consciousness Flashcards
what is conciousness
sensory awareness of the environment
access consciousness - Block 1995
being aware of something - we are unable to name it/remember it ect.
phenomenal consciousness - Block 1995
refers to the experiential aspects - what it feels like to taste chocolate eg
conscious - freud
thoughts and feelings we are aware of
preconscious - freud
material you are not currently aware of but which is readily available
unconscious - freud
material which is unavailable to consciousness under most circumstances
non-conscious - frued
refers to bodily processes which cannot be experienced through sensory awareness
structuralists - wudnt - introspection
understand components of consciousness eg the smell of a rose
behaviourists - watson
concept of consciousness should be eliminated from psychology - criticising the value of introspection in psyc
hypnosis
altered state of consciousness in which people are suggestible and behave as though they are in a trance
where else is hypnosis used
by dentists and doctors as an anaesthetic
how do psychologists use hypnosis
to help clients reduce anxiety, overcome fears or lessen perception of chronic pain
how do the police use hypnosis
to prompt memories of witness
5 key questions in consciousness research
- altered states of consciousness
- role of attention
- importance of unconscious processes
- the hard problem
- cognitive neuropsychology
what is the ‘hard problem’ - chalmers 1995
the question of how physical processes un the brain give rise to subjective experiences
how is cognitive neuropsychology a key question in consciousness research
effects of brain damage -
automatic cognitive processes
relatively unconscious - we have little awareness of their operation
- no capacity limitations
- dont require attention
- very hard to modify once learned
controlled cognitive processes
associated with conscious awareness of what is being processed
- limited capacity
- require attention
- can be used flexibly in changing circumstances
what is cognitive research interested in
cognitive correlates of consciousness
what doesnt cognitive research explain
conscious experience but aids our understanding of the role of consciousness in cognition
what cognitive processes are associated with consciousness - cognitive research
selective attention - by focussing ones consciousness on a particular stimulus and ignoring others we become aware of items attended to
what is selective attention
being able to focus ones auditory attention on a particular stimulus while filtering out a range of other stimuli
eg cocktail party effect - being able to tune into one person
what type of stimuli capture out attention resulting in availability to consciousness
- sudden changes
- novel stimuli
- intense stimuli
- repetitive stimuli
when do models of selective attention differ
when material is selected for attention
early selection models
very little information about stimulus is processed before selection occurs - eg braodbent filter model
late selection models
more information eg semantics is produced before selection occurs
what did broadbent - filter model use
dichotic listening task - three digits presented to each ear
what did participants have to do in broadbents filter model
write down as many digits as possible done in one of two ways - ear-by-ear or pair-by-pair
what did broadbents filter model find
better recall ear-by-ear than pair-by-pair
what was the conclusion of broadbents filter model
attention can only be focused on one channel of information at a time and switching channels is difficult
what is the flow of the filter model - broadbent 4
- info to sensory organs
- stored in sensory memory
- filter allows only attended info to pass for further processing
- passed onto working memory (STM) and communicates with (LTM)
early selection model - processing
only sensory info processed before attentional filter
moray 1959
*ps told to switch attention from one ear to the other during dichotic listening task
what did moray find
were unable transfer attention from one ear to the other when given a verbal instruction to unattended ear
what would broadbent say about morays findings
that this info should have never been unattended - early selection based on physical characteristics of stimulus - hence meaning (instruction) should not be processed by unattended ear
attenuation model of selective attention - treisman 1960
- early selection model
* BUT unattended material can get through in a weakened (attenuated) form
threshold mechanism - attenuation model of selective attention
some info (based on semantic importance) may grab ones attention from unattended stream
lowered threshold - attenuation model of selective attention
for things like ones own name, words like ‘fire’
visual perception
assumption that visual perception is a conscious process
-we are consciously aware of the objects we are looking at
change blindness
inability to notice that an object has moved,changes/disappeared
*no conscious awareness of large changes in the visual scene
inattentional blindness - Simons & Chabris 1999
- gorilla interrupts teams passing ball
- asked to count no. of passes made by one team
- 50% dont notice the woman in gorilla costume
Simons & Chabris - gorilla costume was black - % of detected passes made by white team
42%
Simons & Chabris - gorilla costume was black - % of detected passes made by black team
83%
mere exposure effect
prefer stimuli we have encountered before even if we are unaware of previous encounters
kunst-wilson & zajonc 1990 - procedure - perception without awareness
- novel black and white patterns presented too quickly for p’s to be aware of them
- later presented pairs of patterns (1 new,1 old)
kunst-wilson & zajonc 1990 - perception without awareness - what was p’s preference
chose old patterns even though they showed no conscious recognition of old patterns in explicit memory test
kunst-wilson & zajonc 1990 - perception without awareness - unconscious encounter
unconscious encounter with patterns changed their emotional responses to them (even with no conscious memory for them)
Vicar 1957 - subliminal perception
- flashed ‘eat popcorn, drink Coca-Cola’ for 1/300th sec during cinema film
- claimed 18% increase Coca-Cola sales, 58% popcorn??
was Vicar 1957 - subliminal perception evidence of perception without awareness
- too fast to be consciously seen, but evidence of behavioural change???
- however film (Picnic) contained scenes of eating/ drinking
Could this explain sales increases?
Persaud & Mcleos 08 - perception without awareness - method
- presented ‘b’ or ‘h’ for 10ms (short duration) or 15ms (long) duration
- Instructed to respond with letter that has not been presented
Persaud & Mcleos 08 - what did it examine
*willingness to bet on accuracy of their decisions
if consciously aware of letter, they should be willing to bet!
*Much more willing to bet with longer presentation even though they were generally correct even with shorter duration
Persaud & Mcleos 08 - generally correct responses suggested that
some processing of shorter duration stimulus had occurred, however unwillingness to bet on accuracy suggests they were unaware of it.
what did merikle et al o1 conclude about perception without conscious awareness
‘some processing of shorter duration stimulus had occurred, however unwillingness to bet on accuracy suggests they were unaware of it.
what are Merikle,Smilek & Eastwoods two main thresholds for conscious awareness of a visual stimulus
subjective threshold
objective threshold
subjective threshold
defined by an individuals failure to report conscious awareness of a stimulus
objective threshold
defined by an individuals ability to make accurate forced choice decisions about a stimulus
- often show awareness of a stimulus assessed by objective threshold even when the stimulus does not exceed subjective threshold
Erdelyi 1974 - perception without conscious awareness
Perception involves multiple processing stages/mechanisms with consciousness possibly representing the final stage of processing
*Hence a stimulus can receive sufficient perceptual processing to influence at least some aspects of behaviour without conscious perceptual experience
what is the challenge for researchers in terms of perception
need to develop more detailed theoretical accounts of unconsious/conscious perception
implicit memory
revealed by changes in performance on specially designed tests
Tulving, Schacter & Stark 1982 - implicit memory - procedure
gave lists of multi-syllabled rare words (e.g. ‘toboggan’) to participants.
*1hr or 1 week later completed a Fragment Completion Task: fill in blanks e.g. O_O_GA.
Tulving, Schacter & Stark 1982 - implicit memory - results
Participants unaware 50% solutions in list they were given earlier
*Repetition-priming effect - more correct solutions for items in earlier list
evidence for implicit memory being unrelated to explicit memory
- Recognition worse after 1 week than 1 hour,
* Fragment completion unaffected by time
implicit memory in amnesic patients
- often show impaired declarative memory (semantic and episodic) but intact procedural memory
- ability to learn new skills without remembering learning them
reading mirror-reversed script - implicit memory in amnesics - Cohen & Squire - general improvements
practice: increased speed
reading mirror-reversed script - implicit memory in amnesics - Cohen & Squire - - specific improvements
re-reading same text
*BUT no explicit memory for previous trials
neuropsychological patients
showed deficits in episodic and semantic memory BUT motor skills acquires at normal rate
neuropsychological patients and mirror tracing
improvement with practice (procedural memory)
*no conscious awareness of having performed the task in the past
amnesics
*reasonably good learning of sensorimotor and perceptual skills
amnesics and skill learning (procedural memory)
intact
Graf, Squire & Mandler 1984 - implicit memory in amnesics - part 1
rate how much liked words on a list
Graf, Squire & Mandler 1984 - implicit memory in amnesics - part 2
Memory test: 3 tests of explicit memory (free-recall, recognition memory & cued-recall) and 1 test of implicit memory (fragment completion) – e.g. STR_ _ (e.g. STRAP, STRIP)
Graf, Squire & Mandler 1984 - implicit memory in amnesics - examined
priming effects = extent word completions taken from lists in part one
Graf, Squire & Mandler 1984 - implicit memory in amnesics - results
amnesics worse on explicit but not implicit memory tasks
neuropsychology evidence
study of brain damaged patients with a partial lack of conscious awareness
Farah 01 - neuropsychological evidencd
‘what is different or missing in a patient who perceives without awareness, compared to a normal person who perceives with awareness’
prosopagnosia
condition in which familiar faces cannot be recognised consciously but common objects can however often evidence of subconscious recognition of faces
Young, Hellawell and de Haan (1988) - Prosopagnosics
decide as quickly as possible whether names familiar or not
Young, Hellawell and de Haan (1988) - Prosopagnosics - related priming faces
Performed more rapidly when presented with related priming face immediately before target name, even though they couldn’t recognise the face overtly
Young, Hellawell and de Haan (1988) - Prosopagnosics - covert recognition
larger skin conductance response (reflects physiological arousal) to familiar faces than unfamiliar ones even when overt recognition is at chance.
spatial neglect
Typically found after brain damage in the right parietal lobe, often as the result of a stroke (NB/ Information from left visual field goes to right hemisphere, whereas information from right visual field goes to left hemisphere).
neglect patients with damage to right hemisphere
do not notice (or fail to respond to) objects presented to the left (contralateral) side.
blindsight
- Damage to V1 (primary visual cortex) results in loss of conscious perception in parts of the visual field
- However can make some accurate judgments/discriminations about stimuli presented to ‘blind’ area
blindsight - Weiskrantz (1986)
Patient DB, blind in lower left quadrant of visual field. He could detect stimulus presented to this blind area/ its location BUT had no conscious experience (couldn’t say what it was!)
blindsight - Weiskrantz (1986) - results on guessing stimuli
If he was made to guess what the stimulus was he was generally correct! When shown he was correct (item in right visual field) - expressed surprise & insisted he thought he was just ‘guessing’.
blindsight - Weiskrantz (1986) - pathways from eye to brain
There are at least 10 pathways from eye to the brain, some of which can be used by blindsight patients.
