A Systematic Review Based Analysis of Eye-Hand Movement Onset Asynchrony Adjustments

Abstract

When goal-directed hand movements are made, there is a common coordination pattern whereby the eyes start to move towards the target just before the hand. Onset asynchrony is the measurement of this latency. Onset asynchrony can be used to investigate the effects of neurological conditions on movement planning abilities. However, it is difficult to design a robust experiment since there is no clear understanding of why onset asynchronies change between conditions, and which elements of a task are likely to result in a change. This review aims to develop a coherent analysis of why people adjust their onset asynchrony for different situations. A systematic review methodology was employed to obtain all available research containing measurements of onset asynchrony. Searches returned 3703 articles, of which there were 38 articles that used onset asynchrony measurements as a dependent variable. In total, 30 potential onset asynchrony factors were investigated by the articles, with 25 of them affecting the timing between hand and eye onset. Generally, the eye guides the end of the previous movement, the start of the current movement, and the end of the current movement. It appears that onset asynchrony varies based on these competing requirements. When designing an experiment, one should be aware that the independent variable is likely to interact with these requirements. The experimental design must ensure that confounding factors/covariant observations are minimised.