How much of what you see is a hallucination? || Elizabeth Cox

A condition called Charles Bonnet Syndrome can cause blind patients to hallucinate scenes in vivid color.

fMRI studies show that these hallucinations activate the same brain areas as sight — areas that are not activated by imagination.

Other hallucinations also involve the same brain areas as real sensory experiences.

What's going on? Elizabeth Cox details the science of hallucinations.