Lecture 4 Flashcards
(28 cards)
1
Q
What is Adolescence?
A
- Period between sexual maturation and attainment of adult roles and responsibilities
- Begins in domain of biological changes with puberty and ends in domain of social roles
- Encompasses transition from status of child to adult
- From ages 10-20
2
Q
How are psychological changes linked to hormonal changes in puberty?
A
- Sexual interest changes
- Emotional intensity
- Sleep cycle changes
- Appetitive
- Disk for affective disorders
- Increase in risk-taking, sensation seeking, and novelty seeking
3
Q
What is the health paradox of adolescence?
A
- Physically healthiest period of life
- Improvements in strength, speed, reaction time, reasoning abilities, immune function
- Increased resistance to cold, heat, hunger, dehydration and injury
- BUT Morbidity rates increase 200% from childhood to late adolescence
4
Q
Why is there so much morbidity in the UK?
A
- Risk of young men dying is higher than women
- Increase in mortality in UK from 2014
- Deaths from assaults
- Higher risk is from accidents, and self-harm = related to emotions and behaviours, as well as onset of problems with later health consequences
5
Q
What are theories of cognitive development?
A
- Most basic information processing skills increase throughout childhood and early adolescence and level off at 15
- At 15, adolescents are just as proficient as adults in these basic cognitions
- But lack abilities to plan ahead, judge costs/benefits of risks, coordinate cognition and emotion when feelings interfere with logical reasoning
6
Q
How do brains grow?
A
- Brain has reached 90% of adult value by approx 7yo
- Little change is occurring in overall brain growth = might be dynamic changes in some tissues
- Over time, reduction in grey matter to make space and improve connections - white matter, starts in back of brain and finishes in pre-frontal cortex
- Decrease in grey matter via synaptic pruning, increase in connections among cortical areas as reflected by increase in white matter via myelination = associated with improved higher order functioning.
- Increase in connections between cortical and subcortical areas = improving coordination of affect and cognition
7
Q
What do the temporal and frontal lobes do?
A
- Limbic system regulates emotions and motivations, related to survival and pleasure
- Frontal cortex is for personality, judgement, reasoning etc. Governs impulses, aggression and ability to organise thoughts and plan for future
- PFC undergoes significant changes during adolescence and not fully developed until mid 20s
8
Q
What are other factors affect the brain during adolescence?
A
- Hormones
- Dopamine underlies incentive-reward motivation
- Pruning of serotonin circuits may lead to increased impulsivity (mood swings)
- Common maladaptive behaviours in adolescence also contribute to impaired judgement via substance use and less sleep
9
Q
What are the endocrine systems?
A
- HPA axis: regulates stress response and increase in stress
- HPG axis: sex hormones, regulates sexual maturation, increase mood fluctuations and sexual stimulation
10
Q
Why is there an imbalance in adolescence?
A
- Have this rapid increases in limbic system - rapid growth and changes, but cog capacity is weak, so biological drives are strong and difficult to control, self-control is weak
- Over time cog capacity increases and it reins in incentive driven behaviour.
11
Q
Why are brains programmed this way?
A
- Evolutionary: to live an independent life confidently separate from family
- Better for social influence etc. = make own friends, mates
12
Q
What is the model of development?
A
- Early ad: 10-14 = puberty heightens emotional arousability, sensation seeking, reward orientation = supervised by parents which becomes less and less
- Mid: 15-19 = -4 period of heightened vulnerability to risk taking, problems in affect and behaviour
- Late: 20 - 24 = maturation of brain facilitates regulatory competence
13
Q
What is the neurobiological model of adolescence development?
A
- Prefrontal cortex is slowly happening
- Nucleus accumbeas: earlier development for emotional limbic system
- Discrepancy between limbic system vs delayed PFC explains why there is a gap = why there is a problem with behaviour
- We all go through this process, but there are individual differences e.g size of discrepancy, or if PFC never develops
- Physically mature earlier = evidence that hormonal development happens earlier or more intensely so gap is larger
14
Q
What is the effect of dopamine, peers, and risk taking?
A
- Significant changes in density and distribution of DA receptors within regions critical for incentive processing
- Elevated salience and reward value of peer interaction
- fMRI regions activated during exposure to social stimuli overlap with regions sensitive to non-social reward
- Peers make potentially rewarding and risky activities even more rewarding
- Peeks around 15 and then begins to decline
15
Q
What was a study looking at risk and reward?
A
- Ppt was sitting in virtual car and had to drive as fast as possible, but they would be randomly confronted with a stop signal, the most sensible would be to stop and wait which would result in a 3s delay, if you ignored and got hit by the train it was a 6s delay
- Had adolescents, young adults, and adults, as well as doing it alone or with a peer
- Alone = adolescents did not take more risky decisions and did not have more crashes, only when there was a peer watching them, risk taking and number of crashing increased significantly, but not in others groups
- Shows peers are rewarded activity
- In the scanner, the risk taking had more reward activation going on in the brain
16
Q
What was a study looking at decision making in children and adolescents?
A
- Cross-sectional study comparing general cognitive executive functioning and affective decision making in 8-17yo
- Standard EF tests were significantly positively correlated with age, indicating that cool cognitive skills improve linearly with age
- IGT performance followed a quadratic regression curve supporting that younger participants failed to show a preference for either deck, those at 10-13 make consistent disadvantageous choices, improvement at 14 and peak performance at 17
- Adolescent’s greater involvement in risk taking is not from ignorance, irrationality or faulty calculations
- Factors that lead risky behaviour are social and emotional
17
Q
What are some adolescent problem behaviours?
A
- Teen pregnancy
- Violence
- Delinquency
- Substance abuse
18
Q
What is the role of early abuse?
A
- Chronic stress sensitises neural pathways and over develops brain areas like the limbic region involved in fear/anxiety = under development in other regions like frontal lobe
- Chronic stress impacts psychological development on a cellular level
- Chronic HPA axis activation focuses the brain on survival and other areas of the brain get worn out for developing social, cognitive and regulatory skills
19
Q
What are sex differences in mental health prevalence? (Females)
A
- Females have a greater sensitivity to stress especially social/familial ones
- Early exposure to stress = early physical maturation = risk factor for adverse psych health = if env is unstable you want to pass on genes sooner than later
- Oestrogen fluctuations increase mood dysregulation and amplify stress response affecting risk of psychological problems
20
Q
What are some advantages of being female?
A
- Advanced language and verbal skills
- More effective processing of social and emotional cues
- Better emotion regulation, less acting out
- Dominant motivation is tend/befriend rather than fight/flight due to hormonal differences
- Female hormones protect against stress-induced cognitive impairments and cog decline due to aging
21
Q
What was a study looking at gender differences in HPA axis reactivity?
A
- Pronounced gender differences in prevalence of psychological disorders
- Non-human animal studies show higher stress levels in females than males
- Wanted to examine sex differences in stress response to different methods of HPA axis activation: psychological stressor and pharmacological challenge
- Ppts had a 5min public speaking followed by 5 min mental arithmetic, intravenous catheter, 8 blood samples, naloxone was administered at 30/60/90/120 min, IV catheter collected blood twice before challenge and then at 15 min intervals for 180 min
- Data for psychological stressor suggests that men are more sensitive
- Pharm stress: response seen with cortisol levels higher in women
- HPA activation helps explain gender differences in prevalence of diseases and depression
22
Q
What was a sex difference in stress responses?
A
- Sex differences in stress responses may be one mechanism underlying gender differences in depression
- Men and women will have different cortisol stress response: M: achievement stress, W: social rejection stress
- Had male stressor: mathematical and verbal challenge, Female: stage conversation and asked to discuss certain topics and excluded participant
- Negative moods went up when achievement did not go right, in rejection challenge = slight negative mood but no gender difference
- Achievement stressor was considered more negative by both genders
- Cortisol: during cog challenge go up in men but not much in women, different for social rejection challenge
23
Q
What were the results of sex differences in stress response?
A
- Women may not only use interpersonal strategies to cope with stress but also show greater physiological responses to interpersonal events
- Men and women found the stressors similarly stressful, suggesting that sec differences in psych stress may not be mediated by affect and perceptions of stress but reflect biological or implicit cognitive processes
24
Q
What are implications for preventions?
A
- Logical reasoning and basic info processing abilities of 16yo are comparable to those of adults
- Approach is to reduce risk-taking but effectiveness is doubted
- Adolescents are no worse at perceiving risks than adults or estimating their vulnerability to it
- Increase in risky behaviour is not due to ignorance
- Solution: change context of risky activities, mentors and role models to demonstrate good decisions
25
What are the issues with education-based interventions?
- Improves knowledge but rarely changes behaviour
- Adolescents are logical and perceive risks similarly to adults = not about cognition, but about social and emotional factors
26
What brain development studies provided insight to risk behaviour?
- Increased research on links between brain structure and risk-taking
- Just like hormone behaviour studies, context matters
- Risk-reward game in fmri scanner and had to observe activity in brain
- Found that adolescents show heightened activation in brain regions linked to reward sensitivity
- Prefrontal cortex was still maturing and showed less activity
- Brains are more sensitive to reward but worse with impulse control
27
What was a study looking at reward and brain regions?
- When adolescents were exposed to peer acceptance, there was greater activation in brain regions associated with reward salience
- These are the same brain regions activated by nonsocial rewards, like food or money.
- Social acceptance is processed similarly to other forms of reward
28
What is the reward salience and deficiency hypotheses?
- Adolescents seek more stimulation due to underactive dopamine systems
- Heightened dopamine sensitivity, not deficiency.
- Loss of dopamine autoreceptors reduces inhibition → more dopamine release = Leads to stronger reward salience and sensation-seeking
