Personality of Psyc Exam 2

fMRI

A noninvasive imaging technique used to identify specific areas of brain activity. As parts of the brain are stimulated, oxygenated blood rushes to the activated area, resulting in increased iron concentrations in the blood. The fMRI detects these elevated concentrations of iron and prints out colorful images indicating which part of the brain is used to perform certain tasks.

Active

A person with a particular genotype creates or seeks out a particular environment

Electrodermal activity (EDA)

Also known as galvanic skin response or skin conductance, it refers to the fact that electricity will flow across skin with less resistance if that skin is made damp with sweat. Seating on the palms of the hands is activated by the sympathetic nervous system, and so EDA is a way to directly measure changes in the SNS.

Biochemicals

Analysis of blood and saliva. Also measure hormones such as testosterone (linked to uninhibited, aggressive, and risk-taking behavior), cortisol (a by-product of noradrenaline and found in saliva), and monoamine oxidase (found in blood, regulates neurotransmitters, may link to sensation seeking)

Problem with adoption studies

Assumption of representativeness- adoptive parents cannot represent the general population. Selective placement- if adopted children are placed with adoptive parents who are similar to their birth parents, this may inflate the correlations between the adopted children and their adoptive parents. In this case, the resulting inflated correlations would artificially inflate estimates of environmental influence since the correlation would appear to be due to the environment provided by the adoptive parents. There does not seem to be selective placement, and so this potential problem is not a problem in actual studies.

BIS/BAS

BAS- in Gray's reinforcement sensitivity theory, Behavioral Activation System is the system that is responsive to incentives, such as cues for reward, and regulates approach behavior. When some stimulas is recognized as potentially rewarding, the BAS triggers approach behavior. This system is highly correlated with the trait of extraversion. BIS- In Gray's reinforcement sensitivity theory, the Behavioral Inhibition System is responsive to cues for punishment, frustration, and uncertainty. The effect of BIS activation is to cease or inhibit behavior or to bring about avoidance behavior. This system is highly correlated with the trait of neuroticism.

Cloninger's Tridimensional Model of personality

Cloninger's TPM ties three specific personality traits to levels of the three neurotransmitters. The first trait is called novelty seeking and is based on low levels of dopamine. The second personality trait is harm avoidance, which he associates with low levels of serotonin. The third trait is reward dependence, which Cloninger sees as related to low levels of norepinephrine

Family studies

Correlate that degree of genetic overlap among family members with the degree of personality similarity. They capitalize on the fact that there are known degrees of genetic overlap between different members of family in terms of degree of relationship.

Darwin's Theory of Evolution by Natural Selection

Darwin reasoned that variants that better enabled an organism to survive and reproduce would lead to more descendants. The descendants, therefore, would inherit the variants that led to their ancestors' survival and reproduction. Through this process, the successful variants were selected, and unsuccessful variants weeded out. Natural selection, therefore, results in gradual changes in a species over time, as successful variants increase in frequency and eventually spread throughout the gene pool, replacing the less successful variants.

Twin studies

Estimate heritability by gauging whether identical twins, who share 100% of their genes, are more similar to each other than fraternal twins, who share only 50% of their genes. Twin studies, and especially studies of twins reared apart, have received tremendous media attention.

Adoption studies

Examine the correlations between adopted children and their adoptive parents, with whom hey share no genes. These correlations are then compared to the correlations between the adopted children and their genetic parents, who had no influence on the environments of the children. Differences in these correlations can indicate the relative magnitude of genetic and environment contributions to personality traits.

Hebb's theory of optimal arousal

Hebb's believe that people are motivated to reach an optimal level of arousal. If they are underaroused relative to this level, an increase in arousal is rewarding; conversely, if they are overaroused, a decrease in arousal is rewarding

Heritability vs. environmentality

Heritability- a statistic that refers to the proportion of observed variance in a group of individuals that can be explained or "accounted for" by genetic variance. It describes the degree to which genetic differences between individuals cause differences in some observed property, such as height, extraversion, or sensation seeking. Environmentality- the percentage of observed variance in a group of individuals that can be attributed to environmental (nongenetic) differences. The larger the heritability, the smaller the environmentality (and vice versa).

Adaptation

Inherited solutions to the survival and reproductive problems posed by the hostile forces of nature. Adaptations are primary product of the selective process. An adaptation is a "reliably developing structure in the organism, which because it meshes with the recurrent structure of the world, causes the solution to an adaptive problem"

Intersexual & Intrasexual competition

Intersexual selection- members of one sex choose a mate based on their preferences for particular qualities in that mate. These characteristics evolve because animals that possess them are chosen more often as mates, and their genes thrive. Animals that lack the desired characteristics are excluded from mating, and their genes perish. Intrasexual competition- members of the same sex compete with each other, and the outcome of their contest gives the winner greater sexual access to members of the opposite sex. Two stags locking horns in combat is the prototypical image of this. The characteristics that lead to success in contests of this able to mate more often and hence pass on more genes.

Brain activity

Measured using an EEG, Evoked potential technique, PET scans, and fMRI

Evolutionary perspectives on aggression

Men are more aggressive and more likely to commit homicide.

Research findings regarding jealousy

Men are more upset about sexual infidelity and women are more upset about emotional infidelity. Few women are uncertain about which children are their own, but it is not the same for men. A man having sex with another woman would not change the fact that the baby is hers, but it would take away the man's resources being provided to the woman.

Hamilton's Inclusive Fitness Theory

Modern evolutionary theory, which is based on differential gene reproduction. The "inclusive" part refers to the fact that the characteristics that people affect reproduction need not affect the personal production of offspring: they can affect the survival and reproduction of genetic relatives as well

Monozygotic vs. Dizygotic twins

Monozygotic- Identical twins that come from a single fertilized egg that divides into two at some point during gestation. Identical twins are always the same sex because they are genetically identical Dizygotic- AKA fraternal twins, are not genetically identical. They come from two eggs that were separately fertilized. These twins only share 50% of their genes, like ordinary brothers and sisters.

Evolutionary perspectives of individual differences

Noise or random variation, individual music preferences

Sensory deprivation research

Often done in a sound-proof chamber containing water in which a person floats, in total darkness, such that sensory input is reduced to a minimum. Researchers used sensory deprivation chambers to see what happens when a person is deprived on sensory input.

Eysenck's original theory and how it changed w/physiological research

Original theory- everyone has their own ideal level of arousal. Introverts need less arousal and avoid stimulation and extroverts need more arousal and seek out simulation. Revised theory- research showed at resting levels introverts and extroverts don't differ. Introverts are more reactive to stimulation.

Reactive

Parents (or others) respond to children differently, depending on their genotype

Passive

Parents provide both genes and environment to children, yet the children do nothing to obtain that environment

PET

Positron emission tomography- a noninvasive imaging technique used for mapping the structure and function of the brain.

Proximate vs. ultimate explanations for behavior

Proximate- why does it happen here and now? Example- the need to belong, it feels good to have friends and bad to be alone Ultimate- why does it happen at all? Example- need to belong in the ancient world because without others you would not survive

Patterns of arousal for morning vs. evening people

Refers to stable differences between persons in preferences for being active at different times of the day. Differences between morning and evening types of persons appear to be due to differences in the length of their underlying circadian biological rhythms

Genotype-environment correlations

Refers to the differential exposure of individuals with different genotypes to different environments

Genotype-environment interaction

Refers to the differential exposure of individuals with different genotypes to the same environments

Selective breeding

Researchers identify a trait and then see if they can selectively breed animals to possess that trait. This can only occur if the trait has a genetic basis. For example, dogs that possess certain desired characteristics, such as sociable disposition, might be selectively bred to see if this disposition can be increased in frequency among offspring. Traits that are based on learning cannot be selectively bred for.

Basic principles of natural selection and sexual selection

Sexual selection- the evolution of characteristics because of their mating benefits, rather than because of their survival benefits. Sexual selection takes two forms: intersexual and Intrasexual

Shared & Nonshared environmental influences

Shared environment- features of the environment that siblings share, for example, the number of books in the home, the presence of absence of a tv and vcr, quality and quantity of the food in the home, the values and attitudes of the parent, and the schools, church, synagogue, or temple the parents send the children to. Nonshared environment- features of the environment that siblings do not share. Some children might get special or different treatment from their parents, they might have different friend groups, they might be sent to different schools, or one might go to summer camp which the other stays home each summer.

Correlation between sensation seeking and extraversion

Strong positive correlation, Zuckerman's finding showed that high sensation seekers have a need for high levels of stimulation in their daily lives.

Molecular genetics

Techniques designed to identify the specific genes associated with specific traits, such as personality traits.

Evoked potential technique

The brain EEG is measured but the participant is given a stimulus, such as a time or a flash of light, and the researcher assesses the participant's brain responsiveness to the stimulus.

EEG

The brain spontaneously produces small amounts of electricity, which can be measured by electrodes placed on the scalp. EEGs can provide useful info about patterns of activation in different regions of the brain that may be associated with different types of information processing tasks

Byproduct of an adaptation

The evolutionary process produces mechanisms that are not adaptations, but rather are by-products of other adaptations. Our nose, for example, is clearly an adaptation designed for smelling. But the fact that we use our nose to hold up our eyeglasses in an incidental by-product

D4DR gene

The gene located on the short arm of chromosome 11. This gene codes for a protein called a dopamine receptor. The function of this dopamine receptor is to respond to the presence of dopamine, which is a neurotransmitter. When the dopamine receptor encounters dopamine form other neurons in the brain, it discharges an electrical signal, activating other neurons.

Cardiac reactivity

The increase in blood pressure and heart rate during times of stress. Evidence suggests that chronic cardiac reactivity contributes to coronary artery disease.

Eugenics

The notion that the future of the human race can be influenced by fostering the reproduction of persons with certain traits, and discouraging reproduction among persons without those traits or who have undesirable traits

Random variation

The shape of the human earlobe, everyone's is different but they do not affect the basic functioning of the ear

Discord

What was adaptive in the past may not be adaptive now. For example, in the ancient world they would crave high fat foods because it was limited but now it is not