Motor Imagery Practice and Increased Tongue Strength: A Case Series Feasibility Report

Characterization and classification of kinesthetic motor imagery levels

Objective.Kinesthetic Motor Imagery (KMI) represents a robust brain paradigm intended for electroencephalography (EEG)-based commands in brain-computer interfaces (BCIs). However, ensuring high accuracy in multi-command execution remains challenging, with data from C3 and C4 electrodes reaching up to 92% accuracy. This paper aims to characterize and classify EEG-based KMI of multilevel muscle contraction without relying on primary motor cortex signals.Approach.A new method based on Hurst exponents is introduced to characterize EEG signals of multilevel KMI of muscle contraction from electrodes placed on the premotor, dorsolateral prefrontal, and inferior parietal cortices. EEG signals were recorded during a hand-grip task at four levels of muscle contraction (0%, 10%, 40%, and 70% of the maximal isometric voluntary contraction). The task was executed under two conditions: first, physically, to train subjects in achieving muscle contraction at each level, followed by mental imagery under the KMI paradigm for each contraction level. EMG signals were recorded in both conditions to correlate muscle contraction execution, whether correct or null accurately. Independent component analysis (ICA) maps EEG signals from the sensor to the source space for preprocessing. For characterization, three algorithms based on Hurst exponents were used: the original (HO), using partitions (HRS), and applying semivariogram (HV). Finally, seven classifiers were used: Bayes network (BN), naive Bayes (NB), support vector machine (SVM), random forest (RF), random tree (RT), multilayer perceptron (MP), and k-nearest neighbors (kNN).Main results.A combination of the three Hurst characterization algorithms produced the highest average accuracy of 96.42% from kNN, followed by MP (92.85%), SVM (92.85%), NB (91.07%), RF (91.07%), BN (91.07%), and RT (80.35%). of 96.42% for kNN.Significance.Results show the feasibility of KMI multilevel muscle contraction detection and, thus, the viability of non-binary EEG-based BCI applications without using signals from the motor cortex.

Identifying Non-Traditional Approaches to Swallowing Rehabilitation: A Scoping Review

In recent years, dysphagia care has shifted toward a more patient-centered approach. This means that dysphagia clinicians are considering more factors in the treatment process including the goals of care, quality of life, and cultural values. The purpose of this scoping review was to examine relevant research and identify dysphagia interventions outside of those traditionally used by dysphagia clinicians that may improve swallowing function. A review of relevant studies was conducted using search terms related to swallowing and treatment. The search yielded 8439 unique studies. Of the 283 articles that underwent a full-text review, 37 articles were included in the final review. These articles highlighted three potential areas of non-traditional dysphagia intervention that may serve to provide holistic care, while also aiming to improve swallowing mechanisms: acupuncture and Eastern medicine interventions, vocal exercises, and physical function exercises. The results suggest that dysphagia clinicians should work collaboratively with other allied health professionals and consider non-traditional approaches to dysphagia care. Through the identification of potentially effective but non-traditional or non-Eurocentric interventions for dysphagia care, clinicians may promote a culturally relevant, patient-centered approach, in turn increasing patient acceptance of treatment plans and compliance. Future research should explore the efficacy and feasibility of these interventions in dysphagia rehabilitation, as well as their effectiveness compared to more traditional approaches.

Expanding Rehabilitation Options for Dysphagia: Skill-Based Swallowing Training

Over the past four decades, our understanding of swallowing neural control has expanded dramatically. However, until recently, advances in rehabilitation approaches for dysphagia have not kept pace, with a persistent focussing on strengthening peripheral muscle. This approach is no doubt very appropriate for some if not many of our patients. But what if the dysphagia is not due to muscles weakness? The purpose of this clinical manuscript is to reflect on where we have been, where we are now and perhaps where we need to go in terms of our understanding of swallowing motor control and rehabilitation of motor control impairments. This compilation is presented to clinicians in the hope that suggesting approaches "outside the box" will inspire clinicians to focus their attention "inside the box" to ultimately improve rehabilitation and long-term outcomes for patients with dysphagia.

Assessment of Motor Cortex in Active, Passive and Imagery Wrist Movement Using Functional MRI

Background:

Functional Magnetic resonance imaging (fMRI) measures the small fluctuation of blood flow happening during task-fMRI in brain regions.

Objective:

This research investigated these active, imagery and passive movements in volunteers design to permit a comparison of their capabilities in activating the brain areas.

Material and Methods:

In this applied research, the activity of the motor cortex during the right-wrist movement was evaluated in 10 normal volunteers under active, passive, and imagery conditions. T2* weighted, three-dimensional functional images were acquired using a BOLD sensitive gradient-echo EPI (echo planar imaging) sequence with echo time (TE) of 30 ms and repetition time (TR) of 2000 ms. The functional data, which included 248 volumes per subject and condition, were acquired using the blocked design paradigm. The images were analyzed by the SPM12 toolbox, MATLAB software.

Results:

The findings determined a significant increase in signal intensity of the motor cortex while performing the test compared to the rest time (p< 0.05). It was also observed that the active areas in hand representation of the motor cortex are different in terms of locations and the number of voxels in different wrist directions. Moreover, the findings showed that the position of active centers in the brain is different in active, passive, and imagery conditions.

Conclusion:

Results confirm that primary motor cortex neurons play an essential role in the processing of complex information and are designed to control the direction of movement. It seems that the findings of this study can be applied for rehabilitation studies.

Effects of a Multifaceted Intervention Program on the Eating Ability of Nursing Home Residents

Oropharyngeal dysphagia is a common problem for nursing home residents that leads to aspiration pneumonia and malnutrition. Musculature surrounding head and neck and tongue strength are crucial for safe and efficient oropharyngeal swallowing. Oral hygiene facilitates the smooth swallowing. The aim of this study was thus to investigate the effects of a multifaceted intervention program which combines the interactive oral activities, tongue strength training and oral cleaning procedure on the eating ability of nursing home residents. A sequential, multiple time series, single-group quasi-experimental research design was used, and 41 residents were recruited to participate in this study. The study was divided into three phases, each lasting two months. In phase 1, the participants were conducting their usual activities, except that the outcome variables were measured on five occasions to obtain baseline data. Phase 2 was a two-month washout period, and phase 3 was the intervention period. Thirty-six residents completed phase 1, and 34 residents completed the phase 3 intervention period. The eight-week phase 3 intervention program comprised three sessions per day, conducted seven days a week, with each session lasting 15–20 min. Outcome variables were measured at weeks 0, 2, 4, 6, and 8 in phases 1 and 3 to evaluate the feasibility of the program. Following the intervention program, controlling for baseline differences, the patients’ tongue strength, food consumption, mealtime duration, oral health, and dysphagia severity were significantly improved in phase 3 relative to phase 1. These improvements lasted through to at least 2 months posttest. The study illustrates that this multifaceted intervention program may be an effective approach for improving the eating ability of nursing home residents.

A Randomized Controlled Trial Comparing Physical and Mental Lingual Exercise for Healthy Older Adults

Mental practice using motor imagery (MP-MI) has been shown to improve motor outcomes of upper and lower extremities especially when combined with physical exercise. Here, we studied community-dwelling, healthy older adults to determine the effects of including an MP-MI component with lingual strengthening exercise. In this pilot study, twenty-nine typically aging participants were assigned to an intervention group: physical lingual exercise (n = 7), physical and MP-MI lingual exercise (n = 8), MPMI lingual exercise (n = 7), or a control group (placebo exercise) (n = 7). All participants completed the assigned exercise regimen with three sessions per day, three days a week, for 6 consecutive weeks. Maximum isometric pressure (MIP) and regular effort saliva swallowing (RESS) pressure were collected at baseline and weeks 2, 4, and 6. A post hoc Bonferroni corrected treatment effect from baseline to week 6 was shown for only participants in the MP-MI/Physical exercise group for MIP (p = 0.003 MPMI/ Physical group; p = 0.11 Control group; p = 0.32 Physical only group; p = 0.14 MP-MI only group) and RESS (p = 0.009 MP-MI/Physical group; p = 0.14 Control group; p = 0.10 Physical only group; p = 0.04 MP-MI only group). Findings also indicate spontaneous carryover of significantly increased swallowing pressure when mental and physical exercise are combined. In conclusion, the potential effect of including an MPMI lingual exercise component in preventative and rehabilitative frameworks with older persons to possibly enhance functional swallowing improvement is promising and should be investigated.

Mental Practice Using Motor Imagery in Dysphagia Rehabilitation: A Survey of Practicing Speech-Language Pathologists

Mental practice (MP) using motor imagery is recognized as an effective clinical tool in rehabilitative medicine for improving motor performance. Preliminary data using MP in dysphagia rehabilitation are promising, though nothing is known about the current landscape among speech-language pathologists (SLPs) relating to MP implementation. This nationwide study surveys practicing SLPs about knowledge and practice patterns of using MP to gain a better understanding of the current knowledge, as well as perceived benefits and challenges in using MP. Descriptive data are reported and open-ended questions analyzed for emerging themes using inductive coding. Over half of the participants were familiar or somewhat familiar with motor imagery in the context of dysphagia rehabilitation, though only 16% of those SLPs reported using MP with a patient. Nearly 75% of respondents expressed interest in learning more about MP. Emerging themes include factors SLPs perceive to limit patient engagement, evidence-based practice concerns, and therapeutic environmental factors. More research on MP and access to training for clinicians is needed in the area of dysphagia rehabilitation to address acknowledged interest in MP.

Effects of mental and physical orofacial training on pressure pain sensitivity and tongue strength: A single-blind randomized controlled trial

OBJECTIVES

The main objective of this study was to analyze differences on pain pressure thresholds, tongue strength and perceived effort between various orofacial motor exercise training dosages of mental representation training through motor imagery (MI) and action observation (AO), first in isolation and then in combination with real exercise performance.

METHODS

A single-blind randomized controlled trial was designed. 48 asymptomatic individuals were randomized into two groups: Intensive training group (IG) and Moderate training group (MG). Both groups performed a first session of MI and AO of orofacial exercises training and a second session of actual orofacial exercises combined with mental representation training, but with different dosage in terms of series and repetitions. Pain pressure thresholds (PPTs) in the masseter and temporal muscles and tongue muscle strength were the main variables.

RESULTS

Regarding the PPT, ANOVA revealed significant between-group differences, where MG showed a significantly higher PPT than IG at post-day2, with a medium effect size. Both groups showed with-in group differences between pre and post intervention measures in the first session, but only the IG showed differences in the second. Regarding tongue muscle strength, ANOVA revealed significant within-group differences only in MG between the pre-day and post-day first intervention.

CONCLUSION

The results of the present study suggest that movement representation training performed in isolation may have a positive effect on PPTs and tongue muscle strength. In addition, the combination with the actual execution of the exercises could be considered effective, but it is necessary to take into account the training dosage to avoid fatigue responses.