Spectral and spatial shifts of post-ictal slow waves in temporal lobe seizures

Lin Yang, Gregory Alan Worrell, Cindy Nelson, Benjamin Brinkmann, Bin He

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Temporal lobe seizures have a significant chance to induce impairment of normal brain functions. Even after the termination of ictal discharges, during the post-ictal period, loss of consciousness, decreased responsiveness or other cognitive dysfunctions can persist. Previous studies have found various anatomical and functional abnormalities accompanying temporal lobe seizures, including an abnormal elevation of cortical slow waves. Intracranial electroencephalography studies have shown a prominent increase of lower frequency components during and following seizures that impair (complex partial seizures) but not those that preserve (simple partial seizures) normal consciousness and responsiveness. However, due to the limited spatial coverage of intracranial electroencephalography, the investigation of cortical slow waves cannot be easily extended to the whole brain. In this study, we used scalp electroencephalography to study the spectral features and spatial distribution of post-ictal slow waves with comprehensive spatial coverage. We studied simple partial, complex partial and secondarily generalized seizures in 28 patients with temporal lobe seizures. We used dense-array electroencephalography and source imaging to reconstruct the post-ictal slow-wave distribution. In the studied cohort, we found that a 'global' spectral power shift to lower frequencies accompanied the increased severity of seizures. The delta spectral power relative to higher frequency bands was highest for secondarily generalized seizures, followed by complex partial seizures and lastly simple partial seizures. In addition to this 'global' spectral shift, we found a 'regional' spatial shift in slow-wave activity. Secondarily generalized seizures and complex partial seizures exhibited increased slow waves distributed to frontal areas with spread to contralateral temporal and parietal regions than in simple partial seizures. These results revealed that a widespread cortical network including temporal and fronto-parietal cortex is involved in abnormal slow-wave activity following temporal lobe seizures. The differential spectral and spatial shifts of post-ictal electroencephalography activity in simple partial, complex partial and secondarily generalized seizures suggest a possible connection between cortical slow waves and behavioural and cognitive changes in a human epilepsy model.

Original languageEnglish (US)
Pages (from-to)3134-3143
Number of pages10
JournalBrain
Volume135
Issue number10
DOIs
StatePublished - Oct 2012

Fingerprint

Temporal Lobe
Seizures
Stroke
Partial Epilepsy
Electroencephalography
Parietal Lobe
Waves
Spectrality
Unconsciousness
Brain
Scalp
Consciousness
Epilepsy

Keywords

  • consciousness
  • cortical slowing
  • post-ictal state
  • responsiveness
  • temporal lobe seizure

ASJC Scopus subject areas

  • Clinical Neurology
  • Arts and Humanities (miscellaneous)

Cite this

Spectral and spatial shifts of post-ictal slow waves in temporal lobe seizures. / Yang, Lin; Worrell, Gregory Alan; Nelson, Cindy; Brinkmann, Benjamin; He, Bin.

In: Brain, Vol. 135, No. 10, 10.2012, p. 3134-3143.

Research output: Contribution to journalArticle

Yang, Lin ; Worrell, Gregory Alan ; Nelson, Cindy ; Brinkmann, Benjamin ; He, Bin. / Spectral and spatial shifts of post-ictal slow waves in temporal lobe seizures. In: Brain. 2012 ; Vol. 135, No. 10. pp. 3134-3143.
@article{0bb7c4a65d1e4785b9d9dcdae5d5df02,
title = "Spectral and spatial shifts of post-ictal slow waves in temporal lobe seizures",
abstract = "Temporal lobe seizures have a significant chance to induce impairment of normal brain functions. Even after the termination of ictal discharges, during the post-ictal period, loss of consciousness, decreased responsiveness or other cognitive dysfunctions can persist. Previous studies have found various anatomical and functional abnormalities accompanying temporal lobe seizures, including an abnormal elevation of cortical slow waves. Intracranial electroencephalography studies have shown a prominent increase of lower frequency components during and following seizures that impair (complex partial seizures) but not those that preserve (simple partial seizures) normal consciousness and responsiveness. However, due to the limited spatial coverage of intracranial electroencephalography, the investigation of cortical slow waves cannot be easily extended to the whole brain. In this study, we used scalp electroencephalography to study the spectral features and spatial distribution of post-ictal slow waves with comprehensive spatial coverage. We studied simple partial, complex partial and secondarily generalized seizures in 28 patients with temporal lobe seizures. We used dense-array electroencephalography and source imaging to reconstruct the post-ictal slow-wave distribution. In the studied cohort, we found that a 'global' spectral power shift to lower frequencies accompanied the increased severity of seizures. The delta spectral power relative to higher frequency bands was highest for secondarily generalized seizures, followed by complex partial seizures and lastly simple partial seizures. In addition to this 'global' spectral shift, we found a 'regional' spatial shift in slow-wave activity. Secondarily generalized seizures and complex partial seizures exhibited increased slow waves distributed to frontal areas with spread to contralateral temporal and parietal regions than in simple partial seizures. These results revealed that a widespread cortical network including temporal and fronto-parietal cortex is involved in abnormal slow-wave activity following temporal lobe seizures. The differential spectral and spatial shifts of post-ictal electroencephalography activity in simple partial, complex partial and secondarily generalized seizures suggest a possible connection between cortical slow waves and behavioural and cognitive changes in a human epilepsy model.",
keywords = "consciousness, cortical slowing, post-ictal state, responsiveness, temporal lobe seizure",
author = "Lin Yang and Worrell, {Gregory Alan} and Cindy Nelson and Benjamin Brinkmann and Bin He",
year = "2012",
month = "10",
doi = "10.1093/brain/aws221",
language = "English (US)",
volume = "135",
pages = "3134--3143",
journal = "Brain",
issn = "0006-8950",
publisher = "Oxford University Press",
number = "10",

}

TY - JOUR

T1 - Spectral and spatial shifts of post-ictal slow waves in temporal lobe seizures

AU - Yang, Lin

AU - Worrell, Gregory Alan

AU - Nelson, Cindy

AU - Brinkmann, Benjamin

AU - He, Bin

PY - 2012/10

Y1 - 2012/10

N2 - Temporal lobe seizures have a significant chance to induce impairment of normal brain functions. Even after the termination of ictal discharges, during the post-ictal period, loss of consciousness, decreased responsiveness or other cognitive dysfunctions can persist. Previous studies have found various anatomical and functional abnormalities accompanying temporal lobe seizures, including an abnormal elevation of cortical slow waves. Intracranial electroencephalography studies have shown a prominent increase of lower frequency components during and following seizures that impair (complex partial seizures) but not those that preserve (simple partial seizures) normal consciousness and responsiveness. However, due to the limited spatial coverage of intracranial electroencephalography, the investigation of cortical slow waves cannot be easily extended to the whole brain. In this study, we used scalp electroencephalography to study the spectral features and spatial distribution of post-ictal slow waves with comprehensive spatial coverage. We studied simple partial, complex partial and secondarily generalized seizures in 28 patients with temporal lobe seizures. We used dense-array electroencephalography and source imaging to reconstruct the post-ictal slow-wave distribution. In the studied cohort, we found that a 'global' spectral power shift to lower frequencies accompanied the increased severity of seizures. The delta spectral power relative to higher frequency bands was highest for secondarily generalized seizures, followed by complex partial seizures and lastly simple partial seizures. In addition to this 'global' spectral shift, we found a 'regional' spatial shift in slow-wave activity. Secondarily generalized seizures and complex partial seizures exhibited increased slow waves distributed to frontal areas with spread to contralateral temporal and parietal regions than in simple partial seizures. These results revealed that a widespread cortical network including temporal and fronto-parietal cortex is involved in abnormal slow-wave activity following temporal lobe seizures. The differential spectral and spatial shifts of post-ictal electroencephalography activity in simple partial, complex partial and secondarily generalized seizures suggest a possible connection between cortical slow waves and behavioural and cognitive changes in a human epilepsy model.

AB - Temporal lobe seizures have a significant chance to induce impairment of normal brain functions. Even after the termination of ictal discharges, during the post-ictal period, loss of consciousness, decreased responsiveness or other cognitive dysfunctions can persist. Previous studies have found various anatomical and functional abnormalities accompanying temporal lobe seizures, including an abnormal elevation of cortical slow waves. Intracranial electroencephalography studies have shown a prominent increase of lower frequency components during and following seizures that impair (complex partial seizures) but not those that preserve (simple partial seizures) normal consciousness and responsiveness. However, due to the limited spatial coverage of intracranial electroencephalography, the investigation of cortical slow waves cannot be easily extended to the whole brain. In this study, we used scalp electroencephalography to study the spectral features and spatial distribution of post-ictal slow waves with comprehensive spatial coverage. We studied simple partial, complex partial and secondarily generalized seizures in 28 patients with temporal lobe seizures. We used dense-array electroencephalography and source imaging to reconstruct the post-ictal slow-wave distribution. In the studied cohort, we found that a 'global' spectral power shift to lower frequencies accompanied the increased severity of seizures. The delta spectral power relative to higher frequency bands was highest for secondarily generalized seizures, followed by complex partial seizures and lastly simple partial seizures. In addition to this 'global' spectral shift, we found a 'regional' spatial shift in slow-wave activity. Secondarily generalized seizures and complex partial seizures exhibited increased slow waves distributed to frontal areas with spread to contralateral temporal and parietal regions than in simple partial seizures. These results revealed that a widespread cortical network including temporal and fronto-parietal cortex is involved in abnormal slow-wave activity following temporal lobe seizures. The differential spectral and spatial shifts of post-ictal electroencephalography activity in simple partial, complex partial and secondarily generalized seizures suggest a possible connection between cortical slow waves and behavioural and cognitive changes in a human epilepsy model.

KW - consciousness

KW - cortical slowing

KW - post-ictal state

KW - responsiveness

KW - temporal lobe seizure

UR - http://www.scopus.com/inward/record.url?scp=84867738033&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84867738033&partnerID=8YFLogxK

U2 - 10.1093/brain/aws221

DO - 10.1093/brain/aws221

M3 - Article

C2 - 22923634

AN - SCOPUS:84867738033

VL - 135

SP - 3134

EP - 3143

JO - Brain

JF - Brain

SN - 0006-8950

IS - 10

ER -