No effect of prefrontal transcranial direct current stimulation (tDCS) on food craving, food reward and subjective appetite in females displaying mild-to-moderate binge-type behaviour.

Previous work suggests there may be an effect of transcranial direct current stimulation (tDCS) on appetite control in people at risk of overconsumption, however findings are inconsistent. This study aimed to further understand the potential eating behaviour trait-dependent effect of tDCS, specifically in those with binge-type behaviour. Seventeen females (23 ± 7 years, 25.4 ± 3.8 kg m-2) with mild-to-moderate binge eating behaviour completed two sessions of double-blind, randomised and counterbalanced anodal and sham tDCS applied over the right dorsolateral prefrontal cortex at 2.0 mA for 20 min. Subjective appetite visual analogue scales (VAS), the Food Craving Questionnaire-State (FCQ-S), and Leeds Food Preference Questionnaire (LFPQ) were completed pre- and post-tDCS. Participants then consumed a fixed-energy meal, followed by the VAS, FCQ-S and LFPQ. No difference between pre- and post-tDCS scores were found across fullness (p = 0.275, BF10 = 0.040), prospective consumption (p = 0.127, BF10 = 0.063), desire to eat (p = 0.247, BF10 = 0.054) or FCQ-S measures (p = 0.918, BF10 = 0.040) when comparing active and sham protocols. Only explicit liking and wanting for high-fat sweet foods were significantly different between conditions, with increased scores following active tDCS. When controlling for baseline hunger, the significant differences were removed (p = 0.138 to 0.161, BF10 = 0.810 to 1.074). The present data does not support the eating behaviour trait dependency of tDCS in a specific cohort of female participants with mild-to-moderate binge eating scores, and results align with those from individuals with healthy trait scores. This suggests participants with sub-clinical binge eating behaviour do not respond to tDCS. Future work should further explore effects in clinical and sub-clinical populations displaying susceptibility to overconsumption and weight gain.

Effective Transcranial Direct Current Stimulation Parameters for the Modulation of Eating Behavior: A Systematic Literature Review and Meta-Analysis.

OBJECTIVE: This study aimed to consider the effect of differing transcranial direct current stimulation (tDCS) parameters on eating-related measures and how issues with experimental design (e.g., inadequate blinding) or parameters variation may drive equivocal effects. METHODS: Literature searches were conducted across MEDLINE, PsycINFO, Scopus, and Science Direct. Studies using conventional sham-controlled tDCS to modify eating-related measures in adult human participants were included. A total of 1135 articles were identified and screened by two independent authors. Study quality was assessed using the Risk of Bias tool. Random-effects meta-analyses were performed, with subgroup analyses to determine differences between parameter sets. RESULTS: We identified 28 eligible studies; 7 showed low risk of bias, with the remaining studies showing bias arising from issues implementing or reporting blinding protocols. Large variation in applied parameters was found, including montage, current intensity and density, participant and researcher blinding, and the use of online or offline tasks. The application of differing parameters seemed to alter the effects of tDCS on eating-related measures, particularly for current density ( g = -0.25 to 0.31), and when comparing single-session ( g = -0.08 to 0.01) versus multisession protocols ( g = -0.34 to -0.29). Some parameters result in null effects. CONCLUSIONS: The absence of tDCS-mediated change in eating-related measures may be driven by variation in applied parameters. Consistent application of parameters that seem to be effective for modulating eating behavior is important for identifying the potential impact of tDCS. Using the findings of this review, we propose a series of parameters that researchers should apply in their work.

Does sonification of action simulation training impact corticospinal excitability and audiomotor plasticity?

Sonification is a sensory augmentation strategy whereby a sound is associated with, and modulated by, movement. Evidence suggests that sonification could be a viable strategy to maximize learning and rehabilitation. Recent studies investigated sonification of action observation, reporting beneficial effects, especially in Parkinson's disease. However, research on simulation training-a training regime based on action observation and motor imagery, in which actions are internally simulated, without physical execution-suggest that action observation alone is suboptimal, compared to the combined use of action observation and motor imagery. In this study, we explored the effects of sonified action observation and motor imagery on corticospinal excitability, as well as to evaluate the extent of practice-dependent plasticity induced by this training. Nineteen participants were recruited to complete a practice session based on combined and congruent action observation and motor imagery (AOMI) and physical imitation of the same action. Prior to the beginning, participants were randomly assigned to one of two groups, one group (nine participants) completed the practice block with sonified AOMI, while the other group (ten participants) completed the practice without extrinsic auditory information and served as control group. To investigate practice-induced plasticity, participants completed two auditory paired associative stimulation (aPAS) protocols, one completed after the practice block, and another one completed alone, without additional interventions, at least 7 days before the practice. After the practice block, both groups significantly increased their corticospinal excitability, but sonification did not exert additional benefits, compared to non-sonified conditions. In addition, aPAS significantly increased corticospinal excitability when completed alone, but when it was primed by a practice block, no modulatory effects on corticospinal excitability were found. It is possible that sonification of combined action observation and motor imagery may not be a useful strategy to improve corticospinal, but further studies are needed to explore its relationship with performance improvements. We also confirm the neuromodulatory effect of aPAS, but its interaction with audiomotor practice remain unclear.

Sonification of combined action observation and motor imagery: Effects on corticospinal excitability.

Action observation and motor imagery are valuable strategies for motor learning. Their simultaneous use (AOMI) increases neural activity, with related benefits for motor learning, compared to the two strategies alone. In this study, we explored how sonification influences AOMI. Twenty-five participants completed a practice block based on AOMI, motor imagery and physical execution of the same action. Participants were divided into two groups: An experimental group that practiced with sonification during AOMI (sAOMI), and a control group, which did not receive any extrinsic feedback. Corticospinal excitability at rest and during action observation and AOMI was assessed before and after practice, with and without sonification sound, to test the development of an audiomotor association. The practice block increased corticospinal excitability in all testing conditions, but sonification did not affect this. In addition, we found no differences in action observation and AOMI, irrespective of sonification. These results suggest that, at least for simple tasks, sonification of AOMI does not influence corticospinal excitability; In these conditions, sonification may have acted as a distractor. Future studies should further explore the relationship between task complexity, value of auditory information and action, to establish whether sAOMI is a valuable for motor learning.

The effect of transcranial direct current stimulation (tDCS) on food craving, reward and appetite in a healthy population.

The ability to control hedonic appetite is associated with executive functioning, originating in the prefrontal cortex (PFC). These rewarding components of food can override homeostatic mechanisms, potentiating obesogenic behaviours. Indeed, those susceptible to overconsumption appear to have PFC hypo-activation. Transcranial direct current stimulation (tDCS) over the dorsolateral PFC (DLPFC) has been shown to reduce food craving and consumption, potentially via attenuating this reward response. We examined the effects of stimulation on food reward and craving using a healthy-weight cohort. This study is amongst the first to explore the effects of tDCS on explicit and implicit components of reward for different food categories. Twenty-one healthy-weight participants (24 ± 7 years, 22.8 ± 2.3 kg m-2) completed two sessions involving double-blind, randomised and counterbalanced anodal or sham tDCS over the right DLPFC, at 2 mA for 20 min. Food craving (Food Craving Questionnaire-State), reward (Leeds Food Preference Questionnaire), and subjective appetite (100 mm visual analogue scales) were measured pre- and post-tDCS. Eating behaviour trait susceptibility was assessed using the Three Factor Eating Questionnaire-Short Form, Control of Eating Questionnaire, and Food Craving Questionnaire-Trait-reduced. Stimulation did not alter food craving, reward or appetite in healthy-weight participants who displayed low susceptibility to overconsumption, with low trait craving, good craving control, and low uncontrolled eating and emotional eating behaviour. Implicit and explicit reward were reliable measures of hedonic appetite, suggesting these are robust targets for future tDCS research. These findings suggest that applying tDCS over the DLPFC does not change food reward response in individuals not at risk for overconsumption, and future work should focus on those at risk of overconsumption who may be more responsive to the effects of tDCS on hedonic appetite.

Effects of auditory distraction on voluntary movements: exploring the underlying mechanisms associated with parallel processing.

Highly demanding cognitive-motor tasks can be negatively influenced by the presence of auditory stimuli. The human brain attempts to partially suppress the processing of potential distractors in order that motor tasks can be completed successfully. The present study sought to further understand the attentional neural systems that activate in response to potential distractors during the execution of movements. Nineteen participants (9 women and 10 men) were administered isometric ankle-dorsiflexion tasks for 10 s at a light intensity. Electroencephalography was used to assess the electrical activity in the brain, and a music excerpt was used to distract participants. Three conditions were administered: auditory distraction during the execution of movement (auditory distraction; AD), movement execution in the absence of auditory distraction (control; CO), and auditory distraction in the absence of movement (stimulus-only; SO). AD was compared with SO to identify the mechanisms underlying the attentional processing associated with attentional shifts from internal association (task-related) to external (task-unrelated) sensory cues. The results of the present study indicated that the EMG amplitude was not compromised when the auditory stimulus was administered. Accordingly, EEG activity was upregulated at 0.368 s in AD when compared to SO. Source reconstruction analysis indicated that right and central parietal regions of the cortex activated at 0.368 s in order to reduce the processing of task-irrelevant stimuli during the execution of movements. The brain mechanisms that underlie the control of potential distractors during exercise were possibly associated with the activity of the frontoparietal network.

Prospective relationship between hemispheric lateralisation and CD4+ T cells in human immunodeficiency virus type 1.

OBJECTIVES: Neuromodulation of the immune system has been proposed to be influenced by hemispheric lateralisation (HL). The present study tested whether HL predicted CD4+ levels, statistically controlling for confounders. METHODS: Employing two assessments of HL, 68 human immunodeficiency virus (HIV)-1+ patients were followed prospectively. Numerous exclusion criteria and confounder assessments were employed (e.g. age/medication). RESULTS: Left HL significantly positively predicted CD4+ levels at follow-up, and this was qualified by medication (HAART) status: only in HAART-naïve patients did HL predict CD4 levels. Furthermore, HL significantly predicted whether patients had clinically significantly high/low CD4+ counts. CONCLUSIONS: Using a more rigorous methodology than a previous study, the present work partly corroborated the theory of HL influences on immunity, extended it to HIV immunity and identified a possible moderator: HAART medication. Implications for future research and treatments are provided.

Evaluation of the numeric rating scale for perception of effort during isometric elbow flexion exercise.

The aim of the study was to examine the reliability and validity of the numerical rating scale (0-10 NRS) for rating perception of effort during isometric elbow flexion in healthy people. 33 individuals (32 ± 8 years) participated in the study. Three re-test measurements within one session and three weekly sessions were undertaken to determine the reliability of the scale. The sensitivity of the scale following 10 min isometric fatiguing exercise of the elbow flexors as well as the correlation of the effort with the electromyographic (EMG) activity of the flexor muscles were tested. Perception of effort was tested during isometric elbow flexion at 10, 30, 50, 70, 90, and 100% MVC. The 0-10 NRS demonstrated an excellent test-retest reliability [intra class correlation (ICC) = 0.99 between measurements taken within a session and 0.96 between 3 consecutive weekly sessions]. Exploratory curve fitting for the relationship between effort ratings and voluntary force, and underlying EMG showed that both are best described by power functions (y = ax ( b )). There were also strong correlations (range 0.89-0.95) between effort ratings and EMG recordings of all flexor muscles supporting the concurrent criterion validity of the measure. The 0-10 NRS was sensitive enough to detect changes in the perceived effort following fatigue and significantly increased at the level of voluntary contraction used in its assessment (p < 0.001). These findings suggest the 0-10 NRS is a valid and reliable scale for rating perception of effort in healthy individuals. Future research should seek to establish the validity of the 0-10 NRS in clinical settings.

Magnetic versus electrical stimulation in the interpolation twitch technique of elbow flexors.

The study compared peripheral magnetic with electrical stimulation of the biceps brachii m. (BB) in the single pulse Interpolation Twitch Technique (ITT). 14 healthy participants (31±7 years) participated in a within-subjects repeated-measures design study. Single, constant-current electrical and magnetic stimuli were delivered over the motor point of BB with supramaximal intensity (20% above maximum) at rest and at various levels of voluntary contraction. Force measurements from right elbow isometric flexion and muscle electromyograms (EMG) from the BB, the triceps brachii m. (TB) and the abductor pollicis brevis m. (APB) were obtained. The twitch forces at rest and maximal contractions, the twitch force-voluntary force relationship, the M-waves and the voluntary activation (VA) of BB between magnetic and electrical stimulation were compared. The mean amplitude of the twitches evoked at MVC was not significantly different between electrical (0.62 ± 0.49 N) and magnetic (0.81 ± 0.49 N) stimulation (p > 0.05), and the maximum VA of BB was comparable between electrical (95%) and magnetic (93%) stimulation (p > 0. 05). No differences (p >0.05) were revealed in the BB M-waves between electrical (13.47 ± 0.49 mV.ms) and magnetic (12.61 ± 0.58 mV.ms) stimulation. The TB M-waves were also similar (p > 0.05) but electrically evoked APB M-waves were significantly larger than those evoked by magnetic stimulation (p < 0.05). The twitch-voluntary force relationship over the range of MVCs was best described by non-linear functions for both electrical and magnetic stimulation. The electrically evoked resting twitches were consistently larger in amplitude than the magnetically evoked ones (mean difference 3.1 ± 3.34 N, p < 0.05). Reduction of the inter-electrodes distance reduced the twitch amplitude by 6.5 ± 6.2 N (p < 0.05). The fundamental similarities in voluntary activation assessment of BB with peripheral electrical and magnetic stimulation point towards a promising new application of peripheral magnetic stimulation as an alternative to the conventional ITT for the assessment of BB voluntary activation.

Modulating eating behavior with transcranial direct current stimulation (tDCS): A systematic literature review on the impact of eating behavior traits.

Transcranial direct current stimulation (tDCS) is becoming an increasingly popular technique for altering eating behaviors. Recent research suggests a possible eating behavior trait-dependent effect of tDCS. However, studies recruit participant populations with heterogeneous trait characteristics, including "healthy" individuals who do not present with eating behavior traits suggesting susceptibility to overconsumption. The present review considers the effects of tDCS across eating-related measures and explores whether a trait-dependent effect is evident across the literature. A literature search identified 28 articles using sham-controlled tDCS to modify eating-related measures. Random effects meta-analyses were performed, with subgroup analyses to identify differences between "healthy" and trait groups. Trivial overall effects (g = -0.12 to 0.09) of active versus sham tDCS were found. Subgroup analyses showed a more consistent effect for trait groups, with small and moderate effect size (g = -1.03 to 0.60), suggesting tDCS is dependent on participants' eating behavior traits. Larger effect sizes were found for those displaying traits associated with study outcomes (e.g., heightened food cravings). "Healthy" individuals appear to be unresponsive to stimulation. Based on this meta data, future work should recruit those with eating behavior trait susceptibilities to overconsumption, focusing on those who present with traits associated with the outcome of interest.

Safety, feasibility, acceptability and preliminary effects of the Neurofenix platform for Rehabilitation via HOMe Based gaming exercise for the Upper-limb post Stroke (RHOMBUS): results of a feasibility intervention study.

OBJECTIVES: To investigate the safety, feasibility and acceptability of the Neurofenix platform for home-based rehabilitation of the upper limb (UL). DESIGN: A non-randomised intervention design with a parallel process evaluation. SETTING: Participants' homes, South-East England. PARTICIPANTS: Thirty adults (≥18 years), minimum 12-week poststroke, not receiving UL rehabilitation, scoring 9-25 on the Motricity Index (elbow and shoulder), with sufficient cognitive and communicative abilities to participate. INTERVENTIONS: Participants were trained to use the platform, followed by 1 week of graded game-play exposure and 6-week training, aiming for a minimum 45 min, 5 days/week. OUTCOMES: Safety was determined by assessing pain and poststroke fatigue at 8 and 12 weeks, and adverse events (AEs). Impairment, activity and participation outcomes were measured. Intervention feasibility was determined by the amount of specialist training and support required to complete the intervention, time and days spent training, and number of UL movements performed. Acceptability was assessed by a satisfaction questionnaire and semistructured interviews. RESULTS: Participants (14 women; mean (SD) age 60.0 (11.3) years) were a median of 4.9 years poststroke (minimum-maximum: 1-28 years). Twenty-seven participants completed the intervention. The odds of having shoulder pain were lower at 8 weeks (OR 0.45, 95% CI 0.24 to 0.83, p=0.010) and 12 weeks (OR 0.46, 95% CI 0.25 to 0.86, p=0.014) compared with baseline. Fugl-Meyer upper extremity, Motor Activity Log and passive range of movement improved. No other gains were recorded. Poststroke fatigue did not change. Thirty mild and short-term AEs and one serious (unrelated) AE were reported by 19 participants. Participants trained with the platform for a median of 17.4 hours over 7 weeks (minimum-maximum: 0.3-46.9 hours), equating to a median of 149 min per week. The median satisfaction score was 36 out of 40. CONCLUSION: The Neurofenix platform is a safe, feasible and well accepted way to support UL training for people at least three months poststroke. TRIAL REGISTRATION NUMBER: ISRCTN60291412.

Ready Exerciser One: Effects of music and virtual reality on cycle ergometer exercise.

OBJECTIVES: Physical inactivity remains a major global health concern, and researchers have been encouraged to explore the role of technology in the promotion of physical activity. Technologies that deliver audio-visual stimuli are frequently applied in the exercise domain. However, there is a paucity of research that examines the efficacy of modern virtual reality (VR) technology in this context. We investigated the effects of VR and music on affective, perceptual, enjoyment, and cardiac responses to aerobic-type exercise. DESIGN: A fully counterbalanced, within-subjects design was employed. METHODS: A convenience sample of recreationally active adult volunteers (N = 24) completed a 12-min protocol during which they exercised under music, VR, VR-with-music, and control conditions. RESULTS: Analyses indicated a Condition × Time interaction for affective valence and perceived activation. Moreover, a main effect of condition emerged for state attention and perceived enjoyment. The VR and VR-with-music conditions elicited the most positive affective valence, highest levels of perceived activation, greatest number of dissociative thoughts, and most exercise enjoyment. Differences between these two conditions were negligible across the breadth of dependent variables. CONCLUSIONS: The present findings illustrate the efficacy of modern VR technology in the exercise context, applied both with and without musical accompaniment. Additional research is required to assess the degree to which the findings are replicable among sedentary or ageing segments of the population. Given the emerging support pertaining to a positive relationship between affective responses and exercise adherence, VR technology should be considered as a means by which to promote an enjoyable exercise experience.

Dynamic task observation: A gaze-mediated complement to traditional action observation treatment?

Action observation elicits changes in primary motor cortex known as motor resonance, a phenomenon thought to underpin several functions, including our ability to understand and imitate others' actions. Motor resonance is modulated not only by the observer's motor expertise, but also their gaze behaviour. The aim of the present study was to investigate motor resonance and eye movements during observation of a dynamic goal-directed action, relative to an everyday one - a reach-grasp-lift (RGL) action, commonly used in action-observation-based neurorehabilitation protocols. Skilled and novice golfers watched videos of a golf swing and an RGL action as we recorded MEPs from three forearm muscles; gaze behaviour was concurrently monitored. Corticospinal excitability increased during golf swing observation, but it was not modulated by expertise, relative to baseline; no such changes were observed for the RGL task. MEP amplitudes were related to participants' gaze behaviour: in the RGL condition, target viewing was associated with lower MEP amplitudes; in the golf condition, MEP amplitudes were positively correlated with time spent looking at the effector or neighbouring regions. Viewing of a dynamic action such as the golf swing may enhance action observation treatment, especially when concurrent physical practice is not possible.

The feasibility, acceptability and preliminary efficacy of a low-cost, virtual-reality based, upper-limb stroke rehabilitation device: a mixed methods study.

Purpose: To establish feasibility, acceptability, and preliminary efficacy of an adapted version of a commercially available, virtual-reality gaming system (the Personalised Stroke Therapy system) for upper-limb rehabilitation with community dwelling stroke-survivors. Method: Twelve stroke-survivors (nine females, mean age 58 years, [standard deviation 7.1], median stroke chronicity 42 months [interquartile range 34.7], Motricity index 14-25 for shoulder and elbow) were asked to complete nine, 40-min intervention sessions using two activities on the system over 3 weeks. Feasibility and acceptability were assessed through a semi-structured interview, recording of adverse effects, adherence, enjoyment (using an 11-point Likert scale), and perceived exertion (using the BORG scale). Assessments of impairment (Fugl-Meyer Assessment Upper extremity), activity (ABILHAND, Action Research Arm Test, Motor Activity Log-28), and participation (Subjective Index of Physical and Social Outcome) were completed at baseline, following intervention, and at 4-week follow-up. Data were analysed using Thematic Analysis of interview and intervention field-notes and Wilcoxon Signed Ranks. Side-by-side displays were used to integrate findings. Results: Participants received between 175 and 336 min of intervention. Thirteen non-serious adverse effects were reported by five participants. Participants reported a high level of enjoyment (8.1 and 6.8 out of 10) and rated exertion between 11.6 and 12.9 out of 20. Themes of improvements in impairments and increased spontaneous use in functional activities were identified and supported by improvements in all outcome measures between baseline and post-intervention (p < 0.05 for all measures). Conclusions: Integrated findings suggested that the system is feasible and acceptable for use with a group of community-dwelling stroke-survivors including those with moderately-severe disability. Implications for rehabilitation To ensure feasibility of use and maintenance of an appropriate level of challenge, gaming technologies for use in upper-limb stroke rehabilitation should be personalised, dependent on individual need. Through the use of hands-free systems and personalisation, stroke survivors with moderate and moderately-severe levels of upper-limb impairment following stroke are able to use gaming technologies as a means of delivering upper-limb rehabilitation. Future studies should address issues of acceptability, feasibility, and efficacy of personalised gaming technologies for delivery of upper-limb stroke rehabilitation in the home environment. Findings from this study can be used to develop future games and activities suitable for use in stroke rehabilitation.

Reliability, validity and minimal detectable change of the Mini-BESTest in Greek participants with chronic stroke.

OBJECTIVES: This study aimed to investigate the psychometric characteristics of reliability, validity and ability to detect change of a newly developed balance assessment tool, the Mini-BESTest, in Greek patients with stroke. DESIGN: A prospective, observational design study with test-retest measures was conducted. METHODS: A convenience sample of 21 Greek patients with chronic stroke (14 male, 7 female; age of 63 ± 16 years) was recruited. Two independent examiners administered the scale, for the inter-rater reliability, twice within 10 days for the test-retest reliability. Bland Altman Analysis for repeated measures assessed the absolute reliability and the Standard Error of Measurement (SEM) and the Minimum Detectable Change at 95% confidence interval (MDC95%) were established. The Greek Mini-BESTest (Mini-BESTestGR) was correlated with the Greek Berg Balance Scale (BBSGR) for assessing the concurrent validity and with the Timed Up and Go (TUG), the Functional Reach Test (FRT) and the Greek Falls Efficacy Scale-International (FES-IGR) for the convergent validity. RESULTS: The Mini-BESTestGR demonstrated excellent inter-rater reliability (ICC (95%CI) = 0.997 (0.995-0.999, SEM = 0.46) with the scores of two raters within the limits of agreement (meandif = -0.143 ± 0.727, p > 0.05) and test-retest reliability (ICC (95%CI) = 0.966 (0.926-0.988), SEM = 1.53). Additionally, the Mini-BESTestGR yielded very strong to moderate correlations with BBSGR (r = 0.924, p < 0.001), TUG (r = -0.823, p < 0.001), FES-IGR (r = -0.734, p < 0.001) and FRT (r = 0.689, p < 0.001). MDC95 was 4.25 points. CONCLUSION: The exceptionally high reliability and the equally good validity of the Mini-BESTestGR, strongly support its utility in Greek people with chronic stroke. Its ability to identify clinically meaningful changes and falls risk need further investigation.

Cerebral effects of music during isometric exercise: An fMRI study.

A block-design experiment was conducted using fMRI to examine the brain regions that activate during the execution of an isometric handgrip exercise performed at light-to-moderate-intensity in the presence of music. Nineteen healthy adults (7 women and 12 men; Mage = 24.2, SD = 4.9 years) were exposed to an experimental condition (music [MU]) and a no-music control condition (CO) in a randomized order within a single session. Each condition lasted for 10 min and participants were required to execute 30 exercise trials (i.e., 1 trial = 10 s exercise + 10 s rest). Attention allocation, exertional responses, and affective changes were assessed immediately after each condition. The BOLD response was compared between conditions to identify the combined effects of music and exercise on neural activity. The findings indicate that music reallocated attention toward task-unrelated thoughts (d = 0.52) and upregulated affective arousal (d = 0.72) to a greater degree when compared to a no-music condition. The activity of the left inferior frontal gyrus (lIFG) also increased when participants executed the motor task in the presence of music (F = 24.65), and a significant negative correlation was identified between lIFG activity and perceived exertion for MU (limb discomfort: r = -0.54; overall exertion: r = -0.62). The authors hypothesize that the lIFG activates in response to motor tasks that are executed in the presence of environmental sensory stimuli. Activation of this region might also moderate processing of interoceptive signals - a neurophysiological mechanism responsible for reducing exercise consciousness and ameliorating fatigue-related symptoms.

Rehabilitation via HOMe Based gaming exercise for the Upper-limb post Stroke (RHOMBUS): protocol of an intervention feasibility trial.

INTRODUCTION: Effective interventions to promote upper-limb recovery poststroke are characterised by intensive and repetitive movements. However, the repetitive nature of practice may adversely impact on adherence. Therefore, the development of rehabilitation devices that can be used safely and easily at home, and are motivating, enjoyable and affordable is essential to the health and well-being of stroke survivors.The Neurofenix platform is a non-immersive virtual reality device for poststroke upper-limb rehabilitation. The platform uses a hand controller (a NeuroBall) or arm bands (NeuroBands) that facilitate upper-limb exercise via games displayed on a tablet. The Rehabilitation via HOMe Based gaming exercise for the Upper-limb post Stroke trial aims to determine the safety, feasibility and acceptability of the Neurofenix platform for home-based rehabilitation of the upper-limb poststroke. METHODS AND ANALYSIS: Thirty people poststroke will be provided with a Neurofenix platform, consisting of a NeuroBall or NeuroBands (dependent on impairment level), seven specially designed games, a tablet and handbook to independently exercise their upper limb for 7 weeks. Training commences with a home visit from a research therapist to teach the participant how to safely use the device. Outcomes assessed at baseline and 8 weeks and 12 weeks are gross level of disability, pain, objectively measured arm function and impairment, self-reported arm function, passive range of movement, spasticity, fatigue, participation, quality of life (QOL) and health service use. A parallel process evaluation will assess feasibility, acceptability and safety of the intervention through assessment of fidelity to the intervention measured objectively through the Neurofenix platform, a postintervention questionnaire and semistructured interviews exploring participants' experiences of the intervention. The feasibility of conducting an economic evaluation will be determined by collecting data on QOL and resource use. ETHICS AND DISSEMINATION: Ethics approval granted from Brunel University London (10249-MHR-Mar/2018-12322-2). Trial results will be submitted for publication in journals, presented at national and international conferences and distributed to people with stroke. TRIAL REGISTRATION NUMBER: ISRCTN60291412; Pre-results.

Influence of acute inspiratory loading upon diaphragm motor-evoked potentials in healthy humans.

Acute prior activity of the inspiratory muscles can enhance inspiratory muscle strength and reduce effort perception during subsequent inspiratory efforts. However, the mechanisms subserving these changes are poorly understood. Responses to magnetic stimulation in 10 subjects were studied after an acute bout of nonfatiguing inspiratory muscle loading (IML), corresponding to 40% of subjects' initial maximal inspiratory pressure (MIP), and after an acute bout of nonloaded, forced inspiration (NLF). Motor-evoked potentials elicited by cortical stimulation (MEP(c)) and by phrenic nerve stimulation (MEP(p)) were recorded transcutaneously from the diaphragm before, immediately after, and 15 min after two sets of 30 inspiratory efforts, at rest and during an MIP effort. After IML, MIP increased to 113 +/- 3% (SE) of baseline and diaphragm MEP(p) (during MIP) significantly increased (129 +/- 10% of baseline). Diaphragmatic MEP(c) (during MIP), expressed as a percentage of maximal MEP(p), decreased after IML (from 29 +/- 9% to 20 +/- 6%; P = 0.017) and after NLF (from 43 +/- 5% to 31 +/- 5%; P = 0.032). Observations from the biceps brachi demonstrated that changes after IML and NLF were specific to the inspiratory muscle, since no significant changes were observed in biceps force generation or in MEP(p) or MEP(c) amplitudes. These data indicate that after IML increased global inspiratory strength is accompanied by increased peripheral excitability and by a dampening of corticospinal excitability of the diaphragm.

Diaphragm and intercostal surface EMG and muscle performance after acute inspiratory muscle loading.

We examined the effect of an acute bout of submaximal non-fatiguing inspiratory loading (IL) on maximal inspiratory pressure (MIP), and on the activation of the diaphragm (DI) and intercostals (IC) using surface electromyography (sEMG). After baseline measurements, 12 healthy subjects performed two sets of 30 inspiratory efforts at a load equivalent to 40% of their initial MIP. MIP and maximal DI and IC sEMG activity were recorded after the first and second set of IL, and 15 min after task cessation. After IL, MIP reached (+/-S.E.M.) 111+/-4% (P=0.032) of baseline values, and during MIP, DI and IC root mean square (RMS) sEMG amplitude increased significantly above baseline (143+/-21%, P=0.039 and 137+/-33%, P=0.016, respectively). The significant increase in MIP and RMS amplitude after IL suggests that MIP efforts were initially submaximal, and that prior loading enabled full activation. The changes in DI and IC RMS amplitude may also reflect an improvement in the synergy between them during these maximal efforts.

Motor resonance during action observation is gaze-contingent: A TMS study.

When we observe others performing an action, visual input to our mirror neuron system is reflected in the facilitation of primary motor cortex (M1), a phenomenon known as 'motor resonance'. However, it is unclear whether this motor resonance is contingent upon our point-of-gaze. In order to address this issue, we collected gaze data from participants as they viewed an intransitive action - thumb abduction/adduction - under four conditions: with natural gaze behaviour (free viewing) and with their gaze fixated on each of three predetermined loci at various distances from the prime mover. In a control condition, participants viewed little finger movements, also with a fixated gaze. Transcranial magnetic stimulation (TMS) was delivered to M1 and motor evoked potentials (MEPs) were recorded from the right abductor pollicis brevis (APB) and right abductor digiti minimi (ADM). Results showed that, relative to a free viewing condition, a fixated point-of-gaze which maximized transfoveal motion facilitated MEPs in APB. Moreover, during free viewing, saccade amplitudes and APB MEP amplitudes were negatively correlated. These findings indicate that motor resonance is contingent on the observer's gaze behaviour and that, for simple movements, action observation effects may be enhanced by employing a fixed point-of-gaze.