Dimensional analysis of motion: VIII. The role of visual discrimination in motion cycles

Abstract

To determine the changes that occur in the duration of component movements of a motion cycle when a specific visual discrimination is imposed on part of the cycle, electronic recordings were made of the durations of the component movements of an assembly task. Although conventional time-motion study based on the therblig system calls for the application of the therblig "select" when a choice is required, implying an operation that can be separately timed, "Results of the present study… indicate that the durations of all four components of a cyclic sequential movement pattern are increased significantly by the addition of a specific visual discrimination." The adequacy of the therblig system for handling perceptual components of a task is questioned. (PsycInfo Database Record (c) 2025 APA, all rights reserved)