Neuromodulation of Conscious Perception: Investigating Thalamic Roles Through Ultrasonic Stimulation

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the role that the thalamus (the egg-shaped structure in the middle of your brain) plays in perception using a low-intensity ultrasound pulsation (LIFUP) device. The researchers expect to observe differential changes in the perceptual outcomes based on the LIFUP stimulation of different thalamic areas

Official Title
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Neuromodulation of Conscious Perception: Investigating Thalamic Roles Through Ultrasonic Stimulation

Conditions
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Thalamus

Intervention / Treatment
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* Device: LIFUP excitation
* Device: LIFUP inhibition


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Must be right-handed. Must have normal or corrected-to-normal vision (while wearing contact lenses). Please note: if you need eyeglasses to achieve 20/20 vision, you cannot be included in this study as eyeglasses cannot be worn during the study visit. Must not be on any medications for any neurological, psychological, or psychiatric conditions. Must be English speaking. Must be capable of giving written informed consent. Exclusion Criteria: • Vision that is not 20/20, or vision that is not corrected to 20/20 while wearing contact lenses. Please note: if you need eyeglasses to achieve 20/20 vision, you cannot be included in this study as eyeglasses cannot be worn during the study visit. History of significant head injury with loss of consciousness. Learning disability or other developmental disorder. Medication use for any neurological, psychological, or psychiatric conditions. Any impairment (sensory or motor loss), activity, or situation that in the judgment of the study coordinator or Principal Investigators would prevent satisfactory completion of the study protocol.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: LIFUP excitation<br>Our study will involve the enrollment of 60 participants, who will be randomly assigned to two groups, with each group consisting of 30 participants. The participants will be divided based on the type of transcranial LIFUP they will receive, either excitation or inhibition, targeting four specific thalamic areas. | Device: LIFUP excitation<br>* The experimental will consist of a 10-minute baseline period (LIFUP-OFF) followed by four 10-minute sessions of stimulating (LIFUP-ON-excitation) four thalamic areas. The order of thalamic area stimulation will be counterbalanced across participants and will include the ventral anterior (VA), dorsal anterior (DA), ventral posterior (VP), and dorsal posterior (DP) sections of the thalamus.<br>|
| Experimental: LIFUP inhibition<br>Our study will involve the enrollment of 60 participants, who will be randomly assigned to two groups, with each group consisting of 30 participants. The participants will be divided based on the type of transcranial LIFUP they will receive, either excitation or inhibition, targeting four specific thalamic areas. | Device: LIFUP inhibition<br>* The experimental will consist of a 10-minute baseline period (LIFUP-OFF) followed by four 10-minute sessions of stimulating (LIFUP-ON-inhibition) four thalamic areas. The order of thalamic area stimulation will be counterbalanced across participants and will include the ventral anterior (VA), dorsal anterior (DA), ventral posterior (VP), and dorsal posterior (DP) sections of the thalamus.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity derived from the Signal Detection Theory (SDT) | Sensitivity measures a subject's ability to differentiate between trials with a target present and trials with a target absent | Up to 60 minutes after intervention | 
| Perceptual criterion derived from the Signal Detection Theory (SDT) | Criterion represents a subject's tendency to report subjective recognition of a target stimulus, irrespective of its presence or absence | Up to 60 minutes after intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Perception