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Seminar on Neurolinguistics
Sprogvidenskabelig Forskerskole Nord (SFN).
April 20-21, 2005
Department of English
Institute of Language, Literature & Culture,
University of Aarhus
Building 467, Room 415 (4th floor)
Jens Chr. Skous Vej 7, DK-8000 Aarhus C
Program:
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Wednesday, April 20 | ||
10:00-11:30 |
Douglas Saddy
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11:45-12:45 |
Andreas Roepstorff
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12:45-13:45 |
Lunch |
13:45-15:15 |
Susan Bookheimer
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Organization of language in the inferior frontal gyrus: |
15:30-16:30 |
Kamila Ewa Sip
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Lie Performance vs. Lie Detection: |
16:45-17:45 |
Christian Gerlach
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19:00 |
Dinner |
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Thursday, April 21 | ||
10:00-11:30 |
Yosef Grodzinsky
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11:45-12:45 |
Ken Ramshøj Christensen
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12:45-13:45 |
Lunch |
13:45-15:15 |
Uta Noppeney
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Imaging the semantic system: The organisation of semantic memory |
15:30-16:30 |
Mikkel Wallentin
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See what I mean? Brain imaging of linguistic processing |
16:30 |
Exit |
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[Printer friendly .pdf version]
Organizers:
Ken Ramshøj Christensen,
Kamila Ewa Sip, and
Mikkel Wallentin.
Financed by Sprogvidenskabelig Forskerskole Nord (SFN).
Registration:
The seminar is open to everyone who is interested.
If you are planning to attend, it would be helpful to us to know about it,
so please send an email to Ken Ramshøj Christensen
(engkrc@hum.au.dk)
Abstracts:
Douglas Saddy
(Patholinguistics group,
Dept. of Linguistics, University of Potsdam)
Finding Meaning in the Brain
Cognitive Neuroscience has made considerable progress in identifying cortical processes associated with the processing of information. However, finding cortical markers associated with the ‘meaning’ or content embedded in these processes has proved very elusive. In this talk I will ask what do we mean by ‘meaning’ and survey some ERP and other neuroimaging results that attempt to identify cortical phenomena that covary with content rather than form. The nature of these investigations leads us to consider qualitative properties of cortical signals in addition to their quantitative aspect. Time permitting, we will also consider how human sensitivity to qualitative properties of a signal intersects with our sensitivity to its statistical properties.
Andreas Roepstorff
(Center for Functionally Integrative Neuroscience CFIN, University of Aarhus)
Communication as top-top interaction
Cognitive neuroimaging studies of language function have revealed intriguing interactions between systematic patterns of linguistic processing and systematic patterns of brain activity. However, i will argue that in order to understand what communication is doing to the brain, one may have to rethink the nature of cognitive experiments. I will propose that a conceptual shift from 'stimulus-response' experiments to 'script-report' experiments may provide such avenue. In the second part of my talk, I will explore how an understanding of communication as script exchange may be compatible with current hierarchical predictive coding models of brain function.
Susan Bookheimer
(Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles)
Organization of language in the inferior frontal gyrus: Contributions from functional imaging
This talk will review recent imaging studies of language that focus on the inferior frontal gyrus. Tradition views of language organization based on lesion-deficit models attribute the variety of language deficits associated with Broca’s aphasia to a lesion in Brodmann’s area 44 of the inferior frontal gyrus. More recent studies using voxel-based morphometry and other techniques on MRI images indicate that the complete syndrome of Broca’s area requires a lesion in the anterior insula including the underlying white matter. I will argue that Broca’s area is not a single brain region, but rather is composed of multiple, small focal regions in different parts of the IFG that each contribute uniquely to some aspects of language, including syntax, phonology, semantic integration, motor sequencing, response initiation and articulation at minimum. Most of these regions have primary functions that easily give rise to language processing but are not necessarily language-specific. It is argued that traditional large-modular approaches to understanding the neural organization of language are inaccurate; rather, small, highly interactive modules within the frontal lobe network underlie the range of functions performed by “Broca’s area”.
Kamila Ewa Sip
(Dept. of Linguistics, University of Aarhus)
Lie Performance vs. Lie Detection: A Neuropragmatic Approach to Interpersonal Deception.
I am going to present two aspects of my Ph.D. project: a behavioral study within the framework of pragmatics, and a brain imaging study. The preliminary examination will be based on the empirical analysis of the verbal and non-verbal performances while lying. To investigate human brain activation while deceiving, I plan to conduct multi-level fMRI experiments.
The presentation has two main aims. First I would like to elaborate on the notion of deception within a framework of interpersonal pragmatics. I am going to briefly discuss selected aspects of deceptive messages and their non-verbal correlates. The contextual variables ascribed to interactive communicative situations need to be considered as the analytical prisms. Second I will present my experimental paradigms for both the empirical and neuroimaging investigations of deception. Recent fMRI studies of deception (e.g. Spence et.al. 2001 or Ganis et.al 2003) have shown that deception is a very complex and intricate mental activity that triggers different brain areas in accordance with specific mental tasks. The wide spectrum of cerebral activation is considered to be the result of human capacity to be creative in the process of conducting complicated language/information transfers.
The presentation will cover issues such as: deception as social process, lie detection, pragmatics and deception, advantages and disadvantages of laboratory experiments, and schema of the planned experiments within my project.
References:
Ganis, G. et.al. (2003) Neural Correlates of Different Types of Deception: an fMRI Investigation. Cerebral Cortex 13.8: 830-836.
Spence, S. A. et.al. (2001) Behavioral and Functional Anatomical Correlates of Deception in Humans. NeuroReport 12.13: 284-2853.
Christian Gerlach
(Learning Lab Denmark, The Danish University of Education)
Category-specificity: It’s not all about semantics
Some of the more intriguing disorders following brain damage are the so-called category-specific disorders (CSDs) where patients are able to recognize or comprehend some categories of objects (e.g. , artefacts) but not others (e.g., natural objects). Despite intense study over the last 20 years there is still not agreement about the probable causes of these disorders. One likely reason for this state of affairs is that the CSDs can seemingly occur for a variety of reasons. Some CSDs appear to reflect processing differences between categories at a lexical level whereas others seem to reflect differences at a semantic level. Perhaps the best understood CSDs arise as a consequence of damage to pre-semantic levels in visual object processing. I will argue that these CSDs reflect processing differences between categories that also exist in normal subjects but which become exacerbated following brain damage. This proposition implies that category effects can also be experimentally revealed in normal subjects which indeed is the case. Based on a series of experiments we have conducted over the last seven years, I will advance a general theory of category-specificity at pre-semantic stages in visual object processing. This theory can account for the majority of category effects reported with normal subjects and it can also explain why damage to visual areas may result in both CSDs for artefacts and CSDs for natural objects. If time permits, I will end my talk with some speculations regarding what this says about the functional organization of knowledge in general.
Yosef Grodzinsky
(Department of Psychology, Tel Aviv University and
Department of Linguistics,
Neurology/Neurosurgery, McGill University, Montréal)
A Blueprint for a Brain Map of Syntax
As we listen casually to sentences during conversation or while we watch TV, our brains carry out highly complex computations on the incoming signal. Central among these is high-speed syntactic analysis which we do rather effortlessly. Linguists study the nature of these computations; neurolinguists investigate their neural implementation. How language mechanisms might be organized in the brain, what counts as relevant evidence, and how it is adduced, and what its implications are will be the topic of this talk. It will be about what we know about the organization of syntax in the brain, and how we came to know it.
I will start with a quick tutorial for the uninitiated, and present some theoretical considerations that motivate certain syntactic principles. I will then present evidence regarding their neurological instantiation. Among these will be (i) syntactic movement (a k a grammatical transformations: the dancer picked the purple rose => which rose did the dancer pick), and (ii) principles that regulate the way certain referentially dependent elements fix their reference in a sentence (a k a binding, as in the dancer looked at herself in the mirror). I will discuss recent studies of these rule systems in healthy adults, carried out through fMRI tests of receptive syntax, and show two things: first, different applications of syntactic movement (e.g., questions, topicalization) activate similar cerebral loci (mostly in the left inferior frontal gyrus [Broca's region], and in both temporal lobes [Wernicke's region]); second, binding relations (as above) surprisingly activate areas in the frontal lobe of the right cerebral hemisphere.
Letting the audience catch their breath, I will then move to the second part of the talk, where these results will be juxtaposed to lesion data from behavioral and anatomical investigations of Broca's aphasic patients (usually subsequent to left-hemispheric stroke). When looked at superficially, the picture that arises from comprehension studies in aphasia is not pretty: it presents seemingly unruly, sometimes strange, patterns; further puzzles appear when cross-linguistic differences are thrown into the pot (e.g., aberrant comprehension performances of aphasic speakers of German/Dutch vs. Spanish, Chinese vs. English, or Italian vs. Hebrew). I will propose solutions to some of these puzzles, and try to justify a unified account, that suggests high regularity in impairment patterns in aphasia, and that also extends to available fMRI results from sentence processing experiments.
Finally, I will try to convince the audience that this relatively rich array of results has implications to (at least) three research domains: Linguistically, syntactic modularity will be shown to have neurological reflexes, which should lead us – or so I would suggest – to new ideas about the relevance of neurology to linguistic theory; Cognitively, the fact that both movement and binding are dependency relations that tax working memory, but are localized in distinct cerebral loci, should lead to a more refined view of the part of working memory thought to reside in, perhaps around, Broca’s region; neurologically, these results might lead to a fairly radical revision of our beliefs about the way language is localized in cortex.
Relevant reading (available in http://freud.tau.ac.il/~yosef1):
Grodzinsky, Yosef. 2000. The Neurology of Syntax:
Language Use without Broca’s Area. Behavioral and Brain Sciences, 23.1., 1-71.
Grodzinsky, Yosef. In press. "A Blueprint
for a Brain Map of Syntax." In Grodzinsky, Y. and K. Amunts, eds., Broca’s Region.
New York: Oxford University Press.
Ken Ramshøj Christensen
(Dept. of English, University of Aarhus, The MR Research Centre, Aarhus)
Operators, Domains, and the Role of Broca's Area
Studies of language deficits as well as neuroimaging studies indicate that syntactic processing of displaced constituents is implemented in the brain as a distributed network of modules. I present data from an fMRI study on Danish operator movement which offers further support for such a distributed syntactic network. I shall argue that the notion of working memory (WM), at least when it comes to language processing, must be constrained by linguistic theory; the distributed network, I argue, reflects computation of different syntactic domains.
Uta Noppeney
(Wellcome Department of Imaging Neuroscience, University College London)
Imaging the semantic system: The organisation of semantic memory
How is semantic information, our knowledge about the world, represented, processed and retrieved by the human brain? In this talk, I will present a series of functional imaging studies that investigate the neural systems sustaining these processes.
First, we characterize a fronto-temporal semantic executive system that is activated irrespective of stimulus modality or semantic content. These activations were modulated by executive task demands or stimulus-response association strength (e.g. due to semantic interference) suggesting that frontal as well as temporal regions are engaged in retrieving and selecting semantic information from memory.
Second, we investigate the neural systems that respond selectively to different semantic contents or categories. Selective semantic deficits in neuropsychological patients have suggested distinct neural systems for processing items from different semantic categories. In particular, a distinction has been drawn along the dimensions (A) animate vs. inanimate and (B) abstract vs. concrete.
A) In a series of functional imaging studies, we presented subjects with semantic stimuli whilst manipulating (1) semantic content (e.g. tools vs. animals), (2) stimulus modality (e.g. pictures vs. words) and (3) task (e.g. explicit vs. implicit). This multi-factorial approach allowed us to identify regions that responded selectively to a particular type of semantics. Using effective connectivity analyses (Dynamic Causal Modelling), we dissociated two distinct mechanisms that engender category-selectivity: (1) a ventral object recognition system showing modality-dependent tool-selective effects mediated by bottom up effects; (2) a dorsal visuo-motor system showing task-dependent tool-effects mediated by increased top-down influences of task-related prefrontal activity. In a further study, early blindness was used as a lesion model to investigate whether the organisation of the semantic system is altered by perturbations of early visual experience.
B) In addition to semantic concepts that refer to objects in the external world, humans can also form abstract concepts. Previous behavioural research has highlighted the importance of sentences for specifying the meaning of abstract concepts. Intriguingly, our results implicate a left fronto-temporal system extending into the temporal pole in both, processing of abstract concepts and sentence processing.
Mikkel Wallentin
(Center for Functionally Integrative Neuroscience CFIN, University of Aarhus)
See what I mean? Brain imaging of linguistic processing and spatial cognition. Is there an overlap?
How does a mental representation arise from linguistic input? And how does mental representation arise from perceptual input? Are perception and conception separate phenomena? Cognitive linguists, such as Leonard Talmy, claim the necessity for a more or less common system of "ception". Both research from neuroscience and linguistics have suggested that brain regions involved in the processing of spatial relations, such as medial temporal cortex (hippocampus & parahippocampal gyrus), posterior middle temporal regions (LPMT) and medial parietal regions (precuneus), might be good candidates for handling meaning construction in whole sentence processing. In this talk I briefly present evidence indicating that these brain regions are involved in spatial processing, and then go on to present results from our recent fMRI experiments using linguistic stimuli.
Last updated April 19, 2005
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