the peak alignment contrast, no identification boundary emerges and the mean RTs only reflect a difference between peaks aligned with the vowel onset and peaks aligned elsewhere. We conclude that the peak height contrast is discrete but the previously claimed discreteness of the peak alignment contrast is not borne out.

Abstract

This study examines the effects of prosodic boundaries, lexical stress, and phrasal accent on the acoustic realization of stops (/t, d/) in Dutch, with special attention paid to language-specificity in the phonetics-prosody interface. The results obtained from various acoustic measures show systematic phonetic variations in the production of /t d/ as a function of prosodic position, which may be interpreted as being due to prosodicallyconditioned articulatory strengthening. Shorter VOTs were found for the voiceless stop /t/ in prosodically stronger locations (as opposed to longer VOTs in this position in English). The results suggest that prosodically-driven phonetic realization is bounded by a language-specific phonological feature system.

Abstract

Children adopted early in life into another linguistic community typically forget their birth language but retain, unaware, relevant linguistic knowledge that may facilitate (re)learning of birth-language patterns. Understanding the nature of this knowledge can shed light on how language is acquired. Here, international adoptees from Korea with Dutch as their current language, and matched Dutch-native controls, provided speech production data on a Korean consonantal distinction unlike any Dutch distinctions, at the outset and end of an intensive perceptual training. The productions, elicited in a repetition task, were identified and rated by Korean listeners. Adoptees' production scores improved significantly more across the training period than control participants' scores, and, for adoptees only, relative production success correlated significantly with the rate of learning in perception (which had, as predicted, also surpassed that of the controls). Of the adoptee group, half had been adopted at 17 months or older (when talking would have begun), while half had been prelinguistic (under six months). The former group, with production experience, showed no advantage over the group without. Thus the adoptees' retained knowledge of Korean transferred from perception to production and appears to be abstract in nature rather than dependent on the amount of experience.

Abstract

Until at least 6 mo of age, infants show good discrimination for familiar phonetic contrasts (i.e., those heard in the environmental language) and contrasts that are unfamiliar. Adult-like discrimination (significantly worse for nonnative than for native contrasts) appears only later, by 9–10 mo. This has been interpreted as indicating that infants have no knowledge of phonology until vocabulary development begins, after 6 mo of age. Recently, however, word recognition has been observed before age 6 mo, apparently decoupling the vocabulary and phonology acquisition processes. Here we show that phonological acquisition is also in progress before 6 mo of age. The evidence comes from retention of birth-language knowledge in international adoptees. In the largest ever such study, we recruited 29 adult Dutch speakers who had been adopted from Korea when young and had no conscious knowledge of Korean language at all. Half were adopted at age 3–5 mo (before native-specific discrimination develops) and half at 17 mo or older (after word learning has begun). In a short intensive training program, we observe that adoptees (compared with 29 matched controls) more rapidly learn tripartite Korean consonant distinctions without counterparts in their later-acquired Dutch, suggesting that the adoptees retained phonological knowledge about the Korean distinction. The advantage is equivalent for the younger-adopted and the older-adopted groups, and both groups not only acquire the tripartite distinction for the trained consonants but also generalize it to untrained consonants. Although infants younger than 6 mo can still discriminate unfamiliar phonetic distinctions, this finding indicates that native-language phonological knowledge is nonetheless being acquired at that age.

Abstract

This study investigates young children’s comprehension of spatial terms in two languages that categorize space strikingly differently. English makes a distinction between actions resulting in containment (put in) versus support or surface attachment (put on), while Korean makes a cross-cutting distinction between tight-fit relations (kkita) versus loose-fit or other contact relations (various verbs). In particular, the Korean verb kkita refers to actions resulting in a tight-fit relation regardless of containment or support. In a preferential looking study we assessed the comprehension of in by 20 English learners and kkita by 10 Korean learners, all between 18 and 23 months. The children viewed pairs of scenes while listening to sentences with and without the target word. The target word led children to gaze at different and language-appropriate aspects of the scenes. We conclude that children are sensitive to language-specific spatial categories by 18–23 months.

Abstract

In the current paper, we asked at what level in the speech planning process speakers retrieve stored syllables. There is evidence that syllable structure plays an essential role in the phonological encoding of words (e.g., online syllabification and phonological word formation). There is also evidence that syllables are retrieved as whole units. However, findings that clearly pinpoint these effects to specific levels in speech planning are scarce. We used a naming variant of the implicit priming paradigm to contrast voice onset latencies for frequency-manipulated disyllabic Dutch pseudo-words. While prior implicit priming studies only manipulated the item's form and/or syllable structure overlap we introduced syllable frequency as an additional factor. If the preparation effect for syllables obtained in the implicit priming paradigm proceeds beyond phonological planning, i.e., includes the retrieval of stored syllables, then the preparation effect should differ for high- and low frequency syllables. The findings reported here confirm this prediction: Low-frequency syllables benefit significantly more from the preparation than high-frequency syllables. Our findings support the notion of a mental syllabary at a post-lexical level, between the levels of phonological and phonetic encoding.

Abstract

When we speak, we spontaneously produce gestures (co-speech gestures). Co-speech gestures and speech production are closely interlinked. However, the exact nature of the link is still under debate. To addressed the question that whether co-speech gestures originate from the speech production system or from a system independent of the speech production, the present study examined the relationship between co-speech and co-thought gestures. Co-thought gestures, produced during silent thinking without speaking, presumably originate from a system independent of the speech production processes. We found a positive correlation between the production frequency of co-thought and co-speech gestures, regardless the communicative function that co-speech gestures might serve. Therefore, we suggest that co-speech gestures and co-thought gestures originate from a common system that is independent of the speech production processes

Abstract

Koriat (1981) demonstrated that an association from the target to a preceding prime, in the absence of an association from the prime to the target, facilitates lexical decision and referred to this effect as "backward priming". Backward priming is of relevance, because it can provide information about the mechanism underlying semantic priming effects. Following Neely (1991), we distinguish three mechanisms of priming: spreading activation, expectancy, and semantic matching/integration. The goal was to determine which of these mechanisms causes backward priming, by assessing effects of backward priming on a language-relevant ERP component, the N400, and reaction time (RT). Based on previous work, we propose that the N400 priming effect reflects expectancy and semantic matching/integration, but in contrast with RT does not reflect spreading activation. Experiment 1 shows a backward priming effect that is qualitatively similar for the N400 and RT in a lexical decision task. This effect was not modulated by an ISI manipulation. Experiment 2 clarifies that the N400 backward priming effect reflects genuine changes in N400 amplitude and cannot be ascribed to other factors. We will argue that these backward priming effects cannot be due to expectancy but are best accounted for in terms of semantic matching/integration.

Abstract

Clashen proposes two distinct processing routes, for regularly and irregularly inflected forms, respectively, and thus is apparently making a psychological claim. We argue his position, which embodies a strictly linguistic perspective, does not constitute a psychological processing model.

Abstract

Expectancy mechanisms are routinely used by the cognitive system in stimulus processing and in anticipation of appropriate responses. Electrophysiology research has documented negative shifts of brain activity when expectancies are violated within a local stimulus context (e.g., reading an implausible word in a sentence) or more globally between consecutive stimuli (e.g., a narrative of images with an incongruent end). In this EEG study, we examine the interaction between expectancies operating at the level of stimulus plausibility and at more global level of contextual congruency to provide evidence for, or against, a disassociation of the underlying processing mechanisms. We asked participants to verify the congruency of pairs of cross-modal stimuli (a sentence and a scene), which varied in plausibility. ANOVAs on ERP amplitudes in selected windows of interest show that congruency violation has longer-lasting (from 100 to 500 ms) and more widespread effects than plausibility violation (from 200 to 400 ms). We also observed critical interactions between these factors, whereby incongruent and implausible pairs elicited stronger negative shifts than their congruent counterpart, both early on (100–200 ms) and between 400–500 ms. Our results suggest that the integration mechanisms are sensitive to both global and local effects of expectancy in a modality independent manner. Overall, we provide novel insights into the interdependence of expectancy during meaning integration of cross-modal stimuli in a verification task

Abstract

Our knowledge of RNA biology within eukaryotes has exploded over the last five years. Within new research we see that some features that were once thought to be part of multicellular life have now been identified in several protist lineages. Hence, it is timely to ask which features of eukaryote RNA biology are ancestral to all eukaryotes. We focus on RNA-based regulation and epigenetic mechanisms that use small regulatory ncRNAs and long ncRNAs, to highlight some of the many questions surrounding eukaryotic ncRNA evolution.

Abstract

Past events like fluctuations in population size and post-glacial colonization processes may influence the relative importance of genetic drift, migration and selection when determining the present day patterns of genetic variation. We disentangle how drift, selection and migration shape neutral and adaptive genetic variation in 12 moor frog populations along a 1700 km latitudinal gradient. We studied genetic differentiation and variation at a MHC exon II locus and a set of 18 microsatellites.
Results

Using outlier analyses, we identified the MHC II exon 2 (corresponding to the β-2 domain) locus and one microsatellite locus (RCO8640) to be subject to diversifying selection, while five microsatellite loci showed signals of stabilizing selection among populations. STRUCTURE and DAPC analyses on the neutral microsatellites assigned populations to a northern and a southern cluster, reflecting two different post-glacial colonization routes found in previous studies. Genetic variation overall was lower in the northern cluster. The signature of selection on MHC exon II was weaker in the northern cluster, possibly as a consequence of smaller and more fragmented populations.
Conclusion

Our results show that historical demographic processes combined with selection and drift have led to a complex pattern of differentiation along the gradient where some loci are more divergent among populations than predicted from drift expectations due to diversifying selection, while other loci are more uniform among populations due to stabilizing selection. Importantly, both overall and MHC genetic variation are lower at northern latitudes. Due to lower evolutionary potential, the low genetic variation in northern populations may increase the risk of extinction when confronted with emerging pathogens and climate change.

Abstract

In three experiments, listeners detected vowel or consonant targets in lists of CV syllables constructed from five vowels and five consonants. Responses were faster in a predictable context (e.g., listening for a vowel target in a list of syllables all beginning with the same consonant) than in an unpredictable context (e.g., listening for a vowel target in a list of syllables beginning with different consonants). In Experiment 1, the listeners’ native language was Dutch, in which vowel and consonant repertoires are similar in size. The difference between predictable and unpredictable contexts was comparable for vowel and consonant targets. In Experiments 2 and 3, the listeners’ native language was Spanish, which has four times as many consonants as vowels; here effects of an unpredictable consonant context on vowel detection were significantly greater than effects of an unpredictable vowel context on consonant detection. This finding suggests that listeners’ processing of phonemes takes into account the constitution of their language’s phonemic repertoire and the implications that this has for contextual variability.

Abstract

This study tested the hypothesis that cooperative breeding facilitates the emergence of prosocial behavior by presenting cottontop tamarins (Saguinus oedipus) with the option to provide food rewards to pair-bonded mates. In Experiment 1, tamarins could provide rewards to mates at no additional cost while obtaining rewards for themselves. Contrary to the hypothesis, tamarins did not demonstrate a preference to donate rewards, behaving similar to chimpanzees in previous studies. In Experiment 2, the authors eliminated rewards for the donor for a stricter test of prosocial behavior, while reducing separation distress and food preoccupation. Again, the authors found no evidence for a donation preference. Furthermore, tamarins were significantly less likely to deliver rewards to mates when the mate displayed interest in the reward. The results of this study contrast with those recently reported for cooperatively breeding common marmosets, and indicate that prosocial preferences in a food donation task do not emerge in all cooperative breeders. In previous studies, cottontop tamarins have cooperated and reciprocated to obtain food rewards; the current findings sharpen understanding of the boundaries of cottontop tamarins’ food-provisioning behavior.