title: Autonomic nervous control of heart rate orienting and alpha responses in dog.
abstract: The object of this experiment is to study the autonomic nervous control of alpha responses elicited in classical conditioning. Twenty-two mongrel dogs were trained in classical discriminative conditioning. Typical two-phase tachycardic responses were observed in positive (CS+) trials while only the earliest, phase 1, response was observed in negative (CS-) trials. The phase 1 response, which was identical in CS+ and CS-trials, was compared in dogs before and after selective SA-nodal parasympathectomy (N = 7) and beta-adrenergic blockade (N = 11). The phase 1 tachycardic response was eliminated by selective SA-nodal parasympathectomy but not by beta-adrenergic blockade. We conclude that the phase 1 response observed in both CS+ and CS-trials with similar time sequence and magnitude is an alpha response. The heart rate orienting response results from a withdrawal of parasympathetic activity with little or no change in sympathetic tone.
authors.affiliation: Department of Physiology, University of Kentucky, College of Medicine, Lexington 40536-0084, USA.
authors.forename: S
authors.initials: S
authors.lastname: Li
authors.forename: D C
authors.initials: DC
authors.lastname: Randall
authors.forename: D R
authors.initials: DR
authors.lastname: Brown
authors.forename: M E
authors.initials: ME
authors.lastname: Olmstead
authors.forename: J M
authors.initials: JM
authors.lastname: Kilgore
authors.forename: M G
authors.initials: MG
authors.lastname: White
mesh_terms: D000818:Animals; D001143:Arousal / Q000502:physiology*; D001341:Autonomic Nervous System / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology; D004285:Dogs; D006339:Heart Rate / Q000502:physiology*; D009949:Orientation / Q000502:physiology*; D010275:Parasympathetic Nervous System / Q000502:physiology; D011943:Receptors, Adrenergic, beta / Q000502:physiology; D012849:Sinoatrial Node / Q000502:physiology; D013564:Sympathetic Nervous System / Q000502:physiology
chemical_list: D011943:Receptors, Adrenergic, beta