Neural and cardiovascular responses to emotional stress in humans

• Published in: American journal of physiology. Regulatory, integrative and comparative physiology Vol. 295; no. 6; pp. R1898 - R1903
• Main Authors: Carter, Jason R, Durocher, John J, Kern, Rosalie P
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 01.12.2008
• Subjects: Blood Pressure; Cardiovascular System - innervation; Emotions; Heart Rate; Humans; Male; Muscle, Skeletal - innervation; Neurohumoral Control of Cardiovascular Function; Neurons; Random Allocation; Stress; Stress, Psychological - physiopathology; Studies; Sympathetic Nervous System - physiopathology; Visual Perception; Young Adult
• ISSN: 0363-6119; 1522-1490
• DOI: 10.1152/ajpregu.90646.2008

1 Department of Exercise Science, Health, and Physical Education, and 2 Department of Cognitive and Learning Sciences, Michigan Technological University, Houghton, Michigan Submitted 30 July 2008 ; accepted in final form 3 September 2008 Sympathetic neural responses to mental stress are well documented but controversial, whereas sympathetic neural responses to emotional stress are unknown. The purpose of this study was to investigate neural and cardiovascular responses to emotional stress evoked by negative pictures and reexamine the relationship between muscle sympathetic nerve activity (MSNA) and perceived stress. Mean arterial pressure (MAP), heart rate (HR), MSNA, and perceived stress levels were recorded in 18 men during three randomized trials: 1 ) neutral pictures, 2 ) negative pictures, and 3 ) mental stress. MAP and HR increased during mental stress ( 14 ± 2 mmHg and 15 ± 2 beats/min, P < 0.001) but did not change during viewing of negative or neutral pictures. MSNA did not change during viewing of neutral ( 1 ± 1 burst/min, n = 16) or negative ( 0 ± 1 burst/min, n = 16) pictures or during mental stress ( 1 ± 2 burst/min, n = 13). Perceived stress levels were higher during mental stress (3 ± 0 arbitrary units) than during viewing negative pictures (2 ± 0 arbitrary units, P < 0.001). Perceived stress levels were not correlated to changes in MSNA during negative pictures ( r = 0.10, P = 0.84) or mental stress ( r = 0.36, P = 0.23). In conclusion, our results demonstrate robust increases in MAP and HR during mental stress, but not during emotional stress evoked by negative pictures. Although the influence of mental stress on MSNA remains unresolved, our findings challenge the concept that perceived stress levels modulate MSNA during mental stress. muscle sympathetic nerve activity; negative pictures; blood pressure; mental arithmetic Address for reprint requests and other correspondence: J. R. Carter, Dept. of Exercise Science, Michigan Technological Univ., 1400 Townsend Dr., Houghton, MI 49931 (e-mail: jcarter{at}mtu.edu )