Burrhus Frederick Skinner was an influential American psychologist known for his work on operant conditioning from the 1930s-1960s. He developed operant conditioning through his work using animal subjects like pigeons and rats in what was known as a Skinner box. Skinner believed that behavior is shaped by reinforcement or reward rather than free will. Operant conditioning posits that learning is the result of changes in overt behavior due to responses to environmental stimuli. When a stimulus-response pattern is reinforced through reward, the individual learns to repeat that response. Reinforcers can be positive, like a reward added, or negative, like removing an unpleasant stimulus. Behavior is shaped through successive approximations using reinforcement.

1. Behaviorist Perspective

2. Burrhus Frederick
Skinner
(1904-1990)

3. Burrhus Frederick Skinner
• American psychologist - influential from the
1930’s - 60’s – developed operant
conditioning
• Skinner was interested in education
– He believed that behavior is sustained by
reinforcements or rewards, not by free will.
• Famous for the skinner box & the teaching
machine
• Often worked with pigeons & rats and applied
what he learned with these animals to human
learning

4. Operant Conditioning
• Is based upon the notion that learning is a
result of change in overt behavior.
• Changes in behavior are the result of an
individual’s response to events (stimuli) that
occur in the environment.
S R
Stimuli-response (S-R) pattern is reinforced
(rewarded), the individual is conditioned to respond

5. Reinforcement
• Positive Reinforcer – is any stimulus that is
given or added to increase the response.
• Negative Reinforcer – is any stimulus that
results in the increased frequency of a
response when it is withdrwan or
removed.

6. Non-reinforcement
• Shaping of Behavior- An animal on a cage may
take a very long time to figure out that pressing
a lever will produce food. To accomplish such
behavior successive approximations of the
behavior are rewarded until the animal learns
the association between the lever and the food
reward. To begin shaping, the animal may be
rewarded for simply turning in the direction of
the lever, then for moving toward the lever for
brushing against the lever, and finally for
pressing the lever.

9. • Behaviorist Chaining – come about when a
series of steps are needed to be learned. The
animal would master each step in sequence
until the entire sequence is learned.
• Reinforcement Schedules - once the desired
behavioral response is accomplished,
reinforcement does not have to be 100% in
fact it can be maintained more successfully
through what skinner reffered to as partial
reinforcement schedules. Partial
reinforcement schedules include interval
schedules and ratio schedules.

11.  Fixed Interval Schedules the target
response is reinforced after a fixed
amount of time has passed since the last
reinforcement.
Variable Interval Schedules – the amount
of time that must pass between
reinforcement varies.
Fixed Ratio schedules- a fixed number of
correct responses must occur before
reinforcement may recur.

12. The End