Neural changes related to motion processing in healthy aging

Behavioral studies have found a striking decline in the processing of low-level motion in healthy aging whereas the processing of more relevant and familiar biological motion is relatively preserved. This fMRI study investigated the neural correlates of low-level radial motion processing and biological motion processing in 19 healthy older adults (age range 62-78 years) and in 19 younger adults (age range 20-30 years). Brain regions related to both types of motion stimuli were evaluated and the magnitude and time-courses of activation in those regions of interest were calculated. Whole-brain comparisons showed increased temporal and frontal activation in the older group for low-level motion but no differences for biological motion. Time-course analyses in regions of interest known to be involved in both types of motion processing likewise did not reveal any age-differences for biological motion. Our results show that low-level motion processing in healthy aging requires the recruitment of additional resources, whereas areas related to the processing of biological motion processing seem to be relatively preserved.