FINAL Flashcards
2 higher order theories of consciousness (HOT)
- higher-order perception
- higher-order thought
higher-order perception
idea that consciousness arises when you acknowledge yourself perceiving other things
higher-order thought
idea that humans are aware of thought processes, and this brings about consciousness
3 criticisms for higher order theories
- we are aware of stimuli, not thoughts about stimuli (meta-thought is not necessary for consciousness)
- doesn’t take conscious action into account
- no neuro basis
global workspace theory (GWT)
- input processors compete for attention (similarly to pandemonium -> loudest will enter consciousness/workspace)
- (conscious) global workspace broadcasts input to other brain areas for voluntary action
what 3 things does GWT account for
- intentional action
- information retention
- planning and creative thought
global neural workspace theory (GNW)
used fMRI to map brain areas with different functions, these propagate signals across to motor systems to organize voluntary action
what structure is thought to account for consciousness and why according to GNW
pyramidal neurons because of widespread structure that can connect many areas including PFC and temporal lobes for voluntary action
monism
body and mind made of one substance
dualism
body and mind made of two distinct substances (possibly connect through pineal gland)
functionalism
mental states are constituted only by their functional roles (i.e. accounts for multiple realizability); brain = hardware, mind = software
reductionism
break everything down into parts, no longer discuss the whole
advantage of reductionism
easy to test each individual part
disadvantage of reductionism
some things can’t be broken down
emergence
sum > parts e.g. janitor’s dream
rat memory experiment setup
play a tone, then shock the rat. if they remember, they should be afraid every time they hear the tone.
how to prevent a rat from learning new things
administer drug while / near the time of the initial shock
how to prevent a rat from remembering things
administer drug during recall, it will alter the original memory
can the rat memory experiment be done in humans and is it effective
yes, drug was used with PTSD patients and was somewhat effective, it makes the painful memory less painful
best way to preserve a memory in its original form
don’t recall it
why can we never be 100% certain about material reality (& order of processing pipeline?)
real world -> senses -> processing -> awareness; reality is always filtered through senses and processing therefore never 100% objective
cartesian theatre
example of higher-order perception (perceive yourself perceive something)
problem with cartesian theatre
if homunculus is another person inside your head, what about their consciousness?
Dennett multiple drafts model
different senses have different processing streams where they process things intermittently, and objects can reach ‘fame’
‘fame’ (multiple drafts model) & what is it related to
related to GWT; something that reaches awareness when not being processed, and is broadcast to other brain modules
‘draft’ (multiple drafts model)
there can be multiple version of one stimulus in one stream due to lots of processing
can stimuli continue to be processed after they reach fame
yes
David Eagleman task summary
- monitor motor cortex
- high specificity watch
- any time you feel urge to press button, note the time
- up to 2 seconds before reporting feeling urge, brain has already made the decision for you (without your awareness)
therefore do we have free will?
eagleman democracy of mind
rivalling streams competing for attention (similar to pandemonium
3 features of eagleman democracy of mind
redundancy, competition, emotional + rational processing
redundancy of democracy of mind
each stream is processed by multiple competing systems
competition of democracy of mind
e.g. pandemonium, which stream is loudest
emotional + rational processing of democracy of mind
both kneejerk processing and more rational
what does IIT slicing allow for
seeing which systems are affected lets you determine which systems are dependent on each other vs independent
what is phi value when slicing
number of dependent subsystems
what does a high phi value mean (theoretically)
more consciousness
negatives of IIT (5)
- panpsychism
- hard to calculate
- possible to ‘hack’
- just an opinion
- no definition for consciousness but now we have a number?
structural brain imaging (2)
plus 2 examples
- shows anatomy
- used for tumors, strokes, lesions. etc
- CT and MRI
functional brain imaging (2) plus 3 examples
- shows blood flow / electricity
- used during experiments and diagnosis
- fMRI, PET, EEG
Computed Axial Tomography (CAT / CT) scan
slice by slice through brain (white = bone)
MRI
machine shoots radio waves at tissue, only H responds, creates excitation, H stores info, then measure H activity (white=bone)
CT advantages over MRI (3)
- better spatial res
- cheaper
- faster
MRI advantage over CT
- better contrast
fMRI
(multiple scans)
oxygenated blood -> processing -> deoxygenated blood
areas where blood is being deoxygenated light up (blood oxygen level-dependent (BOLD) signal)
Positron emission tomography (PET) scan
(rainbow scans)inject radioactive glucose, brain activity uses sugar -> see glow more
fMRI advantages over PET (3)
better spatial and temporal res, no radioactivity
PET advantages over fMRI (3)
- faster
- quieter
- cheaper
EEG advantages (5)
- fast
- cheap
- safe
- direct relation to brain activity
- good temporal res
what type of scan do we not have yet
full CNS scan
how do diff types of memory differ (3)
capacity, duration, content
2 types of sensory memory
iconic (visual = 250-200ms) and echoic (auditory = several secs)
why no olfactory, gustatory and tactile sensory memory
difficult experimental protocol
normal capacity of sensory memory
4-5 items e.g. letters
what did Sperling find sensory memory capacity could be extended to with training
9-12 items e.g. letters
what happens to sensory memory with a 1s distractor (masking)
removes majority of it (back down to like 3 items)
what happens to sensory memory with a cue to indicate direction (too short for conscious awareness)
restores performance
how do blinking vs blank screen affect sensory memory
blinking = disrupts performance
blank screen does not
working memory duration without rehearsing
18s
working memory capacity (& how to improve it)
7 +- 2
chunking
3 types of coding for working memory
- acoustic (e.g. get confused because stimuli sound the same)
- semantic (e.g. get confused because categories have similar meanings)
- visual (e.g. rotation tasks are processed degree by degree)
is working memory scanning done in serial or parallel, and how do we know (in lab) (2)
& caveat to these results
- RT linearly correlated to set size (7+-2)
- we don’t terminate as soon as we find the number = exhaustive (not serial)
- perhaps only parallel processing because we want to do well in lab
2 types of LTM
explicit/declarative and implicit
2 types of explicit/declarative memory
semantic and episodic
implicit memory =
procedural
why is assessing LTM capacity hard
must max it out = how?
- hard also because of memory reorganization
LTM duration (3 phases)
- rapid decline over first 3y without reinforcement
- stable at 75% for ~25-30 years
- another decline, possibly due to general cognitive decline
how does better learning/memorization affect LTM duration
higher starting point, but curve stays the same
coding explicit/declarative memory
various locations across cortex (distributed representation)
coding implicit memory
production (e.g. if then rules) in cerebellum
what did Lashley find about LTM location (engram)
takes longer to retrain a rat depending on the size of the brain chunk that was removed, but rat does not forget
equipotentiality (Lashley)
brain areas can take over for each other after damage
Hebb rule
neurons that fire together wire together
long-term potentiation (LTP)
high freq = more receptors develop on receiving neuron
HM (procedure and result)
removal of hippocampus = anterograde amnesia (no new memories), but all memories up to that point are intact
hippocampus function
memory consolidation
why is cognitive science reverse-engineering
we are trying to figure out how an already existing thing works
machine definition
any cause-effect system
4 features of computation (and what is it ultimately)
- rule-based
- shape-based
- implementation-independent (i.e. multiply realizable)
- semantically interpretable
aka symbol manipulation