Set #6 (Lecture 22 + Textbook PGs 224-228 Study Guide)

What is motivation?

The drive to engage in behaviors, such as eating, drinking, sleeping, working, or seeking rewarding experiences.

What is the difference between internal and external motivational cues?

Internal cues come from changes within the body, such as dehydration or decreased blood pressure. External cues come from the environment, such as seeing food.

How does homeostasis influence motivation?

The body detects internal changes and motivates behaviors that restore conditions to their optimal set points.

What three homeostatic behaviors were used as examples of internally motivated behavior?

Eating, drinking, and thermoregulation.

How can sensory information from the environment influence motivation?

The brain evaluates external stimuli and uses previous experiences to help determine which behaviors to approach or avoid.

What is pleasure?

The immediate positive feeling experienced while doing something enjoyable.

What is reward?

An experience involving pleasure, motivation, anticipation, and learning from previous outcomes.

What is subjective well-being?

A person's individual experience of pleasure, reward, and happiness.

What does work mean when studying motivation?

The physical or mental effort used to obtain something desirable.

What was the purpose of White and Dolan's (2009) study?

To investigate how pleasurable and rewarding people considered different everyday activities.

How did White and Dolan conduct their study?

They asked university students in Germany to report their feelings about various activities.

How did White and Dolan's participants evaluate eating, resting, and watching television?

They considered these activities pleasurable but not particularly rewarding.

How did White and Dolan's participants evaluate working?

They considered working rewarding but not particularly pleasurable.

How did White and Dolan's participants evaluate grooming and self-care?

They considered these activities neither particularly pleasurable nor rewarding.

How did White and Dolan's participants evaluate prayer and meditation?

They considered these activities both pleasurable and rewarding.

What was the main conclusion of White and Dolan's study?

Pleasure and reward are different. An activity can be enjoyable without being especially rewarding, or rewarding without being especially enjoyable.

How did full-time college students spend their time according to the 2013 Bureau of Labor Statistics report?

Approximately 8.7 hours sleeping, 4.1 in leisure and sports, 3.3 in education, 2.4 working, 1 eating and drinking, nearly 1 grooming, 1.5 traveling, and 2 in miscellaneous activities daily.

What is a time budget?

A measure of how people distribute their time among different activities.

Why does spending more time on an activity not necessarily mean it is pleasurable?

People may spend time on activities because they are necessary or rewarding, even when they are not particularly enjoyable.

How do researchers investigate motivation in animals?

They measure observable behaviors, such as how much time or effort an animal spends obtaining a reward.

How can researchers measure maternal motivation in rats?

By measuring how much time a mother rat spends with her pups or how much effort she makes to reach them.

Why do researchers compare animal behavior with human research?

To better understand the brain mechanisms involved in motivation and reward.

What is the amygdala?

A complex group of brain nuclei involved in processing sensory information and influencing behavioral, autonomic, and hormonal responses.

Where is the amygdala located?

Deep within the temporal lobe, near its lower inner portion, with one amygdala on each side of the brain.

Why was the amygdala given its name?

Because its shape was thought to resemble an almond.

Approximately how many nuclei are associated with the amygdala?

22 nuclei.

What are the two major functional divisions of the amygdala?

The basolateral area and the centromedial area.

What is the basolateral amygdala?

The lower and outer region of the amygdala that receives sensory information from several cortical areas.

Which sensory cortical regions send information to the basolateral amygdala?

The visual, auditory, somatosensory, and olfactory cortices.

How does most sensory information reach the cerebral cortex?

It passes through the thalamus, which helps organize and relay sensory information to cortical regions.

What is the major exception to the usual thalamic sensory pathway?

Olfactory information can travel directly to the olfactory cortex without first passing through the thalamus.

What is the centromedial amygdala?

The central and medial region of the amygdala that helps regulate autonomic and hormonal responses.

What are the two major output systems of the amygdala?

A behavioral response system and an autonomic/hormonal response system.

Which structures are involved in the amygdala's behavioral output pathway?

The ventral striatum and dorsomedial thalamus.

Which structures receive output from the centromedial amygdala?

The hypothalamus, midbrain, pons, medulla, and basal forebrain.

What is the difference between behavioral and autonomic responses?

Behavioral responses involve actions, while autonomic responses involve automatic bodily processes, such as gland activity and hormonal changes.

How quickly can sensory information reach the amygdala?

Approximately 50 milliseconds after a stimulus is presented.

Why can the amygdala respond to sensory information so quickly?

It rapidly screens information and helps initiate responses before slower, higher-level cortical processing is completed.

Why is rapid processing by the amygdala important?

It allows an organism to make quick decisions about potentially important or threatening environmental stimuli.

What is the approach-and-avoidance principle of motivation?

Organisms tend to approach stimuli associated with positive outcomes and avoid stimuli associated with negative outcomes.

How do previous positive and negative experiences influence behavior?

Positive experiences encourage repeating or approaching a situation, while negative experiences encourage avoiding it.

Why are approach-and-avoidance associations important for learning and memory?

They help organisms remember which environmental situations are beneficial and which should be avoided.

Who conducted the early experiments that helped identify the brain's reward circuitry?

James Olds and Peter Milner in 1954.

What was the original purpose of Olds and Milner's research?

To investigate brain regions involved in arousal and sleep-wake regulation.

Which brain structure did Olds and Milner initially intend to investigate?

The reticular formation, which is involved in arousal and sleep-wake regulation.

What happened when Olds and Milner accidentally stimulated the septal region?

The electrode was placed in the septal region near the nucleus accumbens instead of the intended brain area. Rats repeatedly sought electrical stimulation because it was rewarding.

Where is the septal region in relation to the nucleus accumbens?

The septal region is near the nucleus accumbens, an important structure in reward circuitry.

How did Olds and Milner allow rats to obtain electrical brain stimulation?

They implanted electrodes and later allowed rats to press a lever or button to deliver a mild electrical current to the stimulated brain region.

How frequently did rats seek rewarding electrical stimulation?

Some pressed the lever up to approximately 2,000 times per hour, with repeated stimulation reaching roughly 10,000 presses daily in the described experiments.

How did repeated brain stimulation affect the rats' other behaviors?

Rats pressed the button up to 10,000 times daily, neglected eating, showed little interest in mating, and ignored their pups. The transcript states that they continued drinking.

What did Olds and Milner's experiments demonstrate?

Certain brain regions are involved in reward and motivation, and stimulating them can strongly reinforce behavior.

What is the nucleus accumbens?

A structure in the ventral striatum that helps process reward-related information and guide motivated behavior.

How does the nucleus accumbens contribute to motivation?

It helps connect sensory information and rewarding outcomes with decisions about what behavior to perform.

What is dopamine?

A neurotransmitter involved in motivation, reward prediction, learning, and selecting behaviors.

What is the substantia nigra?

A midbrain region containing dopamine-producing neurons that project to the dorsal striatum and influence behavioral selection.

What is the ventral tegmental area (VTA)?

A midbrain region containing dopamine-producing neurons that project to several brain regions involved in motivation, reward, and cognition.

What is the mesencephalon?

The midbrain, which contains dopamine-producing regions including the substantia nigra and VTA.

What are the three major dopamine pathways involved in motivation and learning?

The mesostriatal, mesocortical, and mesolimbic pathways.

What is the mesostriatal pathway?

A dopamine pathway from the substantia nigra to the dorsal striatum, particularly the caudate and putamen.

What is the mesocortical pathway?

A dopamine pathway from the VTA to cortical regions involved in cognition, planning, and emotional regulation.

What is the mesolimbic pathway?

A dopamine pathway from the VTA to limbic structures, particularly the nucleus accumbens, involved in reward-related motivation.

How are dopamine pathways named?

Their names describe where they originate and where they project, such as the midbrain-to-cortex mesocortical pathway.

What is the dorsal striatum?

A region containing the caudate and putamen that receives dopamine from the substantia nigra and helps select behaviors.

What is the ventral striatum?

A region including the nucleus accumbens that helps process reward-related information and guide motivated behavior.

What is the ventral pallidum?

The ventral portion of the globus pallidus involved in the output circuitry of the ventral striatum.

How does the dorsal striatal system help select behavior?

Dopamine from the substantia nigra influences striatal circuits that communicate through the globus pallidus and thalamus to help determine appropriate actions.

How can the mesocortical pathway influence emotional regulation?

Dopamine projections to cortical regions such as the cingulate gyrus may help regulate emotional states.

How can the mesocortical pathway influence planning and cognition?

Dopamine projections to frontal cortical regions help support cognitive processing and planning.

What is the main role of the mesolimbic pathway?

Helping determine which incoming stimuli are important and which rewarding outcomes should motivate behavior.

Which brain regions provide information to the ventral striatum?

The amygdala, frontal cortex, hippocampus, and olfactory system, among other regions.

How are the dorsal and ventral striatal systems similar?

Both use dopamine-related circuitry to help select behaviors based on incoming information.

How do the dorsal and ventral striatal systems differ?

The dorsal system receives dopamine from the substantia nigra, while the ventral system receives dopamine from the ventral tegmental area (VTA).

Why are dopamine-related striatal systems described as decision-making gatekeepers?

They help evaluate incoming information and influence which behaviors are selected.

What did Wise and Schwartz (1981) investigate?

Whether dopamine receptor activity contributes to motivation to obtain rewards.

What is pimozide?

A dopamine receptor blocker used to investigate dopamine's role in motivation.

What happened when Wise and Schwartz administered pimozide to rats?

Rats became less motivated to respond for food rewards.

Why was the pimozide dose important in Wise and Schwartz's experiment?

It was low enough that rats could still move normally, showing that their reduced effort to get food was due to lower motivation, not movement problems.

What did Wise and Schwartz's findings demonstrate?

Blocking dopamine receptors can reduce motivation to obtain rewards.

Who was Robert Heath?

A psychiatrist who investigated the effects of electrical stimulation of reward-related brain regions in humans during the 1950s.

What happened when Robert Heath stimulated the septal nuclei in human patients?

Patients repeatedly pressed buttons to receive stimulation, and some described intensely pleasurable or orgasmic sensations.

What alternative explanation was proposed for Heath's findings?

The stimulation may have increased sexual desire rather than directly producing pleasure.

What important distinction did Heath's research raise?

Wanting something and experiencing pleasure from it are not necessarily the same process.

Why is anticipating a reward important for motivation?

Recognizing cues that predict rewards allows an organism to act before receiving the reward, increasing its chances of obtaining it.

How can an initially neutral sensory stimulus become associated with reward?

Repeated pairing with a positive outcome teaches the brain that the stimulus predicts something rewarding.

How does the apple-tree example demonstrate reward learning?

An animal initially experiences reward from eating an apple but can learn that the tree predicts the apple, making the tree itself a reward-related cue.

How can reward prediction extend through multiple environmental cues?

An organism can learn that an earlier cue, such as a forest, predicts another cue, such as an apple tree, which predicts the actual reward.

What happens when a light repeatedly predicts a juice reward?

The dopamine response gradually shifts from receiving the juice to seeing the light that predicts it.

What happens when a tone predicts a light that predicts juice?

The dopamine response can shift to the earlier tone because it predicts the sequence leading to the reward.

Why does dopamine activity shift toward reward-predicting cues?

Recognizing earlier cues helps organisms anticipate rewards and perform behaviors that increase the likelihood of obtaining them.

What is associative learning?

Learning that one event or stimulus predicts another event or outcome.

What is the baseline firing rate of dopamine neurons?

Their normal, relatively low firing rate when no unexpected reward is occurring.

What happens to dopamine neurons when an unexpected reward is received?

They produce a sudden burst of firing because the reward was not predicted.

How does dopamine activity change while an animal learns that a light predicts a treat?

Dopamine firing gradually increases in response to the light and decreases in response to receiving the treat.

What happens to dopamine neurons after an animal fully learns that a light predicts a treat?

The light produces a dopamine burst, while receiving the expected treat produces no additional burst.

What happens when an expected reward is not delivered?

Dopamine neuron firing briefly decreases below its normal baseline rate.

What is reward prediction error?

The difference between the reward an organism expected and the reward it actually received.

What is a positive reward prediction error?

An outcome is better than expected, producing a burst of dopamine neuron firing.

What is a zero reward prediction error?

An outcome matches expectations, so receiving the predicted reward produces no additional dopamine burst.

What is a negative reward prediction error?

An outcome is worse than expected, causing dopamine neuron firing to briefly decrease below baseline.

Why is reward prediction error important for learning?

It helps the brain update expectations based on whether actual outcomes are better or worse than predicted.