Aging and perception of visual form from temporal structure.

Abstract

In this study, the authors examined age-related changes in participants' ability to perceive global spatial structure defined by temporal fine structure among elements undergoing rapid, irregular change. Participants were also tested on a task involving form recognition from luminance contrast and on a task dependent on perception of 3-dimensional shape from motion. Compared with young adults, older individuals were less sensitive to spatial form defined by temporal structure. In contrast, older observers performed as well as young adults on the other two tasks that were not dependent on temporal sensitivity, ruling out nonsensory factors as the cause of the deficits on the temporal structure task. This selective deficit may reveal reduced sensitivity within the temporal impulse response of the aging visual system, a deficit that could be related to reduced effectiveness of neural inhibition.

Aging and vision

“…For example, older adults have exhibited deficits in using motion to extract self-motion information (Warren, Blackwell & Morris, 1989), to perceive shape (Blake, Rizzo & McEvoy, 2008; Norman, Bartholomew & Burton, 2008; Norman, Clayton, Shular & Thompson, 2004; Norman, Dawson & Butler, 2000; Wist, Schrauf & Ehrenstein, 2000), and to identify collision paths (Andersen, Cisneros, Saidpour & Atchley, 2000; Anderson & Enriquez, 2006). Under certain stimulus conditions older adults also show deficits in the perception of biological motion (Billino, Bremmer & Gegenfurtner, 2008; Norman, Payton, Long & Hawkes, 2004), which may stem from difficulties in efficiently integrating local motion cues with global motion information (Pilz, Bennett & Sekuler, 2010).…”

Age-related deficits in inhibition in figure-ground assignment

“…The results showing that figure-ground perception entails inhibition together with the evidence for a decline in the efficiency of inhibitory processes with age leads to the prediction that figure-ground perception should be impaired in older compared to younger adults. Indeed, Blake, Rizzo, and McEvoy (2008) showed that figure-ground perception based on temporal structure differences between two regions in a display was impaired in older compared to younger adults when the task was difficult (i.e., when the temporal structure difference between the two regions was small). Blake et al hypothesized that their results could be explained by reductions in the strength of the inhibitory component of a biphasic (excitatory and inhibitory) temporal filter necessary to perceive figureground from temporal structure.…”

Similar behaviour, different brain patterns: Age-related changes in neural signatures of ignoring

“…Third, whilst for young adults, activation in sensory regions for attended items increases and to ignored items decreases (compared to a neutral baseline), older adults show only the increases in activation for attended items (Gazzaley et al, 2005a,b). Finally, older adults have worse temporal resolution than younger adults (Andersen and Ni, 2008;Blake et al, 2008).…”