Rectal stimulation with EEG to help diagnose disorders of consciousness

Diagnosis Value of Interoceptive EEG Indicators by Rectal Stimulation in Patients With Disorders of Consciousness

This tests whether brief rectal stimulation paired with EEG can reveal brain signals that help diagnose adults who have had a disorder of consciousness for at least 28 days.

Quick facts

• Study type: Observational
• Enrollment: 45 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Hangzhou Normal University (Academic / other)
• Locations: 2 sites (Hefei, Anhui and 1 other locations)
• Trial ID: NCT07208942 on ClinicalTrials.gov

What this trial studies

This observational protocol records EEG responses to controlled rectal stimulation in adult patients with non-acute disorders of consciousness. Investigators will analyze interoception-related EEG indicators and compare them with the Coma Recovery Scale-Revised behavioral classifications to determine concordance. Eligible patients must be medically stable, off sedatives and drugs affecting gut motility, and free of recent infection or major abdominal disease. The work is conducted at The Second People's Hospital of Hefei and Hangzhou Normal University with in-person EEG and stimulation sessions.

Who should consider this trial

Good fit: Ideal candidates are adults (≥18 years) with a non-acute disorder of consciousness (duration ≥28 days) who are medically stable, not recently on sedatives or GI‑motility drugs, and whose families can give consent.

Not a fit: Patients with active infection, recent sedative use, known intestinal disease or prior major abdominal surgery, untreated epilepsy, unstable vital signs, or acute DoC (<28 days) are unlikely to be eligible or benefit.

Why it matters

Potential benefit: If successful, the method could provide an objective EEG biomarker to detect covert consciousness and guide diagnosis and rehabilitation planning.

How similar studies have performed: EEG markers from sensory stimulation paradigms have shown promise for detecting covert consciousness, but using rectal interoceptive stimulation is largely novel and has limited prior evidence.

Eligibility criteria

Inclusion Criteria:

* Patients with non-acute Disorders of Consciousness (DoC) (disease course ≥ 28 days).
* Aged 18 years or older.
* No symptoms of fever, infection, or other similar conditions within 15 days.
* No use of sedatives within 15 days.
* No use of any drugs that may alter gastrointestinal motility within 7 days prior to testing.
* Family members of participating patients have provided consent and signed the informed consent form.

Exclusion Criteria:

* Patients with functional impairments caused by developmental psychiatric disorders or neurological diseases.
* Patients with untreated epilepsy.
* Untreated cerebral edema.
* Patients with unstable vital signs.
* A history of intestinal diseases.
* A history of abdominal surgery other than simple appendectomy or simple cholecystectomy.
* Organic diseases such as spinal cord injury, traumatic brain injury, and thyroid dysfunction.

Where this trial is running

Hefei, Anhui and 1 other locations

• The Second People's Hospital of Hefei — Hefei, Anhui, China (Recruiting)
• Hangzhou Normal University — Hangzhou, Zhejiang, China (Enrolling_by_invitation)

Study contacts

• Study coordinator: YiLin Zhao

Conditions Disorders of Consciousness; Interoceptive; EEG; Rectal Stimulation; Diagnosis