[CHILD 2] BARKLEY, LEVENSON & GALVAN

AIM: to see whether adolescents value __ more than adults

Rewards

AIM: to identify regions of the brain involved in judging __ and __

Rewards, values

SAMPLE: __ adults, __ adolescents , all healthy and right-handed

19, 22

SAMPLING TECHNIQUE:

Self selected

RESEARCH METHOD:

Quasi lab experiment

DESIGN:

Matched pair

IV:(2)

Adolescent or adult

DV:(2)

Neural activation and behavioural data

How data was gathered:

Observation and scientific equipment

1. Participants gave __

Consent

2. Participants were given a __ __ __ to get used to the FMRI

Mock brain scan

3. Collected data on pps __ __, so they could make sure brain activation wasn’t due to just not being used to having money

Monthly income

4. Gave the pps $20 and instructed to come back a __ later, to increase pps feeling that they owned $20

Week

5. Told they could win up to another whole $20 and lose up to __

$20

6. Pps were given a series of __ 50/50 bets, and had to indicate whether they would be happy taking the bet

144

7. They were told at the __ __ __, one of their chosen gambles would actually be carried out, and they might win more money or lose some of their $20

End of the study

8. Pps are shown 144 50/590 trials, whilst in the __

FMRI

We can work out an expected value for each of these: the sum of all of the __ __ of a particular choice multiplied by their __

Possible outcome, probabilities

NEURAL RESULTS: fMRI results showed the higher the __ the greater the activation in the ventral striatum in both adults and adolescents

EV

NEURAL RESULTS: Adolescents had greater activation at high EV’s than adults, in the __ __

Ventral striatum

NEURAL RESULTS: Even when adults and adolescents were equally likely to gamble, the ventral striatum activated more in __, showing a greater processing of tempting stimuli

Adolescents

BEHAVIOURAL RESULTS: Across all pps trials with positive EV were accepted significantly __ than trials with EV of zero, which were accepted significantly __ than trials with negative EV

More, more

BEHAVIOURAL RESULTS: No __ __were observed between adolescent and adult pps in the percentage of EV+, EV zero and E- trials accepted

Significant differences

BEHAVIOURAL RESULTS: Adolescents were more likely to gamble at __ __ than adults

Higher EV’s

CON: Adolescents place greater __ _ __ than adults do

Value on reward

CON: The __ __ is more active in adolescents than adults

Ventral striatum

CON: There may be an __ __, as adolescents need to take new risks and try new situations in order to explore, find new mates and independence

Evolutionary advantage