Motor Training Task Research Articles

Revolutionizing motor dysfunction treatment: A novel closed-loop electrical stimulator guided by multiple motor tasks with predictive control

Functional electrical stimulation (FES) has been demonstrated as a viable method for addressing motor dysfunction in individuals affected by stroke, spinal cord injury, and other etiologies. By eliciting muscle contractions to facilitate joint movements, FES plays a crucial role in fostering the restoration of motor function compromised nervous system. In response to the challenge of muscle fatigue associated with conventional FES protocols, a novel biofeedback electrical stimulator incorporating multi-motor tasks and predictive control algorithms has been developed to enable adaptive modulation of stimulation parameters. The study initially establishes a Hammerstein model for the stimulated muscle group, representing a time-varying relationship between the stimulation pulse width and the root mean square (RMS) of the surface electromyography (sEMG). An online parameter identification algorithm utilizing recursive least squares is employed to estimate the time-varying parameters of the Hammerstein model. Predictive control is then implemented through feedback corrections based on the comparison between predicted and actual outputs, guided by an optimization objective function. The integration of predictive control and roll optimization enables closed-loop control of muscle stimulation. The motor training tasks of elbow flexion and extension, wrist flexion and extension, and five-finger grasping were selected for experimental validation. The results indicate that the model parameters were accurately identified, with a RMS error of 3.83 % between actual and predicted values. Furthermore, the predictive control algorithm, based on the motor tasks, effectively adjusted the stimulus parameters to ensure that the stimulated muscle groups can achieve the desired sEMG characteristic trajectory. The biofeedback electrical stimulator that was developed has the potential to assist patients experiencing motor dysfunction in achieving the appropriate joint movements. This research provides a foundation for a novel intelligent electrical stimulation model.

Influences of Aerobic Exercise on Motor Sequence Learning and Corticomotor Excitability in People With Parkinson’s Disease

Background People with Parkinson’s disease (PD) are known to have motor learning difficulties. Although numerous studies have demonstrated that a single bout of aerobic exercise (AEX) can facilitate motor learning in non-disabled adults, the same beneficial effect in PD is unknown. Furthermore, associated neuroplastic changes have not been investigated. Objectives This study aimed to determine whether a single bout of aerobic exercise (AEX) can facilitate motor sequence learning in people with PD and to investigate the associated neurophysiological changes. Methods Thirty individuals with PD were recruited and randomized into the exercise group (PD + AEX) and non-exercise group (PD − AEX). At the first visit, corticomotor excitability was assessed using transcranial magnetic stimulation (TMS). All participants then performed a serial reaction time task (SRTT) followed by 20 minutes of moderately-high intensity aerobic exercise (AEX) for the PD + AEX group or rest for the PD − AEX group. The SRTT and TMS were reevaluated at 3 time points: immediately after aerobic exercise (AEX) or rest, on the second day after practice (D2), and a week after practice (D7). Results Both groups showed improvement throughout practice. At retention, the PD + AEX group showed improved SRTT performance on D7 compared to D2 (P = .001), while the PD − AEX group showed no change in performance. TMS results showed that the PD + AEX group had significantly higher corticomotor excitability than the PD − AEX group on D7. Conclusion A single session of aerobic exercise (AEX) could enhance motor sequence learning and induce neuroplastic changes. Clinicians can consider providing aerobic exercise (AEX) after motor task training for people with PD. Clinical registration: NCT04189887 (ClinicalTrials.gov).

The different effect of tongue motor task training (TTT) and strength training (ST) on the modulation of genioglossus corticomotor excitability and upper airway stability in rats.

The mechanical efficiency of upper airway (UA) muscles are pivotal in maintaining UA stability. We aimed to investigate if different tongue training approaches could differently induce signs of neuroplastic in the corticomotor pathways and upper airway stability changes. 36 Sprague-Dawley rats were trained daily for eight weeks to lick an isotonic force-sensing disc at targeting forces using 30%-50% of maximal achieved lick force (MALF) for tongue task training (TTT) or targeting force set above 50%, 60%, and 70% of MALF progressively for tongue strength training (TST). Corticomotor excitability was dynamically assessed by GG response to transcortical magnetic stimulation (TMS) at different sessions. GG EMG activity, GG ultrastructure and myosin heavy chain (MHC), UA dynamics were assessed after eight weeks. After 4 weeks, GG TMS latencies decreased in both tongue training groups when compared with the control group (p < .05) and this excitability was more stable in TTT group. After 8 weeks, both GG TMS response and EMG activity revealed increased excitability in TTT and TST groups. The apoptotic pathological morphology changes of GG ultrastructure were observed in TST group, but not TTT. Percentage of GG MHC type I fibers in TST group was higher than the control and TTT groups (p < .05). The UA Pcrit decreased significantly in TTT group (p < .05) and tend to decrease in TST group (p = .09). TTT could improve the UA stability and induce the neuroplastic changes more efficiently without training-induced muscle injury, while TST revealed a fatigue-resistance change in GG.

Motor training is improved by concurrent application of slow oscillating transcranial alternating current stimulation to motor cortex

Physical exercise and neurorehabilitation involve repetitive training that can induce changes in motor performance arising from neuroplasticity. Retention of these motor changes occurs via an encoding process, during which rapid neuroplastic changes occur in response to training. Previous studies show that transcranial alternating current stimulation (tACS), a form of non-invasive brain stimulation, can enhance encoding of a cognitive learning task during wakefulness. However, the effect of tACS on motor processes in the awake brain is unknown. In this study, forty-two healthy 18–35 year old participants received either 0.75 Hz (active) tACS (or sham stimulation) for 30 min during a ballistic thumb abduction motor training task. Training-related behavioural effects were quantified by assessing changes in thumb abduction acceleration, and neuroplastic changes were quantified by measuring motor evoked potential (MEP) amplitude of the abductor pollicis brevis muscle. These measures were reassessed immediately after the motor training task to quantify short-term changes, and then 24 h later to assess longer-term changes. Thumb abduction acceleration in both active and sham stimulation conditions increased immediately after the motor learning, consistent with effective training. Critically, participants in the active group maintained significantly higher thumb acceleration 24 h later (t40 = 2.810, P = 0.044). There were no significant changes or inter-group differences in MEPs for both conditions. The results suggest that 0.75 Hz tACS applied during motor training enhances the effectiveness of motor training, which manifests as enhancement in longer-term task benefits.

Impact of oral motor task training on corticomotor pathways and diadochokinetic rates in young healthy participants.

BackgroundStudies addressing the training‐induced neuroplasticity and interrelationships of the lip, masseter, and tongue motor representations in the human motor cortex using single syllable repetition are lacking.ObjectiveThis study investigated the impact of a repeated training in a novel PaTaKa diadochokinetic (DDK) orofacial motor task (OMT) on corticomotor control of the lips, masseter, and tongue muscles in young healthy participants.MethodsA total of 22 young healthy volunteers performed 3 consecutive days of training in an OMT. Transcranial magnetic stimulation was applied to elicit motor evoked potentials (MEPs) from the lip, masseter, tongue, and first dorsal interosseous (FDI, internal control) muscles. MEPs were assessed by stimulus–response curves and corticomotor mapping at baseline and after OMT. The DDK rate from PaTaKa single syllable repetition and numeric rating scale (NRS) scores were also obtained at baseline and immediately after each OMT. Repeated‐measures analysis of variance was used to detect differences at a significance level of 5%.ResultsThere was a significant effect of OMT and stimulus intensity on the lips, masseter, and tongue MEPs compared to baseline (p < .001), but not FDI MEPs (p > .05). OMT increased corticomotor topographic maps area (p < .001), and DDK rates (p < .01).ConclusionOur findings suggest that 3 consecutive days of a repeated PaTaKa training in an OMT can induce neuroplastic changes in the corticomotor pathways of orofacial muscles, and it may be related to mechanisms underlying the improvement of orofacial fine motor skills due to short‐term training. The clinical utility should now be investigated.

An Intelligent Motor Assessment Method Utilizing a Bi-Lateral Virtual-Reality Task for Stroke Rehabilitation on Upper Extremity.

Virtual reality (VR) has been widely adopted by therapists to provide rich motor training tasks. Time series data of motion trajectory accompanied with the interaction of VR system may contain important clues in regard to the assessment of motor function, however, clinical evaluation scales such as Fugl-Meyer Assessment (FMA), Wolf Motor Function Test (WMFT), and Test D'évaluation Des Membres Supérieurs Des Personnes Âgées (TEMPA) are highly depended in clinic. Further, there is not yet an assessment method that simultaneously consider motion trajectory and clinical evaluation scales. The objective of this study is to establish an evidence-based assessment model by machine-learning method that integrated motion trajectory of a VR task with clinical evaluation scales. In this study, a VR system for upper-limb motor training was proposed for stroke rehabilitation. Clinical trials with 20 stroke patients were performed. A variety of motor indicators that derived via motion trajectory were proposed. The correlations between motor indicators and clinical evaluation scales were examined. Further, motor indicators were integrated with evaluation scales to develop a machine-learning based model that represents an evidence-based motor assessment approach. Clinical evaluation scales, FMA, TEMPA and WMFT, were significantly progressed. A few motor indicators were found significantly correlated with clinical evaluation scales. The accuracy of machine-learning based assessment model was up to 86%. The proposed VR system is validated to be effective in motor rehabilitation. Motor indicators derived from motor trajectory were with potential for clinical motor assessment. Machine learning could be a promising tool to perform automatic assessment. Clinical and Translational Impact Statement-A VR task for motor rehabilitation was exanimated via clinical trials. Integrating motor indices with clinical assessment, a machine-learning model with accuracy of 86% was developed to evaluate motor function.

Effects of Dual-Task Training on Gait Parameters in Elderly Patients with Mild Dementia.

This study aimed to investigate the effectiveness of dual-task training (DTT) compared to single-task training (STT), on gait parameters in elderly patients with mild dementia (MD). Twenty-four elderly patients with MD were randomly assigned to the DTT (n = 13) or the STT group (n = 11). The DTT group performed a specific cognitive-motor DTT, while the STT group received only motor task training. Both training sessions lasted 8 weeks, with a frequency of 3 days per week, and the cognitive functions and gait parameters were measured. A statistically significant interaction effect was found between the two groups in stride length, stride velocity, cadence, step length, swing phase, stance phase, and double support phase (p < 0.05). After 8 weeks, the DTT group showed significant improvement in spatiotemporal parameters, except for the kinematic parameters (p < 0.05). In the between-group analysis, the DTT group showed more improvement than the STT group in stride velocity, step length, swing phase, stance phase, and double support (p < 0.05). These findings suggest that improvements in spatiotemporal gait parameters after DTT are reported in patients with MD. Our results can guide therapists to include dual tasks in their gait rehabilitation programs for the treatment of mild dementia.

Effect of dual tasking on a dynamic balance task in children with and without DCD.

The purpose of this study was to compare performance of children with Developmental Coordination Disorder (DCD) and typically developing (TD) children in a dual task paradigm with a dynamic balance task on the Wii Fit as primary task and a concurrent cognitive (counting) or a concurrent bimanual fine motor task as secondary tasks. Using a cross-sectional design, 25 children with DCD and 38 TD children were assessed with the Movement Assessment Battery for Children, 2nd edition (MABC-2) and Divided Attention (DA) task of the KiTAP. Next, the single- and dual-tasks were performed and the level of interference or facilitation of the dual tasks was calculated. Regression analysis determined the predictive value of the DA and MABC-2 component balance outcomes on the dual task performance. On the motor and attentional tasks, the group of children with DCD scored significantly below the level of the TD children. The dual task effect showed similar interference and facilitation of tasks in the different dual-task conditions in both groups. In the dual task-cognitive condition, the divided attention abilities and the MABC-2 balance score predicted 25% of the Wii Fit dynamic balance task performance, whereas in the dual task-motor condition this was higher (31.6%). In both conditions, DA was a stronger predictor than MABC balance score and appears to be an important factor to consider when developing motor task training for children with DCD.

Congruency of Information Rather Than Body Ownership Enhances Motor Performance in Highly Embodied Virtual Reality.

In immersive virtual reality, the own body is often visually represented by an avatar. This may induce a feeling of body ownership over the virtual limbs. Importantly, body ownership and the motor system share neural correlates. Yet, evidence on the functionality of this neuroanatomical coupling is still inconclusive. Findings from previous studies may be confounded by the congruent vs. incongruent multisensory stimulation used to modulate body ownership. This study aimed to investigate the effect of body ownership and congruency of information on motor performance in immersive virtual reality. We aimed to modulate body ownership by providing congruent vs. incongruent visuo-tactile stimulation (i.e., participants felt a brush stroking their real fingers while seeing a virtual brush stroking the same vs. different virtual fingers). To control for congruency effects, unimodal stimulation conditions (i.e., only visual or tactile) with hypothesized low body ownership were included. Fifty healthy participants performed a decision-making (pressing a button as fast as possible) and a motor task (following a defined path). Body ownership was assessed subjectively with established questionnaires and objectively with galvanic skin response (GSR) when exposed to a virtual threat. Our results suggest that congruency of information may decrease reaction times and completion time of motor tasks in immersive virtual reality. Moreover, subjective body ownership is associated with faster reaction times, whereas its benefit on motor task performance needs further investigation. Therefore, it might be beneficial to provide congruent information in immersive virtual environments, especially during the training of motor tasks, e.g., in neurorehabilitation interventions.

Reversed Polarity bi-tDCS over M1 during a Five Days Motor Task Training Did Not Influence Motor Learning. A Triple-Blind Clinical Trial.

Transcranial direct current stimulation (tDCS) has been investigated as a way of improving motor learning. Our purpose was to explore the reversal bilateral tDCS effects on manual dexterity training, during five days, with the retention component measured after 5 days to determine whether somatosensory effects were produced. In this randomized, triple-blind clinical trial, 28 healthy subjects (14 women) were recruited and randomized into tDCS and placebo groups, although only 23 participants (13 women) finished the complete protocol. Participants received the real or placebo treatment during five consecutive days, while performing a motor dexterity training program of 20 min. The motor dexterity and the sensitivity of the hand were assessed pre- and post-day 1, post 5 days of training, and 5 days after training concluded. Training improved motor dexterity, but tDCS only produced a tendency to improve retention. The intervention did not produce changes in the somatosensory variables assessed. Thus, reversal bi-tDCS had no effects during motor learning on healthy subjects, but it could favor the retention of the motor skills acquired. These results do not support the cooperative inter-hemispheric model.

An Evidence-Based Intelligent Method for Upper-Limb Motor Assessment via a VR Training System on Stroke Rehabilitation

Recently, virtual-reality (VR) has been an emerging technology, to this regard, it is widely employed by therapists to provide rich training tasks for the purpose of motor rehabilitation in clinics. Meanwhile, along with the progress of sensing technologies as means for the interaction with virtual environment, a large amount of data, such as motor trajectory, foot pressure or electromyography, is measured via VR-based motor training tasks and is considered as important clues for functional evaluations. However, very few study thoroughly applied the sensor-based data for motor assessment, instead, evaluation scales, such as TEMPA or Fugl-Meyer, were highly relied. In this study, a VR upper-limb motor training system was proposed for stroke rehabilitation. Clinical trials with 22 stroke patients were performed to exanimate the effectiveness of the propose VR system. Moreover, a variety of motor indicators derived via motion trajectory were proposed. Further, integrating multi-model data, such as motion trajectory, task performance and evaluation scales, machine-learning method was applied to develop evidence-based assessment models in order to evaluate upper-limb motor function. The results indicated that the proposed VR system was significantly effective for motor rehabilitation. Also, a few motor indicators were found significantly different between pre and post trials and were highly correlated with the evaluation scales. Finally, with the fusion of multi-model data, the accuracy rate of machine-learning assessment model was up to 92.72% which revealed its great potential for clinical use.

Aspects of cortical area responsibilities while learning a visually cued spatiotemporal motor task.

Aspects of cortical area responsibilities while learning a visually cued spatiotemporal motor task.

Effect of Dual Task Training on Balance and Functional Mobility in Children with Cerebral Palsy

Research background. It was found that dual task training improves functional abilities in subjects with neurological disorders, however it is not known how dual task training affects balance and functional mobility in children with cerebral palsy (CP).The aim. To determine the effectiveness of dual motor tasks training and basic physiotherapy programme on balance and functional mobility in children with spastic diplegic CP.Methods. The study included 20 children with spastic diplegic CP. Subjects were randomly assigned into two groups: control group (40 min basic physiotherapy programme) and experimental group (20 min basic physiotherapy programme and 20 min dual motor task training). Physiotherapy was applied for 3 weeks (5 times a week). Balance and functional mobility were assessed at baseline and at the end.Results. There was a statistically significant improvement in balance and functional mobility in both the control and experimental groups after three weeks of physiotherapy (p &lt; 0.05). Comparing two groups with each other, there was a statistically significant improvement in the experimental group on balance and walking (p &lt; 0.05).Conclusion. Dual task training can be used as an effective intervention to improve balance and walking in children with spastic diplegic CP.Keywords: motor tasks, cerebral palsy, balance, functional mobility.

Proximal Upper Limb Sensorimotor Integration in Response to Novel Motor Skill Acquisition.

Previous studies have shown significant changes in cortical and subcortical evoked potential activity levels in response to motor training with the distal upper-limb muscles. However, no studies to date have assessed the neurological processing changes in somatosensory evoked potentials (SEPs) associated with motor training whole-arm movements utilizing proximal upper-limb muscles. The proximal upper-limb muscles are a common source of work-related injuries, due to repetitive glenohumeral movements. Measuring neurophysiological changes following performance of a proximal motor task provide insight into potential neurophysiological changes associated with occupational postures and movements involving proximal upper limb muscles. This study sought to assess the impact of a novel motor skill acquisition task on neural processing of the proximal upper-limb muscle groups, through the measurement of short-latency median nerve SEPs. One group of 12 participants completed a novel motor training task, consisting of tracing a sinusoidal waveform varying in amplitude and frequency. Baseline SEP measurements were recorded from each participant, followed by a mental recitation control task. Pre-test SEP measurements were then recorded, followed by the motor training task, and post-test SEP recordings. The participants completed the tracing with their right thumb, using glenohumeral rotation only to move their hand. Significant improvements in task accuracy were demonstrated, indicating that motor acquisition had occurred. Significant changes were also seen in the N11, N13, N20, N24, P25, and the N30 SEP peaks were seen following the motor training task. Conclusion: Early SEPs appear to be a sensitive measure of changes in sensorimotor integration in response to novel motor skill acquisition within the proximal upper-limb muscles.

Corticomotor reorganization during short-term visuomotor training in the lower back: A randomized controlled study.

IntroductionAccumulating evidence suggests that motor skill training is associated with structural and functional reorganization of the primary motor cortex. However, previous studies have focussed primarily upon the upper limb, and it is unclear whether comparable reorganization occurs following training of other regions, such as the lower back. Although this holds important implications for rehabilitation, no studies have examined corticomotor adaptations following short‐term motor training in the lower back.MethodThe aims of this study were to (a) determine whether a short‐term lumbopelvic tilt visuomotor task induced reorganization of the corticomotor representations of lower back muscles, (b) quantify the variability of corticomotor responses to motor training, and (c) determine whether any improvements in task performance were correlated with corticomotor reorganization. Participants were allocated randomly to perform a lumbopelvic tilt motor training task (n = 15) or a finger abduction control task involving no lumbopelvic movement (n = 15). Transcranial magnetic stimulation was used to map corticomotor representations of the lumbar erector spinae before, during, and after repeated performance of the allocated task.ResultsNo relationship between corticomotor reorganization and improved task performance was identified. Substantial variability was observed in terms of corticomotor responses to motor training, with approximately 50% of participants showing no corticomotor reorganization despite significant improvements in task performance.ConclusionThese findings suggest that short‐term improvements in lower back visuomotor task performance may be driven by changes in remote subcortical and/or spinal networks rather than adaptations in corticomotor pathways. However, further research using tasks of varying complexities and durations is required to confirm this hypothesis.

Constraint-Induced Movement Therapy for Lower Extremity Function: Describing the LE-CIMT Protocol.

Constraint-induced movement therapy (CIMT) is comprised of a set of techniques shown to produce significant changes in upper extremity (UE) function following stroke and other disorders. The significant positive results obtained with the UE protocol have led to the development of LE-CIMT, an intervention to improve lower extremity (LE) function. However, some modifications of the UE protocol were needed, including omitting use of a restraint device, development of supervised motor training tasks to emphasize movement of the lower limb, and adaptation of the UE Motor Activity Log for the lower extremity. The LE-CIMT protocol includes: (1) intensive supervised training delivered for 3.5h/d for 10 consecutive weekdays, (2) use of shaping as a strategy for motor training, (3) application of a transfer package, and (4) strongly encouraging use of the more-affected LE with improved coordination. The transfer package consists of several strategies to facilitate transfer of the improved motor skills developed during supervised treatment to everyday situations. Research to date has yielded positive results. However, the intervention protocol continues to evolve. The purpose of this article is to describe the components of the complete LE-CIMT protocol to promote further development and investigation of this approach.

A Novel Robot-Aided Upper Limb Rehabilitation Training System Based on Multimodal Feedback

During robot-aided rehabilitation exercises, monotonous, and repetitive actions can, to the subject, feel tedious and tiring, so improving the subject's motivation and active participation in the training is very important. A novel robot-aided upper limb rehabilitation training system, based on multimodal feedback, is proposed in this investigation. To increase the subject's interest and participation, a friendly graphical user interface and diversiform game-based rehabilitation training tasks incorporating multimodal feedback are designed, to provide the subject with colorful and engaging motor training. During this training, appropriate visual, auditory, and tactile feedback is employed to improve the subject's motivation via multi-sensory incentives relevant to the training performance. This approach is similar to methods applied by physiotherapists to keep the subject focused on motor training tasks. The experimental results verify the effectiveness of the designed multimodal feedback strategy in promoting the subject's participation and motivation.

Motor Task-Dependent Dissociated Effects of Transcranial Random Noise Stimulation in a Finger-Tapping Task Versus a Go/No-Go Task on Corticospinal Excitability and Task Performance.

Background and Objective: Transcranial random noise stimulation (tRNS) is an emerging non-invasive brain stimulation technique to modulate brain function, with previous studies highlighting its considerable benefits in therapeutic stimulation of the motor system. However, high variability of results and bidirectional task-dependent effects limit more widespread clinical application. Task dependency largely results from a lack of understanding of the interaction between externally applied tRNS and the endogenous state of neural activity during stimulation. Hence, the aim of this study was to investigate the task dependency of tRNS-induced neuromodulation in the motor system using a finger-tapping task (FT) versus a go/no-go task (GNG). We hypothesized that the tasks would modulate tRNS’ effects on corticospinal excitability (CSE) and task performance in opposite directions.Methods: Thirty healthy subjects received 10 min of tRNS of the dominant primary motor cortex in a double-blind, sham-controlled study design. tRNS was applied during two well-established tasks tied to diverging brain states. Accordingly, participants were randomly assigned to two equally-sized groups: the first group performed a simple motor training task (FT task), known primarily to increase CSE, while the second group performed an inhibitory control task (go/no-go task) associated with inhibition of CSE. To establish task-dependent effects of tRNS, CSE was evaluated prior to- and after stimulation with navigated transcranial magnetic stimulation.Results: In an ‘activating’ motor task, tRNS during FT significantly facilitated CSE. FT task performance improvements, shown by training-related reductions in intertap intervals and increased number of finger taps, were similar for both tRNS and sham stimulation. In an ‘inhibitory’ motor task, tRNS during GNG left CSE unchanged while inhibitory control was enhanced as shown by slowed reaction times and enhanced task accuracy during and after stimulation.Conclusion: We provide evidence that tRNS-induced neuromodulatory effects are task-dependent and that resulting enhancements are specific to the underlying task-dependent brain state. While mechanisms underlying this effect require further investigation, these findings highlight the potential of tRNS in enhancing task-dependent brain states to modulate human behavior.

0069 The Different Effect of Tongue Motor Task Training (TTT) and Strength Training (ST) on the Modulation of Genioglossus Corticomotor Excitability in Rats

The neuromuscular activation of upper airway stabilizing muscles, their propensity to fatigue and mechanical efficiency are pivotal in maintaining UA stability. Since training rats in a skilled reaching condition will induce task-related changes in the associated motor cortex, we aimed to investigate if different tongue training paradigms using fixed-training-intensity could differently induce neuroplastic changes in the corticomotor pathways, and to detect the time course of such changes. 18 water-restricted adult male Sprague-Dawley rats were trained to lick an isometric force-sensing disc at targeting forces for water reinforcement with sound feedback. In TTT group, 30–50% of maximal protrusion force (MPF) was used as a target window, while the ST paradigm used a progressive resistance training program with targeting force set above 50%, 60% and 70% of MPF, progressively. The rats in two groups were trained daily for two month with the same training intensity (1000 g·s per day). Corticomotor excitability was assessed via motor evoked potentials (MEPs) in genioglossus evoked by transcranial magnetic stimulation (TMS) at four sessions: at baseline before training, at different times after the 4th and 8th weeks of training. Overall, after 4 weeks in both groups, MEPs latencies of genioglossus evoked by TMS decreased immediately after training and dropped to the nadir 20 minutes after training compared to baseline (3.5 ± 0.5 ms vs. 4.8 ± 0.2 ms). This decreased latency lasted up to 80 minutes in TTT-treated rats; but in ST group, it rebound above the baseline value after 20 minutes and reached apex at 80 minutes (5.3 ± 0.4 ms). After 8 weeks in both groups, MEPs latencies consistently decreased within the 2 hours after training, and the precision of task performance (percent of peak force inside target window) significantly increased in TTT-treated rats. Tongue-task-training is associated with stable increment of genioglossus corticomotor excitability in a shorter time of training, while the tongue-strength-training rats might suffer fatigue at early stages of training. supported by the 2016 China National Nature Fund, number 81670085.

0068 Effect of Tongue Motor Task Training on Serotonergic Excitatory Drive to Genioglossus Electromyographic Activity in Rats

0068 Effect of Tongue Motor Task Training on Serotonergic Excitatory Drive to Genioglossus Electromyographic Activity in Rats