Low Intensity Focused Ultrasound Pulses (LIFUP) to Modulate Pain

The anterior nuclei of the thalamus in addition to periaqueductal gray (PAG) and rostral ventromedial medulla (RVM) are integral regions of a supraspinal opioidergic structure that regulate pain perception. With the capability to influence deep neurological tissues, low intensity frequency ultrasound pulsation (LIFUP) can likely modulate this circuit and induce analgesia. LIFUP deep brain modulation is achieved by induction of focused mechanical waveforms that traverse the cranium and underlying brain tissue. The low frequency of the ultrasonic wave consequently alters neuronal transmission and causes action potential variations through mechanical means, rather than thermal. The purpose of this study is to examine whether stimulation of the anterior nuclei of the thalamus via LIFUP induces analgesia. We hypothesize that suppression of the anterior nuclei of the thalamus will induce a temporary increase in pain tolerance. Moreover, the behavioral changes in pain will correlate with specific regional BOLD changes during pain.