Skip to main content
OpenTrials
Completed

NCT Number: NCT03090711

Sleep as a Model to Understand and Manipulate Cortical Activity in Order to Promote Functional Recovery After Stroke

Brain functions are supported by multiple cell types, including neuronal and non-neuronal cells that are connected into complex networks. When the connectivity between those cells is altered or disrupted, the functioning of the brain is impaired. In stroke, the interruption of blood supply to the neural circuits results in connectivity damage and permanent disabilities. Experimental evidence suggests that some types of brain state, including sleep, can protect brain tissue from stroke and "repair" the damaged circuits. This project will investigate the neuronal mechanism underlying the protective effect of sleep on brain connectivity and network activity. To this end, the investigators will use a collection of state-of-the-art technologies including high-density electroencephalography (hd-EEG), transcranial magnetic stimulation (TMS) and transcranial alternating current stimulation (tACS). Perspectives include a better understanding of the causes and consequences of the perturbed electrical activity of the brain during sleep in stroke patients.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Hemispatial Neglect Nervous System Diseases Neurobehavioral Manifestations Neurologic Manifestations Pathological Conditions, Signs and Symptoms Perceptual Disorders Signs and Symptoms

Age range

18 year–80 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Department of Neurology, Inselspital, Bern University Hospital

Bern, 3010, Switzerland

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Informed consent as documented by signature
  • Age between 18 and 80 years
  • First-ever right-sided stroke
  • Normal or corrected to normal vision
  • Demonstration of left hemispatial neglect (after a right-hemispheric brain lesion) found in a comprehensive neuropsychological test battery and clinical assessment
  • At least 3 weeks post-stroke

Exclusion criteria

  • Concomitant neurodegenerative diseases
  • Psychiatric diseases
  • Decompressive craniectomy
  • History of documented sleep disorders in the medical record (e.g. insomnia, hypersomnia, rem-sleep behaviour disorder)
  • Epileptic seizures
  • Implanted medical devices (e.g.: pacemakers, cochlear implants, implanted neurostimulators)
  • Presence of metal in the region of the head (excluding fixed dental implants such as tooth fillings or fixed dental braces)
  • Medication with drugs possibly lowering the seizure threshold
  • Alcohol or drug abuse
  • Inability to follow the procedures of the study
  • For female patients: in order to participate in the study, female patients in reproductive age need to take a pregnancy test (a standard urine pregnancy test will be provided).

Treatment and study plan

Transcranial Magnetic Stimulation (TMS)

Device

The investigators recently showed that the repeated application of the so-called continuous theta burst protocol (cTBS) over the contralesional hemisphere resulted in a long-standing improvement of visual hemineglect (Cazzoli et al., 2012). The cTBS protocol was developed by Huang et al. (Huang et al., 2005) and modified by the investigators' group (Nyffeler et al., 2006). TBS protocol consists of a burst of 3 pulses at a frequency of 30 Hz, repeated at 6 Hz. One continuous train includes 801 pulses, the duration of one cTBS train is 44 seconds.

transcranial alternating current stimulation (tACS)

Device

TACS stimulation involves two electrodes placed on either side of the desired site of cortical stimulation. The mode of stimulation used in this experiment is identical to previous studies using tACS in sleep ( Marshall et al., 2006; Prehn-Kristensen et al., 2014 ). Stimulation follows a sinusoidal pattern from 0 to 260 μA. This pattern is delivered at 0.75 Hz and is repeated for 225 cycles; a total of 5 minutes of stimulation. This 5 minute pattern is again repeated 5 times, with a minute of no stimulation between each; thus for a total of 30 minutes.

Sham Transcranial Magnetic Stimulation (TMS)

Device

Sham coil will be used to exclude possible nonspecific effects of the TMS. The sham coil is shielded i.e., the magnetic field output is weakened and therefore insufficiently powerful to stimulate the cortex.

Sham transcranial alternating current stimulation (tACS)

Device

Sham stimulation will be used to exclude possible nonspecific effects of the tACS. Sham tACS stimulation will involve actual stimulation for the first 30 seconds of the ramp-up period (stimulation power is gradually increased until its final level), and then immediately gradually decreased until zero (without the intermediate 4 minutes of actual stimulation). This procedure will be repeated 5 times every 6 minutes and shall induce similar cutaneous sensations as real stimulation.

Primary outcomes

  1. Change from baseline in visual exploration and sleep parameters and the effect of cTBS

    Time frame: Day 3

    Relationship of visual exploration (mean cumulative fixation duration) to sleep parameters (slow wave activity and spindles) from the baseline to post-cTBS sleep.

  2. Change from baseline in the effect of tACS on visual exploration

    Time frame: Day 2

    Group comparison of visual exploration task (mean cumulative fixation duration) between real and sham tACS.

Secondary outcomes

  1. The effect of cTBS on sleep

    Time frame: Day 1 to 3

    Relationship between baseline sleep parameters (slow wave activity and spindles) and effectiveness of cTBS.

  2. The effect of tACS on sleep

    Time frame: Day 1 to 2

    Change in sleep architecture (REM and NREM sleep) between tACS and sham stimulation.

Sponsors and collaborators

Lead sponsor

Insel Gruppe AG, University Hospital Bern

Other

Registry information

Official study title

Sleep as a Model to Understand and Manipulate Cortical Activity in Order to Promote Neuroplasticity and Functional Recovery After Stroke

Acronym: SSS

Important dates

Study start
2017
Primary completion
2020
Study completion
2020
First posted
Mar 27, 2017
Registry last updated
May 3, 2021

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.