Brain regions exhibit sleep-wake flicker, groundbreaking study reveals
In a pioneering discovery, scientists from Washington University in St. Louis (WashU) and the University of California Santa Cruz (UCSC) have found that certain brain regions experience microsecond-long naps while we are awake. Using advanced tools and computational techniques, the scientists observed unique patterns in brain waves, where small brain regions would momentarily shut down during wakefulness and revive during sleep. Keith Hengen, Assistant Professor of Biology at WashU, emphasized the importance of challenging fundamental assumptions about states of consciousness.
Study challenges traditional understanding of sleep-wake states
The conventional classification of sleep and wake states, based on distinct brain wave patterns like alpha, beta, theta when awake, and delta during sleep, is now being questioned by these "flicker" phenomena. Over a four-year study involving mice, researchers monitored brain-wave voltages across 10 brain regions. Employing artificial neural networks, they sifted through petabytes of data to pinpoint microsecond anomalies overlooked in human studies. David Haussler, Professor of Biomolecular Engineering at UCSC, noted unprecedented level of detail in their findings.
Machine learning unveils new insights into brain activity
Using machine learning techniques, researchers identified that intense neuronal activity between specific neurons in one brain region plays a crucial role in sleep. Conversely, they noted decreased activity during periods conventionally categorized as wakefulness, which they referred to as "flickers." Aidan Schneider, a researcher at WashU, emphasized how examining individual firing times of neurons revealed clear transitions between states. This discovery introduces further complexity to our comprehension of brain function during different phases of sleep and wakefulness.
Study observes mice 'Zoning out' during micro-naps
The researchers also noticed that mice seemed to "zone out" during these split-second micro-naps and twitched during sleep at these same "flicker" moments. Hengen noted that they have observed flickers between wake and REM sleep, as well as between REM and non-REM sleep—combinations that defy expectations based on a century of literature on the subject. These observations challenge long-standing assumptions about sleep-wake states and could potentially revolutionize our understanding of brain function in both animals and humans.
Findings could illuminate neurodevelopmental and neurodegenerative diseases
The findings of this study could provide new insights into neurodevelopmental and neurodegenerative diseases linked to sleep dysregulation. Hengen suggested that this discovery provides a potentially powerful tool to delve deeply into the understanding of diseases and disorders. The research, which offers a fresh perspective on the intricate workings of the brain during different states of consciousness, was published in the journal Nature Neuroscience. This groundbreaking work could pave the way for novel approaches in understanding and treating neurological disorders.
