ECB 2 Lecture 1

Adolescence

• Phase distinct from childhood and adulthood – universal

• Onset and end – culturally specific

• Onset: puberty

• End: achieving full adult roles

Mortality in adolescents

• Increase in age through risk taking behavior → unintentional injuries (traffic accidents)

• Especially in boys

Mental health in Western adolescents (11-19)

• Mental disorders tend to begin in youth (less chance of having mental disorders in adulthood if you do not have them in adolescence)

• Episodes of mild DSM-IV mental disorder are common

• 22% of the adolescents experienced at least one severe disorder; 10% had poor mental health

• The prevalence of severe mental disorder in adolescents is higher than even the most prevalent major somatic conditions

• Major risks but still major opportunities in adolescence

Start of adolescnece: Puberty

• Start with bodily changes triggered by hormones → Gonadotropin-releasing hormone

• This increases luteinizing hormone and follicle stimulating hormone

• These hormones trigger the rise of testosteron in boys and estradiol and progesterone in girls

End of adolescence: Adult role

• End of adolescence when you take on adult roles → can be culturally specific

• Usually richer adolescence take on adult roles later → longer adolescence

• Longer duration of adolescence → longer period of risks and opportunities

Puberty and the brain

• Long-term process

• Hormones influence how the brain is organized (e.g., testosterone leads to increase in grey matter in medial amygdala)

• Hormones influence the way that brain cells become activated in response to a situation or environment (e.g., testosterone increases during a fight; mice who win a fight develop more receptors for testosterone in brain regions that are important for reward and social behavior)

Structural brain changes during adolescence

• Gray matter tends to thin

• White matter increases in volume

• Functional connectivity changes

• Neurons/synapses first proliferate, and then are pruned

• More than 40% of synapses are eliminated

• Changes in frontal/basal ganglia circuits

Functional brain changes during adolescence

• Cognitive control: both increases and decreases in prefrontal activation during adolescence; increases in parietal cortex

• Affective processing: nonlinear pattern with peak in subcortical processing in mid-adolescence

• Social-cognitive processing: gradual increase in TPJ, gradual decrease in dmPFC (anterior-posterior shift) from adolescence to adulthood

• Social-affective processing: increased response to acceptance and rejection

Dual process models

• Mismatch between increased sensitivity to emotional stimuli in limbic areas and delayed maturation of cognitive control

Individual differences influencing adolescence

• Genetic and environmental factors

• Neurocognitive development

• Mental health

Social cognition

• Face / emotion recognition

• Empathy

• Perspective-taking / theory of mind

• Social decision-making (trust)

Face recognition in adolescence

• Face perception (identity) and face memory improve during adolescence

• Female > male in face memory but not perception

• Compared to adults, looking at emotional (fearful) faces elicits more brain activity, which is less influenced by top-down control

Development of empathy

• Increases in adolescence

• Advantage in females (at least to self-report)

Perspective-taking during adolescence

• Increases in adolescence

• Even adults have problems with it → depends on cognitive effort

Development of trust in adolescence

• The trust game: willingness to invest money depends on trust that the other will return (some)

• Trust increases over adolescence and life (incline again later in adulthood)

• You become more trustworthy over life

• Increasing ability to distinguish between social and selfish partners (van den Bos et al, 2010)

• Increasing ability to integrate partner’s responses with a priori information (Lee et al, 2016)

Social cognitive development: Summary

• Basic skills are in place before adolescence

• Face/emotion processing: dip in early adolescence; gradual increase in capacity to modulate emotion processing

• Self-reported empathy: gradual increase; gender difference (F>M)

• Perspective-taking: gradual increase in usage of other persons perspective

• Trust: gradual increase in use of both actual feedback and a priori information

Peer relations in adolescence

• Social evaluation

• Social influence

• Social exclusion

Sensitivity to social evaluation

• N=69

• fMRI, camera off, warming up or projecting image to a peer → peer watches you being scanned

• More self-reported embarrassment, arousal, mPFC activation, and striatum – mPFC connectivity in adolescents compared to children and adults

Adolescent risk taking

• Increase in young adolescences

• Increase when peers are watching

• No gender differences

Social influences and body image

• Norm-deviating feedback on ideal body image resulted in activity in ACC-insula network in young females (18-19 years)

• This effect was stronger for females with low self-esteem

• Rating was adjusted in the direction of group norm

Social rejection and the brain

• Measured using cyberball paradigm

• First included, then excluded from the game

• Reported exclusion-related distress

• Three age groups: young adolescent, mid adolescent, adult females

• Exclusion influences mood in YA and MA

• Exclusion triggers anxiety in YA

• Activation in insula and subACC related to self-reported distress

• Activation in subACC associated with increase in depressive symptoms (CBCL) at 1-year follow-up

• Sustained activation in dorsal ACC in youth with major depression - link to rumination?

Social rejection and the behavior

• Young adolescents predicted that they would be liked less frequently

• Young adults overestimated the extent to which they would be liked by peers

• Young adolescents felt worse about themselves after rejection

• Young adults preserved positive self-views

• Young adolescents maintained impressions of peers regardless of peer feedback

• Young adults updated impressions of peers based on whether that peer accepted or rejected them

• Adolescents more likely to expect and internalize negative judgments

• Adults use self-protective strategies:

  • Expect to be liked

  • Maintain positive self-view after rejection

  • Dislike source of negative feedback

• From the adolescent perspective, social risk may be more harmful than health and saftey risks