Visual rehabilitation of children with visual impairments

Visual rehabilitation, consisting of visual stimulation and visual training, is a common practice in the education of children with visual impairments. Ferrell and Muir have stated that scientific research into the effects of visual stimulation and training is ambiguous and that therefore stimulation and training should be abandoned. The support for this statement is reviewed by describing the scientific relevance and plausibility of the aims and presuppositions of visual stimulation and training programs as well as the results of 10 empirical intervention studies. The review results are in strong agreement with the claim of Ferrell and Muir to abandon noncontingent visual stimulation. It is hypothesized that it is possibly counterproductive for the adaptive functioning of the brain to show strong visual stimuli in artificial surroundings, which are noncontingent on the behavior of the child. Training of visual functions seems fruitful whenever skills that are ecologically valid and adapted to the individual needs and task demands of the child are trained. However, the empirical evidence is still too sparse to draw convincing conclusions. There is an urgent need for good randomized controlled trials with dependent variables that are relevant to everyday life.

The Effects on Visually Impaired Children of Viewing Fluorescent Stimuli under Black-Light Conditions

In this study, 30 children with low vision (divided into a high and a low visual acuity group) were presented with stimuli under four conditions (white stimuli-white light, orange stimuli-white light, white stimuli-black light, and orange stimuli-black light) and were asked to rank their preferences for the four conditions. The goal was to determine the effects of the various combinations of stimuli and lighting on the children's visual performance. The orange stimuli viewed under black light resulted in the best performance overall, benefited the low-acuity group more than the high-acuity group, and was the most-preferred condition for both groups.