The Time Machine revisited: An updated account of time-shifting in Alzheimer's Disease.

This article focuses on the phenomenon of time-shifting in dementia, particularly Alzheimer's Disease (AD), where individuals relive past events as if they are occurring in the present. It compares two models explaining time-shifting: the original Time Machine model, which attributes the phenomenon to hippocampal atrophy causing reliance on older memories, and the updated Time Machine 2.0, based on the Autobiographical Memory in Alzheimer's Disease (AMAD) model, which emphasizes disrupted connectivity in the Default Mode Network and a shift from episodic to semantic memory reliance. The revised model highlights the importance of the "reminiscence bump" (memories from ages 10 to 30) and the reconstructive nature of autobiographical memory, offering clinical implications for improving communication and care strategies by aligning with the person's self-identity and emotional needs. The update is specific to AD and cautions against generalizing to other dementia types.