Hypothalamic and Olfactory Control of Sexual Behavior and Partner Preference in Male Rats

• Published in: Physiology & behavior Vol. 60; no. 5; pp. 1347 - 1354
• Main Authors: EDWARDS, DAVID A, WALTER, BEN, LIANG, PAUL
• Format: Journal Article
• Language: English
• Published: Cambridge Elsevier Inc 01.11.1996; New York, NY Elsevier
• Subjects: Anatomical correlates of behavior; Animals; Behavioral psychophysiology; Biological and medical sciences; Brain lesions; Copulation - physiology; Denervation; Female; Fundamental and applied biological sciences. Psychology; Hypothalamus - physiology; Hypothalamus, Anterior - physiology; Male; Olfaction; Olfactory Bulb - physiology; Preoptic Area - physiology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rats; Sexual behavior; Sexual Behavior, Animal - physiology; Sexual motivation; Smell - physiology; Rats; Sexual motivation; Brain lesions; Olfaction; Sexual behavior; Affect affectivity; Rat; Rodentia; Central nervous system; Male; Mate selection; Hypothalamus; Breeding behavior; Reproduction; Vertebrata; Mammalia; Olfactory pathway; Motivation; Animal; Perception; Olfactory bulb; Lesion; Brain (vertebrata)
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/S0031-9384(96)00260-0

Sexually active male rats prefer a sexually receptive female to a nonreceptive female, and partner-preference tests provide one way of studying sexual motivation. Surgical deafferentation of the olfactory bulbs from all the known chemosensory systems of the nasal septum renders rats anosmic. In Experiment 1, we show that, although bulb deafferentation of male rats decreases some aspects of sexual performance, most deafferented males copulate and partner preference is not affected. In Experiment 2, we show that large excitotoxin lesions of the preoptic hypothalamus eliminate copulation, an effect that is correlated with damage to the anterior portions of the medial and lateral preoptic area. Lesions also decrease partner preference, an effect that is correlated (r = 0.82) with damage to a small part of the bed nucleus of the stria terminalis. Most males who do not copulate after hypothalamic lesions show a persistent, albeit reduced, preference for receptive females over nonreceptive females. This preference appears to depend on olfactory ability because bulb deafferentation of lesioned, noncopulating males virtually eliminates partner preference.