Consciousness, Level AlteredNCT07840521
Investigating Near-Threshold Perception During Ultrasonic Deep Brain Stimulation
A study testing Low-intensity focused ultrasound pulsation (LIFUP), Functional Magnetic Resonance Imaging (fMRI) and Magnetic Resonance Spectroscopy in people with Consciousness, Level Altered, run by University of Michigan at 1 site in United States.
Trial summary
This research is studying changes in awareness and metabolism in the brain that may take place in various brain regions stimulated with ultrasound (low-intensity focused ultrasound pulsation or LIFUP) while undergoing magnetic resonance imaging (MRI)-based brain measurements. Read more about this study
- Who is it for?
- Ages 18 to 40 yearsHealthy volunteers can take part
- Conditions the study is for
- Consciousness, Level Altered
- What is being tested?
- Low-intensity focused ultrasound pulsation (LIFUP), Functional Magnetic Resonance Imaging (fMRI) and Magnetic Resonance Spectroscopy
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 90 participants
- Where
- 1 siteUnited States
- Study dates
- 30 Nov 2026to Mar 2032
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 40 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Participants must be right-handed, English-speaking, and capable of providing written informed consent.
- Participants must have normal or corrected-to-normal vision while wearing contact lenses,
- Participants must have a body mass index of less than 30
- Participants must not be taking medications for any neurological, psychological, or psychiatric condition.
Who cannot join
- Participants will be excluded if they have any contraindication to MRI scanning, including possible pregnancy, current breastfeeding BMI greater than 30, metallic substances or implants in the body, claustrophobia, anxiety that would prevent MRI scanning, Participants with tattoos in the head or neck region will also be excluded, while tattoos in other locations will be evaluated by the investigators to determine whether they pose a safety concern.
- cardiopulmonary disease, or an intracranial structural abnormality identified on T1-weighted MRI.
- Women of childbearing potential will be required to complete a study-funded pregnancy test before participation and must have a negative result.
- vision that is not 20/20 or corrected to 20/20 with contact lenses, a history of significant head injury involving loss of consciousness
- a learning disability or other developmental disorder
- any sensory or motor impairment, activity, condition, or circumstance that, in the judgment of the study coordinator or Principal Investigators, would prevent satisfactory completion of the study protocol.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
University of Michigan
Ann Arbor, Michigan, 48109
Amy McKinney, 734-647-8129, adrongo@med.umich.edu
Zirui Huang
About this study
This research is studying changes in awareness and metabolism in the brain that may take place in various brain regions stimulated with ultrasound (low-intensity focused ultrasound pulsation or LIFUP) while undergoing magnetic resonance imaging (MRI)-based brain measurements.
Read the detailed description
This study examines the effects of low-intensity focused ultrasound pulsation (LIFUP) on conscious perception and brain physiology in healthy adults using functional Magnetic resonance imaging (MRI), magnetic resonance spectroscopy, or multimodal glymphatic MRI. Participants are assigned by the study team to one of three arms, each involving up to five visits targeting different prespecified brain regions. Participants perform a visual perception task during imaging, with measurements obtained before, during, and after LIFUP. After completing their initially assigned arm, participants may re-enroll in another arm or for a repeat visit following re-screening and new informed consent.
Randomization applies to the order of procedures within each arm, not to assignment of participants among the three arms. The order in which the five brain regions are targeted will be randomized across participants in all three experimental arms
- Conditions
- Consciousness, Level Altered
- Being tested
- Low-intensity focused ultrasound pulsation (LIFUP), Functional Magnetic Resonance Imaging (fMRI), Magnetic Resonance Spectroscopy, Multi-modal glymphatic function MRI
- Medical subject headings
- Consciousness Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Low-intensity focused ultrasound pulsation (LIFUP)Device
LIFUP will be used to stimulate specific brain regions and assess their causal involvement in the control of conscious state and contents.
Functional Magnetic Resonance Imaging (fMRI)Device
Whole-brain functional images will be acquired using a multiband gradient-echo echo-planar imaging sequence with the following parameters: 60 slices, repetition time (TR) = 800 ms, echo time (TE) = 30 ms, flip angle = 52°, multiband acceleration factor = 6, slice thickness = 2.4 mm, in-plane resolution = 2.4 × 2.4 mm, FOV = 216 × 216 mm, and image matrix = 90 × 90. MRI acquisition and associated study procedures will be completed within a scanning visit lasting no more than approximately 2 hours.
Magnetic Resonance SpectroscopyDevice
Single-voxel proton magnetic resonance spectroscopy will be performed. A nominal 15 × 15 × 10 mm spectroscopy voxel will be positioned at the prespecified brain target using the participant's anatomical MRI. Glutamate plus glutamine (Glx) will be measured using a short-echo-time spectroscopy sequence with an acquisition time of approximately 5 minutes. GABA will be measured using an edited spectroscopy sequence with an acquisition time of approximately 8 minutes. An unsuppressed water-reference scan will also be acquired for signal correction and metabolite quantification. Voxel placement, shimming, and other sequence parameters may be adjusted slightly based on target anatomy, scanner requirements, and data quality while maintaining the planned procedures and approximate acquisition times.
Multi-modal glymphatic function MRIDevice
The study team will collect three separate measurements related to glymphatic function. (i) Multi-delay pseudo-continuous arterial spin labeling (PCASL) MRI with a 3D stack of spirals (SOS) gradient and spin echo (GRASE) read-out. Labeling durations from 500 to 2000 ms, TR = 6 sec., background suppression. FOV = 24 cm with 3x3x5 mm resolution. (ii) Tissue-to-fluid Water exchange rate using T2 selective saturation labeling pulses using the same resolution parameters. (iii) Velocity Spectrum Imaging using velocity selective preparation pulses followed by spherical spiral projection imaging (FOV = 24 cm, velocity bandwidth = [-1, 1] cm/s, isotropic spatial resolution = 3.5 mm).
| Study group | Role | What they receive |
|---|---|---|
| LIFUP-fMRI | Experimental | Participants assigned to the fMRI arm will complete five visits, with a different brain region targeted at each visit. Each visit will include seven consecutive 10-minute scanning periods: one pre-LIFUP baseline fMRI scan, five fMRI scans conducted during LIFUP using five predefined combinations of duty cycle and pulse repetition frequency, and one post-LIFUP baseline fMRI scan. The five stimulation parameter combinations will be labeled Combination 1 through Combination 5. The order of the five parameter combinations will be randomized within each visit. The total planned scanning time for these seven periods is approximately 70 minutes, excluding structural imaging, participant positioning, transducer placement, safety checks, and other required study procedures. Receives: Device: Low-intensity focused ultrasound pulsation (LIFUP); Device: Functional Magnetic Resonance Imaging (fMRI) |
| LIFUP-magnetic resonance spectroscopy (MRS) | Experimental | Participants assigned to the MRS arm will also complete five visits, with a different brain region targeted at each visit. Each visit will include a pre-LIFUP baseline MRS acquisition, an excitatory LIFUP condition, a post-excitatory non-LIFUP MRS acquisition, an inhibitory LIFUP condition, and a post-inhibitory non-LIFUP MRS acquisition. Each MRS acquisition period will last approximately 13 minutes and will include approximately 5 minutes of glutamate plus glutamine measurement and 8 minutes of gamma-aminobutyric acid (GABA) measurement. The order of the excitatory and inhibitory LIFUP conditions will be randomized across participants. Receives: Device: Low-intensity focused ultrasound pulsation (LIFUP); Device: Magnetic Resonance Spectroscopy |
| LIFUP-Glymphatic MRI | Experimental | Participants assigned to the glymphatic MRI arm will complete up to five visits, with a different prespecified brain region targeted at each visit. Tissue-to-fluid water exchange, velocity spectrum imaging, and cerebral perfusion using arterial spin labeling will be assessed before, during, and after LIFUP. The planned imaging periods total approximately 1.5 hours per visit, excluding participant positioning, structural imaging, transducer placement, safety checks, and other required study procedures. Receives: Device: Low-intensity focused ultrasound pulsation (LIFUP); Device: Multi-modal glymphatic function MRI |
What is being measured
The primary outcome is the main question the study is designed to answer.
Blood Oxygen Level Dependent (BOLD) response to visual stimuli
Changes in task-evoked blood oxygen level-dependent responses to visual stimuli will be measured using functional MRI before, during, and after LIFUP across the five stimulation parameter conditions.
Measured: Approximately 70 minutes
Secondary outcomes (2)
Perceptual criterion (c) derived from the Signal Detection Theory (SDT)
The perceptual response criterion, c, will be calculated from participants' recognition responses using Signal Detection Theory to quantify their tendency to report conscious recognition of a visual stimulus.
For each scanning session, the study team will calculate sensitivity (d') and criterion (c) using subjective reports of recognition as "yes" or "no".
Measured: Approximately 65-75 minutes
Perceptual sensitivity (d') derived from the Signal Detection Theory (SDT)
Perceptual sensitivity, d', will be calculated from participants' visual discrimination responses using Signal Detection Theory to quantify their ability to distinguish intact object images from control stimuli.
For each scanning session, the study team will calculate sensitivity (d') and criterion (c) using subjective reports of recognition as "yes" or "no".
Measured: Approximately 75 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Sep 2026
- Study start30 Nov 2026 (estimated)
- Primary completionMar 2032 (estimated)
- Study completionMar 2032 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Consciousness, Level AlteredStudies of the same condition, open and under way.
- More trials run by University of MichiganThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 90 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Michigan
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute of General Medical Sciences (NIGMS)
- Responsible party
- Principal investigator, Zirui Huang, University of Michigan
- Investigators
- Zirui Huang, Principal investigator, University of Michigan
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07840521
- Sponsor's protocol ID
- HUM00251769
- Other IDs
- 2R01GM103894
- Status last verified
- Oct 2026
- First submitted
- 18 Sep 2026
- Last updated
- 13 Oct 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 13 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Investigating Near-Threshold Perception During Ultrasonic Deep Brain Stimulation
- ClinicalTrials.gov ID
- NCT07840521
- Acronym / sponsor ID
- HUM00251769
- Conditions
- Consciousness, Level Altered
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 90 participants (estimated)
- Lead sponsor
- University of MichiganUniversity, hospital or other
- Collaborators
- National Institute of General Medical Sciences (NIGMS)
- Study start
- 30 Nov 2026 (estimated)
- Primary completion
- Mar 2032 (estimated)
- Study completion
- Mar 2032 (estimated)
- First posted
- 25 Sep 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This research is studying changes in awareness and metabolism in the brain that may take place in various brain regions stimulated with ultrasound (low-intensity focused ultrasound pulsation or LIFUP) while undergoing magnetic resonance imaging (MRI)-based brain measurements.
Detailed description
This study examines the effects of low-intensity focused ultrasound pulsation (LIFUP) on conscious perception and brain physiology in healthy adults using functional Magnetic resonance imaging (MRI), magnetic resonance spectroscopy, or multimodal glymphatic MRI. Participants are assigned by the study team to one of three arms, each involving up to five visits targeting different prespecified brain regions. Participants perform a visual perception task during imaging, with measurements obtained before, during, and after LIFUP. After completing their initially assigned arm, participants may re-enroll in another arm or for a repeat visit following re-screening and new informed consent.
Randomization applies to the order of procedures within each arm, not to assignment of participants among the three arms. The order in which the five brain regions are targeted will be randomized across participants in all three experimental arms
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| LIFUP-fMRI | Experimental | Device: Low-intensity focused ultrasound pulsation (LIFUP), Device: Functional Magnetic Resonance Imaging (fMRI)Participants assigned to the fMRI arm will complete five visits, with a different brain region targeted at each visit. Each visit will include seven consecutive 10-minute scanning periods: one pre-LIFUP baseline fMRI scan, five fMRI scans conducted during LIFUP using five predefined combinations of duty cycle and pulse repetition frequency, and one post-LIFUP baseline fMRI scan. The five stimulation parameter combinations will be labeled Combination 1 through Combination 5. The order of the five parameter combinations will be randomized within each visit. The total planned scanning time for these seven periods is approximately 70 minutes, excluding structural imaging, participant positioning, transducer placement, safety checks, and other required study procedures. |
| LIFUP-magnetic resonance spectroscopy (MRS) | Experimental | Device: Low-intensity focused ultrasound pulsation (LIFUP), Device: Magnetic Resonance SpectroscopyParticipants assigned to the MRS arm will also complete five visits, with a different brain region targeted at each visit. Each visit will include a pre-LIFUP baseline MRS acquisition, an excitatory LIFUP condition, a post-excitatory non-LIFUP MRS acquisition, an inhibitory LIFUP condition, and a post-inhibitory non-LIFUP MRS acquisition. Each MRS acquisition period will last approximately 13 minutes and will include approximately 5 minutes of glutamate plus glutamine measurement and 8 minutes of gamma-aminobutyric acid (GABA) measurement. The order of the excitatory and inhibitory LIFUP conditions will be randomized across participants. |
| LIFUP-Glymphatic MRI | Experimental | Device: Low-intensity focused ultrasound pulsation (LIFUP), Device: Multi-modal glymphatic function MRIParticipants assigned to the glymphatic MRI arm will complete up to five visits, with a different prespecified brain region targeted at each visit. Tissue-to-fluid water exchange, velocity spectrum imaging, and cerebral perfusion using arterial spin labeling will be assessed before, during, and after LIFUP. The planned imaging periods total approximately 1.5 hours per visit, excluding participant positioning, structural imaging, transducer placement, safety checks, and other required study procedures. |
Who may qualify
- Ages
- 18 to 40 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Participants must be right-handed, English-speaking, and capable of providing written informed consent.
- Participants must have normal or corrected-to-normal vision while wearing contact lenses,
- Participants must have a body mass index of less than 30
- Participants must not be taking medications for any neurological, psychological, or psychiatric condition.
Key exclusion criteria (6 listed)
- Participants will be excluded if they have any contraindication to MRI scanning, including possible pregnancy, current breastfeeding BMI greater than 30, metallic substances or implants in the body, claustrophobia, anxiety that would prevent MRI scanning, Participants with tattoos in the head or neck region will also be excluded, while tattoos in other locations will be evaluated by the investigators to determine whether they pose a safety concern.
- cardiopulmonary disease, or an intracranial structural abnormality identified on T1-weighted MRI.
- Women of childbearing potential will be required to complete a study-funded pregnancy test before participation and must have a negative result.
- vision that is not 20/20 or corrected to 20/20 with contact lenses, a history of significant head injury involving loss of consciousness
- a learning disability or other developmental disorder
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Low-intensity focused ultrasound pulsation (LIFUP)LIFUP will be used to stimulate specific brain regions and assess their causal involvement in the control of conscious state and contents. | Device | LIFUP-Glymphatic MRI, LIFUP-fMRI, LIFUP-magnetic resonance spectroscopy (MRS) |
| Functional Magnetic Resonance Imaging (fMRI)Whole-brain functional images will be acquired using a multiband gradient-echo echo-planar imaging sequence with the following parameters: 60 slices, repetition time (TR) = 800 ms, echo time (TE) = 30 ms, flip angle = 52°, multiband acceleration factor = 6, slice thickness = 2.4 mm, in-plane resolution = 2.4 × 2.4 mm, FOV = 216 × 216 mm, and image matrix = 90 × 90. MRI acquisition and associated study procedures will be completed within a scanning visit lasting no more than approximately 2 hours. | Device | LIFUP-fMRI |
| Magnetic Resonance SpectroscopySingle-voxel proton magnetic resonance spectroscopy will be performed. A nominal 15 × 15 × 10 mm spectroscopy voxel will be positioned at the prespecified brain target using the participant's anatomical MRI. Glutamate plus glutamine (Glx) will be measured using a short-echo-time spectroscopy sequence with an acquisition time of approximately 5 minutes. GABA will be measured using an edited spectroscopy sequence with an acquisition time of approximately 8 minutes. An unsuppressed water-reference scan will also be acquired for signal correction and metabolite quantification. Voxel placement, shimming, and other sequence parameters may be adjusted slightly based on target anatomy, scanner requirements, and data quality while maintaining the planned procedures and approximate acquisition times. | Device | LIFUP-magnetic resonance spectroscopy (MRS) |
| Multi-modal glymphatic function MRIThe study team will collect three separate measurements related to glymphatic function. (i) Multi-delay pseudo-continuous arterial spin labeling (PCASL) MRI with a 3D stack of spirals (SOS) gradient and spin echo (GRASE) read-out. Labeling durations from 500 to 2000 ms, TR = 6 sec., background suppression. FOV = 24 cm with 3x3x5 mm resolution. (ii) Tissue-to-fluid Water exchange rate using T2 selective saturation labeling pulses using the same resolution parameters. (iii) Velocity Spectrum Imaging using velocity selective preparation pulses followed by spherical spiral projection imaging (FOV = 24 cm, velocity bandwidth = [-1, 1] cm/s, isotropic spatial resolution = 3.5 mm). | Device | LIFUP-Glymphatic MRI |
Primary outcome
Blood Oxygen Level Dependent (BOLD) response to visual stimuli
Time frame: Approximately 70 minutes
Changes in task-evoked blood oxygen level-dependent responses to visual stimuli will be measured using functional MRI before, during, and after LIFUP across the five stimulation parameter conditions.
2 secondary outcomes
Perceptual criterion (c) derived from the Signal Detection Theory (SDT)
Time frame: Approximately 65-75 minutes
Perceptual sensitivity (d') derived from the Signal Detection Theory (SDT)
Time frame: Approximately 75 minutes
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 13 Oct 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Zirui Huang principal investigator
University of Michigan
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Low-intensity focused ultrasound pulsation (LIFUP), Functional Magnetic Resonance Imaging (fMRI) and Magnetic Resonance Spectroscopy in people with Consciousness, Level Altered, run by University of Michigan at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 13 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Amy McKinney (734-647-8129, adrongo@med.umich.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Blood Oxygen Level Dependent (BOLD) response to visual stimuli (time frame: Approximately 70 minutes). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 Oct 2026.