Child Flashcards
Intelligence
Problems with IQ tests
Cultural bias
Only focus on childs interlectual abilities
Intelligence
Biological factors affecting intelligence
Pre-natal malnutrition
Pre-natal exposure to smoking/alcohol/drugs
Intelligence
Van Leeuwen: Aim
To carry out an extended twin study which would consider the assumptions previously overlooked
to test which model (phenotypic assortment/social homogamy) is better explanation for IQ
whether nature/nurture affects IQ more
to calculate unbiased heritability estimate for IQ
Intelligence
Van Leeuwen: Participants
112 families selected from Netherlands Twin Registry w a pair of twins + additional sibling
48 MZ twin pairs, 64 DZ
mean age twins 9.1, mean age sibling 11.9
Intelligence
Van Leeuwen: Procedure
Tested at Free University of Amsterdam, children and parents tested in groups in separate rooms, took 5 hours inc breaks
Twin status established w cheek swabs to determine zygosity, standardised procedure
Intelligence
Van Leeuwen: Results
No sig diff males and females
Significance larger variabilities for siblings - could be as siblings older
Correlations higher between MZ twins
heritability estimate 67%, random environmental effects 33%
Intelligence
Van Leeuwen: Conclusion
Phenotypic assortment greater influence, intelligence best explained by additive genetic effects rather than environmental factors
Cultural transmission not significant except in children w genetic predisposition for low IQ compared to children w genetic predisposition for high IQ
Intelligence
Application: Intelligence
Assessing intelligence - Raven’s progressive matrices
Pre-adult brain development
Stages of brain development
Sensori-motor: (0-2) - Use of 5 senses
Pre-operational: (2-7) - Mental representation
Concrete-operational: (7-11) - Perspectives and problem-solving
Formal-operational: (11+) - Abstract and hypothetical thinking
Pre-adult brain developemnt
Barkley-Levenson & Galvan: Aim
To investigate if there are biological and behavioural differences between adults and adolescents with gambling
Pre-adult brain developement
Barkley-Levenson & Galvan: Participants
Adults
19 (11f 8m)
right handed
from the USA
aged between 25 and 30
Adolescents
22
right handed
13-17 year olds
11f 11m
Pre-adult brain development
Barkley-Levenson & Galvan: Procedure
Intake session
informed consent given by adults/parents
gave details of monthly spending money and where it came from, sig diff between adults and adolescents
at end given $20 to use as playing money
fMRI session
pps shown spinner in scanner, divided into 2 halves showing gain and loss, pp had to decide whether to accept gamble or not
192 trials/pp, 24 trials - only outcome was gain, 24 trials - only outcome was loss
choosing to gamble on fixed trials didn’t indicate risk taking
at end of trial, one gamble was taken at random for real money
Pre-adult brain developemnt
Barkley-Levenson & Galvan: Results
Increasing EV made acceptance more likely, more sig in adolescents
No effect of disposable income, no change in gamble acceptance for adols or adults in fixed trials
as EV increased, activity in superior medial PFC increased, activity in amygdala and hc decreased
adols greater activation in left VS than adults
Analysed data from pps w high rate of gambling acceptance (>80%) on high EV trials - difference in VS activation remained
Pre-adult brain development
Barkley-Levenson & Galvan: Conclusion
Adolescent brain shows heightened response to rewards
Unique adolescent response to reward is genuine phenomenon due to greater value placed on rewards
Pre-adult brain developement
Application: Driving
Graduated driver licensing programme: speed, passengers, curfew
