Changes in the Brain Flashcards

1
Q

What are the building blocks of the Central Nervous System?

A

Neurons

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

What are neurons?

A

Cells that are responsible for receiving and transmitting electrochemical information

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

What are dendrites doing?

A

Receiving information from other neurons and sensory receptors

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

What is the axon doing?

A

It carries neuron’s messages to the other body cells

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

What do the terminal buttons of the axon do?

A

They form junctions with other cells and release chemicals called neurotransmitters

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

What does the cell body do?

A

It receives information from dendrites and if enough stimulation is received, the message is passed to the axon

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

What does the myelin sheath do?

A

It covers the axon of some neurons to insulate and help speed neural impulses

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

What is the grey matter in the brain?

A

Grey matter consists of neuronal cell bodies and their dendrites

  • Unmyelinated - cell bodies and dendrites
  • This is where information processing happens! Sensation, perception, voluntary movement, learning, speech, cognition, etc…
  • The cell bodies are responsible for our unique ability to think and reason
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What percentage of the brain is grey matter?

A

40%

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

What is the white matter in the brain?

A

Consists of the long axons of neurons that transmit impulses to more distant regions of your brain and spinal cord.

  • White matter’s role is to provide communication between different grey matter areas and between grey matter and the rest of your body.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What percentage of the brain is white matter?

A

60%

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

What is it called when a neuron is at rest?

A

The resting potential

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

What happens during resting potential?

A

sodium (Na+)is more highly concentrated outside the cell in the extracellular fluid, whereas potassium (K+)is more highly concentrated inside the cell. Other molecules, such as chloride (Cl-) and other negatively charged proteins (-) (brown squares), contribute to a positive net charge in the extracellular fluid and a negative net charge in the intracellular fluid

  • negative charge within the cell, positive outside the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is an action potential?

A

a neural impulse that carries information along the axon of a neuron)

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

What happens during an action potential?

A

During the action potential, the electrical charge across the membrane changes dramatically (depolarization), such that the inside of the cell becomes + charged

This results in the release of chemicals that serve to communicate with surrounding cells

  • The cell goes from a negative charge to positive because the cell membrane was disrupted
  • The cell wants to go back to its negative net charge and will do things to get rid of the positive chemicals and this is what the action potential is
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does neural communication occur?

A

Between neurons, communication occurs through transmission of neural information across a synapse by neurotransmitters

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

What is a synapse?

A

The space that exists where communication between cells can occur

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

How do neurotransmitters act like lock and key?

A
  • Receptors and neurotransmitters act like a lock-and-key system.
  • Just as it takes the right key to open a specific lock, a neurotransmitter (the key) will only bind to a specific receptor (the lock)
  • If the neurotransmitter is able to work on the receptor site, it triggers “changes“ in the receiving cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are some of the basic neurotransmitters?

A
  • Acetylcholine
  • Dopamine
  • GABA
  • Glutamate
  • Glycine
  • Norepinephrine
  • Serotonin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is dopamine?

A

The neurotransmitters that produces feelings of pleasure when released by the brain reward system.

Dopamine usually has multiple functions depending on where in the brain it acts.

It is usually inhibitory.

  • Highest as a teenagers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is serotonin?

A

A neurotransmitter involved in many functions including mood, appetite, and sensory perception.

In the spinal cord, serotonin is inhibitory in pain pathways

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

True or False: The effects of neurotransmitters are simple

A

FALSE.

They are compliated

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

What determines if an action potential occurs or not?

A

Receiving neurons receive multiple messages from other neurons. These multiple messages then determine if an action potential occurs or not.

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

True or False: The basic structure of the brain has been laid out during prenatal development

A

TRUE

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

What can looking at the brain tell us?

A
  • Some axons can connect to individual neurons more than a dozen times, while some connect only once
  • These multiple connections could indicate memories or skills that have been “strengthened” by repeated use
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Just something to know

A

Note how the axon terminals of sending neurons almost completely cover the cell body of the receiving neuron (these axons come from MANY different neurons!)

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

Why aren’t adolescent brains like adult brains?

A

it will take years of “fine tuning” before the brain functions in the same way as an adult and has adult-like microstructure

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

What is synaptogenesis?

A

Once in place, neurons start to make connections
Send out projections to nearby neurons
Rapid period of synapse formation begins, contributing in part to growth of grey matter

  • the creation of synapses
  • you create a lot of synapses but you don’t need all of them
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How can the brain be made more efficient with grey matter changes?

A
  • Cortical thickness decreases (because synapses are decreasing)
  • Synapses rearranged and pruned
  • Greater efficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

True or False: Young children’s brain work harder and less efficiently than adults

A

TRUE

  • Having all those synapses is expensive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How can the brain be made more efficient with white matter changes?

A
  • Myelination increases
  • Greater connectivity
  • Greater efficiency
  • White matter increases, not as many synapses, but these synapses have better communication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How does the brain figure out which synapses to prune?

A

Active synapses likely take up neurotrophic factor that maintains the synapse
Inactive synapses get too little neurotrophic factor to remain stable

  • Use it or lose it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are neurotrophic factors?

A

a family of proteins produced by the CNS that facilitate cell functioning

32
Q

What are some synaptic changes across development?

A
  • It’s not only the total number of synapses that are changing – it’s also the density of synapses that is changing!
  • This contributes to a thinner cortex but a more efficient one because the synapses are where they are needed and NOT where they are not needed!
33
Q

What are some of the pre-to-post adolescent brain changes?

A

Most brain regions undergo very substantial changes during adolescence; particularly in cortical regions, including the parietal, temporal, and frontal lobes

34
Q

What is the definition of synaptic pruning?

A

reflected in the thinning of the cortex

35
Q

What is the definition of myelination?

A

reflected in increases in white matter

36
Q

What does all that pruning and myelination accomplish?

A
  • Not much in terms of structure, since child and adult brains are organized generally in the same way
  • But A LOT in terms of activity, child brains show more diffuse, less focused activation
  • Overall, early in life there tends to be higher connectivity in adjacent regions, which transitions to stronger long range connections in adulthood
37
Q

What are some MRI techniques?

A
  • Structural magnetic resonance imagine (sMRI)
  • Functional magnetic resonance imaging (fMRI)
  • Diffusion tensor imaging (DTI)
38
Q

What is an sMRI?

A

A technique used to produce images of the brains’ structure

  • seeing the structure of the brain, the white matter, the tissues - tells us nothing about how the brain is functioning
39
Q

What is a fMRI?

A

A technique used to produce images of the brain, overlaid with images measuring activity in the brain (typically, oxygen) while the subject is performing some sort of mental task

  • can show which area of the brain is activated during a certain part
40
Q

What is DTI?

A

A technique used to produce images of the brain that shows connections among different regions (white matter tracts)

  • structure is involved here, we evaluate how water is flowing through the brain, evaluate clusters of white matter
41
Q

What is definition of plasticity?

A

The capacity of the brain to “change” in response to experience

42
Q

Is development of synapses determined genetically or environmentally?

A

Development of synapses in general is largely genetically determined BUT which synapses are strengthened and which are eliminated is largely due to the environment

43
Q

What is the developmental plasticity?

A

Extensive remodeling of the brain’s circuitry in response to experiences during childhood and adolescence, while the brain is still maturing.

44
Q

What is adult plasticity?

A

Relatively minor changes in brain circuits as a result of experiences during adulthood, after the brain has matured.

45
Q

True or False: A brain with plasticity learns new skills and languages more easily

A

TRUE

46
Q

When is the most pronounced period of plasticity?

A

Early childhood

  • the first 2-3 years of life
47
Q

What is the age of opportunity?

A

Adolescence is a second period of high plasticity

  • It’s a period that reflects an opportunity for dramatic change
  • Changes can be for the “better” or for the “worse”…
48
Q

Does maturation of the brain occur at the same time across the entire brain?

A

Maturation is does not occur at the same time across the entire brain

49
Q

What are white matter tracts?

A

(bundles of axons traveling between regions of the brain)

50
Q

What are the 3 domanis where adolescents see the most meaningful changes in brain structure and brain function?

A
  • Limbic System
  • The Prefrontal Cortex
  • The Social Brain
51
Q

Where is the limbic system?

A

Comprises several regions of the midbrain

  • Inside out the movie
52
Q

What does the limbic system play a critical role in?

A

Plays a critical role in the processing of emotional experience, social information, and reward and punishment

53
Q

What does developmental changes in the limbic system lead to?

A

Developmental changes leads to changes in the way we process emotional information

54
Q

Where is the prefrontal cortex?

A

A big segment of the frontal lobe

55
Q

What is the prefrontal cortex important for?

A

The region of the brain most important for sophisticated thinking abilities, such as planning, thinking ahead, weighing risks and rewards, and controlling impulses

56
Q

What does developmental changes in the prefrontal cortex lead to?

A

Developmental changes leads to an increase in cognitive capacities

  • Likely developed last from an evolutionary standpoint
57
Q

True of False: the proliferation and pruning of cells change brain structure

A

True

57
Q

What are two of the most important changes in the brain during adolescence (because of the developmental of the PFC)?

A

Activity within the PFC becomes much more focused resulting in improvements in two critical areas:

  • Response inhibition
  • Executive function

AND

Activity in the PFC becomes increasingly coordinated with activity in other parts of the brain (I.e. Its functional connectivity increases)

58
Q

What is response inhibition?

A

The suppression of behavior that is inappropriate or no longer required

59
Q

What is executive funcitoning?

A

More advanced thinking abilities, enabled chiefly by the maturation of the prefrontal cortex, especially in early adolescence

60
Q

True or False: the limbic system and the PFC develop in sync with one another

A

FALSE.

They do not develop in sync with one another

61
Q

What is adolescent risk-taking?

A

One of the major drawbacks of this difference in the trajectory of development is the propensity for our “emotions” (Limbic) to overtake “common sense” (PFC)

  • Imbalance between emotion-driven behavior, and behavior control
  • Just thinking about the immediate pay off and not the consequences
62
Q

What are the main health problems of adolescence that are the result of which behaviors?

A

substance abuse
reckless driving
unprotected sex

63
Q

True or False: Adults take more risks than adolescents?

A

FALSE

Adolescents take more risks

64
Q

What are some of the percentages of risky behaviors with adolescents?

A
  • > 40% of teen drivers report having texted while driving
  • 20% report riding with an intoxicated driver
  • 10% report that they have driven after drinking
65
Q

What is dopamine?

A

A neurotransmitter that is especially important for regulating the experience of reward

66
Q

Do adolescents become more or less sensitive to dopamine?

A

More sensitive

67
Q

What is serotonin?

A

A neurotransmitter that is especially important for regulating moods

68
Q

Do adolescents become more or less sensitive to serotonin?

A

Less sensitive

69
Q

True or False: Level of dopamine and serotonin decrease in adolescence?

A

TRUE,

They decrease

70
Q

What does a sensitivity to dopamine increase?

A

Sensation seeking

71
Q

What does a sensitivity to serotonin decrease?

A

Emotion regulation

72
Q

The increase in dopamine and decrease in serotonin make adolescents more?

A
  • Emotional
  • Sensitive to stress
  • Motivated by rewards (especially immediate rewards)
73
Q

What are other factors that can cause adolescents to engage in more risky behavior?

A
  • Lack of experience
  • More likely to “ go with their gut”
  • Sometimes we all do things that defy logic
  • Peer Influence!!
74
Q

Why does most mammals become more social around the time of puberty?

A

Probably because of sexual maturation

75
Q

What changes can you see from adolescents in their perceptions and behaviors?

A
  • More sensitivity to facial expressions and social cues
    Increased sensitivity to social evaluation
  • More susceptible to peer pressure
  • There is variance in sensitivity to the influence of others though! Adolescents are quite capable of ignoring demands if those demands interfere with their goals
76
Q

The development of the social brain may lead to what?

A

Development leads to an increase in sensitivity to social information and changes in the way social information is processed

Its development during adolescence likely contributes to feelings of self-consciousness

77
Q

Is the rate of basic cognitive and social cognitive development the same?

A

No, they develop differently

  • intellectually first
78
Q

At what age does intellectual capacity reach adult levels compares to psychosocial capacity?

A

Intellectual capacity reaches adult levels long before psychosocial capacity does (~ age 15 vs. ~ age 23!)

  • You’re smart before you’re socially confident