Unraveling Multiregional Neural Patterns during Consciousness Transition Using Flexible Microelectrode Arrays Integrated with Neuropixels Chips.

Consciousness transitions, including awakening from anesthesia or falling asleep, involve complex neural dynamics across multiple brain regions. Understanding these transitions requires simultaneous and stable monitoring of large-scale neural activity in freely moving animals. Here, a flexible microelectrode array system (FlexiPixels probe) is demonstrated that integrates a multishank flexible microelectrode array with Neuropixels chips. This lightweight FlexiPixels probe enables stable and long-term neural signal recording across multiple brain regions in freely moving rats and tracking of neuronal activities during consciousness transitions from anesthesia to wakefulness and subsequent sleep states. Distinct state-dependent firing patterns emerge across different brain regions and neuronal types. CA1 neurons show similar activity during wakefulness and sleep, while DG neurons exhibit unique anesthesia sensitivity. These findings demonstrate FlexiPixels' capabilities for stable multiregion neural recording in freely moving animals and potential to unravel region-specific signatures in consciousness studies.