neurological disorders of embodied and multimodal communication

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Neurological disorders of embodied and multimodal

communicationElisabeth Ahlsén

Department of Linguistics & SSKKII Center for Cognitive Science, Göteborg University

ZiF Center for Interdisciplinary Research, Bielefeld University

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Contents• What types of models and frameworks are used in work

with communication disorders today and what are the main assumptions behind them?

• What are the present views of embodied communication like? - some frameworks and trends, models and findings

• What are the consequences of applying these views of communication to communication disorders? What can be questioned, changed/revised, replaced, removed or introduced?

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Frameworks for working with communication disorders today?

Some examples:- Classical serial production and perception models (still

very popular)- Classical structuralist systems of categories- Frameworks for aphasia classification (Boston, Luria)

To some extent also:- Cognitive linguistics (to some extent)- Conversation Analysis (to some extent)- Pragmatics: Speech act theory etc (to some extent)

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Assumptions, except for pragmatic/social part

• Serial production and perception processes in humans (e.g. Levelt 1989 model)(although many features of comm.disorders point to more integrated processing models as more adequate)

• ”Symbol manipulation” ideas, units such as inventories of phonemes and morphemes important

• More or less simplified localization models - (made better and worse by neuroimaging studies)

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Embodied communication - trends and ideas

- Alignment in communication (Pickering & Garrod)- Mirror neurons (Rizzolatti et al) (Arbib) (Gallese &

Lakoff) - extensions of this …- Coupling (Barresi)- Resonance, Entrainment, Contagion…- Importance of imitation and pantomime- Automatic processing- Evolutionary models revisited (Deacon)- Levels or degrees of conscious control

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Embodied communication - different aspects

The role of embodiment in communication and its importance for phylogenetic, as well as ontogenetic development, possibly also for microgenesis (i.e. the unfolding of a communicative contribution) and macrogenesis (i.e. conventionalization of communication in society) is attracting an increased interest. This interest is to some extent caused by hypotheses and findings concerning mirror neurons (cf Arbib, 2005. Gallese & Lakoff 2005).

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Arbib

Broca’s area developed atop mirror neuron system for graspingRole of imitation (simple, complex)Language - change from action-object frames to verb-argument structures(Cf. McNeilage: Frame-Content - speech directly)Link to cognitive grammar (construction grammar)Close relation aphasia-apraxia

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Gallese & LakoffConcepts are the elementary units of reason and linguistic meaning. They are conventional and relatively stable. As such, they must somehow be the result of neural activity in the brain. The questions are:Where? and How?

A common philosophical position is that all concepts—even concepts about action and perception—are symbolic and abstract, and therefore must be implemented outsidethe brain’s sensory-motor system.

We will propose that the sensory-motor system has the right kind of structure to characterise both sensory-motor and more abstract concepts. Central to this picture are the neural theory of language and the theory of cogs, according to which,

Brain structures in the sensory-motor regions are exploited to characterise the so-called “abstract”concepts that constitute the meanings of grammatical

constructions and general inference patterns.

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Pickering and Garrod

• Alignment - Routines - Imitation• Includes alignment of same person as speaker and listener• Priming basic

• Speech and gestures• Relation speech/language - praxis• What is more automatized - more controlled

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Feedback subproject - ZiF

• What is face-to-face communication like?

11Max Feedback + Max OutlookFeedback

Data analysis (ongoing)

L (00:00:13): Bist du im ersten Semester $R (00:00:15): Ich bin eigentlich im fünften Semester aber die ersten zwei hab ich

nicht wirklich was gemacht und dann // $L (00:00:18): aha $R (00:00:20): jetzt bin ich im dritten $L (00:00:23): Zoologie oder Botaniker oder was $R (00:00:26): entweder Anthro oder Zoologie das weiss ich noch nicht so genau $ L (00:00:28): aha die Anthropologen sind viel besser $L (00:00:33): mhm /// hast du schon den Seidler gemacht $R (00:00:35): ja $….

30 interacting pairs of students, systematically varied with respect to sex and mutual acquaintance Task to find out as much as possible about each other within 3 min Self-reported rapport

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A B

Control Access Decreasing

EVALUATION

APPRAISALEMOTION

MIRROR

KNOW-LEDGE

SELF-ADAPTA-TION

MIRROR

APPRAISALEMOTION

VOCAL–VISUAL-SYMBOLIC

VOCAL-VISUAL-DISPLAY

VOCAL-VISUAL-ANALOG

SELF-ADAPTA-TION

KNOW-LEDGE

EVALUATION

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Communication disorders

Time for reinterpretation:

Perception vs action not strictly posterior-anterior - more complex or in some respects more simple system

Concrete (iconic, indexical) vs abstract (symbolic) - more focus on relations?

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Examples of potential reinterpretations

Example 1) Area F4, F5 - Broca’s area: apraxia and aphasia - link?

Example 2) Area F4, F5 - apraxia and lack of ToM link?

Example 3) Broca’s area: anomia - concept forming disorder?

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Automatic and controlled processing in communication

- Mirroring - imitation - coactivation - alignment as central

- Interaction basic - same things activated in both speakers (close link motor-perc systems)

- Role of context, experience etc crucial- The whole picture - concrete vs abstract in

semantics (Gallese & Lakoff), grammar (Arbib)

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The example of Broca’s aphasia and apraxia

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Apraxia• ”Inability to perform voluntary/intended movements, with

(and without) tools, imitation?;

• either loss of idea of movement-inferior parietal area?, SMA, insula (SPGI- superior tip of the precentral gyrus of the insula)? - or of performance (motor programs) - premotor area”

• Ideational, Ideomotor/limb apraxia, Oral apraxia• Verbal apraxia/speech apraxia

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Apraxia of speech

Darley ”Apraxia of speech - 100 years of terminological confusion”

Relation to Broca’s aphasia?Often cooccur - close localization?Part of Broca’s aphasia?

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Broca’s aphasia and apraxia- are we still confused?

Still uncertainty about areas involved and their roles

Still uncertainty of basic function and basic disturbance

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Other relevant theories

• Motor theory of speech perception (Lieberman)

• Automatic vs ”propositional” speech and action (Jackson) - in more recent versions- difference in apraxia and Broca’s aphasia

…

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Questions

• So what can ideas and findings about embodiment add to better understanding?

• How should we integrate an analysis of gestures with reasonable conceptions of apraxias and Broca’s aphasia, other types of aphasia?

• What is the role of movements/actions? What is the role of verbs? Relation?

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Broca’s area - possible functionsBroca’s aphasia and apraxia often cooccur - normal case?

DissociationBasic disturbance of action-object frame -> also verb-

argument frame? Manual, oral and speech gestures? Imitation disturbed.

Quite automatized processing - production, perception through simulation?

”Propositional language” - sentences - Verbs?Broca’s area in complex semantic and syntactic processing -

LTM access?

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Combined frameworks - Deacon: • Associationism and Holism less of two alternatives than

two complementary aspects of a single process • Both only give description of movement or change of

information in cortical systems, since they fail to recognize this

• Reformulation - centrifugal and centripetal processes, cortically and cortex-subcortex - more general comprehensive model of brain function

• Based on recent neuroanatomical findings• Basic assumptions - higher-lower functions, forward-

backward direction, input-output will all need to be reexamined.

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Combined frameworksConnectionism:

Anterior cortex: backward connectionsPosterior cortex: forward connections

Microgenesis:Anterior and Posterior systems: in parallel from limbic to primary areas

Deacon: different cell layers, neurons project differently - centrifugal and centripetal laminar patterns

.

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Tiers - cortex: - Peripherally specialized areas (P)- Belt areas (B)- Association areas (A) centripetal centrifugal

- Limbic areas (L)Centripetal: Principal thalamic inputs to layers iii

and iv from the peripheral systemsCentrifugal: Cortical output from layers v and vi to

subcortical sitesCentrifugal: Limbic or intralaminar thalamic inputs

to layers i or vi

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An integrated perspective?