Learning of leg position in the shore crab,carcinus maenas

Publisher Website
Google Scholar
Abstract
Decerebrate crabs were trained to raise their legs to avoid electric shocks. Compared with yoked controls, experimental crabs received significantly fewer shocks after 6-7 min training and also during the 1st minute of a subsequent testing period when experimental and control crabs were in a training situation. There was considerable variation in the performance of different crabs. Some learned quickly, some slowly; others did not learn at all. In some the raised leg position was maintained without further reinforcement. In others, periods when the animal was receiving few shocks were interrupted by periods when the leg was lowered and several shocks were received. A variety of leg movements were utilized by crabs to avoid shocks, the most common being flexion at the mero-carpopodite joint.