An interventional study of Closed-Loop/Open-Loop Acoustic Stimulation (CLAS) in NREM Parasomnias, Sleepwalking and Sleep Terrors, sponsored by Anna Castelnovo. Not yet recruiting at 1 site in Switzerland. Open to participants aged 6 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by Anna Castelnovo · Not applicable, Interventional, and Basic science
Disorders of Arousal (DoA)-such as sleepwalking, sleep terrors, and confusional arousals-are common sleep problems that happen during deep, non-dreaming sleep. Researchers do not fully understand what triggers these episodes or how to influence them.
This study tests whether playing soft sounds during sleep can help researchers learn more about, and possibly induce or modulate, these episodes under safe, supervised conditions. Participants with DoA will spend two nights in the sleep laboratory, with painless sensors placed on the scalp and body (similar to a regular sleep study). On one night, no sound is played. On the other night, soft sounds are played during deep sleep. The order of the two nights is decided randomly for each participant.
A small group of healthy volunteers without DoA will also take part, undergoing a single night with sound stimulation, to help researchers understand whether the sounds affect everyone the same way or specifically trigger episodes in people with DoA.
A subgroup of participants with DoA will also take part in a later, exploratory step in which the sound is triggered automatically, in real time, based on brain activity patterns.
The sounds used are very quiet, similar in volume to normal conversation, and stimulation is stopped right away if a participant shows any discomfort. The goal of this research is to better understand what triggers Disorders of Arousal, and to test whether sound-based stimulation could one day help study or manage this condition.
Disorders of Arousal (DoA)-including sleepwalking, sleep terrors, and confusional arousals-are NREM parasomnias whose underlying neurophysiological triggers remain poorly understood. A growing body of evidence suggests that DoA episodes do not emerge randomly from sleep but arise from identifiable pre-episode EEG states characterized by increased slow-wave activity and reduced cortical activation, consistent with a transient state of arousal instability. Closed-loop acoustic stimulation (CLAS) is an established, non-invasive method for probing and modulating NREM sleep physiology, but has not previously been applied in the specific context of NREM parasomnias.
This study investigates whether controlled acoustic stimulation, initially delivered with randomized timing and subsequently in a real-time, EEG-triggered closed-loop fashion, can reliably elicit or modulate DoA episodes under supervised laboratory conditions. A small group of healthy volunteers undergoes a single stimulation night to estimate the specificity of stimulation-elicited motor responses, helping distinguish genuine DoA vulnerability from a non-specific arousal response to sound.
The within-subject, randomized-order design in DoA participants allows each to serve as their own control, isolating the effect of acoustic stimulation from other sources of night-to-night variability. The exploratory closed-loop sub-study tests the technical feasibility of triggering stimulation based on real-time EEG markers of vulnerability, representing a first step toward future predictive or modulation-based approaches for this condition.
This study is part of a broader research programme on the neurobiological characterization of Disorders of Arousal; related observational components (including neuroimaging, neuropsychological assessment, and home monitoring) are registered separately.
This is the only study on the registry with Anna Castelnovo as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
For participants with Disorders of Arousal (DoA):
For healthy volunteers:
Exclusion Criteria (all participants):
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants with DoA (N=55) undergo overnight high-density EEG and video-polysomnography with no acoustic stimulation. Within-subject baseline condition; order relative to Arm 2 is randomized per participant.
The same DoA participants (N=55) undergo overnight high-density EEG and video-polysomnography with low-intensity open-loop acoustic stimulation delivered during slow-wave sleep; order relative to Arm 1 is randomized per participant. A subset of 10 participants additionally undergoes a later, exploratory real-time closed-loop stimulation sub-phase.
Device: Closed-Loop/Open-Loop Acoustic Stimulation (CLAS)
A separate group of healthy participants (N=5) undergoes a single overnight high-density EEG and video-polysomnography recording including open-loop acoustic stimulation during slow-wave sleep, to estimate the specificity of stimulation-elicited motor responses relative to the DoA group.
Device: Closed-Loop/Open-Loop Acoustic Stimulation (CLAS)
Brief, low-intensity auditory stimuli (pure tones or noise bursts, 50-70 dB SPL, approximately 1 second in duration) delivered via a standard speaker during confirmed slow-wave sleep (SWS). In the initial open-loop phase, stimuli are presented with randomized timing. In a later closed-loop sub-study, stimuli are triggered automatically in real time based on predefined EEG features, within randomized vulnerability versus refractory stimulation windows. Stimulation is immediately interrupted in the event of distress, full awakening, or any adverse reaction.
Number of DoA Episodes During the Stimulation Night Compared With the No-Stimulation Night
Number of video-polysomnographically confirmed Disorders of Arousal (DoA) episodes (sleepwalking, sleep terror, or confusional arousal), compared within-subject between the stimulation night and the no-stimulation (baseline) night.
Time frame: Assessed during the two laboratory overnight recordings (no-stimulation night and stimulation night), at least 48 hours apart, up to 6 weeks
Duration of DoA Episodes (Seconds): Stimulation Night vs. No-Stimulation Night
Mean duration (seconds) of video-polysomnographically confirmed DoA episodes, compared within-subject between the stimulation night and the no-stimulation (baseline) night.
Time frame: Assessed during the two laboratory overnight recordings (no-stimulation night and stimulation night), at least 48 hours apart, up to 6 weeks.
Proportion of Slow-Wave Sleep Epochs With Successful Stimulation Trigger (Percentage)
Percentage of detected slow-wave sleep epochs in which acoustic stimulation was successfully triggered within the predefined target window, during the stimulation night.
Time frame: Assessed during the stimulation-night overnight recording, up to 6 weeks.
Visual Analogue Scale (VAS) Rating of Perceived Discomfort Related to Acoustic Stimulation
Participant-rated discomfort attributable to acoustic stimulation, using a 0-10 visual analogue scale (0 = no discomfort, 10 = worst imaginable discomfort)
Time frame: Assessed the morning following the stimulation night, up to 6 weeks.
Arousal Index (EEG Arousals per Hour of Sleep): Stimulation Night vs. No-Stimulation Night
Arousal index (number of EEG-defined arousals per hour of total sleep time, scored per AASM criteria), compared between the stimulation night and the no-stimulation night.
Time frame: Assessed during both laboratory overnight recordings (no-stimulation night and stimulation night), up to 6 weeks.
Sleep Efficiency (Percentage): Stimulation Night vs. No-Stimulation Night
Sleep efficiency (percentage of time in bed spent asleep), derived from polysomnographic sleep staging, compared between the stimulation night and the no-stimulation night.
Time frame: Assessed during both laboratory overnight recordings (no-stimulation night and stimulation night), up to 6 weeks.
Proportion of DoA Episodes With Reported Conscious Experience: Spontaneous vs. Stimulation-Elicited Episodes
Percentage of DoA episodes associated with a reported conscious experience (recalled or unrecalled mental content, assessed via immediate post-episode interview), compared between spontaneous episodes (no-stimulation night) and stimulation-elicited episodes (stimulation night).
Time frame: Assessed immediately after each DoA episode during both laboratory overnight recordings (no-stimulation night and stimulation night), up to 6 weeks.
Source-Level EEG Spectral Power (Delta 0.5-4 Hz and Beta 18-30 Hz Bands): Spontaneous vs. Stimulation-Elicited DoA Episodes
Power spectral density in the delta and beta bands, source-localized, compared between spontaneous DoA episodes (no-stimulation night) and stimulation-elicited DoA episodes (stimulation night).
Time frame: Derived from continuous high-density EEG recorded during both laboratory overnight recordings (no-stimulation night and stimulation night), up to 6 weeks.
Odds Ratio of DoA Episode Occurrence During EEG-Defined Fragility vs. Refractory Stimulation Windows (Closed-Loop Feasibility)
Odds ratio of DoA episode occurrence when stimulation is delivered during EEG-defined fragility windows versus randomly selected refractory windows, in the exploratory closed-loop pilot sub-study.
Time frame: Assessed during the closed-loop pilot phase (Phase 3b), within a subset of participants, up to 6 weeks.
Plan to share: Yes — De-identified individual participant data underlying the primary and secondary outcome measures (high-density EEG recordings, episode classification, and questionnaire-derived measures) will be made available following publication of the primary results, in accordance with the SNSF Open Research Data policy and FAIR Data Principles ("as open as possible, as closed as necessary"). Derived and anonymized EEG datasets and analysis code will be deposited in FAIR-compliant, non-commercial repositories (e.g., OpenNeuro, Zenodo) with persistent identifiers, and released under a Creative Commons Attribution license (CC BY 4.0), unless stronger restrictions are required. Raw high-density EEG with synchronized video cannot be made openly available, as full anonymization is not feasible; these data will be deposited only in repositories supporting controlled access (e.g., EBRAINS), with access granted upon reasoned request to a Data Access Committee, subject to a Data Use Agreement and complian
Supporting information: Study protocol, Informed consent form, Analytic code
Time frame: Beginning approximately 12 months after publication of the primary results, with no specified end date.
Access criteria: Access to controlled raw data (EEG with video) is granted upon reasoned request to a Data Access Committee, subject to a Data Use Agreement reviewed by the EOC Data Protection Officer. Anonymized derived datasets and code are openly available without restriction.
No publications or documents are linked to this record.
Start is estimated for Feb 2027; primary completion for Jul 2030, 41 months later.
Start moved once since we started tracking on Sep 25, 2026: Oct 2026 → Feb 2027, on Nov 10, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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Somnambulism