Arthur Le Coz
@arthurlecoz.bsky.social
PhD Candidate in the Dream Team | Paris Brain Institute | Exploring the brain signature and consequences of sleepiness and mental fatigue
11/ Bottom line:
IH with long sleep time isn’t marked by “bad sleep” but by paradoxically deep and structured sleep, paired with excessive daytime sleepiness.
⏰ It’s time to look beyond the night
→ into daytime arousal systems and brain function during wakefulness.
IH with long sleep time isn’t marked by “bad sleep” but by paradoxically deep and structured sleep, paired with excessive daytime sleepiness.
⏰ It’s time to look beyond the night
→ into daytime arousal systems and brain function during wakefulness.
May 28, 2025 at 12:14 PM
11/ Bottom line:
IH with long sleep time isn’t marked by “bad sleep” but by paradoxically deep and structured sleep, paired with excessive daytime sleepiness.
⏰ It’s time to look beyond the night
→ into daytime arousal systems and brain function during wakefulness.
IH with long sleep time isn’t marked by “bad sleep” but by paradoxically deep and structured sleep, paired with excessive daytime sleepiness.
⏰ It’s time to look beyond the night
→ into daytime arousal systems and brain function during wakefulness.
10/ Can we use this info for diagnosis?
Using just one night of EEG, our model classified IH vs. controls with an AUC of 0.74 🎯
Still far from perfect, but it’s a step toward more objective, EEG-based diagnostics.
Using just one night of EEG, our model classified IH vs. controls with an AUC of 0.74 🎯
Still far from perfect, but it’s a step toward more objective, EEG-based diagnostics.
May 28, 2025 at 12:14 PM
10/ Can we use this info for diagnosis?
Using just one night of EEG, our model classified IH vs. controls with an AUC of 0.74 🎯
Still far from perfect, but it’s a step toward more objective, EEG-based diagnostics.
Using just one night of EEG, our model classified IH vs. controls with an AUC of 0.74 🎯
Still far from perfect, but it’s a step toward more objective, EEG-based diagnostics.
8/ We also explored slow wave activity.
💡 IH patients showed increased slow wave density during N3 despite no change in overall delta power.
This implies that global spectral analyses may miss subtle but meaningful changes in sleep microarchitecture.
💡 IH patients showed increased slow wave density during N3 despite no change in overall delta power.
This implies that global spectral analyses may miss subtle but meaningful changes in sleep microarchitecture.
May 28, 2025 at 12:14 PM
8/ We also explored slow wave activity.
💡 IH patients showed increased slow wave density during N3 despite no change in overall delta power.
This implies that global spectral analyses may miss subtle but meaningful changes in sleep microarchitecture.
💡 IH patients showed increased slow wave density during N3 despite no change in overall delta power.
This implies that global spectral analyses may miss subtle but meaningful changes in sleep microarchitecture.
7/ These changes were not mirrored by infraslow modulations of sigma power
📉 suggesting that while local sleep dynamics are altered, global regulatory rhythms (like those influenced by noradrenaline) may stay intact.
📉 suggesting that while local sleep dynamics are altered, global regulatory rhythms (like those influenced by noradrenaline) may stay intact.
May 28, 2025 at 12:14 PM
7/ These changes were not mirrored by infraslow modulations of sigma power
📉 suggesting that while local sleep dynamics are altered, global regulatory rhythms (like those influenced by noradrenaline) may stay intact.
📉 suggesting that while local sleep dynamics are altered, global regulatory rhythms (like those influenced by noradrenaline) may stay intact.
6/ Zooming into the microstructure 🔬
📈 IH patients had more sigma power & higher spindle density
🧠 Spindles were more clustered, pointing to over-stabilized thalamocortical networks
→ This might underlie severe sleep inertia and reduced responsiveness to stimuli.
📈 IH patients had more sigma power & higher spindle density
🧠 Spindles were more clustered, pointing to over-stabilized thalamocortical networks
→ This might underlie severe sleep inertia and reduced responsiveness to stimuli.
May 28, 2025 at 12:14 PM
6/ Zooming into the microstructure 🔬
📈 IH patients had more sigma power & higher spindle density
🧠 Spindles were more clustered, pointing to over-stabilized thalamocortical networks
→ This might underlie severe sleep inertia and reduced responsiveness to stimuli.
📈 IH patients had more sigma power & higher spindle density
🧠 Spindles were more clustered, pointing to over-stabilized thalamocortical networks
→ This might underlie severe sleep inertia and reduced responsiveness to stimuli.
4/ But sleep isn’t just sub-stages—sleep is a graded and dynamic process!
So, we turned to the analysis of hypnodensity 📊:
IH showed more mixed wake/N1 epochs, especially during intra-sleep awakenings.
⚠️ Are these a marker of sleep intrusions into wakefulness and difficulty fully waking up?
So, we turned to the analysis of hypnodensity 📊:
IH showed more mixed wake/N1 epochs, especially during intra-sleep awakenings.
⚠️ Are these a marker of sleep intrusions into wakefulness and difficulty fully waking up?
May 28, 2025 at 12:14 PM
4/ But sleep isn’t just sub-stages—sleep is a graded and dynamic process!
So, we turned to the analysis of hypnodensity 📊:
IH showed more mixed wake/N1 epochs, especially during intra-sleep awakenings.
⚠️ Are these a marker of sleep intrusions into wakefulness and difficulty fully waking up?
So, we turned to the analysis of hypnodensity 📊:
IH showed more mixed wake/N1 epochs, especially during intra-sleep awakenings.
⚠️ Are these a marker of sleep intrusions into wakefulness and difficulty fully waking up?
3/ First, macrostructure:
🛌 IH participants had more N3 and higher sleep efficiency
😴 Less REM and reduced wake after sleep onset
📉 These results might partly reflect the way sleep tests are run (e.g., waking at 6:30am for MSLT → less REM at the end of the night)
🛌 IH participants had more N3 and higher sleep efficiency
😴 Less REM and reduced wake after sleep onset
📉 These results might partly reflect the way sleep tests are run (e.g., waking at 6:30am for MSLT → less REM at the end of the night)
May 28, 2025 at 12:14 PM
3/ First, macrostructure:
🛌 IH participants had more N3 and higher sleep efficiency
😴 Less REM and reduced wake after sleep onset
📉 These results might partly reflect the way sleep tests are run (e.g., waking at 6:30am for MSLT → less REM at the end of the night)
🛌 IH participants had more N3 and higher sleep efficiency
😴 Less REM and reduced wake after sleep onset
📉 These results might partly reflect the way sleep tests are run (e.g., waking at 6:30am for MSLT → less REM at the end of the night)
🚨New preprint out! 🚨
We investigated the EEG signatures of Idiopathic Hypersomnia (IH) with long sleep time using fine-grained EEG analysis in PSG recordings.
Here’s what we found 👇
www.biorxiv.org/content/10.1...
(Illustration from nicolasdecat.com)
(1/12)
We investigated the EEG signatures of Idiopathic Hypersomnia (IH) with long sleep time using fine-grained EEG analysis in PSG recordings.
Here’s what we found 👇
www.biorxiv.org/content/10.1...
(Illustration from nicolasdecat.com)
(1/12)
May 28, 2025 at 12:14 PM
🚨New preprint out! 🚨
We investigated the EEG signatures of Idiopathic Hypersomnia (IH) with long sleep time using fine-grained EEG analysis in PSG recordings.
Here’s what we found 👇
www.biorxiv.org/content/10.1...
(Illustration from nicolasdecat.com)
(1/12)
We investigated the EEG signatures of Idiopathic Hypersomnia (IH) with long sleep time using fine-grained EEG analysis in PSG recordings.
Here’s what we found 👇
www.biorxiv.org/content/10.1...
(Illustration from nicolasdecat.com)
(1/12)