1. Lesson 11: One
Trial Learning
and Trial and
Error Learning

2. From last lesson......
What role does the learner play in each of the different
types of conditioning?

3. From last lesson......
What role does the learner play in each of the different
types of conditioning?
In classical conditioning, the learner is passive, whereas in operant
conditioning the learner actively chooses to respond in a particula
manner to gain reinforcement or avoid punishment

4. This lesson........
• Explain and apply one-trial learning with reference to taste aversion as informed
by John Garcia and Robert A.Koelling (1966)
• Explain and apply trial-and-error learning as informed by Edward Lee Thorndike’s
puzzle-box experiment

5. Trial and error learning involves learning by trying
alternative possibilities until the desired outcome is achieved

6. Trial and error learning involves learning by trying
alternative possibilities until the desired outcome is achieved
A simple way of learning to cope with the environmental demands

7. Trial and error learning involves learning by trying
alternative possibilities until the desired outcome is achieved
A simple way of learning to cope with the environmental demands
Required that an individual (or animal) be motivated to
explore and respond to the environment

8. Trial and error learning involves learning by trying
alternative possibilities until the desired outcome is achieved
A simple way of learning to cope with the environmental demands
Required that an individual (or animal) be motivated to
explore and respond to the environment
Correct Responses (trials) must be rewarded

9. Thorndike’s puzzle box experiment demonstrated trial
and error in cats
A hungry cat is placed in a
box with slatted sides, food is
placed outside the box and
can be seen
Cat must
operate a
lever to open Cat initially explores box and
the door and unsuccessfully tries to escape
escape to get
the food
By accident (during trial and
error) the cat presses the
lever that opens the door
Cat escapes and eats the food (i.e. is rewarded)
Escape times become faster as the number of trails increase

11. Cat is ‘instrumental’ in learning the correct response
and ‘operated’ on the environment to get the desired
outcome. Thorndike called this ‘instrumental
learning’
The results of this experiment led Thorndike to develop the
law of effect.
The law of effect essentially states that a behaviour that is
accompanied or closely followed by ‘satisfying‘ consequences is
more likely to recur, and a behaviour that is followed by ‘annoying‘
consequences or discomfort is less likely to recur.

12. One-Trial Learning
Have you ever been nauseated after once eating a particular
food and never eaten that same type of food again

13. One-Trial Learning
Have you ever been nauseated after once eating a particular
food and never eaten that same type of food again
One-trial learning (OTL): a relatively permanent change
in behaviour as a result of one experience only.

14. One-Trial Learning
Have you ever been nauseated after once eating a particular
food and never eaten that same type of food again
One-trial learning (OTL): a relatively permanent change
in behaviour as a result of one experience only.
Taste aversion: a conditioned response involving
avoidance of food associated with feeling/being ill when eaten
previously

15. One-trail learning is not
Classical Conditioning because:
One Trial Learning involves one pairing of CS (tasting/eating food)
and UCS (illness), not numerous trials as per CC
In One Trial Learning, time lapse between CS and UCS can be
up to 12 hours or more, but in CC the CS and UCS occur close
together.

16. Research by Garcia and Koelling (1996)
Garcia and Koelling (1966) showed that rats soon learned to avoid a sweet-
tasting liquid when it was followed by an injection that made them ill, but
they did not learn to avoid the liquid when they received electric shocks
afterwards.
Presumably this is connected with learning what foods they could safely
eat. The rats did, however, learn to avoid the electric shock when it was
paired with light and noise (but injection+light/noise failed). Maybe this
is related to learning about natural hazards like lightning or falling
objects.