PSY402 Theories of LearningExperimental EvidenceConditions Producing ChangeConditions (Cont.)Opponent-Process TheoryThe Addiction ProcessWhat Sustains Addiction?Acquisition of a Conditioned ResponseAcquisition, Extinction, and Spontaneous RecoveryConditioned Emotional ResponsesExamples of ConditioningConditioning SituationsFear conditioningSuppression RatioFlavor Aversion LearningPSY402Theories of LearningMondayJanuary 13, 2003Experimental EvidenceRats drink little saccharin water at first but increase over time.Loud tones (110 db) produce different responses depending on the background noise (60 vs 80 db).Habituation occurred at 60 dbSensitization occurred at 80 dbA loud background is arousing, leading to greater reactivity, not less.Conditions Producing ChangeMore intense (stronger) stimuli produce stronger sensitization, less likely to produce habituation.Greater sensitization and habituation occur when the stimulus is repeated frequently.Changes in the stimulus prevent habituation.Turkeys respond to shape changes.Conditions (Cont.)Sensitization can occur to many kinds of stimuli but habituation occurs only with innate responses.Habituation and sensitization are transient (go away after seconds or minutes between stimuli).Except long-term habituation.Dishabituation – response returns when a sensitizing stimulus occurs.Opponent-Process TheoryAn explanation for addictions.All experiences produce an affective reaction (pleasant or unpleasant) – A state.This reaction gives rise to its opposite – B state.B state is less intense and lasts longer.Over time, the A state diminishes and the B state increases.The Addiction ProcessTolerance – diminished A state.Withdrawal – increased B state.Addictive behavior is a coping response to the change in B state.People try to enhance A state to offset the unpleasantness of the B state.Without withdrawal symptoms there is no addictive behavior.Time prevents B state strengthening.What Sustains Addiction?The B state is a non-specific aversive feeling.Anything similarly aversive will motivate the addictive behavior, even if it has no relation to the substance.Daily life stress produces a B state that results in behavior to create an A state.Parachute jumpers – create a B state in order to feel the A state.Acquisition of a Conditioned ResponseChapter 3, pages 37-46Acquisition, Extinction, and Spontaneous RecoveryConditioned Emotional ResponsesFear is an anticipatory pain response based on past experience.Fear is conditioned whenever a CS is associated with an aversive (painful or negative) event.Fear motivates two responses:Escape (when pain is present)Avoidance (when pain is imminent)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.Conditioning SituationsSign-tracking (autoshaping) – animals must recognize signs of food (UCS) and respond (UCR).Pigeons pecking at key.UCR, not an operant response, because behavior is specific to the stimulus.Eyeblink conditioningUCR is rapid, CR is slow.Many trials are needed (100 pairings)Fear conditioningAvoidance is not a good measure of fear.Suppression of an operant behavior occurs with a feared stimulus.First – an operant behavior is learned.Second – a CS is paired with an aversive UCS.Third – the CS is presented in the operant chamber.Suppression RatioDuring CSSuppressionRatio = During CS + Without CSThe amount of time during and without the CS is equal.The more fear, the lower the suppression ratio.Ratios typically fall between 0 and .5Flavor Aversion LearningGarcia – rats will not drink water with saccharin if they get ill after drinking.Significant avoidance occurs after just one trial.Human food aversions are related to illness (89%).Even if illness occurs hours later it is linked to the previous meal.Not cognitive – know food not to
View Full Document
Unlocking...