PSY402 Theories of Learning Friday March 14, 2003

Limits to Learning  How general are the laws of learning? Skinner’s rules work in both lab and real-world settings, across species.  Learning doesn’t explain all aspects of behavior. Organization of behavior already exists within an organism. Learning modifies that organization.

Behavior Systems Approach  Timberlake – learning changes the integration, tuning, instigation or linkages within a behavior system. Different cues are salient to different behavior modes. Variations in learning occur across species because their behavior systems are different.  Variations in behavior are the result of predispositions and constraints.

Animal Misbehavior  Breland & Breland – trained 38 species of animals for Busch Gardens.  Elicitation of foraging and food- handling instincts interferes with performance of operant routines. Instinctive drift Pig and piggy bank Raccoons and food-washing

Explaining Misbehavior  Does misbehavior result from operant food reinforcement or classical conditioning?  Timberlake’s appetitive structure view – both kinds of learning contribute to animal misbehavior. Pairings with food are necessary but not sufficient to evoke misbehavior.

Schedule-Induced Behavior  Superstitious behavior – induced by FI schedules. Animal associates whatever it is doing at the time with the reinforcement. Ritualistic, stereotyped behavior during the interval.  Two kinds of behavior: Terminal – reinforcer-oriented Interim – follows reinforcement.

Effects with Humans  Superstitious gambling behavior.  Schedule-induced behavior may be related to alcoholism: Excessive drinking, eating, smoking may occur immediately after reinforcement.  Weak and inconsistent in humans. Develops rapidly in humans, stops quickly

Flavor-Aversion Learning  Long-delay learning – does not depend on contiguity.  Preparedness – certain stimuli are innately more likely to be associated with a UCS than others. Visual cues more salient to birds Taste cues more salient to rats Salience depends on when the animals seeks its food (nocturnal or not).

Applications  Cancer chemotherapy (UCS) causing nausea may be associated with hospital food (CS). Preexposure to food without the toxic drug or drug without food may help prevent food aversions.  Coyotes and wolves can be taught to avoid attacking and eating sheep using flavor-aversion learning.

Explanations  Learned-Safety theory – an evolved mechanism unique to flavor- aversion to protect animal. Ingestional neophobia – small quantities consumed at first.  Concurrent-Interference view – long delay occurs because the animal doesn’t eat anything else for a while

Imprinting  Lorenz – social attachment process where young ducks follow their mother.  Ducks imprint to: Moving objects with lifelike motion Vocalizing objects, short rhythmic sounds, not high-pitched Objects that are the right size

Other Factors in Imprinting  Harlow – baby primates attach to soft terry cloth rather than wire. Rocking rather than stationary Warm rather than cold  Ainsworth – attachment to a responsive mother.  Occurs more easily during sensitive period of animal’s life. 6 to 12 months for humans

Other Kinds of Imprinting  Sexual preferences – occurs early in development, long before sexual maturity, not modifiable later.  Food preferences – preferences established early and permanent. People prefer familiar foods Food aversions develop between 6 & 12 yrs

Nature of Imprinting  Both instinctive and associative processes are involved.  Associative-learning view – objects become familiar before fear system matures Familiar objects reduce fear later, so become preferred due to relief.  Harlow’s studies contradict this.  Some objects are more imprintable.

Instinctive View of Imprinting  Organisms contain an innate schema of the imprinting object Evoluntary pressure to learn the right thing.  Response is hard to change. Extinction does not lead to loss of preference. Abused primates and children cling to abusive mothers despite punishment.

Avoidance of Aversive Events  Species-specific defense reactions (SSDR) – instinctive responses to specific dangers.  Rats – running, freezing, fighting.  Cues predicting danger also select the specific response. Escape and avoidance behaviors are learned more readily when they incorporate SSDR.