People who do not remember their dreams have a faster cognitive decline. The study suggests a link to the risk of Alzheimer's.

A study conducted by the Centre for Healthy Brain Ageing (CHeBA) at the University of New South Wales has shown that individuals who do not remember their dreams experience cognitive decline twice as fast compared to those who do remember their dreams. Darren Lipnicki, a researcher at CHeBA, stated that dream recall may be an early indicator of Alzheimer's disease, even before memory is affected.

The study found that the inability to remember dreams is associated with the APOE4 gene, a major genetic risk factor for Alzheimer's, and with higher levels of the blood biomarker p-tau217. Lipnicki explained that early neurodegenerative changes could reduce dream production or make them less vivid. Participants who did not remember their dreams were more likely to develop dementia in the next ten years. This finding suggests that a simple assessment of dream recall could provide an accessible method for early identification of Alzheimer's risk, much earlier than current methods.