Alterations in human upper extremity motor function during acute exposure to simulated altitude

Allan J Hamilton, L. A. Trad, A. Cymerman

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

We tested the hypothesis that mild motor dysfunction was associated with Acute Mountain Sickness (AMS) by measuring arm movement characteristics in 14 subjects at sea level and at the end of a 30-h simulated altitude exposure (4,600 m). A computerized upper extremity movement analyzer (UEMA) was used to quantitate arm movements between a ''start'' position and randomly-generated targets on a large digitizing tablet by measuring selected speed parameters and error indices. The UEMA results were compared with the results of the Environmental Symptoms Questionnaire (ESQ) and with neurologic examinations. When compared with sea-level values, the mean values for all the speed-related parameters measured at the end of the 30-h exposure significantly declined by 20% to 32%. The error indices were not different. The declines in the speed-related parameters were significantly correlated with the severity of AMS symptoms as measured by the ESQ (R = 0.82). The neurologic abnormalities were limited to changes in mental status items. These results demonstrate that subclinical alterations in upper extremity speed are associated with mild, reversible AMS and provide evidence that hypoxia may produce supraspinal inhibition of motor pathways.

Original languageEnglish (US)
Pages (from-to)759-764
Number of pages6
JournalAviation Space and Environmental Medicine
Volume62
Issue number8
StatePublished - 1991
Externally publishedYes

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Altitude Sickness
Upper Extremity
Oceans and Seas
Sea level
Arm
Nervous System Malformations
Efferent Pathways
Neurologic Examination
Tablets
Surveys and Questionnaires

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Pollution
  • Medicine(all)

Cite this

Alterations in human upper extremity motor function during acute exposure to simulated altitude. / Hamilton, Allan J; Trad, L. A.; Cymerman, A.

In: Aviation Space and Environmental Medicine, Vol. 62, No. 8, 1991, p. 759-764.

Research output: Contribution to journalArticle

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