Olfactory associative conditioning in infant rats with brain stimulation as reward: II. Norepinephrine mediates a specific component of the bulb response to reward.
One of the circuits modified by early olfactory learning is in the olfactory bulb. Specifically, response patterns of mitral-tufted cells are modified by associative conditioning during the early postnatal period. In addition, previous work has demonstrated that mitral-tufted cell single units respond to both olfactory conditioned stimuli and rewarding stimulation of the medial forebrain bundle-lateral hypothalamus (MFB-LH). The present study suggests that norepinephrine beta-receptor activation is required for early olfactory learning using MFB-LH stimulation as reward. Propranolol injected before odor-MFB-LH pairings blocks the acquisition of conditioned behavioral responses and their neural correlates to the conditioned odor. Furthermore, propranolol blocks a specific class of the mitral-tufted cell responses to MFB-LH reward stimulation. The relationship of this response to reward and early learning is discussed.
Wilson
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DA
Department of Psychology, University of Oklahoma, Norman 73019.
Sullivan
R M
RM
D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D003214:Conditioning, Classical / Q000502:physiology*; D004558:Electric Stimulation; D005260:Female; D007026:Hypothalamic Area, Lateral / Q000502:physiology; D008297:Male; D008474:Medial Forebrain Bundle / Q000502:physiology; D009042:Motivation; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D009638:Norepinephrine / Q000502:physiology; D009830:Olfactory Bulb / Q000502:physiology*; D009833:Olfactory Pathways / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012201:Reward; D012903:Smell / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology
D009638:Norepinephrine