title: Residual abilities in age-related macular degeneration to process spatial frequencies during natural scene categorization.
abstract: Age-related macular degeneration (AMD) is characterized by a central vision loss. We explored the relationship between the retinal lesions in AMD patients and the processing of spatial frequencies in natural scene categorization. Since the lesion on the retina is central, we expected preservation of low spatial frequency (LSF) processing and the impairment of high spatial frequency (HSF) processing. We conducted two experiments that differed in the set of scene stimuli used and their exposure duration. Twelve AMD patients and 12 healthy age-matched participants in Experiment 1 and 10 different AMD patients and 10 healthy age-matched participants in Experiment 2 performed categorization tasks of natural scenes (Indoors vs. Outdoors) filtered in LSF and HSF. Experiment 1 revealed that AMD patients made more no-responses to categorize HSF than LSF scenes, irrespective of the scene category. In addition, AMD patients had longer reaction times to categorize HSF than LSF scenes only for indoors. Healthy participants' performance was not differentially affected by spatial frequency content of the scenes. In Experiment 2, AMD patients demonstrated the same pattern of errors as in Experiment 1. Furthermore, AMD patients had longer reaction times to categorize HSF than LSF scenes, irrespective of the scene category. Again, spatial frequency processing was equivalent for healthy participants. The present findings point to a specific deficit in the processing of HSF information contained in photographs of natural scenes in AMD patients. The processing of LSF information is relatively preserved. Moreover, the fact that the deficit is more important when categorizing HSF indoors, may lead to new perspectives for rehabilitation procedures in AMD.
authors.affiliation: Laboratoire de Psychologie et NeuroCognition, Centre National de la Recherche Scientifique UMR 5105, Université Pierre Mendès France, Grenoble, France. benoit.musel@upmf-grenoble.fr
authors.forename: Benoit
authors.initials: B
authors.lastname: Musel
authors.forename: Ruxandra
authors.initials: R
authors.lastname: Hera
authors.forename: Sylvie
authors.initials: S
authors.lastname: Chokron
authors.forename: David
authors.initials: D
authors.lastname: Alleysson
authors.forename: Christophe
authors.initials: C
authors.lastname: Chiquet
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Romanet
authors.forename: Nathalie
authors.initials: N
authors.lastname: Guyader
authors.forename: Carole
authors.initials: C
authors.lastname: Peyrin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008268:Macular Degeneration / Q000503:physiopathology*; D008297:Male; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*