Noise, physiology, and human performance: the potential role of effort

Thirty-three male college students ages 18-31 were assigned to 2 levels of noise exposure and worked at 2 levels of effort while calculating the Norinder arithmetic task (M. Frankenhaeuser & U. Lundberg, 1977). As hypothesized, noise increased heart rate, norepinephrine, and cortisol only under high effort. Blood pressure did not change significantly. Reaction time slowed significantly under noise only when effort was low. Both self-report and epinephrine level confirmed the effort manipulation and showed that it was orthogonal to noise levels. These data support the adaptive costs hypothesis and have practical implications for industry. These implications include trade-offs of productivity and worker health, which may be dependent on management style.