Locust Wind Receptors

ABSTRACT The cervical connective of the desert locust contains interneurones giving responses of four different types to wind stimulation of the facial wind receptor setae. The four categories are : (a) ‘Wind-indicator cells’, giving a slowly adapting response to wind from any of a wide range of directions. (b) ‘Wind-direction cells’, displaying fairly slowly adapting responses, and sensitive to wind only within a very narrow range of directions. Pivoting wind into a cell’s optimal direction evokes a full response. (c) ‘Recentre cells’, showing rapidly adapting responses to wind onset from a fairly wide directional range. Rapidly shifting the wind direction from only one preferred side into the centre evokes a vigorous burst. (d) ‘Acceleration cells’, giving a rapidly adapting response which is especially pronounced for rapid wind accelerations. Interneurones connect with several sensory setae, whose spatial distribution and angles of curvature are unique to each interneurone type. A suggested integrative mechanism relates the angles of curvature of the input setae to the direction response of each interneurone type. The responses suggest roles for certain interneurone categories in flight maintenance and yaw-correcting reflexes.