An antennal-derived mechanosensory pathway in the cockroach: descending interneurons as a substrate for evasive behavior.

Large amplitude units responding to intense winds or touch of the antennae were recorded extracellularly from the cervical connectives of the cockroach, Periplaneta americana. Intracellular recording and staining revealed a number of interneurons with cell bodies in one of the head ganglia and large caliber axons descending to thoracic levels. These cells respond to touch of an antenna at very short latencies. The properties of these cells suggest that in the cockroach they may be a substrate for non-GI evasive behavior, especially for responses to predators which are detected by tactile cues.