Avoidance and escape components of leg position learning in the prothoracic and mesothoracic ganglia of the cockroach, P. americana.

Prothoracic and mesothoracic legs of headless cockroaches with only a ventral nerve cord were trained to lift their legs when shock occurred. The prothoracic leg showed both avoidance learning (a decrease over time in the frequency of leg extension) and escape learning (a decrease in extension duration following shock receipt). The mesothoracic leg showed avoidance learning as fast and as well as the prothoracic leg but was unable to support escape learning. Furthermore, the avoidance component of prothoracic learning showed longer-term retention of several hours whereas the escape component showed only shorter-term retention which did not last 15 minutes.