Problem 4: Personality and the Brain Flashcards
Neurotransmitters
= biochemical substances involved in the communication among nerve cells, or neurons
–> can act in such a ways as to speed up the communication of messages from one neuron to the next, or to slow down that communication
–> the “firing” of neurons is the basis of our emotions, our thoughts, and our behaviors
Dopamine
Facilitates response to pleasurable, exciting stimuli
–> associated with Extraversion and Openness
–> involved in motivation, emotion, and reward
–> involved in higher cognition (PFC)
Serotonin
Inhibits response to harmful, unpleasant stimuli
–> associated with Neuroticism, Agreeableness, or Conscientiousness
–> low levels: aggression, poor impulse control, and depression
Norepinephrine
Inhibits response to stimuli that have previously been associated with pleasure –> inhibits signals of conditioned reward
Tridimensional Personality Model - Cloninger
Dopamine and Novelty Seeking
Individuals whose dopamine system is very active will tend to have high levels of “Novelty Seeking”
–> the tendency to seek pleasure and excitement
Individuals whose dopamine system is very inactive will den to be low in Novelty Seeking
–> they will not be particularly motivated to find fun and variety
Tridimensional Personality Model - Cloninger
Serotonin and Harm Avoidance
Individuals whose serotonin system is very inactive will tend to have high levels of “Harm Avoidance”
–> the tendency to avoid pain and anxiety
Individuals whose serotonin system is very active will tend to be low in Harm Avoidance
–> they will not be particularly motivated to avoid pain and anxiety
Tridimensional Personality Model - Cloninger
Norepinephrine and Reward Dependence
Individuals whose norepinephrine system is very inactive tend to have high levels of “Reward Dependence”
–> the tendency to develop strong sentimental attachments
Individuals whose norepinephrine system is very active will tend to be low in Reward Dependence
–> they will tend not to develop strong sentimental attachments
Reinforcement Sensitivity Theory - Gray
Behavioral Activation System (BAS)
= regions from the brain that are responsible for receiving signals from the nervous system which indicate that rewards are being experienced (or are about to be experienced)
–> “go” system - encourages the pursuit of rewards, by transmitting signals within the brain to communicate the pleasurable and exciting nature of those rewards
–> similar to Cloninger’s Novelty Seeking
Reinforcement Sensitivity Theory - Gray
Behavioral Inhibition System (BIS)
= regions of the brain that are responsible for receiving signals from the nervous system which indicate that punishments are being experienced (or may soon be experienced)
–> “stop” system - encourages the avoidance of punishments, by transmitting signals within the brain to communicate the painful and frightening nature of those punishments
–> similar to Cloninger’s Harm Avoidance
Reinforcement Sensitivity Theory - Gray
Fight-or-Flight System
= regions of the brain that are responsible for motivating extreme reactions - fighting and/or fleeing - in response to extremely threatening situations
Theory of Personality - Eysenck
Extraversion
= strength of people’s reactions to stimulation of their senses –> arousability of their brains
–> very extraverted people tend to seek stimulation, and therefore enjoy bright colors, loud noises, other sensations, and meeting and interacting with lots of people
–> very introverted people tend to avoid stimulation, quieter surroundings, and prefer to be alone or with a few others
Ascending reticular activation system (ARAS):
- a filter that regulates the amount of stimulation that is admitted to the brain from the nervous system, which receives stimulation from the environment
- little stimulation: under-aroused, stimulation-seeking, extraverted personality
- great stimulation: over aroused, stimulation-avoiding, introverted personality
–> related to Gray’s Behavioral Activation System
Theory of Personality - Eysenck
Neuroticism
= the strength of people’s reactions to stressful stimuli
–> very neurotic people feel a great deal of worry and nervousness in response to life’s problems
–> emotionally stable people feel little of the negative emotions that are caused by life’s distresses
Limbic System:
- regulate responses to stress
- overwhelmed by stressors: neurotic personality
- handle stressors: stable personality
–> related to Gray’s Behavioral Inhibition System
Theory of Personality - Eysenck
Psychoticism
= traits such as aggressiveness, manipulation, tough-mindedness, risk-taking, irresponsibility, and impulsivity versus their opposites
–> high levels of Psychoticism were associated with criminal behavior, various mental illnesses, and creativity
–> persons high in Psychoticism tended to have high levels of the hormone testosterone and low levels of monoamine oxidase (MOA)
Zuckerman’s Model
Five factors are believed to represent the basic dimensions of personality/temperament:
Activity
Sociability
Impulsive Sensation-Seeking
Aggression
Neuroticism- Anxiety
–> each of the personality dimensions is caused by its own set of complex interactions among brain structures, neurotransmitters, and hormones, and not by a single one of these
Testosterone
= a hormone that is responsible for many of the physical characteristics of men
–> testosterone levels can be influenced by events: competitive situations; increase after victory
–> higher levels of testosterone: wilder, more unruly, more rambunctious, more violent crimes
–> women do naturally have some testosterone, but men’s levels are typically at least 10 x higher
–> triggers the development of male reproductive sex organs and male secondary sex organs
