Personality Psychology (Chapter Seven)

theoretical bridge

The connection between two variables.

free running

A condition in studies of circadian rhythms in which participants are deprived from knowing what time it is. When a person is free running in time, there are no time cues to influence behavior or biology.

sensation seeking

A dimension of personality postulated to have a physiological basis. It refers to the tendency to seek out thrilling and exciting activities, to take risks, and to avoid boredom.

norepinephrine

A neurotransmitter involved in activating the sympathetic nervous system for flight or fight.

dopamine

A neurotransmitter that appears to be associated with pleasure. Dopamine appears to function something like the "reward system" and has even been called the "feeling good" chemical.

serotonin

A neurotransmitter that plays a role in depression and other mood disorders. Drugs such as Prozac, Zoloft, and Paxil block the reuptake of serotonin, leaving it int he synapse longer, leading depressed persons to feel less depressed.

alpha wave

A particular type of brain wave that oscillates 8 to 12 times a second. The amount of alpha wave present in a given time period is an inverse indicator of brain activity during that time period. The alpha wave is given off when the person is calm and relaxed. In a given time period of brain wave recording, the more alpha wave activity present the more we can assume that part of the brain was less active.

impulsivity

A personality trait that refers to lowered self-control, especially in the presence of potentially rewarding activities, the tendency to act before one thinks, and a lowered ability to anticipate the consequences of one's behavior.

electrodes

A sensor usually placed on the surface of the skin and linked to a physiological recording machine (often called a polygraph) to measure physiological variables.

cortisol

A stress hormone that prepares the body to flee or flight. Increases in cortisol int he blood indicate that the animal has recently experienced stress.

ascending reticular activating system (ARAS)

A structure in the brain stem thought to control overall cortical arousal. The structure Eysenck originally thought was responsible for the differences between introverts and extroverts.

type A personality

An action-emotion complex that can be observed in any person who is aggressively involved in a chronic, incessant struggle to achieve more and more in less and less time and if required to do so against opposing efforts of other things or other persons. Type A refers to a syndrome of several traits: achievement motivation and competitiveness, time urgency, and hostility and aggressiveness.

monoamine oxidase (MAO)

An enzyme found in the blood that is known to regulate neurotransmitters, those chemicals that carry messages between nerve cells. MAO may be a causal factor in the personality trait of sensation seeking.

anxiety

An unpleasant, high-arousal emotional state associated with perceived threat. Psychoanalytically, anxiety is seen as a signal that the control of the ego is being threatened by reality, impulses from the id, or harsh control exerted by the superego. Freud first identified three different types of anxiety: neurotic anxiety, moral anxiety, and objective anxiety. Carl Rogers understood anxiety as being the unpleasant emotional state resulting from having an experience that does not fit with one's self-conception.

frontal brain asymmetry

Asymmetry in the amount of activity in the left and right part of the frontal hemispheres of the brain. Studies using EEG measures have linked more relative left brain activity with pleasant emotions and more relative right brain activity with negative emotions.

neurotransmitters

Chemicals in the nerve cells that are responsible for the transmission of a nerve impulse from one cell to another. Some theories of personality are based directly on different amounts of neurotransmitters found in the nervous system.

tridimensional personality model

Cloninger's tridimensional personality model ties three specific personality traits to the levels of 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.

electrodermal activity

Electricity will flow across the skin with less resistance if that skin is made damp with sweat. Sweating on the palms of the hands is activated by the sympathetic nervous system and so electrodermal activity is a way to directly measure changes in the sympathetic nervous system.

reinforcement sensitivity theory

Gray's biological theory of personality. Based on recent brain function research with animals, Gray constructed a model of human personality based on two hypothesized systems in the brain: the behavioral activation system (which is responsible to incentives, such as cues for reward, and regulates approach behavior) and the behavioral inhibition system (which is responsive to cues for punishment, frustration, and uncertainty)

optimal level of arousal

Hebb believed 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. By optimal level of arousal, Hebb meant a level that is just right for any given task.

harm avoidance

In Cloninger's tridimensional personality model, the personality trait of harm avoidance is associated with low levels of serotonin. People low in serotonin are sensitive to unpleasant stimuli or to stimuli or events that have been associated with punishment or pain. Consequently, people low in serotonin seem to expect that harmful and unpleasant events will happen to them and they are constantly vigilant for signs of such threatening events.

novelty seeking

In Cloninger's tridimensional personality model, the personality trait of novelty seeking is based on low levels of dopamine. Low levels of dopamine create a drive state to obtain substance or experiences that increase dopamine. Novelty and thrills and excitement can make up for low levels of dopamine and so novelty-seeking behavior is thought to result from low levels of this neurotransmitter.

reward dependence

In Cloninger's tridimensional personality model, the personality trait of reward dependence is associated with low levels of norepinephrine. People high on this trait are persistent: They continue to act in ways that produced reward. They work long hours, put a lot of effort into their work, and will often continue striving after others have given up.

circadian rhythms

Many biological processes fluctuate around an approximate 24-25 hour cycle. These are called circadian rhythms. Circadian rhythms in temporal isolation studies have been found to be as short as 16 hours in one persons and as long as 50 hours in another person.

sensory deprivation

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 use sensory deprivation chambers to see what happens when a person is deprived of sensory input.

electroencephalograph (EEG)

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

cardiac reactivity

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

physiological systems

The organ systems within the body. ex. nervous system, the musculoskeletal system.

arousal level and arousability

The original theory of extroversion held that extroverts had lower levels of cortical or brain arousal than introverts. More recent research suggests that the difference between introverts and extroverts lies more in the arousability of their nervous systems, with extroverts showing less arousability or reactivity than introverts to do the same levels of sensory stimulation.

autonomic nervous system

The part of the peripheral nervous system that connects to vital bodily structures associated with maintaining life and responding to emergencies such as the beating of the heart, respiration, and controlling blood pressure. There are two divisions of the ANS: the sympathetic and the parasympathetic branches.

comorbidity

The presence of two or more disorders of any type in one person.

telemetry

The process by which electrical signals are sent from electrodes to a polygraph using radio waves instead of wires.

morningness-eveningness

The stable differences between persons in preferences for being active at different times of the day. The term was coined to refer to this dimension. Differences between morning and evening types of persons appear to be due to differences in the length of their underlying circadian biological rhythms.

behavioral inhibition system (BIS)

The system 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.

behavioral activation system (BAS)

The system that is responsive to reward incentives, such as cues for reward, and regulates approach behavior. When some stimulus is recognized as potentially rewarding, the BAS triggers approach behavior. This system is highly correlated with the trait of extroversion.