Multi?directional sensitivity of statocyst receptor cells of the opisthobranch gastropod Aplysia limacina

Abstract

The electrical activity in the static nerves of Aplysia limacina was studied in relation to the spatial orientation of the animal. Each sense cell shows a multi‐directional sensitivity. Hence, it responds during full‐circle rotations about all horizontal axes but only within a limited angular range. The statocyst receptor cells are found to be gravity receptors only, and their electrical behaviour suggests that main information about the spatial orientation of Aplysia is contained in the pattern of responding cells, i.e. which of the 13 cells are active at any one time, and not in their absolute discharge frequencies. Furthermore, evidence is given to a similar function of the statocysts of opisthobranch and pulmonate gastropods.