The question
How can reduced input from the eyes coexist with vivid visual experiences?
Overview
Charles Bonnet syndrome involves visual hallucinations after substantial sight loss. The NHS information describes patterns, people, animals or scenes that may be moving or still. Most affected people know that the images are not real.
The evidence
The NHS links the syndrome to reduced visual input. Its explanation is that the brain may create images when it receives less information from the eyes. These experiences concern vision; hearing or feeling things is not part of the visual-only presentation described there.
Interpretation
This is an important distinction for the wider study of perception. A hallucination is a description of an experience, not a diagnosis on its own. Charles Bonnet syndrome is not caused by a mental health problem or dementia. It illustrates why the sensory and medical context matters.
Limits
The public explanation is not a complete model of every person’s visual processing. New hallucinations should be assessed: the NHS recommends an urgent GP appointment or NHS 111 to exclude other causes. This page cannot establish that a reported experience is Charles Bonnet syndrome.
Source register
Follow the evidence.
Linked research and official information used for this note. Inclusion identifies a source; it does not imply that the source has reviewed this website.
NHS: Charles Bonnet syndrome ↗