Presentations

Abstract

Recent work suggests that monitoring in speech production may occur via domain-general mechanisms responsible for detecting response conflict. To test this hypothesis, we measured EEG as people engaged in both non-verbal (flanker) and verbal (tongue twisters) tasks designed to elicit response conflict and errors. In the flanker task, people pressed a button corresponding to whether a center arrow was facing left or right, and response conflict was induced with flanking arrows pointing in the same (congruent; >>>>>) or a different (incongruent >><>>) direction. In the tongue twister task, people read sequences of four nonwords three times in which rhymes alternated in an ABAB pattern while onset speech sounds alternated in an ABBA (tongue twister) or an ABAB (non-tongue twister) pattern (e.g., tif deev dif teev vs. tif teev dif deef). Results in the fl anker task showed standard markers of response conflict in the form of an increased N2 for incongruent relative to congruent trials as well as an error-related negativity (ERN) for incorrect trials. Behaviourally, more errors were elicited for tongue twisters relative to nontongue twister trials, and an ERN was observed on incorrect responses. Correlations between the magnitude of the N2 and ERN in the fl anker task with the magnitude of the ERN and error rates in the tongue twister task are consistent with a common underlying locus. Adaptation effects preceding and following erroneous trials in production are also presented. These results are consistent with response confl ict serving as a cue to monitoring in speech production.

Abstract

A central and influential idea among researchers of language is that our language faculty is organized according to the principle of strict compositionality, which implies that the meaning of an utterances is a function of the meaning of its parts and of the syntactic rules by which these parts are combined. The implication of this idea is that beyond word recognition, language interpretation takes place in a two-step fashion. First, the meaning of a sentence is computed. In a second step the sentence meaning is integrated with information from prior discourse, with world knowledge, with information about the speaker, and with semantic information from extralinguistic domains such as co-speech gestures or the visual world. FMRI results and results from recordings of event related brain potentials will be presented that are inconsistent with this classical model of language intepretation. Our data support a model in which knowledge about the context and the world, knowledge about concomitant information from other modalities, and knowledge about the speaker are brought to bear immediately, by the same fast-acting brain system that combines the meanings of individual words into a message-level representation. The Memory, Unification and Control (MUC) model provides a neurobiological plausible account of the underlying neural architecture. Resting state connectivity data, and results from Psycho-Physiological Interactions will be discussed, suggesting a division of labour between temporal and inferior frontal cortex. These results indicate that Broca’s area and adjacent cortex play an important role in semantic and syntactic unification operations. I will also discuss fMRI results that indicate the insufficiency of the Mirror Neuron Hypothesis to explain language understanding. Instead I will sketch a picture of language processing from an embrained perspective.

Abstract

From a functionalist perspective all that brain research is claimed to have told us is that language processing "happens somewhere north of the neck" (Jerry Fodor, 1999). I will argue why I disagree with this conclusion, for at least the following three reasons. First, one fundamental question in the language sciences is: what makes the human brain language-ready? Understanding the neural architecture that supports human language function is a crucial part of the explanandum. I will show some unique features of human perisylvian cortex based on data from Diffusion Tensor Imaging and resting state fMRI. The second argument is that even if one is only interested in the cognitive architecture of language comprehension and production, relevant evidence can be obtained from neurobiological data, both structural and functional. I will discuss the consequences of connectivity patterns in the brain for assumptions in processing models of language, and I will show fMRI data based on a repetition suppression paradigm that provide evidence for the claim that syntactic encoding and parsing are based on the same mechanism. Finally, I will argue that framing theories of sentence processing in a way that connects to other areas of cognitive neuroscience might be helpful in asking interesting and relevant new questions. I will illustrate this in the context of the Memory, Unification and Control (MUC) model of language.

Abstract

A central and influential idea among researchers of language is that our language faculty is organized according to the principle of strict compositionality, which implies that the meaning of an utterances is a function of the meaning of its parts and of the syntactic rules by which these parts are combined. The implication of this idea is that beyond word recognition, language interpretation takes place in a two-step fashion. First, the meaning of a sentence is computed. In a second step the sentence meaning is integrated with information from prior discourse, with world knowledge, with information about the speaker, and with semantic information from extralinguistic domains such as co-speech gestures or the visual world. FMRI results and results from recordings of event related brain potentials will be presented that are inconsistent with this classical model of language intepretation. Our data support a model in which knowledge about the context and the world, knowledge about concomitant information from other modalities, and knowledge about the speaker are brought to bear immediately, by the same fast-acting brain system that combines the meanings of individual words into a message-level representation. The Memory, Unification and Control (MUC) model provides a neurobiological plausible account of the underlying neural architecture. Resting state connectivity data, and results from Psycho-Physiological Interactions will be discussed, suggesting a division of labour between temporal and inferior frontal cortex. These results indicate that Broca’s area and adjacent cortex play an important role in semantic and syntactic unification operations. I will also discuss fMRI results that indicate the insufficiency of the Mirror Neuron Hypothesis to explain language understanding. Instead I will sketch a picture of language processing from an embrained perspective.

Abstract

Traditionally, language comprehension has been studied as a solitary and unimodal activity. Here, we investigate language comprehension as a joint activity, i.e., in a dynamic social context involving multiple participants in different roles with different perspectives, while taking into account the multimodal nature of facetoface communication. We simulated a triadic communication context involving a speaker alternating her gaze between two different recipients, conveying information not only via speech but gesture as well. Participants thus viewed videorecorded speechonly or speech+gesture utterances referencing objects (e.g., “he likes the laptop”/+TYPING ON LAPTOPgesture) when being addressed (direct gaze) or unaddressed (averted gaze). The videoclips were followed by two object images (laptoptowel). Participants’ task was to choose the object that matched the speaker’s message (i.e., laptop). Unaddressed recipients responded significantly slower than addressees for speechonly utterances. However, perceiving the same speech accompanied by gestures sped them up to levels identical to that of addressees. Thus, when speech processing suffers due to being unaddressed, gestures become more prominent and boost comprehension of a speaker’s spoken message. Our findings illuminate how participants process multimodal language and how this process is influenced by eye gaze, an important social cue facilitating coordination in the joint activity of conversation.

Abstract

Although semantic influences on verbal short-term memory (STM) performance are well-established, substantially less research has studied the influence of syntactic representation. In the present study, syntactic and semantic factors were manipulated in order to explore how both interact to influence verbal STM. Subjects performed immediate, serial recall on lists of six Dutch words composed of three sets of adjective-noun pairs, where the nouns were either common (‘de’) or neuter (‘het’) gender. The grammaticality of the word pairs was manipulated through the morphological agreement between the adjectives and nouns (either legal of illegal), and the semantics by creating more or less meaningful word pairs (e.g., big bucket vs. grateful bucket). Syntactic and semantic factors were fully crossed within-subjects and within-items yielding a 2 (Grammatical) X 2 (Meaningful) X 2 (Noun Gender) design. Results on serial order memory accuracy revealed that both grammaticality and meaningfulness improved performance, and that the factors interacted, such that the beneficial effects of grammaticality were only present for lists of meaningful items. The present results thus demonstrate that while something as simple as morphological agreement (a long-term, syntactic constraint) can improve verbal STM performance, it only seem to do so in the presence stronger semantic constraints.

Abstract

Although semantic influences on verbal short-term memory (STM) are well-documented, substantially less research has examined influences of syntactic representation. In the present study, both syntactic and semantic factors were manipulated in order to explore how each affects verbal STM. Subjects (N=20) performed immediate, serial recall on lists of six Dutch words composed of three sets of adjective-noun pairs. Lists were factorially manipulated within a 2 (Noun Gender; common vs. neuter) X 2 (Grammatical; legal vs. illegal morphological agreement) X 2 (Meaningful; more vs. less) within-subjects design. Results on serial order memory revealed significant main effects of meaningfulness and grammaticality and a meaningfulness X grammaticality interaction, whereby the effects of the grammaticality were only present for more meaningful lists. The present results demonstrate that although syntactic factors can influence verbal STM, they only seem to do so in the presence stronger semantic constraints.

Abstract

One of the physiological markers of monitoring in both
speech and non-speech tasks is the so-called error related
negativity (ERN), an event-related potential that is
typically observed after error trials. However, the ERN is
also observed after correct trials in both manual and
verbal tasks, suggesting that it might be a more general
marker for the monitoring of response conflict. The
present work tests this hypothesis in speech production
by exploring a situation where increased response conflict
naturally occurs, namely, when multiple speech
outputs are simultaneously activated. Event-related
potentials were recorded while participants named
pictures in their first and second languages. Activation of
multiple outputs was manipulated through the form
similarity between translation equivalents (i.e., cognate
status). Replicating previous results, cognates were faster
to name than non-cognates. Interestingly, responselocked
analyses not only showed a reliable ERN on correct
trials, but that the amplitude of the ERN was larger
for cognates compared to non-cognates. Thus, despite
being faster to name, cognates seem to induce more
conflict during response monitoring. This in turn indicates
that the ERN is not simply sensitive to conflicting motor
responses, but also to more abstract conflict resulting
from co-activation of multiple phonological representations.

Abstract

My contribution will focus on the neural infrastructure for deriving speaker meaning. Recent accounts have argued that simulation (i.e. the re-enactment of states of perception and action) suffice to realize comprehension. This will fail on theoretical grounds. But I will also show empirical evidence indicating that the Theory of Mind network kicks in when articularized conversational implicatures are at stake. In addition, I will show that markers of Information Structure trigger the operation of a general attention network in the surface of modulating the depth of processing.

Abstract

A central and influential idea among researchers of language is that our language faculty is organized according to Fregean compositionality, which implies that the meaning of an utterances is a function of the meaning of its parts and of the syntactic rules by which these parts are combined. The implication of this idea is that beyond word recognition, language interpretation takes place in a two-step fashion. First, the meaning of a sentence is computed. In a second step the sentence meaning is integrated with information from prior discourse, with world knowledge, with information about the speaker, and with semantic information from extralinguistic domains such as co-speech gestures or the visual world. FMRI results and results from recordings of event related brain potentials will be presented that are inconsistent with this classical Fregean model of language intepretation. Our data support a model in which knowledge about the context and the world, knowledge about concomitant information from other modalities, and knowledge about the speaker are brought to bear immediately, by the same fast-acting brain system that combines the meanings of individual words into a message-level representation. The Memory, Unification and Control (MUC) model of language accounts for these data. Resting state connectivity data, and results from Psycho-Physiological Interactions will be discussed, suggesting a division of labour between temporal and inferior frontal cortex. These results indicate that Broca’s area and adjacent cortex play an important role in semantic and syntactic unification operations. I will also discuss fMRI results that indicate the insufficiency of the Mirror Neuron Hypothesis to explain language understanding. Instead I will sketch a picture of language processing from an embrained perspective.

Abstract

There is a school of philosophers who believe that the garden of nature should be cleaned first from the conceptual weeds by qualified philosophers, before empirical researchers should be allowed to enter the scene. I will defend a different position. This is one in which, for the case of cognitive neuroscience, knowledge on brain and cognition is strongly driven by new research tools and methods, which provide new challenges for conceptual analysis.

Abstract

With more than a hundred billion neurons, and more than 100.000 kilometers of connecting wires inside our skull, the human brain is the most complex organ in the known universe. Recent developments of brain imaging techniques, allow unprecedented previews of the human brain in action. What happens in our brain when we learn, when we change our opinion, when we speak, when we experience emotion; it will all be discussed in this lecture. How increased insights into brain function will impact society will be discussed as well.

Peter Hagoort is director of the Max Planck Instute for Psycholinguistics (since November 2006), and the founding director of the Donders Centre for Cognitive Neuroimaging (1999), a cognitive neuroscience research centre at the Radboud University Nijmegen, with participation of the Universities of Maastricht, Twente, and the Max Planck Institute for Psycholinguistics. In addition, he is professor in cognitive neuroscience at the Radboud University Nijmegen. His own research interests relate to the domain of the human language faculty and how it is instantiated in the brain. In his research he applies neuroimaging techniques such as ERP, MEG, PET and fMRI to investigate the language system and its impairments as in aphasia, dyslexia and autism. At the Donders Centre he is currently heading the research group Neurocognition of Language. At the Max Planck Institute he is heading a department on the Neurobiology of Language. For his scientific contributions, the Royal Netherlands Academy of Arts Sciences (KNAW) awarded him with the Hendrik Mullerprijs in 2003. In 2004 he was awarded by the Dutch Queen with the “Knighthood of the Dutch Lion.” In 2005 he received the NWO-Spinoza Prize. Peter Hagoort is fellow of the Royal Netherlands Academy of Arts and Sciences (KNAW).

Abstract

Connectivity among language-related brain regions during resting state has consistently been observed in previous studies. The current study investigates whether and how this connectivity is altered by a language task. Twenty-four native Dutch speakers were asked to read sentences for comprehension (i.e., a 50 min. language comprehension task), and resting state fMRI data were collected before and after the task. In accordance with previous similar work (Xiang, Fonteijn, Norris, & Hagoort. (2010). Topographical functional connectivity pattern in the perisylvian language networks. Cerebral Cortex, 20, 549-560.), ROIs in left BA44, BA45 and BA47 were used as seed regions. Functional connectivity (fc) of the seed regions with left parietal and temporal areas was found, in line with Xiang et al’s observations. Moreover, comparing fc's before and after the task, we found that the task altered fc patterns. After the task, for ROI BA44 and BA45, reduced connectivity with middle and posterior temporal regions as well as with the parietal lobule were found. In contrast, we 232 Cognitive Neuroscience Society — 2011 Annual Meeting Poster Session I — Tuesday, April 5, 3:00 - 5:00 pm, Pacific Concourse observed increased connectivity with medial frontal and superior frontal gyrus. For BA47, increased connectivity with anterior temporal lobe and bilateral precentral gyrus, and reduced connectivity with visual cortex were observed. Together the results suggest that language tasks modulate the resting-state connectivity within the brain's language network, in line with previous work (Waites, Stanislavsky, Abbott, & Jackson. (2005) Effect of prior cognitive state on resting state networks measured with functional connectivity. Human Brain Mapping, 24, 59-68.).