Biology subjects

Rannaud Monany, D.

Publications and source records attributed to Rannaud Monany, D..

3 recordsLinked to original sources

bioRxiv2022

Optimizing the Benefits of Mental Practice on Motor Acquisition and Consolidation with Moderate-Intensity Aerobic Exercise

The optimization of mental practice (MP) protocols matters for sport and motor rehabilitation. In this study, we were interested in the benefits of moderate-intensity exercise in MP, given its positive effects on the acquisition and consolidation of motor skills induced by physical practice (PP). Four experimental groups were tested: i) physical practice without exercise (PP-Rest), ii) mental practice without exercise (MP-Rest), iii) mental practice preceded by Exercise (Exe-MP), and iv) mental practice followed by Exercise (MP-Exe). We hypothesized that exercise before MP would further increase speed and accuracy at a finger-sequence task measured right after MP (potentiation of motor acquisition), whereas exercise after MP would further increase speed and accuracy the day after MP (promotion of motor consolidation). Motor performance (movement speed and accuracy) was measured during a sequential finger tapping task before (Pre-Test), immediately after (Post-Test 0h, acquisition), and one day after practice (Post-Test 24h, consolidation). Results suggest that exercise before MP did not additionally improve motor acquisition in comparison to the MP-Rest group (both for accuracy and speed, ps>0.05). Interestingly, moderate-intensity exercise after MP further increased performance during motor consolidation (speed, p=0.051; accuracy, p=0.028), at the level of the PP-Rest group. This novel finding represents a promising advance in the optimization of mental practice protocols in sport-related and rehabilitation settings.

neuroscience↗

bioRxiv2021

Smoothness discriminates physical from motor imagery practice of arm-reaching movements.

Physical practice (PP) and motor imagery practice (MP) lead to the execution of fast and accurate arm movements. However, there is currently no information about the influence of MP on movement smoothness, nor about which performance parameters best discriminate these practices. In the current study, we assessed motor performances with an arm pointing task with constrained precision before and after PP (n= 15), MP (n= 15), or no practice (n= 15). We analyzed gains between Pre- and Post-Test for five performance parameters: movement duration, mean and maximal velocities, total displacements, and the number of velocity peaks characterizing movement smoothness. The results showed an improvement of performance after PP and MP for all parameters, except for total displacements. The gains for movement duration, and mean and maximal velocities were statistically higher after PP and MP than after no practice, and comparable between practices. However, motor gains for the number of velocity peaks were higher after PP than MP, suggesting that movements were smoother after PP than after MP. A discriminant analysis also identified the number of velocity peaks as the most relevant parameter that differentiated PP from MP. The current results provide evidence that PP and MP specifically modulate movement smoothness during arm reaching tasks. This difference may rely on online corrections through sensory feedback integration, available during PP but not during MP.

neuroscience↗

bioRxiv2021

Mental practice modulates functional connectivity between the cerebellum and the primary motor cortex.

Our brain has the extraordinary capacity to improve motor skills through mental practice. Conceptually, this ability is attributed to internal forward models, which are neural networks that can predict the sensory consequences of motor commands. While the cerebellum is considered as a potential locus of internal forward models, evidence for its involvement in mental practice is missing. In our study, we employed single and dual transcranial magnetic stimulation technique to probe the level of corticospinal excitability and of cerebellar-brain inhibition, respectively, before and after a mental practice session or a control session. Motor skills (i.e., accuracy and speed) were measured using a sequential finger tapping-task. Here, we show that mental practice enhances both speed and accuracy. In parallel, the functional connectivity between the cerebellum and the primary motor cortex changes, with less inhibition from the first to the second, expressing the existence of neuroplastic changes within the cerebellum after mental practice. These findings reveal that the corticocerebellar loop is a major neural circuit for skill improvement after mental practice.

neuroscience↗