Causal Mechanisms of Odor-Guided Behavior in Humans
National Institute on Drug Abuse (NIDA)
Summary
Background: Little is known about how different regions of the brain responsible for the human sense of smell guide behaviors. In this study, researchers use a technique called transcranial ultrasound stimulation (TUS) to learn how odors affect the brain and behavior. Objective: To learn more about how the human sense of smell works. Eligibility: Healthy people aged 18 to 45 years who are right-handed. Design: Participants can volunteer for up to 2 different experiments. Each experiment requires 5 visits, each about 1 week apart. Food, alcohol, and caffeine may be limited before visits. At the start of each visit, participants will answer questions about their health and how well they slept. Their sense of smell will be assessed. Some visits may include tasks on a computer: While doing these tasks, participants may be asked to smell different odors, look at pictures, and listen to sounds. They will wear devices to track breathing, blood pressure, pulse, and other body responses to the tasks. Some visits may include TUS: TUS uses ultrasound waves to briefly change brain activity. A gel will be applied to the scalp and hair, and a device will be placed against the participant s head. Participants may feel a tapping, pulling, and/or warm sensation on the skin underneath the device. They may also feel a twitch in their face, neck, arm, or leg muscles. Participants will do tasks before and after TUS. Some visits will include functional magnetic resonance imaging (fMRI) scans. fMRI uses magnet and radio waves to capture images of the activity inside the brain. Participants will lie on a table that slides into a tube. They will perform tasks inside the scanner.
Description
Study Description: Primary olfactory cortex has been implicated in a variety of odorguided behaviors in both animal models and humans. However, direct causal evidence for the functional role of different primary olfactory regions in humans is currently missing, due to the lack of non-invasive neuromodulation methods that can effectively target deep brain regions. With the recent advancement of transcranial focused ultrasound stimulation (TUS), this challenge can now be overcome. The goal of this protocol is to use TUS to temporarily modulate activity in primary olfactory cortex and thereby as…
Eligibility
- Age range
- 18–45 years
- Sex
- All
- Healthy volunteers
- No
* INCLUSION CRITERIA In order to be eligible to participate in this study, an individual must meet the following criteria: 1. Willingness to comply with all study procedures and availability for the duration of the study. 2. Aged 18-45 years old. Justification: Many neural processes change with age, and these changes could introduce unwanted variability in the measured signals. 3. In good general health based on the assessment of the Medical Advisory Investigator (MAI). 4. Agreement to adhere to Lifestyle Considerations throughout study duration. Consent signature will be documentation of me…
Interventions
- DeviceTUS PirC
120 seconds of 100 Hz low-intensity transcranial ultrasound stimulation targeting piriform cortex
- DeviceTUS Amy
120 seconds of 100 Hz low-intensity transcranial ultrasound stimulation targeting amygdala
- DeviceTUS Sham
120 seconds of 100 Hz low-intensity transcranial ultrasound stimulation targeting white matter
Location
- National Institute on Drug AbuseBaltimore, Maryland