Personality Psychology: Chapter 6

True or false: In relation to genotypic variance, a heritability of .50 means that 50 percent of the observed phenotypic variation is attributable to genotypic variation.

true

Behavioral geneticists typically are not content simply with figuring out the ____ due to genetic and environmental causes

percentage of variance

generally speaking, the larger the heritability, the smaller the

environmentality

______ is a statistic that refers to the proportion of observed variance in a group of individuals that can be accounted for by genetic variance.

heritability

a common misconception about heritability is that is:

can be applied to a single individual

Genetic researchers are discovering that parts of the 98 percent of DNA, other than the 2 percent that make up protein-coding genes, _____

have an impact on humans

Heritability is a statistic that applies only to:

a population at one point in time and in a particular array of environments.

______ refers to observed individual differences.

phenotypic variance

Heritability is best regarded merely as a(n) ______ of the percentage of phenotypic differences due to genetic differences.

estimate

______ refers to individual differences in the total collection of genes possessed by each person.

genotypic variance

The percentage of observed variance in a group of individuals that can be attributed to environmental differences is called

environmentality

Clarifying the meaning of the term heritability—what it is and what it is not—allows researchers to think more clearly about the:

nature-nurture debate

Heritability refers only to:

differences in a sample or population

One common misconception about heritability is that it is:

constant

A final common misconception about heritability is that it:

is an absolutely precise statistic

The arguments about whether genes or environments are more important determinants of personality are known as the:

nature-nurture debate

At the level of analysis of population, a clear understanding of the nature-nurture debate is attained by:

disentangling the influence of genes and environments.

A common misconception about heritability is that it:

can be applied to a single individual.

______ can take place only if the desired characteristics are under the influence of heredity.

artificial selection

___ ____ capitalize on the fact that there are known degrees of genetic relatedness among family members.

family studies

_____ _____ estimate heritability by gauging whether identical twins are more similar to each other than are fraternal twins.

twin studies

Twins that come from a single fertilized egg, which divides into two at some point during gestation are called:

monozygotic twins

True or false: At the population level of analysis, it is impossible to partition the differences in traits into two sources: differences in genes and differences in environments.

false

By identifying the dogs that possess the desired characteristic and having them mate only with other dogs that also possess the characteristic, ____ occurs

selective breeding

unlike fraternal twins, identical twins

are generally of the same sex

___ ___ correlate the degree of genetic relatedness among family members with the degree of personality similarity

family studies

fraternal twins are also called

dizygotic twins

______ take advantage of a fascinating quirk of nature. Nearly all individuals come from a single fertilized egg, and humans—as contrasted with some other mammals, such as mice—typically give birth to a single child at a time.

twins studies

the twin method makes the ____ ____ ___ that states that the environments experienced by identical twins are no similar to each other than are the environments experienced by fraternal twins

equal environments assumption

In __________ ___________, one can examine the correlations between adopted children and their adoptive parents, with whom they share no genes.

adoption studies

If researchers find a positive correlation between adopted children and their adoptive parents, then this provides strong evidence for ______ on the personality trait in question.

environmental influences

In adoption studies, genetic parents provide none of the environmental influences on their children as in twin studies, thus:

unconfounding genetic and environmental causes.

The most important potential problem of adoption studies is the:

assumption of representativeness

One of the most powerful behavioral genetic methods available is:

adoption studies

If researchers who conduct adoption studies inflate correlations between the adopted children and their adoptive parents by placing them with adopted parents who are similar to their birth parents, it will result in the potential problem of

selective placement

If researchers find a positive correlation between parents and their adopted-away children, with whom they have had no contact, then this provides evidence for:

heritability

In the context of behavioral genetic methods, adoption studies are especially powerful because:

they allow researchers to get around the equal environments assumption.

extraversion

A dimension containing people who are outgoing and talkative at one end and people who are quiet and withdrawn at the other end.

Neuroticism

A dimension with one end characterized by people who are anxious, nervous, and emotionally volatile and at the other end calm and emotionally stable.

twins tudies

moderate heritability

adoption studies

low heritability

Adoption studies assume that adopted children, their birth parents, and their adoptive parents:

are representative of the general population.

Individual differences in the trait of ___ have been subjected to behavioral genetic analysis

activity level

Longitudinal studies of adopted and non-adopted children reveal that values show:

moderate heritability

The most commonly studied personality traits in behavioral genetic designs are ____ and _____

extraversion and neuroticism

______ are often regarded as behavioral manifestations of personality dispositions, such as sensation seeking, extraversion, and neuroticism.

drinking and smoking

In the context of studies of the personality traits of Extraversion and Neuroticism, correlations between adoptive parents and their adopted children tend to be around zero, suggesting:

little direct environmental influence on these traits.

True or false: A genetic proclivity to marry occurs only through heritable personality traits that are desired by potential marriage partners.

false

the most important potential problem of adoption studies is that

assumption of representativeness

Individual differences in the trait of activity level shows:

a moderate degree of heritability

______ show wide individual differences, tend to be stable over time, and are sometimes linked with actual behavior.

stable attitudes

Individuals differ widely in their smoking and drinking habits, and these differences tend to:

be stable over time

One causal path through which heritability could influence the propensity to marry is through:

personality characteristics

Shared environment

The number of books in the home; the presence or absence of a TV, DVD player, or computer and the parents' values and attitudes.

Nonshared environment

Special treatment from parents, occupying different rooms in the house, and different groups of friends.

Zack performs well on tasks even when there is no stimulation in the room. However, he performs poorly when there are distractions such as loud music. In contrast, Mia performs exceedingly well even where there is loud music and makes more errors in the absence of stimulation. The differences between Zack and Mia can be attributed to:

genotype-environment interaction

the differential exposure of individuals with different genotypes to different environments is known as

genotype environment correlation

______ occurs when parents provide both genes and the environment to children, yet the children do nothing to obtain that environment.

Passive genotype-environment correlation

the differential response of individuals with different genotypes to the same environments is known as

genotype environment interaction

the ______ occurs when parents or others respond to children differently, depending on the child's genotypes.

reactive genotype-environment correlation

____ occurs when a person with a particular genotype creates or seeks out a particular environment

active genotype-environment correlation

Joseph's parents notice that he is athletically inclined, and they encourage Joseph to take part in sports activities in his school and in the neighborhood. This scenario illustrates:

genotype-environment correlation.

Jim's parents are highly sociable and have passed on their genes to him, which makes him highly sociable. However, because his parents are highly sociable, they host a number of parties and social gatherings at home. Jim has done nothing to initiate these gatherings. This is an illustration of the:

passive genotype-environment correlation.

The most recent development in the science of behavioral genetics has been the exploration of

molecular genetics

the ______ method of molecular genetics is used to identify whether individuals with a particular gene have higher or lower scores on a particular trait than individuals without the gene.

association

Annie and Sophie are twins. Annie enjoys social stimulation and loves being around people, in contrast to her sister Sophie. During family gatherings, their parents involve Annie in all the activities and seek her help. They do not approach Sophie as they know she does not enjoy it. This scenario is an illustration of:

reactive genotype-environment correlation.

______ highlights the fact that individuals mold, create, and select the environments they subsequently inhabit, and some of these actions are correlated with their genotypes.

Active genotype-environment correlation