| Abstract: | Age and sex differences in behaviors mediated by the ventromedial hypothalamus (VMH) were examined in the rat. Circadian rhythm, emotionality, and taste responsiveness (except for responsiveness to quinine adulteration) were found to shift, in one or both sexes, toward a pattern suggesting decreased VMH functioning with increasing age. A post hoc analysis of the configuration of positive and negative results suggests that, for those behaviors known to show both immediate and sustained effects of VMH lesion, male rats show a marked trend toward the lesioned pattern of behavior with increasing age, whereas females show weaker or nonexistent age trends in the same behaviors. For those behaviors that have been shown to change only during the static, obese phase, or for which data re controversial as to whether changes take place as a result of the VMH lesion at all, this age and sex pattern does not emerge. |
