Activation and odor conditioning of suckling behavior in 3-day-old albino rats.

Investigated circumstances under which a novel odor could elicit nipple attachment behavior in 3-day-old Sprague-Dawley rats. In Exp I, Ss suckled washed nipples scented with citral (a lemon odor) only if they either had received tactile stimulation (by stroking with a soft brush) or had been administered amphetamine in the presence of citral prior to the suckling test. Ss stimulated in citral's absence or only exposed to citral without stimulation failed to suckle such nipples. In Exp II, Ss stimulated in a benzaldehyde (an almond odor) ambience suckled washed nipples scented with benzaldehyde but not those with citral scent. The opposite held for those stimulated in a citral-rich environment. The stimulus conditions that supported this conditioning were investigated in Exp III. Simultaneously increasing citral concentration and raising ambient temperature markedly attenuated the phenomenon. Exp IV demonstrated that not all classes of stimulation produced conditioning. Caffeine, in a wide range of doses, did not allow citral to elicit suckling on washed nipples. Findings are discussed within a framework of higher-order conditioning and may provide a mechanism by which naturally occurring stimuli come to elicit the species- and age-typical behavior of suckling. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)