Transcranial ultrasound stimulation selectively enhances fronto-temporal context-guided memory
There is substantial scientific interest in advancing knowledge on the control mechanisms supporting adaptive memory and improving approaches that can enhance cognition through brain stimulation. We implemented a non-invasive focal Transcranial Ultrasound Stimulation (TUS) approach with known longer-lasting post-stimulation effects in two rhesus macaques performing a novel context-dependent memory-sequencing task implemented on multiple touchscreens within their home units. Consistently in both monkeys, TUS to the anterior, but not posterior, medial temporal lobe enhanced performance under stable memory-sequencing contexts. TUS to the medial prefrontal cortex, on the other hand, selectively improved performance when contexts were unstable and the monkey needed to adapt to both a change in context and temporal sequence. These findings provide positive causal evidence of a functional dissociation within fronto-temporal memory circuits and pave the way for advancing non-invasive approaches to improve cognitive function and the study of neural circuits under focal enhancement across species. IMPACT STATEMENTTranscranial ultrasound stimulation of the prefrontal-hippocampal network selectively enhances context-guided memory in macaques, demonstrating that non-invasive brain stimulation can causally improve, rather than only disrupt, memory circuits.