Sleep & brain signals: what science reveals
IMpact of Sleep on health
How is sleep architecture organized?
Sleep is essential for maintaining optimal physical and mental health, and that is why we spend about one-third of our life either sleeping or trying to fall asleep.
It is determinant for:
- Memory and learning mechanisms
- Vigilance
- Hormonal regulation
- Metabolic regulation
- Immune system stimulation
Adults should get at least 7 hours of sleep per night.
Sleep architecture is organized into two main phases :
- Non Rapid Eye Movement (NREM) sleep (≈75% of total sleep) .
- Rapid Eye Movement (REM) sleep (≈25% of total sleep, most present in the second part of the night), known as dreamy sleep.
The structure and patterns of sleep stages can be analysed using polysomnography (EEG and EMG).
SLEEP DISORDERS, A WORLDWIDE BURDEN
Origin of sleep disorders
These issues can result from:
- External factors (e.g., stress, noise)
- Central or pathological origins (e.g., narcolepsy, sleep apnea)
- Central nervous system disorders comorbidities (e.g., Alzheimer’s disease, Parkinson’s disease)
Studying sleep is therefore a major public health priority.
What about brain activity?
Brain electrical activity and sleep have been conserved throughout species evolution. In rodents, sleep is particularly well described and similar to human sleep (with NREM and REM sleep).
Therefore, EEG/EMG recordings constitute powerful translational tools to study sleep, providing valuable insights into the mechanisms underlying sleep stages and related pathologies.
Sleep Impairment in Parkinson's
One of the most prominent symptoms of PD is REM sleep behaviour disorder (RBD), in which patients physically enact their dreams, sometimes with violent movements.
RBD is considered one of the strongest early clinical markers of PD: more than 80% of patients suffering RBD develop PD within the following decade.
Studying sleep in this context may therefore help identify early biomarkers of the disease, prior to the onset of neurodegeneration.
SOURCES
Sources : cdc.gov/sleep/about/index.html Institut national du sommeil & de la vigilance
Bollu (2024)
Poon (2021), Chattu (2018)
Barrillot (2018), Buzsaki (2013), Watson (2015)
Parkinson.org
Manon Villalba,PhD
Research Engineer at SynapCell
Manon Villalba, PhD is a Research Engineer at SynapCell, specializing in electrophysiology and pharmacology for preclinical CNS research. She contributes to the development of advanced EEG-based approaches to characterize brain activity, neural dynamics, and drug-induced effects in translational models. With expertise in sleep research, EEG signal processing, and neurophysiology, she supports the acquisition and analysis of multichannel brain signals. At SynapCell, she contributes to the development of robust, translatable EEG-based biomarkers supporting CNS drug discovery.
Antoine Paccard, MSc
Data Unit Manager at SynapCell,
Antoine Paccard, MSc is Data Unit Manager at SynapCell, specializing in the management and analysis of complex electrophysiological datasets for preclinical CNS research. He leads data-driven activities including EEG processing, quality control, and interpretation in translational animal models. Working at the interface of neuroscience and data science, he develops robust analytical pipelines enabling objective assessment of drug effects on brain function. At SynapCell, he ensures data reliability, scientific rigor, and the translational relevance of preclinical EEG studies supporting decision-making.