L8 Flashcards
what is episodic memory
what and where something happens
what was seen when HM was asked to estimate time
Short term memory last for about 20 sec therefore when asking Hm about time he can do it fine for under 20s but after that his performance drops off
what is a core deficit with patients with hippocampal lesions
their inability to narrate events in the order in which they happened
when hippical lesson patients were compeered to normal individuals what was seen when asked about their memory of sequences of events
there memory was very poor and when they wee first asked there recall was about the same as the controls a month later
what is recognition memory
if you were to present an individual with hippocampal damage with a word. they would not remember the word at a later date but if you asked them to guess then they would guess the correct thing
how would you use recognition memory to test for sequential memory in hippocampal damage patient
by giving them paired words eg locomotive dishtowel and then ask them what order that you presented the word to them they will preform as well as the controls do
what provides evidence that there are time cells in the hippocampus
if you get a rat to run on a treadmill for 15 sec then different cells will fire in the hipp at different time points
what do time cells in the hipp suggest
If time perception depends on activity in neural systems then perception can be altered by changes in neural system activity
what would happen if the internal clock speeds up
time estimation will feel longer
THC does this
what is chronostasis
the feeling of time stopping
what causes chronostasis to happen
During Saccade – visual system suppresses input
Upon Fixation – nervous system fills in gap retrospectively
if you move your eyes rapidly (eg less than 100ms) then the shifting gose would be blurry so the nervous system inhibits visual input and fills in the gaps
what is the flash lag illusion
The blue looks bigger than the red but the squares are the same size
This happens because the nervous system is predicting where they expect to see the square
Therefore you are seeing it where it is going to be not where it is
This is because the brain is more interested in what is going to happen next not what is happening now
what is predictive perception
when the nervous system detects something where it will be rather than where it is
does time slow down when in near death situations
there is no evidence for this
what is reactivation
content-sensitive
patterns of neural activity expressed during perceptual experiences are re-expressed when experiences are remembered
activity mapping between encoding and retrieval is not exact.
Why might that be?
because of noise in the system
distinct origin of inputs (perceptual vs temporal cortex)
shifts towards conceptual representations (consolidation)
reconsolidation of memory
what is consolidation
going from an active liable state to a inactive fixed state
this takes time
why do some memories endure (with example)
we recall memories that have emotoions linked to them
when 9/11 witnesses were asked to recall events of that day. the ones that were closest to the attack had the highest level of arousal because the closer you were the stronger the memories
what have animal studies shown in relation to the CNS and memory
Animal studies show that memory is enhanced by administration of low doses of CNS stimulants to rats and mice shortly after training,
but not after a delay period
what is, where is, and what does adrenaline do
Is both a hormone and a neurotransmitter.
The adrenal medulla,
the inner portion of the adrenal gland, regulates and secretes adrenaline in response to stress.
It produces a rapid reaction – fight or flight response •increased heart rate and blood flow •faster breathing •raised blood sugar levels •increased strength and physical performance
adrenaline does not cross the blood brain barrier very well. how does it effect the brain
influences the brain via activation of the vagus nerve
Therefore the signal gets to the brain but not directly
what is cortisol
A steroid hormone in the corticosteroid class of hormones
what is cortisol involved in
Involved in a range of processes including metabolism and
immune response
when used as a medication what is cortisol called
hydrocortisone
what triggers the release of cortisol
stress this is a slow response
where is cortisol produced and what controls the release
produced primarily by the adrenal glands
Release controlled by the hypothalamic–pituitary–adrenal (HPA) axis
cortisol is able to cross the BBB well
yes
what part of the brain do cortisol and adrenaline effect/what do they do here
the amygdala
they increase the likelihood that those memories will be consolidated by increasing noradrenaline which modulates the hippocampus, cortex and other brain regions
what is memorie for
Episodic future thinking (EFT): Imagining or simulating a specific episode that might occur in ones’ personal future
People with hip damage not only don’t have good memory of the past but they also cant imagine what is going to happen in the future
if people have better episodic memory what does this mean in the hippocampus
that it is bigger
