Causal Mechanisms of Odor-Guided Behavior in Humans

De qué trata este estudio

El registro no identifica actualmente este estudio como reclutando. Consulta su estado antes de planificar una evaluación.

Tipo de estudio

De intervención

Fase

Fase 1 temprana

Rango de edad

18 años - 45 años

Sexo admitido

Todos los sexos

Voluntarios sanos

No aceptados

Participantes

80 Estimado

Estos son puntos de partida, no una decisión de elegibilidad. El equipo debe revisar todos los requisitos.

Acerca de la investigación

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.

¿Quién podría participar?

La lista siguiente contiene el texto del patrocinador. Puede incluir condiciones, tratamientos previos, resultados de pruebas y otros requisitos. Aparecer en tu búsqueda no significa que califiques.

• INCLUSION CRITERIA:

In order to be eligible to participate in this study, an individual must meet the following criteria:

1. Aged 18-45 years old. Justification: Many neural processes change with age, and these changes could introduce unwanted variability in the measured signals.
2. In good general health based on the assessment of the Medical Advisory Investigator (MAI) or delegate.
3. Right-handed.

EXCLUSION CRITERIA:

Individuals who meet any of the following criteria will be excluded from participation:

1. Any neurological disorder that would increase seizure risk from TUS such as stroke, brain lesions, previous neurosurgery, epilepsy, any history of seizure or fainting episode of unknown cause, frequent severe headache, or head trauma resulting in loss of consciousness, lasting over 30 minutes or with sequela lasting longer than one month. The MAI will also retain discretion to exclude based on a history of a neurological illness or trauma that may compromise safety or data integrity.
2. Predisposition to seizures (e.g., first-degree family history of potentially hereditary epilepsy, etc.).
3. Current use (any use in the past week, daily use for more than one week within past 3 months) of any investigational drug or of any medications with psychotropic (e.g., benzodiazepines, etc.), or anti or pro-convulsive action. This will be determined at the discretion of the MAI.
4. Unable to undergo MRI, or TUS due to certain metallic or magnetic devices or implants in the body, claustrophobia, or other reasons including numbness or paresthesia of the head.
5. History of noise-induced hearing loss or tinnitus.
6. Recent history (within past 12 months) of learning disability, major DSM-5 psychiatric disorder including major affective disorder, ADHD, obsessivecompulsive disorder, schizophrenia, or PTSD. This will be determined at the discretion of the MAI.
7. Pattern of alcohol and drug use in the past 12 months that is indicative of harmful use, loss of control over use, or physical dependence.
8. Daily nicotine, alcohol, or drug use (excluding caffeine) for at least 4 continuous weeks within the past 12 months.
9. Participation in any neuromodulation (e.g., TMS, TUS, tDCS, tACS, etc.) session (excluding the current protocol) in the past two weeks.
10. History of anaphylaxis and/or severe food and non-food allergies (e.g., latex, detergents, soap, etc.).
11. History of significant chronic obstructive pulmonary disease (COPD) or severe, uncontrolled asthma, as increased levels of carbon dioxide may increase the susceptibility to cavitation and related tissue damage.
12. Uncorrected impairments in visual acuity severe enough to affect task participation.
13. Non-English speaking. Justification: Data integrity of some of the behavioral tasks used in this study would be compromised as they have only been validated in English. Most importantly, ongoing communication regarding safety procedures is necessary when participants are undergoing TUS and MRI procedures. The inability to effectively communicate TUS and MRI safety procedures in a language other than English could compromise the safety of non-English speaking participants.
14. Serious skin disease involving the hands or head, or history of serious systemic allergy involving the skin or mucous membranes such as Stevens-Johnson syndrome, or known history of contact dermatitis to ultrasound gel. Justification: Gel will be applied to the skin on both head and hands, for transducer coupling and electrode placement, respectively. Allergic or adverse reactions to such treatment need to be ruled out.
15. Hyposmia, i.e., decreased sense of smell, or anosmia, i.e., loss of smell (Sniffin' Sticks Olfactory Identification Score \< 10). Justification: The ability to smell is paramount to task performance.
16. Pregnancy. Justification: It is unknown whether MRI and/or TUS pose risks to fetuses.
17. Any other condition that in the judgment of the investigators is incompatible with participation.

Tratamiento, grupos y participación

El registro puede describir tratamientos y duración sin incluir un calendario completo. Pide al equipo las visitas, procedimientos, riesgos, costos y alternativas. Mantén tu atención habitual salvo que tu médico te indique un cambio.

Asignación

Sin asignación al azar

Enmascaramiento

Enmascaramiento simple

Qué evalúan los investigadores

Estas medidas indican qué se estudia. No prueban que un tratamiento funcione.

Medidas principales

Medidas secundarias

Centros de investigación (1)

El estado general puede diferir del estado de un centro. Confirma la disponibilidad antes de trasladarte.

1 centros

Equipo y fechas

Patrocinador principal

National Institute on Drug Abuse (NIDA)

Inicio del estudio

15 nov 2026 Estimado

Finalización primaria

14 jul 2035 Estimado

Finalización del estudio

14 jul 2035 Estimado

Primera publicación

1 ago 2025 Real

Última actualización

10 nov 2026 Real

Contactos oficiales del estudio