Upper Limb Electromyographic Responses to Motor Imagery and Action Observation in Acquired Brain Injury.

Acquired Brain Injuries are one of the leading causes of mortality and disability worldwide. One of the most frequent sequelae is motor impairment of the upper limbs, which affects people's functionality and quality of life. Following the discovery of mirror neurons, new techniques were developed based on the mechanisms of neuronal plasticity, such as motor imagery (MI) and action observation (AO). We propose a protocol using electromyographic recordings of forearm muscles in people who have suffered a stroke during an MI task and an AO task. Three different experimental conditions will be studied during the electromyographic recordings: control recording, recording during MI, and recording during AO. Understanding the muscle activation in each technique will allow us to develop future protocols and intervention plans, improving the quality of care for people who have suffered a stroke.

Aggression: The dark side of mirror neurons sheds light on their functions.

Mirror neurons have been found mainly in neocortical structures of primates and rodents; however, their functions are still debated. A new study has discovered mirror neurons for aggressive behaviors in the ventromedial hypothalamus of mice, an evolutionarily ancient structure, highlighting a new function key for survival.

Effects of integrated action and sensory observation therapy based on mirror neuron and embodied cognition theory on upper limb sensorimotor function in chronic stroke: a study protocol for a randomised controlled trial.

INTRODUCTION: This study protocol aims to explore the effectiveness and neural mechanism of the integration of action observation therapy (AOT) and sensory observation therapy (SOT) for post-stroke patients on upper limb sensorimotor function. METHODS AND ANALYSIS: This is a single-centre, single-blind, randomised controlled trial. A total of 69 patients with upper extremity hemiparesis after stroke will be recruited and randomly divided into an AOT group, a combined action observation and somatosensory stimulation therapy (AOT+SST) group, and a combined AOT and SOT (AOT+SOT) group in a 1:1:1 ratio. Each group will receive 30 min of daily treatment, five times weekly for 4 weeks. The primary clinical outcome will be the Fugl-Meyer Assessment for Upper Extremity. Secondary clinical outcomes will include the Box and Blocks Test, modified Barthel Index and sensory assessment. All clinical assessments and resting-state functional MRI and diffusion tensor imaging data will be obtained at pre-intervention (T1), post-intervention (T2) and 8 weeks of follow-up (T3). ETHICS AND DISSEMINATION: The trial was approved by the Ethics Committee of Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Chinese Traditional Medicine (Grant No. 2020-178). The results will be submitted to a peer-review journal or at a conference. TRIAL REGISTRATION NUMBER: ChiCTR2000040568.

Hypothalamic neurons that mirror aggression.

Social interactions require awareness and understanding of the behavior of others. Mirror neurons, cells representing an action by self and others, have been proposed to be integral to the cognitive substrates that enable such awareness and understanding. Mirror neurons of the primate neocortex represent skilled motor tasks, but it is unclear if they are critical for the actions they embody, enable social behaviors, or exist in non-cortical regions. We demonstrate that the activity of individual VMHvlPR neurons in the mouse hypothalamus represents aggression performed by self and others. We used a genetically encoded mirror-TRAP strategy to functionally interrogate these aggression-mirroring neurons. We find that their activity is essential for fighting and that forced activation of these cells triggers aggressive displays by mice, even toward their mirror image. Together, we have discovered a mirroring center in an evolutionarily ancient region that provides a subcortical cognitive substrate essential for a social behavior.

The effects of action observation training as an add-on rehabilitation strategy on the walking ability of patients with chronic stroke.

OBJECTIVE: Stroke is one of the most debilitating neurological disorders that commonly results in both cognitive and motor dysfunctions. Although the recovery of gait is one of the main goals of patients with stroke, only 50-60% of the patients commonly reach this target. This study aimed to evaluate the effects of action observation training, based on mirror neurons, as an add-on therapy to the conventional physical rehabilitation on the gait performance of patients with stroke. METHODS: Fourteen patients with chronic stroke were randomly assigned to the sham or the experimental group. Both groups received a 40-min conventional physical training following a 12-min observation training depicting exercises for the experimental group but nature pictures for the sham group each session. The patients' walking was recorded using a motion analysis system at baseline and after the 12-session intervention. Spatiotemporal parameters of gait and ground reaction forces were measured. RESULTS: Significant improvements were found in most measured spatiotemporal parameters of gait on the unaffected side of the patients in the experimental group, while in the sham group, the recovery was observed only in the percentage of the stance phase. Regarding the affected side, the stride and step length of the patients in the experimental group were parameters with a significant amelioration. CONCLUSION: The results of this study showed that the action observation training had the potential to improve the walking quality of the patients with hemiplegia in the chronic phase of stroke.

Enhancement of capability for motor imagery using vestibular imbalance stimulation during brain computer interface.

Objective.Motor imagery (MI), based on the theory of mirror neurons and neuroplasticity, can promote motor cortical activation in neurorehabilitation. The strategy of MI based on brain-computer interface (BCI) has been used in rehabilitation training and daily assistance for patients with hemiplegia in recent years. However, it is difficult to maintain the consistency and timeliness of receiving external stimulation to neural activation in most subjects owing to the high variability of electroencephalogram (EEG) representation across trials/subjects. Moreover, in practical application, MI-BCI cannot highly activate the motor cortex and provide stable interaction owing to the weakness of the EEG feature and lack of an effective mode of activation.Approach.In this study, a novel hybrid BCI paradigm based on MI and vestibular stimulation motor imagery (VSMI) was proposed to enhance the capability of feature response for MI. Twelve subjects participated in a group of controlled experiments containing VSMI and MI. Three indicators, namely, activation degree, timeliness, and classification accuracy, were adopted to evaluate the performance of the task.Main results.Vestibular stimulation could significantly strengthen the suppression ofαandßbands of contralateral brain regions during MI, that is, enhance the activation degree of the motor cortex (p< 0.01). Compared with MI, the timeliness of EEG feature-response achieved obvious improvements in VSMI experiments. Moreover, the averaged classification accuracy of VSMI and MI was 80.56% and 69.38%, respectively.Significance.The experimental results indicate that specific vestibular activity contributes to the oscillations of the motor cortex and has a positive effect on spontaneous imagery, which provides a novel MI paradigm and enables the preliminary exploration of sensorimotor integration of MI.

Comparison of the on-line effects of different motor simulation conditions on corticospinal excitability in healthy participants.

In healthy participants, corticospinal excitability is known to increase during motor simulations such as motor imagery (MI), action observation (AO) and mirror therapy (MT), suggesting their interest to promote plasticity in neurorehabilitation. Further comparing these methods and investigating their combination may potentially provide clues to optimize their use in patients. To this end, we compared in 18 healthy participants abductor pollicis brevis (APB) corticospinal excitability during MI, AO or MT, as well as MI combined with either AO or MT. In each condition, 15 motor-evoked potentials (MEPs) and three maximal M-wave were elicited in the right APB. Compared to the control condition, mean normalized MEP amplitude (i.e. MEP/M) increased during MI (P = .003), MT (P < .001) and MT + MI (P < .001), without any difference between the three conditions. No MEP modulation was evidenced during AO or AO + MI. Because MI provided no additional influence when combined with AO or MT, our results may suggest that, in healthy subjects, visual feedback and unilateral movement with a mirror may provide the greatest effects among all the tested motor simulations.

The Motor Basis for Misophonia.

Misophonia is a common disorder characterized by the experience of strong negative emotions of anger and anxiety in response to certain everyday sounds, such as those generated by other people eating, drinking, and breathing. The commonplace nature of these "trigger" sounds makes misophonia a devastating disorder for sufferers and their families. How such innocuous sounds trigger this response is unknown. Since most trigger sounds are generated by orofacial movements (e.g., chewing) in others, we hypothesized that the mirror neuron system related to orofacial movements could underlie misophonia. We analyzed resting state fMRI (rs-fMRI) connectivity (N = 33, 16 females) and sound-evoked fMRI responses (N = 42, 29 females) in misophonia sufferers and controls. We demonstrate that, compared with controls, the misophonia group show no difference in auditory cortex responses to trigger sounds, but do show: (1) stronger rs-fMRI connectivity between both auditory and visual cortex and the ventral premotor cortex responsible for orofacial movements; (2) stronger functional connectivity between the auditory cortex and orofacial motor area during sound perception in general; and (3) stronger activation of the orofacial motor area, specifically, in response to trigger sounds. Our results support a model of misophonia based on "hyper-mirroring" of the orofacial actions of others with sounds being the "medium" via which action of others is excessively mirrored. Misophonia is therefore not an abreaction to sounds, per se, but a manifestation of activity in parts of the motor system involved in producing those sounds. This new framework to understand misophonia can explain behavioral and emotional responses and has important consequences for devising effective therapies.SIGNIFICANCE STATEMENT Conventionally, misophonia, literally "hatred of sounds" has been considered as a disorder of sound emotion processing, in which "simple" eating and chewing sounds produced by others cause negative emotional responses. Our data provide an alternative but complementary perspective on misophonia that emphasizes the action of the trigger-person rather than the sounds which are a byproduct of that action. Sounds, in this new perspective, are only a "medium" via which action of the triggering-person is mirrored onto the listener. This change in perspective has important consequences for devising therapies and treatment methods for misophonia. It suggests that, instead of focusing on sounds, which many existing therapies do, effective therapies should target the brain representation of movement.

A study of EEG mu neurofeedback during action observation.

The mirror system is a brain network that gets activated during action performance and observation. Brain mu waves have been used as a mirror system activity index; however, mu rhythm is prone to contamination by occipital alpha wave activity, thus raising a concern regarding its reliability as an index of the mirror system activity. In this study, we investigated whether mu suppression can be used as an index of neurofeedback training, which influences mirror system activities. Participants observed videos of hand movement under three different conditions: central mu feedback (muFB), occipital alpha feedback (aFB), and simple observation without any feedback (OBS). Results showed that at the 4-5 min mark, mu wave was most significantly suppressed in the central site at muFB. We thus demonstrated the possibility of increasing mu wave suppression in feedback training using a specific stimulus such as motion observation.

Enhancing mirror visual feedback with intermittent theta burst stimulation in healthy adults.

BACKGROUND: Excitatory brain stimulation, in the form of intermittent theta burst stimulation (iTBS), combined with mirror visual feedback (MVF), is hypothesized to promote neuroplasticity and motor performance. OBJECTIVE: This study aimed to investigate the combined effects of iTBS with mirror training (MT) on the MVF-induced sensorimotor event-related desynchronization (ERD) and the non-dominant hand motor performance in healthy adults. METHODS: Eighteen healthy right-handed subjects were randomly assigned to one of three groups (Group 1: iTBS plus MT, Group 2: iTBS plus sham MT, or Group 3: sham iTBS plus MT). For participants in Groups 1 and 3, motor training was performed for 15 minutes for the right hand over four consecutive days, with MVF superimposing on their inactive left hand behind a mirror. Participants in Group 2 received the same right-hand motor training, but the mirror was covered without MVF. iTBS or sham iTBS was applied daily over the right primary motor cortex prior to the training. Electroencephalography at pre/post-training was recorded while participants performed right-hand movement under mirror and direct view. Motor performance was assessed at baseline and post-training. RESULTS: Baseline comparisons demonstrated that a shift in sensorimotor ERD towards the right hemisphere was induced by MVF, in mu-1 (8-10 Hz) (p = 0.002), mu-2 (10-12 Hz) (p = 0.004) and beta-1 (12-16 Hz) (p = 0.049) bands. After the training, participants in Group 1 showed a stronger MVF-induced sensorimotor ERD in mu-1 (p = 0.017) and mu-2 (p = 0.009) bands than those in Group 3. No significant between-group difference in motor outcomes was observed. CONCLUSIONS: iTBS appears to prime subjects' brain to be more receptive to MVF.

[Epilepsy, Mozart and his sonata K.448: is the «Mozart effect¼ therapeutic?] / Epilepsia, Mozart y su sonata K.448: es terapeutico el «efecto Mozart¼?

AIMS: To present a review of the so-called «Mozart effect¼, to explain why Mozart and his sonata K.448 were chosen, and to review the available literature on the treatment of epilepsy with that sonata. DEVELOPMENT: Profuse literature exists on the cerebral mechanisms that allow us to perceive, process and respond to the musical stimulus. Cerebral plasticity, especially in people with musical training, has also been demonstrated. The «Mozart effect¼ arose from the finding that hearing the sonata K.448 improved cognitive abilities, but the fact that these results may be due not to the music itself but to the listener increasing arousal or enjoyment generated controversy. In this context of debate, a large number of papers about the «Mozart effect¼ in the field of epilepsy were published, and are reviewed in this work. CONCLUSIONS: The «Mozart effect¼ has a scientific basis but its nature limits the methodological quality of the research. The music of Mozart, chosen for its exquisite structure, has been able to increase even more the controversy because also it is of the taste of a great majority. It is still far from being consolidated as a non-pharmacological antiepileptic treatment, but it could increase the scientific evidence with studies whose design minimizes the cited confounding factors.

TITLE: Epilepsia, Mozart y su sonata K.448: es terapeutico el «efecto Mozart¼?Objetivos. Presentar una revision del denominado «efecto Mozart¼, explicar por que se eligio a Mozart y su sonata K.448, y repasar la bibliografia disponible sobre el tratamiento de la epilepsia con la citada sonata. Desarrollo. Existe abundante bibliografia sobre los mecanismos cerebrales que nos permiten percibir, procesar y responder al estimulo musical. Tambien se ha demostrado la plasticidad cerebral que, en especial el adiestramiento musical, desencadena. El «efecto Mozart¼ se planteo a raiz de la comprobacion de que la audicion de la sonata K.448 mejoraba habilidades cognitivas, pero el hecho de que esos resultados se puedan deber no a la musica en si, sino a que el oyente aumente su nivel de alerta o disfrute con ella, genero controversia. En este contexto de debate se publico un volumen importante de estudios sobre el «efecto Mozart¼ en el campo de la epilepsia, que se repasan en este trabajo. Conclusiones. El «efecto Mozart¼ tiene base cientifica, pero su propia naturaleza limita la calidad metodologica de los estudios. La musica de Mozart, elegida por su exquisita estructura, ha podido aumentar aun mas la polemica porque tambien resulta del gusto de una gran mayoria. Aun esta lejos de consolidarse como tratamiento antiepileptico no farmacologico, pero podria aumentar la evidencia cientifica con estudios cuyo diseño minimice los factores de confusion citados.

Yoga meditation (YoMed) and its effect on proprioception and balance function in elders who have fallen: A randomized control study.

OBJECTIVE: Yoga has been shown to improve muscle strength, flexibility, and balance. However, the impact of meditation on dynamic factors such as gait, reactive balance and proprioception has yet to be examined. The purpose of this study was to test if a novel yoga meditation program (YoMed) is as effective as a standard proprioceptive training in improving proprioception, balance and power in older individuals who have fallen. DESIGN: Sixteen older persons were randomly assigned to either the YoMed Group (YM) or Proprioception Training Group (PT). Each group received 45 min of training, 3 days per week, for 6 weeks. Pretest and post-test outcome measures were used to quantify the comparative effects of the interventions. SETTING: Research Laboratory. INTERVENTIONS: Yoga meditation and proprioceptive training. MAIN OUTCOME MEASURES: The Balance Error Scoring System (BESS), the Tenetti Balance and Gait Assessment, dynamic posturography, joint position sense, joint kinesthesia and leg extensor power. RESULTS: The primary findings of the study were that neither the YM or PT intervention groups showed statistical improvements in any variable with the exception of the dynamic posturography overall score (DMA), which showed a significant improvement by the YM group (d = 1.238; p = 0.049). Additionally changes in a number of variables that did not reach significance demonstrated effect sizes in the medium to high range. CONCLUSION: These results indicate the potential for the YoMed program to be used as a clinical intervention in older individuals. Given these results a longer study using a larger sample size and individuals at higher risk of falling is warranted.

Positive effects of neurofeedback on autism symptoms correlate with brain activation during imitation and observation.

Autism has been characterized by atypical task-related brain activation and functional connections, coinciding with deficits in sociocommunicative abilities. However, evidence of the brain's experience-dependent plasticity suggests that abnormal activity patterns may be reversed with treatment. In particular, neurofeedback training (NFT), an intervention based on operant conditioning resulting in self-regulation of brain electrical oscillations, has shown increasing promise in addressing abnormalities in brain function and behavior. We examined the effects of ≥ 20 h of sensorimotor mu-rhythm-based NFT in children with high-functioning autism spectrum disorders (ASD) and a matched control group of typically developing children (ages 8-17). During a functional magnetic resonance imaging imitation and observation task, the ASD group showed increased activation in regions of the human mirror neuron system following the NFT, as part of a significant interaction between group (ASD vs. controls) and training (pre- vs. post-training). These changes were positively correlated with behavioral improvements in the ASD participants, indicating that mu-rhythm NFT may be beneficial to individuals with ASD.

Social modeling of eating mediated by mirror neuron activity: A causal model moderated by frontal asymmetry and BMI.

The social modeling of eating effect refers to the consistently demonstrated phenomenon that individuals tend to match their quantity of food intake to their eating companion. The current study sought to explore whether activity within the mirror neuron system (MNS) mediates the social modeling of eating effect as a function of EEG frontal asymmetry and body mass index (BMI). Under the guise of rating empathy, 93 female undergraduates viewed a female video confederate "incidentally" consume either a low or high intake of chips while electroencephalogram (EEG) activity was recorded. Subsequent ad libitum chip consumption was quantified. A first- and second-stage dual moderation model revealed that frontal asymmetry and BMI moderated an indirect effect of model consumption on participants' food consumption as mediated by MNS activity at electrode site C3, a3b3=-0.718, SE=0.365, 95% CI [-1.632, -0.161]. Left frontal asymmetry was associated with greater mu activity and a positive association between model and participant chip consumption, while right frontal asymmetry was associated with less mu activity and a negative association between model and participant consumption. Across all levels of frontal asymmetry, the effect was only significant among those with a BMI at the 50th percentile or lower. Thus, among leaner individuals, the MNS was demonstrated to mediate social modeling of eating, as moderated by frontal asymmetry. These findings are integrated within the normative account of social modeling of eating. It is proposed that the normative framework may benefit from consideration of both conscious and unconscious operation of intake norms.

Action simulation and mirroring in children with autism spectrum disorders.

Mental imitation, perhaps a precursor to motor imitation, involves visual perspective-taking and motor imagery. Research on mental imitation in autism spectrum disorders (ASD) has been rather limited compared to that on motor imitation. The main objective of this fMRI study is to determine the differences in brain responses underlying mirroring and mentalizing networks during mental imitation in children and adolescents with ASD. Thirteen high-functioning children and adolescents with ASD and 15 age-and- IQ-matched typically developing (TD) control participants took part in this fMRI study. In the MRI scanner, participants were shown cartoon pictures of people performing everyday actions (Transitive actions: e.g., ironing clothes but with the hand missing; and Intransitive actions: e.g., clapping hands with the palms missing) and were asked to identify which hand or palm orientation would best fit the gap. The main findings are: 1) both groups performed equally while processing transitive and intransitive actions; 2) both tasks yielded activation in the bilateral inferior frontal gyrus (IFG) and inferior parietal lobule (IPL) in ASD and TD groups; 3) Increased activation was seen in ASD children, relative to TD, in left ventral premotor and right middle temporal gyrus during intransitive actions; and 4) ASD symptom severity positively correlated with activation in left parietal, right middle temporal, and right premotor regions across all subjects. Overall, our findings suggest that regions mediating mirroring may be recruiting more brain resources in ASD and may have implications for understanding social movement through modeling.

Brain stimulation used as biofeedback in neuronal activation of the temporal lobe area in autistic children.

This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA), 10 with intellectual impairments (GDI), and 10 non-autistics (GCN) had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.

Brain stimulation used as biofeedback in neuronal activation of the temporal lobe area in autistic children / Estimulação cerebral usada como biofeedback na ativação neural do lobo temporal em crianças autistas

ABSTRACT This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA), 10 with intellectual impairments (GDI), and 10 non-autistics (GCN) had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.

RESUMO O estudo verificou a capacidade funcional dos neurônios-espelho em crianças autistas. 30 indivíduos, sendo 10 portadores da síndrome autista (GCA), 10 com deficiência intelectual (GDI), e 10 não-autistas (GCN) tiveram registrado o eletroencefalograma da área do cérebro relacionada teoricamente com os neurônios espelho. O procedimento de coleta de dados ocorreu antes e após uma sessão de estimulação cerebral. Durante a segunda coleta de dados, os participantes tiveram de processar alternadamente figuras evocando sentimentos neutros, felizes e tristes. Os resultados provaram que, para todos os grupos, o processo de estimulação de fato produziu ativação adicional na área neural em estudo. O nível de ativação foi relacionada com o formato dos estímulos emocionais. Uma vez que o aumento da ativação ocorreu em um modelo semelhante ao observado para o grupo controle, pode-se sugerir que as pessoas com autismo têm dificuldade em expressar emoções não devido à inexistência de neurônios-espelho.

Selective Influences of Precision and Power Grips on Speech Categorization.

Recent studies have shown that articulatory gestures are systematically associated with specific manual grip actions. Here we show that executing such actions can influence performance on a speech-categorization task. Participants watched and/or listened to speech stimuli while executing either a power or a precision grip. Grip performance influenced the syllable categorization by increasing the proportion of responses of the syllable congruent with the executed grip (power grip-[ke] and precision grip-[te]). Two follow-up experiments indicated that the effect was based on action-induced bias in selecting the syllable.

Motor imagery ability and internal representation of movement in children with probable developmental coordination disorder.

It has been hypothesised that deficits in the functioning of the mirror neuron system (MNS) and internal modelling may contribute to the motor impairments associated with DCD. These processes can be explored behaviourally through motor imagery paradigms. Motor imagery proficiency of children with and without probable DCD (pDCD) was examined using a complex hand rotation task to explore whether motor imagery strategies could be used during more complex tasks. Forty-four boys aged 7-13 years participated, 22 with pDCD (mean = 9.90 years ± 1.57) and 22 controls (mean = 9.68 years ± 1.53). Participants completed the task twice: with and without motor imagery instructions. Stimuli were presented in two rotational axes--palm/back, and eight 45° rotational steps. Both groups showed evidence of following the biomechanical and postural constraints of actual movements. Responses of children with pDCD were slower and less accurate than controls, with group differences increasing alongside task complexity. A greater impact of biomechanical constraints for accuracy was observed in the DCD group. The response characteristics of children with pDCD likely reflects a reduced capacity to mentally manipulate a body schema and reduced visuo-motor processing capabilities. Behaviourally, these processes are linked to MNS and internal modelling function, suggesting deficits in these systems may contribute to the movement difficulties characteristic of DCD.

A holistic approach on the neurological benefits of music.

A holistic perspective on human beings allows health carers to achieve an understanding of all the physiological, psychological and social disturbances of the patient as a whole. Through this article we wish to focus on how music has holistic neurological benefits. Music-therapy interventions can be more accessible and even "self-managed" by the patient's relatives. They can reinforce social cohesion, family ties and patients' self-esteem and thus produce a better quality of life. Overall, it is important to consider the benefits that an evolutionary understanding of musical behaviour and a holistic clinical perspective of the role of music may bring for rehabilitation of a wide range of symptoms and conditions.