Context:
New research by UC Berkeley neuroscientist Omer Sharon and colleagues, directed by former Berkeley sleep researcher Matthew Walker, 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.
Research and Key Findings:
During non-REM sleep, neurons shut down in slow, synchronized waves that move across the brain, beginning in the frontal cortex. As we age, tau proteins build up in many people’s brains. For them, these waves become irregular and less synchronized and travel shorter distances.
The researchers used electroencephalograms (EEGs) to measure brain waves during sleep, comparing cognitively healthy participants in their early 20s with those in their mid-60s to mid-70s. In the younger adults, clusters of slow brain waves traveled roughly the length of a handspan across the scalp during non-REM sleep. In the older adults, the waves traveled shorter distances and were more solitary.
Using positron emission tomography (PET) scans, the researchers found that the buildup of tau in the frontal cortex of older participants correlated with those long wave breakdowns. People with more solitary, shorter-reaching slow waves — what the researchers called “lonely waves” — remembered less material.
Why It Matters:
This slow-wave breakdown is linked to dwindling memory consolidation, cognitive decline and the development of Alzheimer’s disease. And though it remains unclear to researchers why memory loss is correlated with aging, the findings suggest that the connection is more complex than previously thought.
[OP] UCBerkeley | a day ago
Study published in Nature Neuroscience on September 11, 2026. Berkeley News coverage here.
Context:
New research by UC Berkeley neuroscientist Omer Sharon and colleagues, directed by former Berkeley sleep researcher Matthew Walker, 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.
Research and Key Findings:
During non-REM sleep, neurons shut down in slow, synchronized waves that move across the brain, beginning in the frontal cortex. As we age, tau proteins build up in many people’s brains. For them, these waves become irregular and less synchronized and travel shorter distances.
The researchers used electroencephalograms (EEGs) to measure brain waves during sleep, comparing cognitively healthy participants in their early 20s with those in their mid-60s to mid-70s. In the younger adults, clusters of slow brain waves traveled roughly the length of a handspan across the scalp during non-REM sleep. In the older adults, the waves traveled shorter distances and were more solitary.
Using positron emission tomography (PET) scans, the researchers found that the buildup of tau in the frontal cortex of older participants correlated with those long wave breakdowns. People with more solitary, shorter-reaching slow waves — what the researchers called “lonely waves” — remembered less material.
Why It Matters:
This slow-wave breakdown is linked to dwindling memory consolidation, cognitive decline and the development of Alzheimer’s disease. And though it remains unclear to researchers why memory loss is correlated with aging, the findings suggest that the connection is more complex than previously thought.