Open AccessEffect of transcranial direct current stimulation in the first weeks after stroke: a preliminary study
Author(s) -
Marcela Tengler Carvalho Takahashi,
Paulo Rodrigo Bazán,
Joana Bisol Balardin,
Danielle de Sá Boasquevisque,
Edson Amaro Júnior,
Adriana Bastos Conforto
Publication year - 2021
Language(s) - English
Resource type - Conference proceedings
DOI - 10.5327/1516-3180.252
Subject(s) - transcranial direct current stimulation , motor cortex , primary motor cortex , stroke (engine) , premotor cortex , physical medicine and rehabilitation , psychology , randomized controlled trial , rank correlation , transcranial magnetic stimulation , stimulation , medicine , physical therapy , neuroscience , anatomy , mechanical engineering , dorsum , machine learning , computer science , engineering
Background: There is limited information about effects of transcranial Direct Current Stimulation(tDCS), delivered within the first weeks post-stroke, on performance of the paretic upper limb and on connectivity between motor areas in the affected and unaffected hemispheres. Objectives: We compared changes in Fugl-Meyer Assessment of Motor Recovery(FMA) scores, connectivity between the primary motor cortex of the unaffected(M1UH) and the affected hemisphere(M1AH), as well as between M1UH and the premotor cortex of the unaffected hemisphere(PMUH) before and after 6 sessions of cathodal tDCS targeting the primary motor cortex of the unaffected hemisphere(M1UH) early after stroke in 13 patients. Methods: This hypothesis-generating substudy was a randomized parallel, two-arm, double-blind, sham-controlled clinical trial performed at the Albert Einstein Hospital. Subjects were randomized active(N=6) or sham(N=7) groups. Results: Clinically relevant differences in FMA scores(≥ 9 points) were observed more often in the sham than in the active group. Between-group differences in changes in FMA scores were not statistically significant(Mann-Whitney test, p=0.133) but the effect size was -0.619(rank biserial correlation). Connectivity measures(Fisher’s z- transform of ROI-to-ROI correlations) between M1AH-M1UH increased in 5/6 participants in the active, and in 2/7 in the sham group after treatment. Between-group differences in changes in connectivity(M1UH-M1AH or PMUH-M1AH) were not statistically significant. In contrast with M1AH-M1UH connectivity, improvements in motor performance were more frequent in the active than in the sham group. Conclusions: Effects of cathodal tDCS on motor performance and on Resting-state Functional Magnetic Resonance Imaging may have distinct underpinnings in subjects at an early stage after stroke.