Neuroscience Exam 4

Experiences that change the brain

development, culture, preferences, coping

Neuroplasticity

the nervous system's potential for physical or chemical change that enhances its adaptability

Learning

a change in an organism's behavior as a result of experience

Memory

the ability to recall or recognize previous experince

Memory Trace

a mental representation of a previous experience

Memory Trace presumed to

correspond to some physical change in the brain

Pavlovian Conditioning

learning procedure whereby a neutral stimulus comes to elicit a response because of its repeated pairing with some relevant event

Pavlovian Conditioning is also called

classical conditioning

Unconditioned Stimulus

a stimulus that unconditionally - naturally and automatically triggers a response

Unconditioned Stimulus Example

food

Conditioned Stimulus

an originally neutral stimulus that, after association with an unconditioned stimulus, triggers a conditioned response

Conditioned and Unconditioned Stimulus can be

the same

Unconditioned Response

the unlearned naturally occurring response to the unconditioned stimulus

Unconditioned Response Example

salivation when food is in the mouth

Conditioned Response

the learned response to a formerly neutral conditioned stimulus

Conditioned Response Example

salivation to the bell

Operant Conditioning

learning procedure in which consequences of a particular behavior increase or decrease the probability of the behavior occurring again

Operant conditioning is also called

instrumental conditioning

Operant Conditioning Example

An animal rewarded for performing a certain behavior

Explicit Memory is \_______ memory

conscious memory

Explicit Memory

memory of facts and experiences that one can consciously know and "declare"

Explicit Memory Example

remembering a specific driving lesson

Conscious Memory

subjects can retrieve an item and indicate that they know that the retrieved item is the correct item

Implicit Memory is \_____ memory

unconscious memory

Implicit Memory

retention independent of conscious recollection

Implicit Memory Example

riding a bike

Unconscious Memory

subjects can demonstrate knowledge, such as a skill, conditioned response, or recalling events on prompting, but cannot explicitly retrieve the information

Declarative Memory

ability to recount what one knows, to detail the time, place, and circumstances of events

What type of memory is lost in amnesia

declarative memory

Procedural Memory

ability to recall a movement sequence or how to perform some act or behavior

Mirror Drawing Task

procedural memory (task can differentiate between performance and memory of rules of the task)

Bilateral Medial Temporal Lobe Resection Causes what affects

no explicit memory

In Bilateral Medial Temporal Lobe this type of memory was left intact

implicit memory

Hippocampus consolidates

new memories

In consolidation, or stabilizing a memory trace after learning, memories move from the \__________ to diffuse regions in the \_______

hippocampus, neocortex

Once memories are moved, \_________ involvement is no longer needed

hippocampal

Visuospatial Memory

using visual information to identify an object's location in space

Beings with selective hippocampal injury have severe deficits in

various forms of spatial memory

Monkeys with hippocampal lesions have difficulty learning the

location of objects

Object Position Task

displace the object that is in the same position as it was in the initial presentation

Animals with good spatial memories should have bigger \______ than do species with poorer spatial memories

hippocampi

Long Term Memory (indefinite duration) involves

the temporal lobe

Short Term Memory (few minutes in duration) involves

the frontal lobe

There is no single place in the nervous system that can be identified as the location of

memory or learning

All sensory systems project to the

frontal lobes

Episodic Memory

autobiographical memory for events linked to specific place and time contexts

Episodic Memory Example

remembering your first day of school

Episodic Amnesia

inability to recall any personally experienced events

Episodic Amnesia is associated with

frontal lobe injuries or reduced blood flow to the frontal lobe

\______ lobes may allow us to mentally travel through our past

frontal

Emotional Memory

memory for the affective properties of stimuli or events

Emotional Memory could be

implicit or explicit

\______ is critical for emotional memory

amygdala

Damage to amygdala abolishes \_______ memory, but has little effect on \_______ or \_____ memory

emotional, implicit or explicit

Explicit Memory contains

episodic, personal, autobiographical, semantic, facts, and knowledge (conscious)

Implicit Memory contains

skills, habits, priming, conditioning (unconscious)

Emotional Memory contains

attraction, avoidance, fear, also both implicit and explicit (conscious and unconscious)

Encoding Memories in explicit tasks the person has an

active encoding role

Encoding Memories in implicit tasks the person has an

passive encoding role

Explicit information is processed in a …. manner

top down or conceptually driven manner

Implicit information is processed in a …. manner

bottom up or data driven

Top down/conceptually driven manner

the subject reorganizes the information before it is encoded

Bottom up or data driven manner

information is encoded in the same way it was perceived

Reciprocal Circuitry for Explicit Memory

cortical structures involved in memory

Unidirectional Circuitry for Implicit Memory

cortical structures involved in memory + substantia nigra → basal ganglia → thalamus → premotor cortex

The unidirectional flow of information may account for the unconscious nature of

implicit memories

At the neural level, memory is associated with changes that take place at the

synapse

Long term Potentiation

in response to stimulation at a synapse changed amplitude of an excitatory postsynaptic potential that lasts for hours to days or longer

Long term potentiation plays a part in

associative learning

In long term potentiation for the EPSP to increase in size more neurotransmitter must be released from the

presynaptic membrane

In long term potentiation for the EPSP to increase in size postsynaptic membrane must become ___ ____ to the same amount of transmitter

more sensitive

In neural processes the strong stimulation alters

postsynaptic receptor sensitivity

A change in postsynaptic receptor sensitivity allows Ca 2+to enter the postsynaptic neuron and

activate a second messenger

In modifying existing circuits a second messenger alters the gene expression in nucleus which changes the synapse by

increasing the function of receptors, formation of new synapses, and structural changes in the synapse

Neurons change their structure in response to their

changing expereincesc

Changes in the number of dendrites can be used to

infer synaptic changesN

New synapses can form between neurons that are already connected or

between neurons that were not previously connected

Long Term Depression is a decrease in

EPSP size

Long Term Depression is another form of

synaptic plasticity

Long Term Depression a neuron becomes less active in response to

repeated stimulation

High levels of estrogen lead to

more dendritic spines in the hippocampus

Low levels of estrogen lead to

more dendritic spines in cortex but fewer dendritic spines in the hippocampus L

Low levels of testosterone leads to

more dendritic spines in cortex

Glucocorticoids are released from the

adrenal glands in times of stress

Glucocorticoids assist in the metabolism of … and …. and the …..

proteins, carbohydrates, control of sugar levels in the blood and cells

Steady levels of glucocorticoids that are seen with prolonged stress may be

neurotoxic

Behavioral Sensitization

the process whereby repeated, intermittent stimulant administration produces a progressively greater and enduring behavioral response.

Drug Induced behavioral sensitization

escalating behavioral response to the repeated administration of a psychomotor stimulant

Sensitization is associated with an increased number of

receptors, synapses, and dendrites

Changes in behavioral sensitization are localized to regions that receive

a large dopamine projection

Possible ways to recover from brain injury

learn new ways to solve problems (behavioral level), reorganize the brain to do with less (structure/circuit level), generate new neurons to produce new circuits (cell/circuit level)

In response to injury the brain can

form new connections and “do more with less”

The amount of recovery is increased significantly if the person also

engages in some form of intervention: behavioral or pharmacological therapy

Stem Cell Implantation has had … success to date; more suited for ….

limited, situations where only a small number of cells are needed

Behavioral change reflects

change in the brain

All nervous systems are

plastic in the same general way

Plastic changes are

age specific

Prenatal events can

influence brain plasticity throughout life

Plastic changes are

brain region dependent

Experience dependent changes

interact (metaplasticity)