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LEARNING and MEMORY Genes (Instinct) European Ethologists Learning Behavior American Psychologists humans learn Which animals learn? ALL? (Def.) Learning is a relatively long-lasting modification of behavior due to experience or practice. Can We Generalize?? What types of animals rely more on instinct? What types strongly benefit from their ability to learn? New Caledonian Crow Magpie SUPER-SMART … CONSCIOUS?? Scrub Jay Parrot Instinctual Behavior GENES … - endow every animal with behavioral potential - determine an animal’s sensory world - determine an animal’s capacity to learn MEMORY Learning requires it! short-term … long-term memory Examples of animal long-term memory?? Migrating Pacific salmon Salmon life cycle END BEGIN Recall Memory Formation We’ll consider the following types of learning: - habituation “nonassociative learning” - classical conditioning “associative learning” - operant conditioning - avoidance learning - imprinting - spatial learning - cultural = observational learning Learning Type 1: Habituation Fading of an unlearned response to a novel stimulus that proves safe or irrelevant. (Requires repetitive exposure to the stimulus) EXAMPLES ?? EXAMPLE: Peckham & Peckham (1894) struck a tuning fork in front of an orb-weaving spider. Habituation as a factor in predation?? Predator Prey Response to Threatening Stimuli Nereis a marine annelid living in sediments WATER OCEAN FLOOR Response to Threatening Stimuli Nereis a marine annelid living in sediments WATER OCEAN FLOOR Habituation of Nereis to 2 stimuli Stimulus-specificity % of Worms Reacting . Time-sensitivity EXAMPLE: YCP Senior Thesis by Becky Brown Were Tyler Run minnows at the road crossing habituated to car spray? crossing vs downstream minnows’ reactions to spray car spray zone car crossing TYLER RUN pool HUMANITIES YCP Blacknose Dace Becky with Supersoaker Record Swimming Activity - before spray - after spray BECKY’S DATA Swimming Activity Reaction of YCP Tyler Run Minnows to a water spray disturbance Road-crossing Minnows Downstream Minnows 35 30 25 Recovery 20 15 10 No Recovery 5 0 0 2 4 6 8 10 12 14 16 18 20 Minutes Minutes Water Spray Aplysia - Behavioraly simple - Simple nervous system - Large neurons - Hardy/inexpensive Learning Research Focus on synaptic efficacy = amplitude of EPSP in response to a pre-synaptic AP Some synapses may show antifacilitation Aplysia Habituation Learning in Aplysia HABITUATION Habituation Aplysia circuitry (siphon) Reason: less transmitter Antifacilitation http://www.sumanasinc.com/webcontent/animations/neurobiology.html SENSITIZATION Head or (from siphon skin) Stays open longer more transmitter release (for gill withdrawal) Restored Excitation Learning Type 2: Classical Conditioning Neutral stimulus US = meat powder UR = salivation CLASSICAL CONDITIONING Vocab Stimulus (= Unconditioned Stimulus) Neutral Stimulus Response (= Unconditioned Response) + US UR training “Neutral” Stimulus (= conditioned stimulus) CS “UR” (= conditioned response) CR Simple nervous systems are capable of - classical conditioning - operant conditioning McConnell’s Flatworms Planaria Learning Type 3: Operant Conditioning (= trial & error learning = instrumental learning) Animal comes to associate its behavior with the consequences of the behavior. Consequences are either … 1)something good (e.g., food) 2)something bad (e.g., electric shock) B.F. Skinner - Helped popularize behaviorism - Operant conditioning pioneer - Invented the Skinner Box to study learning BAR-pressing is the task (+) reinforcement = food pellets (-) reinforcement = electric current https://www.youtube.com/watch?v=PQtDTdDr8vs Behavior can be shaped by reinforcing successive approximations + Operant Conditioning in Flatworms Learning Type 4: Avoidance Learning Recognizing, from experience, a dangerous or unpleasant situation and avoiding it. Most-studied example: Conditioned Taste Aversion (CTA) Animal associates discomfort or illness with food/drink Result: future encounters with that food will be avoided. CTA Demonstration 1) Animal shows a willingness to consume a flavored drink. 2) Animal samples the drink … then is made sick. 3) After recovery, animal declines opportunities to consume the drink. 1-trial learning!! POWERFUL !! Examples?? Rats avoiding poison Predators avoiding … monarch butterflies some toads gila monster lizards Rehnberg & Cassolet Rehnberg & Sherry Your own experience? Eggs Cannot Thermoregulate !! Brood Patch Post-doc Taste Research at the UCONN Health Center Q: How do hamsters perceive sweet tastes? Strategy: CTA Methodology Rejex-it® Migrate (formerly AG 36) is a tool for the behavior modification of Canada geese (Branta Candensis). As a taste aversion agent, Rejex it Migrate changes the taste of the grass to become unpalatable to geese. This causes the geese to leave the area completely to find better feeding and living conditions. Rejex-it® Migrate is only distasteful as long as the grass remains treated. The effect is not systemic, so as the grass grows retreatment is needed to maintain control. Not CTA 3 Nobel Laureates in 1973!! Learning Type 5: Imprinting Learning Type 5: Imprinting A rapid and irreversible attraction or affiliation to an organism(s) or place that happens early in life. Filial Imprinting Critical Period Konrad Lorenz & water fowl Imprinting Reversal HOME IMPRINTING Salmon Hatchery Imprinting to odors of natal stream Critical Period?? SMOLT STAGE Pacific Ocean (Reproductive Migration of Pacific Salmon) Salmon River Hatchery Learning Type 6: Spatial Learning Recognizing and remembering features of home area or territory to allow accurate movements. Widespread ... • Animals that leave nest to find food or mates and then return home • Animals that store food must find it later Simple Spatial Learning ? Morris Water Maze Test for spatial memory The Barnes Maze Finding Stored Food Family Corvidae (crows & jays) are powerful spatial learners Example: Clark’s Nutcracker High mountain habitat: Must find stored seeds in winter Find food ……… Cache (hide) it ………. Find it later Clark’s Nutcracker … requires memory of location … which resulted from spatial learning. MEMORY DEMONSTRATION EXPERIMENT Large room … 330 holes in floor central feeder rocks, logs, etc. on floor Bird allowed to cache seeds in holes on Day 0 9.5 months !! On Days 11, 82, 183, & 285 birds did better than random!! …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. F …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. …………………………………………….. OK … where did I park my car 15 minutes ago? Seed Caching in 3 Species of Western Corvids (crows) Species Elevation Clark’s nutcracker highest Winter diet 100% cached Cached seeds/yr 33,000 Pinyon jay middle 70-90 20,000 Scrub jay lowest ?? 6,000 M E M O R y (remembering locations on a computer monitor) M E M O R y (remembering colors on a computer monitor) Spatial memory region in the brain?? HIPPOCAMPUS (Birds & Mammals) Clark Nutcrackers After bilateral lesions of the hippocampus, caching behavior is normal ……. but retrieval is lost!! Published YCP Thesis Test Arena for Spatial Memory of Gerbils Better-than-chance performance at day 110 * * Chronically-implanted electrode in a place cell Place cells are hippocampal neurons that fire when animal is in a specific part of a familiar spatial area 2 3 4 5 1 6 7 Simultaneous recordings from 7 place cells in the CA1 layer of the rat hippocampus. Recorded while the rat ran hundreds of laps around a triangular track. The rat stopped in the middle of each side to eat rewards. Black dots show position of head … colors represent responses by different place cells. Learning Type 6: Cultural Learning (= observational learning) Learning by observing what another animal is doing. Learning by "copying". BUT…….. it’s more than momentary imitation. The learned behavior may appear some time after the original observation(s). EXAMPLE: Imo was a female Japanese macaque that was the source of new food-cleaning techniques. Imo introduced washing sweet potatoes to remove grit. She also introduced the washing of wheat grains: float them and the grit sinks. These behaviors spread slowly through the group. passage from Drickamer, p. 177 http://www.arkive.org/japanese-macaque/macaca-fuscata/video-08c.html E X A M P L E Blackbirds Australian honey guide Blackbird Learning Type 4: Insight Learning https://mail.google.com/mail/u/0/#inbox/15a1e3cb2ff62535?projector=1 Insight Learning Formulating new behaviors or solutions to problems by thinking about them. May require making mental models or simulations to discover hypothetical outcomes - Most advanced? - Consciousness? - Taxonomically limited - Animal evidence limited & controversial Insight Learning Kohler’s chimps New Caledonian Crow Insight Learning? Operant Conditioning? “Mere” Instinct? Preparedness Preparedness is an animal's genetically-determined predisposition to learn. Preparedness is task-specific and species-specific. Example: Rat preparedness - Prepared: taste aversion comes very easy for rats. - Unprepared: learning a complex bar-pressing protocol to receive food pellet. (takes training) - Contraprepared: pressing levers to avoid electric shock. Rats are prepared to run when shocked. The END