Motivation and Emotion unit 4

biological basis of motivation

functions of the brain? 3 pts

1. cognitive and intellectual functions- thinking brain

2. motivational functions- motivated brain

3. emotional functions- emotional brain

what are the principles for studying the motivated brain?

environmental event → biochemical → brain structure → motivation

brain structures involved in the BAS (behavioral activation system) ? 5 pts

1. reticular formation

2. hypothalamus

3. medial forebrain bundle

4. orbitofrontal cortex

5. left prefrontal cortex

brain structures involved in the BIS (behavioral inhibition system)? 3 pts

1. amygdala

2. hippocampus

3. right prefrontal cortex

what is the BAS? 2 pts

1. depends on the dopaminergic circuits 2.g. tegmental area, ventral striatum, prefrontal cortex projections

2. higher levelsl of BAS activity are associated with a higher level of impulsivity and more addictive behaviors

what is BIS? 2 pts

1. depends on the septohippocampal system which interacts with brainstem serotonin signals, the amygdala, and the prefrontal cortex

2. highly sensitized and reactive to approach/avoidance conflict leading to anxiety and inhibition of behavior

approach-oriented structures: hypothalamus

1. regulates important basec motives e.g. hunger, thirst

2. part of the diencephalon

3. make up less than 1% of the total brain volume despite being a motivational giant

4. comprises of a collection of 20 interconnected nuclei

5. controls the hypophysis and the ANS

approach-oriented structures: medial forebrain bundle

1. consists of the hypothalamus, ventral tegmental area, mamillary bodies, septal area, etc

2. stimulation here creates pleasure and leads animals to act as though they have just received positive reinforcement

3. generates positive emotions in humans that boost motivated behavior

approach-oriented structures: orbitofrontal cortex

processes inventive-related information that helps people make choices between options

approach-oriented structures: ventral tegmental area

1. located in the midbrain

2. main source of dopamine neurons that project to limbic and cortical regions

3. releases dopamine when we encounter rewards, goals or incentives

approach-oriented structures: ventral striatum

1. central structure for reward, anticipation, reinforcement learning and desire

2. drives the energizing feeling associated with goal pursuit

3. translates reward signals into action tendancies

approach-oriented structures: left prefrontal cortex

1. associated with approach motivation and positive effect

2. active when planning to pursue goals or rewards

3. supports goal-directed action, persistence, and optimism

4. higher activity leads to higher BAS activation

approach-oriented structures: (basolateral) amygdala

1. evaluates emotional significance of positive cues

2. attaches incentice salience

3. amplifies reward-seeking e.g. “this looks good”

4. tags rewarding stimuli with emotional value that motivates pursuit

avoidance-oriented structures: amygdala

1. interconnected nuclei associated with emotion and motivation

2. sends projections to almost all parts of the brain but receives only a few projections back

3. aids in the perception of others emotions and emotional generation especially in self-defense

4. found in the temporal lobe close to the hippocampus

5. detects threats, punishment cues, and fear-related stimuli

6. communicates with the hippocampus to encode fear memories

7. warns the prefrontal cortex of danger

avoidance-oriented structures: septohippocampal system

involves several intergrates structures:

1. nucleus accumbent- plays a critical role in the experience of pleasure from naturally occuring reinforcers e.g. good food

2. anterior cingulate cortex- controls day to day mood, volition and decision making

3. hippocampus- acts as a warning system that detects novelty, uncertainty, or conflict and makes comparisons of current events with expectations to generate anxious cautions when needed

4. septal area- regulates hippocampal theta rhythms for risks assessment and decision

avoidance-oriented structures: right prefrontal cortex

1. associated with withdrawal behavior, negative affect, and behavioral inhibition

2. active during worry, caution, and conflict monitoring

3. evaluates potential losses/punishment

arousal and activation structures: reticular formation

1. made up of a network of interconnected nuclei running through the brainstem and intergrates sensory, autonomic, motor, and emotional information

2. controls the transition between sleep, wakefulness, and attention

3. sends activating signals to the thalamus, hypothalamus, basal forebrain, and cerebral cortext to increase the brain’s activation, alertness, and readiness to act

4. sets the overall arousal level for all brain activity

5. prepares the body for approach actions

arousal and activation structures: prefrontal cortex

1. covers the front part of the frontal lobe and is associated with planning, cognitive behavior, personality expression, decision making, and moderating social behavior e.g. controlling anger

2. the medial prefrontal cortex/prelimbic core plays a central role in the learning of response-outcome contingencies that underlie perceptions of control and mastery motivation

3. learning the response-outcome contingencies greatly contributes to goal-desired outcome-seeking action

4. the left prefrontal cortex is associated with approach-oriented/positive feelings

5. the right prefrontal cortex is associated with avoidance oriented/negative feelings

what are the individual differences in prefrontal activation? 3 pts

1. sensitive left prefrontal lobe- vulnerable to positive emotions and incentives and experiences of positive emotions that can lead to addictions

2. sensitive right prefrontal lobe- vulnerable to negative emotions e.g. in anxiety disorders

3. some disorders such as ADHD can cause stagnation in the anatomical growth of their prefrontal cortex meaning they never reach full maturity

what are neurotransmitters? 1 pt

chemical messengers responsible for transmitting signals across a chemical synapse and are released from synaptic vesicles in synapses into the synpatic cleft where they are received by receptors on target cells

can be inhibitory or excitatory

what are the 4 motivationally relevant neurotransmitter pathways? 4 pts

1. dopamine- good feelings/rewards

2. serotonin- mood and emotions

3. norepinephrine- arousal and alertness

4. endorphin- inhibits pain and anxiety

dopamine release and incentives

1. incentives and the anticipation of a reward triggers dopamine release in the brain resulting in pleasure

2. participates in the preparatory phase of motivated behavior

dopamine release and rewards

1. teaches us which events are rewarding and explains the experience of reinforcement

2. unpredicted rewarding events are associated with greater dopamine release

dopamine release and motivation

1. associated with positive feelings and voluntary goal-directed approach responses

2. includes the nucleus accumbens which is involved in the release of locomotion in goal directed behavior

3. stimulation of areas in the midbrain and nucleus accumbens activates exploration as dopamine is associated with exploration behaviors towards specific goals

dopamine and addiction

1. repeated usage of addictive drugs creates hypersensitivity to dopamine stimulation in the nucleus accumbens that can last years

2. psychostimulants are potent reinforcers

functions of cortisol? 3 pts

PATHWAY: hypothalamic-pituitary-adrenocortical system

1. prepares the body to deal with stress by releasing glucose, heightening vigilance, focusing attention on threats, and suppressing non-essential functioning e.g. reproduction

2. heightened levels are associated with poor health and intellectual reasoning

functions of testosterone? 3 pts

1. associated with high sexual motivation, same-sex competitions. and mate-seeking behaviors

2. increases approach motivation, confidence, assertiveness, and persistence in challenging/competitive tasks while reducing a fear of punishment

3. increases status-seeking behavior and can promote aggressive behavior or prosocial behavior to accomplish goals

functions of oxytocin? 4 pts

1. bonding hormones related to trust, caregiving, and emotional closeness

2. reduces stress-responses and cortisol levels

3. enhances the feeling of safety with others and encourages support seeking

4. is released during physical touch, romantic intimacy, bonding moments etc