In the randomized, sham-controlled study, 10 patients with schizophrenia or schizoaffective disorder received both the ultrasound treatment and a placebo treatment, spaced one week apart. The technique uses a device placed on the head to deliver ultrasound waves through the skull to a targeted brain region.
The researchers focused the beam on the right globus pallidus internus, part of the cortico-striatal-pallido-thalamic circuit that has been linked to schizophrenia symptoms. In surveys after each session, patients reported less severe delusions, with weaker conviction and less stress, in the week after real stimulation compared with placebo. The treatment did not significantly change auditory hallucinations or overall cognition.
Side effects were mild, mainly fatigue and headache. Some patients had transient increases in delusions, but these were just as common after placebo, suggesting they reflected normal fluctuations in symptoms.
Study co-author Dr. Donald Goff, a professor of psychiatry at NYU Grossman, called the results exciting but preliminary. "It's too early to know for certain what the therapeutic benefits will be, but it's very exciting," he told Live Science.
The approach differs from other noninvasive brain stimulation methods, such as transcranial magnetic stimulation, because ultrasound can penetrate deeper into the brain with greater specificity, said co-author Shy Shoham, a neural engineer at NYU Grossman. Dr. Deepak Sarpal of the University of Pittsburgh School of Medicine, who was not involved in the study, noted that ultrasound reaches deep regions in a less invasive way than deep brain stimulation, which requires a surgeon to implant an electrode.
The team's hypothesis, said co-author Dr. Wei Qi, is that schizophrenia involves an imbalance between excitation and inhibition in how the brain decides what matters. "The failure to inhibit irrelevant signals could be the basis of psychosis," he said.
The researchers plan to test the technique in more patients and experiment with different ultrasound doses. Earlier this year, a separate group reported that stimulating portions of the striatum eased hallucinations in schizophrenia patients for at least a week.