Chapter 12

The Limitations of Learning

Physical Characteristics

• Physiological structure of the species

• Limitations on behaviours

Nonheritability of Learned Behaviour

• Learned behaviours are not inherited

• Lamarckian evolution: passing acquired characteristics to offspring

• William McDougall: trained on tasks for many generations

• Failure to replicate results

• Inheritance of learning could limit adaptability

Heredity and Learning Ability

• Genetic influences on ability to learn• Not the same as inheriting learned behaviours• Tryon (1940): rats learn maze, breed

“smartest” together and “dumbest” together for 18 generations

• Identical twins reared apart• Nature and nurture

Neurological Damage

• Neurotoxins

• Prenatal damage to CNS (e.g., fetal alcohol syndrome, crack cocaine)

• Environmental toxins (e.g., lead)

• Physical damage (e.g., concussions)

Critical Periods

• Stage for optimum learning

• Imprinting

• Konrad Lorenz

• Puppy dogs

• Harlow (1958, 1962) studies: terry cloth monkey moms

Biological Preparedness

• Species specific influences on behaviour

• Genetic predispositions

• Assist or hinder acquisition of behaviour

• Retention of behaviour

Instinctive Drift

• Breland & Breland (1961)

• Pig, raccoon

• Operant task

• Reinforcer

• Early in training

• Later in training

Autoshaping• Brown & Jenkins (1968)

• Key pecking with pigeons

• VT-60 grain delivery

• Light on 8 seconds before food delivery

• No response necessary…

• But pigeons started pecking light