AUTHOR=Meigal Alexander Yu. , Tretjakova Olesya G. , Gerasimova-Meigal Liudmila I. , Sayenko Irina V. 

TITLE=Program of Seven 45-min Dry Immersion Sessions Improves Choice Reaction Time in Parkinson’s Disease

JOURNAL=Frontiers in Physiology

VOLUME=Volume 11 - 2020

YEAR=2021

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2020.621198

DOI=10.3389/fphys.2020.621198

ISSN=1664-042X

ABSTRACT=The study hypothesis held that in subjects with Parkinson's disease (PD) the reaction time (RT) tests of the higher cognition demand would have more readily improved under the program of analog microgravity (μG) modeled with "dry" immersion (DI). To test this hypothesis, 10 subjects with PD have passed through a program of 7 DI sessions (each 45 min long) within 25-30 days, with overall μG dose 5¼ hours. Five patients were enrolled as controls, without DI (noDI group). Simple (SRT), disjunctive (DRT), and choice reaction time (CRT) were assessed in 4 study points: before the program of DI (preDI), one day (postDI), 2 weeks (DI2w), and 2 months (DI2m) after it. The motor time (MT) was assessed with the tapping test. Additionally, signal detection time (SDT) and central processing time (CPT) were extracted from the data. Before the program of DI, the RT tests have lined in accordance with their cognition load: SRT (284±37 ms), DRT (338±38 ms), and CRT (540±156 ms). In accordance with hypothesis, CRT and DRT have improved under DI by, correspondingly, 20 and 8% at the study point "DI2w", while SRT, SDT and MT did not change (< 5% to the preDI point, p>0,05). Thus, the program of DI provoked RT improvement specifically in the cognitively loaded tasks, in a "dose of cognition-reaction" manner. The accuracy of reaction has changed in none of the RT tests. The neurophysiologic, hormonal/neuroendocrine, behavioral, neural plasticity and acclimation mechanisms may have contributed to such result.