Functional Analysis of Masculine Copulatory Behavior in the Rat

The primary concern in this chapter is to describe how the elements of copulatory behavior are wired together, rather than how the nervous system controlling that behavior is wired together.

Abstract

This chapter describes the analysis the masculine copulatory behavior of the rat, and focuses over the behavioral elements, the temporal patterning of the elements, and the functional relations among the elements. Many measures of copulatory behavior, initiation latencies, copulatory rate, or number of intromissions, are found to vary rather independently of each other, and this evidence is taken as support for the view that sexual arousal is not unitary. The chapter explains how this functional analysis speaks to some of the models that have been developed. The data presented in the chapter explains that some or all of the arousal systems have inhibitory counterparts. This is particularly clear with respect to the absolute and relative post-ejaculatory refractory periods, but probably it is also true of systems controlling behavior prior to ejaculation. The evidence that the number of intromissions needed for ejaculation is substantially independent of the speed of this copulatory clock is also addressed. The chapter relates the behavioral analysis to a number of theoretical models of copulatory behavior. The primary concern in this chapter is to describe how the elements of copulatory behavior are wired together, rather than how the nervous system controlling that behavior is wired together. Nevertheless, behavioral and physiological analysis must proceed in parallel, and the consideration of the physiological evidence reminds us forcefully how little is known about the physiological mechanisms underlying sexual behavior.