Rehabilitation of the afasic patient in speech therapy

Aphasias are considered to be neurological linguistic disorders in which the comprehension and/or expression of oral and/or written language is compromised, thus having a significant potential impact on the quality of life of an individual and his / her family. Although much studied in its neurophysiological mechanism, aphasia is not always discussed in terms of rehabilitation. Therefore, this article aims to discuss the scientific production in speech therapy on the rehabilitation of aphasia. For this purpose, an Integrative Review of Literature was carried out, covering the period from 2000 to 2021 on the Scielo and BVS data platforms of articles available in full and in the Portuguese language, using as a descriptor the unitermo "aphasia", in which the articles found were submitted to the relevance tests I and II, in which the final sample made only those that passed the established criteria. A total of 236 articles were found on the Scielo platform, with only 29 discussing rehabilitation and only 5 on speech therapy. In the BVS platform, 98.901 articles were found, but only 86 were discussing deaf aphasia and were available, none of which addressed speech therapy rehabilitation. The electronic search reached a total of 5 relevant articles that included the theme of speech and hearing rehabilitation to the aphasic patient, all of them being from the Scielo platform. Thus, scientific scarcity on the subject of aphasia becomes evident, and it is necessary to invest in production that encapsulate the therapeutic behavior of the speech-language pathologist. As afasias são consideradas distúrbios linguísticos de cunho neurológico em que a compreensão e/ou expressão da linguagem oral e/ou escrita encontra-se comprometida, tendo desta maneira um potencial significativo de impacto na qualidade de vida de um indivíduo e sua família. Embora muito estudada em seu mecanismo neurofisiológico, as afasias nem sempre são discutidas sob o aspecto de reabilitação. Diante disso, este artigo objetiva discutir sobre a produção cientifica em fonoaudiologia sobre a reabilitação da afasia. Para tanto, foi realizada uma Revisão Integrativa da Literatura, contemplando o período de 2000 a 2021 nas plataformas de dados Scielo e BVS de artigos disponíveis na íntegra e no idioma em português, utilizando como descritor o unitermo “afasia”, em que os artigos encontrados foram submetidos aos testes de relevância I e II, em que fizeram a amostra final apenas aqueles que passaram pelos critérios estabelecidos. Foram encontrados na plataforma Scielo o total de 236 artigos, sendo que apenas 29 discutiam sobre reabilitação e apenas 5 sobre terapia fonoaudiológica. Na plataforma BVS foram encontrados 98.901 artigos, porém apenas 86 discutiam sobre afasia de fato e estavam disponíveis, sendo que nenhum abordava a reabilitação fonoaudiológica. A busca eletrônica alcançou o total de 5 artigos relevantes que contemplassem a temática de reabilitação fonoaudiológica ao paciente afásico, sendo todos da plataforma Scielo. Assim, torna-se evidente a escassez científica sobre o tema de afasia, sendo necessário investimentos para produção que embase a conduta terapêutica do profissional fonoaudiólogo.

Combining Action Observation Treatment with a Brain–Computer Interface System: Perspectives on Neurorehabilitation

Action observation treatment (AOT) exploits a neurophysiological mechanism, matching an observed action on the neural substrates where that action is motorically represented. This mechanism is also known as mirror mechanism. In a typical AOT session, one can distinguish an observation phase and an execution phase. During the observation phase, the patient observes a daily action and soon after, during the execution phase, he/she is asked to perform the observed action at the best of his/her ability. Indeed, the execution phase may sometimes be difficult for those patients where motor impairment is severe. Although, in the current practice, the physiotherapist does not intervene on the quality of the execution phase, here, we propose a stimulation system based on neurophysiological parameters. This perspective article focuses on the possibility to combine AOT with a brain–computer interface system (BCI) that stimulates upper limb muscles, thus facilitating the execution of actions during a rehabilitation session. Combining a rehabilitation tool that is well-grounded in neurophysiology with a stimulation system, such as the one proposed, may improve the efficacy of AOT in the treatment of severe neurological patients, including stroke patients, Parkinson’s disease patients, and children with cerebral palsy.

A Novel Approach to Assessment of Perceptual-Motor Efficiency and Training-Induced Improvement in the Performance Capabilities of Elite Athletes

Standard clinical assessments of mild traumatic brain injury are inadequate to detect subtle abnormalities that can be revealed by sophisticated diagnostic technology. An association has been observed between sport-related concussion (SRC) and subsequent musculoskeletal injury, but the underlying neurophysiological mechanism is not currently understood. A cohort of 16 elite athletes (10 male, 6 female), which included nine individuals who reported a history of SRC (5 male, 4 female) that occurred between 4 months and 8 years earlier, volunteered to participate in a 12-session program for assessment and training of perceptual-motor efficiency. Performance metrics derived from single- and dual-task whole-body lateral and diagonal reactive movements to virtual reality targets in left and right directions were analyzed separately and combined in various ways to create composite representations of global function. Intra-individual variability across performance domains demonstrated very good SRC history classification accuracy for the earliest 3-session phase of the program (Reaction Time Dispersion AUC = 0.841; Deceleration Dispersion AUC = 0.810; Reaction Time Discrepancy AUC = 0.825, Deceleration Discrepancy AUC = 0.794). Good earliest phase discrimination was also found for Composite Asymmetry between left and right movement directions (AUC = 0.778) and Excursion Average distance beyond the minimal body displacement necessary for virtual target deactivation (AUC = 0.730). Sensitivity derived from Youden's Index for the 6 global factors ranged from 67 to 89% and an identical specificity value of 86% for all of them. Median values demonstrated substantial improvement from the first 3-session phase to the last 3-session phase for Composite Asymmetry and Excursion Average. The results suggest that a Composite Asymmetry value ≥ 0.15 and an Excursion Average value ≥ 7 m, provide reasonable qualitative approximations for clinical identification of suboptimal perceptual-motor performance. Despite acknowledged study limitations, the findings support a hypothesized relationship between whole-body reactive agility performance and functional connectivity among brain networks subserving sensory perception, cognitive decision-making, and motor execution. A complex systems approach appears to perform better than traditional data analysis methods for detection of subtle perceptual-motor impairment, which has the potential to advance both clinical management of SRC and training for performance enhancement.

Computational annealing as mechanism in eye movement desensitization and reprocessing (EMDR)

The computational annealing model offers a plausible neurophysiological mechanism to account for eye movement desensitization and reprocessing’s (EMDR) psychotherapeutic effectiveness. The model is informed by analogy to the physical annealing of metals and the related computational method of simulated annealing. It proposes that observed instances of chaotic activity and criticality within the nervous system serve to loosen constraints within memory networks, allowing them to reorganize in a direction of optimal internal coherence and harmony. The role of eye movements is to generate corollary discharge within relevant brain areas, inducing transient increases in criticality within working memory; effectively raising the computational temperature and facilitating informational and energetic flow towards optimal resolution of trauma related memories. Raising the computational temperature overcomes constraints maintaining fragmented and discordant cognitive schemas, enabling fuller integration with the broader sense of self. Computational annealing provides an outline of a conceptual bridge between observations made at the microscopic neurophysiological level, and those made at the macroscopic, behavioral level of description.

Relative Power Correlates With the Decoding Performance of Motor Imagery Both Across Time and Subjects

One of the most significant challenges in the application of brain-computer interfaces (BCI) is the large performance variation, which often occurs over time or across users. Recent evidence suggests that the physiological states may explain this performance variation in BCI, however, the underlying neurophysiological mechanism is unclear. In this study, we conducted a seven-session motor-imagery (MI) experiment on 20 healthy subjects to investigate the neurophysiological mechanism on the performance variation. The classification accuracy was calculated offline by common spatial pattern (CSP) and support vector machine (SVM) algorithms to measure the MI performance of each subject and session. Relative Power (RP) values from different rhythms and task stages were used to reflect the physiological states and their correlation with the BCI performance was investigated. Results showed that the alpha band RP from the supplementary motor area (SMA) within a few seconds before MI was positively correlated with performance. Besides, the changes of RP between task and pre-task stage from theta, alpha, and gamma band were also found to be correlated with performance both across time and subjects. These findings reveal a neurophysiological manifestation of the performance variations, and would further provide a way to improve the BCI performance.

High-gain observer-based nonlinear control scheme for biomechanical sit to stand movement in the presence of sensory feedback delays

Sit-to-stand movement (STS) is a mundane activity, controlled by the central-nervous-system (CNS) via a complex neurophysiological mechanism that involves coordination of limbs for successful execution. Detailed analysis and accurate simulations of STS task have significant importance in clinical intervention, rehabilitation process, and better design for assistive devices. The CNS controls STS motion by taking inputs from proprioceptors. These input signals suffer delay in transmission to CNS making movement control and coordination more complex which may lead to larger body exertion or instability. This paper deals with the problem of STS movement execution in the presence of proprioceptive feedback delays in joint position and velocity. We present a high-gain observer (HGO) based feedback linearization control technique to mimic the CNS in controlling the STS transfer. The HGO estimates immeasurable delayed states to generate input signals for feedback. The feedback linearization output control law generates the passive torques at joints to execute the STS movement. The H2 dynamic controller calculates the optimal linear gains by using physiological variables. The whole scheme is simulated in MATLAB/Simulink. The simulations illustrate physiologically improved results. The ankle, knee, and hip joint position profiles show a high correlation of 0.91, 0.97, 0.80 with the experimentally generated reference profiles. The faster observer dynamics and global boundness of controller result in compensation of delays. The low error and high correlation of simulation results demonstrate (1) the reliability and effectiveness of the proposed scheme for customization of human models and (2) highlight the fact that for detailed analysis and accurate simulations of STS movement the modeling scheme must consider nonlinearities of the system.

Salicylate-Induced Changes in Hearing Thresholds in Mongolian Gerbils Are Correlated With Tinnitus Frequency but Not With Tinnitus Strength

Tinnitus is an auditory phantom percept without external sound sources. Despite the high prevalence and tinnitus-associated distress of affected patients, the pathophysiology of tinnitus remains largely unknown, making prevention and treatments difficult to develop. In order to elucidate the pathophysiology of tinnitus, animal models are used where tinnitus is induced either permanently by noise trauma or transiently by the application of salicylate. In a model of trauma-induced tinnitus, we have suggested a central origin of tinnitus-related development of neuronal hyperactivity based on stochastic resonance (SR). SR refers to the physiological phenomenon that weak subthreshold signals for given sensors (or synapses) can still be detected and transmitted if appropriate noise is added to the input of the sensor. The main objective of this study was to characterize the neurophysiological and behavioral effects during salicylate-induced tinnitus and compare these to the conditions within the trauma model. Our data show, in line with the pharmacokinetics, that hearing thresholds generally increase 2 h after salicylate injections. This increase was significantly stronger within the region of best hearing compared to other frequencies. Furthermore, animals showed behavioral signs of tinnitus during that time window and frequency range as assessed by gap prepulse inhibition of the acoustic startle reflex (GPIAS). In contrast to animals with noise trauma-induced tinnitus, salicylate-induced tinnitus animals showed no correlation between hearing thresholds and behavioral signs of tinnitus, indicating that the development of tinnitus after salicylate injection is not based on SR as proposed for the trauma model. In other words, salicylate-induced tinnitus and noise trauma-induced tinnitus are not based on the same neurophysiological mechanism.