Objective EEG Bed Side Assessment of Impaired Conscious Awareness in Epilepsy

NCT04799795 | Completed

• 1 other identifier: D 558/17
• Study Type: observational
• Target: 49
• Locations: 1 country
• Sites: 1

Brief Summary

In this project EEG recordings between healthy participants and those with a diagnosed Absence-epilepsy will be compared. The investigators suggest differences in EEG microstate analysis and neuropsychological parameters related to interictal cognitive impairment in these patients. This projects goal is to derive an EEG-based measure of conscious awareness.

Conditions

Epilepsy, Absence

Keywords

interictal activity; impaired consciousness; absence epilepsy

Outcome Measures

Primary Outcomes (4)

• temporal integration changes according to different sleep states

  The investigators develop an EEG-based measure of impaired conscious awareness based on wakefulness and deepening sleep stages which will serve as a model for increasingly impaired conscious awareness. By performing a microstate analysis on EEG data, the investigators hypothesize a decrease of the temporal integration, a prerequisite for conscious awareness, of the EEG gradually from wakefulness to deep sleep.

  3 years

• temporal integration changes in interictal EEG

  The investigators apply the aforementioned analysis (leading to Outcome 1) on interictal EEG recordings obtained from patients with diagnosed absence epilepsy. The investigators hypothesize a reduced temporal integration in epilepsies with reduced consciousness.

  3 years

• graph modularity changes according to different sleep states

  The investigators will calculate the EEG-based functional connectivity and graph modularity for each sleep state. The investigators hypothesize that during wakefulness, graph modularity will be lower than during the descent to sleep.

  3 years

• graph modularity changes in interictal EEG

  The investigators will calculate the EEG-based functional connectivity and graph modularity for the absence epilepsy condition. The investigators hypothesize that impaired consciousness will be reflected in lower graph modularity compared to healthy subjects.

  3 years

Secondary Outcomes (1)

• EEG based measures (Outcome 4) correlate with

  3 years

Study Arms (2)

healthy subjects

Age-matched healthy participants will be recruited via flyers at public education facilities and online advertisement. Participants need to be healthy and without central nervous system disorders and substance abuse. The investigators will also exclude pregnant women from the experiment.

patients with absence epilepsy

Apart from the diagnosis of epilepsy, patients need to be of good health and without central nervous system disorders and substance abuse. The investigators will also exclude pregnant women from the experiment.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with diagnosed absence epilepsy at least 18 years old; age-matched controls.

You may qualify if:

• age minimum 18 years
• diagnosis of (absence) epilepsy // healthy age-matched controls
• being of good health (besides epilepsy in the case group)

You may not qualify if:

• central nervous system disorders (besides epilepsy in the case group)
• substance abuse
• pregnancy

Sponsors & Collaborators

• University Hospital Schleswig-Holstein: lead
• German Research Foundation: collaborator

Study Sites (1)

Department of Neurology

Kiel, 24105, Germany

Location

Related Publications (10)

• Brodbeck V, Kuhn A, von Wegner F, Morzelewski A, Tagliazucchi E, Borisov S, Michel CM, Laufs H. EEG microstates of wakefulness and NREM sleep. Neuroimage. 2012 Sep;62(3):2129-39. doi: 10.1016/j.neuroimage.2012.05.060. Epub 2012 May 30.

  PMID: 22658975 BACKGROUND

• Haimovici A, Tagliazucchi E, Balenzuela P, Laufs H. On wakefulness fluctuations as a source of BOLD functional connectivity dynamics. Sci Rep. 2017 Jul 19;7(1):5908. doi: 10.1038/s41598-017-06389-4.

  PMID: 28724928 BACKGROUND

• Kuhn A, Brodbeck V, Tagliazucchi E, Morzelewski A, von Wegner F, Laufs H. Narcoleptic Patients Show Fragmented EEG-Microstructure During Early NREM Sleep. Brain Topogr. 2015 Jul;28(4):619-35. doi: 10.1007/s10548-014-0387-1. Epub 2014 Aug 29.

  PMID: 25168255 BACKGROUND

• Laufs H, Rodionov R, Thornton R, Duncan JS, Lemieux L, Tagliazucchi E. Altered FMRI connectivity dynamics in temporal lobe epilepsy might explain seizure semiology. Front Neurol. 2014 Sep 11;5:175. doi: 10.3389/fneur.2014.00175. eCollection 2014.

  PMID: 25309503 BACKGROUND

• Tagliazucchi E, Crossley N, Bullmore ET, Laufs H. Deep sleep divides the cortex into opposite modes of anatomical-functional coupling. Brain Struct Funct. 2016 Nov;221(8):4221-4234. doi: 10.1007/s00429-015-1162-0. Epub 2015 Dec 9.

  PMID: 26650048 BACKGROUND

• Tagliazucchi E, Laufs H. Decoding wakefulness levels from typical fMRI resting-state data reveals reliable drifts between wakefulness and sleep. Neuron. 2014 May 7;82(3):695-708. doi: 10.1016/j.neuron.2014.03.020.

  PMID: 24811386 BACKGROUND

• Tagliazucchi E, Roseman L, Kaelen M, Orban C, Muthukumaraswamy SD, Murphy K, Laufs H, Leech R, McGonigle J, Crossley N, Bullmore E, Williams T, Bolstridge M, Feilding A, Nutt DJ, Carhart-Harris R. Increased Global Functional Connectivity Correlates with LSD-Induced Ego Dissolution. Curr Biol. 2016 Apr 25;26(8):1043-50. doi: 10.1016/j.cub.2016.02.010. Epub 2016 Apr 13.

  PMID: 27085214 BACKGROUND

• Tagliazucchi E, von Wegner F, Morzelewski A, Brodbeck V, Borisov S, Jahnke K, Laufs H. Large-scale brain functional modularity is reflected in slow electroencephalographic rhythms across the human non-rapid eye movement sleep cycle. Neuroimage. 2013 Apr 15;70:327-39. doi: 10.1016/j.neuroimage.2012.12.073. Epub 2013 Jan 9.

  PMID: 23313420 BACKGROUND

• Tagliazucchi E, von Wegner F, Morzelewski A, Brodbeck V, Jahnke K, Laufs H. Breakdown of long-range temporal dependence in default mode and attention networks during deep sleep. Proc Natl Acad Sci U S A. 2013 Sep 17;110(38):15419-24. doi: 10.1073/pnas.1312848110. Epub 2013 Sep 3.

  PMID: 24003146 BACKGROUND

• von Wegner F, Tagliazucchi E, Laufs H. Information-theoretical analysis of resting state EEG microstate sequences - non-Markovianity, non-stationarity and periodicities. Neuroimage. 2017 Sep;158:99-111. doi: 10.1016/j.neuroimage.2017.06.062. Epub 2017 Jun 30.

  PMID: 28673879 BACKGROUND

MeSH Terms

Conditions

Epilepsy, Absence

Condition Hierarchy (Ancestors)

Epilepsy, Generalized; Epilepsy; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epileptic Syndromes

Study Officials

• Inken Toedt, Dr. phil. Dipl.-Psych.

  University Hospital Schleswig-Holstein, Kiel

  PRINCIPAL INVESTIGATOR

• Helmut Laufs, PD Dr. med.

  University Hospital Schleswig-Holstein, Kiel

  STUDY DIRECTOR

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Scientist in Neuroimaging

Study Record Dates

• First Submitted: March 12, 2021
• First Posted: March 16, 2021
• Study Start: October 1, 2021
• Primary Completion: May 24, 2025
• Study Completion: May 24, 2025
• Last Updated: July 8, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

DE (1)