MICROCIRCUITRY OF THE MORMYRID ELECTROSENSORY LATERAL-LINE LOBE

The mormyrid electrosensory lateral line lobe (ELL) is a laminated str ucture in the dorsal rhombencephalon receiving topographically ordered primary sensory input from electroreceptors and corollary signals fro m the electromotor command nucleus. The structural basis of the integr ation of these and other inputs was investigated at the light and elec tron microscopical level using neuroanatomical tracers, immunohistoche mistry and Golgi-impregnations. The ELL contains at least 14 distinct cell types. These include small granule cells receiving primary affere nt input, GABA-ergic spiny interneurons and glutamatergic projection n eurons integrating sensory input and descending feedback, and deep int razonal neurons. Present knowledge of the synaptic organization of the ELL afferents and cell types allows for a preliminary scheme of its m icrocircuitry.