This study investigates the causal effects of low-intensity transcranial focused ultrasound (tFUS) on odor valence perception and odor-elicited avoidance behaviors in healthy adults. Participants undergo sham and active tFUS targeting the amygdala (AMYG) and ventral striatal olfactory tubercle (VSOT) in a within-subject, randomized, sham-controlled crossover design. Outcomes include subjective odor ratings and objective neurophysiological and behavioral indices of odor valence processing. This research is exploratory and mechanistic in nature and is not intended to evaluate clinical safety or therapeutic efficacy.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
TRIPLE
Enrollment
28
non-invasive brain stimulation using tFUS
Odor Valence Rating
Participant rating of odor pleasantness on a 0-100 mm visual analog scale (e.g., unpleasant → pleasant)
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
Late Positive Potential
Mean EEG amplitude (400-800 ms) at centro-parietal sites to olfactory-visual stimuli
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
Sniff Volume
Total nasal airflow (in mL) per odor trial, measured via nasal cannula or spirometer
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
Corrugator Supercilii EMG Activity
Mean EMG amplitude from facial muscle sensitive to negative affect and aversion
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
Odor Intensity Rating
Participant rating of odor intensity on a 0-100 mm visual analog scale (e.g., not at all → extremely)
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
Odor Avoidance Rating
Participant rating of their desire to avoid the odor on a 0-100 mm visual analog scale (e.g., "not at all" → "extreme")
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
Sniff Rate
Breaths per min or per trial window in response to odor exposure
Time frame: from the baseline visit until the third follow-up visit (about 1 month)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.