Age Difference on the Spatial Scale of Object Categorization.

Background: As the elderly population is growing worldwide and communication is increasingly relayed by visual interfaces, identifying age-related changes in the visual perception of complex stimuli is critical. We examined the effect of spatial frequency filtering on object categorization in young (mean 25 years) and older (mean 65 years) participants.

Method: The stimuli used were low spatial frequency (LSF, cutoff 8 cpi) or high spatial frequency (HSF, cutoff 24 cpi) images of objects of various categories, and hybrid images composed of a LSF object superimposed on a HSF object from a different semantic category. Participants were asked to press a key when they detected an object from a specified category (e.g., animal).

Results: Young participants categorized efficiently LSF and HSF images, and exhibited a bias towards the HSF component of hybrid images. Older participants showed a better performance on LSF than on HSF images and exhibited a strong bias towards the LSF component of hybrid image.

Conclusion: The results show that LSF are better preserved than HSF in older people. The greater interference of LSF than HSF in older than in young adults suggests that LSF are available earlier than HSF in older people.