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THE DATA OF CONSCIOUSNESS. JG Taylor Department of Mathematics, King’s College, Strand, London Email: john.g.taylor@kcl.ac.uk . NATURE OF THE DATA ON CONSCIOUSNESS. Subjective (inner: ontological) & Objective (3 rd person: epistemological) New insights arising from:
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THE DATA OF CONSCIOUSNESS JG Taylor Department of Mathematics, King’s College, Strand, London Email: john.g.taylor@kcl.ac.uk
NATURE OF THE DATAON CONSCIOUSNESS • Subjective (inner: ontological) & Objective (3rd person: epistemological) • New insights arising from: 1) Phenomenology (deeper view of self) 2) Diseases of the self 3) Cognitive neuroscience (brain imaging/attention) • Use data from all three strands
Consciousness Defined? • ‘Consciousness of’ = Intentionality (content) • ‘Consciousness’ (with no content: inner self) • Features of consciousness (dynamics/ transparency/ closeness/unity/ ’what it is like’/ intentionality/intentionality of actions/ …) • ‘bridging identifications’: brain → mental states • NCC: need understanding of what searched for!
CONTENTS • Phenomenology of the Self (inner v outer) • Diseases of the Self (supports inner) • Body & Self (support of inner) • Cognitive Science: Attention • Conclusions: The Problems to be Faced
1. PHENOMENOLOGY OF THE SELF • NO ‘INNER SELF’ IN MAINSTREAM COGNITIVE SCIENCE (Rejected by Hume, Western Cognitive science) • ‘NAÏVE’ EXLORATIONS OF SELF ‘GAPPY’ NATURE OF AWARENESS: INNER ↔ OUTER (G Strawson, JCS 2000) • RECOGNISED IN EASTERN THOUGHT (‘beads on a string’) • FROM WESTERN PHENOMENOLOGY (Husserl, Sartre, Merlau-Ponty, Franck, Zahavi, Parnas, …)
‘I’: Object or Subject? • If: Awareness = relation of subject (experiencer) with object (experienced) • Then ‘I’ must refer to its object • I ≠ proper name or noun • I ≠ the person with any set of properties • Eg Oedipus did not know it was he* when he sought for ‘the person who brought trouble to Thebes’ • So to what does ‘I’ refer?
Nature of ‘I’ From Phenomenology • ‘INNER SELF’: • * Immune to error • (I am certain I am in pain – you cannot ask: Are you sure it is you in pain? Wittgenstein) • * Not self-reflection: pre-reflective • (Cannot have consciousness perceiving itself without infinite regress: needs knowledge that is self, from higher order, & so on: Shoemaker’s Explanatory Gap: HOP/HOT theories will not do: Frank; Zahavi) → • * Gives sense of ‘what it is like to be’ (Nagel) • DEBATE OVER ‘EGOLESS’ INTERNAL SELF: PRE-REFLECTIVE SELF v OUTER WORLD * The ‘hard problem’ (Chalmers) • AT LEAST 2 PARTS TO CONSCIOUSNESS: * Purely intrinsic, non-relational, Pre-Reflective Self (PRS) * Relational, contentful consciousness of External World
Self by Reflection? • Act of reflection on perception • A conscious of B as identical to A • A→ B (perception, P) → A (reflection, R) • But R on P no self-awareness • Needs further act R’ to become self-aware • Leads to infinite regress • Or have intrinsic self-awareness (prior assumption, so not proved)
Conclusions: Basic Problem • Two parts to Consciousness: PRS + Content • How to ‘Mind the Gap’: PRS v Content? • No explanation from Western phenomenology • Cognitive science: no problem (no PRS) • But: *Hard problem *Explanatory Gap *Immunity to Error *No HOT approach • Look for help in mental diseases
2. Diseases of The Self • SCHIZOPHRENIA BASIC: “The libido of the schizophrenic withdraws from the outer world onto its own ego” (Freud) “His personal inner drive does not seek to identify with reality, but becomes like an empty slate.” (Minkowski, 1927: loss of connection to the world) “In truth, I am closer to the soul, to Dante’s Paradise, in that world, but I feel removed from life, devoid of emotion and detached from everything” (Elena, a schizophrenic patient of Morselli, 1930) “Uncertainty of selfhood: representations of things are not definitively experienced as ‘my’ representations” (Kimura Bin, 2002: loss of ‘I’ness of self) “I am somehow strange to myself – I am not myself” (Anne, schizophrenic patient of Blankenburg, 1991: loss of natural self-evidence )
Accounts of Schizophrenia “Such hyperattention dysfunction might represent the primary cognitive abnormality seen in schizophrenia” (Sarter & Bruno, 1999) “The patient does not feel being fully existing or alive, fully awake or alert, or fully present and affected” (Parnas, 2000) • ALSO DAMAGES TO SELF AS OBJECT (damaged access/ representation/ output) • ALSO TO WHAT CAN ACCESS CONSCIOUSNESS (semantic level maps intrude onto sensory buffers)
Explanations of Psychiatrists • “Disorders of the self represent the experiential core clinical phenomena of schizophrenia” (Parnas & Sass, 2002) • 3 basic problems: • 1) Loss of common sense in world • 2) Anomalies of self-awareness • 3) Disorders of prereflective relations to others (Parnas, 2003)
Conclusions to Section 2 • Evidence from schizophrenia: change of ipseity/pre-reflective self (↑ or ↓) • Also loss of connectivity to other important processes: relation to world/other people • Gives support for the existence of PRS • How does the PRS arise from the brain? • How is the loss in schizophrenia explained?
3. BODY & SELF • Western phenomenology (Husserl/Merleau-Ponty/Zahavi): PRS arises from the BODY • Body = ‘Null point’ of experience (Husserl) • Claimed to arise from proprioceptive feedback (Merleau-Ponty, Gallagher, Cassam, et al) • But neuroscience: body feedback just another! • Vulnerable to ∞ regress argument since kinaesthetics/proprioception relational • For de-afferented: no apparent loss of ‘I’
Recent Claims (Gallagher, ‘03) • Proprioception – both somatic & ecological – is non-perspectival • Immune to error through misidentification • Transparent (use to identify held object, body peripherally ‘aware’) • Non-ego-centric • Gives non-relational body frame
Detailed claims • Three sorts of proprioceptive activity: 1) Sub-personal (non-conscious) 2) Aware, but not about body identity 3) Aware, & about body (conscious) • Second sort = implicit awareness = pre/non-reflective awareness of body (PRS) • Spatial aspect: “proprioception follows the contours of my body, but not from a perspective” (Gallagher, section 3)
Data: Standard model of motor control (Sabes , 2000) • Have sensorimotor feedback used in standard error-correction mode • No differentiation of kinaesthetic/ proprioceptive from other feedback, to solve tasks
Further Data • Bimodal fusion cells discovered (visual/ kinaesthetic) in monkey PUL, PMCX, PCX • “CNS integrates proprioceptive information with visual information about the position of a target limb” (Haggard, 2001) • Kinaesthesia not crucial to awareness of actions: “Our perception of our own actions cannot be based on sensory feedback from the moving limb itself, since such sensory reafference would inevitably be delayed relative to the actual movement” (Haggard & Magno, 1999) • Consistent with no special place for kinaesthesia
Deafferentation Effects • Have de-afferented & controls using the same control structures in this case • proprioception irrelevant to fast corrections of motor trajectories • More important is efference copy of motor command • Also motor control system has two levels: • Attended (controlled) v unattended (automatic)
Automatic v Controlled Responses • Experiments show two classes of motor response • Based on rapid automatic responses v slower controlled responses • Automatic responses, involving posterior parietal & cerebellar control systems (with inputs from all modalities, including proprioceptive feedback) • Attended responses run by parieto-frontal network of brain sites
Pointing PerformancePisella et al, Nature Nsci 2000 • Automatic movements < 240 msecs • Controlled movements > 240 msecs
Conclusions to Section 3 • Feedback used in all modalities: all grist to controlling brain! • Body feedback both in SI/SII, & by modulation of sensory inputs • Not expect difference observed in treatment of different feedbacks, nor of spatiality • Need analysis of attended movements for analysis of awareness of any feedback • Doubt body = PRS, still ∞ regress problem • Problem about motor awareness • Still to understand PRS Content: By Attention
4. ATTENTION • LONG HISTORY OF CONSIDERATION • AS COMPETITION: ‘Of two movements, the stronger always tends to extrude the latter’ (Aristotle) • AS DIRECTED ATTENTION: ‘attentive ears and mind’ (Lucretius, 1st century BC) • ATTENTION DIRECTED VOLUNTARILY OR NOT: ‘tug of attention’ v voluntary direction (Augustine, 354-430AD, then more fully by Descartes)
ATTENTION = SELECTION OF PART OF SCENE FOR ANALYSIS (acts as ‘filter’ on input) AMPLIFICATION OF ATTENDED + INHIBITION OF DISTRACTORS (in sensory & motor cortices, & higher sites) DETECT ATTENTION CONTROL SIGNAL IN NETWORK OF CORTICAL REGIONS
INCREASED ACTIVITY LEVEL WHEN ATTENTION DIRECTED TO SENSORY INPUT (from early EEG & PET studies, now fMRI, MEG, including increased -synchronisation for binding, and single cell studies) Modulation of V4 Cell Response (Maunsell et al, J NSci 19:431, 1999) FIG. 2. Data from one V4 cell showing enhanced responses in the attended mode (black) relative to the unattended mode (gray)
Paradigm for Motor Attention Study(Binkofski et al, J Neurophysiol 2002)
INCREASED ACTIVITY IN MOTOR CORTICAL SITES FOR ATTENTION TO RESPONSE, & IN HIGHER MOTOR SITES (Binkofski et al, J Neurophysiol 2003)
OVERALL: ATTENTION MOVEMENT INVOLVES BRAIN SITES WITH 2 DIFFERENT FUNCTIONS: AMPLIFY/DECREASE SENSORY INPUT (in sensory cortices) CREATE CONTROL SIGNALS FOR THIS (in parietal & frontal cortices): “Attention-related activity in frontal and parietal areas does not reflect attentional modulation of visually evoked responses, but rather the attentional operations themselves.” (Kastner & Ungerleider, Neuropsychologia, 39: 1263-1276, 2001) EXPECT SITES WITH SPECIFIC FUNCTIONS OF CONTROL (goals, monitors, feedback signals)
ORESTEIA Structure • Output: Advice to user (Medical state, if critical level; or future dangers needing increased user care) • How to fuse modalities to produce useful ORESTEIA agent (car-driving, etc)? • By attention control (From car environment - & driver’s physiology) • Overall architecture of ORESTEIA agent:
Consciousness Requires Attention • Neglect: Inability to direct attention focus (loss of parietal (TPJ/IPL) by stroke) • Attentional Blink: Loss of ability to move attention from T1 to T2 in RSVP stream (worst at 300msecs after T1) • Inattentional Blindness: Inability to detect unattended change in environment (but semantic brain activations) • “The further function of attention is to allow selected perceptual information a foothold in consciousness” (Shapiro et al TICS, ‘97) Must search in Attention for Consciousness
Conclusions on Attention • ATTENTION MOVEMENT = ‘ACTION’ • 2 SORTS OF ATTENTION AS CONTROL: sensory motor • VARIOUS CONTROL MODULES SUPPORTED BY DATA (attention control, goals, buffer/forward model, monitor) • ATTENTION NECESSARY FOR CONSCIOUSNESS • NEED TO EXPLORE ATTENTION FURTHER BY SIMULATION • TRY BY CODAM
5. CONCLUSIONS: THE PROBLEMS TO BE FACED • Accept existence of PRS (≠ Body awareness) • Search for creation of PRS inside attention • search for 2 signals as NCC • 1st of PRS – may be short latency • = N2pc (at 200 msecs)? • 2nd is of content arising in WM buffers • = P300 (at 350-500 msecs)? • Is there separate motor awareness? • Also how PRS Content? • CODAM possible model of interaction