The relationship between vigilance and monotonous work.

Forty subjects worked for 2 hours each at four different routine and monotonous tasks: (1) a simple vigilance task, (2) a bean-sorting task, (3) a simple assembly task, and (4) a two-digit addition task. S's performance was scored in terms of signals detected or number of work units produced and in terms of signals missed or number of errors made. The coefficients of concordance (Kendall's W) were statistically significant. Intercorrelations among the four tasks, however, showed that S's vigilance performance contributed to the overall agreement among the measures. It was concluded S's performance on the sorting task, for example, was predictable from their performance on assembling and adding. Vigilance performance, however, was not predictable from behaviour on the other tasks. The vigilance task, therefore, appears to contain elements not found in other monotonous work. It is suggested that two of these unique aspects are the lack of automaticity and the inability of S to control or pace his work rate.