Page 37 - Zoo Animal Learning and Training

1.4 Operant Conditioning 9

VetBooks.ir something the organism tries to avoid or analysis is the parent’s? What procedure is
being used if their behaviour of giving the
escape, such as electric shock from an electric
fence. For example, when you want a horse to
one isn’t easy, but you already know every­
turn left, pressure is applied to the left rein. child candy for decreasing the tantrum? This
The horse, to avoid the pressure of the bit, thing you need to answer this question cor­
will turn its head left and the behaviour is rectly. The parent did not like the tantrum
likely to increase. A horse that is used to being and the embarrassing situation it was creat­
ridden will take the slightest cue of the reins ing. This aversive situation was presented
to avoid any pressure. Negative reinforce­ before the parent allowed the child to have
ment confuses a lot of people, so let’s look at a the candy. After the parent gave the child the
second example. A person with a headache candy, the child stopped tantruming and
may take an aspirin. If the headache goes the aversive situation was gone. Therefore, the
away, the person is likely to take an aspirin the parent’s behaviour was negatively reinforced.
next time a headache occurs. The response
(taking aspirin) results in the removal of an 1.4.2 Schedules of Reinforcement
event (headache) and the response rate
increases (taking aspirin increases). Inarguably, Skinner’s most influential contri­
In positive punishment, a stimulus is added, bution to the science of behaviour is his 1957
but the rate of the behaviour decreases over publication on schedules of reinforcement
time. For example, when someone puts a with his colleague Charles Ferster. However,
shock collar on a dog to stop the dog from this idea wasn’t created by formal empirical
barking, they are adding a stimulus (shock) in methods or theoretical questioning. The idea
hopes of decreasing a behaviour (barking). If was serendipitous, caused by necessity to
the dog does decrease its rate of barking in the have some time off and lack of resources. In
future, then positive punishment was used. explaining the origins of the schedules of
The last basic procedure is negative punish- reinforcement theory, Skinner wrote:
ment. In this procedure, the removal of a stim­
ulus decreases the target behaviour. For Eight rats eating a hundred pellets each
example, you might remove your attention by day could easily keep up with production.
walking away or turning your back to an ani­ One pleasant Saturday afternoon I sur­
mal during a training session if they did some­ veyed my supply of dry pellets, and,
thing incorrect (i.e. a timeout). If the rate of appealing to certain elemental theorems in
that incorrect behaviour decreases in the arithmetic, deduced that unless I spent the
future, then negative punishment was used. rest of that afternoon and evening at the
To assess which of these four basic proce­ pill machine, the supply would be
dures is being used, you must know what exhausted by ten‐thirty Monday morning
behaviour you are analysing. For example, a …. It led me to apply our second principle
parent and a child are in a grocery store. As of unformalized scientific method and to
they pass the candy aisle, the child grabs a bag ask myself why every press of the lever had
of candy. The parent, noticing this behavior, to be reinforced. (Skinner 1956, p. 226)
asks the child to put the candy back on the
shelf. Immediately, the child has a tantrum in Skinner’s data showed interesting patterns
the store yelling that they want the candy. The of behaviour when the pellets were provided
parent, embarrassed by the child’s behavior, at different intervals and decided that ‘when
gives the child the candy back. If the rate of you run into something interesting, drop
tantrums increase in the future when the everything else and study it’ (Skinner 1956,
child wants something, which procedure was p. 363). Schedules of reinforcement were
used? If you said positive reinforcement, you born that day.
are correct. But what if the behaviour under But what are schedules of reinforcement?