Check out this answer from Consensus:
While déjà vu is a common and usually benign experience, persistent déjà vu can be indicative of underlying neurological conditions, including Alzheimer’s disease. The phenomenon’s association with memory disorders and specific brain regions highlights the importance of further research to understand its mechanisms and implications fully. For individuals experiencing frequent or persistent déjà vu, especially those with other cognitive symptoms, seeking medical evaluation is advisable.
Déjà vu, a French term meaning “already seen,” is a phenomenon where an individual feels an uncanny sense of familiarity with a situation that they know is novel. This experience is common, with estimates suggesting that around 60% of people have encountered it at least once in their lives1. While often fleeting and benign, persistent déjà vu can be indicative of underlying neurological conditions. This article explores whether déjà vu can be a sign of Alzheimer’s disease, drawing on recent research findings.
Understanding Déjà Vu
Déjà vu is typically characterized by a brief, unsettling sensation that a current experience has been lived through before. It is more frequently reported under conditions of stress and fatigue and tends to decline with age1. The phenomenon is notably more prevalent among individuals with schizophrenia and temporal lobe epilepsy, suggesting a neurophysiological basis involving the temporal lobe1.
Persistent Déjà Vu and Memory Disorders
Persistent déjà vu, or déjà vécu (the sensation that events have been lived through before), is a more severe form of the phenomenon. It is often accompanied by significant memory problems, such as poor short-term recall, and can severely impact daily activities1. This persistent form has been observed in patients with various memory disorders, including dementia and transient epileptic amnesia (TEA)2.
Déjà Vu in Alzheimer’s Disease
Alzheimer’s disease is a progressive neurodegenerative disorder characterized by memory loss, cognitive decline, and behavioral changes. While déjà vu is not a definitive sign of Alzheimer’s, it can occur in the context of the disease. The phenomenon in Alzheimer’s patients may be linked to the dual process view, where erroneous familiarity and recollection are triggered by inappropriate activation of the parahippocampal cortex and the hippocampus2. This aligns with the encoding-as-retrieval hypothesis, which suggests that normal memory encoding processes are mistakenly interpreted as memory retrieval2.
Neuroanatomical Correlates
Recent neuroimaging studies have identified structural brain differences in individuals who experience déjà vu. Specifically, there is less gray matter in cortical and subcortical regions, predominantly in the mesiotemporal areas, among those reporting déjà vu3. These findings suggest an alteration in hippocampal function, which is crucial for memory formation and retrieval, and may provide a pathogenetic link between nonpathological and epileptic déjà vu3.
Is deja vu a sign of Alzheimer’s?
George Perry has answered Extremely Unlikely
An expert from University of Texas at San Antonio in Neurodegenerative Disease, Alzheimer’s Disease, Parkinson’s Disease, Metabolomics
Not to my knowledge