The Limitations of Learning

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Chapter 12

• The Limitations of Learning

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Limits

• Physical Characteristics
• Non-heritability
• Heredity of learning ability
• Neurological Damage
• Critical Periods
• Preparedness
• Instinctual Drift
• Biological Preparedness
• Sign Tracking

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Physical Characteristics

• Physiological structure of the species
• Limitations on behaviours
• e.g. teaching chimps to
• talk vs. teaching sign language

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Nonheritability of Learned Behaviour

• Learned behaviours are not inherited
• Lamarckian evolution passing acquired
  characteristics to offspring
• Short neck giraffe needs to stretch to reach food
• Neck gets longer
• Passes on long neck to offspring

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McDougalls rats

• Trained rats to run on avoidance task
• Trained those rats offspring on avoidance task
• Trained those rats offspring on avoidance task,
  etc.
• Each generation should learn faster (inherit
  skill of parents, and ancestors)
• BUT, no control group

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Agar (1954)

• Replicated McDougalls design, but added a
  control group
• Control every second generation was untrained
• Found same pattern of results with control group
• i.e. successive generation also learned faster
  than previous generations
• But also many fluctuations within both groups
• Suggests that training of parents has no effect
  on offspring

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Non-inheritance

• Inheritance of learning could limit adaptability
• Advances/changes in ways of thinking
• e.g. sun revolves around the earth?
• Traditional male/female roles?

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Heredity and Learning Ability

• Dont inherit learned behaviours BUT
• Genetic influences on ability to learn
• Tryon (1940) rats learn maze, breed smartest
  together and dumbest together for 18
  generations
• Smart rats had smart rat pups
• Not inheriting a learned behaviour, but ability
  to learn quickly
• Identical twins reared apart
• Nature and nurture

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Neurological Damage

• Neurotoxins
• Prenatal damage to CNS (e.g., fetal alcohol
  syndrome, crack cocaine)
• Envrionmental toxins (e.g., lead)
• Physical damage (e.g., concussions)

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Critical Periods

• Stage for optimum learning
• Puppy dogs
• Konrad Lorenz Imprinting

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Harlow Harlow

• Monkeys terry cloth mothers
• Pit of despair
• Critical period for development of social skills

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Preparedness Learning

• Seligmans Continuum of Preparedness
• Prepared
• Unprepared
• Contraprepare

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Autoshaping

• Pigeons peck at key light CS even though
  unnecessary for arrival of US (food)
• Prepared for learning to peck key-light
• autoshaping

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Instinctive Drift

• Breland Breland (1961)
• miserly raccoon
• Contraprepared
• Innate tendencies (GBTs, FAPs) interfere with
  learning

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Biological Preparedness

• Remember bright-noisy water?
• Prepared for flavour taste aversion, unprepared
  for noise taste aversion

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Learning Evolution

• Like evolution, learning has no specific goal
• Not all learning is good
• Learned helplessness
• Vicarious learning of aggression
• Drug conditioning