PSY402Theories of Learning

Chapter 12 (pg 303-327)Biological Influences on Learning

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.