Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA.
Electrical & Computer Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.
Commun Biol. 2024 Sep 2;7(1):1076. doi: 10.1038/s42003-024-06728-y.
Temporal interference (TI) stimulation is a popular non-invasive neurostimulation technique that utilizes the following salient neural behavior: pure sinusoid (generated in off-target brain regions) appears to cause no stimulation, whereas modulated sinusoid (generated in target brain regions) does. To understand its effects and mechanisms, we examine responses of different cell types, excitatory pyramidal (Pyr) and inhibitory parvalbumin-expressing (PV) neurons, to pure and modulated sinusoids, in intact network as well as in isolation. In intact network, we present data showing that PV neurons are much less likely than Pyr neurons to exhibit TI stimulation. Remarkably, in isolation, our data shows that almost all Pyr neurons stop exhibiting TI stimulation. We conclude that TI stimulation is largely a network phenomenon. Indeed, PV neurons actively inhibit Pyr neurons in the off-target regions due to pure sinusoids (in off-target regions) generating much higher PV firing rates than modulated sinusoids in the target regions. Additionally, we use computational studies to support and extend our experimental observations.
时频干扰（TI）刺激是一种流行的非侵入性神经刺激技术，利用以下显著的神经行为：纯正弦波（在非目标脑区产生）似乎不会引起刺激，而调制正弦波（在目标脑区产生）则会。为了了解其作用机制，我们研究了不同细胞类型（兴奋性锥体神经元和表达抑制性 Parvalbumin 的神经元）对纯正弦波和调制正弦波的反应，包括在完整网络中和孤立状态下的反应。在完整网络中，我们提供的数据表明，PV 神经元比 Pyr 神经元更不容易表现出 TI 刺激。值得注意的是，在孤立状态下，我们的数据表明，几乎所有的 Pyr 神经元都停止表现出 TI 刺激。我们得出结论，TI 刺激主要是一种网络现象。事实上，由于纯正弦波（在非目标区域）产生的 PV 放电率比目标区域中的调制正弦波高得多，因此 PV 神经元在非目标区域中主动抑制 Pyr 神经元。此外，我们还使用计算研究来支持和扩展我们的实验观察。
