Are visual feedback delays responsible for aging-related increases in force variability?

The current investigation examined if age-related differences in the control of isometric force production are related to an increase in visual motor processing time. Young and old adults produced isometric force production to a visually displayed target while visual feedback delay was manipulated over a broad range (50 to 3200 ms). The force output of the oldest age group was more variable across the range of delays, but only demonstrated enhanced time dependent structure at short delays. It is concluded that age differences in visual motor processing time contribute to decrements in both the feedback and feedforward control of force output.