Extreme body cooling and psychomotor performance.

Abstract In a series of experiments on the effect of body cooling ( the lowering of Mean Weighted Skin Temperature (MVVST) while maintaining normal Hand Skin Temperature (HST)) on psychomotor performance, the following results were obtained. (I) Block-stringing (BS) and block-packing (BP) performance decreased linearity across levels of body cooling (MWST's of 78° 74° 70° and 66° f). (2) Body cooling (MWST— 70° f) affected steadiness-aiming (SA) performance, but did not affect performance on the Craik screw task, the Purdue pegboard assembly ( PA) task and the two-plate-tapping task. (3) The effect of level of body cooling on SA performance was similar for fast and slow cooling rates. Significant BS and PA performance decrements occurred only under the low level (70° f MWST) and slow rate (90 min exposure) condition. (4) Increasing the duration of exposure for 20 and 40 min after a given MWST condition was attained resulted in significant decreases in BS performance. (5) Practice resulted in improved BS p...