Psych 161 Final

Accurate "reading" of facial expressions is very important early in life

'The accurate decoding of facial signals, particularly facial expressions, is absolutely fundamental in early interpersonal communication.' -infants are nonverbal so communicate with caregivers by reading their faces -good at identifying faces, distinguishing between basic emotions

Who is a juvenile?

'minors' include people 17 years old and under 'age of majority' in the juvenile justice system is 18 years old but rights and privileges in the U.S. vary by age:

However, when attention to emotional stimuli is equitable, ASD participants actually show greater amygdala activation

-ASD show greater activation in amygdala when processing emotions -before viewing images passively -explicitly told them to pay attention to emotions in this study which led to greater activation of amygdala in group with ASD -too much arousing information from eyes? -amygdala most active when feeling threatened, Perhaps decreased activation in social brain regions in ASD reflects lack of attention to emotional or face stimuli Increased amygdala activation might be reflective of greater threat sensitivity to emotional stimuli in ASD -participants all adolescents -programs that help young kids with autism will lead to more normal activation

Pubertal hormones are released in the brain

-From hypothalamus you get release of pubertal hormones -From hypothalamus you get release of pubertal hormones -pituitary gland important in puberty too, releases GnRH

Gonadotropin releasing hormone (GnRH) is the main hormone that jumpstarts puberty

-GnRH is important b/c other hormones released during puberty a -onnly job of GnRJ is to trigger puberty

Adolescence: A striking paradox

-able to incorporate new info -experimenting with drugs and alcohol -making unwise driving decisions -arguing with parents -but also activists -smarter than you ever will be but also dumber than you ever will be -differences in neural development of certain brain regions -1/2 of deaths of people of teenagers are unintentional injurys, mostly made up of motor vehicle accidents -teenage brain has emerged as a way to study why adolescents do what they do

Sleep is a basic need that suffers during adolescence

-adolescents: striking change in how much sleep people get, adolescents don't need 15 hours a day but need a lot to incorporate everything their learning, pubertal changes, shifts in social dynamics -our bodies rely on sleep -adults require about 7-9 hours per night More than 90% of teens are chronically sleep-deprived -decline in sleep recommendations -adolescents need 8-10 hours a night based on how much you need to perform optimally -over time has implications for relationships, ability to learn, etc. Bedtime gets later from early to late adolescence in the U.S. Rise times stay the same -as kids move from elemntary school -> high school, they go to bed later and later -getting older has more demands, hw -bigger interest in extracurriculars, being with friends -teenagers go to bed later, rise time stays the same -blue lines represent shrinking amount of time in bed

Brain changes can lead to both positive and negative outcomes

-all of these changes happneing in brain (pubertal onset -> many changes), these lead to positive and negative outcomes -most narratives about adolescents focus on negative outcomes, but the paper this figure is from emphasizes that positive things can come out of it too, maybe its good to take risks that will have good outcomes for you -ex. If all of us had too much regulation of PFC, it might have prevented you of taking risk of going to college -adaptive to have period of life that PFC isn't in control of anxiety so that you aren't inhibited to try new things, new majors, etc. -puts you in positive gorwth trajectory, encourages exploration, which leads to growth and new experineces helping you to mature

Monkeys with neonatal amygdala lesions produce odd social behaviors

-amygdala lesioned monkeys compared to control monkeys and hippocampus lesioned monkeys, showed odd social behavior, if you coo, grunt, or lipsmack too much that's not adhering to social rules, amygdala lesions, unable to stay in confines of social rules

American Academy of Pediatrics recommends school start time at 8:30am or later

-avg start time was way before 8:30am

Ability to recognize facial/emotional expression is not present until the age of 5-7 months

-before that time, infnats use other cues (e.g. voice) to discriminate facial expressions -7 months of age, infants more interested in fearful than happy.neutral/other faces Infants show less diengagement from an emotional (fearful) face when presented with a peripheral target (i.e. they stare longer at fearful faces) -usually you look towards flickering peripheral information, new information, if face in middle is fearful face, they show less disengagment from it as opposed to if middle picture is sad, happy or other face -only looked away at fearful face 50% of time, other faces looked away around 75% of time

Pubertal Implications on Behavior

-consequence of being off time in pubertal timing (not undergoing puberty at the same tiem as peers) Girls who mature earlier than her peers: More likely to smoke, drink; exhibit disordered eating; depressive symptoms, have lower self-esteem; be sexually promiscuous; experience conflict with parents, and have older friends -having older friends and starting to be sexually active -having older friends and starting to be sexually active -changes the way the world treats you, who you hang out with, expectations -negative psychological effect Boys who mature earlier than his peers: higher frequency of internalizing symptoms; depression, worry, fear, self-injury, and social withdrawal externalizing symptoms aggression, law-breaking, or hyperactivity -mixed reviews for boys -can gain popularity, -trying to gain respect of adults, they want to be adults but there is a gap Girls who mature later than her peers: More successful psychosocial, academic and other outcomes -benefits in maturation in girls later -girls maturing later is confounded with other activities like sports, challenging to disentangle

Is adolescence changing?

-examined behaviors across ppl in adolescent age range -14-18 years of age -1976-2014 -90% of adolescence in 70s had drivers license now its 75% -tried alcohol as dropped, work for pay has dropped greatly -ever dated has also dropped -what explains this? -maybe they have less time to get it together -we can now use uber to get around -not wanting to get tied up -suggested that uptake in technology is the answer -across many different subjects

Humans become 'human face specific' with age

-face detection ability: as you get older you get better able at detecting faces of own species (differentiating) -worse able at detecting faces of different species when you're older -reminds us of language: perceptual narrowing happening for language happens for faces too?

ERP study

-greater brain activity in infants in response to fearful faces -brain is making note of fearful faces, categorizing them

Faces are a rich source of social information

-immediate way to try to understand how someone else is feeling -is person happy or mad at me, or how that person is currently feeling -face has certain conigurations to display emotions, smiling -face has certain conigurations to display emotions, smiling -wide eye look of surprise is the same as fear -open teeth is part of anger and happy -raised eyebrows, widened eyes, flared nostril: surprise and fear, trying to gather more social information -fight or flight -we want to infer mental, emotional of someone else, but also want to gather info for your own safety -social information and warning signal for own safety

Rats will press a lever continuously to stimulate the "reward center"

-implanting electrode in reward center and passing electrical current is pleasureable -does this over and above getting water, food, sleeping, until exhaustion, death -insight on drugs Juvenile ("adolescent") rodents are more likely to exhibit reward-seeking behavior, increase social interactions, increased proclivity towards drugs and alcohol, than adult animals -will even walk across shocking cage to get reward -take more risks, more likely to be interested in drugs and alcohol

Testosterone levels start low in childhood, rise steeply in adolescence and then level off in adulthood

-increase in testosterone in both sexes, but significantly more in males, rises vary steeply around 10, in girls a little more gradual and tapers off quickly in females -lots of variability in individual data -not everyone shows the same avg data -some change very rapidly, there's variability among people in sex groups -some males don't have high testosterone even in adolescent years

How do humans become face and emotion experts? Face processing abilities emerges early in life

-is it innate -really good at detecting emotion -are we born with it and refine it or do we use brain regions developed for something else and appropriate them to survice or needs -face processing abilities emerges early in life: born with ability? -newborn see pic of face vs. image of plug -face experts very early on

Prosocial Task

-keep money or give money to family -hedonic decision give yourself 3 dollars -eudonomic decisions - give money to family -given psychological assessment about how depressed they were feeling -sometimes made hedonic decisions or eudonomic decisions -activations people showed were associated with depressive symptoms at time 2 Individuals with greater activation during hedonic decisions showed an increase in depressive symptoms over time Individuals with greater activation during prosocial (eudaimonic) decisions showed a decrease in depressive symptoms over time -people with more activation in striatum in eudonomic decisions showed less depressive symptoms over time -naturally less likely to experience depression -or giving behavior is a buffer to depressive symptoms -done just in adolescents but probably similar results in adults

Methods in Braams study on adolescent reward and risk-taking

-longitudinal study, followed up at time 2 2 years later -first time 1 (8-27 year olds) -both time points reported Self-reported pubertal development (PDS) -people aren't accurate with their info Self-reported risk-taking (BIS/BAS) Hormone levels (testosterone) fMRI reward task

Gonadotropin releasing hormone (GnRH)

-mapping development on X axis and GnRH levels on Y -prenatally some GnRH floating in brain b/c important for hormones, helps sexually diffinteriate some regions, males tend to have bigger aygdala, GnRH helps differentiate that size -postnatal and childhood - very little, almost none -at puberty very strong increase in GnRH levels b/c release happening in hypothalamus -after puberty in adulthood, go back down into nothing b/c no longer necessary, GnRH during menopause plays some sort of role but very little compared to puberty Re-emergence of GnRH section for reproductive behaviors -childhood -> Puberty = re-emergence of GnRH GnRH is an organiztional role in prenatal life -GnRH is an activational role around adolescence b/c activating puberty -GnRH released in hypothalamus, release of GnRH makes the same stimulus have a different meaning depending on your age GnRH changes the meaning of sensory information Adult female means one thing a pup and another to an adult male -same stimulus = adult female -only thing that changes is that now animal has higher level of GnRH

Teens and young adults do not receive enough sleep Why do we care?

-maybe this is normal? Why do we care? Teenagers do need a lot of sleep b/c of extensive learning happening, sleep serves as glue to consolidate info you get thoruhgout the day -when you sleep info you learn during the day gets woven into the neurons -decide what you need to hold on to and what you need to forget

Mentalizing and autism

-mentalizing is skill you need for imatation which is important when you're young Neural correlates of communicative intent in children with autism -kids in scanner and reads vignettes -sucks to get socks -things on right they heard over earphones -do kids with autisms pick up on intonations, do they pick up sarcasm? Did Ed mean what he said? 3 conditions: Neutral Instructions Attend to face Attend to prosody (voice) -1 condition they say attend to Ed's face -another condition they said attend to Ed's prosody, voice Neutral instructions: "Pay Attention" -medial prefrontal cortex -TD = typically developing -pay attention to task (neutral) -TD subjects showed more activation in medial prefrontal cortex. Children with autism did not. Most likely to say that Ed meant what he said -lack of perspective = lack of activation Difference between children with autism and controls Directed Instruction: "Attend to face or prosody" No Difference between children with autism and controls -suggests that autism people don't have broken social brain, it doesn't automatically attend to social features, when you draw attention, ppl with autism may be able to engage with social brain Less MPFC activation with greater symptom severity in children with autism -Social Responsiveness Scale Score

Does it promote adaptive risk-taking? Are adolescents more likely to take advantageous risks than adults?

-mixed gamble task -they are not told which side they prefer -asked would they accept this gamble -+$5 or -$10 -manipulate numbers on each side of pie -advantageous and disadvantagous combinations Disadvantageous risk -$18 +8 -expected value is disadventageious Neutral trial -$10 +$10 Advantegous risk +15 -5 -within the experiment, it was easy to manipulate advantagous vs. disadventagious -maybe adolescents take more risk because they are better at calculating if something bad or good will happen -adults may be so risk adverse -no overall differences between adolescents and adults, they both were good at tasks and understood them Used HLM -heirichal linear model -differences in acceptance rates based on the value on each side of the pie -you should be getting more acceptance rates in green -adolescnets and adults are both unlikely to accept disadventagious risk -overlapping in whether or not to take neutral trials -adolesents are more likely to accept adventagous risks than adults, more likely to accept risk as value of epected value increased Adolescents were better at taking advantageous risk -adolescents are discriminate in the risk taking they do, they don't treat all risks the same -as they get older, adults, more risk adverse, not going to take risk Greater ventral striatal activation in adolescents to increasing value =adults were unconcerned of he level of expected value while adolescents were tracking how much more money they would've gotten if they take the risks

Why do risky behaviors more commonly occur around friends?

-modeling? Like in rats study -taking risks around friends b/c hanging with friends more often, not the only answer -people play computer driving game, you have to go as fast as you can -yellow light - you choose whether to go or not, you crash if you don't make it -played game alone or with friend -when alone, no difference b/w teenagers, college students or adults when they run the yellow light The Presence Of A Friend Led To Riskier Decisions and Worse Outcomes -adolescents show an increase in time of running yellow light when friend is simply standing there -no change in college or adults Friends excite the reward system in adolescents -nucleus accumbens is activated in adolescents and college students -Ventral striatum = nucleus accumbens -lots of activation in adolescents in VS not to college or adults

Recent attention on the potentially harmful effects of sports-related concussions on brain development

-money drives things, NFL lawsuits that argues football causes brain damage, suicide -white house held summit on sports and concussions under obama -Steve Tisch donated 10 mil to design program to research concussions and football

Dopamine release in adolescents

-more dopamine (more vessicles with dopamine) in adolescents vs. adults -same stimulus leads to more dopamine release -more dopamine receptors to accommodate high levels of dopamine -greater release of dopamine -> greater dopamine binding -> LTP (long term potentiation) next time fires more vigirously, animal learns that ths is valuable -transitioning out of puberty into adult, you have less dopamine (reserves) less release of dopamine, you need less dopamine receptors, receptors retreat away -system doesn't know drugs are bad for you, just responding to the reward -money may have different values to adolescents

Mesolimbic circuitry is hyper-excitable in adolescents in response to rewards

-more dopamine in system in subcomponents of striatum

Primary Reward Experiment

-play computer game correctly, get a drop of juice in mouth -use fmri to see whether brain is showing activation when getting primary reward -give sugar water, salt water, water -sugar water is rewarding -salt water is punishment -water is neutral -sugar water became less pleasurable for adults, not adolescents (whole time was pelasurable) -adults decliend in how favorable they found the sugar -in response to sugar water, adolescents showed more activation than adults Reward sensitivity aligns with increase in pubertal hormones in adolescents (GnRH levels)

Puberty is a long process that is influenced by many factors

-puberty happens over many years

Is puberty occurring earlier and earlier?

-puberty is occuring earlier and earlier in both males and females (not necessarily refering to period onstart) -breast development is happening earlier and earlier in girls -1930- sample was homgoenous, white caucasian girls -2010 -sampel is more diverse -ethnic diverse girls have puberty earlier -now in 2010 they are including a more diverse group of people who may naturally have early onset of breast development -manarche seems not to have changed -age of first menstral period seems to stay the same -maybe puberty is undergoing a longer period of time than the older years

Humans activate the same reward center as non-humans

-regardless of age This brain scan shows the results of a monetary reward study conducted in children, adolescents and adults -examine each group to see if one group is more likely to show more activation There is a marked change in how organisms respond to, seek out and work for rewards across development. The greatest changes occur at two key points in development: as individuals transition in and transition out of puberty, making adolescents more sensitive and responsive to reward than other age groups.

What is special about adolescence? -Adolescent Peak in Reward Sensitivity and Hormonal Changes

-reward sensitivity: adolescents find rewards more salient, behaviorally excited by it b/c brain is having a greater neurotransmitter response to that reward -as people undergo puberty, greater release of GnRH hormones in hypothalamus Increased dopamine release in adolescents -cannot directly assess this, must use PET imaging to assess it -people get radioactivity injections, can't do it in adolescents -b/c greater activation of striatum, that means they have more dopamine -

Do we become "human face experts" because of experience?

-seems like it -but do we become experts of humans b/c we are exposed to them the most? And not something like gorilla

The Implications of Adolescent Brain Research on Policy: Sports-related Head Injury

-should we allow adolescents engage in sports that may harm them that they may suffer head injuries, football -obsession with football in this country though -some argue shouldn't limit football b/c it's such a big part of culture -argument about whethe or not football is the next tobacco Sports-related concussions account for the majority of adolescent brain injuries

Enhanced activation in the human amygdala to fearful compared to neutral faces

-showed ppl images of fearful or neutral face; brain comparison, amygdala shows a lot of actiation to fearful vs neutral faces in adults

Adolescent mice, unlike adults, consume more alcohol in the presence of peers than alone

-similar to adolescent humans -alone or with peers w/ alcohol availables -adults and adolescents Juvenile mice, but not adults, spend more time drinking alcohol in the presence of peers than alone -no difference in how much time they drink alcohol alone -when introduce mice to peers, significant increase in time spent drinking, if juvenile -modeling behavior, see one animal more likely to do it so they want to do same thing -doesn't explain why adults don't see this results -adolescent mice find alcohol less adversive -hangovers are worse when you get older -over time alcohol becomes less inviting Juvenile mice spend more time consuming alcohol when tested with their cage mates

Neural activation when viewing prosocial acts in adolescents

-simply by viewing ppl helping other ppl you 2 engage social brain and reward system

Are adolescents risk takers because of their overactive reward system?

-something rewarding about taking a risk as if you had given them money, sugar, etc -relying on computar tasks that try to apply to real world -often involves monetary risk, gambling Juvenile ("adolescent") rodents are more likely to engage in risk-taking behavior, and they seek out new situations and explore unknown areas more avidly than they do at either a younger age or in adulthood. -not only did adolescents find more pleasurable, thrill is more salient than consequences Adolescents have a higher tolerance for the unknown -more important to adolescents how rewarding is it, less likely to take into account the consequences, adults are the opposite -learn from mistakes in adolescents -fuzzy trace theory - the reason why adolescents engage in risks is not because of the overactive reward system, or thinking ahead, haven't had push back yet in terms of consequences, just base decision making = if someone offers them an opportunity to get a ride home and someone has been drinking, takes the risk because unlikely, but adult doesn't want to take that chance

Does increase in pubertal hormones during adolescence contribute to increase in neural sensitivity to reward? Specifically, what are the effects of testosterone on neural reward processing over time?

-testosterone in adults are associated with greater reward and risk taking behavior

Dopamine is released in response to a pleasurable stimulus

-we all release different amounts of dopamine to the same thing -if you like dark chocolate release lots of dopamine, if you don't then you don't release as much dopamine -can be primary or secondary reinforcers -money = secondary reward - come to learn that it has value -primary reinforcer = water, food

Is media changing/harming the developing brain?

-we don't know -not enough data, media changes so quickly too, so don't know long term repruccussions of media -is media enhancing brain development? Flip side

Adolescent brain research has been impactful in three primary ways: Helped explain adolescent behavior

-when adolescent offender is tried in court, can bring in science and show how adolescents on avg think

Brain regions that comprise the "social brain" network

-will be asked about this on the exam -aspects of social brain network crucial for emotional and face processing -amygdala: brain region not on surface of brain, other regions are cortical regions on surface of brain, work together to form network, cross region integration happens during adolescence, ability to engage with other people during adolescence increases b/c of development of regions -psTS: -Fusiform gyrus -one other

Landmark juvenile justice cases

1. Is the juvenile offender solely culpable for the crime? 2. What factors contributed to the offender's culpability? 3. Does the sentence violate the Eighth Amendment ("cruel and unusual" punishment)? a punishment is considered cruel if it is judged to be excessive given the nature and circumstances of the crime. Roper v Simmons (2005) case that abolished juvenile death penalty Graham v Florida (2010) banned the implementation of life without parole for juveniles who are convicted of crimes other than murder Miller v Alabama and Jackson v Hobbs (2012): (an extension of Graham v Florida), ruled that it is unconstitutional for states to mandate life without parole for juveniles, regardless of the crime

Adolescent brain research has been impactful in three primary ways:

1. Neurobiologically differentiated adolescents from children and adults 2. Helped explain adolescent behavior 3. Demonstrated that the brain is plastic well beyond the early postnatal years. This has helped create developmentally-appropriate expectations, policies and sanctions for adolescents

Three general characteristics, all substantiated by neuroscientific evidence, influenced these Supreme Court rulings.

1. Protracted development of prefrontal cortex (regulatory systems) limits behavioral regulation and decision making capacity 2. Juveniles are more vulnerable or susceptible to negative influences and outside pressures, including peer pressure 3. The character of a juvenile is not as well formed as that of an adult; the personality traits of juveniles are more transitory, less fixed.

Characteristics of the "reward system"

1. Rich in the neurotransmitter dopamine 2. The neural systems that process reward are conserved across age, organisms and species 3. Brain processes different types of reward in the same way -same across animals and age -what changes is the extent of activation -teenager- activation is strongest in nucleus accumbens -reward system helps you learn about the environment and what to pay attention to -cocaine region is same as food region reward, looking at loved one

Why is it important to understand adolescent brain development?

1. To understand developmental changes in behavior from childhood through adulthood 2. To understand the relation between puberty and brain function 3. To understand gains in socioemotional skills 4. Adolescence marks a period of increases in psychiatric disorders

Trends in Concussion Incidence in High School Sports

11-year study (1997-2008) Data gathered from 25 high schools in a large public school system 2651 concussion injuries boys football accounts for largest % of concussions

History of the juvenile justice system

1900-1970s: Crimes committed by juveniles attributed to their immaturity and impulsivity; Primary goal of treating juvenile offenders was rehabilitation 1980-1990s: Wave of violent crimes by "youth" led to tougher policies; primary goal was/is to punish juvenile offenders -shift from helping to punishing juvenilles because of upsoar of violence -more tough on crimes now but swinging back to the other end

Results from study designed to test youths' competence to stand trial

30% of young adolescents showed impairment on understanding, reasoning, and appreciation domains -how best do we conduct research on these questions -created psychological testoment to test understanding, reasoning and appreciation -30% of adolescents 11-13 are imparied in showing psychogolical impairment -decreases with age -why we need laws based on age or competence

What is adolescence?

A normal, adaptive, & significant period of human development characterized by substantial change, akin to early childhood in terms of opportunity to influence long-term outcomes & potential. -global perception that teenagers are terrible -teenagers can also be leaders -passionate in ideas they believe in, activists -shifts in social relationshipos -adolescence is a time of vast resilience and growth A time when individuals engage in activities & relationships that take on new meaning and nurture a sense of identity, agency, self-reliance, & social engagement. -peer relationships, romantic relationships, changing relationships of parents -experiencing first breakup, rejection, navigate being rejected by someone, building blocks of future understanding of relationships A period of life beginning with the onset of puberty & ending when individuals assume the roles, rights, & responsibilities of adulthood. Adolescence is the gradual period of transition from childhood to adulthood Biologically-initiated (puberty) and socially-terminated (with adult roles) -ending is controversial but beginning is onset of puberty -social roles are hard to define -parents, bills, financial independence, caregiving for someone else, careers, vote

When is an individual is "mature enough" to be trusted with certain responsibilities?

A period of life beginning with the onset of puberty & ending when individuals assume the roles, rights, & responsibilities of adulthood (e.g. moving away from the family, bearing children, financial independence)

When is an individual is "mature enough" to be trusted with certain responsibilities?

A period of life beginning with the onset of puberty & ending when individuals assume the roles, rights, & responsibilities of adulthood (e.g. moving away from the family, bearing children, financial independence) Varies by culture -some cultures theres a big ceramony that marks someone reaching sexual maturation or it's a big deal for someone to move out, or they don't move out of the family even when they're considered adults

What is adolescence?

A period of life beginning with the onset of puberty & ending when individuals assume the roles, rights, & responsibilities of adulthood. Adolescence is the gradual period of transition from childhood to adulthood Biologically-initiated (puberty) and socially-terminated (with adult roles)

Biological factors for shift in sleep

A. Sleep-wake phase delay (i.e. not sleepy until later) B. Transition into a more evening chronotype C. Coincide with puberty B) Chronotype refers to own preference of going to sleep -night owls, vs. morning, based on individuals, during adolescents general shift to night owl -is sleep-wake phase delay only relevant to US or humans -this happens across cultures and across species

The Implications of Adolescent Brain Research on Policy: Teenage Driving

Accidents are leading cause of teenage death -how do we prevent teenagers from killing self in accidents Car accidents are leading cause of teenage death Adolescent fatalities are even higher among: 1. adolescent males 2. driving with teen passengers 3. new drivers

Sleep is a basic human need

Adolescence is a critical developmental window when sleep exerts effects on physical, brain and cognitive development (Carskadon, 2011; Dahl & Lewin, 2002)

Conclusions

Adolescent brain research has made significant contributions to the lives of adolescents through policy and legal means However, there is still more work to be done to ensure that policy and legal sanctions for youth are based on research

Neurobiologically differentiated adolescents from children and adults

Adolescents are not simply "mini-adults" nor are they overgrown children Although they have better reasoning skills and overall cognitive ability than children, they still lack mature emotion regulation and life experience -adults are less influenced by peers, emotional circumstance -looking at intellectual ability, around high school age 14-16, intellectual ability is similar to adults,calculus, -adolescents still lag in terms of psychosocial maturity, only about 25% of high school studnets have psychosocial maturity that adults do, doesn't start increasing until college age -disconnect in high school in intellectual ability and psychosocial maturity -why adolescents aren't mini adults (low psychosocial maturity) but not overgrown children (adult like intellectual ability) Adolescents are not simply "mini-adults" nor are they overgrown children: Why is this an important distinction? Historically, lawmakers have tended to binarize age boundaries, which has implications for legal sanctions ''minors,'': who are presumed to be vulnerable, dependent, and incompetent to make decisions, Adults: who are viewed as autonomous, responsible, and entitled to exercise legal rights and privileges -how you categorize someone in terms of emotional competantance is how legal system categorizes people -minors are 17 or younger -adult if 18 or older -rather arbitrary 17 vs 18

Summary

Adolescents exhibit heightened activation in mesolimbic circuitry relative to adults This phenotype may have advantages in terms of learning, risk-taking and well-being -people who had more activation in reward game, even if they felt stressed about election were less likely to report depressive symptoms

Greater amygdala activity for learning emotion-object associations vs emotion alone

Amygdala is more active to CUES that predict the emotion rather than the emotion itself -show picture and sound of woman screaming: amygdala cares about that -if you show picture of cue that predicts women screaming (orange square) if you learn to associate orange square with screaming person, that orange square can activate amygdala -amygdala is also learning center that helps you learn about emotions in envrionment

In adults, the reward center (ventral striatum) is also implicated in reinforcement learning

Animal work shows that dopamine is a learning signal

Dual Systems Model

At puberty, increases in dopamine within the socioemotional system leads to increases in sensation seeking and risky decision making, outpacing the development (and engagement of) the cognitive control system. This temporal gap leads to heightened vulnerability to these behaviors during adolescence -increase in dopamine at adolescents that causes them to seek out more thrill -limbic regions (hot) systems weigh down behavior, bias behavior more than cool systems (prefrontal cortex) -2 systems in brain hot vs. cold (control system) -hot system: makes you emotional -cool system: cools you down helps you control behavior -gap in development b/w these regions lead to more likelihood of thrill-seeking behavior

Conclusions: ASD

Autism spectrum disorders are characterized by deficits in social understanding, eye gaze, mentalizing and face processing Neural regions in the social brain that support these social cognitive skills display atypical activation in children with ASD Atypical activation of social brain regions may be the result of lack of typical social processing

Culturally-independent sleep changes

Bedtime gets later from early to late adolescence in the U.S. Rise times stay the same Observed in over 20 countries on six continents, in cultures ranging from pre-industrial to modern (Hagenauer & Lee, 2012) retrospective longitudinal measures indicate that teenagers exhibited later sleep times than children or adults before the advent of modern technology -people undergo phase shift during adolescents Bedtime gets later from early to late adolescence in the U.S. Rise times stay the same Bedtime gets later from early to late adolescence in Korea Rise times stay the same -korean studnets go to bed even later than americans starting from 6th grade -shows the same trends and also show early rise time -exact # of hours differ b/w cultures but patterns are similar -early school start times: area of debate b/c if we want adolescents to sleep more can't change when they go to bed, change when they wake up

Roper v. Simmons (2005)

Capital punishment is found unconstitutional for individuals under the age of 18 years -christopher simmons murdered 46 yr old woman -lawyers aruged developmental delay -capital punishment = execution "(1) "As any parent knows and as the scientific and sociological studies... tend to confirm the lack of maturity and an underdeveloped sense of responsibility were found in youth more often than adults and were more understandable among the young; "(2) juveniles were more vulnerable or susceptible to negative influences and outside pressures, including peer pressure; and "(3) the character of a juvenile was not as well formed as that of an adult. The personality traits of juveniles are more transitory, less fixed" the U.S. Supreme Court created a new standard for the death penalty--it is now a violation of the Eighth Amendment to execute anyone who committed murder prior to the age of 18. -in some states you can try someone as an adult even if they are younger than 18

Donation Opportunity

Charity for foster youth Donate any portion of their study compensation to charity ($0-14) Experimenter left the room while participants completed this phase of the study -manipulation: either viewed prosocial acts before or after opportunity to donate money -prosocial scene -social scene -or non-social scene -latter 2 are controls -found when people had opportunity to give money after social scene gave more money than when social scene was after donation task -priming effect of showing prosocial scenes Research participants donated more money if they had viewed the prosocial images before donating money than if they had viewed them after donating money -how to we categorize prosocial situations vs. social situations? -what codes monitors prosocial behavior? TPJ TPJ=Temporoparietal junction: implicated in perspective-taking

mini summery

Children shift their face processing strategy from a features-based one to a whole-face approach (configural processing) as they become adolescents This is supported by development of the social brain network -eye tracking exp: children more looking at individual components of faces (eyes, mouth, nose) adults use whle-face approach looking it as a whole unit, why adults are better at processing emotiaonly information -individuals diagnosed with autism show a similar piecemeal evaluation of face only focusing on mouth as opposed to taking entire face as whole, implications of how they can understand what people are thinking

The Implications of Adolescent Brain Research on Policy: Juvenile Justice

Competent participation of the individual in his/her defense is written into our Constitution Criminal defendant's ability to stand trial, measured by their ability to understand the proceedings and assist their attorneys Adolescent research helps policy systems define "competence" -adolescents getting tried in adult court are more likely to come back into system, commit another crime -motivates keeping adolescents from court system -why do they commit more crimes with adults? -influenced by peers, even more influenced by ppl slightly older than them -challenging to understand legal way of speaking -

Children's amygdala is most responsive to neutral

Consistent with notion that amygdala detects threat; context-specific -neutral compared to other emotions, more activated to neutral than other emotions in amygdala -kids are most threatened by neutral face -not adaptive for us to be concerned of neutral face when we're older b/c we're exposed to more neutral faces when we're older Amygdala response to neutral faces decreases with age Amygdala response to fear faces increases with age -consistent with threat detection center theory; threat can come from scared faces Summary Main neural regions critical for social cognition: superior temporal sulcus, amygdala, orbitofrontal cortex Face recognition becomes more 'human-specific' with age Emotion processing improves with age

The FFA shows greater activation from childhood to adulthood, which coincides with people becoming better face processors

Consistent with refinement of the fusiform face area based on experience with faces -increased activation in brain region as people become better at identfying faces and facial expression, not born with a lot of activation in FFA, over time brain engages region more b/c it's our expertise region

Face/social recognition deficits

Continue to focus on features of the face rather than configural processing (processing the whole face at once) Lack of activation of the fusiform gyrus when viewing faces in individuals with autism (e.g. Humphreys et al 2008; Scherf et al 2010) -trouble recognizing expressions in face -continue to foucs on features of face rather than taking face as one -autism kids focus on mouth because it moves (more salient) -lack of activation of FFA important for processing faces, -is it the case that they don't activate FFA b/c less experience of looking at faces or is it the case that FFA was never orienting them to faces which is why they don't have interest in them During an emotion processing task, less activation in fusiform gyrus and amygdala in the group with autism (right side of panel) -brain is not picking up on emotions as quickly or automatically as indiviuals w/o autism -

Face vs Object processing

Differences in interpretation: 1) evidence for neural specialization of face processing 2) faces simply another category of objects -brain doesn't treat faces as any other objects (1) -faces is simply another category of objects (2) -b/c we see faces so often, we're giving brain overrepresentation of face processing, presentation

The original goal of the juvenile justice system

Divert young offenders from the destructive punishments of criminal courts Encourage rehabilitation based on the individual juvenile's needs Maintain public safety

Is heightened sensitivity in the mesolimbic system beneficial?

Does heightened mesolimbic sensitivity enhance learning? Does it promote adaptive risk-taking? Does it promote psychological well-being?

Puberty and brain function

Emotion processing Face processing Reward processing

When is an individual is "mature enough" to be trusted with certain responsibilities?

Employment- AGE 14 Driver's license - 16 Vote; serve in army- 18 buy alcohol - 21 rent a car - 25 -voting and armed forces are intertwined, lowered age to serve in army from 21 to 18 so voting had to be 18 too People are marrying later =in 60s: median age was 20 for women, and 22 for men -in 2015: median age is 27 for women, and 30 for men Financial independence takes longer to achieve -cost of college is much more than it used to be, so it's harder for college students to suppor tthemselves in college -public school changed from $7,000 -> $15,000 -privtae school is now $40,000 vs. $15,000 -isn't as easy to equate maturity with marriage or financial independence Financial independence takes longer to achieve Economic crises 39% of adults, ages 18-34, live with their parents (U.S. census data, 2011) 53% of 18-24 year olds report living with parents either temporarily or permanently 60% reported being financially supported by parents

Is media changing/harming the developing brain?

Extensive research on media and the brain but we do not yet have firm answers

Direct investigation of dopamine in the human adolescent brain is not possible

Eye blink rate (EBR)=indirect measure of dopamine -eye blink rate- thought to be associated with arousal -dopamine does more than just reward, it enhances our arousal -first observed in monkeys, Relationship between eye blink rate and PET imaging In monkeys, EBR is positively related to D2 receptor availability and sensitivity to rewarding feedback -activation in striatum is reflective of levels of dopamine in monkey brain -x-axis = basilcally dopamine levles -y-axis is EBR -in 3 regions they measured, there is a strong relationship between dopamine and EBR -higher dopamine = higher EBR

Individuals with autism show deficits in:

Face processing Eye gaze Face/social recognition Mentalizing -difficulty with communicating b/c you lack face processing skills -eye gaze: autism individuals don't look at eyes Individuals with autism fail to follow the stereotypical pattern of "tracing" a face compared to individuals without autism Possible explanations: Lack inherent interest in the social components of the face (i.e. eyes) Viewing faces is too arousing, so much so that it is aversive (i.e. sensory overload) -we typically look at eyes mouth then eyes -individuals with autism: eyes are not central focus of gaze, no typical pattern -lack of attention to eyes = lack of info that comes from eyes -leads to awkard social dynamics

To what is FFA responding?

Faces OR Individual level - Expertise To test this, a group of investigators trained people to become "experts" in novel stimuli -from the moment you're born, you see so many faces so you have to become a face expert -maybe FFA is just an area of expertise

Does greater excitability of dopamine-rich regions in adolescents confer learning advantages?

Feedback Learning Task -learning from trial and error in the beginning -over time you'll learn which flower is correct -see butterfly and 2 flowers, guess which flower butterfly prefers -80% of the time prefers one side to the other -random bird house, every trial had a random picture associated with it Adolescents exhibit better feedback-based learning than adults -they found in the beginning both groups preformed above chance -over time adolescents had better learning than adults -challenges assumption that adults are better than adolesents at learning Brain activation in the nucleus accumbens was greater in adolescents -both get same information, that you did something correctly, but adolescents is more excited than adults by that information -adolescents less effected by negative feedback relative to adults or positive feedback -hippocampus more engaged in adolescents than adults when receiving positive feedback Brain activation in the nucleus accumbens and hippocampus greater in adolescents -adolescent brain is more receptive of positive feedback In adolescents only: strong communication between the brain's learning regions (mesolimbic regions and hippocampus

Deficits in the mirror neuron system (MNS) in children with autism

First discovered in the motor cortex of the macaque, mirror neurons fire both while a monkey performs goal-directed actions and while it observes the same actions performed by others. This observation-execution matching system is thought to provide a neural mechanism by which others' actions and intentions can be automatically understood -neurons in brain in IFG inferior frontal gyrus, that are active whn either you perform an action or see someone else perform an action -helps you imitate other people

Factors that influence pubertal timing

Genetic factors Weight Ethnic differences On average, ethnic minority girls undergo puberty earlier Stress More stressful environments linked to earlier puberty Family composition Father absence linked to earlier puberty -girls experience puberty around the same age as mom, or aunts -weight: earlier puberty, you need to have relatively higher BMI, body fat, contriutes to pubertal timing -athletes have puberty later because they are leaner -stress -releases cortisol, also released in hypothalamus, maybe release of cortisol activates hypothalamus to release GnRH, hasn't been proven, psychological idea: if you grow up in stressful environment and if goal is to reproduce for survival, you don'tk now how long you will live, evolutions perspective important to strat reproducing as soon as possible -family composition -grisl raised by stepfather also have earlier puberty -living in home w/o father is stressful

Pubertal hormones are released in the brain

Gonadotropin releasing hormone (GnRH) is released from the GnRH neurons in the hypothalamus There are only 1000-3000 GnRH neurons in mammals -very low levels of GnRH exists in the brain before puberty, after puberty GnRH releasing hormones don't release anything are dormant -only job is to trigger puberty -low number of GnRH neurons in mammals -why? GnRH neurons live only in hypothalamus, brain is conservative so not going to spend energy on neurons you don't need, only use GnRH neurons during a particular time so don't eed som any

Graduated Driver Licensing (GDL) laws

Has effectively reduced teen drivers' fatal crashes by 38% 1. Need fully licensed adult in car, no driving alone or with peers (delayed development of pFC, need someone more skiled to advise you) Limited behavioral regulation (because of delayed PFC development) 2. Daytime driving only, no nighttime driving that is unsupervised, no peers Teens are susceptible to peer influence 3. 18 years old, then you can get a full regular licesnse Teen brain matures over time=better decision making

Other measures of physical growth

Height Girls: 3.5 inches/year; Boys ~4 inches/year Weight Bone age The closing of the gap between bones, at the epiphysis, is often used as a marker that signifies the end of puberty -fusion of bones makes it look older

Summary

Heightened mesolimbic sensitivity in adolescents is not unique to reward sensitivity And confers advantageous learning and memory relative to adults Adolescence may be an optimal period for feedback learning

Melatonin release changes

Hormone that causes drowsiness and lowers body temperature Levels rise in the evening Marker of circadian timing system Melatonin release is delayed in teenagers Suppressed by natural and artificial light -helps you start to sleep when sun goes down, -natural light suppresses melatonin -adults start to release melatonin around 6/7 o' clock, teenagers start later Suprachiasmatic nucleus influenced by light and pubertal hormones -find above hypothalamus, reacts to melatonin -primary job is to regulate circadium rhyhtm (24 hour cycle) -our internal body keeps circadium time as it relates to the sun -doesn't know the difference b/w natural light and artificial light (screen, phone) -tricks suprachiasmatic nucleus into thinking it should be awake Blue light tells our brain that it isn't time to sleep -if it's light outside, we should be wide awake and alert Blue wavelength light is short, red wavelength is long -disruptions to circadium rhythm through melatonin suppression Mechanism of melatonin suppression -during day when light is outside, light inhibits melatonin from being released -lack of light stimulates release of melatonin -the normative delay of when adolescents release melatonin interacts with screen time before they go to bed, make it worse by looking at screen, further supressing release of melatonin ~75% of teens use a computer or cell phone before bed 96% use some form of technology -tv remains #1 way teenagers, tweens are interacting with technology

Endocrine system

Interactions between the pituitary, thyroid, and adrenal glands lead to adrenarche and gonadarche =these 3 glands are in constant communication during puberty b/c they are important -pituitary thyroid and adrenal gland together stimulate additional pubertal changes Adrenarche is an early sexual maturation stage of puberty (typically ~6 to 8 yrs) Oiliness in skin, body odor, pubic hair Gonadarche (typically ~8-10 years) First menstrual period, ejaculation -adrenarche- early in sexual maturation, -puberty is a long process there is no one single age at which everyone undergoes puberty Between ~9 - 16 years in most adolescents -puberty is occuring earlier and earlier in both males and females (not necessarily refering to period onstart)

What "re-awakens" GnRH for the activational role?

Internal and external cues trigger GnRH -can mean a lot of different things -funnel at top represents integration of info from internal and external cues (body weight, level of stress at home) -integrator is unkown Innate clock that times the unfolding of primary genetic programs -clock at top refers to hypothesis that perhaps not something starts puberty, is that each person is on some developmental clock that starts ticking when they're born and body just unfolds in such a way -less to do with what's going on around you just some timeline you are on -infers that menopause is also on some sort of clock -girls undergoing puberty earlier have menopause later, not a coincedence in pattern of timing across lifespan

Peters and Crone Paper

Investigated whether adolescents show enhanced striatal activity during feedback learning, and whether this enhanced activity is associated with better learning performance over time. N=736 scans, age 8-25, scanned multiple times -over time part is important -had 700 scans scanned mupltiple times In the beginning, it is a trial-and-error task; as people learn which box is correct (based on feedback), they learn the correct answer -tell us which box animal goes into -+ sign if correct, - if incorrect Less brain activation to positive feedback in older versus younger people -as people get older, less activation in nucleus accumbens (figure on the right) -not b/c people are performing worse when they're older, less reaction in nucleus accumbens Explored whether activation in mesolimbic regions could be used to predict future learning performance years later Activation at time 1 (TPI1) predicts learning at time 2 (TP2); activation at TP2 predicts learning at TP3 -activation in caudate allowed researchers to understand how well you'd preform 2 years later at time 2, time 2 was indicative of how well you learn at time 3 -reminiscence bump: memories from adolescence if incredibly salient -why music preference has such a tie to the music we listened to when we're young (women: 13, men: 14)

Puberty is so cool!

It is not random It follows a prescribed sequence of events (same neural regions, same hormones) in every individual Always initiated in adolescence (not in toddlers, college students, older adults) This means that over evolutionary time all species have determined the optimal developmental time for sexual maturation in all members of the species -everyone undergoes puberty - not random -girls - breast development, hair dev, menstrual period -boys - -if puberty happens around 10 or 11 years old, maybe that's how long we need to be taken care of -in humans long delay in when you reach sexual maturation vs. when you actually start reproducing -maturity gap: biologically sexually mature (adult) but not treated as an adult -10-15 years b/w sexual maturation and being considered an adult - -extensive variability in puberty (14 year old) look very different -implication in psychological development, some boys have growth spurt earlier than others, gives us a sense of how mature someone is physically, socially, emotionally, based on how people look b/c puberty is a long process

Homeostatic regulation changes at puberty

It takes much longer (16 hours) for a 15-year-old to feel as much sleep pressure as a 2 year-old does after 4 hours -sleep pressure related to homeostasis, regulates need for sleep = sleep pressure -how much pressure does body giv eyou to go to sleep -similarly to how hungry you are -sleep pressure related to homeostasis, regulates need for sleep = sleep pressure -how much pressure does body giv eyou to go to sleep -similarly to how hungry you are -adolescents show sleep pressure that can sustain longer hours of wakeness -adolescents can go 16 hrs without feeling too much sleep pressure while younger kids feel sleep pressure earlier, 4 hours feel sleep pressure for 2 year olds

GnRH triggers the secretion of the hormones LH/FSH

LH=Luteinizing hormone FSH=follicle stimulating hormone 1. GnRH gets released increase in mature animal 2. Leads to release of high levels of LH/FSH 3. Leads to testosterone and estrogen production LH controls testosterone production in males and estrogen secretion in females -everyone has circulating levels of testosterone, and females have circulating levels of estrogen -varies across life span based on life events -testosterone decreases after man gets married and decreases after having children -testosterone leads to sexual behavior and agression FSH stimulates sperm production inmales and follicle development in females -body hair, body odor changes, physical changes -happens throughout life, tapers out at some point -not the case that GnRH is needed forever in order to have testosterone secretion etc., it just jumpstarts the process of this person is sexually mature

Potential explanations for higher driving accidents among adolescents

Lack of ability to attend to driving tasks (immaturity) This explanation argues for delaying full licensure for adolescents until they have become "mature" Driving inexperience This explanation argues for more policies that consider brain maturation and experience as important influences on driving ability -adolescents are immature, can't attend to many different tasks -driving inexperience: need to practice skills -delaying licesnure doesn't work, decreased fatality of 16 yr old, but increased fatality at 18 the new age of licesnure

fMRI study of neural activity during the imitation and observation of facial emotional expressions

Less activation in ASD children (right) than typically-developing children (left) in the mirror neuron system during imitation -some activation of mirror neuron system with autism group but significantly less than typically-developing group The worse their symptoms of social deficits, the less activation of the mirror neuron system -don't know if behavior is affecting brain or brain affecting behavior but there is an association Conclusions of Wang Study Children with autism show the same neurobiological profile as TD kids if their attention is directed to social aspects of the task May be a useful intervention strategy -training ppl to pay more attention to faces, imitate more, reawaken regions in social brain

Graham v. Florida (2010)

Life without parole is found unconstitutional for individuals under the age of 18 years convicted of crimes other than homicide 16 yr old wanted to rob restaurant. Armed robbery with assault and battery, tried as adult for some reason, 6 months later arrested again for armed robbery, charged with life in prison w/o parol, punishment too much for crime committed -life w/o parole means you're in prison forever -parole: appeals after certain time has passed that you've changed in character "Developments in psychology and brain science continue to show fundamental differences between juvenile and adult minds. For example, parts of the brain involved in behaviour control continue to mature through late adolescence." The Court decided that punishments for crimes should be "graduated and proportional," ruled that a sentence of life in prison without parole for juveniles convicted of non-homicide crimes was, in fact, in violation of the Eighth Amendment. However, they upheld the sentence of life in prison without parole for juveniles involved in homicide crimes as constitutional.

Reasons for the resistance to earlier school start time

Logistical considerations Reduced time for athletics and sports games Reduced opportunity for after-school jobs Childcare for younger siblings Transportation issues Challenges for in family schedules

Deficits in the mirror neuron system in children with autism

MNS activity in the human homolog of the macaque motor cortex—the pars opercularis in the inferior frontal gyrus (IFG)—has been consistently reported during imitation, action observation and intention understanding

Delayed pubertal onset

Malnourished Anorexic High physical activity

How much autonomy should adolescents have about health decisions?

Mature Minor Doctrine Policy accepting that adolescents may have the maturity to make heath care treatment decisions by themselves E.g. reproductive health -immaturity in thinking about future in adolescents -it is important for them to have autonomy though -policy that recognizes that adolescents should have privilege to make own health care decisions especially in reproductive health -reasons why adolescents shouldn't be held accountable for crimes because heat of moment, imput from limbic system, for decisions to be deliberative about, pFC has a more mature position, able to think through and reason through these types of decisions

Is there a perceptual narrowing for faces (as there is for language)?

Methods 11 adults 30 9-month old infants 30 6-month old infants Discrimination: the ability to distinguish between two objects (faces) -need all face processing resources to go to members of own species Hypothesis: if face recognition follows the same developmental pattern as language, the ability to process other species' faces will be present only in the youngest age -only observed in 6 month old kids

"window" for face processing remains open if not exposed to faces early in life

Monkeys were not exposed to faces for 6, 12 or 24 months Were then exposed to either monkey or human faces for 1 month -experience expectant mechanism -if individual doesn't see faces for 2 years of life, face processing mechanisms remain open, able to identify faces of other species until they get exposed more to members of own species -researcher wears bag of had so don't see faces -monkeys became very godo at discriminating faces of whatever species they were exposed to

-how does body know when to stop producing hormones?

Negative feedback loop controls the amount of hormone -turns off the beginning of loop and slowly less and less release of GnRH

Face processing in newborns

Newborns can imitate facial expressions Newborns show preferential orienting towards faces (Johnson et al 1991) Newborns look longer at the mother's face than a stranger's face (Pascalis et al 1995) =maybe mother's smell is specific to mother, but look at image and know it is their mom Children shift their face processing strategy from a features-based one to a whole-face approach (configural processing) as they become adolescents This is supported by development of the social brain network

Early pubertal onset

Obese individuals Individuals who are reared in stressful environments Poor family relationships

Autism: A Lifelong Developmental Disorder

Onset occurs before 36 months of age Prevalence: ~1 in 68 American children are on the autism spectrum—an increase that is 10 times greater than 40 years ago. Worldwide: 1/160 children have an ASD 4-5x more common in boys than girls (1/42 boys and 1/189 girls in the U.S.) -different trajectories for different dev. Disorders -ADHD can be aged out of -not true with autism -lifelong dev. Disorder -worldwide may be less access to care, less diagnoses -US change probably has to do with awareness and diagnosis of it, some people argue environmental factors but no good evidence -vaccines don't cause autism DSM-V Criteria 1. Persistent deficit in social communication -- abnormal back-and-forth communication --failure to initiate or respond to social interactions 2. Communicative dysfunction domain Delay or absence of spoken language Difficulty in initiating or sustaining conversations Repetitive language Imitation deficits Eye gaze aversion 3. Repetitive patterns of behavior Preoccupation that is abnormally intense Inflexibility (insistence on sameness/routines) Repetitive body movements Preoccupation with sensory qualities of objects -not everyone with autism have all of these deficits, there is a spectrum -aspergers has some social deficits as autism without language deficits To Meet Criteria Must demonstrate at least 6 of the 12 symptoms At least 2 symptoms must come from the social domain and 1 each from the other domains Symptom presentation before age 3 Asperger's Syndrome Same social deficits and behavioral profiles but no language delays

Does mesolimbic activation promote psychological well-being?

Optimal well-being can be achieved through eudaimonic activities (e.g. meaning and purpose). -Prosocial behavior: eudaimonic bheavior Hedonia Pleasure Desire Self-interest Extrinsically rewarding Eudaimonia Meaning Purpose Prosocial behavior Intrinsically rewarding Expressing gratitude

Poor sleep impacts:

Physical Health and Safety Increased obesity Lower levels of physical activity Higher rates of car accidents Mental health and behavior Increased risk for anxiety, depression Emotional dysregulation Decreased positive affect Academic performance Disruption in learning and cognitive processes -sleep is related to symptoms of anxiety and depression -target this in adolescents before using CBT meds -virtious to perform on least amount of sleep per night but sleep is imporant -refocus efforts on improving sleep to improve performance

Plasticity=possibility

Plasticity: brain reshapes and refines itself in response to the environment to fit the needs of the individual. This renders adolescents more vulnerable to negative influence (e.g. substance use, peer influence) However, it also makes adolescence an ideal time to positively influence or redirect problem behaviors -plasticity means you can still change someone's behavior -can still change life outcome of someone Policymakers use this knowledge from developmental neuroscience research to determine the best interventions/sanctions/expectations of youth

Which piece people add to is an indication of their bias

Probability Maximizing (Pmax): increases the overall probability of winning money compared to losing money. Loss Minimizing (Lmin): reduces the magnitude of largest monetary loss (-$4 to -$8.50) Gain Maximizing (Gmax): increases the magnitude of largest monetary gain (+$3.50 to +$8.00). Measure of reward sensitivity Increasing blink rate predicted increasing reward sensitivity for adolescents only -no relationship in selection and reward sensitive choice and eyeblink in adults -in adolescents, higher EBR means they have a tendency to reward sensitive choice -adolescents overall try to maximize the reward, and it is important to consider how much EBR is in relationship to sensitivtiy -adolescents w/ more dopamine mean they will be most likely to seek out reward

Amygdala

Processes emotion Lesions to the amygdala impair recognition of facial expressions of emotion, even when they leave other aspects of face processing intact (Adolphs et al 1994).

Amygdala

Processes emotion and social behavior Lesions to the amygdala impair recognition of facial expressions of emotion, even when they leave other aspects of face processing intact (Adolphs et al 1994). -socially acceptable behavior: don't stand close to people because that's odd, you learn what's typical in environment, monkey has similar social rules, lesioning monkey amygdala,

Posterior superior temporal sulcus

Processes eye gaze Responds to moving eyes and mouth Monitors intentions -monitors biologically relevant stimuli, movements conspecifics do (conspecifcs = same species) -processes eye gaze and intention on it (lieing = shifty eyes) -moving eyes and mouth (social information to talk to you, display forms of emotions) -monitors intentions based on physical, biologcail information

Posterior superior temporal sulcus

Processes eye gaze Responds to moving eyes and mouth Monitors intentions Lack of eye gaze may lead to lack of pSTS engagement; may subsequently impact development of the pSTS -autism vs. contorl -lack of eyegaze may be because lack of activation in pSTS -if you don't look at eyes, the area that cares about it will stop paying attention, less reason to -studying faces early on is important to build the social brain network Lack of pSTS activation in youth with autism (right) as compared to youth without autism (left)

Why adolescents sleep less

Psychosocial Reasons Media/technology Schoolwork Extracurricular Activities Sleep Environment Incorrect assumptions about sleep need Bioregulatory Reasons Puberty / sex hormones Changes in melatonin Sleep Shift Delay Neurobiological changes -both biological and psychosocial reasons why adolescents sleep less -in other animals as well, changes in sleep -sleep shift delay: need to sleep is delayed for about 2 hrs, preference for later bet and wake times -trying to catch up on sleep: social jet lag, has effect on body as if traveling to different time-zone -shift body back and forth that is too severe, doesn't have same effect as getting enough sleep during week

Implications of Graham v. Florida

Retroactively reversed ruling of another 17 year old who had been sentenced to life without parole

Patient S.M.

She is a 44-year old mother-of-three, who suffers from a rare genetic condition called Urbach-Wiethe disease, which has caused parts of her brain to harden and waste away. Completely destroyed amygdala -we have 2 amygdali, both not functional in this woman -nothing scares her, odd social behavior She has normal IQ She has no motor or sensory impairment, and no notable deficits in intelligence, memory, or language function. However, she has trouble recognizing the emotion of fear . -she needs a 24 hr caregiver, b/c fear is very useful for us, might get yourself in trouble When asked to rate the intensity of emotion in a series of photographs of facial expressions, she cannot recognize the emotion of fear Each colored line represents the intensity of the emotions judged in facial expressions. S.M. recognized happiness, surprise, anger, disgust, sadness and neutral qualities in facial expressions compared to controls. However, she failed to recognize the appropriate amount of fear (orange lines). -she can recognize other emotions but not fear, barely registers it as something that is intense, doesn't register as something that ellicits emotions in her -brain-damaged controls: The investigators next asked S.M. (and the brain-damaged control subjects) to draw facial expressions of the same set of emotions from memory. S.M produced skillful pictures of each emotion, except for fear -took her a long time to draw fear, different from other facial expressions which she does head on -this is what I iagine people fear, she doesn't herself feel fear, -she's never felt fear No fear to fearful stimuli -snakes, tarantulas or haunted houses -interest and giggling but not fear Odd social behavior Stands too close to other people

Changes in emotion processing with age

Showed participants masked images of faces and houses (500 msec) Asked them to identify object as face or house 18 children (5-11 years old) 19 adolescents (12-17 years old) 21 adults (18-35 years old) -do children have a differnet neural representation of fear than adults? -as you get older you have more opportunities to have emotions -masked image -submiminal image -identify face or house not angry or sad -can't make out details Children's errors specific to neutral faces -faces were not all same faces -some faces had anger, fear, happy, neutral, calm -overall adults and adolescents were good at task good at discriminating b/w face and house -kids were pretty good when face were anger (90% accuracy) but when neutral face (pretty bad at saying that that was a face) -angry facial features are more salient -neutral faces interesting for kids, neutral is facial expression that most kids don't have experiences with, adults do though, kids have animated interactions with people

summary

Sleep delay in adolescence is a product of psychosocial and biologically-mediated factors Pubertal hormones influence changes in circadian rhythm and sensitivity to light School start times may be one way to enhance sleep in adolescents Adolescent neuroscience research has an increasingly important role in health decisions and concussions

Fusiform gyrus is the most important brain region for face processing

Specialized for face perception Sometimes referred to as the "fusiform face area" Fusiform face area (FFA) exhibits the greatest activation to faces compared to objects, houses, other body parts -looking at actual brain signal, activation to faces -every time you see face increase activation, every time you see object no response

Jackson v. Hobbs (2012) and Miller v. Alabama (2012)

States may not mandate life without parole for individuals under the age of 18 years, even in cases of homicide -14 yrs old whenc ommiting crime -beat and robbed neighbor, set fire to neighbors trailer, died of smoke inhalation -jackson attempted to rob store with 2 18+ kids, confessed Justice Kagan: "that mandatory life without parole for those under age of 18 at the time of their crime violates the 8th Amendment's prohibition on cruel and unusual punishments." "Mandatory life without parole for a juvenile precludes consideration of his chronological age and its hallmark features — among them, immaturity, impetuosity, and failure to appreciate risks and consequences It prevents taking into account the family and home environment that surrounds him — and from which he cannot usually extricate himself — no matter how brutal or dysfunctional" "The evidence presented to us ... indicates that the science and social science supporting Roper's and Graham's conclusions have become even stronger... It is increasingly clear that adolescent brains are not yet fully mature in regions and systems related to higher-order executive functions such as impulse control, planning ahead, and risk avoidance." Juveniles show ''heightened capacity for change" "I conclude that the neuroscientific evidence was probably persuasive to the Court not because it revealed something new about the nature of adolescence but precisely because it aligned with common sense and behavioural science."

Neutral faces have different meanings for children vs adults

Stranger connotation Punishment Ambiguous -strangers give neutral faces to kids -kind of angry or annoyance is a neutral face -neutral is ambiguous, don't know what they are thinking -hard to know what someone is tinking with neutral

Visual paired comparison task

Subjects presented with two images (one familiar and one new image) Recognition is inferred from the participant's tendency to look longer at the novel stimulus (this means that they recognize the familiar image) -look longer at novel stimulus b/c that's new information -examined how long they looked at each face -look longer at novel face in all 3 age groups The ability to discriminate faces of our own species develops very early in life Do humans have the ability to discriminate faces of other species? -differences in how age groups treated novel vs familier monkeys -adults are bad at distinguishing the monkeys -9 month olds were bad too -6 month old babies were good at distinguishing between monkeys Only those who have not yet undergone perceptual narrowing

In humans eye blink rate is

Suppressed in individuals with Parkinson's Disease (Karson et al 1982) Correlated with impulsivity (Colzato et al 2009) Increased in children and adolescents following treatment with a dopamine agonist (Sallee et al 2003) -Parkinson's disease: lack of dopamine = cannot have smooth muscle movements -children receiving dopamine agonist show higher EBR Participants 25 Adolescents 26 Young Adults -variaiblity of EBR Roulette Game -make choices even they don't know the outcome of their choices -red = +$8 -green = +$0 -blue = -$6.50 -reward seeking behavior: adding 2 dollars to +8 condition, gain maximizing, still 1/3 chance of getting nothing and losing money (RED) -adding it to 0 you'll now have 2 dollars -adding to blue: you're losing less, minimizing loss, lose only -6.50 now, more concerned about losing, -adding to green: probability maximizing person, if you add 2 to green, you have 2/3 chance of winning something

Activation to prosocial versus social scenes

TPJ=Temporoparietal junction: implicated in perspective-taking the extent to which the TPJ was recruited in prosocial contexts was associated with an individual's propensity to behave prosocially -more activation = more donation The TPJ has also been linked to greater perspective taking in adolescents, suggesting the evaluation of prosocial scenes in the present study may have required perspective-taking skills relevant for engaging in prosocial behavior. the extent to which the TPJ is recruited in prosocial contexts is associated with an individual's propensity to behave prosocially. -activation in laboratory is predictive of actual behavior outside of MRI

The Implications of Adolescent Brain Research on Policy: Juvenile Justice

The U.S. Supreme Court's ruling on criminal behavior in juveniles is the most impactful consequence of this research The role of the juvenile justice system is to: 1. Determine the culpability of the juvenile offender 2. Assess the juvenile's capacity for change Neuroscience data have been used to support the position that adolescents are less mature than adults in ways that diminish their criminal culpability 1. Determine whether or not someone committed crime they are accused of 2. Determine capacity to change -some believe that we shouldn't treat adolescents categorically, case by case basis -regardless of crime, brains are not as mature as adults

summary

The heightened adolescent sensitivity to reward may lead to adaptive risk choice Suggests a more flexible reward system--one that encourages more or less risky behavior based on options.

Why is the mesolimbic reward system referred to a "motivational" system?

The mesolimbic reward system is commonly referred to as the motivational system in the brain because it plays a large role in motivating and mobilizing organisms. -mesolimbic -> dopamine -reward reinforces behavior, identifiying food sources -reward motivates you even if reward isn't immediate -pFC helps us think about the future Complex network of brain regions makes up the "reward system" Nucleus accumbens - striatum looks like heart, bottom of heart is where nucleus accumbens is -Looking at dopamine release in nucleus accumbens

Conclusions from Pascalis et al

The perceptual mechanisms that underlie face processing are initially broadly tuned and becomes more specialized for specific types of discriminations with experience. "Our experiments support the hypothesis that the perceptual window narrows with age and that during the first year of life the face processing system is tuned to a human template."

Theoretical models of adolescent brain development

These models tend to highlight the differences in maturation rates of brain systems implicated in emotion, social an reward processing from those that are important for regulation of behavior

Triadic Model

This model attributes the determinants of motivated behavior to three functional neural systems, the prefrontal cortex, the striatum and the amygdala, and focuses on how the maturational timing of each region contributes to age-related differences in motivated behavior (Ernst)

Imbalance Model

This model posits that developmental changes in the neurochemical, structural, and functional composition of the brain proceed on distinct timelines, such that some brain regions exhibit the changes earlier in development than other brain regions. (Casey) This leads to an imbalance of how these regions bias behavior because of differential engagement across different stages of development. -limbic and prefrontal system; -imbalance b/w the 2 -limbic system is stronger: more emotional behavior -as you get older- prefrontal region catches up and helps control limbic system -focusing on PFC region: has linier pattern of development, as you get older, it becomes better and better -limbic system: shows steeper slope initially, shoots up more quickly, more input of limbic system on behavior, earlier on development, greater difference b/w the 2 systems, lymbic regions will outpace pFC -teenagers may pay more attention to limbic system which is why they may be more emotional, reward-seeking b/c of the imbalance -by the time youre an adult and the lines level off, the systems are more parallel, emotion is equally regulated by pfc

Greebles

Train adults to expertise levels Greeble experts & novices higher FFA activity for Greeble experts -if we make people expert Greebles identifiers, will that show greater FFA activity -diff looks colors configurations -novel stimuli so no one has experience with it before FFA responds to other objects besides faces when the individual is an expert in the object -faces: both groups showed activations in FFA, only greeble experts showed activation of FFA when presented Greebles -not born with innate face response in FFA -we have become face experts and that's why -expertise region not face region

Metamorphosis

Under hormonal control Abrupt change in body structure (height, weight and shape) Change in behavior and mood much like puberty -once you have more than threshold of GnRH then jumpstarts puberty -no other time that you change as much as during puberty

Competence to proceed

Understanding Basic understanding of the purpose of the trial Reasoning Capacity to provide relevant information to counsel and process information Appreciation Ability to apply information to one's own situation in a manner that is neither distorted or irrational

(im)maturity

We use the word maturity synonymously with adulthood (age) Some characteristics of maturity: Intellectual curiosity, psychosocial skills, emotion regulation, perspective-taking, good decision-making skills ability to delay immediate gratification Maturity=competence (?) -there's not a 1 to 1 corresondence of being mature and being an adult -as adolescent -> adult high variety of maturity levels -if you treat someone in legal system, you are interested in whether they are competent

Why is adolescence important?

World leaders and health advocates have given increasing attention to the period of adolescence -such a growth b/w age range of 10-25 In 2015, the 3.1 billion people under the age of 25 represent about 42 percent of the world's total population. Africa, Asia and Latin America and the Caribbean are home to 90 percent of the world's young people: 1.7 billion youth aged 0-14 years old and 1.1 billion aged 15-24 years old. The number of young people are projected to grow to 3.4 billion by 2050. -big part of the population -in terms of public policy, health, they have the highest preventable death rate in adolescents besides elderly -contribute to economy both positively and negatively One function is to establish independence During this time, the brain and biological systems become more sensitive to certain kinds of experiences: - This creates risks as well as opportunities to support positive development and address some earlier negative experiences. - Can lead to the formation of life-long interests and passions. -sensitive to social development -risk taking: drugs, alcohol, sex -creates opportunity to learn about them in a protected way -things we're interested in adolescence can have life-long consequences and what we're drawn to later in life -emotions help you remember things so adolescence period can remember a lot vs. in your 30s -music preferences become cemented in adolescence -preferences for songs in 2012 vs 2008 differ based on gender -female preference is formed earlier, male preference is formed later in terms of teenagers and music preference -Low - flo Rida vs. -women : 11- 13 yrs old -men: 13-14 yrs old -puberty! -that's the way love goes highest rank for women 35 (11 at release) -just like -reminiscence bump: things around adolescence are very salient like songs, music -reminds you of friends, romantic times, -things more complicated than music will also have effect

Why do we need age-related laws?

Youth are unlikely to understand pleas or charges and more likely to confess -as you get older, less likely to confess, morelikely to remain silent -60% of 11-13 year olds confess, and may not be accurate, may be from fear, they think they will be forgiven for being honest, kids from ethnic minorities, boys are arrested more often 11-13 yrs old -as you get older, less likely to confess, morelikely to remain silent -60% of 11-13 year olds confess, and may not be accurate, may be from fear, they think they will be forgiven for being honest, kids from ethnic minorities, boys are arrested more often 11-13 yrs old -kids committing crime with 18+ kid are told to confess since they will be tried in juvie and not adult

Why do we need age-related laws?

Youth are unlikely to understand pleas or charges and more likely to confess Self-regulation is not yet mature in adolescence Adolescence is a developmental period with extensive variability (i.e. individual differences) Do teens understand the long-term consequences of their actions? -less likely to understand long-term consequences of their actions - Youth who are transferred from the juvenile court to the adult criminal systems are ~35% more likely than youth who stay in juvenile court to be re-arrested for violent or other crime. Most criminal activity by adolescents is "adolescence-limited" rather than "life-course persistent" -not true that adolescents commit more crimes than adults -some people who think adolescents should be treated as adults, b/c they think they will always be a criminal -data shows that -antisocial acts = criminal behabiors -only 10 % are career criminalts life=course persistent -most of people who commit crimes as adolescents are part of adolescent limited group, short window of time when they are committing these crimes, can age out of adolescent limited time, can grow out of criminal phenotype

What is policy?

a course or principle of action adopted or proposed by a government, party, business, or individual (e.g. plans, system, guidelines, position, attitude) Regarding adolescence, policymaking usually referring to education, legal system, age privileges -important for when youb ecome an adult because you are given new priveleges and rights Initial media attention on the adolescent brain was negative (2004-2006) More recent media coverage of the teen brain presents a more positive, adaptive view (2011-2012) -hormones make them impulsive and gets them into trouble, as society we should keep them isolated to protect them ( 2004-2006) -shift in narrative of adolescent brain dev. How does adolescent brain learn

Prosocial Behavior

any action intended to help others -is prosocial behavior ever truly altruistic? -if toddlers don't know yet that being helpful for someone they get something out of it, then they are a good model of studying prosocial behavior, examining if its instincual to help others Children as young as 14 months of age display spontaneous helping behavior -these kids show effort in terms of helping others -not only in easy cases -may be innate behaviors that we like helping other people -or It may be that it's learned -teenagers shift in who they want to help: they want to help peers, younger you want to help parents

Schools with later start times show:

extra sleep on school nights (ranging from 12 min to 1 hour) Better academic performance, mental health and safer driving -increases in SAT scores, less reckless driving -across the board schools have not adopted this -resistant because its challenging to implement huge policy shift

Are teens simply more influenced by the person of an other or does the identity of the other matter? Does the presence of an adult reduce peers' influence on risk-taking behavior?

target subjects were tested while being observed by 3 same-age male peers -more risk taking in adolecscents -same car task -slightly older confederates -presence of adults not that much older led to reduction in risk -25-30 years old - best age to serve as a buffer -same sex is influential too Peers may serve as a rewarding stimulus that sensitizes the motivational circuitry of the brain In the context of a relatively immature regulatory system, the reward system exhibits hyperactivation in teens relative to adults This may bias adolescents to follow their peers, particularly in the context of risk taking -pFC hasn't developed yet The adolescent reward system undergoes significant changes Puberty amplifies the reward sensitivity Rodent models of adolescence help us understand the neurobiology of greater reward sensitivity

What is social cognition?

the ability to use signals by members of the same species to navigate the world. Basic social cognitive skills: Face processing, affect processing, and joint attention Complex social cognitive skills: mentalizing, emotion processing, and interpersonal interactions The social brain: Neural regions that support social cognition are part of a socioemotional network Complex social cognitive skills: ability to take someone else's mind, understand what people are thinking about, good at doing this in membrs in same species

Historical pattern of technologically-related anxiety

-strong advocates against media use interferes with creativity, interaction with others, social cognitive skills -phones, tvs people considered with decrease of quality time Socrates even questioned the value of writing! -not a new idea to be afraid of new technology

More brain activation in the adolescent brain related to better learning

-surprise episodic memory test -is this an old pic or new pic (old pic means they saw it in the task) -better memory for images = higher correct responses -outside of the scanner -adolescents better at memory task when they received positive feedback than adults More brain activation in the adolescent brain related to better learning In adolescents only, brain activation correlated with episodic memory

"Reward Regions" Are Hyper-excitable In Adolescents

-adolescents show greater brain acitvations that kids or adults to same stimulus -adolescents value money more? -doesn't explain why kids don't show the same activation -has to do with how dopamine is being released during puberty

Delayed phase shift is not unique to humans

Around the time of puberty and independence-seeking in all species studied -different species -looking at magnittude of delay -humans 1-3 hrs -all other animals, juvinille animals also show sleep delay, not staying up for psychosocial regions, strictly biological -reminds us that even though adolescents seem to go to bed later because of psychological reasons Similarity across species 1-4 hr phase delay Correlation with puberty Suggests this phase delay is driven by biological mechanisms

Implications of Roper v. Simmons

Cancelled the death sentences of 72 juvenile offenders who were on death row (29 of those were in Texas) Strong use of scientific research revolutionalized the Court's use of empirical evidence to support its rulings

Overall Summary

Teens are not terrible The teen brain is very responsive to the environment in ways that is sometimes beneficial and sometimes harmful The teen brain is really good at learning from the environment and helping teens become independent and well-adjusted adults.

Strong activation in the reward system during winning compared to losing

for adolescents Peak in activation in the reward system during adolescence -peak acitvation between 15-20

After 1-month exposure to one species or another....

the monkeys maintained the ability to discriminate faces of the exposed species but had considerable difficulties in discriminating faces of the non-exposed species.