Tactile Stimulation in Disorders of Consciousness (DoC)

NCT ID: NCT06922123

Last Updated: 2025-04-23

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Total Enrollment: 30 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-04-30
• Study Completion Date: 2025-10-31

Brief Summary

The aim of this project is to evaluate the behavioural and neurophysiological responses to pleasant touch in patients with disorders of consciousness (DoC) and to determine whether these responses are related to the level of consciousness. Specifically, the study aims to:

1. explore the relationship between pleasant tactile stimulation and behavioural and neurophysiological responses in patients with DoC;

2. determine whether behavioural responses to pleasant touch stimulation correlate with the level of consciousness;

3. assess whether behavioural responses vary depending on the valence of the stimulus (pleasant, neutral, or unpleasant);

4. examine neurophysiological responses to tactile stimulation using functional near-infrared spectroscopy (fNIRS), and evaluate whether brain activation patterns are associated with behavioural responses;

5. improve diagnostic accuracy in patients with DoC by exploring the value of somatosensory responses in distinguishing unresponsive wakefulness syndrome (UWS) from minimally conscious state (MCS) or conscious patients;

6. explore the potential usefulness of implementing this type of stimulation within rehabilitation programs to support better recovery of consciousness.

Detailed Description

Patients will be enrolled at the participating centers and included in the study only after at least two evaluations using the Coma Recovery Scale-Revised (CRS-R), in order to ensure a stable diagnosis of the level of consciousness.

At the beginning of the protocol, non-invasive fNIRS optodes will be placed on the patient's forehead using a frontal headband, and 15 minutes of resting-state brain activity will be recorded. The Simplified Evaluation of CONsciousness Disorders (SECONDs) will then be administered to assess the patient's level of consciousness, followed by the tactile stimulation protocol.

The tactile stimulation protocol involves 8 areas of the body (anterior and posterior forearm, palm and back of the hand, on both right and left sides) and 6 stimuli grouped into three categories: pleasant objects (makeup brush, plush fabric), neutral objects (sponge, rubber fabric), and unpleasant objects (dishnet, hairbrush). Each stimulus is mounted on a 10 cm wooden stick attached to a cork base. Each stimulation lasts 15 seconds and is manually administered using light circular movements over an area of approximately 5 cm² at a speed of 5 cm/s, following a randomized sequence. A 10-second rest period will be provided between stimulations. Patients will receive three distinct blocks of stimulation: unpleasant stimuli (first block), pleasant stimuli (second block), and neutral stimuli (third block), with the block order randomized across participants. After each block, the SECONDs will be re-administered to detect any changes in the level of consciousness. An additional 15-minute resting-state fNIRS recording will follow the stimulation phase.

All sessions will be video-recorded to allow two independent experimenters to evaluate behavioural responses (e.g., facial expressions, vocalizations, body movements, and emotional reactions such as crying, smiling, or grimacing) and compare the effects of different stimulations. At the end of the session, fNIRS optodes will be removed.

The entire experimental procedure will last approximately 90 minutes.

Conditions

Disorders of Consciousness

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Patients with Disorders of Consciousness (DoC)

All patients with disorders of consciousness who are consecutively admitted to the participating centers of the study will be enrolled with a diagnosis of disorders of consciousness based on the CRS-R scale, with an age ≥18 years and a time since the event ≥ 28 days.

Tactile stimulation

Intervention Type: BEHAVIORAL

Patients will undergo a resting-state EEG and fNIRS recording, followed by the administration of the SECONDs scale. Tactile stimulation will then be performed on eight areas of the body (internal and external forearms, palms and backs of the hands on both sides) using six different stimuli categorized as pleasant, neutral, or unpleasant. Stimuli will be applied manually in randomized blocks. EEG and fNIRS data will be recorded before, during, and after stimulation. Behavioural responses will be evaluated through video analysis by independent raters. The session will last approximately 90 minutes.

Neurophysiological Monitoring with SedLine

Intervention Type: DEVICE

SedLine is a non-invasive neurophysiological monitoring device used to record the brain's electrical activity (EEG) through frontal electrodes. In this study, SedLine is employed to measure resting-state and stimulus-evoked cortical responses in patients with disorders of consciousness (DoC), in combination with functional near-infrared spectroscopy (fNIRS). The EEG signals are used to assess changes in neural activity before, during, and after tactile stimulation with various affective valences (pleasant, neutral, unpleasant). This combined multimodal approach enhances the understanding of sensory processing and cortical reactivity in patients with impaired consciousness.

Interventions

Tactile stimulation

Patients will undergo a resting-state EEG and fNIRS recording, followed by the administration of the SECONDs scale. Tactile stimulation will then be performed on eight areas of the body (internal and external forearms, palms and backs of the hands on both sides) using six different stimuli categorized as pleasant, neutral, or unpleasant. Stimuli will be applied manually in randomized blocks. EEG and fNIRS data will be recorded before, during, and after stimulation. Behavioural responses will be evaluated through video analysis by independent raters. The session will last approximately 90 minutes.

Intervention Type: BEHAVIORAL

Neurophysiological Monitoring with SedLine

SedLine is a non-invasive neurophysiological monitoring device used to record the brain's electrical activity (EEG) through frontal electrodes. In this study, SedLine is employed to measure resting-state and stimulus-evoked cortical responses in patients with disorders of consciousness (DoC), in combination with functional near-infrared spectroscopy (fNIRS). The EEG signals are used to assess changes in neural activity before, during, and after tactile stimulation with various affective valences (pleasant, neutral, unpleasant). This combined multimodal approach enhances the understanding of sensory processing and cortical reactivity in patients with impaired consciousness.

Intervention Type: DEVICE

Other Intervention Names

SedLine EEG Monitor; Masimo SedLine

Eligibility Criteria

Inclusion Criteria

• Clinical diagnosis of a disorder of consciousness (DoC), as determined by repeated Coma Recovery Scale-Revised (CRS-R) assessments;
• Age ≥ 18 years;
• Time since acute event ≥ 28 days.
• Written informed consent obtained from the legal representative

Exclusion Criteria

• Presence of large craniectomy that may interfere with fNIRS signal acquisition;
• Unstable clinical conditions (e.g., respiratory insufficiency, fever, status epilepticus);
• Fractures, paralysis, lesions, or muscular atrophy that prevent proper tactile stimulation of the specified body areas;
• Absence of informed consent from the legal representative.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Liege

OTHER

Sponsor Role: collaborator

Anna Estraneo

OTHER

Sponsor Role: lead

Responsible Party

Anna Estraneo

MD Neurologist Senior researcher

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Anna Estraneo, MD

Role: PRINCIPAL_INVESTIGATOR

Fondazione Don Gnocchi

Olivia Gosseries, PhD, Professor

Role: PRINCIPAL_INVESTIGATOR

University of Liege

Central Contacts

Simona Simona Abagnale, PhD

Role: CONTACT

sabagnale@dongnocchi.it

+39 3487520258

Anna Estraneo, MD Study Principal Investigat

Role: CONTACT

aestraneo@dongnocchi.it

Other Identifiers

TACTILE-DOC

Identifier Type: -

Identifier Source: org_study_id