Transcript Nim did apply some of the signs in a new context

Observational Learning, Language
and Rule-Governed Behavior
Chapter 12
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Steven I. Dworkin, Ph.D.
Bandura and Walters
• Social learning theory
– Classical and operant conditioning
– Observational learning (imitation)
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Steven I. Dworkin, Ph.D.
Observational Learning
• In Classical Conditioning
– Conditioning of vicarious emotional responses
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Steven I. Dworkin, Ph.D.
Observational Learning
• In Operant Conditioning
– Acquisition
• Pay attention to behavior of model
– Sensitivity to consequences of model’s behavior
– Explicit reinforcement for attending to model
» Prompting
» Physical modeling
» Reinforcement
– Observer can understand and duplicate
– Personal characteristics of model
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Steven I. Dworkin, Ph.D.
Observational Learning
• In Operant Conditioning
– Performance
• Attend to model
• Reinforcement or punishment of model’s behavior
• Reinforcement history
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Steven I. Dworkin, Ph.D.
Bandura and the Bobos
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Steven I. Dworkin, Ph.D.
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Steven I. Dworkin, Ph.D.
Bandura, Ross & Ross (1961)
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Steven I. Dworkin, Ph.D.
Thorpe’s Categories
• Social facilitation
– One’s behavior prompts similar behavior of another
• Local enhancement
– Behavior directs attention to object
• True imitation
– Imitation of a novel behavior pattern in order to achieve
a specific goal of particular interest is very unusual or
improbable behaviors.
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Steven I. Dworkin, Ph.D.
Theories of Imitation
• Imitation as an instinct
– Infant tongue protrusion
– Reaction to fear in others
• Imitation as an operant response
– Discriminative stimulus is behavior of another
individual
• Imitation as a generalized operant response
– History of reinforcement
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Steven I. Dworkin, Ph.D.
Bandura’s Theory
• Bobo doll studies
– Reinforcement not necessary for learning by observation
– Expectation of reinforcement is necessary for performance of
behaviors acquired from observational learning
• Factors responsible for imitation
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Attentional Processes
Retentional Processes
Motor reproductive processes
Incentive motivational processes (behavior will result in
reinforcers)
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Steven I. Dworkin, Ph.D.
Factors Affecting Likelihood of
Imitation
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Rewardingness of model
Powerful figures
Similarity (sex, age, interests)
Sincerity
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Steven I. Dworkin, Ph.D.
Interactions Between Observational
Learning and Operant Conditioning
• Achievement motivation (delay of
gratification, self-control)
• Aggression (the apparent paradox)
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Steven I. Dworkin, Ph.D.
Influence of Media
• Correlational data – positive relationship
watching TV and aggression.
• Longitudinal study – watching violent TV
can lead to aggression.
• Controlled experiments – increased
aggression
• Field experiments – modest effect
• Meta Analysis- Positive relationship.
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Steven I. Dworkin, Ph.D.
What Can Be Learned
Through Observation
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Industriousness
Phobias
Drug Use and addictions
Cognitive development
– Concept formation
• Morals
– Suicide and soap operas
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Steven I. Dworkin, Ph.D.
Modeling in
Behavioral Therapy
• Facilitation of low-probability behaviors
– Graduated modeling
– Assertiveness training
• Acquisition of new behaviors
• Elimination of fears and unwanted
behaviors
• Videotape self-modeling
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Steven I. Dworkin, Ph.D.
What is Language?
• Body Language?
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Steven I. Dworkin, Ph.D.
Language
• Characteristics of true language
• Abstract/Arbitrary symbols
• Displacement: ability to communicate about things
not physically present
• Prediction: ability to communicate about things
that haven’t happened yet
• Interrogation: ability to ask questions
• Creativity
• Syntax
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Steven I. Dworkin, Ph.D.
Language
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Reference – use of arbitrary symbols
Grammar – set of rules control meaning of words
Productivity – infinite number of expressions
Situational freedom – used in a variety of contexts
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Washoe
•
In 1966 Beatrice and Allen Gardner began teaching a
chimpanzee called Washoe the use of American Sign Language
(ASL or AMESLAN), a gestural form of communication used
by deaf people. Avoiding the use of vocal communication they
were overcoming the problem of speech production in apes. All
the humans interacting with Washoe used sign language
exclusively in her presence. Washoe was and is able to use
learned signs in a wide variety of contexts: "open“ for example
would be used with doors, tins and nuts. Washoe adopted an
infant chimpanzee called Loulis in whose presence no human
would use any signs. Despite this he had a repertoire of about
50 signs after five years, learned by imitation and instrumental
conditioning of Washoe and other signing apes in the research
centre. Washoe is reported to have invented "new" words: once
she was signing "Water" - "Bird" when she saw a swan for the
first time. She now lives at the Chimpanzee and Human
Communication Institute at the Central Washington University
together with a group of other chimpanzees.
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Sarah
• Sarah, another chimpanzee was taught by David Premack to use colored
plastic tokens that could be attached to a magnetized board. The tokens varied
in shape, color, size and texture. For example the symbol for an apple is a
light-blue plastic triangle. The top sentence would read: Apple is red. As you
can see the symbols are not at all related to the word they stand for.
• Sarah was also taught to interpret conditional sentences like the following: "If
Sarah takes the banana, Mary will not give chocolate to Sarah". The ape
managed to act according to the meaning of the sentence and even to apply the
use of IF and IF-NOT to new situations.
• The vocabulary of Sarah consisted of about 130 signs and constructions like
Yes-No questions, "Name of" procedures, properties and classes (large-small,
color...), concepts, quantifiers, "this" and "that" and "same".
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Steven I. Dworkin, Ph.D.
Lana
• The Lana Project (or LANguage
Analog) established in 1971.
• Lana, a chimpanzee, was trained by
Duane Rumbaugh to use a keyboard
with abstract symbols. Lana also
created new words and used known
symbols in a new context. She lives
at the Language Research Centre in
Atlanta, Georgia where other
chimpanzees (Sherman and Austin)
and booboos (Kanzi and
Panbanisha) are also successfully
trained with the same method.
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Steven I. Dworkin, Ph.D.
•
Herbert S. Terrace was skeptical of the so-called
language-use by Washoe, Sarah and Lana. He
compared the abilities of the apes with those
found in pigeons which are taught to peck keys in
a specific order. All apes signed only to receive
reward from their trainers. If you have a look at
the first and mostly used words of the animals in
the projects you will find that they are almost all
related to food, drink and other desirable
activities like tickling and chasing. Therefore
Terrace raised and trained Nim Chimpsky
(named after the famous linguistic theorist Noam
Chomsky who stated that the predisposition for
language acquisition is innate). The method was
the same used with Washoe and Nim learned
about 125 signs. He demonstrated some syntax by
using the verb more frequently before the object
than vice versa (e.g. "hug Nim" instead of "Nim
hug"). Nim did apply some of the signs in a new
context (e.g. DIRTY when he had to go to the
toilet). He also warned people by using the signs
for ANGRY and BITE and tended not to attack if
this warning was heeded. But by analyzing the
videos of the training sessions Terrace found that
Nim's signs often were imitations of the signs the
trainer first used. Terrace et al. (1979) concluded
that there was little evidence that Nim was
actually using language. They also found out by
analyzing Washoe's videos that she mimicked the
trainer like Nim did.
Nim
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Steven I. Dworkin, Ph.D.
Tentative Conclusions
• Animals have some measure of linguistic
ability
– Use words, signs or symbols to represent
objects, actions and descriptions.
– More recent research non-humans can learn
some basic principals of language.
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Rule Governed Versus
Contingency Shaped Behavior
• Rule – verbal description of a contingency
• Rule-governed behavior – behavior
generated through exposure to rules
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Steven I. Dworkin, Ph.D.
Rule Governed Versus
Contingency Shaped Behavior
• Advantages
• Disadvantages
– Less efficient
– Insensitive to actual contingencies
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Steven I. Dworkin, Ph.D.