psychology 250 lecture 12 kevin r smith. three types of behavior reflexes: involuntary responses to...
TRANSCRIPT
Three Types of BehaviorThree Types of Behavior Reflexes: involuntary Reflexes: involuntary
responses to stimuliresponses to stimuli Instincts: stereotyped Instincts: stereotyped
responses triggered responses triggered by environmental by environmental stimulistimuli
Learning: a relatively Learning: a relatively permanent change in permanent change in behavior due to behavior due to experienceexperience
© Renee Purse/Photo Researchers, Inc.
Types of LearningTypes of Learning
Nonassociative learning: a change in Nonassociative learning: a change in the magnitude of response to the magnitude of response to environmental eventsenvironmental events• HabituationHabituation• SensitizationSensitization
Associative learning: a connection Associative learning: a connection between two elements or eventsbetween two elements or events• Classical conditioningClassical conditioning
Habituation and SensitizationHabituation and Sensitization Habituation Habituation
• The response to steady or repeated The response to steady or repeated stimulus decreases over timestimulus decreases over time
• Example: You don’t hear your air Example: You don’t hear your air conditioner after it’s been running awhileconditioner after it’s been running awhile
SensitizationSensitization• The experience of one stimulus heightens The experience of one stimulus heightens
the response to a subsequent stimulusthe response to a subsequent stimulus• Example: People are “jumpy” following Example: People are “jumpy” following
natural disasters, like earthquakesnatural disasters, like earthquakes
Classical Conditioning and PavlovClassical Conditioning and Pavlov
Dogs eating habitsDogs eating habits• Noticed that the dogs salivate prior to Noticed that the dogs salivate prior to
getting their foodgetting their food• Measured the amount of salivation that Measured the amount of salivation that
occurs when the dogs are anticipating occurs when the dogs are anticipating foodfood
Anticipation cues were Pavlov at firstAnticipation cues were Pavlov at first• Changed to a toneChanged to a tone
Pavlovian ConditioningPavlovian Conditioning
Before TrainingBefore Training• No salivation to a toneNo salivation to a tone• Salivation to meat onlySalivation to meat only
After TrainingAfter Training• Salivation to a toneSalivation to a tone
Classical ConditioningClassical Conditioning
A conditioned stimulus (CS) is an initially A conditioned stimulus (CS) is an initially neutral stimulus that acquires the ability neutral stimulus that acquires the ability to signal important biological eventsto signal important biological events
An unconditioned stimulus (UCS) is an An unconditioned stimulus (UCS) is an event that elicits a response without prior event that elicits a response without prior experienceexperience
A conditioned response (CR) is a learned A conditioned response (CR) is a learned reaction to a CSreaction to a CS
An unconditioned response (UCR) is an An unconditioned response (UCR) is an unlearned reaction to a UCSunlearned reaction to a UCS
Using Using Aplysia Californica Aplysia Californica to Study to Study Learning Learning
The gill is used for The gill is used for breathingbreathing
The gill can be covered with The gill can be covered with the mantle shelfthe mantle shelf
Waste and seawater are Waste and seawater are released through the siphonreleased through the siphon
The gill-withdrawal reflex The gill-withdrawal reflex occurs when touching the occurs when touching the siphon produces a siphon produces a retraction of the gillretraction of the gill• Touching the siphon Touching the siphon
repeatedly yields a repeatedly yields a decrease in the gill decrease in the gill withdrawal reflex: withdrawal reflex: HabituationHabituation
Eric Kandel and Habituation in Eric Kandel and Habituation in AplysiaAplysia
The siphon is served by 24 sensory The siphon is served by 24 sensory neurons, whose cell bodies are in the neurons, whose cell bodies are in the abdominal ganglionabdominal ganglion
Siphon sensory neurons form Siphon sensory neurons form synapses with:synapses with:• excitatory and inhibitory interneuronsexcitatory and inhibitory interneurons• six motor neurons serving the gillsix motor neurons serving the gill
Possible Hypotheses for Possible Hypotheses for HabituationHabituation
Do sensory neurons become less responsive?Do sensory neurons become less responsive?• Single cell recordings from sensory neurons did not decrease Single cell recordings from sensory neurons did not decrease
with repeated touching of the siphonwith repeated touching of the siphon
Daniel L. Geiger/SNAP
More HypothesesMore Hypotheses
Does the gill muscle lose its ability to Does the gill muscle lose its ability to contract?contract?• Electrical stimulation of the motor Electrical stimulation of the motor
neurons produced muscle contraction, neurons produced muscle contraction, even after habituationeven after habituation
Do changes occur at the synapses Do changes occur at the synapses between the sensory and motor between the sensory and motor neurons?neurons?
Kandel’s Explanation of Kandel’s Explanation of HabituationHabituation
Repeated siphon touches Repeated siphon touches reduce entry of calcium reduce entry of calcium into sensory neurons, into sensory neurons, which release less which release less neurotransmitterneurotransmitter
Smaller EPSPs occur in Smaller EPSPs occur in interneurons and motor interneurons and motor neuronsneurons
Motor neurons produce Motor neurons produce weaker response, leading weaker response, leading to less gill withdrawalto less gill withdrawal
AplysiaAplysia also show sensitization also show sensitization
After a electrical shock to the head or After a electrical shock to the head or tail, there is an increased gill-tail, there is an increased gill-withdrawal response when the withdrawal response when the siphon is touchedsiphon is touched
Sensitization in Sensitization in AplysiaAplysia
Shocking the tail stimulates Shocking the tail stimulates interneurons that form synapses with interneurons that form synapses with sensory neurons serving the siphonsensory neurons serving the siphon
Sensory neurons release more Sensory neurons release more neurotransmitter onto motor neurotransmitter onto motor neurons, and the gill retracts stronglyneurons, and the gill retracts strongly
Long-term ChangesLong-term Changes
Normal Normal Aplysia Aplysia showed showed 1300 axon terminals on 1300 axon terminals on sensory neuronssensory neurons
Aplysia Aplysia experiencing experiencing sensitization had sensitization had 2800 terminals2800 terminals
Aplysia Aplysia experiencing experiencing habituation had 800 habituation had 800 terminalsterminals
Classical Conditioning in Classical Conditioning in AplysiaAplysia
Electrical shock to the tail leads to Electrical shock to the tail leads to gill-withdrawal reflexgill-withdrawal reflex
Touching the mantle alone does not Touching the mantle alone does not trigger anythingtrigger anything
Pairing the mantle with the shock Pairing the mantle with the shock leads to gill-withdrawal reflexleads to gill-withdrawal reflex
After learning, touching the mantle After learning, touching the mantle alone leads to gill-withdrawal reflexalone leads to gill-withdrawal reflex
Mechanisms for Classical Mechanisms for Classical ConditioningConditioning
Touching the mantle leads to NT releaseTouching the mantle leads to NT release• Amount released is too small to get a gill-Amount released is too small to get a gill-
withdrawal reflexwithdrawal reflex Touching the tail leads to an increase in Touching the tail leads to an increase in
the NT released at the gill-withdrawal the NT released at the gill-withdrawal reflexreflex
After frequent pairingsAfter frequent pairings• More NT is released when the mantle is More NT is released when the mantle is
touched by itselftouched by itself
Conditioned Emotional Conditioned Emotional Responses and the AmygdalaResponses and the Amygdala
Typical Paradigm:Typical Paradigm:• Tone (CS+) followed by shock (UCS) results in Tone (CS+) followed by shock (UCS) results in
reduced feeding (CR) in ratsreduced feeding (CR) in rats Recording during training shows an increased Recording during training shows an increased
response of the amygdala to the toneresponse of the amygdala to the tone Lesions of the basolateral nucleus of the Lesions of the basolateral nucleus of the
amygdala prevent the learning of emotional amygdala prevent the learning of emotional responsesresponses
Blocking NMDA receptors in the amygdala Blocking NMDA receptors in the amygdala prevents learning of conditioned emotional prevents learning of conditioned emotional responsesresponses
Thus: the amygdala is involved in Classical Thus: the amygdala is involved in Classical ConditioningConditioning
Learning and the CerebellumLearning and the Cerebellum
Cerebellum is involved in motor Cerebellum is involved in motor controlcontrol
Also probably involved in motor Also probably involved in motor learninglearning
Highly complex network of neurons Highly complex network of neurons controls learningcontrols learning
Long Term DepressionLong Term Depression
Long term depressionLong term depression• A weakening of a synapse that lasts hours A weakening of a synapse that lasts hours
or daysor days• Thought to be associated with learningThought to be associated with learning• Found in the cerebellum and hippocampusFound in the cerebellum and hippocampus
Long term potentiationLong term potentiation• A long lasting strengthening of a synapseA long lasting strengthening of a synapse• Thought to be associated with memoryThought to be associated with memory
Classical Conditioning of the Classical Conditioning of the Rabbit’s Nictitating MembraneRabbit’s Nictitating Membrane
A tone (CS) followed by a puff of air A tone (CS) followed by a puff of air to the eye (UCS) leads to closure of to the eye (UCS) leads to closure of the nictitating membrane (UCR)the nictitating membrane (UCR)
Activity in the lateral interpositus Activity in the lateral interpositus nucleus (LIP) of the cerebellum nucleus (LIP) of the cerebellum increases in response to the tone increases in response to the tone over trialsover trials
Human Research and the LIPHuman Research and the LIP
Humans learn classically conditioned Humans learn classically conditioned eyeblink responseseyeblink responses
PET scans show increased cerebellar PET scans show increased cerebellar activity during classical conditioningactivity during classical conditioning
Individuals with cerebellar damage Individuals with cerebellar damage have difficulty learning conditioned have difficulty learning conditioned eyeblink responseseyeblink responses
MemoryMemory
Memory refers to the storage and Memory refers to the storage and retrieval of informationretrieval of information
No absolute boundaries between No absolute boundaries between learning and memorylearning and memory
Learning and memory may be Learning and memory may be viewed as a continuumviewed as a continuum
Locating the Memory Trace Locating the Memory Trace (Engram)(Engram) Karl Lashley Karl Lashley
observed the effects observed the effects of lesions on rats’ of lesions on rats’ maze learningmaze learning
The larger the The larger the amount of cortex amount of cortex damaged, the more damaged, the more errors the rats madeerrors the rats made
Lashley believed Lashley believed that the engram that the engram was distributed was distributed across the cortexacross the cortex
Brain Stimulation and MemoryBrain Stimulation and Memory Wilder Penfield stimulated the cortex of Wilder Penfield stimulated the cortex of
patients undergoing surgery for epilepsypatients undergoing surgery for epilepsy 8% of the patients experienced specific 8% of the patients experienced specific
memories when their temporal lobes memories when their temporal lobes were stimulatedwere stimulated
Lead to the theory that memories could Lead to the theory that memories could be localized in the brainbe localized in the brain
Penfield’s results may have been Penfield’s results may have been influenced by the patients’ epilepsyinfluenced by the patients’ epilepsy
Patient H.M. and MemoryPatient H.M. and Memory Large areas of H.M.’s Large areas of H.M.’s
temporal lobes were temporal lobes were surgically removedsurgically removed
H.M.’s personality and H.M.’s personality and IQ were not affectedIQ were not affected
H.M. experienced H.M. experienced profound anterograde profound anterograde amnesiaamnesia• Inability to learn new Inability to learn new
informationinformation
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RetrogradeRetrograde• Loss of memories of the pastLoss of memories of the past
AnterogradeAnterograde• Inability to form new memoriesInability to form new memories
H.M.’s Memories Are Not Equally H.M.’s Memories Are Not Equally AffectedAffected
Short-term Short-term memory allowed memory allowed H.M. to converseH.M. to converse
H.M. retained the H.M. retained the ability to learn ability to learn procedural tasksprocedural tasks
H.M.’s deficits H.M.’s deficits appear in explicit appear in explicit memory tasksmemory tasks
The Delayed Nonmatching to The Delayed Nonmatching to Sample TaskSample Task
Monkeys with Monkeys with medial temporal medial temporal lobe damage do lobe damage do poorly on the poorly on the DNMS taskDNMS task
The DNMS task The DNMS task requires the requires the ability to form ability to form long-term long-term memoriesmemories
Conclusion thus farConclusion thus far
The amygdala and the cerebellum The amygdala and the cerebellum seem to play a role in forming seem to play a role in forming associations (very basic learning)associations (very basic learning)• Animal studiesAnimal studies
The temporal lobe seems to play The temporal lobe seems to play some role in memoriessome role in memories• HM and MonkeysHM and Monkeys
What about the Hippocampus?What about the Hippocampus?
The Hippocampus and The Hippocampus and MemoriesMemories
HM had major lesions to his HM had major lesions to his hippocampushippocampus• Anterograde anmesiaAnterograde anmesia
LTP occurs in the hippocampusLTP occurs in the hippocampus LTP results when synapses become LTP results when synapses become
more efficientmore efficient LTP can be demonstrated indefinitely LTP can be demonstrated indefinitely
in living animals and for hours in slices in living animals and for hours in slices of hippocampusof hippocampus
LTP Shares Characteristics with LTP Shares Characteristics with Long-term MemoryLong-term Memory
Unsure of whether LTP is the mechanism Unsure of whether LTP is the mechanism for Long term memories BUTfor Long term memories BUT• Both LTP and long-term memories last Both LTP and long-term memories last
indefinitelyindefinitely• Both LTP and long-term memories result Both LTP and long-term memories result
from very brief inputfrom very brief input• LTP is consistent with cellular learning LTP is consistent with cellular learning
models proposed by Donald Hebbmodels proposed by Donald Hebb NMDA receptors (Glutamate) closely NMDA receptors (Glutamate) closely
associated with LTPassociated with LTP
The Hippocampus and Human The Hippocampus and Human MemoryMemory
The right hippocampus is active during The right hippocampus is active during spatial memory processing and the left spatial memory processing and the left hippocampus is active during verbal hippocampus is active during verbal memory processingmemory processing
Rostral portions of the hippocampus are Rostral portions of the hippocampus are more active during encoding, and caudal more active during encoding, and caudal portions are active during retrievalportions are active during retrieval
The hippocampus does not store The hippocampus does not store memories, but transfers them from short memories, but transfers them from short to long-term storageto long-term storage
Patient N.A.Patient N.A. A fencing foil A fencing foil
produced a lesion to produced a lesion to N.A.’s left N.A.’s left dorsodorsommedial thalaedial thalammusus
N.A. experienced N.A. experienced profound anterograde profound anterograde aammnesia and sonesia and somme e retrograde aretrograde ammnesianesia
N.A.’s N.A.’s mmeemmory loss ory loss was siwas simmilar to H. ilar to H. MM.’s.’s
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The Diencephalon and MemoryThe Diencephalon and Memory
Korsakoff’s patients show anterograde and Korsakoff’s patients show anterograde and retrograde amnesiaretrograde amnesia• Thiamine deficiencies result from chronic Thiamine deficiencies result from chronic
alcoholismalcoholism• Untreated thiamine deficiencies damage Untreated thiamine deficiencies damage
dorsomedial thalamus and mamillary bodiesdorsomedial thalamus and mamillary bodies Monkeys with lesions in the dorsomedial Monkeys with lesions in the dorsomedial
thalamus have difficulties with the DNMS thalamus have difficulties with the DNMS testtest
Temporal-diencephalic circuits may process Temporal-diencephalic circuits may process long-term memorieslong-term memories
Localization of SeLocalization of Semmantic antic MMeemmoriesories
SeSemmantic antic mmeemmories are widely distributed in the ories are widely distributed in the cortexcortex
Prosopagnosia: inability to recognize common facesProsopagnosia: inability to recognize common faces
Localization of Localization of MemoriesMemories
Encoding and Encoding and retrieval retrieval mmay ay activate different activate different areasareas
Episodic Episodic MMeemmory and the ory and the CortexCortex
Greater right frontal Greater right frontal and teand temmporal activity poral activity is associated with is associated with hearing your own story hearing your own story rather than another rather than another person’sperson’s
In source aIn source ammnesia, a nesia, a patient forgets when patient forgets when and where a and where a mmeemmory ory was forwas formmeded
Episodic Episodic mmeemmory is ory is superior in fasuperior in fammilies ilies where left-handedness where left-handedness is cois commmmonon
Short-terShort-termm MMeemmory and the Cortexory and the Cortex The prefrontal cortex The prefrontal cortex mmay be involved with ay be involved with
short-tershort-termm mmeemmoryory Patients with prefrontal daPatients with prefrontal dammage do poorly on age do poorly on
the Wisconsin card-sorting taskthe Wisconsin card-sorting task Object perObject permmanence anence
tasks:tasks:• Are Are mmastered by infants astered by infants
at the age of 7 or 8 at the age of 7 or 8 mmonthsonths
• Adult Adult mmonkeys with onkeys with prefrontal lesions prefrontal lesions respond like irespond like immmmature ature huhumman infantsan infants
© Bob Daemmrich/Stock, Boston
The Basal Ganglia and The Basal Ganglia and Procedural MemoryProcedural Memory
Lesions of the Lesions of the hippocampus hippocampus impaired declarative impaired declarative memories memories (remember where (remember where you went last time)you went last time)
Lesions of the Lesions of the caudate nucleus caudate nucleus (basal ganglia) (basal ganglia) impaired procedural impaired procedural memoriesmemories
Patients with Patients with Huntington’s Huntington’s disease and disease and Parkinson’s disease Parkinson’s disease have procedural have procedural memory deficits, memory deficits, but not declarative but not declarative memory deficitsmemory deficits
Genetic Manipulation of Genetic Manipulation of Learning AbilityLearning Ability
DrosophilaDrosophila can learn to avoid odors can learn to avoid odors associated with electric shockassociated with electric shock
Blocking the expression of the Protein Blocking the expression of the Protein Kinase A gene prevents learning and Kinase A gene prevents learning and formation of short-term memoriesformation of short-term memories
Too much CREB-2 blocks long but not Too much CREB-2 blocks long but not short-term memoriesshort-term memories
Extra CREB-1 produces immediate Extra CREB-1 produces immediate long-term memorylong-term memory
Unusual Memory PhenomenaUnusual Memory Phenomena RepressionRepression FlashbacksFlashbacks Flashbulb Flashbulb
memoriesmemories Stress affects the Stress affects the
amygdala and amygdala and hippocampus hippocampus
Cortisol may Cortisol may damage the damage the hippocampushippocampus
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Eye Witness TestimonyEye Witness Testimony Beth Loftus: False MemoriesBeth Loftus: False Memories Had students go home and ask younger Had students go home and ask younger
siblings: Hey, do you remember that siblings: Hey, do you remember that time when you got lost in the mall?time when you got lost in the mall?
The siblings had never been lost in the The siblings had never been lost in the mallmall
The siblings conjured up detailed storiesThe siblings conjured up detailed stories Bugs Bunny at DisneylandBugs Bunny at Disneyland
Memory and Normal AgingMemory and Normal Aging
In healthy adults, most measures of In healthy adults, most measures of cognitive ability remain stablecognitive ability remain stable
Memory loss may accompany changes Memory loss may accompany changes in brain systems that utilize the in brain systems that utilize the neurotransmitter acetylcholine (ACh)neurotransmitter acetylcholine (ACh)
Attaining an above-average education; Attaining an above-average education; engaging in complex, non-routine engaging in complex, non-routine professions; and earning high income professions; and earning high income appear to protect against cognitive appear to protect against cognitive declinedecline