The integration of the male-female set studied by simultaneous investigation of the instrumental sexual responses in rats.

Instrumental sexual responses were investigated under conditions that the contact between the subjects was possible when both of them had accomplished the instrumental response. The instrumental responses were studied in three situations: (i) when the female subjects were in induced estrus, (ii) when they were in natural estrus, and (iii) in natural diestrus. The correlation between the male and female response latencies was estimated for all sessions. The significant positive correlation was in about 40 percent of sessions in both estrus situations and only in 4 percent in the diestrus situation. The distribution of the correlation coefficients was similar in both estrus situations. In diestrus situation the positive correlation was less often observed then in estrus situations, yet it differed significantly from random distribution. It is concluded that the correlation between male and female response latencies could be used as an indicator of the degree of integration of the male-female set.