Breakdown of Cortical Effective Connectivity During Sleep
Marcello Massimini, Fabio Ferrarelli, Reto Huber, Steve K. Esser, Harpreet Singh, Giulio Tononi
Science September 29, 2005 DOI: 10.1126/science.1117256 (opens in new tab) via OpenAlex
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Human participants |
| Intervention | Transcranial magnetic stimulation |
| Keywords | Wakefulness Neuroscience Sleep system call Electroencephalography Transcranial magnetic stimulation |
| Citations | 1,603 |
| Key findings | During non-rapid eye movement sleep, cortical activation does not propagate beyond the stimulation site, indicating a breakdown in effective connectivity that may underlie the loss of consciousness. |
Abstract
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, we used transcranial magnetic stimulation together with high-density electroencephalography and asked how the activation of one cortical area (the premotor area) is transmitted to the rest of the brain. During quiet wakefulness, an initial response (approximately 15 milliseconds) at the stimulation site was followed by a sequence of waves that moved to connected cortical areas several centimeters away. During non-rapid eye movement sleep, the initial response was stronger but was rapidly extinguished and did not propagate beyond the stimulation site. Thus, the fading of consciousness during certain stages of sleep may be related to a breakdown in cortical effective connectivity.