The Effect of Mild Hyperbaria on the Performance of a Reaction Time Test and Profile of Mood States

Changes in barometric pressure may be related to how people feel and how they perform. It is known that a decrease in the partial pressure of oxygen in the ambient air, which results from high altitude or hypoxia, causes decreased oxygen saturation in the blood and related performance decrement (1). Conversely, it has been shown that an increase in the partial pressure of oxygen in ambient air, associated with hyperbaria or hyperoxia, can lead to improved physical performance (2,3). Mild hyperbaria is known to cause a decrease in heart rate and ventilation (2,4). The effect of very small changes in barometric pressure, for example, those associated with changes in weather patterns, on feelings of well being or performance of routine work tasks, however, is not known. This is significant because millions of workers are routinely exposed to changes in barometric pressure as a result of alterations in weather patterns. The purpose of this study, therefore, was to examine the effects of very mild hyperbaria (0.5 psi; 20 mmHg) on the profile of mood states (POMS) and performance on a computerized reaction time test (Rn) in young, healthy subjects.