Publications

Displaying 1 - 20 of 339
  • Acerbi, A., Van Leeuwen, E. J. C., Haun, D. B. M., & Tennie, C. (2016). Conformity cannot be identified based on population-level signatures. Scientific Reports, 6: 36068. doi:10.1038/srep36068.

    Abstract

    Conformist transmission, defined as a disproportionate likelihood to copy the majority, is considered a potent mechanism underlying the emergence and stabilization of cultural diversity. However, ambiguity within and across disciplines remains as to how to identify conformist transmission empirically. In most studies, a population level outcome has been taken as the benchmark to evidence conformist transmission: a sigmoidal relation between individuals’ probability to copy the majority and the proportional majority size. Using an individual-based model, we show that, under ecologically plausible conditions, this sigmoidal relation can also be detected without equipping individuals with a conformist bias. Situations in which individuals copy randomly from a fixed subset of demonstrators in the population, or in which they have a preference for one of the possible variants, yield similar sigmoidal patterns as a conformist bias would. Our findings warrant a revisiting of studies that base their conformist transmission conclusions solely on the sigmoidal curve. More generally, our results indicate that population level outcomes interpreted as conformist transmission could potentially be explained by other individual-level strategies, and that more empirical support is needed to prove the existence of an individual-level conformist bias in human and other animals.
  • Adams, H. H. H., Hibar, D. P., Chouraki, V., Stein, J. L., Nyquist, P., Renteria, M. E., Trompet, S., Arias-Vasquez, A., Seshadri, S., Desrivières, S., Beecham, A. H., Jahanshad, N., Wittfeld, K., Van der Lee, S. J., Abramovic, L., Alhusaini, S., Amin, N., Andersson, M., Arfanakis, K. A., Aribisala, B. S., Armstrong, N. J., Athanasiu, L., Axelsson, T., Beiser, A., Bernard, M., Bis, J. C., Blanken, L. M. E., Blanton, S. H., Bohlken, M. M., Boks, M. P., Bralten, J., Brickman, A. M., Carmichael, O., Chakravarty, M. M., Chauhan, G., Chen, Q., Ching, C. R. K., Cuellar-Partida, G., Den Braber, A., Doan, N. T., Ehrlich, S., Filippi, I., Ge, T., Giddaluru, S., Goldman, A. L., Gottesman, R. F., Greven, C. U., Grimm, O., Griswold, M. E., Guadalupe, T., Hass, J., Haukvik, U. K., Hilal, S., Hofer, E., Höhn, D., Holmes, A. J., Hoogman, M., Janowitz, D., Jia, T., Karbalai, N., Kasperaviciute, D., Kim, S., Klein, M., Krämer, B., Lee–, P. H., Liao, J., Liewald, D. C. M., Lopez, L. M., Luciano, M., Macare, C., Marquand, A., Matarin, M., Mather, K. A., Mattheisen, M., Mazoyer, B., McKay, D. R., McWhirter, R., Milaneschi, Y., Muetzel, R. L., Muñoz Maniega, S., Nho, K., Nugent, A. C., Olde Loohuis, L. M., Oosterlaan, J., Papmeyer, M., Pappa, I., Pirpamer, L., Pudas, S., Pütz, B., Rajan, K. B., Ramasamy, A., Richards, J. S., Risacher, S. L., Roiz-Santiañez, R., Rommelse, N., Rose, E. J., Royle, N. A., Rundek, T., Sämann, P. G., Satizabal, C. L., Schmaal, L., Schork, A. J., Shen, L., Shin, J., Shumskaya, E., Smith, A. V., Sprooten, E., Strike, L. T., Teumer, A., Thomson, R., Tordesillas-Gutierrez, D., Toro, R., Trabzuni, D., Vaidya, D., Van der Grond, J., Van der Meer, D., Van Donkelaar, M. M. J., Van Eijk, K. R., VanErp, T. G. M., Van Rooij, D., Walton, E., Westlye, L. T., Whelan, C. D., Windham, B. G., Winkler, A. M., Woldehawariat, G., Wolf, C., Wolfers, T., Xu, B., Yanek, L. R., Yang, J., Zijdenbos, A., Zwiers, M. P., Agartz, I., Aggarwal, N. T., Almasy, L., Ames, D., Amouyel, P., Andreassen, O. A., Arepalli, S., Assareh, A. A., Barral, S., Bastin, M. E., Becker, J. T., Becker, D. M., Bennett, D. A., Blangero, J., Van Bokhoven, H., Boomsma, D. I., Brodaty, H., Brouwer, R. M., Brunner, H. G., Buckner, R. L., Buitelaar, J. K., Bulayeva, K. B., Cahn, W., Calhoun, V. D., Cannon, D. M., Cavalleri, G. L., Chen, C., Cheng, C.-Y., Cichon, S., Cookson, M. R., Corvin, A., Crespo-Facorro, B., Curran, J. E., Czisch, M., Dale, A. M., Davies, G. E., De Geus, E. J. C., De Jager, P. L., De Zubicaray, G. I., Delanty, N., Depondt, C., DeStefano, A., Dillman, A., Djurovic, S., Donohoe, G., Drevets, W. C., Duggirala, R., Dyer, T. D., Erk, S., Espeseth, T., Evans, D. A., Fedko, I. O., Fernández, G., Ferrucci, L., Fisher, S. E., Fleischman, D. A., Ford, I., Foroud, T. M., Fox, P. T., Francks, C., Fukunaga, M., Gibbs, J. R., Glahn, D. C., Gollub, R. L., Göring, H. H. H., Grabe, H. J., Green, R. C., Gruber, O., Guelfi, S., Hansell, N. K., Hardy, J., Hartman, C. A., Hashimoto, R., Hegenscheid, K., Heinz, A., Le Hellard, S., Hernandez, D. G., Heslenfeld, D. J., Ho, B.-C., Hoekstra, P. J., Hoffmann, W., Hofman, A., Holsboer, F., Homuth, G., Hosten, N., Hottenga, J.-J., Hulshoff Pol, H. E., Ikeda, M., Ikram, M. K., Jack Jr, C. R., Jenkinson, M., Johnson, R., Jönsson, E. G., Jukema, J. W., Kahn, R. S., Kanai, R., Kloszewska, I., Knopman, D. S., Kochunov, P., Kwok, J. B., Launer, L. J., Lawrie, S. M., Lemaître, H., Liu, X., Longo, D. L., Longstreth Jr, W. T., Lopez, O. L., Lovestone, S., Martinez, O., Martinot, J.-L., Mattay, V. S., McDonald, C., McIntosh, A. M., McMahon, F. J., McMahon, K. L., Mecocci, P., Melle, I., Meyer-Lindenberg, A., Mohnke, S., Montgomery, G. W., Morris, D. W., Mosley, T. H., Mühleisen, T. W., Müller-Myhsok, B., Nalls, M. A., Nauck, M., Nichols, T. E., Niessen, W. J., Nöthen, M. M., Nyberg, L., Ohi, K., Olvera, R. L., Ophoff, R. A., Pandolfo, M., Paus, T., Pausova, Z., Penninx, B. W. J. H., Pike, G. B., Potkin, S. G., Psaty, B. M., Reppermund, S., Rietschel, M., Roffman, J. L., Romanczuk-Seiferth, N., Rotter, J. I., Ryten, M., Sacco, R. L., Sachdev, P. S., Saykin, A. J., Schmidt, R., Schofield, P. R., Sigursson, S., Simmons, A., Singleton, A., Sisodiya, S. M., Smith, C., Smoller, J. W., Soininen, H., Srikanth, V., Steen, V. M., Stott, D. J., Sussmann, J. E., Thalamuthu, A., Tiemeier, H., Toga, A. W., Traynor, B., Troncoso, J., Turner, J. A., Tzourio, C., Uitterlinden, A. G., Valdés Hernández, M. C., Van der Brug, M., Van der Lugt, A., Van der Wee, N. J. A., Van Duijn, C. M., Van Haren, N. E. M., Van 't Ent, D., Van Tol, M.-J., Vardarajan, B. N., Veltman, D. J., Vernooij, M. W., Völzke, H., Walter, H., Wardlaw, J. M., Wassink, T. H., Weale, M. E., Weinberger, D. R., Weiner, M. W., Wen, W., Westman, E., White, T., Wong, T. Y., Wright, C. B., Zielke, R. H., Zonderman, A. B., the Alzheimer's Disease Neuroimaging Initiative, EPIGEN, IMAGEN, SYS, Deary, I. J., DeCarli, C., Schmidt, H., Martin, N. G., De Craen, A. J. M., Wright, M. J., Gudnason, V., Schumann, G., Fornage, M., Franke, B., Debette, S., Medland, S. E., Ikram, M. A., & Thompson, P. M. (2016). Novel genetic loci underlying human intracranial volume identified through genome-wide association. Nature Neuroscience, 19, 1569-1582. doi:10.1038/nn.4398.

    Abstract

    Intracranial volume reflects the maximally attained brain size during development, and remains stable with loss of tissue in late life. It is highly heritable, but the underlying genes remain largely undetermined. In a genome-wide association study of 32,438 adults, we discovered five previously unknown loci for intracranial volume and confirmed two known signals. Four of the loci were also associated with adult human stature, but these remained associated with intracranial volume after adjusting for height. We found a high genetic correlation with child head circumference (genetic = 0.748), which indicates a similar genetic background and allowed us to identify four additional loci through meta-analysis (Ncombined = 37,345). Variants for intracranial volume were also related to childhood and adult cognitive function, and Parkinson’s disease, and were enriched near genes involved in growth pathways, including PI3K-AKT signaling. These findings identify the biological underpinnings of intracranial volume and provide genetic support for theories on brain reserve and brain overgrowth.
  • Aebi, M., Van Donkelaar, M. M. J., Poelmans, G., Buitelaar, J. K., Sonuga-Barke, E. J., Stringaris, A., Consortium, I., Faraone, S. V., Franke, B., Steinhausen, H. C., & van Hulzen, K. J. (2016). Gene-set and multivariate genome-wide association analysis of oppositional defiant behavior subtypes in attention-deficit/hyperactivity disorder. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 171(5), 573-88. doi:10.1002/ajmg.b.32346.

    Abstract

    Oppositional defiant disorder (ODD) is a frequent psychiatric disorder seen in children and adolescents with attention-deficit-hyperactivity disorder (ADHD). ODD is also a common antecedent to both affective disorders and aggressive behaviors. Although the heritability of ODD has been estimated to be around 0.60, there has been little research into the molecular genetics of ODD. The present study examined the association of irritable and defiant/vindictive dimensions and categorical subtypes of ODD (based on latent class analyses) with previously described specific polymorphisms (DRD4 exon3 VNTR, 5-HTTLPR, and seven OXTR SNPs) as well as with dopamine, serotonin, and oxytocin genes and pathways in a clinical sample of children and adolescents with ADHD. In addition, we performed a multivariate genome-wide association study (GWAS) of the aforementioned ODD dimensions and subtypes. Apart from adjusting the analyses for age and sex, we controlled for "parental ability to cope with disruptive behavior." None of the hypothesis-driven analyses revealed a significant association with ODD dimensions and subtypes. Inadequate parenting behavior was significantly associated with all ODD dimensions and subtypes, most strongly with defiant/vindictive behaviors. In addition, the GWAS did not result in genome-wide significant findings but bioinformatics and literature analyses revealed that the proteins encoded by 28 of the 53 top-ranked genes functionally interact in a molecular landscape centered around Beta-catenin signaling and involved in the regulation of neurite outgrowth. Our findings provide new insights into the molecular basis of ODD and inform future genetic studies of oppositional behavior. (c) 2015 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.
  • Alday, P. M. (2016). Towards a rigorous motivation for Ziph's law. In S. G. Roberts, C. Cuskley, L. McCrohon, L. Barceló-Coblijn, O. Feher, & T. Verhoef (Eds.), The Evolution of Language: Proceedings of the 11th International Conference (EVOLANG11). Retrieved from http://evolang.org/neworleans/papers/178.html.

    Abstract

    Language evolution can be viewed from two viewpoints: the development of a communicative system and the biological adaptations necessary for producing and perceiving said system. The communicative-system vantage point has enjoyed a wealth of mathematical models based on simple distributional properties of language, often formulated as empirical laws. However, be- yond vague psychological notions of “least effort”, no principled explanation has been proposed for the existence and success of such laws. Meanwhile, psychological and neurobiological mod- els have focused largely on the computational constraints presented by incremental, real-time processing. In the following, we show that information-theoretic entropy underpins successful models of both types and provides a more principled motivation for Zipf’s Law
  • Alhama, R. G., & Zuidema, W. (2016). Generalization in Artificial Language Learning: Modelling the Propensity to Generalize. In Proceedings of the 7th Workshop on Cognitive Aspects of Computational Language Learning (pp. 64-72). Association for Computational Linguistics. doi:10.18653/v1/W16-1909.

    Abstract

    Experiments in Artificial Language Learn- ing have revealed much about the cogni- tive mechanisms underlying sequence and language learning in human adults, in in- fants and in non-human animals. This pa- per focuses on their ability to generalize to novel grammatical instances (i.e., in- stances consistent with a familiarization pattern). Notably, the propensity to gen- eralize appears to be negatively correlated with the amount of exposure to the artifi- cial language, a fact that has been claimed to be contrary to the predictions of statis- tical models (Pe ̃ na et al. (2002); Endress and Bonatti (2007)). In this paper, we pro- pose to model generalization as a three- step process, and we demonstrate that the use of statistical models for the first two steps, contrary to widespread intuitions in the ALL-field, can explain the observed decrease of the propensity to generalize with exposure time.
  • Alhama, R. G., & Zuidema, W. (2016). Pre-Wiring and Pre-Training: What does a neural network need to learn truly general identity rules? In T. R. Besold, A. Bordes, & A. D'Avila Garcez (Eds.), CoCo 2016 Cognitive Computation: Proceedings of the Workshop on Cognitive Computation: Integrating neural and symbolic approaches 2016. CEUR Workshop Proceedings.

    Abstract

    In an influential paper, Marcus et al. [1999] claimed that connectionist models cannot account for human success at learning tasks that involved generalization of abstract knowledge such as grammatical rules. This claim triggered a heated debate, centered mostly around variants of the Simple Recurrent Network model [Elman, 1990]. In our work, we revisit this unresolved debate and analyze the underlying issues from a different perspective. We argue that, in order to simulate human-like learning of grammatical rules, a neural network model should not be used as a tabula rasa , but rather, the initial wiring of the neural connections and the experience acquired prior to the actual task should be incorporated into the model. We present two methods that aim to provide such initial state: a manipu- lation of the initial connections of the network in a cognitively plausible manner (concretely, by implementing a “delay-line” memory), and a pre-training algorithm that incrementally challenges the network with novel stimuli. We implement such techniques in an Echo State Network [Jaeger, 2001], and we show that only when combining both techniques the ESN is able to learn truly general identity rules.
  • Ambridge, B., Bidgood, A., Pine, J. M., & Rowland, C. F. (2016). Is Passive Syntax Semantically Constrained? Evidence From Adult Grammaticality Judgment and Comprehension Studies. Cognitive Science, 40, 1435-1459. doi:10.1111/cogs.12277.

    Abstract

    To explain the phenomenon that certain English verbs resist passivization (e.g., *£5 was cost by the book), Pinker (1989) proposed a semantic constraint on the passive in the adult grammar: The greater the extent to which a verb denotes an action where a patient is affected or acted upon, the greater the extent to which it is compatible with the passive. However, a number of comprehension and production priming studies have cast doubt upon this claim, finding no difference between highly affecting agent-patient/theme-experiencer passives (e.g., Wendy was kicked/frightened by Bob) and non-actional experiencer theme passives (e.g., Wendy was heard by Bob). The present study provides evidence that a semantic constraint is psychologically real, and is readily observed when more fine-grained independent and dependent measures are used (i.e., participant ratings of verb semantics, graded grammaticality judgments, and reaction time in a forced-choice picture-matching comprehension task). We conclude that a semantic constraint on the passive must be incorporated into accounts of the adult grammar.

    Supplementary material

    cogs12277-sup-0001-DataS1-S2.docx
  • Araújo, S., Faísca, L., Reis, A., Marques, J. F., & Petersson, K. M. (2016). Visual naming deficits in dyslexia: An ERP investigation of different processing domains. Neuropsychologia, 91, 61-76. doi:10.1016/j.neuropsychologia.2016.07.007.

    Abstract

    Naming speed deficits are well documented in developmental dyslexia, expressed by slower naming times and more errors in response to familiar items. Here we used event-related potentials (ERPs) to examine at what processing level the deficits in dyslexia emerge during a discrete-naming task. Dyslexic and skilled adult control readers performed a primed object-naming task, in which the relationship between the prime and the target was manipulated along perceptual, semantic and phonological dimensions. A 3×2 design that crossed Relationship Type (Visual, Phonemic Onset, and Semantic) with Relatedness (Related and Unrelated) was used. An attenuated N/P190 – indexing early visual processing – and N300 – which index late visual processing – was observed to pictures preceded by perceptually related (vs. unrelated) primes in the control but not in the dyslexic group. These findings suggest suboptimal processing in early stages of object processing in dyslexia, when integration and mapping of perceptual information to a more form-specific percept in memory take place. On the other hand, both groups showed an N400 effect associated with semantically related pictures (vs. unrelated), taken to reflect intact integration of semantic similarities in both dyslexic and control readers. We also found an electrophysiological effect of phonological priming in the N400 range – that is, an attenuated N400 to objects preceded by phonemic related primes vs. unrelated – while it showed a more widespread distributed and more pronounced over the right hemisphere in the dyslexics. Topographic differences between groups might have originated from a word form encoding process with different characteristics in dyslexics compared to control readers.
  • Asaridou, S. S., Takashima, A., Dediu, D., Hagoort, P., & McQueen, J. M. (2016). Repetition suppression in the left inferior frontal gyrus predicts tone learning performance. Cerebral Cortex, 26(6), 2728-2742. doi:10.1093/cercor/bhv126.

    Abstract

    Do individuals differ in how efficiently they process non-native sounds? To what extent do these differences relate to individual variability in sound-learning aptitude? We addressed these questions by assessing the sound-learning abilities of Dutch native speakers as they were trained on non-native tone contrasts. We used fMRI repetition suppression to the non-native tones to measure participants' neuronal processing efficiency before and after training. Although all participants improved in tone identification with training, there was large individual variability in learning performance. A repetition suppression effect to tone was found in the bilateral inferior frontal gyri (IFGs) before training. No whole-brain effect was found after training; a region-of-interest analysis, however, showed that, after training, repetition suppression to tone in the left IFG correlated positively with learning. That is, individuals who were better in learning the non-native tones showed larger repetition suppression in this area. Crucially, this was true even before training. These findings add to existing evidence that the left IFG plays an important role in sound learning and indicate that individual differences in learning aptitude stem from differences in the neuronal efficiency with which non-native sounds are processed.
  • Azar, Z., Backus, A., & Ozyurek, A. (2016). Pragmatic relativity: Gender and context affect the use of personal pronouns in discourse differentially across languages. In A. Papafragou, D. Grodner, D. Mirman, & J. Trueswell (Eds.), Proceedings of the 38th Annual Meeting of the Cognitive Science Society (CogSci 2016) (pp. 1295-1300). Austin, TX: Cognitive Science Society.

    Abstract

    Speakers use differential referring expressions in pragmatically appropriate ways to produce coherent narratives. Languages, however, differ in a) whether REs as arguments can be dropped and b) whether personal pronouns encode gender. We examine two languages that differ from each other in these two aspects and ask whether the co-reference context and the gender encoding options affect the use of REs differentially. We elicited narratives from Dutch and Turkish speakers about two types of three-person events, one including people of the same and the other of mixed-gender. Speakers re-introduced referents into the discourse with fuller forms (NPs) and maintained them with reduced forms (overt or null pronoun). Turkish speakers used pronouns mainly to mark emphasis and only Dutch speakers used pronouns differentially across the two types of videos. We argue that linguistic possibilities available in languages tune speakers into taking different principles into account to produce pragmatically coherent narratives
  • Backus, A., Schoffelen, J.-M., Szebényi, S., Hanslmayr, S., & Doeller, C. (2016). Hippocampal-prefrontal theta oscillations support memory integration. Current Biology, 26, 450-457. doi:10.1016/j.cub.2015.12.048.

    Abstract

    Integration of separate memories forms the basis of inferential reasoning - an essential cognitive process that enables complex behavior. Considerable evidence suggests that both hippocampus and medial prefrontal cortex (mPFC) play a crucial role in memory integration. Although previous studies indicate that theta oscillations facilitate memory processes, the electrophysiological mechanisms underlying memory integration remain elusive. To bridge this gap, we recorded magnetoencephalography data while participants performed an inference task and employed novel source reconstruction techniques to estimate oscillatory signals from the hippocampus. We found that hippocampal theta power during encoding predicts subsequent memory integration. Moreover, we observed increased theta coherence between hippocampus and mPFC. Our results suggest that integrated memory representations arise through hippocampal theta oscillations, possibly reflecting dynamic switching between encoding and retrieval states, and facilitating communication with mPFC. These findings have important implications for our understanding of memory-based decision making and knowledge acquisition
  • Baranova, J., & Dingemanse, M. (2016). Reasons for requests. Discourse Studies, 18(6), 641-675. doi:10.1177/1461445616667154.

    Abstract

    Reasons play an important role in social interaction. We study reasons-giving in the context of request sequences in Russian. By contrasting request sequences with and without reasons, we are able to shed light on the interactional work people do when they provide reasons or ask for them. In a systematic collection of request sequences in everyday conversation (N = 158), we find reasons in a variety of sequential positions, showing the various points at which participants may orient to the need for a reason. Reasons may be left implicit (as in many minimal requests that are readily complied with), or they can be made explicit. Participants may make reasons explicit either as part of the initial formulation of a request or in an interactionally contingent way. Across sequential positions, we show that reasons for requests recurrently deal with three possible issues: (1) providing information when a request is underspecified, (2) managing relationships between the requester and requestee and (3) explicating ancillary actions implemented by a request. By spelling out information normally left to presuppositions and implicatures, reasons make requests more understandable and help participants to navigate the social landscape of asking assistance from others.
  • Barış Demiral, Ş., Gambi, C., Nieuwland, M. S., & Pickering, M. J. (2016). Neural correlates of verbal joint action: ERPs reveal common perception and action systems in a shared-Stroop task. Brain Research, 1649, 79-89. doi:10.1016/j.brainres.2016.08.025.

    Abstract

    Recent social-cognitive research suggests that the anticipation of co-actors' actions influences people's mental representations. However, the precise nature of such representations is still unclear. In this study we investigated verbal joint representations in a delayed Stroop paradigm, where each participant responded to one color after a short delay. Participants either performed the task as a single actor (single-action, Experiment 1), or they performed it together (joint-action, Experiment 2). We investigated effects of co-actors' actions on the ERP components associated with perceptual conflict (Go N2) and response selection (P3b). Compared to single-action, joint-action reduced the N2 amplitude congruency effect when participants had to respond (Go trials), indicating that representing a co-actor's utterance helped to dissociate action codes and attenuated perceptual conflict for the responding participant. Yet, on NoGo trials the centro-parietal P3 (P3b) component amplitude increased for joint-action, suggesting that participants mapped the stimuli onto the co-actor's upcoming response as if it were their own response. We conclude that people represent others' utterances similarly to the way they represent their own utterances, and that shared perception-action codes for self and others can sometimes reduce, rather than enhance, perceptual conflict.
  • Barthel, M., Sauppe, S., Levinson, S. C., & Meyer, A. S. (2016). The timing of utterance planning in task-oriented dialogue: Evidence from a novel list-completion paradigm. Frontiers in Psychology, 7: 1858. doi:10.3389/fpsyg.2016.01858.

    Abstract

    In conversation, interlocutors rarely leave long gaps between turns, suggesting that next speak- ers begin to plan their turns while listening to the previous speaker. The present experiment used analyses of speech onset latencies and eye-movements in a task-oriented dialogue paradigm to investigate when speakers start planning their response. Adult German participants heard a confederate describe sets of objects in utterances that either ended in a noun (e.g. Ich habe eine Tür und ein Fahrrad (‘I have a door and a bicycle’)) or a verb form (Ich habe eine Tür und ein Fahrrad besorgt (‘I have gotten a door and a bicycle’)), while the presence or absence of the final verb either was or was not predictable from the preceding sentence structure. In response, participants had to name any unnamed objects they could see in their own display in utterances such as Ich habe ein Ei (‘I have an egg’). The main question was when participants started to plan their response. The results are consistent with the view that speakers begin to plan their turn as soon as sufficient information is available to do so, irrespective of further incoming words.
  • Bastos, A. M., & Schoffelen, J.-M. (2016). A tutorial review of functional connectivity analysis methods and their interpretational pitfalls. Frontiers in Systems Neuroscience, 9: 175. doi:10.3389/fnsys.2015.00175.

    Abstract

    Oscillatory neuronal activity may provide a mechanism for dynamic network coordination. Rhythmic neuronal interactions can be quantified using multiple metrics, each with their own advantages and disadvantages. This tutorial will review and summarize current analysis methods used in the field of invasive and non-invasive electrophysiology to study the dynamic connections between neuronal populations. First, we review metrics for functional connectivity, including coherence, phase synchronization, phase-slope index, and Granger causality, with the specific aim to provide an intuition for how these metrics work, as well as their quantitative definition. Next, we highlight a number of interpretational caveats and common pitfalls that can arise when performing functional connectivity analysis, including the common reference problem, the signal to noise ratio problem, the volume conduction problem, the common input problem, and the sample size bias problem. These pitfalls will be illustrated by presenting a set of MATLAB-scripts, which can be executed by the reader to simulate each of these potential problems. We discuss how these issues can be addressed using current methods.
  • Bauer, B. (2016). [Review of the book Social variation and the Latin language by James N. Adams]. Folia Linguistica Historica, 37, 315-326. doi:10.1515/flih-2016-0010.

    Files private

    Request files
  • Bauer, B. (2016). The development of comparatives in Latin texts. In J. N. Adams, & N. Vincent (Eds.), Early and late Latin. Continuity or change? (pp. 313-339). Cambridge: Cambridge University Press.
  • Bavin, E. L., Prendergast, L. A., Kidd, E., Baker, E., & Dissanayake, C. (2016). Online processing of sentences containing noun modification in young children with high-functioning autism. International Journal of Language & Communication Disorders, 51(2), 137-147. doi:10.1111/1460-6984.12191.

    Abstract

    Background: There is variability in the language of children with autism, even those who are high functioning. However, little is known about how they process language structures in real time, including how they handle potential ambiguity, and whether they follow referential constraints. Previous research with older autism spectrum disorder (ASD) participants has shown that these individuals can use context to access rapidly the meaning of ambiguous words. The severity of autism has also been shown to influence the speed in which children with ASD access lexical information. Aims: To understand more about how children with ASD process language in real time (i.e., as it unfolds). The focus was the integration of information and use of referential constraints to identify a referent named in a sentence. Methods & Procedures: We used an eye-tracking task to compare performance between young, high-functioning children with autism (HFA) and children with typical development (TD). A large sample of 5–9-year-old children (mean age = 6;8 years), 48 with HFA and 56 with TD participated; all were attending mainstream schools. For each item participants were shown a display of four images that differed in two dimensions. Each sentence contained an adjective and noun that restricted the choice from four to two (the target and competitor), followed by a prepositional phrase (e.g., the blue square with dots); this added modifying information to provide a unique description of the target. We calculated looking time at the target, the competitor and the two distractors for each 200 ms time interval as children processed the sentence and looked at the display. Generalized estimating equations were used to carry out repeated-measures analyses on the proportion of looking time to target and competitor and time to fixate to target. Outcomes & Results: Children in both groups (HFA and TD) looked at the target and competitor more than at the distractors following the adjective and noun and following the modifying information in the prepositional phrase more at the target. However, the HFA group was significantly slower in both phases and looked proportionally less at the target. Across the sample, IQ and language did not affect the results; however, age and attention had an impact. The older children showed an advantage in processing the information as did the children with higher attention scores. Conclusions & Implications: The HFA group took longer than the TD group to integrate the disambiguating information provided in the course of processing a sentence and integrate it with the visual information, indicating that for the ASD group incremental processing was not as advanced as for children with ASD, and they were less sensitive to referential conventions. Training for young children with ASD on the use of referential conventions and available contextual clues may be of benefit to them in understanding the language they hear.
  • Bavin, E. L., Kidd, E., Prendergast, L. A., & Baker, E. K. (2016). Young Children with ASD Use Lexical and Referential Information During On-line Sentence Processing. Frontiers in Psychology, 7: 171. doi:10.3389/fpsyg.2016.00171.

    Abstract

    Research with adults and older children indicates that verb biases are strong influences on listeners’ interpretations when processing sentences, but they can be overruled. In this paper, we ask two questions: (i) are children with Autism Spectrum Disorder (ASD) who are high functioning sensitive to verb biases like their same age typically developing peers?, and (ii) do young children with ASD and young children with typical development (TD) override strong verb biases to consider alternative interpretations of ambiguous sentences? Participants were aged 5–9 years (mean age 6.65 years): children with ASD who were high functioning and children with TD. In task 1, biasing and neutral verbs were included (e.g., eat cake versus move cake). In task 2, the focus was on whether the prepositional phrase occurring with an instrument biasing verb (e.g., ‘Chop the tree with the axe’) was interpreted as an instrument even if the named item was an implausible instrument (e.g., candle in ‘Cut the cake with the candle’). Overall, the results showed similarities between groups but the ASD group was generally slower. In task 1, both groups looked at the named object faster in the biasing than the non-biasing condition, and in the biasing condition the ASD group looked away from the target more quickly than the TD group. In task 2, both groups identified the target in the prepositional phrase. They were more likely to override the verb instrument bias and consider the alternative (modification) interpretation in the implausible condition (e.g., looking at the picture of a cake with a candle on it’). Our findings indicate that children of age 5 years and above can use context to override verb biases. Additionally, an important component of the sentence processing mechanism is largely intact for young children with ASD who are high functioning. Like children with TD, they draw on verb semantics and plausibility in integrating information. However, they are likely to be slower in processing the language they hear. Based on previous findings of associations between processing speed and cognitive functioning, the implication is that their understanding will be negatively affected, as will their academic outcomes.
  • Becker, M., Guadalupe, T., Franke, B., Hibar, D. P., Renteria, M. E., Stein, J. L., Thompson, P. M., Francks, C., Vernes, S. C., & Fisher, S. E. (2016). Early developmental gene enhancers affect subcortical volumes in the adult human brain. Human Brain Mapping, 37(5), 1788-1800. doi:10.1002/hbm.23136.

    Abstract

    Genome-wide association screens aim to identify common genetic variants contributing to the phenotypic variability of complex traits, such as human height or brain morphology. The identified genetic variants are mostly within noncoding genomic regions and the biology of the genotype–phenotype association typically remains unclear. In this article, we propose a complementary targeted strategy to reveal the genetic underpinnings of variability in subcortical brain volumes, by specifically selecting genomic loci that are experimentally validated forebrain enhancers, active in early embryonic development. We hypothesized that genetic variation within these enhancers may affect the development and ultimately the structure of subcortical brain regions in adults. We tested whether variants in forebrain enhancer regions showed an overall enrichment of association with volumetric variation in subcortical structures of >13,000 healthy adults. We observed significant enrichment of genomic loci that affect the volume of the hippocampus within forebrain enhancers (empirical P = 0.0015), a finding which robustly passed the adjusted threshold for testing of multiple brain phenotypes (cutoff of P < 0.0083 at an alpha of 0.05). In analyses of individual single nucleotide polymorphisms (SNPs), we identified an association upstream of the ID2 gene with rs7588305 and variation in hippocampal volume. This SNP-based association survived multiple-testing correction for the number of SNPs analyzed but not for the number of subcortical structures. Targeting known regulatory regions offers a way to understand the underlying biology that connects genotypes to phenotypes, particularly in the context of neuroimaging genetics. This biology-driven approach generates testable hypotheses regarding the functional biology of identified associations.

Share this page