Test-retest reliability of intrahemispheric dorsal premotor and primary motor cortex dual-site TMS connectivity measures

• Published in: Clinical neurophysiology 2024-09, Vol.165, p.64-75
• Main Authors: Heemels, Robin E., Ademi, Sian, Hehl, Melina
• Format: Article
• Language: English
• Subjects: Adult; Dorsal premotor cortex (PMd); Dual-site TMS (dsTMS); Effective connectivity; Electromyography - methods; Evoked Potentials, Motor - physiology; Female; Humans; Intrahemispheric interaction; Male; Motor Cortex - physiology; Neural Inhibition - physiology; Reliability; Reproducibility of Results; Transcranial magnetic stimulation (TMS); Transcranial Magnetic Stimulation - methods; Transcranial Magnetic Stimulation - standards; Young Adult
• ISSN: 1388-2457; 1872-8952; 1872-8952
• DOI: 10.1016/j.clinph.2024.06.006

[Display omitted] •The stacked-coil dsTMS setup could reliably explore PMd–M1 connectivity for certain ISIs ranging from 3 to 10 ms.•Intrahemispheric PMd–M1 connectivity was inhibitory for ISIs of 3 and 5 ms, and facilitatory for 10 ms.•Replication of SICI and ICF paradigms with the stacked-coil setup achieved test–retest reliability comparable to the literature. Investigating the optimal interstimulus interval (ISI) and the 24-hour test–retest reliability for intrahemispheric dorsal premotor cortex (PMd) – primary motor cortex (M1) connectivity using dual-site transcranial magnetic stimulation (dsTMS). In 21 right-handed adults, left intrahemispheric PMd–M1 connectivity has been investigated with a stacked-coil dsTMS setup (conditioning stimulus: 75% of resting motor threshold; test stimulus: eliciting MEPs of 1–1.5 mV) at ISIs of 3, 5–8, and 10 ms. Additionally, M1–M1 short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) were investigated to assess comparability to standard paired-pulse setups. Conditioning PMd led to significant inhibition of M1 output at ISIs of 3 and 5 ms, whereas 10 ms resulted in facilitation (all, p