An international team of neuroscientists has shown that a person's ability to see fine visual detail can be sharpened by simply staring for a few seconds at a rapidly flickering display.

These counter-intuitive findings of Derek Arnold from the University of Queensland, Melvyn Goodale from Western University and their collaborators were published by the high-impact journal Proceedings of the National Academy of Sciences.

The result arises from the fact that there are two major pathways carrying information from the eyes to the visual areas of the brain. One pathway is fast and carries out coarse processing of the visual scene; the other is slower but provides more detailed and fine-grained information. Staring for a while at a flickering field of visual 'noise' tires out the fast coarse-grained pathway and allows the pathway carrying fine-grained and detailed information to dominate.

It has long been thought that the fast pathway allows us to see visual motion or to detect the rapid appearance of an object, but contributes little to our perception of the form of objects. However, the new study shows that this is not the case.

"The improvement in one's ability to see fine detail after the coarse-grained pathway has been taken off line strongly suggests that both pathways contribute to our ability to see visual shapes and patterns," says Arnold, an Associate Professor in Queensland's School of Psychology. "Reducing the input from this pathway effectively 'de-blurs' the image."

Goodale, Director of Western's world-renowned Brain and Mind Institute, offers this potentially helpful life hack: "The next time you want to read the fine print on a form or on the back of a medicine bottle, which is a difficult task demanding a fine spatial vision, and you don't have a magnifying glass in your hand - you might want to first view a flickering display or a noisy computer screen."

Article: Sharpening vision by adapting to flicker, Derek H. Arnold, Jeremy D. Williams, Natasha E. Phipps, and Melvyn A. Goodale, PNAS, doi: 10.1073/pnas.1609330113, published online 17 October 2016.