Lecture 3: The teenage brain

Question 1

adolescence start

Answer 1

differs per person, it starts with puberty. it can start around 10-14, not tied to a specific age, but more to a set of biological changes.

puberty: biological marker
- pubertal hormones
- growth spurt
- circadian rythym (Before puberty, your body makes you sleepy around 8:00 or 9:00 pm. When puberty begins, this rhythm shifts a couple hours later. Now, your body tells you to go to sleep around 10:00 or 11:00 pm.)

Question 2

end of puberty/adulthood =

Answer 2

less clear defined in biology, this is more cultural (drinking, driving, legal system)

Question 3

typical behaviour in adolescence

Answer 3

risky/impulsive behaviour: 200% increase in mortality rates (car crashes, binge drinking, unprotected sex, crime, substance use)

Question 4

mental health in adolescence

Answer 4

onset of a lot of psychiatric disorders, as well as drops in life satisfaction (after 20 it stays at that level, only increases at 60-70)

Question 5

even kijken naar grafieken in schrift life satisfaction, onset en complex moral reasoning development

Answer 5

ok

Question 6

hoofdproces tijdens adolescentie

Answer 6

social reorientation:
- shift from parents to peers (easily embarrassed by parents and annoyed) -> you have to find your way between standing out and fitting in.
- different relationships with peers: the time you experience with romantic partners.
- transition to more advanced moral reasoning and increasing prosocial behaviours.

complex: more risky behaviour + social re-orientation + onset affective and clinical disorders

Question 7

For a long time, it was thought that the brain was mostly developed at age 10,
when it was at adult size. but not true

Answer 7

oke

Question 8

grey matter en white matter =

Answer 8

grey = nucleus/cell body, cortical thickness
white matter = myelin on axons, structural connectivity

Question 9

grey matter brain development

Answer 9

use it or lose it!
1) synaptogenesis: after birth the neurons are in place, but still make many new connections
2) pruning: many of these new synapses will be eliminated -> experience based fine tuning of functional networks. this makes the network more efficient!

grey matter development happens first in the motor area, and higher cognitive functions develop later (PFC)

seeing/hearing - language - speech - higher cognition

Question 10

myelination, waarom?

Answer 10

Myelin increases the speed of the axon potential traveling down the axon, up to 100 fold compared to neurons that have no myelin

Question 11

development of myelin

Answer 11

here also first the more basic areas, later on the more complex ones (similar regional differences in development of white matter pathways). but in the pfc it remains increasing

myelination is relatiively experience-independent!

Question 12

prefrontal cortex shows the longest development

Answer 12

oke

Question 13

pubertal hormones

Answer 13

pass the blood-brain-barriere, impact dopamine (affective processing) and oxytocin (social motivation) in the brain

Question 14

social environment impacts brain development

Answer 14

neurons have larger dendrites when they are in an enriched condition (tested with rats in boxed)

less SES leads to less grey matter -> thinner anterior cingulate cortex, amygdala, striatum, hippocampus

Question 15

social brain hypothesis

Answer 15

bigger relative size of the neocortex xorrelates with the size of the social group (largeer groups is larger brains!)

Question 16

social information processing network: multiple systems

Answer 16

1. cognitive control/self-regulation: PFC, latral parietal cortex, anterior cingulate cortex
2. valuation/emotion/affect: amygdala, ventral striatum, ventro-medial PFC
3. social cognition (take perspective, reflect): posterior STS, temporal parietal junction, medial PFC

Question 17

what happens in adolescence according to the social information processing network

Answer 17

• initially the valuation system gets sensitive, and the control system is linearly catching up.
• the social orientation shifts from thinking about how others think of you in adolescence (MPFC) versus how you think about yourself in adulthood (TPJ)

sensitive period for social-affective processing

Question 18

adolescence: more emotion than regulation

Answer 18

okee oke

Question 19

dual system model

Answer 19

motivational limbic system (hot) vs. prefrontal control system (cool)

zie schrift

Question 20

triadic model

Answer 20

PFC -> ventral striatum and amygdala

zie schrift

Question 21

reward sensitivity

Answer 21

more activity in the brain when you win something vs. when you lose. this responsivity to rewards increases during adolescence and decreases afterwards

Question 22

emotional control: go/no go task.

Answer 22

go bij neutral faces, dont go bij lachen.

teenagers make more mistakes with happy faces.

ventral striatum shows a peak in reactivity -> happy face is rewarding. with scared faces we see more activity as well in amygdala.

-> stronger emotional responses = less control (more mistakes)

Question 23

embarassment study

Answer 23

self-reported embarrassment peaks in adolescence

when a camera is focused on you -> more embarassment in adolescents. MRI scanner show increases MPFC -> increased self-directed thought.

early adolescence: increased self-directed thought and embarrasment

Question 24

social evaluation task

Answer 24

the predicted acceptance from others decreases during adolescence, at 13-14 even below 50/50.

Question 25

social evaluation task: cyberball

Answer 25

online game, toss a ball. eventually you are excluded from the bot -> social exclusion. only adolescents show a significant decrease in mood after this ostracism. mPFC is activated again (social brain region)

Question 26

... activity in the mpfc predicts ... resistance to peers

Answer 26

more activity in the mpfc predicts less resistance to peers this relationship is not present in adults

Question 27

the more adolescents you put in a car, the more likely there is an accident

Answer 27

adolescents taking risks often happens in the presence of peers

Question 28

stoplight game

Answer 28

drive on a road, try to get there as fast as possible. stop for light. if you take a risk you could get into an accident -> if peers play together, more risky and more crashes. bij adults juist minder kans op crashes als er peers bij zijn. -> ventral striatum activity increases (maybe more rewarding?) -> balance impulse control is then shifted

Question 29

... activity in the striatum means .... resistant to peer influences

Answer 29

more activity in the striatum means less resistant to peer influences

Question 30

body image paradigm

Answer 30

judge whether the shown body would be considered normal or not normal. later they would see what others said about that. if there was a prediction error, people with low self esteem would correlate with more activity in the right insula (processing internal feelings, especially discomfort, uncertainty, and self-awareness) -> So, when someone with low self-esteem realizes they disagreed with others (i.e., made a "mistake"), their brain shows heightened sensitivity in that area. This might reflect feeling anxious, judged, or self-conscious. -> low self esteem is more sensitive to social disagreement

Question 31

instagram paradigm

Answer 31

teens could just like whatever they wanted. - amount of likes: more likely to like a photo - normal vs. risky behaviour: Adolescents were more likely to like a photo, even one portraying risky behaviors, such as smoking marijuana or drinking alcohol, if that photo had received more likes from peers.

Question 32

prosocial behaviour=

Answer 32

actions, such as sharing, helping, or comforting, that are intended to benefit other people

Question 33

if they know a peer is a risk taker...

Answer 33

they will show more risk taking behavior. if they know a peer is not a risk taker, they will not

Question 34

3 things that lead to increased prosocial behaviour

Answer 34

- increased empathic concern - advanced perspective taking (meer cognitief) - cognitive control (need to regulate/suppress impulses to be nice)

Question 35

pain matrix is activated when...

Answer 35

- experiencing pain - observing other in pain - when harm is intentionally inflicted: also social brain regions -> PAG, SMA, aMCC

Question 36

pain matrix differences adolescents and adults

Answer 36

* Adolescents show more activation in the affective brain regions * Adults show more activity in the prefrontal regulatory brain regions. -> adults are better at down-regulating their emotional responses (better for helping someone)

Question 37

social perspective taking

Answer 37

the ability to infer others' thoughts, intentions, motives and attitudes

Question 38

role taking=

Answer 38

the ability to assume another persons perspective and understand their intentions, thoughts, feelings and behaviour

Question 39

selmans five levels of perspective taking

Answer 39

0. egocentric or undifferentiated perspective (3-6 yrs) 1. social-informational role taking (6-8 yrs) 2. self-reflective role taking (8-10 yrs) 3. mutual role taking (10-12 yrs) 4. societal role taking (12-15 yrs and older)

Question 40

ultimatum game

Answer 40

proposer makes a proposal to the responder about how they will divide 10 euros. responder can accept or decline

Question 41

inequity aversion

Answer 41

the more the equality of the offer declines, the more people will reject the offer. they rather have nothing! they therefore also think about others. this relativity is also present in monkeys: give one a cucumber and the other raisins: they will get mad. -> requires perspective taking.

Question 42

the role of intentions

Answer 42

compare when there is a fair alternative, versus when there is not. - kids still reject the unfair alternative, even when the other person had no choice - adults reject these offers less when they know the other person had no choice -> intentions become more important with age

Question 43

waar zie je perspective taking in the brain

Answer 43

TPJ activity (temporoparietal junction), increases with age. Brain activity TPJ mediates age related changes in rejection rates. -> suggests that perspective-taking indeed plays a crucial role in changes in behavior

Question 44

DLPFC activity increases as well, showing...

Answer 44

more regulation

Question 45

social reinforcement learning

Answer 45

- 3 kids faces with different rates (continuous, frequent, rare) - press the button when you see a face. if you do it within 2 seconds you get positiv or negative feedback. - you have to learn who is nice and who is not nice

Question 46

formule betekenis van de dingen

Answer 46

V is expectation of positive feedback. (between 0-100%) V t+1 is the expectation on the next trial (after receiving feedback) delta is the prediction error (what did I expect – what did I get) a is the learning rate (how much do I change my expectations). V predicts Reaction Times to stimulus, faster for higher V

Question 47

resultaten van die formule: social reinforcement learning

Answer 47

- vaak 2 verschillende learning rates voor positief en negatieve dingen - voor negatieve dingen zijn mensen meer gevoelig: change beliefs more - the higher the V, the higher the response time - Adolescents don’t really change their beliefs after positive feedback! (a is low, deelta is activated when there is a prediction error) -> may be because they dont really belief that others like them -> are more sceptical -> do less with positive feedback

Question 48

Putamen active when receiving positive social feed-back regardless of the expected outcome. Graph suggesting that peer approval may motivate adolescents toward action (but not change in beliefs!).

Answer 48

oke

Question 49

emotional go/no go task

Answer 49

Adolescents show: Increased amygdala activity to emotional faces, especially threatening (e.g., angry faces). Less effective recruitment of the ventromedial PFC (vmPFC) and lateral PFC during inhibitory control, especially in emotionally charged situations. In emotionally neutral contexts, inhibitory control improves — suggesting emotional input disrupts control. The Dual Systems Model would attribute adolescent impulsivity mostly to: Overactive limbic response (e.g., amygdala), Underdeveloped PFC control. BUT: The Emotional Go/No-Go study shows something more nuanced: The amygdala (emotion system) is hyperactive. The vmPFC (interface between emotion and control) fails to regulate amygdala activity effectively. This isn't just an issue of "strong emotion vs. weak control" — it’s about interaction failure among three components: Amygdala: detects emotional salience. vmPFC: integrates emotional input and modulates control. lateral PFC: executes cognitive control (inhibition). This tripartite dynamic fits the Triadic Model better.