ANIMAL LEARNING

Prof. S. D. RathodB N Bandodkar College of Science

Thane, Maharashtra, India

Pavlov’s Classical Conditioning

Conditioning involves Ivan Pavlov

UCS = unconditioned stimulus

UCR = unconditioned response

CS = conditioned stimulus

CR = conditioned repose

UCS (food) UCR (salivation)

UCS (food)+ CS (bell) UCR (salivation)

CS (bell) CR (salivation)

Classical ConditioningPavlov’s experiment

The unconditioned stimulus (UCS) is one that naturally evokes the unconditioned response (UCR). After pairing the CS with the UCS repeatedly, the CS alone will come to evoke the response, which is now known as the conditioned response (CR).

Acquisition Acquisition refers to the first stages of

learning when a response is established.

In classical conditioning, repeated pairings of the conditioned stimulus (CS) and the unconditioned stimulus (UCS) eventually leads to acquisition.

Acquisition

Extinction

 Extinction is when the occurrences of a conditioned response decrease or disappear. In classical conditioning, this happens when a conditioned stimulus is no longer paired with an unconditioned stimulus.

Habituation

Decrease in the strength of a response after repeated presentation of a discreet stimulus

Getting used to it, sort of

Goose-Hawk Silhouette

Generalization

Stimulus Generalization is the tendency for the conditioned stimulus to evoke similar responses after the response has been conditioned.

If animal is some when alarmed by red color signal then animal will fear with all red color signals.

Friendly environment for Rabbit

Dangerous environ’t. for Rabbit

Instrumental Learning

Instrumental learning is another term for operant conditioning, a learning process first described by B. F. Skinner.

Through operant conditioning, an association is made between a behavior and a consequence for that behavior.

Thorndike’s law of effect

In instrumental conditioning, reinforcement or punishment are used to either increase or decrease the probability that a behavior will occur again in the future.

Neutral operants: responses from the environment that neither increase nor decrease the probability of a behaviour being repeated.

Reinforcement

Reinforcers: Responses from the environment that increase the probability of a behaviour being repeated. Reinforcers can be either positive or negative.

Positive Reinforcement

A particular behavior is strengthened by the consequence of experiencing a positive condition.

For example: A hungry rat presses a bar in its cage and receives food. The food is a positive condition for the hungry rat. The rat presses the bar again, and again receives food. The rat's behavior of pressing the bar is strengthened by the consequence of receiving food.

Negative Reinforcement

A particular behavior is strengthened by the consequence of stopping or avoiding a negative condition.

For example: A rat is placed in a cage and immediately receives a mild electrical shock on its feet. The shock is a negative condition for the rat. The rat presses a bar and the shock stops. The rat receives another shock, presses the bar again, and again the shock stops. The rat's behavior of pressing the bar is strengthened by the consequence of stopping the shock.

Punishment

Punishers: Response from the environment that decrease the likelihood of a behaviour being repeated. Punishment weakens behavior.

For example: A rat presses a bar in its cage and receives a mild electrical shock on its feet. The shock is a negative condition for the rat. The rat presses the bar again and again receives a shock. The rat's behavior of pressing the bar is weakened by the consequence of receiving a shock.

Operant Behavior

B F Skinner

Operant Behaviour Skinner used the term operant to

refer to any "active behavior that operates upon the environment to generate consequences" (1953). 

Operant behaviour, on the other hand, involves the organism actively performing (operating) in the environment without responding to a particular stimulus.But his work was based on Thorndike’s law of effect

Skinner’s Experiment

Operant conditioning

Fixed ratio schedule (repeatations are fixed)

Variable ratio schedule Fixed interval schedule Variable interval schedule

Thank You