THE IMPORTANCE OF TIME FOR THE INTROMISSION FREQUENCY IN THE MALE RAT MATING BEHAVIOUR

L arsson , K. The importance of time for the intromission frequency in the male rat mating behaviour. Scand. J. Psychol . 1961, 2 , 149–152.—A prolongation of the intervals separating the intromissions in the male rat mating pattern produces a decrease in the number of intromissions to ejaculate. By comparing the length of the interval effective in inducing a reduction of the response frequency in two groups of subjects, one composed of extremely 'slow' animals and another of extremely 'fast' ones, it was found that the appearance of the reduction effect was dependent on the length of the interco-pulatory interval characteristic of the individual. A reduction appeared in all animals when the interval of enforced rest was longer than the normal inter-copulatory interval.