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Learning and Memory Animal in Nature Behavior enhances its chance of surviving and reproduction natural selection :- a mechanism for producing behavior suited to environment condition ( adaptation ) or adaptation -- natural selection shape the behavior for state function
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Animal in Nature • Behavior enhances its chance of surviving and reproduction • natural selection :- a mechanism for producing behavior suited to environment condition (adaptation) • or adaptation -- natural selection shape the behavior for state function • adaptation -- may include traits with known genetic cause, also inherited potential for learning
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Definition of Learning “A change in the strength or probability of a behavior because of experience” • Only the right sort of experience counts, not something that “happen to you” • e.g., losing a leg does not count • Only the right sort of causes count • e.g., not sensory adaptation (eye getting used to dark • e.g., not fatique (muscle fatique)
Form of Learning • Non - associative learning • Associative learning • Latent learning • Social learning • Taste learning
Non-associative Learning • Animal are constantly learning about the stimuli in their environment • simplest form of learning, learning about single event • 2 formsof non - associative learning • habituation • sensitization
Habituation • A response decrement with repeated stimuli • primitive form of learning • adaptive value :- save energy and attentional resources • animal learn to attend to stimuli that are important to them, and to ignore stimuli that are not • “spontaneous recovery” • sensory adaptation, fatique???
Sensitization • A response increase after a new or noxious stimulus • e.g., loud noise -- startle animal, cause it move away from the sound • less stimulus - specific --> change stimulus, lead to sensitization • “desensitization” :- extreme reaction to specific stimulus can be sensitized --> reaction diminish
Sensitization • “desensitization” :- • 1st step, low level of stimulus --> habituation would occur rapidly • 2nd step, spontaneous recovery, then increase intensity of stimulus
Associative Learning • 2 forms of associative learning • Classical conditioning or Pavlovian conditioning • Operant conditioning or Instrumental conditioning • both :- learning relation between events (E1, E2, E3, … etc)
Classical Conditioning • Involves learning about relations between 2 or more stimuli in the environment • E1 = a neutral stimuli • E2 = a “reinforcing event”
Classical Conditioning Unconditioned stimulus“meat” Unconditioned response“salivation” Conditioned stimulus“light, tone, experimenter” Conditioned stimulus“salivationight, excitement”
Classical Conditioning • Oxytocin in response to the the jangling of milking equipment • A pet animals fear reaction to the smell of veterinary hospital • or to the sight of a person in a white coat
Operant Conditioning • Animal learning involve learning in 2 relations • Stimulus - stimulus relations • Response - sequence relations • usually mean, animal learns to associate its behavior with the consequence of the behavior • E1 = an action • E2 = consequence of E1
Operant Conditioning Unconditioned Stimulus Unconditioned Response Consequence Sit Eating food treat Food treat held in front of nose Conditioned Stimulus Conditioned Response Consequence Sit Eating food treat Verbal command “sit”
Operant Conditioning • Instrumental condition, there are 4 types of response consequence relation • positive reinforcement : a reward = food, social contact • positive punishment • negative reinforcement : aversive stimuli (dog trainer) • negative punishment
Reinforcement Staying and Punishing Nipping Positive Negative (addition of stimulation) (removal of stimulation) Quiet praise, petting and Food treats provided while Maintaining sit-stay; move ments out of position are ignored Collar jerks, verbral reprimands given when ever dog moves from sit-stay and terminated when dog maintains stay Reinforcement (increases behavior) Punishment Physical correction(muzzle shake, swat) or verbral reprimands when puppy begins to nip Removal of interaction with owner And cessation of play when puppy begins to nip (decreases behavior)
Latent Learning • Differs from associative learning in 2 ways • no survival event • delay expression
Social Learning • Learning by observation of conspecific animal • mechanism • stimulus or local enhancement • social facilitation or social contagion
Conditioned Taste Aversion • “bait shyness” • learn to avoid food that it associates illness, particularly GI • practical application :- LiCl was injected into sheep, resulted in a definite aversion of live or dead lamb by the coyotes
Other type of learning • “chaining” :- the performance of a series of operant response in sequence • many dog owners inadvertently chain obedience commands • with the result that the dog sits, shakes, lies down, and roll over, when owner says, “sits” • “discrimination learning” • “conceptual learning” :- highest type of learning
Other type of learning • “imprinting” :- the special process that • only occur during a definite and short period of the animal’s life • is irreversible • involves an attachment to an object that will later evoke adult behavior pattern :- sexual behavior • involves reactions to particular object that can be generalized to all object (all human or all duck decoys)
Other type of learning • “imprinting” :- occurs most commonly in bird and involves a following response • duckling follow their mother because she is the first moving object they see • if a red ball is the 1st moving object - they follow that
Formation and strengthening of a learned task • “shaping” :- teaching an animal an operant task • circus horse • train animal to perform complicated and relatively unnatural tricks (reinforce with foods award and reinforced for each correct response at first) • reinforcement schedule • rewarded, after every response, after every 10, 20, ... Response • these schedule called “fixed ratios” (FR) • higher FR, the faster response
The frequency with which rewards are offered is called the reinforcement schedule
Physiological Basis of Learning • Anatomy of Learning • hippocampus :- very important in human for consolidation (formation of long-term memory from short-term memory) • lose of hippocampus tissue -- impair feline learning • in dog, frontal lobectomy -- abolished retention of previously learned task • lesion of theventromedial hypothalamus -- improve learning of a conditioned avoidance in cat
Biochemical of Learning • Learning appears to take place in 2 stages • formation of short-term memory • consolidation (formation of long-term memory trace) • time required for formation of long-term memory (vary with species tested, the task learned) • electroconvulsion shock or anesthesia -- inhibit short-term memory
Biochemical of Learning • Short-term memory is the result of following steps :- • the receptor act through transducing protein • activate amplifier enzyme e.g., adenylate cyclase • elevate the levels of intracellular messengers (cAMP) • activate protein kinase • modify target protein e.g., K-channel, modulating neuronal excitability and transmitter release...
Biochemical of Learning • Short-term memory is the result of following steps :- (cont) • cytoplasmic signal (such as cAMP) generated by transmitter-mediated process --> inducer of gene expression (if signal persist long enough) • induced proteins of these genes (basis of long - term memory) • “puromycin”, inhibit protein synthesis, interfere long - term memory
Sleep and Learning • REMS increase when an animal is learning a complex task • deprivation of sleep --> impairs retention of memory
Comparative Intelligence • Which animal species is the smartest? • Methods of measurement • brain size and intelligence • brain weight / body weight ratio • ratio decrease in order :- human 2%, cat 1%, mongrel dog 0.5%, rat 0.3%, goat 0.3%, horse 0.1%, and pig 0.05%
Problems of Cross-Species Comparision • Learning Rates • Classical Conditioning • Delayed Response Method • Multiple Choice Method • Avoidance-Response Method • Maze Learning
Learning Rates • Measured by comparing learning rates of various species on the same task • the task must be physically possible for all species tested
Classical Conditioning • Produce leg flexion in response to the condition stimuli, the sound • pig were the most easily conditioned of the farm animals followed by goats, sheep and rabbits
Learning in Domestic Animal • Pigs • Liddel et al., 1934 : pigs were easier to classically condition than small ruminant or rabbits • sex, breed and age difference • Durocs learn avoidance more quickly than Hampshires • Yorkshires perform better in a T-maze than Poland Chinas (X breed)
Learning in Domestic Animal • Pigs (cont) • sex, breed and age difference • female perform better than male • operant condition • visual discrimination • pigs -- have color vision similar or slightly superior than human • pig can discriminate between wavelength of light differing by only 25 mm
Learning in Domestic Animal • Dogs • Housebreaking • 1st task, all pet must learn -- voluntary control of the anal and urinary sphincters • immediately after meal, gastrocolic reflex increase motility of the large colon and rectum • result in filling the rectum --> stimulate relaxation of the smooth muscle of the external sphincters