In this task, animals are placed in a two-compartment shuttle box and have to learn the association between a conditioned stimulus (CS, e.g. light) and an unconditioned stimulus (US, e.g. footshock).
- Conditioned response/Avoidance
Subjects give a conditioned response when they avoid receiving the shock, by moving to the opposite compartment during the CS presentation (avoidance response).
- Unconditioned response/Escape
If animals do not act, footshock is delivered, but can be escaped by moving to the opposite compartment (escape response).
This test is also used for assessing depressive-like symptoms in animals involved in a “learned helplessness procedure”. In this context, the use of a previous inescapable shock session has profound and long-lasting disruptive effects on the ability of the animals to learn to escape shocks. This escape deficit can be prevented by administering antidepressants.