Sight and Perception in Dementia

Difficulty seeing clearly and difficulty interpreting what is seen are different problems. A person living with dementia may experience either or both.

Notice what is difficult

Record examples, such as missing an object or misjudging a step. Arrange appropriate sight checks and discuss new or troubling visual experiences with a healthcare professional.

Try a focused adjustment

Compare the same task in better light or with fewer competing objects. Make one change at a time and observe whether it helps. Involve the person before changing a familiar room.

Sudden change

The NHS advises calling 999 if someone suddenly becomes confused. Do not assume an abrupt change is simply progression of dementia.

Further reading

• Alzheimer’s Society: sight and hearing loss
• Alzheimer’s Society: changes in perception
• NHS: sudden confusion

Editorial review: 7 October 2026.