Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Systems Neuroscience > Block 4 > Flashcards

Block 4 Flashcards

1
Q

What properties can neuromodulators effect?

A

-synaptic strength-
neuronal excitability
-circuit dynamics
which all shape behavioral states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do neuromodulators effect the brain?

A

can have both diffuse, widespread effects and specific,
spatiotemporally precise effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

the effect any neurotransmitter has on behavior depends on what?

A

co transmission of other neurotransmitters/modulators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does dopamine modulate?

A

Reward, saliency, uncertainty, invigoration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what does seratonin modulate?

A

impulsivity, harm aversion, anxious state, punishment, withdrawl.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what does Noradrenaline modulate?

A

exploration vs. exploitation, network reset, unexpected uncertainty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what does ACh modulate?

A

memory consolidation, attention, expected uncertainty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

3 common characterisitics of Neuropeptides

A
  1. processed from precursor proteins and packaged into dense core vesicles
  2. they diffuse from their release site to act on distant neurons
  3. they act primarily on cells in the brain but can also act as signaling molecules in the periphery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how are neuropeptides secreted?

A

through dense core vesicles. usually paired w/ G protein coupled receptors. distance can be from nm to mm. Large dense core vesicles are not localized @ synapse. signaling is also spatiotemporal precise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

upon what does neuromodulator release rely?

A

2 calcium sensors, Syn-1 and Syn-7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

upon what does the duration of neuromodulator release rely?

A

calcium sensor Syn-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Does the same neuropeptide function uniformally across the brian?

A

No, neuromodulatory neurons can be functionally heterogeneous and influence specific behaviors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Neuromodulatory receptors

A

usually signal through G-protein coupled receptors which give them the ability to affect gene transcription, the flow of ionos across the cell membrane and the secretion of substances from the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

do neuromodulatory afferents primarly act on pre or post synaptic cells?

A

neuromodulatory afferents affect cellular signaling through both presynaptic and postsynaptic modifications!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do neuromodulators affect synaptic properties?

A

can affect syn props in many different ways depending on how/where they signal!

They can increase or decrease synaptic strength through the addition or removal of receptors from the postsynaptic membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

in what processes do neuromodulators play a role?

A

network development, migration, differentiation of axons, synapse formation, remodeling. They can also influence behavioral states by changing how a stimulus responds to a stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how do neuromodulators effect individual neurons?

A

neuromodulators alter the excitability of neurons by changing conductances, distribution and expression and gating properties of ion channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Oxytocin

A

love, sensory processing, locomotion initation, CPG modulation, social bonding, anxiolytic, analgesic, nocifensive, developmental, vocalization, learning and memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which parts of brain mediate Oxytocin in pain processing

A

Magnocellular (SON) vs. parvocellular (PVT) oxytocin (OT) signaling secretes OT to rest of brain and periphery through posterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does OT effect fear response?

A

small set of OT neurons (from PVN/SON) are involved in fear expression and their activation reduces contextual fear response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

OT role in pain processing (PVN)

A

Astrocytes in amygdala express OT receptors and are activated by OT released from PVN. Astrocytes then release D-serine which helps reulgate emotional states in response to pain. (also synapses onto SON neurons)

Nature paper also says OT from PVT to periaqueductal gray is an analgesic

project to vlPAG. OT increases pain threshold ( a result of decreased LTP) at synapses connecting WDR and C-type fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

OT role in pain processing (SON)

A

PVT OT neurons synapse onto SON neurons and WDR neurons in spinal cord. the release of OT onto WDR neurons decreases nociceptive processing and pain responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

OT in Pain processing overview

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is an internal state?

A

a centralized brain (+ body) state which integrates information about our external environment and internal physiological conditions to orchestrate appropriate behavioral and physiological responses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

how can we tell what an animal’s internal state is?

A

it’s inferred from observations of an animal’s overt behavior, systemic physiology, brain activity (LOF,GOF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

examples of internal states?

A

arousal, motivation, emotion, varying homeostatic needs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Are internal states mutually exclusive?

A

No, independent states are indepenedently controlled but can co-exist or compete with each other (e.g. hunger and fear)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Pleiotropy

A

each state influences multiple aspects of behavior and physiology in parallel, such as body temp, respiration, locomotion, sensory responsiveness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

persistence

A

the ability of internal states to produce behavioral and physiological responses that outlast the termination of the stimulus that initiated the response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

scalability

A

the ability of responses to scale with the magnitude of the stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

generalizability

A

the degree to which an internal state can produce responses to stimuli that are distinct from the original stimulus that elicited the response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

valence

A

the positive or negative affect associated w/ that state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

how to improve our understanding of an internal state

A

integrated multidimensional analyses including behavioral but also physiological measurements

improvements in methods to classify behaviors and internal states. This will involve making more measurements

make tools for behavior and neural recording, analysis

dive deeper into how brain encodes internal states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

how do we infer internal states?

A

measure behavior and manipulate experience. observe behaviora across multiple contexts.

inducing need states

observing motor transitions

higher-order behavior

multiple state interactions

individual differences

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Internal states can be controlled by….

A

discrete population of neurons

some neurons in specific locations may promote states like hunger, arousal, dwelling, thirst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

diverses organization of neural states

A
37
Q

what is/are the proposed fabric of internal states?

A

neuromodulators! they can target neurons across the spatial extent of the brain but w/in target regions act at the scale of intracellular signaling

38
Q

opposing brain states, mutually exclusive neuronal ensembles

A
39
Q

Define attention

A

means by which we focus and amplify behaviorally relevant info at the expense of filtering out irrelevant ones.

40
Q

objective of attention?

A

to maximize SNR

41
Q

why do we need attention

A

to limit expensive neural activity. pools computational resources to process information we deem most important

42
Q

Space based attention

A

attention directed to a location in space enhances neural responses and improves behavioral peformance

43
Q

Feature-Based attention

A

attention can be direct to stuff. Stimuli w/ some physical similarity, features can be selected and enhanced by attention independently of their spatial location

44
Q

Object-Based attention

A

attention can be directed to objects, defined as a coherent combination of parts

45
Q

top Down attention

A

voluntary, endogenous

46
Q

bottom-up attention

A

involuntary, exogenous

47
Q

Attention Signature: Increased spike rate

A

Potential implication: increases output singal

basically everywhere. LGN, V1, V2, V4, MT, IT, LIP, FEF, PFC

48
Q

Attention Signature: increased gamma-band LFP power

A

increases locally synchrounous synaptic activity
FEF,V4

49
Q

Attention Signature: increased local gamma-band coherence

A

potentially increases signal efficacy at post synaptic targets
FEF, V4, LIP

50
Q

Attention Signature: increased cross-area gamma-band coherence

A

potentially facilitates long-range interactions by providing a common temporal reference frame. FEF/V4

51
Q

Attention Signature: Decreased response variability

A

increases reliability of encoded information

V4

52
Q

Attention Signature: decreased low frequency synchrony

A

potentially reduces output redundancy by decreasing correlation

V4

53
Q

Attention Signature: decreased correlated noise at low freqs

A

potentially increases the sensitivity of pooled responses

V4

54
Q

Attention Signature: receptive field shift

A

potentially increases output signal by recruitng neurons

MT, V4

55
Q

Gaze + visual attention

A

gaze shifts occur in conjunction w/ shifts of visual attention.

premotor theory of attention. sigs of attention and saccades ahre a lot of similarities. mechanism responsible for spatial attention and the mechanisms involved in programming saccades are the same, but that in the covert case, the eyes are blocked at a certain peripheral stage

56
Q

How is spatial attention directed experimentally?

A

by stimulating FEF ( a ocularmotor area in PFC that is reciprocally connected to posterior visual areas)

57
Q

Spike collision

A
58
Q

what is the most prominent characteristic of FEF neurons projecting to V4?

A

Persistent activity during the delay period

59
Q

what is a decision?

A

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

can be thought of as a form of statistical inference

Active process

60
Q

what is an affordance?

A

how we perceive environment as ways to afford us our needs.
“What might I do w/ this stimulus in this context”

61
Q

which brain regions perform computations on sensory information in order to flexibly and adaptively control behavior?

A

PFC & parietal & insula & MTL

62
Q

Dorsolateral PFC

A

action selection

63
Q

orbitofrontal PFC

A

valuation

64
Q

ventrolateral PFC

A

speech planning & action suppression

65
Q

ventromedial PFC

A

choice selection & flexibility

66
Q

Anterior Coingulate Cortex

A

motivation, affect, conflict monitoring, pain, anxiety, everything

67
Q

How can PFC neurons handle all of these computaitons?

A

Mixed-selectivity. high dimensionality allows for differences in classifying things

68
Q

how has decision making been studied to date?

A

Tasks – largely based by response modality

random dot motion in a receptive field. results in speed-accuracy tradeoff

drift diffusion modeling – signal detection theory

69
Q

perceptual decision making

A

causal dissection of visual decision making circuit.

DV in LIP: small effect on choice, modest effect on reaction time, not equivalent to added rightward motion. stim adds constant

Momentary evidence in MT: stim adds cumulatively. relatively large effect on choice and RT. equivalent to added rightward motion

70
Q

PFC has been reported to show what?

A

orientation selectivity as well as encoding changes of mind!

71
Q

System 2

A

suppression of prepotent or disadvantageous responses

flexible allocations of cognitive resources

often in the face of conflict sensorymotor incongruence

1) conflict and error monitoring
2) post-outcome adjustment

72
Q

Cognitive Control

A

frontal midline theta.
is a process of expected outcomes

73
Q

Gratton effect

A

post-outcome adjustment

these are the experiments where the numbers were in the wrong place or the color of the word and the word is a color but they don’t match.

mediated in ACC

74
Q

which neuropeptide affects reinforcement learning?

A

Dopamine!

75
Q

among other things, dopaminergic VTA/NAcc neurons predict?

A

prediction errors!

76
Q

Q learning equaitons

A

V(t) = V(t-1) + alpha*delta(t)
delta(t) = R(t) - V(t-1)

V: reward prediction // expectation
delta: reward prediction error // ‘suprise’
R: actual reward
alpha: learning rate, can be from zero to one

77
Q

SARSA

A

state, action, response, state action
Q(s,a) = Q(s,a) + alpha*[R-Q(s,a)]

advantageous because it can incorporate a distribution of possible events

78
Q

when does disributional learning work particularly well?

A

on risky tasks! because landscape of infrequent failures are represented

79
Q

is there evidence of distributional learning in neurons?

A

Yes! optimistic and pessimistic neurons that match distributional temporal difference learning in vivo! Found in primate ACC

80
Q

Predictive encoding

A

error between neuron representation and the external world are progressively reduced through the cortical hierarchy

81
Q

general framework of predicitive coding

A
82
Q

active inference

A

minimizing free energy. action and perception become a joint optimization problem

83
Q

disease phenotypes of predicitve encoding?

A

yes, responsible for halluciantions in SCZ patients

84
Q

what is social neuroscience?

A

Cognitive social neuroscience/psychology
* social interactions, agency, empathy, morality, social prejudice and affiliations, individual biases, cooperation, etc.
* E.g. what makes us social, how we navigate our social world, how we think about ourselves and others in a social context

Neurobiology of social behavior
* any communication or interaction of two members of a species
* cooperative or competitive, these have been selected for through evolution to increase our chances of survival and reproductive fitness
* E.g. mating, fighting, parental behavior, bonding, interacting, sociality (social group living), altruistic behavior, affiliative
behavior, altruism (?)

85
Q

Unique qualities of social behavior

A

1) complexity communication avenues/communication via multiple modalities (e.g. USVs, body language, olfactory cues, before a fight, etc).

2) sensory cues that are specific or unique to social behaviors (e.g. pheromones for mating, maternal olfactory cues after childbirth, etc).

3) dynamic information from a conspecific that is also making its own decisions simultaneously, i.e. behavior of one animal depends on/is altered by behavior of the other animal (e.g. males and females during mating)

4) modulation by changes in internal state, resulting from past social experiences (i.e., sensory social cues remain the same, but your state may have been altered due to prior experience, e.g. attack behavior responses if you were/weren’t bullied

86
Q

Social behaviors are _____, _____

A

dynamic (depend on 2 animals)
modulated by internal states

87
Q

Tell me about social circuits in the brain

A

distinct but overlapping. mating aggression studies (ESR1a+). Circuits are hard-wired but do maintain some degree of plasticity

88
Q

what role does social history play upon behavior?

A

Social history impacts social behavior
and circuits
* Rank/Social hierarchy
* Housing history/isolation
* Early care
Padilla-Coreano
(U Florida)

89
Q

New tech for social neuroscience

A

Future challenges for descriptive models of behavior.
* Performance
* Generalization
* Interpretability
* Long timescales
* Level of Granularity
* Interacting agents

Systems Neuroscience (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions