BRAIN, MIND, BEHAVIOR- HEYMAN- EXAM 2

What are the 3 time scales of Brain Plasticity?

Evolutionary time (review of the remarkable changes over a relatively short period of time)

Developmental changes (within a lifetime)

Experiential changes (moment to moment)

What kind of genes contribute to larger brain size for humans?

Genes that play a role in generating neurons, and our Notch2NL genes

What are Notch2NL genes?

They help create cells that later become neurons, and the tissue triples in size when combined with isolated brain tissue

What are the 5 differences between non-human primates and humans?

- Absolute and relative brain size

- Changes in shape (prefrontal cortex and cerebellum)

- Our neurons have more dendrites and longer axons

- "Novel" structures in the parietal region of the brain involved in complicated thinking and movement.

- Genes that increase number of neurons in brain tissue and slow brain development

What are some theories that environmental pressures favor brains with more neuronal interconnections?

1. Climate change = drier landscape and primates came down from trees, started walking upright and vision became more important

2. tools and hunting, which required more brain power and planning, etc.

3. Cooking-- required more brain power, and also increased calories/energy for neurons

What is gray matter?

areas of the nervous system with a high densityof cell bodies and dendrites, few myelinated axons, e.g.cortex

What is white matter?

areas of the nervous system containing mostly myelinated axons (e.g., corpus callosum)

What does white matter do?

carry signals from one part of the CNS to another

what does grey matter do?

Processes and regulates information in the CNS

What did the longitudinal MRI study on white matter show?

measured the density of white matter in the brain, showed that percent of white matter in brain increases with age

What did the morphometric study of human cerebral cortex development on gray matter show?

- a study of density of gray matter at different ages.

- focused on visual cortex

The developmental trajectory of changes in gray matter will:

will increase to about age 1 then steadily decrease

Assume different brain regions have different gray matter density trajectories. How should they be ordered?

What improves as gray matter decreases?

Cognitive function improves because unused connections are pruned away, and the remaining connections get more use/get stronger

Increase in density of white matter continues into...

3rd decade of life

post-natal white matter/grey matter development age range:

initial increase and then a decrease

when do the sensory areas (occipital lope) change?

early on

when do the prefrontal cortex and decision making change?

later on

Which idea is consistent with the idea that experience plays a role in gray matter pruning:

the blindfolded kitten experiment

What increases risk for schizophrenia?

too much pruning

What increases risk for autism?

Too little pruning

What does the London taxi cab experiment show?

The percentage of grey matter in the hippocampus grow and the size of the hippocampus grows

what is classical conditioning?

learning associations and generalization of reflexes to new stimuli

what is Operant/Reward based learning?

How consequences (rewards/punishment) shape behavior

Who was pavlov?

Nobel prize winning physiologist established procedures for studying digestion in living animals.

What is Pavlov's experiment?

He was interested in the way behavior is conditioned by a stimulus. Therefore, he conducted an experiment where he made a dog salivate to the sound of the bell rather than food.

US =

UR =

CS =

CR =

unconditioned stimulus

unconditioned response

conditioned stimulus

conditioned response

What are the classical conditioning basics as understood by Pavlov:

The CR is very much like the UR

But as a function of experience it is triggered by the CS that was paired with the US

This can be adaptive (but not necessarily)

why has classical conditioning attracted interest?

A simple but powerful way to adapt to a complex world, highly general across species

What are the necessary & sufficient conditions for learning?

- Pairings

- backwards conditioning doesn't work

what's the relationship between pairings and conditioned responses?

The more often the pairing occurs, the stronger the conditioned response

Early pairings have more effect than later pairings

Why do we obey the law?

(1) The feelings of guilt and virtue motivate us to obey the law and resist temptation

2) establishing emotional responses to new stimuli

The necessary and sufficient conditions to establish classical conditioning (learned associations):

Role of expectations

what are phobias?

irrational fear of a specific object or situation

what percent of the population is impacted by phobias?

2-8% population

what's the Little Hans case?

Hans was a five-year-old who developed a phobia of horses after seeing one fall down and die.

Freudian Interpretation of phobias

people have unconscious impulses or thoughts that cause conflict between the three parts of the human personality or psyche: the id, superego, and ego.

Can we find everyday (outside of the lab) evidence of role of conditioning in phobias?

Yes, the defibrillator study.... 72 patients with implantable cardio/defibrillators, many patients can anticipate arrhythmias thus anticipate shock.... 16% developed anxiety disorders, including phobias, over a 6 year period

According to CC, how do you extinguish a conditioned response?

Present the CS without the US

Arachnophobia experiment:

from pictures of spiders to handling a real spider in a group setting (exposure, "extinction" & relaxation )

Stimulus hierarchy

Teach relaxation (that competes with fear)

Observations that do not fit classical conditioning account of phobias

traumatic events typically do not result in phobias

Phobias but no known trauma

Some stimuli are much more likely to be the focus of phobias than others

Anxiety disorders: Heritability studies

11% if no disorders in parents,

25% if one parent suffers from anxiety, and

40% of both parents suffer from anxiety.

Monkey Snake experiment

many lab-reared monkeys are not ostensibly afraid of snakes; wild reared monkeys are always very afraid.... when scared monkeys, watched brave monkeys, they became less afraid

How to explain what does not fit CC account?

- Imitation learning

- Inference

- Genetic differences in susceptibility to stressors

how to explain success of classical conditioning based treatment and apparent causal discrepancies

inference and imitation (observation/empathy) trigger internal conditioning trials

How to "face your fears"?

Treatments based on conditioning are effective and produce biological as well as behavioral changes.

Hang out with good role models (e.g., "brave monkeys")

What did Pavlov achieve

revealed that conditioned behavior was highly orderly: Strength of conditioning varied systematically as function of UCS properties, CS properties, and timing of presentation of stimuli

Who was Skinner?

behaviorist who developed the origins of voluntary behavior (shaping) and

it's persistence and pattern (schedules of reinforcement)

What is operant conditioning?

the learning of voluntary behavior through the effects of pleasant and unpleasant consequences to responses

What was the origin of reinforced behavior?

- Spontaneous actions

- Shaping

- This is reminiscent of Darwin

what is shaping in operant conditioning?

rewards and punishments select certain actions, thereby producing new topographies

Why does persistence, frequency and timing of reinforced behavior matter?

History of reinforcement ("schedules of reinforcement") determines topography of voluntary actions, when they occur, and their frequency

discriminative stimulus

an event that sets the occasion for a reinforcement contingency to be in effect

Operant Behavior

any pattern of behavior that yields a particular reinforcer. An operant is a means to an end, rather than a specific response.

Reinforcer

Any event that increases the frequency of preceding activities

Schedule of reinforcement (contingency of reinforcement):

A rule that specifies the relationship between voluntary action and its consequences (like a contract):

Examples of schedules of reinforcement

- every 10 lever presses yields a reward

- after a delay of 30 seconds from the last reward, the next response will produce a reward.

How to measure patterns of behavior

- the "cumulative recorder"

Why is there a pause in responding after a reward on fixed ratio and fixed interval schedules?

different histories of reinforcement (schedules) should yield

different cumulative recorder patterns...

Notice that the reinforcer in operant conditioning can be the same as the US in classical conditioning. Is it also true that ?

In operant conditioning the subject's behavior determines whether the reward (US) is delivered

What are some reinforcement that applies to gymnasts?

what their coaches think, or social reinforcers

the dictator game

A mutually anonymous behavioral economics game in which one person ("the dictator") unilaterally determines how to split an amount of money with the second player.

in operant conditioning new behaviors emerge as __________________________ and ------------------------

the result of more or less random movements;

an environment or experimenter that rewards a subset of the randomvariations

In the article titled: "What happens when contingency treatment ends?" The intervention involved ___________. The basic finding was

a chance to win prizes; neither client resumed regular drug use

The logic of reinforced learning is the same as the logic of

natural selection

compulsion

an irresistible urge to behave in a way that is incompatible with one's conscious wishes

Why is self-control important?

self control predicts good health, higher income, and better school performance.

What's the rule regarding time and rewards

you always choose the reward with highest value

skinner argues that _____ of behavior are based on ________

conventional explanations; internal states

__________ are also a function of their history of reinforcement

internal events

psychology should focus on.....

tangible histories of reinforcement and patterns of overt behavior