Study: NCT05048862

Intervention type: DIAGNOSTIC_TEST
Intervention: Contact heat evoked potentials
Description: A contact heat evoked potential stimulator (Medoc, Ramat Yishai, Israel) will be used for delivering heat stimulation. Stimuli will be delivered repeatedly to the same stimulation site and the inter-stimulus interval will be randomly set to around 18\~22 s. CHEP will be recorded using a Nicolet Bravo evoked potential system (Nicolet Biomedical, Madison, WI). The recording electrode was placed at the Cz and P3 of international 10-20 system. The impendence of all recording electrodes was kept below 3 kΩ. The evoked potentials were filtered with a bandpass filter at 0.1\~30 Hz. Recording was triggered by the onset of each stimulus, and the sweep time was 1500 ms.

Intervention type: DIAGNOSTIC_TEST
Intervention: Nerve excitability study
Description: Nerve excitability studies will be undertaken on the median, tibial, peroneal and sural nerves as per previously detailed protocols. Skin temperature will be monitored at the site of stimulation and was maintained at \>32°C. Stimulation and recording will be controlled by automated computerized system (QTRAC; Institute of Neurology, London, U.K.) and the stimulus current will be administered using an isolated linear bipolar constant-current stimulator (DS5; Digitimer, Welwyn Garden City, U.K.). Responses will be amplified (ICP511 AC amplifier, Grass Technologies, West Warwick, USA) with electronic noise removed (Hum Bug 50/60 Hz Noise Eliminator, Quest Scientific Instruments, North Vancouver, Canada).

Intervention type: DIAGNOSTIC_TEST
Intervention: Nerve excitability study
Description: Nerve excitability studies will be undertaken on the median, tibial, peroneal and sural nerves as per previously detailed protocols. Skin temperature will be monitored at the site of stimulation and was maintained at \>32°C. Stimulation and recording will be controlled by automated computerized system (QTRAC; Institute of Neurology, London, U.K.) and the stimulus current will be administered using an isolated linear bipolar constant-current stimulator (DS5; Digitimer, Welwyn Garden City, U.K.). Responses will be amplified (ICP511 AC amplifier, Grass Technologies, West Warwick, USA) with electronic noise removed (Hum Bug 50/60 Hz Noise Eliminator, Quest Scientific Instruments, North Vancouver, Canada).

Intervention type: DIAGNOSTIC_TEST
Intervention: Transcranial magnetic stimulation (TMS)
Description: In simple rTMS protocols, individual stimuli are spaced apart by identical interstimulus intervals (ISI). The stimulation protocol was in accordance with published safety recommendations. The patterned rTMS protocols included (1) Theta burst stimulation, (2) Repetitive paired-pulse TMS. All the above stimulation protocols or paradigms will follow the international guideline of the use of TMS in clinical practice and research (Rossi et al., 2009; Fitzgerald and Daskalakis, 2012; Groppa et al., 2012; Steeves et al., 2012).

Intervention type: DIAGNOSTIC_TEST
Intervention: Transcranial magnetic stimulation (TMS)
Description: In simple rTMS protocols, individual stimuli are spaced apart by identical interstimulus intervals (ISI). The stimulation protocol was in accordance with published safety recommendations. The patterned rTMS protocols included (1) Theta burst stimulation, (2) Repetitive paired-pulse TMS. All the above stimulation protocols or paradigms will follow the international guideline of the use of TMS in clinical practice and research (Rossi et al., 2009; Fitzgerald and Daskalakis, 2012; Groppa et al., 2012; Steeves et al., 2012).

Intervention type: DIAGNOSTIC_TEST
Intervention: fMRI acquisition and image analysis
Description: fMRI will be performed on a 3-T MR machine (Trio; Siemens, Erlangen, Germany). Each subject's head will be positioned comfortably inside a receive-only 8-channel birdcage head coil, supplied with ear plugs, heavily padded and secured with a strap across the forehead in order to minimize head motion. All data will be processed using SPM2 (Wellcome Department of Cognitive Neurology, London UK) 36 implemented on MATLAB (Mathworks Inc. Sherborn, MA).

Intervention type: DIAGNOSTIC_TEST
Intervention: fMRI acquisition and image analysis
Description: fMRI will be performed on a 3-T MR machine (Trio; Siemens, Erlangen, Germany). Each subject's head will be positioned comfortably inside a receive-only 8-channel birdcage head coil, supplied with ear plugs, heavily padded and secured with a strap across the forehead in order to minimize head motion. All data will be processed using SPM2 (Wellcome Department of Cognitive Neurology, London UK) 36 implemented on MATLAB (Mathworks Inc. Sherborn, MA).