Download Operant Conditioning

Operant Conditioning
Burrhus Frederic Skinner (1904-90) developed the behaviourist approach
called radical behaviourism. This states that psychologists should only use
scientific methods to investigate animal and human behaviour.
Operant Conditioning: All behaviour is learned from consequences of
behaviour.
The consequences of behaviour are seen as either rewarding or punishing.
Behaviours that receive a reward are more likely to be repeated on similar
occasions in the future. Behaviours that receive punishment are less likely to
be repeated in the future and maybe extinguished entirely.
Skinner conducted most of his experiments on animals such as Rats or
Pigeons. He used a device called the Skinner Box. In this box a hungry rat
has to learn to press a lever to obtain the reward of food. Since pressing a
lever is not a normal part of a rat’s behaviour it has to learn this operation.
Only if the rat presses the lever does it get the reward of food. If the rat is
reinforced every time it presses the lever (continuous reinforcement), the
behaviour of lever-pressing is learned, or becomes ‘stamped in’.
Process of Operant Conditioning
Rat approaches
the lever in the
Skinner box.
Psychologist
rewards the rat
by dispensing a
pellet of food.
Rat presses lever
and a pellet of
food (reward) is
automatically
dispensed
Rat continues to
press the lever to
get food
(reward). Rat has
learnt a new
behaviour
Stimulus of
hunger and
response of
pressing the
lever is rewarded
with the food
Note that the rat is first rewarded for approaching the lever. This is
because the normal behaviour of a rat does not involve pressing levers.
Pressing the lever has to be learned as a new behaviour.
Differences in Operant Conditioning
In 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.
In 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.
In Punishment a particular behavior is weakened by the consequence of
experiencing a negative condition.
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.
In Extinction a particular behavior is weakened by the consequence of not
experiencing a positive condition or stopping a negative condition.
For example: A rat presses a bar in its cage and nothing happens. Neither a
positive nor a negative condition exists for the rat. The rat presses the bar
again and again nothing happens. The rat's behavior of pressing the bar is
weakened by the consequence of not experiencing anything positive or
stopping anything negative.