A comparison of the influence of handle load and of unfavourable atmospheric conditions on a tracking task

An experiment was made to determine the extent to which the performance of a tracking task was adversely influenced by simulated tropical environmental conditions, by comparing this effect with that of loading the control handle with weights. The pursuitmeter used was similar to that used by Mackworth (1948) when he showed that the accuracy of performance was reduced under tropical conditions. The score of error was the total angular separation between the target and follower pointers expressed in arbitrary units. It was found that as the room temperature was raised from approximately 80° to 90° on the Effective Temperature scale, this score increased in the ratio 1-13, an increase which was also obtained by increasing the load on the control handle from 8 to 30 lb. There were also indications that the effect of room temperature was greater with higher handle loads. The effect on performance was not correlated with rectal temperature or with the amount of weight lost.