Transcranial Ultrasonic Neuromodulation of Primary Visual Cortex and Primary Auditory Cortex in Humans

NCT07508722 | Not Yet Recruiting

• 2 other identifiers: 2507001708TI25-5201
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

There are a number of disorders of the brain that have limited treatment options, such as chronic pain, addiction, and major depression. A new technology has emerged in the last decade known as transcranial focused ultrasound, which can deliver focused acoustic signals through the skull to modulate brain activity over a small region, including structures deep in the brain. This has resulted in many ongoing clinical trials for various disorders, but there is still a lack of understanding of the optimal sonication parameters for increasing versus decreasing brain activity. The investigators aim to address this open question by sonicating the primary visual cortex and primary auditory cortex in human with a range of sonication parameters. These brain structures were chosen to target because they are expected to elicit perceptual responses in the subject (i.e., the subject will report visual and auditory perception during sonication), allowing the experimenters to infer directly the extent to which neural signals can propagate through the visual and auditory systems in a way that is sufficient to produce conscious perception. Such findings have applications not only in clinical treatments, but also in the fundamental science of the neural basis of sensory perception. Previous work has shown that sonicating the visual cortex in humans can elicit visual perception, but the ultrasonic system in prior work did not have the focusing capabilities that will be employed in this study. At the end of this study, the investigators will have determined the optimal sonication parameters that can elicit neural responses over a small volume over sensory cortex, which can be inferred from visual percepts being localized in space (e.g., a bright spot as opposed to a diffuse light), and auditory percepts that sound like pure tones rather than a broad set of frequencies (e.g., sounding like white noise or static).

Conditions

Healthy Volunteers; no Condition, Basic Science

Keywords

Transcranial Focused Ultrasound; Non-invasive Brain Stimulation; Ultrasound Neuromodulation

Outcome Measures

Primary Outcomes (3)

• Change in sensory-evoked cortical response measured by electroencephalography

  Change in peak-to-peak amplitude (µV) of sensory-evoked potentials recorded from scalp electroencephalography (EEG) over the targeted cortical region (visual or auditory cortex, depending on stimulation condition) during and after transcranial focused ultrasound stimulation, relative to baseline (pre-stimulation).

  Measured during Visit 2 (baseline, during stimulation, immediately post-stimulation, and 15-20 minutes post-stimulation)

• Change in visual detection threshold

  Change in visual sensitivity thresholds measured using the visual field analyzer, quantified as detection threshold before and after transcranial focused ultrasound stimulation.

  Baseline (Visit 1); pre-stimulation (Visit 2); immediately after stimulation (Visit 2); and 1 week after stimulation (Visit 3)

• Change in auditory tone detection threshold

  Change in auditory detection thresholds measured using commercial audiometry system (e.g., WAHTS Hearing), quantified as minimum detectable sound level (dB HL) across frequencies (250 Hz-8 kHz) before and after transcranial focused ultrasound stimulation.

  Baseline (Visit 1); pre-stimulation (Visit 2); immediately after stimulation (Visit 2); and 1 week after stimulation (Visit 3)

Secondary Outcomes (2)

• Participant-reported perceptual intensity measured by numeric rating scale during transcranial focused ultrasound stimulation

  During each stimulation block (each approximately 6-7 minutes; up to 20 minutes total) at Visit 2

• Number of participants with new structural brain abnormalities on MRI following transcranial focused ultrasound stimulation

  1 week after stimulation (Visit 3)

Study Arms (1)

Experimental: Transcranial Focused Ultrasound Stimulation

EXPERIMENTAL

Participants complete three visits. Visit 1 includes informed consent, baseline visual or auditory testing, and magnetic resonance imaging (MRI) for target localization. Visit 2 includes electroencephalography (EEG) recording and low-intensity transcranial focused ultrasound (tFUS) delivered to either primary visual cortex or primary auditory cortex (each participant receives one target only). Three ultrasound pulse durations are delivered in randomized order while EEG and behavioral responses are measured before, during, and after stimulation. Visit 3 (≥1 week later) includes repeat behavioral testing and a follow-up structural MRI.

Device: Transcranial Focused Ultrasound Stimulation; Device: Electroencephalography; Device: Magnetic Resonance Imaging

Interventions

Transcranial Focused Ultrasound Stimulation DEVICE

Low-intensity transcranial focused ultrasound delivered to either the primary visual cortex or primary auditory cortex using a research ultrasound system. Three pulse durations are tested in randomized order during a single study session while brain activity and behavioral responses are measured.

Also known as: Low-Intensity Focused Ultrasound (LIFU)

Experimental: Transcranial Focused Ultrasound Stimulation

Electroencephalography DEVICE

Noninvasive recording of brain electrical activity from scalp electrodes before, during, and after ultrasound stimulation.

Also known as: EEG

Experimental: Transcranial Focused Ultrasound Stimulation

Magnetic Resonance Imaging DEVICE

Structural and functional magnetic resonance imaging used for anatomical localization of stimulation targets and follow-up safety assessment.

Also known as: MRI

Experimental: Transcranial Focused Ultrasound Stimulation

Eligibility Criteria

• Age: 21 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy male and female adults aged 21-55.
• No contraindications to magnetic resonance imaging (MRI) scans, such as claustrophobia.

You may not qualify if:

• History of major medical, neurological (including peripheral nerve disease) or psychiatric illness.
• History of vsacular conditions, predisposition to hemorrhage, or blood thinner medications
• History of head trauma with loss of consciousness.
• Use of sedatives, analgesics and agents that affect brain function.
• Contraindications for exposure to the high magnetic field of MRI imaging
• History of skin irritation from acoustic coupling materials such as a water-based gel and polyvinyl alcohol (PVA; a common household plastic bag material).
• Vulnerable subpopulations (pregnant women, children, institutionalized individuals).
• Use of excessive alcohol (e.g., no more than one can of beer or glass of wine) or strenuous exercise (e.g., no more than daily routine) on the day of the visit

Sponsors & Collaborators

• Massachusetts Institute of Technology: lead
• MIT Lincoln Laboratory: collaborator

Study Sites (1)

Massachusetts Institute of Technology - McGovern Institute for Brain Research

Cambridge, Massachusetts, 02139, United States

Location

Related Publications (1)

• Freeman DK, Odegaard B, Yoo SS, Michel M. Transcranial focused ultrasound for identifying the neural substrate of conscious perception. Neurosci Biobehav Rev. 2026 Jan;180:106485. doi: 10.1016/j.neubiorev.2025.106485. Epub 2025 Nov 19.

  PMID: 41270981 BACKGROUND

MeSH Terms

Interventions

Electroencephalography; Magnetic Resonance Imaging

Intervention Hierarchy (Ancestors)

Diagnostic Techniques, Neurological; Diagnostic Techniques and Procedures; Diagnosis; Electrodiagnosis; Tomography; Diagnostic Imaging

Central Study Contacts

Daniel K Freeman, Ph.D.

CONTACT

617-877-7145; Daniel.Freeman@ll.mit.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 27, 2026
• First Posted: April 2, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): November 18, 2026
• Study Completion (Estimated): June 1, 2027
• Last Updated: April 2, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)