adolescence - social development

• definition of adolescence

  • one biological marker is the onset of menstruation in females
  • in males it is the time of first ejaculation
  • puberty occurs later for boys
  • puberty is brought on by hormonal changes
• are adolescents prone to risk taking

  • peak in risk taking is at grade 12 for drinking - age 17/18 years
• increase in risk taking in emergent adulthood

  • due to age-related developmental changes
  • more opportunities to be involved in risk taking
• brain areas involved in dual systems model

  socioemotional system

  • increase in dopaminergic activity modulates the function of the ventral striatum
  • the ventral striatum is involved in reward-seeking behaviour
• cognitive control system

  • involves the more slowly maturing pre-frontal cortex
  • responsible for planning judgement and inhibition
  • restrains emotional impulses
• are adolescents prone to risk taking?

  • adolescents take more risks than adults on tasks that involve immediate feedback on rewards and losses
  • supports dual system model
  • BUT mixed findings on whether there is increased activation in the ventral striatum compared with adults in reward and loss studies
• social development during adolescence

  • participants weight safer social information more strongly than risky information in adolescence
  • adolescents are motivated to avoid social rejection - drives decision making and behaviour
  • small to moderate correlations between social media use, general risk behaviours, substance use, risky sexual behaviours
• driving simulation study with peers. (chein et al) 1

  • participants offered money to drive round a track as quick as poss
  • when approaching an intersection they needed to push a button about whether to brake at yellow light or change a possible crash by not breaking
  • time lost if participants crashed
  • ALONE conditon
• driving simulation study with peers (chien et al) 1

  Peer condition, participant actions observed by two friends and communicated with participant via intercom whilst in fMRI scanner

  increase in risky decisions when observed by peers for adolescents only

  self-reported sensation seeking but not impulsivity for sample predicted risky decision making
• driving simulation study with peers (chien et al 2)

  • adolescents recruit the social emotional system in decision making
  • evidenced by greater activity in the ventral striatum compared with left lateral prefrontal cortex when adolescents were alone
• driving simulation study with peers (chein et al) 2

  adults recruit the cognitive control system in decision making

  • greater involvement of the left lateral prefrontal cortex in adults compared with adolescents
  • did not differ in the presence of peers
• social evaluation of risk taking

  • the relationship between perceived social benefit and expected involvement in risk behaviour, broken down by risk domain
• why do risk-taking behaviours increase during adolescence and early adulthood?

  • decreased adult supervision
  • more opportunities to interact with peers whose behaviour may be considered deviant
  • increased access to previously restricted activities such as driving, drinking and gambling
  • dual systems model doesn't account for exposure to risk taking
• adolescence and mental health

  • increase in OCD, eating disorders, anxiety
• adolescence and mental health

  • peak age for diagnosis for anxiety disorders is 5.5 years, lower peak at 15.5 years. median diagnosis age is 17 years
  • 73% of anxiety disorders had onset before age of 25
• what are some protective factors for good mental health in adolescence

  • screen time > 2 hours per day - lower life satisfaction and optimism, higher anxiety and depression
• proactive factors for good mental health in adolescence

  • participation in extracurricular activities (at least once per week)
  • lower depression scores but no difference in anxiety
  • greater optimism, greater life satisfaction
• longitudinal data on social media use and wellbeing

  • no significant relationship between high or low social media use and mental wellbeing or fear of negative evaluation
  • individuals with low mental wellbeing -> significantly greater fear of negative evaluation at age 10 which was stable through to age 25
  • subtle differences in brain anatomy between high and low social media users
• the social brain

  • medial prefrontal cortex and the temporoparietal junction, which are involved in thinking about mental states
• pSTS activated by observing faces and biological motion
• other regions include the inferior frontal gyrus (IFG) and the interparietal sulcus (IPS)
• adolescence and social jetlag

  • mid sleep time on free days adjusted for average sleep duration to account for recovery sleep at weekends
  • adolescents chronotype on average shifts later, with peak lateness at age 20 before their chronotypes become earlier again
  • adolescent bedtimes when unconstrained by other commitments shfit later and wake times are later
• adolescents have a sleep problem

  • about 42% of 19 year olds obtain 7 hours of sleep either every day or almost every day versus sometimes, rarely or never
• sleep and risk taking in adolescence

  • shorter sleep duration associated with increased risk taking
  • experimental study showed 14-15 year olds more risk decision making in a virtual environment as a pedestrian
• sleep and risk taking in adolescence

  in 4 hours sleep condition versus 8.5 hours sleep condition:

  • leaving less distance between themselves and a care and experiment more close calls or virtual hits
• changing the environment to meet sleep needs of adolescents

  • shifting secondary school start times from 7:10 to 8:20am in US sample
  • significantly later wake times and bedtimes and longer sleep duration by 45 minutes
  • reduced proportion of students driving whilst drowsy at least once a week - from 33% to 22%
  • at post intervention - 6 months reduced the proportion of students who reported always or almost always feel sad, nervous, feel worried and too tired to keep up with schoolw ork