CLASSY (Closed Loop Auditory Stimulation in epilepsY) Version 1.0
Research type
Research Study
Full title
CLASSY (Closed Loop Auditory Stimulation in epilepsY)
IRAS ID
265694
Contact name
Khalid Hamandi
Contact email
Sponsor organisation
Cardiff and Vale UHB
Duration of Study in the UK
0 years, 2 months, 30 days
Research summary
Research Summary
This proposal looks at whether a new sleep aid (Closed Loop Auditory Stimulation, or CLAS) that has been well tested in healthy controls could have positive effects on sleep or memory in people with epilepsy. \n\nDuring deep sleep, brain waves form rolling waves recorded on an EEG (electroencephalogram). This is known as slow wave sleep. During this time, if a short ‘click’ noise is played at the peak of the brain wave, it slightly boosts the next wave. After people wake up from CLAS, they tend to have better short-term memory of things taught the night before. This project tests whether people with epilepsy can benefit from CLAS in the same way that healthy people do. Improving sleep and memory in people with epilepsy is particularly important, as poor sleep is a common seizure trigger, and people with epilepsy often report difficulties with sleep and short-term memory. \n\nWe will conduct a remote study to look at sleep and memory in outpatients with well-controlled seizures. Brain waves will be recorded through a portable EEG device (a specially developed head band) that can also play sounds during sleep. Participants will learn memory tasks before they get to bed, and their memory will be tested when they wake. We will do this over 2 nights, one with the click sounds the other without, to see if the sleep aid has improved short-term memory.
Summary of Results
This study was a pilot of a completely non-invasive auditory sleep aid, shown to safely modulate neural activity in healthy participants, undertaken in a cohort of patients with temporal lobe epilepsy. Closed Loop Auditory Stimulation (CLAS) has additionally been shown to enhance sleep and memory in healthy controls possibly by strengthening memory consolidation circuits, but as yet has not been used in these patient populations, although sleep and memory problems are often co-morbid. 15 outpatients (age 20-41) with temporal lobe epilepsy (TLE) and 22 (age 19-30) neurotypical controls performed memory tests before and after one night of sleep and wore a portable EEG band during sleep to record sleep parameters and deliver stimuli. Patients underwent two rounds of testing, with either 50(±5) decibels of CLAS delivered during stage 3 sleep, or no auditory stimulus. The study was carried out completely remotely due to the COVID pandemic of 2020, with EEG band delivered to participants at home and returned by them after each stage and at the end of their testing.
No seizures or serious adverse effects were reported on any night of the study, and the study was well-tolerated (87% participants completing). CLAS successfully modulated sleep in a sub-sample of patients only. These were correlated with individuals that had a higher baseline proportion of deep sleep, but this trend was not seen in healthy controls. Additionally, patients, but not controls, with the largest effect of CLASS showed high baseline memory scores, supporting the idea that CLAS in patients with epilepsy may be strongest in those with already relatively good sleep and memory and has limited effects in those with more pronounced sleep and memory issues, as circuits may be more fundamentally disrupted, or simply not be susceptible to change.REC name
Yorkshire & The Humber - Bradford Leeds Research Ethics Committee
REC reference
20/YH/0267
Date of REC Opinion
14 Sep 2020
REC opinion
Further Information Favourable Opinion