Lecture 22 - Consciousness Flashcards
What is consciousness
Explaining PHENOMENAL awareness - subjective experience:
–> the feel of private sensory experience, inner thoughts, and feelings, action intentions
Phenomenal Awareness: The Mary Colour Thought Experiment
Mary was brought up by an evil philosopher who put contact lenses on her eyes immediately after birth so that she would see the world monochrome (in black, white and grey).
–> All her life Mary intensively studies everything to do with colour vision.
–> By the time she is 35 she knows everything there is to know about colour vision.
On her 35th birthday she is given a red rose and her contact lenses are taken out. What do you think will Mary say?
* ‘Oh, that’s exactly how I thought red would look like’ or ’Wow! So, that is red!’
- idea: the knowledge about the physical properties of the universe could not prepare her for the sensation of seeing red –> something very PRIVATE and initiative for us but difficult to explain
What is self-consciousness
Representation of
o the bodily self
o the self as the subject of experiences
o the self as “owner” of actions and intentions
–> the correlates of consciousness: what kinds of process/representation in the mind/brain are associated with phenomenal awareness (STILL UNKNOWN)
Why is consciousness so difficult to study/explain
It is SUBJECTIVE and PERSONAL
What are some neuropsychological disorders of self-consciousness?
Anosognosia’s - not acknowledging major and frank cognitive disorders (eg. Anton’s syndrome; they are blind but convinced they are not blind
Anarchic Hand: loss of awareness of ownership of intentions
Alien Hand/Phantom Limb pain (impaired awareness of ownership of body parts)
Psychotic Auditory Hallucinations = loss of awareness of intention of INTERNAL SPEECH
What cognitive functions are associated with awareness?
Obviously: no conscious access to early stages of sensory analysis but we tend to think:
Sensory analysis perception, interpretation motor
processes –> decision, intention –> control
(unconscious) (conscious) (unconscious)
ALSO: many in-between processes are just as unconscious as sensory and motor processes (eg. syntactic processing)
Numerous aspects of “higher” cognition that we would once have thought of as requiring consciousness can happen WITHOUT awareness
Activation of meaning: outline the role of priming
Can happen WITHOUT awareness
–> The standard assumption would be that to apprehend the meaning of a visual object, you have to ‘see’ it
Semantic priming is a psychological phenomenon where exposure to one stimulus influences the response to another stimulus that is semantically related, making the latter easier to process or recognize
Semantic priming obtained from backward-masked words with prime duration at which presence of word cannot be discriminated –> similarly: masked category priming of pictures, words, faces etc.
Activation of meaning by subliminal or unattended objects/events
It is possible to find conditions (eg. brief masked presentation) where there is enough processing of sensory input to activate meaning, emotional salience etc. BUT there is no perceptual awareness of stimulus
Claims remain controversial because of methodological difficulties…
- establishing total invisibility of prime
- ruling out priming due to perceptual overlap
- ruling out response priming
Unattended words outside focal attention: not noticed or remembered, but undergo some (attenuated) semantic processing (eg. GSR to shock conditioned words in unattended message)
Priming to Behaviour: Outline the research by Bargh et al. (1996)
Bargh et al. (1996)
–> Participants believing they were in a language experiment assembled into sentences
o Words associated with age OR
o Control words
Walking speed down corridor SLOWER after priming with age-related words!
Issues with replication - publication bias, etc.
Can a Subliminal Stimulus initiate a voluntary action?
Naive Model of Voluntary Reaction to a Stimulus
sensory —-> SEE —-> DECIDE —-> Motor
processes stimulus to act processes
{ ------- conscious --------}
Implies you have to consciously SEE a visual stimulus and INTENT to act to perform a voluntary action
What is blindsight?
Patients with a HEMIANOPIA - area of blindness in the visual field due to cortical V1 damage - have no conscious awareness of stimuli in the blind region
–> But (if forced to guess) can voluntarily point at a moving object within the blind region, and make some discriminations of them (form, colour) or navigate obstacles
When does awareness of intention happen relative to initiation of action?
Libet’s ERP Paradigm
–> P raises finger when they feel like it
–> And judges the moment W at which they consciously initiated action
Readiness-potential onset substantially precedes judged moment of intention to act
–> same is true for briefer “lateralised readiness potential” associated with selection of left versus right response
–> awareness FOLLOWS response selection?
Are we aware of the choices we make?
People happily given reasons for choices they didn’t make and provide a post-hoc rationale for why they made that choice
Is ANY process/representation ALWAYS associated with awareness?
Much happnens in our heads to which we have NO ACCESS
–> there are many kinds of mental representations that turn out NOT to need awareness
o activation of meanings and emotions
o stimulus-triggered or spontaneous action
o some kinds of choice and decision-making
Is ANY process/representation ALWAYS associated with awareness?
–> perhaps serial logical system (thinking?)
–> perhaps the mental/situation model
