Investigating Near-Threshold Perception During Ultrasonic Deep Brain Stimulation
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 90
- 试验地点
- 1
- 主要终点
- Blood Oxygen Level Dependent (BOLD) response to visual stimuli
研究概览
简要总结
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.
详细描述
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
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •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.
排除标准
- •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.
研究组 & 干预措施
LIFUP-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.
干预措施: Low-intensity focused ultrasound pulsation (LIFUP) (Device)
LIFUP-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.
干预措施: Functional Magnetic Resonance Imaging (fMRI) (Device)
LIFUP-magnetic resonance spectroscopy (MRS)
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.
干预措施: Low-intensity focused ultrasound pulsation (LIFUP) (Device)
LIFUP-magnetic resonance spectroscopy (MRS)
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.
干预措施: Magnetic Resonance Spectroscopy (Device)
LIFUP-Glymphatic MRI
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.
干预措施: Low-intensity focused ultrasound pulsation (LIFUP) (Device)
LIFUP-Glymphatic MRI
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.
干预措施: Multi-modal glymphatic function MRI (Device)
结局指标
主要结局
Blood Oxygen Level Dependent (BOLD) response to visual stimuli
时间窗: 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.
次要结局
- Perceptual criterion (c) derived from the Signal Detection Theory (SDT)(Approximately 65-75 minutes)
- Perceptual sensitivity (d') derived from the Signal Detection Theory (SDT)(Approximately 75 minutes)
研究者
Zirui Huang
Research Associate Professor, Anesthesiology
University of Michigan