New Study - Neurochemical and functional connectivity effects of theta-burst TUS.

A recent study published in Nature Communications by a team of researchers from the Nuffield Department of Clinical Neurosciences at the University of Oxford, delves into the neurochemical and functional connectivity effects of theta-burst TUS, a specific TUS protocol known to enhance corticospinal excitability. The study, conducted in a group of 24 healthy volunteers, aimed to elucidate the mechanisms underlying TUS-mediated neuroplasticity in deep cortical regions.

The study's findings shed light on the neurochemical basis of TUS's effects. By measuring gamma-aminobutyric acid (GABA), a primary inhibitory neurotransmitter, the researchers observed a selective reduction in GABA levels following theta-burst TUS in the posterior cingulate cortex (PCC), a deep cortical region associated with self-awareness, memory, and attention. This reduction in GABA suggests a shift in the balance between excitation and inhibition, potentially contributing to the observed changes in brain activity induced by TUS.

The study further examined the functional connectivity, or the interplay between brain regions, before and after TUS. Interestingly, both the PCC and dorsal anterior cingulate cortex (dACC), another deep cortical region linked to emotion and decision-making, exhibited increased functional connectivity following TUS. This enhanced connectivity suggests that TUS may promote communication and coordination between these distinct brain regions.

The findings of this study have significant implications for potential therapeutic applications of TUS in mental health conditions. The observed reduction in GABAergic inhibition and enhanced functional connectivity could potentially be beneficial in disorders characterised by hyperactivity or dysregulation of these neural mechanisms. For instance, TUS may hold promise in the treatment of conditions like anxiety, depression, and addiction.