The temporal window of visual processing throughout adulthood.

Abstract

Aging is associated with declines in various visual functions, including visual processing in the temporal domain. However, how visual processing in the temporal domain changes throughout adulthood remains unclear. To address this, we recruited 30 adults aged 20 to 70 years. By systematically manipulating the stimulus onset asynchrony (SOA) of external noise masks, we measured contrast thresholds in an orientation discrimination task across five SOA conditions and one no mask condition. We hypothesized that the threshold would change with age, and that this change would depend on the SOA condition. Our results showed that thresholds increased with age at all SOA conditions, except for the no mask condition. To further explore temporal processing dynamics, we applied the elaborated perceptual template model to the contrast thresholds, which allowed us to extract the temporal processing window-describing how visual processing efficiency varies over time. The model provided a good fit to the data for all participants. We then extracted the peak and full width at half maximum (FWHH) of the processing window, reflecting the maximum efficiency and temporal extend of processing window, respectively, from the best-fit model for each participant. Regression analysis revealed that the peak decreased, while the FWHH increased with age, indicating that the temporal window of visual processing became wider and less efficient as age increased. Our cross-sectional study suggests that our ability to process dynamic visual information gradually declines with age in two significant ways: a decrease in peak efficiency and increased vulnerability to temporal disturbances.