Abstract
Objective: A novel type of statistical time-frequency analysis was developed to elucidate changes of high-frequency EEG activity associated with epileptic spikes. Methods: The method uses the Gabor Transform and detects changes of power in comparison to background activity using t-statistics that are controlled by the false discovery rate (FDR) to correct type I error of multiple testing. The analysis was applied to EEGs recorded at 2000 Hz from three patients with mesial temporal lobe epilepsy. Results: Spike-related increase of high-frequency oscillations (HFOs) was clearly shown in the FDR-controlled t-spectra: it was most dramatic in spikes recorded from the hippocampus when the hippocampus was the seizure onset zone (SOZ). Depression of fast activity was observed immediately after the spikes, especially consistently in the discharges from the hippocampal SOZ. It corresponded to the slow wave part in case of spike-and-slow-wave complexes, but it was noted even in spikes without apparent slow waves. In one patient, a gradual increase of power above 200 Hz preceded spikes. Conclusions: FDR-controlled t-spectra clearly detected the spike-related changes of HFOs that were unclear in standard power spectra. Significance: We developed a promising tool to study the HFOs that may be closely linked to the pathophysiology of epileptogenesis.
| Original language | English |
|---|---|
| Pages (from-to) | 1070-1077 |
| Number of pages | 8 |
| Journal | Clinical Neurophysiology |
| Volume | 120 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - Jun 2009 |
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Keywords
- False discovery rate
- High-frequency
- Hippocampus
- Mesial temporal lobe epilepsy
- Spike
- Time-frequency analysis
ASJC Scopus subject areas
- Clinical Neurology
- Neurology
- Physiology (medical)
- Sensory Systems
Cite this
Detection of changes of high-frequency activity by statistical time-frequency analysis in epileptic spikes. / Kobayashi, Katsuhiro; Jacobs, Julia; Gotman, Jean.
In: Clinical Neurophysiology, Vol. 120, No. 6, 06.2009, p. 1070-1077.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Detection of changes of high-frequency activity by statistical time-frequency analysis in epileptic spikes
AU - Kobayashi, Katsuhiro
AU - Jacobs, Julia
AU - Gotman, Jean
PY - 2009/6
Y1 - 2009/6
N2 - Objective: A novel type of statistical time-frequency analysis was developed to elucidate changes of high-frequency EEG activity associated with epileptic spikes. Methods: The method uses the Gabor Transform and detects changes of power in comparison to background activity using t-statistics that are controlled by the false discovery rate (FDR) to correct type I error of multiple testing. The analysis was applied to EEGs recorded at 2000 Hz from three patients with mesial temporal lobe epilepsy. Results: Spike-related increase of high-frequency oscillations (HFOs) was clearly shown in the FDR-controlled t-spectra: it was most dramatic in spikes recorded from the hippocampus when the hippocampus was the seizure onset zone (SOZ). Depression of fast activity was observed immediately after the spikes, especially consistently in the discharges from the hippocampal SOZ. It corresponded to the slow wave part in case of spike-and-slow-wave complexes, but it was noted even in spikes without apparent slow waves. In one patient, a gradual increase of power above 200 Hz preceded spikes. Conclusions: FDR-controlled t-spectra clearly detected the spike-related changes of HFOs that were unclear in standard power spectra. Significance: We developed a promising tool to study the HFOs that may be closely linked to the pathophysiology of epileptogenesis.
AB - Objective: A novel type of statistical time-frequency analysis was developed to elucidate changes of high-frequency EEG activity associated with epileptic spikes. Methods: The method uses the Gabor Transform and detects changes of power in comparison to background activity using t-statistics that are controlled by the false discovery rate (FDR) to correct type I error of multiple testing. The analysis was applied to EEGs recorded at 2000 Hz from three patients with mesial temporal lobe epilepsy. Results: Spike-related increase of high-frequency oscillations (HFOs) was clearly shown in the FDR-controlled t-spectra: it was most dramatic in spikes recorded from the hippocampus when the hippocampus was the seizure onset zone (SOZ). Depression of fast activity was observed immediately after the spikes, especially consistently in the discharges from the hippocampal SOZ. It corresponded to the slow wave part in case of spike-and-slow-wave complexes, but it was noted even in spikes without apparent slow waves. In one patient, a gradual increase of power above 200 Hz preceded spikes. Conclusions: FDR-controlled t-spectra clearly detected the spike-related changes of HFOs that were unclear in standard power spectra. Significance: We developed a promising tool to study the HFOs that may be closely linked to the pathophysiology of epileptogenesis.
KW - False discovery rate
KW - High-frequency
KW - Hippocampus
KW - Mesial temporal lobe epilepsy
KW - Spike
KW - Time-frequency analysis
UR - http://www.scopus.com/inward/record.url?scp=67349148296&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=67349148296&partnerID=8YFLogxK
U2 - 10.1016/j.clinph.2009.03.020
DO - 10.1016/j.clinph.2009.03.020
M3 - Article
C2 - 19394892
AN - SCOPUS:67349148296
VL - 120
SP - 1070
EP - 1077
JO - Clinical Neurophysiology
JF - Clinical Neurophysiology
SN - 1388-2457
IS - 6
ER -