Sleep serves a restorative function for the brain and cognition and involves dramatic changes to our perception and consciousness. Our goal is to understand how sleep relates to cognition and perception.
Research projects in the lab:
State-dependent cortical processing
Why are we disconnected from external stimuli in sleep? Do sleep-like processes also affect cognitive unresponsiveness when we are awake but inattentive?
Reduced responsiveness is a defining property of sleep but we still do not understand the neuronal mechanisms that underlie such disconnection. Behavioral states of wakefulness, sleep and anesthesia dramatically affect the brain’s excitability and responses, and determine whether sensory stimuli will be perceived, induce plastic changes and trigger behavior. More generally, sleep is a powerful model for how the internal state of electrical activity and neuromodulation can determine the processing of sensory stimuli. States of brain activity also dynamically change when we are awake and our brain continuously adapts to behavioral demands in the contexts of attention and expectation. We are investigating whether both sleep/wake states and cognitive factors may modulate cortical responsiveness via shared mechanisms. We hope that our research may also help shed light on clinical conditions of unresponsiveness such as attention disorders, dementia, schizophrenia, autism, and vegetative states.
The restorative value of sleep
How do specific patterns of activity in sleep lead to restoration of our cognition? How does sleep deprivation affect brain activity and behavior?
Sleep restores normal brain function and has a vital role for supporting cognition. Indeed, the most immediate unavoidable effect of sleep deprivation is cognitive impairment. Along this line, memory consolidation may be optimally performed offline when we are asleep or resting. We seek to identify the specific patterns of neuronal activity that have a causal role in such cognitive restoration, and study sleep’s restorative aspects in healthy individuals and patient populations.
Sleep as a window to functional brain networks in health and disease
Can spontaneous brain activity be used to reveal the brain’s functional organization?
Spontaneous brain activity and sleep in particular offer a unique window into the activity of functional networks that goes beyond the ability to follow elaborate tasks during wakefulness. Accumulating evidence suggests that many psychiatric and neurological health disorders manifest in spontaneous brain activity and during sleep in particular. By working closely with clinicians and by using parallel animal models, we will study how the individual sleep profile can be used to further our ability for diagnosis and prognosis in an array of brain disorders.
- Electrophysiology: single-unit activity, local field potentials, and EEG
- Auditory stimulation
- Functional MRI
- Intracranial recordings in neurosurgical patients
- Electrical stimulation
- Manipulation and recording of neuromodulatory activities