Brain stimulation can reduce the effects of macular degeneration

September 22, 2020

Visual cortex stimulation improves peripheral vision in observers with normal vision

A study conducted by the University of Waterloo’s School of Optometry found the use of brain stimulation can help people with macular degeneration recover vision.1 More specifically, a single, 20-minute session of non-invasive visual cortex stimulation results in improved macular degeneration effects.

Those who suffer with macular degeneration often lose central vision and must rely on peripheral vision. Further difficulties arise when crowding or segregating an object from others that are in close proximity, appears.

Interventions like transcranial direct current stimulation (tDCS) directly reduce mechanisms in the visual cortex that contribute to crowding. This can improve vision in patients with central vision loss especially when combined with perceptual learning techniques.

“Perceptual learning can reduce letter crowding for patients with macular degeneration. However, perceptual learning typically requires intensive training, which may be a barrier for patients,” said Ben Thompson, professor at the School of Optometry and Vision Science, in a statement. “Additionally, the learning does not always transfer to non-trained stimuli, that’s why this discovery is so promising, it addresses all of these concerns.”

This study is a step toward applications of non-invasive brain stimulation to recover vision in patients with macular degeneration, according to the researchers.

“Results of this study lay the foundation for future work investigating whether a-tDCS may be useful as a visual rehabilitation tool for individuals with central vision loss who are reliant on peripheral vision,” said Thompson.

Reference

1. Raveendran RN, Tsang K, Tiwana D, Chow A, Thompson B. Anodal transcranial direct current stimulation reduces collinear lateral inhibition in normal peripheral vision. PLoS One. 15(5):e0232276.