Laura D. Lewis
Neuromodulation of Neural Dynamics and Perception Across Sleep and Wakefulness
Sleep transforms nearly every aspect of brain function and cognition, and is essential for the healthy brain. Previous landmark studies have identified key control switches in the brain that regulate arousal state by releasing neuromodulatory substances such as serotonin. However, how these neurochemical pathways act on large-scale network dynamics to alter cognition is not well understood. Studying the large-scale brain circuitry regulating sleep and arousal states poses significant technical challenges, particularly when limited to noninvasive techniques that can be used in humans. My lab uses advanced neuroimaging technologies to understand the systems-level neural mechanisms underlying sleep and arousal in the human brain.
Our research integrates computational approaches and multiple imaging techniques to detect new aspects of human brain function during sleep. We use these techniques to identify key brain circuits that control sleep, and how they shape the brain’s responses to the external world across sleep and wakefulness. We are examining the network dynamics that underlie distinct sleep states, to explore how neuromodulatory states alter brain computation. We are also studying transitions between arousal states, aiming to identify what brain circuits engage at the moment of awakening, or throughout the descent into sleep.
In a parallel line of research, my lab also examines how sleep affects brain vascular physiology, to identify the role of these neuromodulators and circuits in the unique blood flow and cerebrospinal fluid (CSF) flow dynamics that appear in sleep. These blood and CSF dynamics are critical for maintaining brain health, and are thought to be disrupted in neurological disorders. Together, these studies aim to identify how sleep jointly modulates both high-level cognition and the basic physiological health of the brain.