Neurology and Neurophysiology Unit, Azienda Ospedaliera Universitaria Integrata, Verona, Italy.
Neurology Unit, Movement Disorders Division, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
Mov Disord. 2024 May;39(5):905-910. doi: 10.1002/mds.29770. Epub 2024 Mar 12.
Pain is a common disabling non-motor symptom affecting patients with functional motor disorders (FMD).
We aimed to explore ascending and descending nociceptive pathways with laser evoked potentials (LEPs) in FMD.
We studied a "bottom-up and top-down" noxious paradigm applying a conditioned pain modulation (CPM) protocol and recorded N2/P2 amplitude in 21 FMD and 20 controls following stimulation of both right arm and leg at baseline (BS) (bottom-up), during heterotopic noxious conditioning stimulation (HNCS) with ice test (top-down) and post-HNCS.
We found a normal ascending pathway, but reduced CPM response (lower reduction of the N2/P2 amplitude) in FMD patients, by stimulating both upper and lower limbs. The N2/P2 amplitude ratio*100 (between the HNCS and BS) was significantly higher in patients with FMD than HC.
Our results suggest that pain in FMD possibly reflects a descending pain inhibitory control impairment, therefore, providing a novel venue to explore the pathophysiology of pain in FMD. © 2024 International Parkinson and Movement Disorder Society.
疼痛是一种常见的致残性非运动症状，影响功能性运动障碍（FMD）患者。
我们旨在通过激光诱发电位（LEP）探索 FMD 中的上行和下行伤害性通路。
我们研究了一种“自上而下和自下而上”的伤害性范式，应用条件疼痛调制（CPM）方案，并在基线（BS）时（自下而上）、在使用冰试验的异源性伤害性调节刺激（HNCS）期间（自上而下）和 HNCS 后记录 21 名 FMD 患者和 20 名对照者的右侧上肢和下肢的 N2/P2 振幅。
我们发现，通过刺激上下肢，FMD 患者的上行通路正常，但 CPM 反应（N2/P2 振幅降低）降低。FMD 患者的 N2/P2 振幅比*100（HNCS 与 BS 之间）明显高于 HC。
我们的结果表明，FMD 中的疼痛可能反映了下行疼痛抑制控制的损伤，因此为探索 FMD 中的疼痛病理生理学提供了新的途径。© 2024 国际帕金森病和运动障碍学会。
