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The Limitations of Learning
Limits
 Physical Characteristics
 Non-heritability
 Heredity of learning ability
 Neurological Damage
 Critical Periods
 Preparedness
 Instinctual Drift
 Biological Preparedness
 Sign Tracking
Physical Characteristics
 Physiological structure of the species
 Limitations on behaviours
 e.g. teaching chimps to
talk vs. teaching sign language
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
McDougall’s 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…
Agar (1954)
 Replicated McDougall’s 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
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?
Heredity and Learning Ability
 Don’t 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
Neurological Damage
 Neurotoxins
 Prenatal damage to CNS (e.g., fetal alcohol syndrome,
crack cocaine)
 Envrionmental toxins (e.g., lead)
 Physical damage (e.g., concussions)
Critical Periods
 Stage for optimum
learning
 Puppy dogs
 Konrad Lorenz &
Imprinting
Harlow & Harlow
 Monkeys & terry cloth
mothers
 “Pit of despair”
 Critical period for
development of social skills
Preparedness & Learning
 Seligman’s ‘Continuum of Preparedness
 Prepared
 Unprepared
 Contraprepare
Autoshaping
 Pigeons peck at key light CS even though unnecessary
for arrival of US (food)
 ‘Prepared’ for learning to peck key-light
 autoshaping
Instinctive Drift
 Breland & Breland
(1961)
 “miserly” raccoon
 Contraprepared
 Innate tendencies
(GBTs, FAPs) interfere
with learning
Biological Preparedness
 Remember ‘bright-noisy water’?
 Prepared for ‘flavour’ taste aversion, unprepared for
‘noise’ taste aversion
Learning & Evolution
 Like evolution, learning has no specific goal
 Not all learning is good
 Learned helplessness
 Vicarious learning of aggression
 Drug conditioning