PSY 402Learning Enables Adaptation2.1 Eggshell removal in herring gullsFixed Action Patterns2.2 The eyebrow flash in Bali and Papua New GuineaModification of Innate BehaviorsAcquired Changes in Response2.3 Habituation occurs when exposure to a stimulus elicits a response (Part 1)2.3 Habituation occurs when exposure to a stimulus elicits a response (Part 2)2.3 Habituation occurs when exposure to a stimulus elicits a response (Part 3)Instrumental Adaptation2.4 The Law of EffectReinforcementShaping2.5 Shaping introduces new behaviorsClassical Conditioning AdaptationExamples of ConditioningTerritorialityFear ConditioningConditioning and Addictions2.9 The development of drug toleranceSign Tracking (Auto-Shaping)2.11 Sign tracking in Pavlovian learningExtinction2.12 Extinction occurs in instrumental conditioning (Part 1)2.12 Extinction occurs in classical conditioning (Part 2)Timing of Stimuli2.13 Reward and Punishment (Part 1)2.13 Reward and Punishment (Part 2)2.14 Classical conditioning is better when the interval between S and S* is minimal (Part 1)2.14 Classical conditioning is better when the interval between S and S* is minimal (Part 2)2.14 Classical conditioning is better when the interval between S and S* is minimal (Part 3)Size of the Stimuli2.15 Bigger S*s cause better response learning (Part 1)2.15 Bigger S*s cause better response learning (Part 2)2.16 Bigger S*s cause better stimulus learning, too (Part 1)2.16 Bigger S*s cause better stimulus learning, too (Part 2)Preparedness Affects Learning2.17 Preparedness in classical conditioning2.18 Preparedness in instrumental conditioningHumans Show PreparednessPSY 402Theories of LearningChapter 2 – Learning and AdaptationLearning Enables AdaptationThe ability to adapt to one’s environment with experience enhances survival.Those organisms able to adapt were more likely to survive and thus were selected by natural selection.Example of survival value of a behavior:Black-headed gulls and eggshellsKittiwakes who nest on cliffs don’t remove shells2.1 Eggshell removal in herring gullsFixed Action PatternsFixed behavior sequences that are released by an environment signal.Triggered by a releaser, also called a sign stimulusNot learned – built in to the genes, innateStereotyped – occur the same way each time and in each person or organismEibl-Eibesfeldt considered smiling & eyebrow flashing to be a human fixed action pattern.2.2 The eyebrow flash in Bali and Papua New GuineaModification of Innate BehaviorsEven behaviors that are innate can be modified through conditioning.Gull chicks get better at pecking at their parents’ beaks to get food – more accurate.Conditioning experiences can change sensitivity to releasing signs.Conditioning fine tunes the response to the environment and enhances survival.Acquired Changes in ResponseHabituation – response to a repeated stimulus decreases with non-threat experience.Sensitization – response to a variety of stimuli increases with a single threat experience.Examples:Ingestional neophobia, fear of new foodRats orient less toward light, startle decreasesChicks are less frightened by shadows flying overhead with repeated exposure.2.3 Habituation occurs when exposure to a stimulus elicits a response (Part 1)2.3 Habituation occurs when exposure to a stimulus elicits a response (Part 2)2.3 Habituation occurs when exposure to a stimulus elicits a response (Part 3)Instrumental AdaptationInstrumental learning (S-R) occurs when a voluntary behavior (R) becomes associated with a stimulus (S) because of its effect.Consequences can be either rewards or punishments.Rewards and punishments are defined by their effect on behavior.A reward increases behaviorA punishment decreases behavior.2.4 The Law of EffectReinforcementReinforcement occurs when the association between a stimulus and a response to it is strengthened.Positive reinforcement occurs when a behavior is rewarded.Negative reinforcement occurs when a behavior results in avoidance or escape from a bad consequence.ShapingHow can a behavior be reinforced if it never occurs naturally (or accidentally)?Shaping is a process where a complex or unnatural behavior is learned as a series of steps that are successively rewarded.By rewarding successive approximations to the desired behavior, eventually the target behavior is learned.2.5 Shaping introduces new behaviorsClassical Conditioning AdaptationOrganisms learn to recognize and respond selectively to the signals that are important in their environment.Cues associated with food evoke digestion: salivation, gastric juices, insulin secretion.Taste aversion learning – illness makes us avoid foods that were eaten just prior to feeling sick.Food preferences are associated with nutrients.Examples of ConditioningPopcorn at the movies.Fear of flying -- stronger with more turbulence (a stronger UCS).An antelope shying away from low tree branches.Nausea at the smell of alcohol after a hangover.TerritorialityEnvironmental cues can become associated with sexual rival males in gourami fish.Pairing the light with the rival signaled the other fish to prepare so it was able to be more aggressive.Presenting the light without pairing it with the rival had no effect.Courtship behavior can also be conditioned, leading to more successful nestbuilding, etc.Fear ConditioningFreezing is a universal response to threat.Animals that freeze are less likely to be attacked.Fear is an anticipatory pain response. It occurs in response to stimuli that have been aversive in the past and motivates escape or avoidance behaviors.Fear also releases endorphins in rats who are confronted by the smell or sight of a cat.Conditioning and AddictionsDrugs can be associated with environmental cues present when the drugs are taken.Instead of the drug response being conditioned, an opposite adaptive response is conditioned that lessens the drug’s effect.This is called drug tolerance.Taking a drug under novel circumstances can produce a drug overdose because the compensatory effect is not present (no cues).2.9 The development of drug toleranceSign Tracking (Auto-Shaping)Sign tracking occurs when a stimulus (cue) in the environment is associated with reward or punishment.The sign stimulus motivates approach or avoidance behavior because of what it signals.Negative sign
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