Measuring Single Neuron Activity in the Brain

Not Applicable

Not yet recruiting

• Conditions: Neurological Diseases or Conditions

• Registration Number: NCT06763471
• Lead Sponsor: University College, London

Brief Summary

The SUNAN (Single Unit Neurophysiological Architecture of the Neocortex) study aims to understand how individual brain cells called neurons interact and communicate, and how the neurons can be affected in neurological disease. Using an advanced digital probe called the "Neuropixels probe," which is as thin as a human hair, the investigators can record electrical activity from individual neurons on the outmost layer of the brain (cerebral cortex). This electrical (neurophysiological) activity recording technique allows the investigators to isolate and monitor single-neuron activity from the human brain during planned neurosurgical operations in real time.

Detailed Description

The SUNAN study plans to recruit fifty patients scheduled for brain surgery, such as for tumour removal or operations that involve the fluid (cerebrospinal fluid) within the brain, at the National Hospital for Neurology and Neurosurgery. Participation is voluntary, and the suitability will be assessed by the participant's neurosurgeon.

Patients who participate in SUNAN will undergo their planned neurosurgery as per standard of care with the additional step of a neurophysiological recording made from the brain using a Neuropixels probe. This recording step and the data collected will not affect the rest of the patients care which will proceed in the usual way and the data is collected solely for scientific purposes.

The investigators believe that the insights gained from these electrical recordings from individual neurons will deepen our understanding of brain function and potentially lead to improved diagnosis and treatment of neurological diseases.

Study Timeline

• Status Verified: 2024-12
• Study First Submitted: 2024-12-20
• Study First Submitted QC: 2025-01-06
• Last Update Submitted: 2025-01-06
• Study First Posted: 2025-01-08
• Last Update Posted: 2025-01-08
• Study Start: 2025-02
• Primary Completion: 2027-02
• Study Completion: 2028-02

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

Not provided

Exclusion Criteria

1. Participants who lack the capacity to give informed consent.
2. Participants who are pregnant or breast feeding at the time of surgery.
3. Participants deemed to be unsuitable for recruitment to the study by the responsible Consultant Neurosurgeon. If in the view of the treating consultant involvement in the study would compromise the patient's surgery or present an unacceptable risk to them, they will not be recruited to the study. For example, if the participant does not meet the standard of care preoperative checks.
4. Concern from the Consultant Neurosurgeon or treating Anaesthetist that there would be an unreasonable burden on the patient to participate in the study. For example, risk due to increased length of anaesthetic time.
5. For participants requiring anaesthesia for their pre-planned brain surgery, an American Society of Anaesthesiologists (ASA) physical status classification system score of 4 and higher.
6. Participants unable to understand English sufficiently well to read the patient facing documents and consent in English.
7. Participants not undergoing their treatment through National Health Service (NHS) care (i.e. private patients are excluded).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
Single units isolated	Timepoint - At time of planned neurosurgery.	Outcome name - Descriptive reporting on the number of well isolated single neuronal units observed during neurophysiological recording of the brain during planned neurosurgery.; Metric/method of measurement - Neurophysiological activity of the brain will be described through analysis of electrical activity recorded. The detection of spikes represents depolarisation of single neuronal units ("single-units"). Well isolated single-units will be defined by clustering metrics, interval spike interval violations and/or other neurophysiological analysis. Descriptive reporting will include the number of individual units recorded, their spiking rates and correlation.

Secondary Outcome Measures

Name	Time	Method
Experience of using large scale single-unit recording	Through study completion, an average of 1 year	Secondary outcome measures will be reported for each participant to gather information on the recording technique. For example, a description of the recording setting may include the arrangement of ground and reference electrodes as well as the operative set-up.; Reporting on the experience of using large scale single-unit recording techniques in humans undergoing neurosurgery.
Iterations made to the surgical and electrophysiological technique	Through study completion, an average of 1 year	Reporting on iterations made to the surgical and electrophysiological technique over the course of the study.
Potential refinements in technique	Through study completion, an average of 1 year	Reporting on potential refinements that could be made to the described technique which could enable better quality data and that could be of benefit to other researchers conducting similar work. For example, equipment set-up/noise restrictions in theatre.