Week 9 Lecture 14 - intelligence, health and wellbeing Flashcards
What type of construct is intelligence?
latent –> can’t be measured directly
What is a recent definition of intelligence by Gottfredson (2000)
General ability to reason, plan, solve problems, think abstractly, learn quickly and learn from experience
What does IQ stand for?
Intelligence Quotient
What was IQ originally a measure of?
Originally a measure of deviation of mental age from chronological age:
- IQ = (mental age / chronological age) X 100
Wechsler (1975) redefined IQ to be what?
- A standardised score showing deviation from average score (of 100)
- Scores normally distributed with an SD of 15
Give some examples of intelligence test items
Digit span:
- “repeat each string of numbers in the order that I say it”
- start with short easy strings, then become longer and therefore more difficult
- can also ask to repeat string backwards
Letter number sequencing task:
- holding information in mind, reorganising it and presenting it back in a different way
- e.g., say numbers/letters first in ascending/ alphabetical order
- e.g., 8CJ2 –> 28CJ
Proverb task:
- interpret meaning of a proverb
- looks at abstract thinking
Trail-making task:
- measures speed of doing a task e.g., join circles in numerical order as fast as you can
Reasoning task:
- e.g., recognise pattern in a series of images and use this to determine what comes next in the sequence
What is G (general) intelligence?
- Charles Spearman (1863-1945)
- Common ‘mental energy’ underlying performance on all tests
- Indifference of the indicator –> g reflects something common to all types of mental ability task, it shouldn’t what test you use as they will all tell you something about that person underlying g intelligence
What is the hierarchy of intelligence?
- Assume a hierarchy of which G is at the top
- e.g., G, broad domains (i.e., working memory), task level (i.e., digit span)
- certain tests better measure certain domains
- no consenus on precise hierarchal structure/content
What level of intelligence are ID researchers and cognitive psychology researchers interested in?
ID –> g
CP –> broad domains
True or false
IQ correlates with academic achievement, job performance, and longevity
True
What is cognitive epidemiology?
- the examination of cognition/ IQ as a correlate of health and mortality
What are 2 important considerations in cognitive epidemiology?
- need to rule out reverse causation i.e., poor health can influence IQ
- confounding effects e.g., socio-economic status –> particularly in early life
What type of designs are used in cognitive epidemiology to establish causation?
longitudinal designs
What are the Scottish Birth Cohort Studies? What did Whalley and Deary (2001) do with this data?
- found dataset containing mental abilities of Scottish children –> tested entire nation with the same mental test
- tested children born in 1921 in 1932 and children born in 1936 in 1947
- Samples of these participants were traced and recruited into cohort studies
- 4 different cohorts recruited
What is the Morary House Test?
- 71 items including: Arithmetic,Reasoning etc.
- Scores correlate with Raven’s Matrices and Stanford-Binet.
- Valid measures of age 10/11 IQ.
- so data collected using this test can be used to investigate the influence of early life IQ on health and mortality/longevity
What was the method and results for the IQ and Longevity study by Whalley and Deary (2001)?
- Traced 2230 (80%) of ABC 1921 cohort.
- Compared childhood IQ scores of survivors (age 76yrs) vs. non-survivors.
- SES estimated by ‘overcrowding’ in childhood and father’s occupation
- Significant correlation between age-11 IQ and age of death after controlling for childhood SES (r=.19)
- larger effect of IQ for women than men and an earlier noticeable difference
- overlap/ almost reverse effect for men in teens/ early 20s –> corresponds with WW2. Men with lower IQ more likely to be rejected for active service.
Batty, Deary and Gottfredson (2007) conducted a systematic review where they tried to identify all cohort studies that measured early life IQ.
What did they find?
The 9 studies show that higher IQ in first 20 years of life is linked with lower mortality, even after adjusting for childhood SES
What are the 4 causal mechanisms that have been proposed for the link between IQ and health?
- High IQ confers a survival advantage because it makes you more likely to have a higher SES as an adult and thus benefit from all the health advantages that this brings
- High IQ = likely to have high health literacy. Use this to make sensible decisions about health and then engage in health seeking behaviours e.g., follow medication regimes, exercise, wear a seatbelt
- Suboptimal neural development (pre or peri natal) limits cognitive ability (lowers IQ) but also makes them more vulnerable to psychiatric conditions –> can have negative impact on general health
- evidence: low IQ associated with psychiatric disorders. BUT controlling for BW does not eliminate IQ-longevity links
- High IQ is a more general marker of body system integrity and therefore more likely to live longer
- evidence: body symmetry is a marker with general health and fitness and is associated with IQ
What might the contribution of the 4 causal mechanisms that have been proposed for the link between IQ and health vary depending on?
- all mechanisms may help explain link
- contribution of each mechanism may vary by cause of death
A study by Ali et al. (2013) look at intelligence and happiness.
What was their reasoning and method for this study?
- Mixed results from previous studies
- Representative sample of 7403 English adults.
- Measured Happiness.
- Verbal IQ measured with National Adult Reading Test (NART).
- Measured potential mediating variables that may account for any IQ-happiness relationship
A study by Ali et al. (2013) look at intelligence and happiness.
What were their results?
- High IQ predicted likelihood of being happy
Relationship mediated by:
- Dependency in Activities of Daily Living
- Income
- Neurotic Symptoms
- Self-reported Health
- Marital status
- Social participation
- Further studies needed to test mechanisms longitudinally
