Brain cells meant to protect us may drive cognitive decline, new study suggests

A report from ScienceDaily in October 2026 describes research showing that brain cells usually considered protective can malfunction. When they do, they may produce excessive myelin, which can interfere with nerve fibers and contribute to declines in memory and thinking. The findings suggest brain circuits can disrupt themselves when misconfigured rather than always working in our favor. The article also links this idea to amblyopia, where the brain's visual processing favors the stronger eye, and argues that learned patterns may be modifiable through repeated training, though evidence for adults remains under study.