Motor programs for abdominal positioning in crayfish

Abstract

Using chronically implanted suction electrodes (Fig. 2), records were obtained from the tonic abdominal flexor motor neurons of crayfish while they were undergoing various self-generated movements (Fig. 3). The main behavior examined in this study was one of abdominal extension (Fig. 1), a response which could be evoked repeatedly. Other stereotyped movements were also observed. Each class of behavior we examined has been evoked previously in dissected preparations by stimulating command interneurons, allowing comparison of selfgenerated and electrically evoked motor patterns.