Older adults experience some benefit, but less than young adults, from training to use their peripheral vision to read text, according to a new study.
Enhancing reading ability in peripheral vision is important for the rehabilitation of people with central-visual-field loss from age-related macular degeneration (AMD). Previous research
has shown that perceptual learning, based on a trigram letter-recognition task, improved peripheral reading speed among normally-sighted young adults. Here the researchers investigate whether the same happens in older adults in an age range more typical of the onset of AMD.
Eighteen normally-sighted subjects, aged 55 to 76 years, were randomly assigned to training or control groups. Visual-span profiles (plots of letter-recognition accuracy as a function of horizontal letter position) and RSVP reading speeds were measured at 10 degrees above and below fixation during pre- and post-tests for all subjects. Training consisted of repeated measurements of visual-span profiles at 10 degrees below fixation, in 4 daily sessions. The control subjects did not receive any training.
Perceptual learning enlarged the visual spans in both trained (lower) and untrained (upper) visual fields. Reading speed improved in the trained field by 60% when the trained print size was used. The training benefits for these older subjects were weaker than the training benefits previously found for young adults.
Despite the weaker training benefits, perceptual learning remains a potential option for low-vision reading rehabilitation among older adults.Source:Vision Res. 2010 Feb 12. [Epub ahead of print]