Citation

Hart SG, Sellers JJ, Guthart G. Proc. Hum. Factors Ergon. Soc. Annu. Meet. 1984; 28(8): 732-736.

Copyright

(Copyright © 1984, Human Factors and Ergonomics Society, Publisher SAGE Publishing)

DOI

10.1177/154193128402800822

PMID

unavailable

Abstract

The influence of variations in response selection and response execution difficulty on the workload and performance of 11 experimental subjects was investigated. The 20 laboratory tasks they performed involved a binary response selection that required different levels of mental processing (e.g. choice reaction time, prediction, memory search, etc.). A target acquisition task was added following response selection on half of the trials. A weighted combination of bipolar ratings on nine workload-related dimensions was used to evaluate the workload experienced by the subjects. In addition, subjects rank-ordered the tasks with respect to workload before (a prediction) and again after (a retrospective comparison) performing them. Apparently minor variations in stimulus presentation resulted in significantly increased reaction times and workload ratings, as did the more obvious manipulations of response selection load. The addition of the target acquisition task increased workload ratings and reaction tines, however the "cost" of performing the two-stage task (as indicated by measures of speed, accuracy, and subjective opinion) was considerably less than would be expected by combining measures for the component tasks. Movement times for the target acquisition tasks increased significantly as a function of the index of difficulty of the target, but were not affected by the difficulty of the response selection task.

Language: en