Personality Prelim 2

What are the important functions of the “social” brain?

1. Evaluation of rewards and threats, which occurs continuously, automatically, and often nonconsciously

2. Executive control, which regulates behavior according to longer-term and more abstract goals; allows for the intentional inhibition of actions that are incompatible with goals

[social brain] evaluation

rapidly detecting potential rewards and threats in the environment to promote quick action

[social brain] executive control

allows people to intentionally regulate thoughts and behaviors and inhibit actions that conflict with goals

How do neural systems relate to behavior?

Behavior arises from the synchronization of neural activity across brain regions, not from a single brain area acting alone; functions emerge from neural networks

Brain regions are multifunctional (e.g. amygdala), although some regions are more strongly implicated with particular functions

What are the 3 major neural systems relevant to personality?

1. Reward/Approach (BAS)

2. Threat/Avoidance (BIS)

3. Executive Control

temperament

characteristic ways of responding to the world that are present early in life and from which adult personality develops; it is assumed to largely reflect inherited biological tendencies

How is temperament different from personality?

Temperament: rooted in inherited biology, appears early in life, and reflects how a person typically responds (activity level, mood, emotional reactivity); NOT affected by experience

Personality: modified through maturation and experience and includes beliefs, values, goals, and personal narratives; includes the what and why of response

How was Rothbart & Derryberry's model of temperament developed?

using psychobiological approaches that linked temperament dimensions to underlying neural networks and biological functioning

by combining brain science, genetics, and psychology to explain why children act differently from birth.

Instead of just looking at a child's behavior, they built a framework based on how the body and mind interact through two main systems:

• Reactivity: How quickly and strongly a child's body and emotions react to things around them (like a loud noise or a new toy).

• Self-Regulation: How the child uses their brain and body—especially attention and focus—to calm down or manage that reaction.

By linking these two systems, they shifted the study of temperament away from just "behavior habits" and redefined it as a biological, brain-based system that evolves as a child grows

How was Rothbart and Derryberry’s Model developed differently from the Big Five?

• Rothbart and Derryberry: temperament model was developed from developmental and psychobiological research on children and infants

• Big Five: developed primarily through the lexical/factor-analytic approach by examining trait-descriptive language and adult personality ratings

How are Rothbart and Derryberry’s dimensions of temperament assessed, and how is it different from assessing adult personality?

• Temperament is often assessed through caregiver reports, behavioral observations, and laboratory tasks in infants and children

• Adult personality is typically assessed using self-report personality inventories (e.g., Big Five measures)

What are the 3 dimensions of Rothbart & Derryberry's temperament model?

Extraversion, Negative Affectivity, and Effortful Control

[R&D temperament model] reactivity

the arousability of physiological and behavioral systems

• stimulus intensity, including novelty

• response latency, intensity, and recovery following stimulation

[temperament] extraversion

dimension reflecting positive affect, approach tendencies, activity, impulsivity, anticipation of reward, and responsiveness to novelty and challenge

[temperament] behaviors associated with extraversion

high activity, social approach, low behavioral inhibition (novelty/challenge), impulsive (quick) responding, smiling, laughter, and excitement about anticipated rewards

[temperament] negative affectivity

dimension reflecting proneness to frustration, fear, discomfort, sadness, and other negative emotional responses

[temperament] behaviors associated with negative affectivity

frustration after goal blockage or interruption of ongoing tasks, fear of anticipated distress, discomfort with stimulation or complexity, sadness due to loss/suffering/disappointment

[temperament] effortful control

self-regulatory dimension involving attentional control, inhibitory control, perceptual sensitivity, and the ability to regulate behavior deliberately

[temperament] behaviors associated with effortful control

focusing attention, shifting attention when needed, suppressing inappropriate responses, detecting subtle environmental changes, enjoying lower-intensity stimuli

How does temperament relate to adult personality? Is temperament destiny?

Extraversion temperament predicts adult Extraversion. Childhood Extraversion predicts impulsiveness and externalizing behavior. Effortful Control predicts adult Conscientiousness.

Temperament shows some stability, but it is influenced by maturation and experience over time. It is not destiny.

What are the 2 goals of personality neuroscience?

1. Identify brain circuits/networks associated with socially relevant processes

2. Understand how individual differences in brain circuitry relate to differences in individual behavior

behavioral activation system (BAS)

reward/approach system that is sensitive to rewards and promotes approach behavior; it generates positive affect and motivation to pursue desired outcomes

What triggers BAS activation?

rewards such as food, touch, money, and good grades

What behaviors does BAS govern?

appetitive behavior, approach motivation, pursuit of rewards, and goal-directed action ("GO!")

What neural circuitry is associated with BAS?

dopaminergic pathways involving the Ventral Tegmental Area (VTA) and Nucleus Accumbens (NA)

What is dopamine's role in reward processing?

contributes to reward learning, anticipation, motivation, and pursuit of rewards ("wanting")

What feeling states are associated with reward-system activation?

positive affect, approach motivation, anticipation, pursuit of desired outcomes

behavioral inhibition system (BIS)

threat/avoidance system that responds to potential punishment, threat, novelty, or nonreward and promotes avoidance behavior

What triggers BIS activation?

physical pain, discomfort, loss of money, poor grades, novelty, punishment, nonreward

What behaviors does BIS govern?

avoidance behavior, heightened alertness, physiological arousal, inhibition of ongoing behavior ("STOP!")

What neural circuitry is associated with BIS?

amygdala and anterior cingulate cortex (ACC)/threat & conflict monitoring systems

What are the functions of the amygdala?

responds to negative fear-eliciting stimuli, positive approach-related stimuli, and helps compute the degree to which a stimulus may be a threat or a reward

executive functions

cognitive processes that support goal-directed behavior and inhibit inappropriate or goal-irrelevant responses; also called cognitive control, self-control, or inhibitory control

What neural region is most strongly associated with executive function?

prefrontal cortex (PFC)

[executive control] attentional control

the ability to selectively focus on one aspect of a situation while ignoring others

[executive control] representational control

the ability to maintain goal-relevant mental representations and resolve interference among competing thoughts in memory

[executive control] impulse/behavioral control

the ability to inhibit task-irrelevant behaviors and impulses

Stroop task

task in which participants must name the ink color of a stimulus while ignoring the written word

• Congruent trial: the word meaning and ink color match (e.g., the word "RED" printed in red ink)

• Incongruent trial: the word meaning and ink color conflict (e.g., the word "RED" printed in blue ink)

• Key dependent variable: reaction time and/or accuracy when naming the ink color

How does the Stroop task relate to executive control?

measures behavioral/impulse control + attentional control and interference resolution; requires participants to inhibit the habitual response of reading the word and instead provide the less automatic response of naming the ink color

What is the effect of stress on executive control?

Impairment: under high stress, individuals rely more on quick, dominant, well-learned responses; under low stress, they can accumulate information and engage in less dominant, more controlled responses

neuroscience view of personality

personality reflects the functioning of neural circuitry involved in evaluating opportunities and threats and regulating behavior in pursuit of long-term goals

Yerkes-Dodson law

• Performance is highest at moderate levels of arousal

• Very low arousal may lead to poor engagement

• Very high arousal/stress impairs performance, especially on complex tasks requiring executive control

hypothalamus

connected to everything else in the brain and plays a central role in fundamental behaviors such as fighting, fleeing, feeding, and mating; triggers the secretion of several hormones

amygdala

has a central role in emotion, including learning what objects to fear

nucleus accumbens

implicated in responsiveness to reward

anterior cingulate

hormones

biological substances that affect the body in locations different from where they were produced

neurotransmitters

critical for communication across the synapses between neurons

neocortex

outer layer of the cortex of the brain, regarded as uniquely human; handles higher-order brain functions, including sensory perception, conscious thought, spatial reasoning, language, and motor command generation

dopamine

serotonin

testosterone

cortisol

oxytocin

synapse

the space between two neurons across which impulses are carried by neurotransmitters

neuron

a cell of the nervous system that receives and transmits information; also called nerve cell

lessons of psychosurgery involving the role of lobotomies

EEG

MEG

PET

fMRI

TMS