title: Infantile handling and sex as determinants of the negative reinforcing effects of gentling.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001362:Avoidance Learning; D005260:Female; D006234:Handling, Psychological; D008297:Male; D051381:Rats; D012054:Reinforcement, Psychology; D012737:Sex Factors; D014796:Visual Perception