Abstract：Peripheral nerve electrical stimulation can be used for sports rehabilitation and chronic neuralgia treatment, but the current spatially selective non-invasive stimulation remains a problem to be solved. A non-invasive peripheral nerve electrical stimulation method that features a certain level of selectivity was developed based on the temporally interfering (TI) electric field. The rat sciatic nerve was tested and the stimulating electrodes were arranged in the direction parallel to the nerve on the ventral and dorsal skin of the thigh. The TI stimulation peak was localized to the nerve for selective stimulation by the scan of interfering electric field. The results showed that optimal electrical parameters, through which the electrical field was delivered to the nerve, could be acquired by scanning without knowing the exact location of the nerve in advance. Thus, selective non-invasive stimulation of nerves could be achieved and the control of the intensity of stimulation could be realized under the premise of keeping the stimulation focus fixed. On this basis, the stimulation threshold IT of TI electric field on rat sciatic nerve was explored and IT of different conditions were measured as well, including fixing frequency difference Δf=0.5 Hz (n=12), changing the frequency f=1～6 kHz and fixed f=5 kHz (n=11), changing the frequency difference Δf=0.5～10 Hz, at the same time, compared with that of equal amplitude kHz electric field (n=7). The results demonstrated that the IT of the equal-amplitude kHz electric field is significantly higher than that of the TI electric field (P<0.05), and there is a significant difference in the IT at different frequencies f(P<0.05), while no remarkable difference in the IT of different Δf(P<0.05), which was different between two frequencies, was observed, indicating that the stimulation threshold of TI electric field on rat sciatic nerve was affected by frather thanΔf, and the stimulation threshold IT was proportional to the frequency f.
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