Can adults still train binocular vision?

The old view was that visual plasticity exists only in the childhood critical period -- miss it and the system is fixed. Two decades of research have changed that: the adult visual system keeps a measure of plasticity too.

Multiple studies have observed adults improving in contrast sensitivity, fusion range and stereopsis through perceptual learning and dichoptic training. The gains vary from person to person and usually come slower than in children.

For adults the biggest obstacle is usually not the effect but the persistence -- the exercises themselves are repetitive and dull. Making them games, with progress recorded automatically, genuinely helps keep the training going.

If you are an adult thinking about training, get a full eye examination first, understand your own situation, and discuss realistic goals and expectations with your doctor.