Neuromodulation of Conscious Perception: Investigating Thalamic Roles Through Ultrasonic Stimulation

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

Study Overview

• Status: Completed
• Conditions: Thalamus
• Intervention / Treatment: Device: LIFUP excitation; Device: LIFUP inhibition

• Study Type: Interventional
• Enrollment (Actual): 61
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Must be right-handed.
• Must have normal or corrected-to-normal vision (while wearing contact lenses). Please note: persons who need eyeglasses to achieve 20/20 vision 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: persons needing eyeglasses to achieve 20/20 vision 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.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: LIFUP excitation; The 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; 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.
Experimental: LIFUP inhibition; The 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; 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Sensitivity Derived From the Signal Detection Theory (SDT)	SDT was a means of measuring participants' ability to differentiate between information-bearing patterns and random patterns that distract from the information. Sensitivity measured a participant's ability to differentiate between real and scrambled images on a scale from 0.0 to 1.0, with higher scores indicating better accuracy in detecting a signal when it was present and lower scores indicating more missed signals. A score of 1.0 was perfect sensitivity (i.e., never missing a real signal).	Up to 60 minutes after intervention
Change in Perceptual Criterion Derived From the Signal Detection Theory (SDT)	SDT was a means of measuring participants' ability to differentiate between information-bearing patterns and random patterns that distract from the information. Perceptual criterion measured a participant's tendency to say "yes" or "no" when the participant was unsure if a signal was present. Perceptual criterion was measured on a scale from -1.0 to 1.0, with a score of 0 indicating no bias towards "yes" or "no". Negative scores meant a bias towards "yes" (more likely to say a signal was present), while positive scores meant a bias towards "no" (more likely to say a signal was absent).	Up to 60 minutes after intervention

Collaborators and Investigators

• Sponsor: University of Michigan
• Investigators: Principal Investigator: Zirui Huang, University of Michigan; Principal Investigator: Anthony Hudetz, University of Michigan

Study record dates

Study Major Dates

• Study Start (Actual): November 7, 2023
• Primary Completion (Actual): May 13, 2024
• Study Completion (Actual): June 13, 2024

Study Registration Dates

• First Submitted: October 3, 2023
• First Submitted That Met QC Criteria: October 3, 2023
• First Posted (Actual): October 16, 2023

Study Record Updates

• Last Update Posted (Estimated): November 19, 2024
• Last Update Submitted That Met QC Criteria: October 24, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Keywords: Perception
• Other Study ID Numbers: HUM00240514

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes