Abstract: Spatial localization of EPSP evoked by stimulation of the alfactory nerve on the soma,lateral and ventral dendrites of the crucian carp Mauthner cell was explored by means of multiple intracellular recording technique. The maximum amplitude of the first component of the olfactory EPSP was recorded at the regions near the soma. It declined progressively along the lateral and ventral dendrites. The second component presented the largest amplitude at the most distal segment of the ventral dendrite and became smaller and smaller while the recording electrode was moved gradually towards the soma and the lateral dendrite. It is suggested that the olfactory inputs concentrate and impinge on the sites near the soma and on the most distal ventral dendrite at least more than 600μm from the soma respectively.

Key words: olfactory nerve, EPSP, Mauthner cell, crucian carp