{Reference Type}: Journal Article
{Title}: Abnormalities of the Descending Inhibitory Nociceptive Pathway in Functional Motor Disorders.
{Author}: Squintani G;Geroin C;Pasquali A;Cavazzana E;Segatti A;Lippolis M;Bonetto C;Antelmi E;Tinazzi M;
{Journal}: Mov Disord
{Volume}: 39
{Issue}: 5
{Year}: 2024 May 12
{Factor}: 9.698
{DOI}: 10.1002/mds.29770
{Abstract}: <B>BACKGROUND: </B>Pain is a common disabling non-motor symptom affecting patients with functional motor disorders (FMD).<BR><B>OBJECTIVE: </B>We aimed to explore ascending and descending nociceptive pathways with laser evoked potentials (LEPs) in FMD.<BR><B>METHODS: </B>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.<BR><B>RESULTS: </B>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.<BR><B>CONCLUSIONS: </B>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.