Studies show that the correlations of IQ scores for identical twins reared together and for identical twins reared apart are both strong (. … However, the score correlations for fraternal twins also suggests that
the environment in which they were raised is significant for IQ
.
What do twin studies tell us about the importance of genetics on intelligence quizlet?
Twin studies reveal that: the influence of genetics on IQ
is most visible at young ages
. genetic influences on IQ increase with age. correlations between twins' IQ scores decrease with age for MZ (identical) twins and increase with age for DZ (fraternal) twins.
What do twin studies tell us about intelligence?
Genes have a very strong influence over how certain parts of our brains develop
, scientists in the US and Finland have found. In identical twins, these areas showed a 95 to 100 per cent correlation between one twin and the other – they were essentially the same. …
What do twin studies determine?
Twin studies allow researchers to
examine the overall role of genes in the development of a trait or disorder
. Comparisons between monozygotic (MZ or identical) twins and dizygotic (DZ or fraternal) twins are conducted to evaluate the degree of genetic and environmental influence on a specific trait.
What did twin studies conclude?
Modern twin studies have concluded that
almost all traits are in part influenced by genetic differences
, with some characteristics showing a stronger influence (e.g. height), others an intermediate level (e.g. personality traits) and some more complex heritabilities, with evidence for different genes affecting …
What are the advantages of twin studies?
Advantages of twin studies
Twin studies
allow disentanglement of the shared genetic and environmental factors for the trait of interest
. Researchers can estimate the proportion of variance in a trait attributable to genetic variation versus the proportion that is due to shared environment or unshared environment.
Why are twin studies unethical?
The study, which has since been criticized for being unethical — for example, neither the children's biological parents nor the adopting families were informed — was an attempt to get at the central psychological questions of “nature versus nurture” and the “twinning reaction.”
What do twin studies tell us about intelligence quizlet?
What do twin studies tell us about IQ? …
Finding that average IQ scores have been rising at a rate of approximately 3 points per decade
– Due to increased sophistication of IQ tests, increased complexity of the modern world, better nutrition, changes at home and school, etc.
What have twin studies revealed about intelligence quizlet?
What have twin studies revealed about intelligence?
Intelligence is partly influenced by heredity
. A psychologist is developing a theoretical explanation about a behavior.
Which is the highest heritability score?
A high heritability,
close to 1
, indicates that genetics explain a lot of the variation in a trait between different people; a low heritability, near zero, indicates that most of the variation is not genetic.
What are the problems with twin studies?
The most common objections to twin studies have been: (1)
Twins have almost always been reared to- gether
and this common rearing may have con- tributed to increased concordance in monozygotic (MZ) twins because of psychological characteris- tics unique to such pairs (8, 29);
Why are studies of identical twins raised in different environments extremely valuable?
Why are studies of identical twins raised in different environments extremely valuable in understanding the causes of a disease? They are extremely valuable in understanding the causes of a disease, because it
differentiates
between nature vs. nurture.
Do twins have the same fingerprints?
Even identical twins – who have the same DNA sequence and tend to share a very similar appearance –
have slightly different fingerprints
. That's because fingerprints are influenced by both genetic and environmental factors during development in the womb. … But fingerprints are not unique to humans.
Is schizophrenia more common in twins?
Previous studies show that
schizophrenia affects both members of identical twins in 41% to 61% of cases
, but only 0 to 28% in non-identical twins. A previous pooling of twin studies has suggested that the “heritability” of schizophrenia is 81%.
Which of the following is a limitation of twin studies?
Which of the following is a limitation of twin studies?
The samples are not representative
. (Twins lead a very different life than the average child growing up. Therefore, they are not highly representative.
Who was the first person to study twins?
The twin method is usually credited to
Francis Galton's
1875 article on twins. However, Galton did not propose the comparison between identical and fraternal twin resemblance which is the essence of the twin method.
