September 15, 2026
You’re hurrying out of the grocery story to drive home and start cooking dinner. As the doors close behind you, you step into the parking lot and head… where? Where, among the rows of gleaming vehicles, did you park your car? The memory seems to have disappeared.
One important form of memory, episodic memory, is the recollection of these kinds of moments in life. Episodic memories are an important part of how we create long-term memories. They could be of something that happened long ago, such as your first day of elementary school, or as recent and everyday as the parking spot you maneuvered into before going into the grocery store.
As we age, our episodic memory gets weaker. Sensory details of life’s moments become harder to recall, though scientists don’t yet know why. This is true for almost all of us, but for some people, including those who are developing Alzheimer’s disease, the scale of memory loss can be devastating.
New research by UC Berkeley neuroscientist Omer Sharon and colleagues, directed by former Berkeley sleep researcher Matthew Walker, may help explain why. The researchers identified a link between changes in brain wave patterns during non-REM sleep, poorer episodic memory formation and buildup of the protein tau, a known marker for development of Alzheimer’s disease, in the brain’s frontal cortex.
