Presentations

Abstract

Das wichtigste und zugleich komplexeste Organ im menschlichen Körper ist das Gehirn.
Es ist beteiligt an allem, was uns lieb und teuer ist. Ohne Gehirn kein Gedächtnis, kein Gefühl, keine Sprache oder Wahrnehmung, so Dr. Peter Hagoort, Professor am Donders Centre for Cognition an der Radboud Universität. Der Nimweger Wissenschaftler beschäftigt sich mit den revolutionären Entwicklungen auf dem Gebiet der Scanbildtechnologie.

Abstract

Human face-to-face communication is a multi-modal activity. Recent research has shown that, during comprehension, recipients integrate information from speech with that contained in co-speech gestures (e.g., Kelly et al., 2010). The current studies take this research one step further by investigating the influence of another modality, namely eye gaze, on speech and gesture comprehension, to advance our understanding of language processing in more situated contexts. In spite of the large body of literature on processing of eye gaze, very few studies have investigated its processing in the context of communication (but see, e.g., Staudte & Crocker, 2011 for an exception). In two studies we simulated a triadic communication context in which a speaker alternated their gaze between our participant and another (alleged) participant. Participants thus viewed speech-only or speech + gesture utterances either in the role of addressee (direct gaze) or in the role of unaddressed recipient (averted gaze). In Study 1, participants (N = 32) viewed video-clips of a speaker producing speech-only (e.g. “she trained the horse”) or speech+gesture utterances conveying complementary information (e.g. “she trained the horse”+WHIPPING gesture). Participants were asked to judge whether a word displayed on screen after each video-clip matched what the speaker said or not. In half of the cases, the word matched a previously uttered word, requiring a “yes” answer. In all other cases, the word matched the meaning of the gesture the actor had performed, thus requiring a ‘no’ answer.

Abstract

During reading, people not only retrieve meaning from individual words, they also combine words into multi-word meaning representation and derive inference from it. In single word studies, action verb meaning (kick) is understood through the activation of motor areas, typically interpreted as showing the necessity of these sensori motor regions as part of a semantic circuit for language comprehension (Pulvermüller & Fadiga, 2010). But it remains unclear how this association-based theory scales up to understanding sentence meaning and how the semantic circuit subserves inference
making at the sentence level.

Abstract

Words’ meanings vary with context. When do context effects arise? The answer to this is critical for deciding between theories assuming that meanings are accessed from a stable mental lexicon and theories that suggest meanings are constructed ad hoc. On the first view, a word form activates an invariant semantic representation, which is subsequently tailored to fit the context (e.g., Evans, 2009; Machery, 2010). On an alternative view, word forms are cues to construct meaning; the information that gets activated is always co-determined by the word and its context (Elman, 2004; 2009; Lai, Hagoort, & Casasanto, 2011).

Abstract

An important property of language is that it can be used exophorically, for instance in referring to entities in the extra-linguistic context of a conversation using demonstratives such as “this” and “that”. Despite large-scale cross-linguistic descriptions of demonstrative systems, the mechanisms underlying the comprehension of such referential acts are poorly understood. Therefore, we investigated the neural mechanisms underlying demonstrative comprehension in situated contexts. Twenty-three participants were presented on a computer screen with pictures containing a speaker and two similar objects. One of the objects was close to the speaker, whereas the other was either distal from the speaker but optically close to the participant (“sagittal orientation”), or distal from both (“lateral orientation”). The speaker pointed to one object, and participants heard sentences spoken by the speaker containing a proximal (“this”) or distal (“that”) demonstrative, and a correct or incorrect noun-label (i.e., a semantic violation). EEG was recorded continuously and time-locked to the onset of demonstratives and nouns. Semantic violations on the noun-label yielded a significant, wide-spread N400 effect, regardless of the objects’ orientation. Comparing the comprehension of proximal to distal demonstratives in the sagittal orientation yielded a similar N400 effect, both for the close and the far referent. Interestingly, no demonstrative effect was found when objects were oriented laterally. Our findings suggest a similar time-course for demonstrative and noun-label processing. However, the comprehension of demonstratives depends on the spatial orientation of potential referents, whereas noun-label comprehension does not. These findings reveal new insights about the mechanisms underlying everyday demonstrative comprehension.

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.).