Functional abnormalities of the globus pallidus interna (GPi) are associated with psychosis severity and treatment response in schizophrenia. A randomized, sham-controlled pilot study investigated whether MRI-guided transcranial ultrasound stimulation (TUS) of the right GPi could improve psychotic symptoms in 10 patients (mean age, 37.5 years) with schizophrenia or schizoaffective disorder and persistent psychosis. Participants underwent a single 10-minute active TUS session and a sham session one week apart.

Delusion Experience Sampling Assessment (DESA) scores decreased by a mean of 1.2 points after TUS, compared with a 0.4-point increase after sham. Mixed-effects analysis showed a significantly greater reduction in DESA scores with TUS than with sham stimulation (estimated treatment effect, −1.56; 95% CI, −2.54 to −0.58; p = 0.002). However, no significant differences were observed…