Sensation II and Classical Conditioning Flashcards
(37 cards)
where is the primary visual input receiver?
occipital cortex back of brain
What is the specific name of this region?
V1
What happens with v1 damage?
cortical scotoma, complete loss of visual sensation for specific regions, people dont realise because the brain just fills it in.
what are some characteristics of v1
v1 encodes for the opposite side left encodes right eye info. hence one v1 on each side too. important for visual processing
what would left damage to v1 cause?
loss of visual space to right side and vice versa
what is chromatic flicker
light changing from red to green happens fast enough we just see a solid colour (yellow)
v1 responds to the changes without us knowing so some must be subconscious
What happens with v1 removal/damage though?
can still perform some visual tasks when blind (navigating). Letter example action dichotomy.
what does signal detection theory do??
measures sensitivity to physical conditions under conditions of uncertainty.
its also a recognition of pattern activity that can help differentiate things
what are the criterion people adopt?
relaxed (everything even close to being something is that thing)
tight (I need to be extremely sure the thing im thinking is that thing)
What are the two types of rates used to test in signal detection theory?
hit rate: when a physical signal is presented
false alarm rate: when a signal isnt presented but they say it is
how do you measure hit rate
HR = hits/ hits +misses
how do you measure false alarm rate
FAR = FAs/FAs+CRs (correct rejections)
What can HR and FAR help us estimate?
Bias: tendency to report a signal
Sensitivity: ability to see a signal or not
How do we work out detection levels?
discriminability index (d’)
if HR = FAR, d’ = 0
if HR > FAR, d’ > 0
What would it indicate if someone was missing signals in the SDT test
they would be saying there isnt a signal when there was
What is criterion drift?
when your stability of a signal is changed due to the unexpected vs expected outcomes
what are some practical applications for SDT
airport security and fingerprint analysers
What is weird about blindsight?
people perform above average in tests. Showing that v1 is important in visual awareness.
What is functional modularity?
there are multiple brain regions analysing information at different locations and times integrating them over time.
why do people still functiona little after V1 damage?
other pathways can take over older, dormant ones such as v5.
What is learning?
Modification of behavior or thought through experience
What is simple learning?
doesn’t tell us how connections between stuff is formed
change in strength of a response due to a stimulus (slug water)
What is habituation
reduced intensity of reflex response eventual ignoring of reflex (keep blasting slug wont retract gills)
sensitisation?
more intense response makes the stimulus important (shock vs water jet)
