Low-intensity Focused Ultrasound and Autonomic Response

Studying the effects of Low Intensity Focused Ultrasound (LIFU) to the dorsal anterior insula (dAI) and dorsal anterior cingulate cortex (dACC) on autonomic control using three tests to probe the autonomic system. A cold pressor task, valsalva maneuver, and deep breathing tasks will be performed pre and post LIFU application. Physiologic recordings will be recorded throughout.

Characterize the effect of LIFU to the bilateral dorsal anterior insula (dAI) and dorsal anterior cingulate cortex (dACC)) on autonomic control. The dAI is a critical brain area involved in autonomic function with evidence suggesting the right vs left dAI contribute differently to autonomic control, preferentially processing sympathetic and parasympathetic processing, respectively. Similarly, the dACC has been strongly implicated in autonomic control and works with the insula for autonomic processing. Inconveniently, these brain regions lie deep to the cortex, prohibiting access using conventional noninvasive methods like transcranial magnetic stimulation (TMS). LIFU can be focused at depth to reach the insula and ACC with high spatial precision. However, the effect of LIFU to the human dAI and dACC on autonomic control is unknown. To address this, the investigators will target the bilateral dAI and the dACC to assess how LIFU to each of these areas affects subjective report to different safe, reproducible autonomic challenges. These tasks are a cold pressor task, valsalva maneuver, and a deep breathing task.

ultrasound transducer applying low intensity waveforms to targeted brain regions for neuromodulation.

Inclusion Criteria: Does not meet exclusion criteria. Exclusion Criteria: The exclusion criteria below are regularly implemented in MRI, CT, and EEG experiments for the safety of the subjects and for data quality assurance. Claustrophobia (scanning environment may be uncomfortable). Contraindications to MRI: including pacemaker, aneurysm clips, neurostimulators, cochlear implants, metal in eyes, steel worker, or other implants. Contraindications to CT: pregnancy Active medical disorder or treatment with potential central nervous system (CNS) effects (e.g. Alzheimer's) - History of neurologic disorder. (e.g. Parkinson's, Epilepsy, or Essential Tremor) History of head injury resulting in loss of consciousness for >10 minutes. History of alcohol or drug dependence (through self-report). History of cardiac disease