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Recent studies have combined multiple neuroimaging modalities to gain further understanding of the neurobiological substrates of aphasia. Following this line of work, the current study uses machine learning approaches to predict aphasia severity and specific language measures based on a multimodal neuroimaging dataset. A total of 116 individuals with chronic left‐hemisphere stroke were included in the study. Neuroimaging data included task‐based functional magnetic resonance imaging (fMRI), diffusion‐based fractional anisotropy (FA)‐values, cerebral blood flow (CBF), and lesion‐load data. The Western Aphasia Battery was used to measure aphasia severity and specific language functions. As a primary analysis, we constructed support vector regression (SVR) models predicting language measures based on (i) each neuroimaging modality separately, (ii) lesion volume alone, and (iii) a combination of all modalities. Prediction accuracy across models was subsequently statistically compared. Prediction accuracy across modalities and language measures varied substantially (predicted vs. empirical correlation range: r = .00–.67). The multimodal prediction model yielded the most accurate prediction in all cases (r = .53–.67). Statistical superiority in favor of the multimodal model was achieved in 28/30 model comparisons (p‐value range, The current study used machine learning approaches to predict aphasia severity and specific language measures based on a multimodal neuroimaging dataset. Our findings revealed a complementary advantage of integrating several neuroimaging modalities within the same model framework, as compared to any single modality prediction model.

Objective The purpose of this pilot study was to investigate potential changes in brain morphology (cortical thickness and cortical/subcortical volume) accompanying a series of sphenopalatine ganglion (SPG) blockade treatments in chronic migraine with medication overuse headaches (CMw/MOH). Background Local anesthetization of the SPG via intranasal application is used for the treatment for multiple types of headache disorders, including CM. Our previous longitudinal fMRI study revealed improved network connectivity after such treatment. However, the impact of SPG blocks on cortical, subcortical gray matter volume and cortical thickness has yet to be assessed. Methods Using magnetic resonance imaging (MRI), cortical/subcortical volume were measured in 12 chronic migraine patients before and after a series of 12 SPG blocks administered over a 6-week period (2 per week). The average time between MRI assessments was 6 weeks. Targeted, within-subjects t-tests comparing pre-treatment and post-treatment values in specific apriori brain regions of interest, including the hippocampus, amygdala, basal ganglia, somatosensory cortex, temporal cortex and occipital cortex, were used to estimate the impact of repetitive SPG blocks treatment on brain morphology in CMw/MOH. Results Compared to baseline values, the number of moderate/severe headache days per month, HIT-6, PHQ-9 scores and allodynia scores were all significantly improved at the end of treatment. Analysis of MRI data revealed that the volume of the right hippocampus and the right palladium significantly decreased following SPG block treatment, while the volume of the left nucleus accumbens significantly increased following treatment. Cortical thickness in the left temporal pole and left lateral occipito-temporal gyrus significantly decreased following SPG block treatment. Conclusion Our results suggest SPG block treatment is associated with significant symptom improvement as well as significant structural brain changes in regions known to be associated with migraine and chronic pain processing in CMw/MOH.

Objectives Building on mounting evidence distinguishing the neurological basis of different movement imagery abilities (visual versus kinesthetic), this study compared brain activity (i.e., blood flow changes) through functional magnetic resonance imaging elicited by movement imagery in participants self-reporting good and poor imagery abilities with the Movement Imagery Questionnaire-3. Participants also completed the Vividness of Movement Imagery Questionnaire-2. Method: Thirty-seven females (good imagery ability = 18; poor imagery ability = 19) were randomly presented with four experimental conditions (i.e., Kinesthetic, Internal Perspective, External Perspective and Rest) counterbalanced for condition, during three separate 11-min functional brain scans. Results: Kinesthetic and visual (internal/external) subscale mean differences of the Vividness of Movement Imagery Questionnaire-2 favored good imagers and high Movement Imagery Questionnaire-3 inter-scale correlations evidenced convergent validity. As in prior published work, kinesthetic, internal, and external visual imagery elicited distinct patterns of brain activation relative to rest. Overall, the patterns of brain activity in the good and poor imager groups were remarkably similar, indicating that they both generally relied on a similar brain network during movement imagery. Conclusions: Contrary to processing efficiency hypotheses (i.e., neural efficiency hypothesis) we report that during kinesthetic imagery and external visual imagery only, good imagers actually activated a greater number of spatially distinct cortical sites than did poor imagers. Furthermore, research is needed to fully characterize the neural signature of movement imagery in good and poor imagers. Such research is critical to the appropriate creation and proper application of neuroscience-inspired movement imagery-based learning interventions in healthy and clinical populations.

Preclinical studies have shown effects of chronic exposure to addictive drugs on glutamatergic-mediated neuroplasticity in frontostriatal circuitry. These initial findings have been paralleled by human functional magnetic resonance imaging (fMRI) research demonstrating weaker frontostriatal resting-state functional connectivity (rsFC) among individuals with psychostimulant use disorders. However, there is a dearth of human imaging literature describing associations between long-term prescription opioid use, frontostriatal rsFC, and brain morphology among chronic pain patients. We hypothesized that prescription opioid users with chronic pain, as compared with healthy control subjects, would evidence weaker frontostriatal rsFC coupled with less frontostriatal gray matter volume (GMV). Further, those opioid use-related deficits in frontostriatal circuitry would be associated with negative affect and drug misuse. Prescription opioid users with chronic pain (n = 31) and drug-free healthy controls (n = 30) underwent a high-resolution anatomical and an eyes-closed resting-state functional scan. The opioid group, relative to controls, exhibited weaker frontostriatal rsFC, and less frontostriatal GMV in both L.NAc and L.vmPFC. Frontostriatal rsFC partially mediated group differences in negative affect. Within opioid users, L.NAc GMV predicted opioid misuse severity. The current study revealed that prescription opioid use in the context of chronic pain is associated with functional and structural abnormalities in frontostriatal circuitry. These results suggest that opioid use-related abnormalities in frontostriatal circuitry may undergird disturbances in affect that may contribute to the ongoing maintenance of opioid use and misuse. These findings warrant further examination of interventions to treat opioid pathophysiology in frontostriatal circuitry over the course of treatment.

In order to improve our understanding of how pictorial health warning labels (HWLs) influence smoking behavior, we examined whether brain activity helps to explain smoking behavior above and beyond self-reported effectiveness of HWLs. We measured the neural response in the ventromedial prefrontal cortex (vmPFC) and the amygdala while adult smokers viewed HWLs. Two weeks later, participants' self-reported smoking behavior and biomarkers of smoking behavior were reassessed. We compared multiple models predicting change in self-reported smoking behavior (cigarettes per day [CPD]) and change in a biomarkers of smoke exposure (expired carbon monoxide [CO]). Brain activity in the vmPFC and amygdala not only predicted changes in CO, but also accounted for outcome variance above and beyond self-report data. Neural data were most useful in predicting behavioral change as quantified by the objective biomarker (CO). This pattern of activity was significantly modulated by individuals' intention to quit. The finding that both cognitive (vmPFC) and affective (amygdala) brain areas contributed to these models supports the idea that smokers respond to HWLs in a cognitive-affective manner. Based on our findings, researchers may wish to consider using neural data from both cognitive and affective networks when attempting to predict behavioral change in certain populations (e.g. cigarette smokers).

Background Fluid thickening is a well-established management strategy for oropharyngeal dysphagia (OD). However, the effects of thickening agents on the physiology of impaired swallow responses are not fully understood, and there is no agreement on the degree of bolus thickening. Aim To review the literature and to produce a white paper of the European Society for Swallowing Disorders (ESSD) describing the evidence in the literature on the effect that bolus modification has upon the physiology, efficacy and safety of swallowing in adults with OD. Methods A systematic search was performed using the electronic Pubmed and Embase databases. Articles in English available up to July 2015 were considered. The inclusion criteria swallowing studies on adults over 18 years of age; healthy people or patients with oropharyngeal dysphagia; bolus modification; effects of bolus modification on swallow safety (penetration/aspiration) and efficacy; and/or physiology and original articles written in English. The exclusion criteria consisted of oesophageal dysphagia and conference abstracts or presentations. The quality of the selected papers and the level of research evidence were assessed by standard quality assessments. Results At the end of the selection process, 33 articles were considered. The quality of all included studies was assessed using systematic, reproducible, and quantitative tools (Kmet and NHMRC) concluding that all the selected articles reached a valid level of evidence. The literature search gathered data from various sources, ranging from double-blind randomised control trials to systematic reviews focused on changes occurring in swallowing physiology caused by thickened fluids. Main results suggest that increasing bolus viscosity (a) results in increased safety of swallowing, (b) also results in increased amounts of oral and/or pharyngeal residue which may result in post-swallow airway invasion, (c) impacts the physiology with increased lingual pressure patterns, no major changes in impaired airway protection mechanisms, and controversial effects on oral and pharyngeal transit time, hyoid displacements, onset of UOS opening and bolus velocity—with several articles suggesting the therapeutic effect of thickeners is also due to intrinsic bolus properties, (d) reduces palatability of thickened fluids and (e) correlates with increased risk of dehydration and decreased quality of life although the severity of dysphagia may be an confounding factor. Conclusions The ESSD concludes that there is evidence for increasing viscosity to reduce the risk of airway invasion and that it is a valid management strategy for OD. However, new thickening agents should be developed to avoid the negative effects of increasing viscosity on residue, palatability, and treatment compliance. New randomised controlled trials should establish the optimal viscosity level for each phenotype of dysphagic patients and descriptors, terminology and viscosity measurements must be standardised. This white paper is the first step towards the development of a clinical guideline on bolus modification for patients with oropharyngeal dysphagia.

In everyday life, we often make judgments regarding the sequence of events, for example, deciding whether a baseball runner's foot hit the plate before or after the ball hit the glove. Numerous studies have examined the functional correlates of temporal processing using variations of the temporal order judgment and simultaneity judgment (SJ) tasks. To perform temporal order judgment tasks, observers must bind temporal information with identity and/or spatial information relevant to the task itself. SJs, on the other hand, require observers to detect stimulus asynchrony but not the order of stimulus presentation and represent a purer measure of temporal processing. Some previous studies suggest that these temporal decisions rely primarily on right-hemisphere parietal structures, whereas others provide evidence that temporal perception depends on bilateral TPJ or inferior frontal regions (inferior frontal gyrus). Here, we report brain activity elicited by a visual SJ task. Our methods are unique given our use of two orthogonal control conditions, discrimination of spatial orientation and color, which were used to control for brain activation associated with the classic dorsal (“where/how”) and ventral (“what”) visual pathways. Our neuroimaging experiment shows that performing the SJ task selectively activated a bilateral network in the parietal (TPJ) and frontal (inferior frontal gyrus) cortices. We argue that SJ tasks are a purer measure of temporal perception because they do not require observers to process either identity or spatial information, both of which may activate separate cognitive networks.

Dementia is reported to be the overall fourth leading non-communicable cause of death, and accounted for almost two million deaths worldwide (3.5% of the total number) in 2016. Dysphagia and aspiration pneumonia secondary to dementia are the two most serious comorbidities. As the dementia progresses and the severity of an individual's dysphagia increases, the question of whether to commence an artificial nutrition or allow a person to continue to eat and drink orally is raised, both having associated risks. The purpose of this study was to establish current perspectives regarding the method(s) of feeding being used or preferred, once an individual with dementia has reached the end stages of the disease and is unable to swallow safely and efficiently, and ascertain the reasons for the choice made. An online search was completed, and articles published in English available up to April 2018 were considered for inclusion. Hand searching inclusive of the grey literature was also completed to obtain the maximum amount of relevant information. The total yield numbered 1888 studies, and following exclusions, full text studies deemed suitable for review amounted to 18. Themes were generated during the review process, relevant information was extracted, and six main themes emerged: feeding method; aspiration pneumonia; mortality; malnutrition; ethical considerations, and religion. The review indicated that the preferred method of feeding in end-stage dementia was artificial nutrition, in most cases via percutaneous endoscopic gastrostomy. However, despite the perceived advantage of providing artificial nutrition, no convincing evidence was found to support the use of tube feeding in end-stage dementia. In fact, initiating tube feeding was considered to have adverse effects such as aspiration pneumonia, malnutrition and expedited death. Longitudinal research regarding current practice is therefore indicated to establish an optimal procedure for individuals with end-stage dementia and dysphagia.

Graphic health warning labels (HWLs) depicting bodily injury due to smoking are effective for producing changes in affect, cognition and smoking behavior in adult smokers. However, little is known about the effects of repeated presentation of graphic HWL's on the aforementioned processes. The goal of this study was to examine neural and behavioral responses to graphic HWL's and evaluate whether the repeated presentation of graphic HWL's leads to repetition suppression (RS). Smokers (N = 16) performed an event-related HWL cue task while blood oxygen level dependent (BOLD) signal was collected during a functional magnetic resonance imaging (fMRI) experimental session. Consistent with prior literature, graphic HWL's, as compared to scrambled images, elicited increased BOLD response in brain regions involved in self-referential and emotion processing. Importantly, BOLD response at sites in this network diminished during repeated presentation of the same HWL. These findings suggest that while novel graphic HWL's may have a significant effect on smokers' brain activity, repeated presentation may lead to muted responses and thus limit their potential to induce behavioral change.

Context: Sports-related concussions impact between 1.6 and 3.0 million athletes annually in the USA. Although the CDC has qualified sports-related concussion as an epidemic, there is a significant lack of data regarding the best way to assess the long-term effects of concussion, especially in recreational athletes. Objective: To assess the relationship between concussion history and cognitive performance in a group of recreational athletes. Design: Quantitative cross-sectional study. Setting: University of South Carolina, Columbia SC, USA. Participants: Healthy college athletes with no prior history of concussion (n=25) and college athletes with a prior history of at least one concussion (n=25). Main Outcome Measures: Working memory (Paced Visual Serial Addition Test), response inhibition (Go/NoGo task) and decision-making (computer-based visual sorting task). Results: Athletes with a prior history of concussion showed a trend toward lower accuracy on the working memory task, impaired performance in response inhibition and decision making tasks. Factor analysis of the dependent variables derived from a custom-built test battery identified five factors, when entered into a binary logistic model, correctly classified 80% of participants as either having a prior concussion or not. Results of a stepwise linear regression model revealed that the response inhibition factor was significantly correlated with the number of prior concussions. Conclusions: Overall, the results indicated impaired cognitive performance in athletes with a prior history of concussion and show that some, but not all cognitive impairments may vary as a function of the number of prior concussions. These data provide further evidence of the negative consequences of concussion and highlight the vital need to increase research and development efforts aimed at creating apt precautionary measures and rehabilitative methods to minimize the effect of concussions in athletes.

Strenuous exercise leads to a progressive reduction in the performance of voluntary physical exercise. This is due to a process described as fatigue and is defined as the failure to maintain the required or expected power output. While some of this is muscular in origin, fatigue may also be modulated by central mechanisms. Critically, previously reported fatigue-induced changes in cortical activity might actually reflect fMRI BOLD signal drift and/or neural habituation. In order to address this concern, we used a novel fMRI paradigm that enabled us to control for these potential confounds. In a counterbalanced within-subjects design, participants cycled until either lightly fatigued or until they reached a state of general exhaustion on two separate days. On each day, participants were scanned while contracting their hand before, during and after exercising their hand to exhaustion. We identify sites in the anterior ventral premotor cortex (aPMv), insula and postcentral gyrus as critical nodes in the brain network underlying supraspinal fatigue. Our data suggests that activity in the ipsilateral aPMv and adjacent areas in the premotor cortex correlates with both localized fatigue (fatigue specific hand contraction), and generalized, full-body exhaustive fatigue. Additionally, we show that the effects of BOLD signal drift can be modeled and effectively removed from studies that examine supraspinal fatigue. Once the loci of central fatigue are isolated in this way, treatments aimed at modulating activity in these premotor areas may reduce exercise-induced fatigue and perhaps also benefit various clinical conditions in which fatigue is a major symptom.

BACKGROUND: Transcranial direct current stimulation (tDCS) may provide a safe, non-invasive technique for modulating neural excitability during neurorehabilitation. OBJECTIVE: 1) Assess feasibility and potential effectiveness of tDCS as an adjunct to standard upper extremity (UE) physical therapy (PT) for motor impairments resulting from neurological insult. 2) Determine sustainability of improvements over a six month period. METHODS: Five participants with chronic neurologic insult (stroke or traumatic brain injury > 6 months prior) completed 24 sessions (40 minutes, three times/week) of UE-PT combined with bihemispheric tDCS delivered at 1.5 mA over the motor cortex during the first 15 minutes of each PT session. Outcomes were assessed using clinical (UE Fugl-Meyer, Purdue Pegboard, Box and Block, Stroke Impact Scale) and robotic (unimanual and bimanual motor control) measures. Change in scores and associated effects sizes from Pre-test to Post-test and a six month Follow-up were calculated for each participant and group as a whole. RESULTS: Scores on UE Fugl-Meyer, Box and Block, Purdue Pegboard, Stroke Impact Scale, and robotic measures improved from Pre- to Post-test. Improvements on UE Fugl-Meyer, Box and Block, and robotic measures were largely sustained at six months. Combining bihemispheric tDCS with UE-PT in individuals with neurological insult warrants further investi

Objectives To determine the subjective responses of teachers and students to classroom exercise breaks, and how responses varied by duration. Methods This mixed-methods experimental study included focus groups with teachers (N = 8) and 4(th)- and 5(th)-grade students (N = 96). Students participated in 5-, 10-, and 20-minute exercise breaks and 10 minutes of sedentary activity. In an additional exploratory analysis, video-tapes of each condition were coded and compared for positive affect. Results Students and teachers discussed multiple benefits, but teachers discussed barriers to implementing regular breaks of 5-minutes or more. Students exhibited higher positive affect during each exercise condition. Conclusions Classroom exercise breaks are an enjoyable way to increase physical activity, but additional support may be needed to encourage teachers to implement breaks of 5 minutes or longer.

In light of ever-present partisan division in the US political system, it is critical that researchers gain a better under-standing of potential biological differences that exist between self-professed Democrats and Republicans. In the current pilot experiment, we examined differences within the human mirror neuron system (hMNS), a network linked to a host of social and emotional abilities, in a small group of self-identified Republicans and Democrats. We found clear differences between these two groups with respect to resting-state brain connectivity within the hMNS. These neural differences were not systematically related to differences in empathy. Our findings are consistent with the idea that other factors, such as one’s preferential type of social connectivity (broad vs. tight), may have driven the reported findings. These data provide novel insights regarding our knowledge of the biological basis of party identification, and suggest specific directions for future research.

Item does not contain fulltext Observing the movements of another person influences the observer's intention to execute similar movements. However, little is known about how action intentions formed prior to movement planning influence this effect. In the experiment reported here, we manipulated the congruency of movement intentions and action intentions in a pair of jointly acting individuals (i.e., a participant paired with a confederate coactor) and investigated how congruency influenced performance. Overall, participants initiated actions faster when they had the same action intention as the coactor (i.e., when participants and the coactor were pursuing the same conceptual goal). Participants' responses were also faster when their and the coactor's movement intentions were directed to the same spatial location, but only when participants had the same action intention as the coactor. These findings suggest that observers use the same representation to implement their own action intentions that they use to infer other people's action intentions and also that a dynamic, multitiered intentional mechanism is involved in the processing of other people's actions. 6 p.

Historically, data from brain imaging and brain stimulation studies have supported the idea that the processing of observed actions recruits - among other areas - a distinct sub-set of brain sites in the sensory and motor cortices. These empirical findings have initially been linked with the thesis of direct matching as a mechanism of action understanding, i.e., the idea of motor resonance implemented by mirror neurons. In more recent approaches, it has been proposed that the mirror neuron system plays a role in minimizing prediction error when inferring the most likely cause of an observed action. According to these theories, motor resonance is thought to function as predictive coding. Other theoretical accounts suggest that action understanding might result from a hypothesis testing mechanism in which potential goals are continually fed into the system until the correct one is identified. In this review, we will explore the relationship of these theories to specific empirical findings. Finally, we will discuss the implications of these theoretical structures on action observation-based approaches to the optimization of skilled performance in athletes and patients.

Contains fulltext : 77389.pdf (Publisher’s version ) (Open Access) The ability to detect and process errors made by others plays an important role is many social contexts. The capacity to process errors is typically found to rely on sites in the medial frontal cortex. However, it remains to be determined whether responses at these sites are driven primarily by action errors themselves or by the affective consequences normally associated with their commission. Using an experimental paradigm that disentangles action errors and the valence of their affective consequences, we demonstrate that sites in the medial frontal cortex (MFC), including the ventral anterior cingulate cortex (vACC) and pre-supplementary motor area (pre-SMA), respond to action errors independent of the valence of their consequences. The strength of this response was negatively correlated with the empathic concern subscale of the Interpersonal Reactivity Index. We also demonstrate a main effect of self-identification by showing that errors committed by friends and foes elicited significantly different BOLD responses in a separate region of the middle anterior cingulate cortex (mACC). These results suggest that the way we look at others plays a critical role in determining patterns of brain activation during error observation. These findings may have important implications for general theories of error processing.

Contains fulltext : 73537.pdf (Publisher’s version ) (Closed access) An emerging branch of social cognitive neuroscience attempts to unravel the critical cognitive mechanisms that enable humans to engage in joint action. In the current experiment, differences in brain activity in participants engaging in solitary action and joint action were identified using whole brain fMRI while participants performed a virtual bar-balancing task either alone (S), or with the help of a partner in each of two separate joint-action conditions (isomorphic [J(i)] and non-isomorphic [J(n)]). Compared to the performing the task alone, BOLD signal was found to be stronger in both joint-action conditions at specific sites in the human mirror system (MNS). This activation pattern may reflect the demand on participants to simulate the actions of others, integrate their own actions with those of their partners, and compute appropriate responses. Increasing inter-dependence (complementarity) of movements being generated by cooperating individuals (J(n)>J(i)>S) was found to correlate with BOLD signal in the right anterior node of the MNS (pars opercularis), and the area around the right temporoparietal junction (TPJ). These data are relevant to current debates concerning the role of right IFG in complementary action, as well as evolving theories of joint action.

This study extended motor imagery theories by establishing specificity and verification of expected brain activation patterns during imagery. Eighteen female participants screened with the Movement Imagery Questionnaire-3 (MIQ-3) as having good imagery abilities were scanned to determine the neural networks active during an arm rotation task. Four experimental conditions (i.e., KINESTHETIC, INTERNAL Perspective, EXTERNAL Perspective, and REST) were randomly presented (counterbalanced for condition) during three brain scans. Behaviorally, moderate interscale correlations were found between the MIQ-3 and Vividness of Movement Imagery Questionnaire-2, indicating relatedness between the questionnaires. Partially confirming our hypotheses, common and distinct brain activity provides initial biological validation for imagery abilities delineated in the MIQ-3: kinesthetic imagery activated motor-related areas, internal visual imagery activated inferior parietal lobule, and external visual imagery activated temporal, but no occipital areas. Lastly, inconsistent neuroanatomical intraindividual differences per condition were found. These findings relative to recent biological evidence of imagery abilities are highlighted.

Cells in macaque ventral premotor cortex (area F5c) respond to observation or production of specific hand-object interactions. Studies in humans associate the left inferior frontal gyrus, including putative F5 homolog pars opercularis, with observing hand actions. Are these responses related to the realized goal of a prehensile action or to the observation of dynamic hand movements? Rapid, event-related fMRI was used to address this question. Subjects watched static pictures of the same objects being grasped or touched while performing a 1-back orienting task. In all 17 subjects, bilateral inferior frontal cortex was differentially activated in response to realized goals of observed prehensile actions. Bilaterally, precentral gyrus was most frequently activated (82%) followed by pars triangularis (73%) and pars opercularis (65%).

AB Introduction: Mental health-related problems are a significant cause of attrition during basic combat training (BCT). Evidence in civilian populations suggests that physical fitness is associated with psychological benefits in civilians, but little is known about the association between physical fitness and psychological adjustment during BCT. Methods: This study prospectively examined the association between physical fitness and depressive symptoms in 300 BCT soldiers from May to July 2012 at Fort Jackson, Columbia, SC. Soldiers completed a baseline Army Physical Fitness Test (APFT) and survey within 1 wk of arriving at BCT and an end-of-cycle survey after 8 wk of BCT. Soldiers were assigned to the "high" fitness category if they had a passing score on the standard APFT of greater than or equal to 180 out of 300 points. Soldiers scoring less than 180 points on the APFT were assigned to the "low" fitness category. Depressive symptoms were measured using the 20-item Center for Epidemiologic Studies Depression scale. Results: In multivariate analyses, adjusting for baseline demographics, self-reported sleep before BCT, BCT confidence, Army identification, and depressive symptoms, the odds of reporting depressive symptoms were 60% lower for soldiers in the high fitness category (odds ratio, 0.40; 95% confidence interval, 0.19-0.84) compared with soldiers in the low fitness category. Conclusions: Analogous to other positive outcomes of soldier fitness, improvement of soldier physical fitness before BCT might improve soldiers' psychological health outcomes.

Contains fulltext : 76795.pdf (Publisher’s version ) (Closed access) Humans are experts in cooperating with each other when trying to accomplish tasks they cannot achieve alone. Recent studies of joint action have shown that when performing tasks together people strongly rely on the neurocognitive mechanisms that they also use when performing actions individually, that is, they predict the consequences of their co-actor’s behavior through internal action simulation. Context-sensitive action monitoring and action selection processes, however, are relatively underrated but crucial ingredients of joint action. In the present paper, we try to correct the somewhat simplified view on joint action by reviewing recent studies of joint action simulation, monitoring, and selection while emphasizing the intricate interrelationships between these processes. We complement our review by defining the contours of a neurologically plausible computational framework of joint action. 13 p.

Individuals suffering from motor impairments often require physical therapy (PT) to help improve their level of function. Previous investigations suggest that both intermittent theta burst stimulation (iTBS) and bihemispheric transcranial direct current stimulation may increase the speed and extent of motor learning/relearning and that this increase may be related to brain derived neurotrophic factor (BDNF). The purpose of the current study was to explore the feasibility and effectiveness of a novel, non-invasive brain stimulation approach that combined an iTBS primer, and bihemispheric stimulation coupled with motor training. We hypothesized that individuals exposed to this novel treatment would make greater functional improvements than individuals undergoing sham stimulation when tested immediately following, 24-hours, and 7-days post-training. A total of 26 right-handed, healthy young adults were randomly assigned to either a treatment (n = 15) or control group (n = 12). iTBS (20 trains of 10 pulse triplets each delivered at 80% AMT / 50Hz over 191.84 seconds) and bihemispheric tDCS (1.0 ma for 20 minutes) were used as a primer to, and in conjunction with, 20 minutes of motor training, respectively. Our primary outcome measure was performance on the Jebsen-Taylor Hand Function Test. Participants tolerated the combined iTBS/bihemispheric stimulation treatment without complaint. While performance gains in the sham and stimulation group were not significant immediately after training, they were nearly significant 24-hours post training (p = 0.055), and were significant at 7-days post training (p < 0.05). These results suggest that the combined iTBS/bihemispheric stimulation protocol is both feasible and effective. Future research should examine the mechanistic explanation of this approach as well as the potential of using this approach in clinical populations.

Objectives: Gesture-based second languages have become an important tool in the rehabilitation of language-impaired subpopulations. Acquiring the ability to use manual gestures as a means to construct meaningful utterances places unique demands on the brain. This study identified changes in the blood oxygen level-dependent (BOLD) signal associated with the development of gestural fluency using a miniature second-language-based approach. Participants and Methods: Twelve healthy right-handed adults (19-31 years) were trained to produce sequences of meaningful gestures over a period of 2 weeks. Functional magnetic resonance imaging was used to identify brain regions involved in actual and imagined production of meaningful sentences both before (nonfluent production) and after (fluent production) practice. Results: Brain areas showing learning-dependent increases in activity associated with the development of fluency included sites associated with language articulation, while learning-related decreases in the BOLD signal were observed in cortical networks associated with motor imagery, and native language processing. Conclusion: These findings provide novel insights regarding the neural basis of fluency that could inform the design of interventions for treating speech disorders characterized by the loss of fluency.

Humans recognize both the movement (physical) goals and action (conceptual) goals of individuals with whom they are interacting. Here, we assessed whether spontaneous recognition of others’ goals depends on whether the observers control their own behavior at the movement or action level. We also examined the relationship between individual differences in empathy and ASD-like traits, and the processing of other individual’s movement and action goals that are known to be encoded in the “mirroring” and “mentalizing” brain networks. In order to address these questions, we used a computer-based card paradigm that made it possible to independently manipulate movement and action congruency of observed and executed actions. In separate blocks, participants were instructed to select either the right or left card (movement-control condition) or the higher or lower card (action-control condition), while we manipulated action- and movement-congruency of both actors’ goals. An action-congruency effect was present in all conditions and the size of this effect was significantly correlated with self-reported empathy and ASD-like traits. In contrast, movement-congruency effects were only present in the movement-control block and were strongly dependent on action-congruency. These results illustrate that spontaneous recognition of others’ behavior depends on the control scheme that is currently adopted by the observer. The findings suggest that deficits in action recognition are related to abnormal synthesis of perceived movements and prior conceptual knowledge that are associated with activations in the “mirroring” and “mentalizing” cortical networks.

Humans are experts in cooperating in a smooth and proactive manner. Action and intention understanding are critical components of efficient joint action. In the context of the EU Integrated Project JAST [16] we have developed an anthropomorphic robot endowed with these cognitive capacities. This project and respective robot (ARoS) is the focus of the video. More specifically, the results illustrate crucial cognitive capacities for efficient and successful human-robot collaboration such as goal inference, error detection and anticipatory action selection. Results were considered one of the ICT "success stories", JAST: Joint-Action Science and Technology” (Ref. IST-2-003747-IP), FCT FCOMP-01-0124-FEDER-022674”.

This was the first study to compare acute dysphagia service provision directly between the UK and the US. It examined variations in acute dysphagia services between the UK and the US, determined clinicians’ perceptions of their own service and that of their transatlantic counterparts, and elicited the reason for variation. An online survey was distributed to randomly-allocated teaching hospitals in the UK and the US, and speech and language therapists working with acute dysphagia responded anonymously via an automated system. Content analysis was employed to convert free-text responses to numeric data, and then this and existing numeric responses were subjected to descriptive statistical analysis. Variability was high, with the US having on average 0.95 whole time equivalent more clinicians per hospital than the UK. This resulted in an increased number of new patients examined and increased frequency of review of existing patients compared to the UK. In contrast, the UK had significantly increased waiting times with no patient being assessed on the same day as referral (compared to 63.6% of US responses). Notable variation was also seen in objective or instrumental assessment, with most US patients receiving videofluoroscopy or fiberoptic endoscopic evaluation of swallowing (compared to only one UK hospital). Finance was found to be at the root of the variation. However, the more extensive US service was found to be more cost-effective.

Contains fulltext : 90541.pdf (Publisher’s version ) (Open Access) Humans are faster to perform a given action following observation of that same action. Converging evidence suggests that the human mirror neuron system (MNS) plays an important role in this phenomenon. However, the specificity of the neural mechanisms governing this effect remain controversial. Specialist theories of imitation suggest that biological cues are maximally capable of eliciting imitative facilitation. Generalist models, on the other hand, posit a broader role for the MNS in linking visual stimuli with appropriate responses. In the present study, we investigated the validity of these two theoretical approaches by disrupting the left and right inferior frontal gyrus (IFG) during the preparation of congruent (imitative) and incongruent (complementary) actions cued by either biological (hand) or non-biological (static dot) stimuli. Delivery of TMS over IFG abolished imitative response facilitation. Critically, this effect was identical whether actions were cued by biological or non-biological stimuli. This finding argues against theories of imitation in which biological stimuli are treated preferentially and stresses the notion of the IFG as a vital center of general perception–action coupling in the human brain. 7 p.

Contains fulltext : 90611.pdf (Publisher’s version ) (Closed access) Over the past two decades single cell recordings in primates and neuroimaging experiments in humans have uncovered the key proper-ties of visuo-motor mirror neurons located in monkey premotor cortex and parietal cortices as well as homologous areas in the human inferior frontal and inferior parietal cortices which presumably house neurons with similar response properties. One of the most interesting claims regarding the human mirror neuron system (MNS) is that its activity reflects high-level action understanding. If this was the case, one would expect signal in the MNS to differentiate between meaningful and meaningless actions. In the current experiment we tested this prediction using a novel paradigm. Functional magnetic resonance images were collected while participants viewed (i) short films of object-directed actions (ODAs) which were either semantically meaningful, i.e. a hand pressed a stapler or semantically meaningless, i.e. a foot pressed a stapler, (ii) short films of pantomimed actions and (iii) static pictures of objects. Consistent with the notion that the MNS represents high-level action understanding, meaningful and meaningless actions elicited BOLD signal differences at bilateral sites in the supramarginal gyrus (SMG) of the inferior parietal lobule (IPL) where we observed a double dissociation between BOLD response and meaningfullness of actions. Comparison of superadditive responses in the inferior frontal gyrus (IFG) and IPL (supramarginal) regions revealed differential contributions to action understanding. These data further specify the role of specific components of the MNS in understanding object-directed actions.

Contains fulltext : 76972.pdf (Publisher’s version ) (Closed access) The ability to design tailored messages for specific listeners is an important aspect of human communication. The present study investigates whether a mere belief about an addressee’s identity influences the generation and production of a communicative message in a novel, non-verbal communication task. Participants were made to believe they were playing a game with a child or an adult partner, while a confederate acted as both child and adult partners with matched performance and response times. The participants’ belief influenced their behavior, spending longer when interacting with the presumed child addressee, but only during communicative portions of the game, i.e. using time as a tool to place emphasis on target information. This communicative adaptation attenuated with experience, and it was related to personality traits, namely Empathy and Need for Cognition measures. Overall, these findings indicate that novel nonverbal communicative interactions are selected according to a socio-centric perspective, and they are strongly influenced by participants’ traits.

Contains fulltext : 55055.pdf (Publisher’s version ) (Closed access) Humans are frequently confronted with goal-directed tasks that can not be accomplished alone, or that benefit from cooperation with other agents. The relatively new field of social cognitive neuroscience seeks to characterize functional neuroanatomical systems either specifically or preferentially engaged during such joint-action tasks. Based on neuroimaging experiments conducted on critical components of joint action the current paper outlines the functional network upon which joint action is hypothesized to be critically dependant. This network includes brain areas likely to be involved in interpersonal coordination at the action, goal and intentional levels. Experiments focusing specifically on joint-action situations similar to those encountered in real life are required to further specify this model. 18 p.

Contains fulltext : 56945.pdf (Publisher’s version ) (Open Access) Longitudinal changes in brain activity during second language (L2) acquisition of a miniature finite-state grammar, named Wernickese, were identified with functional magnetic resonance imaging (fMRI). Participants learned either a visual sign language form or an auditory-verbal form to equivalent proficiency levels. Brain activity during sentence comprehension while hearing/viewing stimuli was assessed at low, medium, and high levels of proficiency in three separate fMRI sessions. Activation in the left inferior frontal gyrus (Broca's area) correlated positively with improving L2 proficiency, whereas activity in the right-hemisphere (RH) homologue was negatively correlated for both auditory and visual forms of the language. Activity in sequence learning areas including the premotor cortex and putamen also correlated with L2 proficiency. Modality-specific differences in the blood oxygenation level-dependent signal accompanying L2 acquisition were localized to the planum temporale (PT). Participants learning the auditory form exhibited decreasing reliance on bilateral PT sites across sessions. In the visual form, bilateral PT sites increased in activity between Session 1 and Session 2, then decreased in left PT activity from Session 2 to Session 3. Comparison of L2 laterality (as compared to L1 laterality) in auditory and visual groups failed to demonstrate greater RH lateralization for the visual versus auditory L2. These data establish a common role for Broca's area in language acquisition irrespective of the perceptual form of the language and suggest that L2s are processed similar to first languages even when learned after the 'critical period'. The right frontal cortex was not preferentially recruited by visual language after accounting for phonetic/structural complexity and performance. 14 p.

Contains fulltext : 56986.pdf (Publisher’s version ) (Closed access) Determining the relationship between mechanisms involved in action planning and/or execution is critical to understanding the neural bases of skilled behaviors, including tool use. Here we report findings from two fMRI studies of healthy, right-handed adults in which an event-related design was used to distinguish regions involved in planning (i.e. identifying, retrieving and preparing actions associated with a familiar tools' uses) versus executing tool use gestures with the dominant right (experiment 1) and non-dominant left (experiment 2) hands. For either limb, planning tool use actions activates a distributed network in the left cerebral hemisphere consisting of: (i) posterior superior temporal sulcus, along with proximal regions of the middle and superior temporal gyri; (ii) inferior frontal and ventral premotor cortices; (iii) two distinct parietal areas, one located in the anterior supramarginal gyrus (SMG) and another in posterior SMG and angular gyrus; and (iv) dorsolateral prefrontal cortex (DLFPC). With the exception of left DLFPC, adjacent and partially overlapping sub-regions of left parietal, frontal and temporal cortex are also engaged during action execution. We suggest that this left lateralized network constitutes a neural substrate for the interaction of semantic and motoric representations upon which meaningful skills depend. 15 p.

Contains fulltext : 56698.pdf (Publisher’s version ) (Closed access) We assessed the role of the human mirror neuron system (MNS) in complementary actions using functional magnetic resonance imaging while participants prepared to execute imitative or complementary actions. The BOLD signal in the right inferior frontal gyrus and bilateral inferior parietal lobes was greater during preparation of complementary than during imitative actions, suggesting that the MNS may be essential in dynamically coupling action observation to action execution. 2 p.