Asmolova Anastasiia, Sukmanova Anastasiia, Makarova Milana, Novikov Pavel, Nikulin Vadim, Nazarova Maria
Max Planck School of Cognition, Leipzig, Germany.
Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Brain Topogr. 2025 Jul 30;38(5):55. doi: 10.1007/s10548-025-01128-9.
Although the interstimulus interval (ISI) is one of the crucial parameters in the transcranial magnetic stimulation (TMS), the ISI effect on the results of the TMS motor mapping is usually overlooked. This study explored the influence of ISI, ranging from 1.5 to 41 s, on multi-muscle navigated TMS (nTMS) motor mapping results. Twenty-six healthy male volunteers underwent four nTMS motor mapping sessions on two separate days. We mapped the muscles' cortical representations (MCRs) of the five upper limb muscles: abductor pollicis brevis (APB), abductor digiti minimi (ADM), first dorsal interosseous (FDI), extensor digitorum communis (EDC), and biceps brachii (BB). We estimated the relationship between ISIs and trial-to-trial motor evoked potentials (MEPs) amplitudes and MCR areas. In addition, we accounted for the association between the ISI and TMS mapping procedure parameters such as the distance between the successive stimulation points, the number of stimuli in a TMS session, and the stimulus counting number. A weak positive association was observed between: (1) trial-to-trial ISI and MEP amplitude and (2) median ISI and MCR areas. We recommend reporting ISI values in TMS motor mapping studies and monitoring the impact of ISI on MEP amplitudes.
尽管刺激间隔（ISI）是经颅磁刺激（TMS）的关键参数之一，但ISI对TMS运动映射结果的影响通常被忽视。本研究探讨了1.5至41秒的ISI对多肌肉导航TMS（nTMS）运动映射结果的影响。26名健康男性志愿者在两天内分别接受了四次nTMS运动映射测试。我们绘制了五块上肢肌肉的皮质代表区（MCR）：拇短展肌（APB）、小指展肌（ADM）、第一背侧骨间肌（FDI）、指总伸肌（EDC）和肱二头肌（BB）。我们估计了ISI与逐次试验运动诱发电位（MEP）振幅和MCR面积之间的关系。此外，我们还考虑了ISI与TMS映射程序参数之间的关联，如连续刺激点之间的距离、TMS测试中的刺激次数以及刺激计数。在以下两者之间观察到弱正相关：（1）逐次试验的ISI与MEP振幅，以及（2）中位数ISI与MCR面积。我们建议在TMS运动映射研究中报告ISI值，并监测ISI对MEP振幅的影响。
