Transcript PSYC550 Emotions and Memory

PSYC 550
Biological Bases of Behavior
Emotions and Learning
Emotions as Response
Pattern
• medial nucleus
– A group of subuclei of the amygdala that receives sensory input, including
information about the presence of odors and pheromones, and relays it to the
medial basal forebrain and hypothalamus.
• lateral nucleus (LA)
– A nucleus of the amygdala that receives sensory information from the
neocortex, thalamus, and hippocampus and send projections to the basal,
accessory basal, and central nucleus of the amygdala.
• central nucleus (CE)
– The region of the amygdala that receives information from the basal, lateral,
and accessory basal nuclei and sends projections to a wide variety of regions
in the brain; involved in emotional responses.
Emotions as Response
Pattern
• conditioned emotional response
– A classically conditioned response that occurs when a neutral stimulus is
followed by an aversive stimulus; usually includes autonomic, behavioral, and
endocrine components such as changes in heart rate, freezing, and secretion
of stress-related hormones.
• threat behavior
– A stereotypical species-typical behavior that warns another animal that it may
be attacked if it does not flee or show a submissive behavior.
• defensive behavior
– A species-typical behavior by which an animal defends itself against the threat
of another animal.
Emotions as Response
Pattern
• submissive behavior
– A stereotypical behavior show by an animal in response
to threat behavior by another animal; serves to prevent
an attack.
• predation
– Attack of one animal directed at an individual of
another species on which the attacking animal normally
preys.
Emotions as Response
Pattern
• orbitofrontal cortex
– The region of the prefrontal cortex at the base of the
anterior frontal lobes, just above the orbits of the eyes.
• ventromedial prefrontal cortex
– The region of the prefrontal cortex at the base of the
anterior frontal lobes, adjacent to the midline.
Communication of
Emotions
• volitional facial paresis
– Difficulty in moving the facial muscles voluntarily; caused by
damage to the face region of the primary motor cortex or its
subcortical connections.
• emotional facial paresis
– Lack of movement of facial muscles in response to emotions in
people who have no difficulty moving these muscles voluntarily;
caused by damage to the insular prefrontal cortex, subcortical
white matter of the frontal lobe, or parts of the thalamus.
Copyright © Allyn & Bacon 2007
Learning
The Nature of Learning
• perceptual learning
– Learning to recognize a particular stimulus.
• stimulus-response learning
– Learning to automatically make a particular response in
the presence of a particular stimulus; includes classical
and instrumental conditioning.
The Nature of Learning
• classical conditioning
• Hebb rule
– The hypothesis proposed by Donald Hebb that the
cellular basis of learning involves strengthening of a
synapse that is repeatedly active when the postsynaptic
neuron fires.
The Nature of Learning
• instrumental conditioning
– A learning procedure whereby the effects of a particular behavior
in a particular situation increase (reinforce) or decrease (punish)
the probability of the behavior; also called operant conditioning.
• reinforcing stimulus
– An appetitive stimulus that follows a particular behavior and thus
makes the behavior become more frequent.
• punishing stimulus
– An aversive stimulus that follows a particular behavior and thus
makes the behavior become less frequent.
• motor learning
– Learning to make a new response.
Synaptic Plasticity: LongTerm Potentiation and
Long-Term Depression
• long-term potentiation (LTP)
– A long-term increase in the excitability of a neuron to a particular
synaptic input caused by repeated high-frequency activity.
• hippocampal formation
– A forebrain structure of the temporal lobe, constituting an
important part of the limbic system; includes the hippocampus
proper (Ammon’s horn), dentate gyrus, and subiculum.
• entorhinal cortex
– A region of the limbic cortex that provides the major source of
input to the hippocampal formation.
Synaptic Plasticity: Long-Term
Potentiation and Long-Term
Depression
• dentate gyrus
– Part of the hippocampal formation; receives inputs from the entorhinal
cortex and projects to the filed CA3 of the hippocampus.
• perforant path
– The system of axons that travel from cells in the entorhinal cortex to
the dentate gyrus of the hippocampal formation.
• field CA3
– Part of the hippocampus; receives input from the dentate gyrus and
projects to the field CA1.
• pyramidal cell
– A category of large neurons with a pyramid shape; found in the
cerebral cortex and Ammon’s horn of the hippocampal formation.
Synaptic Plasticity: Long-Term
Potentiation and Long-Term
Depression
• field CA1
– Part of the hippocampus; receives inputs from field CA3 and projects
out of the hippocampal formation via the subiculum.
• population EPSP
– An evoked potential that represents the EPSPs of a population of
neurons.
• associative long-term potentiation
– A long-term potentiation in which concurrent stimulation of weak and
strong synapses to a given neuron strengthens the weak ones.
• NMDA receptor
– A specialized ionotropic glutamate receptor that controls a calcium
channel that is normally blocked by Mg2+ ions; involved in long-term
potentiation.
Synaptic Plasticity: Long-Term
Potentiation and Long-Term
Depression
• nitric oxide synthase
– An enzyme responsible for the production of nitric
oxide.
• long-term depression (LTD)
– A long-term decrease in the excitability of a neuron to a
particular synaptic input caused by stimulation of the
terminal button while the postsynaptic membrane is
hyperpolarized of only slightly depolarized.
Perceptual Learning
• short-term memory
– Memory for a stimulus or an event that lasts for a short
while.
• delayed matching-to-sample task
– A task that requires the subject to indicate which of
several stimuli has just been perceived.
Instrumental Conditioning
and Motor Learning
• medial forebrain bundle (MFB)
– A fiber bundle that runs in a rostral-caudal direction though the
basal forebrain and lateral hypothalamus; electrical stimulation of
these axons is reinforcing.
• ventral tegmental area (VTA)
– A group of dopaminergic neurons in the ventral midbrain whose
axons form the mesolimbic and mesocortical systems; plays a
role in reinforcement.
• nucleus accumbens
– A nucleus of the basal forebrain near the septum; receives
dopamine-secreting terminal buttons from neurons of the ventral
tegmental area and is thought to be involved in reinforcement
and attention.
Relational Learning
• anterograde amnesia
– Amnesia for events that occur after some disturbance to the
brain, such as head injury or certain degenerative brain diseases.
• retrograde amnesia
– Amnesia for events that preceded some disturbance to the brain,
such as a head injury or electroconvulsive shock.
• Korsakoff ’s syndrome
– Permanent anterograde amnesia caused by brain damage resulting
from chronic alcoholism or malnutrition.
• confabulation
– The reporting of memories of events that did not take place
without the intention to deceive; seen in people with Korsakoff ’s
syndrome.
Relational Learning
• perirhinal cortex
– A region of limbic cortex adjacent to the hippocampal
formation that, along with the parahippocampal cortex,
relays information between the enthorhinal cortex and
other regions of the brain.
• parahippocampal cortex
– A region of limbic cortex adjacent to the hippocampal
formation that, along with the perirhinal cortex, relays
information between the entorhinal cortex and other
regions of the brain.
Relational Learning
• episodic memory
– Memory of a collection of perceptions of events
organized in time and identified be a particular context.
• semantic memory
– A memory of facts and general information.
• semantic dementia
– Loss of semantic memories caused by progressive
degeneration of the neocortex of the lateral temporal
lobes.
LTP seems to be dependent on the
presence of:
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Which part of the brain is
best known for identifying
social emotions?