Fig. 1

Nonthermal effects of MIRS on neuronal excitability. (A) Configuration for temperature measurement using a carbon fiber (diameter: 7 ?m; naked length: 20 ?m). The cladding diameter of the MIRS fiber is 170 ?m. (B, Left) Change of the measured currents as the bath cools down from ?45 to 25 °C. (B, Right) Arrhenius plot of the carbon fiber current (I, pA) versus the temperature (T, absolute temperature). (B, Inset) An example current trace of the carbon fiber induced by MIRS at 70 ?m away. (C) Measured temperature before and during MIRS. (D) A two-dimensional heatmap of temperature change. Note the direction of the bath flow. (E, Top) Schematic illustration of MIRS and whole-cell recording from a PC in a prefrontal cortex slice. (E, Bottom) Example V_m responses to negative current pulses (500 ms in duration). Blue, control (Ctrl); orange, MIRS. (F) Representative spiking responses to positive current pulses. Note the decrease and increase in AP frequency with small and large current pulses, respectively. (G) Comparison of I?F curves (Left) and slopes (Right) before and during MIRS at 300 ?m away from the cell. (H) Group data showing changes in resting V_m, R_in, membrane time constant ?, and rheobase current upon MIRS at 300 ?m. *P < 0.05, **P < 0.01, and ***P < 0.001. Paired Student?s t test. Error bars represent SEM.