final

Question 1

MVPA or multi-variate pattern analysis

Answer 1

Predicts the stimulus someone is seeing or remembering based on their brain responses, this is done by considering the patterns across voxels or electrodes. Each voxel contains 600,000 neurons. MVPA decodes relationship between activity and remembered stimuli.

PFC has sustained activity during delay, but patterns of BOLD activity do not carry reliable information about stimulus. Visual cortex does not show elevated activity, but pattern allows you to decode stimulus held in STM, unclear whether pattern in visual cortex in STM is the same as during perception

Question 2

prepotent response/stroop effect

Answer 2

When a stimulus has a response strongly associated with it, we call that a PREPOTENT response. We experience conflict when a prepotent response SHOULD NOT be enacted.

Example: the Stroop effect. Say the color the word is: GREEN

Question 3

Environmental dependency

Answer 3

Patient dependent on environmental cues can’t help but mimic. can’t inhibit prepotent response… “distractor inhibition”

Question 4

Perseveration: card sorting task

Answer 4

cards sorted with a rule in mind. After 10 correct trials, the rule is switched. Measure is to see if they change their strategy. If they continue to sort according to the old rule, they are perseverating. LFL damage doubled the rate of perseveration.

Question 5

Effects of LFL(Lateral Frontal) damage

Answer 5

Suggestion: LFL damage causes a failure to inhibit prepotent incorrect responses OR a failure to inhibit distracting information OR a failure to boost the correct response

Question 6

A not B error

Answer 6

perseveration is natural during development. Perseveration on recently rewarded response. Overcome through development or through functioning of the PFC.

Question 7

Dopaminergic neurons in the Basal Ganglia

Answer 7

these signal subjective reward, error signal telling rest of brain if wrong or right

Question 8

DA neurons in PFC

Answer 8

PFC has some of the highest density of DA neurons. PFC also has many more recurrent (self) connections than other areas. DA acts as a clamp, turning on PFC clamping into a pattern of activity, or turning off PFC and allowing a new pattern to form. PFC locks into a pattern of activity when a stimulus is rewarding.

Question 9

what is a decision, why are decisions hard

Answer 9

A decision is a deliberative process that results in the commitment to a categorical proposition.

Decisions are made hard because of NOISE.

Question 10

Signal Detection Theory

Answer 10

Momentary evidence only.
Assumes a single sample of evidence on every trial. Assumes noisy evidence (same stimulus will not always lead to same physical/neural response). Assumes two independent stages, sensory and decision/distribution and criteria. The amount of overlap in distributions determines the difficulty of the decision or the sensitivity of the system. Called d-prime. Placement of criteria determines willingness to have false alarms and misses.

Question 11

perceptual decision making occurs where?

Answer 11

MT (medial temporal)

Question 12

In signal detection theory, we can think that microstimulation to the MT area: _________?

Answer 12

biased the internal response to both null AND preferred motion

Question 13

Motion coherence

Answer 13

the percentage of dots moving in same direction

Question 14

Accumulated evidence about a response is represented where?

Answer 14

Accumulated evidence about a response is represented in LIP (Lateral Intraparietal)
MT (Middle Temporal) provides Momentary perceptual evidence about direction of motion
LIP goes to FEF (frontal eye fields) and SC (superior colliculus) as well as MT
The LIP (Lateral intraparietal sulcus) has perceptual and motor neurons

Question 15

motor neurons and motor fields

Answer 15

Motor neurons have a ‘motor field’, a location in space where a monkey will make an eye movement when that neuron is stimulated. Experiment takes advantage of this by making the response be a Saccade either in or out of the LIP motor field. Motor fields are not stimulus dependent, they are response dependent

Beta oscillations in the human motor system are thought to also represent accumulated evidence for an action

Question 16

Common Currency and the OFC (Orbitofrontal cortex)

transitivity, value transitivity, menu invariance

Answer 16

Rational decisions require:
Transitivity= A>B>C, so A>C
Value Transitivity= If A is worth twice as much as B, then 2B should be taken as often as A
Menu Invariance= The value of B is the same whether we’re comparing to A or C
If these properties are satisfied, then the item is in ‘common currency’

Question 17

OFC (orbitofrontal) represents which type of rational decision property?

Answer 17

Menu invariance

Question 18

Kluver-Busey syndrome symptoms

Answer 18

hypersexuality, visual agnosia, hyperappetite, etc

Question 19

Amygdala damaged test with faces

Answer 19

First impression test with faces, how much do you trust this person? Ratings were different from sample, but this only applies to visual stimuli. When given verbal description, ratings same as controls
fMRI responses in amygdala correlate more to how a face is rated by a group than the specific individual being scanned
Why? Many idiosyncracies in determining whether or not a face is likable. Group average will not reflect such factors, and apparently, neither does the amygdala, responding based on inherent likability of the face. This is ‘evidence for implicit processing in the amygdala’
Effect went away when pictures were of ‘positively regarded’ black and white men, this suggests that implicit processing in the amygdala is actually learned, not innate/hardwired

Question 20

Two types of learning in amygdala:

Answer 20

Pavlovian conditioning: pairing of neutral stimulus(CS) with noxious stimulus(US), caused the behavioral response associated with noxious stimulus to be associated with nuetral stimulus
Avoidance learning: Context dependent behavior that results in the avoidance of the CS.

Question 21

Circuitry of amygdala

Answer 21

Lateral nucleus of the amygdala is the convergence of CS and US through LTP
Central nucleus accepts output of LA, so also critical for conditioning
Basal nucleus outputs to Basal Ganglia avoidance system and so critical in avoidance learning

Question 22

Vigilance Theory

Answer 22

Seeing whites of eyes indicates how afraid someone is. Not alarming in itself, but says that there is danger nearby. If amygdala signals vigilance , it would be more active in response to the eyes-wide-open stimulus than others. And it is.
So the amygdala seems to do a quick and dirty analysis to tell the rest of the brain if there is anything that requires a state of vigilance.

Question 23

Amygdala role in remembering emotional events.

Answer 23

Setup: Emotional events are usually remembered better. Amygdala lesion patients showed the same effect as those who were on beta-blockers in a study of emotional story recollection

Emotional response in the fusiform face area(FFA) is also conveyed by amygdala

Question 24

vigilance signal learned by:

Answer 24

Vigilance signal learned by conditioning and other processes such as avoidance learning This vigilance signal has widespread effects and mediates how emotional memories are encoded

Question 25

emotional response in the fusiform face area conveyed by

Answer 25

amygdala

Question 26

Vegetative state or unresponsive wakefulness syndrome.

Answer 26

Associated with cortical damage. ARAS still intact, but patient unaware of themselves and their surroundings

Question 27

Reticular activity or just arousal is not enough for consciousness. The other things that are needed are:

Answer 27

complex cortical activity and substantial cortico-cortical and cortico-thalamic connectivity.

Question 28

The Lower Order Representation Theory

Answer 28

All you need to be conscious of something is for your brain to represent that information. I.e. V1(primary visual C) suffices for consciousness. V1 damage equals blindsight, eyes work but visual consciousness does not

Question 29

Recurrent processing theory:

Answer 29

Feedback and feed-forward. Feedback from higher order brain areas to lesser is responsible for conscious perception. Also been used to explain visual masking
There are huge priming effects irrespective of visual overlap. Invisible or masked words still activate the visual cortex. The difference between visual and invisible is widespread activation in parietal and frontal cortices.

Question 30

Global workspace theory

Answer 30

consciousness and reportable consciousness differ. Maybe the frontal/parietal activity is related to reporting/introspecting, not consciousness per se

Question 31

Optokinetic nystagmus response(OKN) / no-report paradigm

Answer 31

Frontal activity went away when patients did not have to report their perceptions.

Question 32

Short term memories not stored in PFC, so Stimulus info could be decoded from:

Answer 32

visual area, “sensory recruitment” account of STM

Question 33

Action potential:

Answer 33

1 Resting membrane is hyperpolarized.
2 Depolarized by incoming signals. The voltage gated Na+ Channel opens only when a large depolarization is detected. Voltage gated K+ opens slightly slower. Push Na out and bring K in. 3 Membrane potential repolarized by K+, propagates by activating sequential Voltage gated calcium channels channels,
4 resting potential reached again by action of Na/K pumps

Question 34

Laminar organization of V1

Answer 34

vertical and horizontal electrode penetration. IV is primary input layer, hypercolumn, ocular dominance columns left/right/left/right

Question 35

Basilar membrane: Place code and rate code.

Answer 35

Base does not respond to bass.
Place code: Different frequencies of sound are represented in brain according to where along the basilar membrane is stimulated
Rate code: different intensities/amplitude of sound represented by firing rate of auditory nerve neurons.

Question 36

Object recognition in temporal cortex: Reduction method

Answer 36

take parts of an image away. Neuron continue to respond until image gets too basic/simple. Suggests that response was not to e.g. a tiger’s head but rather simpler configuration of basic elements. Different IT neurons driven by different stimuli

Question 37

Posner cue

Answer 37

Arrow tells person where to focus attention.
[X] [ ] Neutral cue
Demonstrates benefits of (covert spatial) attention. Valid is faster than neutral. Invalid is SLOWER than neutral, not the same. Supports the idea that attention can be drawn without moving one’s eyes

Question 38

spatial attention feed-forward processing

Answer 38

PFC -> TRN (thalamic reticular nucleus) -> LGN (lateral geniculate nucleus)/ thalamus

Question 39

Multivariate pattern analysis - faces/houses test.

Answer 39

This was evidence against localization of function/ evidence in favor of distributed processing. The different objects did not active discrete neurons.

Question 40

Neurobiology of memory: 2 types of glutamate receptors, NMDA and AMPA. What about NMDA? (long term potentiation)

Answer 40

NMDA has magnesium ion that only opens when post-synaptic neuron already depolarized
NMDA receptor lets calcium ions into the cell, this triggers intercellular mechanisms that:
1 Produce more AMPA receptors in synapse
2 Create entirely new synaptic terminals.
This is called long-term potentiation

Question 41

Reconsolidation

Answer 41

When memories retrieved, reconsolidation is thought to occur to return them to “labile state”? Make them stronger I guess. The rat fearing the tone test. Memory removing drug made the rat stop fearing the tone.