Every year thousands of people are left with debilitating symptoms after stroke. Perhaps one of the most striking is known as hemispatial neglect. This is when right-sided brain damage causes people to behave as though the left half of the world does not exist.
This problem arises when damage to the right parietal cortex disrupts the connections linking visual areas at the back of the brain with motor systems towards the front. The damage leaves the stroke survivor unable to voluntarily direct attention towards, and act on, visual objects in the space to their left.
Hemispatial neglect is very common, affecting many patients in the early months after stroke. Most recover over time, but about one-third do not, and suffer neglect as a lasting disabling condition.