Studying temporal properties of stimulus-evoked responses in the ventral nerve cord of insects.

Students in undergraduate laboratory settings learn many of the foundational principles of sensory processing in the comparatively simple, easy to study invertebrate nervous system. In this example preparation, the American cockroach, students record action potentials from the fibers in the ventral nerve cord (VNC) that participate in a well explained escape behavior in response to stimulation of its cerci, a pair of mechanosensitive abdominal appendages. A system that allows good control over the time and amplitude of the air pulse delivered to the cerci is described. This experimental setup enables students to extract and display temporal information from recordings to learn how to interpret those responses in the context of the properties of the stimulus. I offer examples of specific investigations and analyses that work well for this purpose in an undergraduate laboratory.