title: Responses of the T-wave amplitude as a function of active and passive tasks and beta-adrenergic blockade.
abstract: This paper presents evidence that phasic changes in T-wave amplitude vary as a function of task conditions and beta-adrenergic drugs. Three experiments were designed to test the sensitivity of T-wave amplitude to manipulations in sympathetic arousal. In the first experiment, T-wave amplitude was recorded during an active behavioral task in which 32 subjects believed that they could control the duration of an aversive white noise and during a passive behavioral task in which another 30 subjects knew that they had no control. T-wave amplitude decreased to a greater extent in the active behavior group than in the passive group. In the second experiment, 9 subjects receiving one of two beta-adrenergic blockers and 10 subjects receiving placebo completed the active task. Task-induced reductions in T-wave amplitude were systematically blocked by the beta blockers. In the third experiment, 5 subjects received placebos and 15 received one of two different beta blockers. All subjects performed a mental arithmetic task. Subjects receiving a placebo, but not those receiving beta blockade, exhibited a significant reduction in T-wave amplitude during mental arithmetic.
authors.affiliation: Eberhard-Karls University of Tübingen, Clinical and Physiological Psychology Division, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Rau
mesh_terms: D000223:Adaptation, Psychological / Q000187:drug effects*; D000328:Adult; D000526:Alprenolol / Q000494:pharmacology*; D001143:Arousal / Q000187:drug effects*; D004311:Double-Blind Method; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006321:Heart / Q000294:innervation*; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000494:pharmacology*; D008875:Middle Aged; D011597:Psychomotor Performance / Q000187:drug effects*; D013564:Sympathetic Nervous System / Q000187:drug effects*
chemical_list: D000526:Alprenolol; D008790:Metoprolol