For most animals, food is their primary reinforcement,
2.
In secondary reinforcement, a response is strengthened by the use of a stimulus associated with a different stimulus of primary reinforcement value.
3.
"' Information hypothesis of conditioned reinforcement "'( Berlyne, 1960; Bloomfield, 1972, Rachlin, 1976 ) states that the conditioned reinforcing strength of a stimulus is a function of its informativeness about the availability of primary reinforcement.
4.
This task is aided by the orbitofrontal complex . " In terms of learning theory, the amygdala appears to handle the presentation of primary reinforcement, while the orbitofrontal cortex is involved in the detection of omission of reinforcement ."