Presentations

Abstract

One of the most daunting tasks of a listener is to map a continuous auditory stream onto known speech sound categories and lexical items. A major issue with this mapping problem is the variability in the acoustic realizations of sound categories, both within and across speakers. Past research has suggested listeners may use various sources of information, such as lexical knowledge or visual cues (e.g., lip-reading) to recalibrate these speech categories to the current speaker. Previous studies have focused on audiovisual recalibration of consonant categories. The present study explores whether vowel categorization, which is known to show less sharply defined category boundaries, also benefit from visual cues.
Participants were exposed to videos of a speaker pronouncing one out of two vowels (Dutch vowels /e/ and /ø/), paired with audio that was ambiguous between the two vowels. The most ambiguous vowel token was determined on an individual basis by a categorization task at the beginning of the experiment. In one group of participants, this auditory token was paired with a video of an /e/ articulation, in the other group with an /ø/ video. After exposure to these videos, it was found in an audio-only categorization task that participants had adapted their categorization behavior as a function of the video exposure. The group that was exposed to /e/ videos showed a reduction of /ø/ classifications, suggesting they had recalibrated their vowel categories based on the available visual information. These results show that listeners indeed use visual information to recalibrate vowel categories, which is in line with previous work on audiovisual recalibration in consonant categories, and lexically-guided recalibration in both vowels and consonants.
In addition, a secondary aim of the current study was to explore individual variability in audiovisual recalibration. Phoneme categories vary not only in terms of boundary location, but also in terms of boundary sharpness, or how strictly categories are distinguished. The present study explores whether this sharpness is associated with the amount of audiovisual recalibration. The results tentatively support that a fuzzy boundary is associated with stronger recalibration, suggesting that listeners’ category sharpness may be related to the weight they assign to visual information in audiovisual speech perception. If listeners with fuzzy boundaries assign more weight to visual cues, given that vowel categories have less sharp boundaries than consonants, there ought to be audiovisual recalibration for vowels as well. This is exactly what was found in the current study.

Abstract

The classroom is designed to teach children cultural inventions for which the brain is not evolutionary designed. Hence the
classroom environment has to implement cultural reycling of neuronal maps. To do this effectively it has to recruit existing neural
infrastructure. Therefore, teaching programmes have to be tailored to the possibilities and limitations of available neural architecture.
An example in case is reading, a cultural invention of a few thousand years old. Orthographies and reading methods need
to use visual cortex areas in the most optimal way. I will discuss how the characteristics of different orthographies are tailored
to the possibilities of complex cells in visual cortex. In addition, different reading methods will be evaluated in the light of our
understanding of human brain organization. I will argue that a systematic investigation of culture-brain relations is much needed
for optimizing the optimal environment.

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.).