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Consciousness. What’s it all about?. Inattentional Blindness. Linking perception and attention What (if anything) do we perceive w/o attention? Mack & Rock (1998) Participants engaged in another task have an element added at one point
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Consciousness What’s it all about?
Inattentional Blindness • Linking perception and attention • What (if anything) do we perceive w/o attention? • Mack & Rock (1998) • Participants engaged in another task have an element added at one point • Example: judge which line is longer, but add a critical stimulus on a later trial. After critical trial participants are asked if they noticed anything unusual (very quick experiment) + +.
Change blindness • Outside world as an external memory to be probed by our senses (O’Regan) • Just like certain memories are not readily available unless ‘looked’ for, elements of the environment may not be perceived without attention • How would you check whether you were seeing all elements in a scene? • By attending to them
Although it seems as if we are perceiving the world as is, we are only getting info which is attended to • The refrigerator light is always on • Such findings from CB and IB suggest there is no conscious perception without attention • There is no sound from the tree falling, if no one is around to attend to it!
We have looked at the problem of how much info gets through, and know that even without conscious focusing of attention we do in fact perceive and are influenced by information in the environment • Recall Mackay and Sternberg studies • Shift focus • Of what are we aware?
Perception, Attention and Awareness are intimately related to one another • What does it mean to be aware of something? What is consciousness? • “Its meaning we know so long as no one asks us to define it” (James)
Consciousness • Broad definition: Awareness of both environmental and cognitive stimuli • Sensations, thoughts, memories etc. • Minds, Brains, and Consciousness • Brain: bunch of goo in our noggins • Mind: the sum of brain functioning of the brain, i.e. what the brain does • Consciousness: ?
The Problem of C • How can it be studied? Can it be? • What is its function/purpose? • Is it unitary? • What do we know? What do we not know?
Properties of Consciousness • James starts us off by giving four characteristics of consciousness • Subjective • “Every 'state' tends to be part of a personal consciousness.” • Changing • “Within each personal consciousness states are always changing.” • Continuous • “Each personal consciousness is sensibly continuous.” • Purposeful • “It is interested in some parts of its object to the exclusion of others, and welcomes or rejects -- chooses from among them, in a word -- all the while.”
Properties of Consciousness • Emergent • Like the liquidity of water or solidity of objects • Not a property that the parts of the system which create it possess, nor just the sum total of the parts • Irreducible? • Some (e.g. Searle) claim that the subjective nature of C leads to the distinction that it is not able to be reduced to the parts that cause it
Third-person data Wakefulness Perceptual discrimination Integrated control Access & self-monitoring Verbal Reports Focused attention Data re underlying brain processes“The easy problems” First-person data Visual experiences e.g. color, depth, … Other sensory experiences e.g. sound, taste, … Bodily sensations e.g. pain, orgasm, … Mental imagery e.g. recalled visual images, … Emotional experiences e.g. happiness, anger, … Stream of occurrent thought e.g. reflection, decision, … All are states of subjective experience: there is something it is like to have these states.The “hard problem”. The ‘hard’ problem of subjectivity
Example: Musical Processing • Third-person data • Sound wave patterns • Processes in auditory cortex • Behavioral reactions • Verbal reports (actual and potential) • First-person data • Musical experience • Related: qualia • Properties of objects related to the subjective experience of the object (the redness of red)
Hard Problem • What is it like to be a bat? • Nagel, Chalmers and other philosophers suggest in varying degrees that subjective experience is not reducible, and yet is necessary for a complete account of consciousness • However, does this keep us from even attempting to study Consciousness? • Can we construct a theory of C without including what it is like to have C?
The irreducibility of C • Considerations • Does your heart pump blood differently (in kind) than does mine? • Subjective experience is assumed to be at least correlated w/ brain functioning, if our brains are similar one would think our personal experiences are similar though colored by our own history (e.g. your ‘redness of red’ is similar to mine [similar eyes, visual cortices] but will call on different memories, emotions, thoughts etc.) • This would at least allow for the possibility of study/comparison/ generalization • Private experiences can be expressed publicly • Now a means for at least some inference is available, verbal report should have some correlation with subjective experience • So in a sense we do have indirect access to the personal from which insights might be gained • Much like electrons, planets in other solar systems etc., we can ‘observe’ the personal indirectly
The irreducibility of C • On the other hand.. • How well can we even know our private experience? • The psychological uncertainty principle • Observing the contents of consciousness necessarily change that experience • Subjective experience is unable to be verified • PUP • Verbal report wouldn’t be completely accurate (our own understanding of the workings of the mind can be incorrect) • No 1 to 1 mapping of verbal report to experience • So on the one hand we have (indirect) access to subjective experience but it is problematic • Suggestion: • Construct a theory of consciousness that will allow for evaluation and testable predictions (like we do with everything else in science)
Properties of Consciousness • Variable • States of C • Vs. UnC • Serial and limited capacity • We can only be conscious of one thing at a time (which we are attending to) • There are a great many things that we are not conscious of
Properties of Consciousness • Widespread Access • In spite of limitations, consciousness has access to wide variety of knowledge, skills and actions • Can influence activation of UnC content and even physiological functioning (biofeedback) • Constructive? • Are UnC states simply in waiting, biding their time until the ‘threshold’ of C is reached? • Or is C some sort of construction of pre-C structures to deal with the present environmental situation? • Activated schemas are not themselves C, but contribute to the C experience
Levels of Consciousness • Active, analytic consciousness on a continuum of degrees of consciousness • Focal awareness (the focus of attention) • Reflective • Primary • Peripheral awareness • accessible by a shift of attention • Unconsciousness • Subconscious (accessible to conscious awareness) • Nonconscious (not accessible)
Unconsciousness • Subconscious • Not in awareness • Not necessarily retrievable into awareness by will • Influences current processing • Nonconscious • Not in awareness • Not retrievable by will • Not necessarily influencing current processing • Perhaps better(?) distinction: C and Not-C
On the Relation between Conscious and Unconscious • Freud’s View • Active repression of unconscious • Conscious distortion • Cognitive View • Lack of activation, not active repression • No special distortion
Metaphors of Consciousness • Activation threshold • Novelty • Spotlight • Theater
Activation threshold • Activation of UnC content reaches threshold and becomes conscious • Problems • Redundancy effect: repeated and predictable stimulation can lead to UnC processing • Automaticity • Goes against idea of C as a construction
Novelty • Novelty • Change in the environment (dishabituation) • Disconfirmation of expectation (surprise) • Violation of skilled routines (interruptions in the flow of action • Consciousness functions to direct attention to maximize adaptation to novel and significant events • Like the activation threshold metaphor, does speak to a function of C, but doesn’t allow for a complete picture
Spotlight • Bringing things into focus (thoughts, objects in the environment), the selective nature of consciousness • Questions remain: • How is the focus determined? • Why this content and not others? • Once it is selected, what happens to the info? • Is there further processing (e.g. semantic), does it go to motor systems • What does it mean for content to be conscious?
Theater • Whatever is on the conscious stage is available to a large (UnC) audience • Various processes (e.g. executive:director) operate behind the scenes to control how consciousness plays out.
Functions of Consciousness • Choice and selection of action • Modification and evaluation of long-term plans • Adaptation to novel events • Retrieval from long term memory • Construction of storable representations of current activities and events • Reflective, Self-monitoring • Troubleshooting/error detection
Functions of Consciousness • Choice and selection of action • Can recruit subgoals to organize and carry out action to the attainment of a primary goal • Prioritizes, makes some info more accessible to consciousness • Executive function • Not an executive system but the executive system has access to it, and so UnC processes are affected • Modification and evaluation of long-term plans • Alternative actions considered and different outcomes evaluated
Functions of Consciousness • Adaptation to novel events • More novelty more conscious effort needed to process • Retrieval from long term memory • C not necessary for retrieval but can be used to retrieve information necessary to the situation • Construction of storable representations of current activities and events • Information stored and retrieved for future comparisons of present and past
Functions of Consciousness • Reflective, Self-monitoring • Through inner speech and imagery we can control C and UnC functioning • Troubleshooting/error detection • Conscious resources may be activated when other processes (often UnC) are interrupted or breakdown
Scientific Approaches to the Study of Consciousness • Consciousness as a variable: studies look at different types of stimulation (C vs. UnC), memory (C vs. UnC), brain damage, wakefulness vs. other states etc. • Attention and automaticity • Subliminal perception • Implicit learning and memory • Neuropsych, neurobiolgical • An inferred construct like attention, working memory etc.
Scientific Approaches to the Study of Consciousness • Operational definition (from Baars, 2003). Conscious processes are events that • Can be reported and acted upon • With verifiable accuracy • Under optimal reporting conditions • Little delay between event and report • Which are reported as conscious • Contrast with ‘fringe consciousness’ (e.g. familiarity)
Scientific Approaches to the Study of Consciousness • An UnConscious event is that in which • Knowledge of its presence can be verified • Even if that knowledge is not claimed to be conscious • And it cannot be voluntarily reported, acted on, or avoided • Even under optimal reporting conditions
Conscious Mediated Strategic control Limited capacity Voluntary Declarative memory Supraliminal Novel stimuli Wakefulness, dreaming Episodic Explicit cognition Attended stimuli UnConscious Immediate Automatic No capacity demands Involuntary Procedural Subliminal Routine, predictable Deep sleep, coma Semantic Implicit cognition Unattended input Distinctions in cognitive psychology
Return to subjectivity • Philosophers who suggest that science will never solve the problem of subjectivity essentially do not allow for comparisons of subjective states • In doing so are not allowing consciousness to be conceived of as a variable to be studied • However the scientific study of C is studying the subjective nature of consciousness, assuming what a person reports and the findings seen have at least some correlation to what a person experiences • Could we possibly assume that it had no correlation whatsoever? • Regardless of the ‘hard problem’, scientific study of consciousness is routinely carried out and knowledge gained
Some findings: Vision • Blindsight • People with damage to visual cortex can nonetheless ‘see’ objects in their environment • Milner and Goodale (1995) suggest that there are two vision systems: visual perception and visuomotor control. • Only the former is involved in conscious awareness. • Example: • Patient shown a circle with lines inside will report not seeing anything • Asked to indicate whether the lines are horizontal or not, patient can respond above chance
Some findings: Vision • Split-brain patients • Left half doesn’t know what the right is doing • Hemispheric Lateralization • Motor control • right brain - left side • left brain - right side • Visual field • right brain - left visual field • left brain - right visual field • Lateralization of function • Primary language areas on left, in most people
The split brain • Hemispheric coordination by means of the corpus callosum • Disconnecting the Hemispheres • Treatment for Epilepsy • Commissurotomy • Now they only snip anterior part of the CC • Normal responses under normal conditions or only subtle effects seen • Unusual responses under laboratory controlled conditions • If something is displayed to the LVF, the person cannot name (is not aware of) the object • Information from the right hemisphere does not get to the left • The can however reach for the correct object with their left hand
The split brain • So really, only the left side can report being conscious at all • At least initially, the right can learn to speak to some extent also, and is already implicated in aspects of language such as metaphor and humor • So right brain is largely mute, but inability to speak is not the same as lack of consciousness • However the language - consciousness-as-we-know-it link is strong. Perhaps it is language that allows us to get a sense of self… • "When I learned the meaning of 'I' and 'me' and found that I was something, I began to think. Then consciousness first existed for me". • ~Helen Keller • At the very least suggests consciousness-as-awareness is not unitary
Some findings: Vision • Hemineglect • Cannot attend to info in half the visual field • Can still make same/different judgments above chance • Can still show priming effects for stimuli in the neglected hemifield
Some findings: Attention • Mackay (1973) • Unattended information is processed for meaningful content, though this happens subconsiously • Schneider & Shiffrin (1977) • Automatic vs. controlled processes • Automatic operates independently of subject’s control, and independent of attention; Does not use up processing resources • Findings discussed regarding change blindness and inattentional blindness suggest attention is a necessary component to consciousness awareness • No attention means no awareness • However may also suggest that what we think consciousness is may be way off
Some findings: Memory • Tulving’s (1985) Types of Memory related to Consciousness • Anoetic consciousness • Neither awareness of knowledge nor of personal engagement (procecdural) • Remembering how to do things • Noetic • Awareness of knowledge based on experience, but without awareness of personal engagement (semantic) • Remembering what it is • Autonoetic • Awareness of personal engagement in remembered events and experiences (episodic) • Memory for a specific episode of experience
Some findings: Memory • Schacter et al. (1986) • Hippocampal involvement in conscious recollection of studied words • Reber (1989), Shanks & St. John (1994) • Implicit & Explicit learning and memory (or not) • Learn materials, skills consciously, the details may not reach awareness
Some findings: Memory • Retrograde Amnesia • Failure to remember events prior to injury • Often caused by head trauma • Anterograde Amnesia • Failure to remember events experienced after injury • H.M. • Korsakoff’s syndrome • Selective brain injuries • Priming can be as good for amnesiacs as for controls • “Procedural memory” like that in Towers of Hanoi
H.M. • H.M. • Surgical removal of hippocampus on both sides of brain to treat epilepsy • Retention of ordinary short-term memory • Retention of information from before operation • Failure to learn new information • Unable to find his way to his new home unless he can see the location of the house • Has normal initial conversations but has no memory of the meeting if the person leaves and returns • Shows learning of mirror-tracing, but has no memory of doing so
States of Consciousness • Normal Waking State • The “stream of consciousness” • Daydreaming • Altered States of Consciousness • Near Death & Out of Body Experiences • Meditation & Sensory Deprivation • Hypnosis • Sleep • Other Induced States • Drugs • Activities
States of Consciousness • Anesthesia • At what point is Consciousness ‘turned off’? • Thalamus (e.g. Alkire, Haier & Fallon, 2000) • Drugs in general produce a wide variety of ‘states of consciousness’, from nicotine to heroin • Activities (sex, running) can also produce changes in brain states and thus conscious states
Sleep and dreams • Dreams • Dreams as a form of thinking • Mnemonic activation • Lucid (LaBerge et al., 1981) • Characteristics • Sleep mentation • Thoughts while sleeping • Dream qualities • Imagery • Temporal progression • Narrative coherence
When Dreams Occur • Hypnagogic State • Onset of sleep • May be characterized by vivid imagery • NREM Sleep • 10-40% yield dream reports • Often static images or isolated thoughts • REM Sleep • 80-90% yield dream reports • Usually images in a narrative
Dreams as a Form of Thinking • Dreams are symbolic acts • Dreams are based on what we know • Children have simpler dreams than adults (or lack the language to describe the complexity) • Dreams use dissociated pieces of memory and knowledge • Dreams are organized • Dreams have realistic features • People are people; objects are real