Stimulation of Neurons and Astrocytes via Temporally Interfering Electric Fields

A novel non-invasive electrical stimulation method, temporal interference stimulation (TIS), has been proposed to enable spatially steerable stimulation and to selectively activate different brain regions. However, TIS has not been studied with cell cultures that can provide an indepth assessment of its effects on neuronal cells. We successfully established an in vitro TIS setup using rat cortical neurons on microelectrode arrays. Stimulations involved 1) TIS with 653 Hz and 643 Hz, resulting in a 10 Hz frequency envelope, 2) low-frequency stimulation (LFS) at 10 Hz, 3) high-frequency stimulation (HFS) at 653 Hz, and 4) no electrical stimulation (control/sham). HFS and LFS had the least effect on neuronal activity, but TIS elicited neuronal electrophysiological responses, especially 24 hours after stimulation. We also assessed TIS in neuron-astrocyte co-cultures. Interestingly, co-cultures seemed to counteract the TIS effects. Hence, our findings deepen the current understanding of the electrical modulation of neurons during TIS. HighlightsO_LITemporal interference stimulation (TIS) is a new technique for brain stimulation. C_LIO_LITIS setup was established and combined with microelectrode array (MEA) system. C_LIO_LIRat cortical neurons and astrocytes were stimulated with TIS in vitro. C_LIO_LINeurons responded to TIS more prominently without astrocyte support. C_LI