ABSTRACT
Visual stimuli presented to a locust during performance of a defensive kick fail to elicit a response from the descending contralateral movement detector (DCMD) visual interneurone. Similar control stimuli presented before the initial flexion and at least 1 s after the movement elicit a normal DCMD response (10–15 spikes).
External stimuli used to elicit defensive kicking can sometimes cause suppression of the DCMD without the occurrence of kicking, but only when there is an increase in central nervous activity, or associated behavioural response.
Proprioceptive stimulation similar to that occurring in a kick does not cause suppression of the DCMD unless there is an increase in central nervous activity or associated behavioural response.
Extensive dorsal dissection abolishes the suppression of the DCMD.
