HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 288/2/H904    most recent 00569.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by Carter, J. R. Articles by Ray, C. A. Search for Related Content PubMed PubMed Citation Articles by Carter, J. R. Articles by Ray, C. A.

Forearm neurovascular responses during mental stress and vestibular activation

¹Departments of Medicine and Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania; ²Department of Biological Sciences, Michigan Technological University, Houghton, Michigan; and ³United States Army Institute of Surgical Research, Fort Sam Houston, Texas

Submitted 14 June 2004 ; accepted in final form 7 October 2004

Autonomic responses may underlie associations among anxiety, vestibular dysfunction, and unexplained syncope. Mental stress (MS), an anxiety-inducing stimulus, causes forearm vasodilation, whereas the vestibulosympathetic reflex (VSR) causes forearm vasoconstriction. The purpose of this study was to examine the combined effects of mental and vestibular stimulation on neurovascular control in the forearm. Heart rate, arterial pressure (Finapres), and forearm blood flow (Doppler) were measured in 10 healthy volunteers in the prone position during 1) head-down rotation (HDR), 2) MS (mental arithmetic), and 3) HDR + MS. Forearm vascular resistance (FVR) increased during HDR (from 232 ± 40 to 319 ± 53 units) and decreased during MS (from 260 ± 57 to 154 ± 22 units). During HDR + MS, FVR did not change [change () = –31 ± 50 units] and was not significantly different from the algebraic sum of each trial performed alone ( = –20 ± 42 units). Arm muscle sympathetic nerve activity (MSNA; microneurography) was measured in seven additional subjects. MSNA increased during HDR (from 13 ± 2 to 17 ± 2 bursts/min) and HDR + MS (from 11 ± 2 to 16 ± 2 bursts/min). Increases in MSNA during HDR + MS ( = 5 ± 2 bursts/min) were not different from the algebraic sum of each trial performed alone ( = 6 ± 2 bursts/min). We conclude that an additive neurovascular interaction exists between MS and the VSR in the forearm. Activation of the VSR prevented forearm vasodilation during MS, suggesting that activation of the VSR may help protect against stress-induced syncope.

otolith stimulation; vestibulosympathetic reflex; arterial pressure control; mental arithmetic

This article has been cited by other articles:

				N. T. Kuipers, C. L. Sauder, J. R. Carter, and C. A. Ray Neurovascular responses to mental stress in the supine and upright postures J Appl Physiol, April 1, 2008; 104(4): 1129 - 1136. [Abstract] [Full Text] [PDF]

				J. R. Carter and C. A. Ray Sympathetic responses to vestibular activation in humans Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2008; 294(3): R681 - R688. [Abstract] [Full Text] [PDF]

				T. E. Wilson, C. L. Sauder, M. L. Kearney, N. T. Kuipers, U. A. Leuenberger, K. D. Monahan, and C. A. Ray Skin-surface cooling elicits peripheral and visceral vasoconstriction in humans J Appl Physiol, October 1, 2007; 103(4): 1257 - 1262. [Abstract] [Full Text] [PDF]

				D. J. Dyckman, K. D. Monahan, and C. A. Ray Effect of baroreflex loading on the responsiveness of the vestibulosympathetic reflex in humans J Appl Physiol, September 1, 2007; 103(3): 1001 - 1006. [Abstract] [Full Text] [PDF]

				Y. Noto, T. Sato, M. Kudo, K. Kurata, and K. Hirota The Relationship Between Salivary Biomarkers and State-Trait Anxiety Inventory Score Under Mental Arithmetic Stress: A Pilot Study. Anesth. Analg., December 1, 2005; 101(6): 1873 - 1876. [Abstract] [Full Text] [PDF]