4.7 Article

Interictal spikes with and without high-frequency oscillation have different single-neuron correlates

Journal

BRAIN
Volume 144, Issue -, Pages 3078-3088

Publisher

OXFORD UNIV PRESS
DOI: 10.1093/brain/awab288

Keywords

single unit; interictal spikes; high-frequency oscillations; epilepsy; intracranial EEG

Funding

  1. German Research Foundation (DFG) [JA 1725/4-1, KU 4060/1-1]
  2. Berta-OttensteinProgramme, Faculty of Medicine, University of Freiburg
  3. Federal Ministry of Education and Research (BMBF) [01GQ1705A]
  4. National Science Foundation (NSF) [BCS1724243]
  5. NIH/NINDS [U01 NS113198-01]
  6. Fraunhofer Society

Ask authors/readers for more resources

The study shows that HFO-IEDs and non-HFO-IEDs have different single-unit correlates. Single-unit firing rates are higher in HFO-IEDs compared to non-HFO-IEDs, with a pronounced pre-peak increase in firing in HFO-IEDs. Moreover, most cells exhibit higher rates during HFO-IEDs, suggesting a distinct subset of neurons prefer this IED subtype.
Interictal epileptiform discharges (IEDs) are a widely used biomarker in patients with epilepsy but lack specificity. It has been proposed that there are truly epileptogenic and less pathological or even protective IEDs. Recent studies suggest that highly pathological IEDs are characterized by high-frequency oscillations (HFOs). Here, we aimed to dissect these 'HFO-IEDs' at the single-neuron level, hypothesizing that the underlying mechanisms are distinct from 'non-HFO-IEDs'. Analysing hybrid depth electrode recordings from patients with temporal lobe epilepsy, we found that single-unit firing rates were higher in HFO- than in non-HFO-IEDs. HFO-IEDs were characterized by a pronounced pre-peak increase in firing, which coincided with the preferential occurrence of HFOs, whereas in non-HFOIEDs, there was only a mild pre-peak increase followed by a post-peak suppression. Comparing each unit's firing during HFO-IEDs to its baseline activity, we found many neurons with a significant increase during the HFO component or ascending part, but almost none with a decrease. No such imbalance was observed during non-HFO-IEDs. Finally, comparing each unit's firing directly between HFO- and non-HFO-IEDs, we found that most cells had higher rates during HFO-IEDs and, moreover, identified a distinct subset of neurons with a significant preference for this IED subtype. In summary, our study reveals that HFO- and non-HFO-IEDs have different single-unit correlates. In HFO-IEDs, many neurons are moderately activated, and some participate selectively, suggesting that both types of increased firing contribute to highly pathological IEDs.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available