Effects of age and eccentricity on visual target detection.
The aim of this study was to examine the effects of aging and target eccentricity on a visual search task comprising 30 images of everyday life projected into a hemisphere, realizing a ±90° visual field. The task performed binocularly allowed participants to freely move their eyes to scan images for an appearing target or distractor stimulus (presented at 10°; 30°, and 50° eccentricity). The distractor stimulus required no response, while the target stimulus required acknowledgment by pressing the response button. One hundred and seventeen healthy subjects (mean age = 49.63 years, SD = 17.40 years, age range 20-78 years) were studied. The results show that target detection performance decreases with age as well as with increasing eccentricity, especially for older subjects. Reaction time also increases with age and eccentricity, but in contrast to target detection, there is no interaction between age and eccentricity. Eye movement analysis showed that younger subjects exhibited a passive search strategy while older subjects exhibited an active search strategy probably as a compensation for their reduced peripheral detection performance.
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland.
Nicole
N
Gruber
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland ; Perception and Eye Movement Laboratory, Departments of Neurology and Clinical Research, University Hospital Inselspital, University of Bern Bern, Switzerland.
René M
RM
Müri
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland ; Department of Old Age Psychiatry, University Hospital of Psychiatry, University of Bern Bern, Switzerland.
Urs P
UP
Mosimann
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland.
Rahel
R
Bieri
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland.
Andrea
A
Aeschimann
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland.
Giuseppe A
GA
Zito
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland.
Prabitha
P
Urwyler
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland ; Perception and Eye Movement Laboratory, Departments of Neurology and Clinical Research, University Hospital Inselspital, University of Bern Bern, Switzerland ; Center of Neurology and Neurorehabilitation, Luzerner Kantonsspital Luzern, Switzerland.
Thomas
T
Nyffeler
Gerontechnology and Rehabilitation Group, University of Bern Bern, Switzerland ; ARTORG Center for Biomedical Engineering Research, University of Bern Bern, Switzerland.
Tobias
T
Nef
aging; functional visual field; target detection; visual exploration behavior; visual search; visual search strategy