Neural Noise

iEEG and brain activity linked to impaired consciousness in frontal lobe seizures

2 min read

  • Intracranial EEG links brain activity to impaired consciousness in frontal lobe seizures.1
  • The work informs clinical neurophysiology and consciousness decoding, with relevance for epilepsy and ICU monitoring.1 1

Gardner updates

  • Neurology reported a relationship between brain activity (iEEG) and impaired consciousness in frontal lobe seizures, with relevance for clinical neurophysiology and consciousness decoding. 1

Weekly enrichment (2026-07-20)

  • The underlying study is Salardini, Vaddiparti, Kumar, et al., “Relationship Between Brain Activity and Impaired Consciousness in Frontal Lobe Seizures,” Neurology 2025;105(6):e213965 (DOI 10.1212/WNL.0000000000213965).2
  • It was a retrospective, multicenter analysis of intracranial EEG (icEEG) recordings pooled from three epilepsy centers, covering 65 frontal lobe seizures in 30 patients (mean age 27.7 years, 43% female).2 3
  • Seizures were classified by blinded video review into focal preserved consciousness (FPC, n=24), focal impaired consciousness (FIC, n=27) and focal to bilateral tonic-clonic (FBTC, n=14), and icEEG power change from preictal baseline was computed across delta, theta, alpha, beta and gamma bands.4
  • FPC seizures showed roughly 40% icEEG power increases confined mainly to the frontal lobe of seizure onset, with relatively small changes in other cortical regions.2 3
  • FIC seizures showed about 50% power increases; this was not significantly different from FPC in the frontal lobe of onset (p = 0.519, 95% CI −25.8 to 50.4) but was significantly greater in other widespread cortical regions (p < 0.001, 95% CI 14.1–45.3).2 3
  • Crucially, the widespread FIC power increases spanned not only slow-wave frequencies but also faster bands, with gamma power significantly higher than in focal-aware seizures — a pattern distinct from temporal lobe epilepsy, where impaired consciousness is tied to cortical slow-wave activity.2 3
  • FBTC seizures produced much larger, broadband, whole-cortex power increases of approximately 600%, significantly greater than FIC seizures both at the frontal onset zone and in other regions (p < 0.001, 95% CI 330.1–781.9 and 375.3–818.2).2 3
  • The authors argue that different focal seizure types impair consciousness through distinct physiologic mechanisms affecting widespread cortex, an insight that could inform icEEG biomarkers and future neuromodulation aimed at preserving consciousness during seizures.2 4

Footnotes

  1. https://news.google.com/rss/articles/CBMiakFVX3lxTE8tNk81WXNka2JLM0NwRUVoelYybk9TYjhFTWlud2ZnR3Jjcy1TT2VDMUJrMzRhUHc5UjlpRnZwLTQ2N3BfdWRrUzVGSEk2SURaQ2VqY1oxUGVCb1hXbjZRUXhWUkNTcW1rSkE?oc=5 ↩ ↩2 ↩3 ↩4

  2. https://doi.org/10.1212/wnl.0000000000213965 ↩ ↩2 ↩3 ↩4 ↩5 ↩6 ↩7

  3. https://www.biorxiv.org/content/10.1101/2024.09.20.614207v1.full-text ↩ ↩2 ↩3 ↩4 ↩5

  4. https://www.clinician.com/articles/intracranial-eeg-activity-and-consciousness-in-frontal-lobe-seizures ↩ ↩2

Graph View