Visual and olfactory input segregation in the mushroom body calyces in a basal neopteran, the American cockroach.

摘要: The cockroach Periplaneta americana is an evolutionary basal neopteran insect, equipped with one of the largest and most elaborate mushroom bodies among insects. Using intracellular recording staining in protocerebrum, we discovered two new types neurons that receive direct input from optic lobe addition to neuron previously reported. These have dendritic processes lobe, projection sites tracts, send axonal terminals almost exclusively innermost layer MB calyces (input site MB). Their responses were excitatory visual but inhibitory olfactory stimuli, weak excitation occurred response mechanosensory stimuli cerci. In contrast, interneurons dendrites mainly antennal axon middle outer layers calyces. excited by various antenna. results suggest there general modality-specific terminal segregation this early event insect evolution. Possible postsynaptic presynaptic elements these are discussed.