Fig. 4

Ultrasonic stimulation (left) and magnetic stimulation (right) in non-invasive manner. a Schematic figure of focused ultrasound. b Schematic figure of In vivo experimental setup for induced EMG recording in rats using ultrasound. c Schematic figure of StimDust system to stimulate a sciatic nerve in a rat. d Schematic figure diagram of transcranial magnetic stimulation (TMS); A magnetic field that occurs in a coil above the head induces an eddy current that stimulates the nerve. e-f Schematic of the microfabricated coil (bottom). Coils were inserted into the whisker motor cortex (upper). Measurement of electric field gradients in coil using simulation. Surface plot of the electric field gradients in the x direction (left). Two- dimensional profile of the gradients in the vertical and horizontal directions (right). g Illustration of simulation result indicating the threshold of peripheral nerve stimulation during MRI measurement. h Illustration of magnetic stimulation of a sciatic nerve in a rat. The coil was positioned onto the exposed sciatic nerve