A5031116162- EEG and Brain-Computer Interfaces
- Functional Brain Connectivity Studies
- Neural dynamics and brain function
- Sleep and Wakefulness Research
- Traumatic Brain Injury Research
- Transcranial Magnetic Stimulation Studies
- Traumatic Brain Injury and Neurovascular Disturbances
- Psychosomatic Disorders and Their Treatments
- Neural and Behavioral Psychology Studies
- Cardiac Arrest and Resuscitation
- Neuroscience and Neuropharmacology Research
- Advanced MRI Techniques and Applications
- Anesthesia and Sedative Agents
- Memory and Neural Mechanisms
- Photoreceptor and optogenetics research
- Stroke Rehabilitation and Recovery
- Neuroscience and Neural Engineering
- Advanced Neuroimaging Techniques and Applications
- Epilepsy research and treatment
- Heart Rate Variability and Autonomic Control
- Vestibular and auditory disorders
- Anesthesia and Neurotoxicity Research
- Neurological disorders and treatments
- Action Observation and Synchronization
- Paranormal Experiences and Beliefs
University of Milan
2016-2025
Canadian Institute for Advanced Research
2019-2025
Luigi Sacco Hospital
2016-2025
Don Carlo Gnocchi Foundation
2016-2025
University of Colombo
2024
University of Padua
2024
National Academies of Sciences, Engineering, and Medicine
2024
Società Italiana di Reumatologia
2024
ORCID
2024
University of Sussex
2024
When we fall asleep, consciousness fades yet the brain remains active. Why is this so? To investigate whether changes in cortical information transmission play a role, used transcranial magnetic stimulation together with high-density electroencephalography and asked how activation of one area (the premotor area) transmitted to rest brain. During quiet wakefulness, an initial response (∼15 milliseconds) at site was followed by sequence waves that moved connected areas several centimeters...
During much of sleep, virtually all cortical neurons undergo a slow oscillation (<1 Hz) in membrane potential, cycling from hyperpolarized state silence to depolarized intense firing. This is the fundamental cellular phenomenon that organizes other sleep rhythms such as spindles and waves. Using high-density electroencephalogram recordings humans, we show here each cycle traveling wave. Each wave originates at definite site travels over scalp an estimated speed 1.2-7.0 m/sec. Waves...
A theory-derived index of consciousness, which quantifies the complexity brain’s response to a stimulus, measures level consciousness in awake, sleeping, anesthetized, and brain-damaged subjects.
The frequency tuning of a system can be directly determined by perturbing it and observing the rate ensuing oscillations, so called natural frequency. This approach is used, for example, in physics, geology, also when one tunes musical instrument. In present study, we employ transcranial magnetic stimulation (TMS) to perturb set selected corticothalamic modules (Brodmann areas 19, 7, 6) high-density electroencephalogram measure their TMS consistently evoked dominant α-band oscillations (8–12...
By employing transcranial magnetic stimulation (TMS) in combination with high-density electroencephalography (EEG), we recently reported that cortical effective connectivity is disrupted during early non-rapid eye movement (NREM) sleep. This a time when subjects, if awakened, may report little or no conscious content. We hypothesized similar breakdown of underlie loss consciousness (LOC) induced by pharmacologic agents. Here, tested this hypothesis comparing EEG responses to TMS wakefulness...
Discerning the neural correlates of (un)consciousness sheds light on mechanisms underlying vegetative states.
Objective: High-density EEG during sleep represents a powerful new tool to reveal potential abnormalities in rhythm-generating mechanisms while avoiding confounding factors associated with waking activities. As first step this direction, the authors employed high-density explore whether rhythms differ between schizophrenia subjects, healthy individuals, and psychiatric control group history of depression. Method: Healthy comparison subjects (N=17), medicated patients (N=18), depression...
During much of sleep, cortical neurons undergo near-synchronous slow oscillation cycles in membrane potential, which give rise to the largest spontaneous waves observed normal electroencephalogram (EEG). Slow oscillations underlie characteristic features sleep EEG, such as and spindles. Here we show that, sleeping subjects, spindles can be triggered noninvasively reliably by transcranial magnetic stimulation (TMS). With appropriate parameters, each TMS pulse at <1 Hz evokes an individual,...
Patients surviving severe brain injury may regain consciousness without recovering their ability to understand, move and communicate. Recently, electrophysiological neuroimaging approaches, employing simple sensory stimulations or verbal commands, have proven useful in detecting higher order processing and, some cases, establishing degree of communication brain-injured subjects with impairment motor function. To complement these it would be develop methods detect recovery ways that do not...
Slow waves are the most prominent electroencephalographic (EEG) feature of sleep. These arise from synchronization slow oscillations in membrane potentials millions neurons. Scalp-level studies have indicated that not instantaneous events, but rather they travel across brain. Previous EEG were limited by poor spatial resolution EEGs and difficulty relating scalp to activity underlying cortex. Here we use high-density (hd-EEG) source modeling show individual spontaneous distinct cortical...
Validating objective, brain-based indices of consciousness in behaviorally unresponsive patients represents a challenge due to the impossibility obtaining independent evidence through subjective reports. Here we address this problem by first validating promising metric consciousness-the Perturbational Complexity Index (PCI)-in benchmark population who could confirm presence or absence reports, and then applying same index with disorders (DOCs).The encompassed 150 healthy controls...
Study Objectives:The mechanisms responsible for the homeostatic decrease of slow-wave activity (SWA, defined in this study as electroencephalogram [EEG] power between 0.5 and 4.0 Hz) during sleep are unknown. In agreement with a recent hypothesis, first 3 companion papers, large-scale computer simulations sleeping thalamocortical system showed that cortical synaptic strength is sufficient to account decline SWA. model, reduction SWA was accompanied by decreased incidence high-amplitude slow...
The electrophysiological correlates of anesthetic sedation remain poorly understood. We used high-density electroencephalography (hd-EEG) and source modeling to investigate the cortical processes underlying propofol anesthesia compare them sleep. 256-channel EEG recordings in humans during anesthesia. Hospital operating room. 8 healthy subjects (4 males) N/A Initially, induced increases power from 12–25 Hz. Loss consciousness (LOC) was accompanied by appearance slow waves that resembled NREM...
Prolonged wakefulness is associated not only with obvious changes in the way we feel and perform but also well-known clinical effects, such as increased susceptibility to seizures, hallucinations, relief of depressive symptoms. These effects suggest that prolonged may be significant state cortical circuits. While recent animal experiments have reported a progressive increase excitability time awake, no conclusive evidence could gathered humans. In this study, combine transcranial magnetic...
Despite the absence of responsiveness during anesthesia, conscious experience may persist. However, reliable, easily acquirable and interpretable neurophysiological markers presence consciousness in unresponsive states are still missing. A promising marker is based on decay-rate power spectral density (PSD) resting EEG. We acquired electroencephalogram (EEG) three groups healthy participants (n = 5 each), before anesthesia induced by either xenon, propofol or ketamine. Dosage each anesthetic...
During non-rapid eye movement (NREM) sleep (stage N3), when consciousness fades, cortico-cortical interactions are impaired while neurons still active and reactive. Why is this? We compared evoked-potentials recorded during wakefulness NREM by means of time-frequency analysis phase-locking measures in 8 epileptic patients undergoing intra-cerebral stimulations/recordings for clinical evaluation. observed that, electrical stimulation triggers a chain deterministic phase-locked activations its...