Habituation of the Light-Startle Response of Orange Head Cockroaches (Eublaberus posticus): Effects of Acclimation, Stimulus Duration, Presence of Food, and Intertrial Interval

SIMPLE SUMMARY: This paper investigates habituation of the light-startle response (LSR) in orange head cockroaches (Eublaberus posticus) to improve our understanding of comparative insect psychology. Across four experiments, we found that cockroaches quickly learned to respond less to sudden changes in lighting. We also documented a number of findings common to habituation research, connecting our results to those of other popular model organisms. Our work lays a strong foundation for future research on the behavior of orange head cockroaches as well as learning in cockroaches in general. ABSTRACT: The purpose of this paper is to establish the orange head cockroach (Eublaberus posticus) as a useful insect subject for research in comparative psychology by investigating habituation of the light-startle response (LSR). While one goal of comparative psychology is to compare the behavior of a diversity of species, many taxa, including cockroaches, are grossly underrepresented. Our work serves to improve this deficit by investigating habituation learning in the orange head cockroach in four experiments. In our first experiment, we found that LSR, and habituation of LSR, occurs to both lights being turned on and lights being turned off. In our second experiment, we found that the duration of a light did not affect response, and that spontaneous recovery of LSR occurs after 24 h intervals. In our third experiment, we found that the presence of food inhibited LSR. In our final experiment, we found that the rate of LSR habituation decreased as intertrial interval increased, in a manner predicted by established principles of habituation. Our work lays a strong foundation for future research on the behavior of orange head cockroaches as well as learning in cockroaches in general. We hope that our findings help establish cockroaches as practical insect subjects for research in comparative psychology and related fields such as behavior analysis and behavioral ecology.