293 research outputs found
Systematic assessment of training-induced changes in corticospinal output to hand using frameless stereotaxic transcranial magnetic stimulation.
Measuring changes in the characteristics of corticospinal output has become a critical part of assessing the impact of motor experience on cortical organization in both the intact and injured human brain. In this protocol we describe a method for systematically assessing training-induced changes in corticospinal output that integrates volumetric anatomical MRI with transcranial magnetic stimulation (TMS). A TMS coil is sited to a target grid superimposed onto a 3D MRI of cortex using a stereotaxic neuronavigation system. Subjects are then required to exercise the first dorsal interosseus (FDI) muscle on two different tasks for a total of 30 min. The protocol allows for reliably and repeatedly detecting changes in corticospinal output to FDI muscle in response to brief periods of motor training
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Constraint-induced Aphasia Therapy versus Intensive Semantic Treatment in Fluent Aphasia
Objective: To compare the effectiveness of two intensive therapy methods: Constraint- 4 Induced Aphasia Therapy (CIAT) and semantic therapy (BOX).
Method: Nine patients with chronic fluent aphasia participated in a therapy programme 6 to establish behavioral treatment outcomes. Participants were randomly assigned to one of two groups (CIAT or BOX).
Results: Intensive therapy significantly improved verbal communication. However, BOX 9 treatment showed a more pronounced improvement on two communication measures, namely on a standardized assessment for verbal communication, the Amsterdam Nijmegen Everyday Language Test (Blomert, Koster, & Kean, 1995) and on a subjective rating scale, the Communicative Effectiveness Index (Lomas et al., 1989). All 13 participants significantly improved on one (or more) subtests of the Aachen Aphasia Test (Graetz et al., 1992), an impairment-focused assessment. There was a treatment-specific effect. Therapy with BOX had a significant effect on language comprehension and on semantics, while of CIAT affected language production and phonology.
Conclusion: The findings indicate that in patients with fluent aphasia (1) intensive treatment has a significant effect on language and verbal communication, (2) intensive therapy results in selective treatment effects and (3) an intensive semantic treatment shows a more striking mean improvement on verbal communication in comparison to communication-based CIAT-treatment
Memory consolidation in the cerebellar cortex
Several forms of learning, including classical conditioning of the eyeblink, depend upon the cerebellum. In examining mechanisms of eyeblink conditioning in rabbits, reversible inactivations of the control circuitry have begun to dissociate aspects of cerebellar cortical and nuclear function in memory consolidation. It was previously shown that post-training cerebellar cortical, but not nuclear, inactivations with the GABA(A) agonist muscimol prevented consolidation but these findings left open the question as to how final memory storage was partitioned across cortical and nuclear levels. Memory consolidation might be essentially cortical and directly disturbed by actions of the muscimol, or it might be nuclear, and sensitive to the raised excitability of the nuclear neurons following the loss of cortical inhibition. To resolve this question, we simultaneously inactivated cerebellar cortical lobule HVI and the anterior interpositus nucleus of rabbits during the post-training period, so protecting the nuclei from disinhibitory effects of cortical inactivation. Consolidation was impaired by these simultaneous inactivations. Because direct application of muscimol to the nuclei alone has no impact upon consolidation, we can conclude that post-training, consolidation processes and memory storage for eyeblink conditioning have critical cerebellar cortical components. The findings are consistent with a recent model that suggests the distribution of learning-related plasticity across cortical and nuclear levels is task-dependent. There can be transfer to nuclear or brainstem levels for control of high-frequency responses but learning with lower frequency response components, such as in eyeblink conditioning, remains mainly dependent upon cortical memory storage
Task-specific reach-to-grasp training after stroke: Development and description of a home-based intervention
© The Author(s) 2015. This series of articles for rehabilitation in practice aims to cover a knowledge element of the rehabilitation medicine curriculum. Nevertheless they are intended to be of interest to a multidisciplinary audience. The competency addressed in this article is to transparently describe the process of developing a complex intervention for people after stroke as part of a feasibility randomised controlled trial. Objective: To describe and justify the development of a home-based, task-specific upper limb training intervention to improve reach-to-grasp after stroke and pilot it for feasibility and acceptability prior to a randomized controlled trial. Intervention description: The intervention is based on intensive practice of whole reach-to-grasp tasks and part-practice of essential reach-to-grasp components. A 'pilot' manual of activities covering the domains of self-care, leisure and productivity was developed for the feasibility study. The intervention comprises 14 hours of therapist-delivered sessions over six weeks, with additional self-practice recommended for 42 hours (i.e. one hour every day). As part of a feasibility randomized controlled trial, 24 people with a wide range of upper limb impairment after stroke experienced the intervention to test adherence and acceptability. The median number of repetitions in one-hour therapist-delivered sessions was 157 (interquartile range IQR 96-211). The amount of self-practice was poorly documented. Where recorded, the median amount of practice was 30 minutes (interquartile range 22-45) per day. Findings demonstrated that the majority of participants found the intensity, content and level of difficulty of the intervention acceptable, and the programme to be beneficial. Comments on the content and presentation of the self-practice material were incorporated in a revised 'final' intervention manual. Discussion: A comprehensive training intervention to improve reach-to-grasp for people living at home after stroke has been described in accordance with the Template for Intervention Description and Replication (TIDieR) reporting guidelines. The intervention has been piloted, and found to be acceptable and feasible in the home setting. Trial registration: ISRCTN5671658
A brief early intervention for adolescent depression that targets emotional mental images and memories: protocol for a feasibility randomised controlled trial (IMAGINE trial)
This is the final version of the article. Available from BioMed Central via the DOI in this record.Background: Adolescent depression is common and impairing. There is an urgent need to develop early interventions to prevent depression becoming entrenched. However, current psychological interventions are difficult to access and show limited evidence of effectiveness. Schools offer a promising setting to enhance access to interventions, including reducing common barriers such as time away from education. Distressing negative mental images and a deficit in positive future images, alongside overgeneral autobiographical memories, have been implicated in depression across the lifespan, and interventions targeting them in adults have shown promise. Here, we combine techniques targeting these cognitive processes into a novel, brief psychological intervention for adolescent depression. This feasibility randomised controlled trial will test the feasibility and acceptability of delivering this imagery-based cognitive behavioural intervention in schools. Methods/design: Fifty-six adolescents (aged 16-18) with high symptoms of depression will be recruited from schools. Participants will be randomly allocated to the imagery-based cognitive behavioural intervention (ICBI) or the control intervention, non-directive supportive therapy (NDST). Data on feasibility and acceptability will be recorded throughout, including data on recruitment, retention and adherence rates as well as adverse events. In addition, symptom assessment will take place pre-intervention, post-intervention and at 3-month follow-up. Primarily, the trial aims to establish whether it is feasible and acceptable to carry out this project in a school setting. Secondary objectives include collecting data on clinical measures, including depression and anxiety, and measures of the mechanisms proposed to be targeted by the intervention. The acceptability of using technology in assessment and treatment will also be evaluated. Discussion: Feasibility, acceptability and symptom data for this brief intervention will inform whether an efficacy randomised controlled trial is warranted and aid planning of this trial. If this intervention is shown in a subsequent definitive trial to be safe, clinically effective and cost-effective, it has potential to be rolled out as an intervention and so would significantly extend the range of therapies available for adolescent depression. This psychological intervention draws on cognitive mechanism research suggesting a powerful relationship between emotion and memory and uses imagery as a cognitive target in an attempt to improve interventions for adolescent depression. Trial registration: ISRCTN85369879.This study represents independent research from a Clinical Doctoral Research Fellowship (Dr Victoria Pile, ICA-CDRF-2015-01-007) supported by the National Institute for Health Research and Health Education England
Gene Expression Changes in the Motor Cortex Mediating Motor Skill Learning
The primary motor cortex (M1) supports motor skill learning, yet little is known about the genes that contribute to motor cortical plasticity. Such knowledge could identify candidate molecules whose targeting might enable a new understanding of motor cortical functions, and provide new drug targets for the treatment of diseases which impair motor function, such as ischemic stroke. Here, we assess changes in the motor-cortical transcriptome across different stages of motor skill acquisition. Adult rats were trained on a gradually acquired appetitive reach and grasp task that required different strategies for successful pellet retrieval, or a sham version of the task in which the rats received pellet reward without needing to develop the reach and grasp skill. Tissue was harvested from the forelimb motor-cortical area either before training commenced, prior to the initial rise in task performance, or at peak performance. Differential classes of gene expression were observed at the time point immediately preceding motor task improvement. Functional clustering revealed that gene expression changes were related to the synapse, development, intracellular signaling, and the fibroblast growth factor (FGF) family, with many modulated genes known to regulate synaptic plasticity, synaptogenesis, and cytoskeletal dynamics. The modulated expression of synaptic genes likely reflects ongoing network reorganization from commencement of training till the point of task improvement, suggesting that motor performance improves only after sufficient modifications in the cortical circuitry have accumulated. The regulated FGF-related genes may together contribute to M1 remodeling through their roles in synaptic growth and maturation.McGovern Institute for Brain Research at MITNational Institutes of Health (U.S.) ((NIH grant 1-RC1-NS068103-01)National Institutes of Health (U.S.) (NIH grant R01-MH084966)Roberto Rocca Education Program (Fellowship)Massachusetts Institute of Technology. Undergraduate Research Opportunities Program (Fellowship)Italy. Ministero dell'istruzione, dell'università e della ricerca (MIUR grant RBIN04H5AS)Italy. Ministero dell'istruzione, dell'università e della ricerca (MIUR grant RBLA03FLJC)Italy. Ministero dell'istruzione, dell'università e della ricerca (FIRB n. RBAP10L8TY
TCR cross-reactivity and allorecognition: new insights into the immunogenetics of allorecognition
Alloreactive T cells are core mediators of graft rejection and are a potent barrier to transplantation tolerance. It was previously unclear how T cells educated in the recipient thymus could recognize allogeneic HLA molecules. Recently it was shown that both naïve and memory CD4+ and CD8+ T cells are frequently cross-reactive against allogeneic HLA molecules and that this allorecognition exhibits exquisite peptide and HLA specificity and is dependent on both public and private specificities of the T cell receptor. In this review we highlight new insights gained into the immunogenetics of allorecognition, with particular emphasis on how viral infection and vaccination may specifically activate allo-HLA reactive T cells. We also briefly discuss the potential for virus-specific T cell infusions to produce GvHD. The progress made in understanding the molecular basis of allograft rejection will hopefully be translated into improved allograft function and/or survival, and eventually tolerance induction
Wristband accelerometers to motivate arm exercise after stroke (WAVES): study protocol for a pilot randomized controlled trial
BACKGROUND: Loss of upper limb function affects up to 85 % of acute stroke patients. Recovery of upper limb function requires regular intensive practise of specific upper limb tasks. To enhance intensity of practice interventions are being developed to encourage patients to undertake self-directed exercise practice. Most interventions do not translate well into everyday activities and stroke patients continue to find it difficult remembering integration of upper limb movements into daily activities. A wrist-worn device has been developed that monitors and provides ‘live’ upper limb activity feedback to remind patients to use their stroke arm in daily activities (The CueS wristband). The aim of this trial is to assess the feasibility of a multi-centre, observer blind, pilot randomised controlled trial of the CueS wristband in clinical stroke services. METHODS/DESIGN: This pilot randomised controlled feasibility trial aims to recruit 60 participants over 15 months from North East England. Participants will be within 3 months of stroke which has caused new reduced upper limb function and will still be receiving therapy. Each participant will be randomised to an intervention or control group. Intervention participants will wear a CueS wristband (between 8 am and 8 pm) providing “live” feedback towards pre-set movement goals through a simple visual display and vibration prompts whilst undertaking a 4-week upper limb therapy programme (reviewed twice weekly by an occupational/physiotherapist). Control participants will also complete the 4-week upper limb therapy programme but will wear a ‘sham’ CueS wristband that monitors upper limb activity but provides no feedback. Outcomes will determine study feasibility in terms of recruitment, retention, adverse events, adherence and collection of descriptive clinical and accelerometer motor performance data at baseline, 4 weeks and 8 weeks. DISCUSSION: The WAVES study will address an important gap in the evidence base by reporting the feasibility of undertaking an evaluation of emerging and affordable technology to encourage impaired upper limb activity after stroke. The study will establish whether the study protocol can be supported by clinical stroke services, thereby informing the design of a future multi-centre randomised controlled trial of clinical and cost-effectiveness. TRIAL REGISTRATION: ISRCTN:82306027. Registered 12 July 2016. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-016-1628-2) contains supplementary material, which is available to authorized users
Factors contributing to posttraumatic growth and its buffering effect in adult chidren of cancer patients undergoing treatment
This study examined relationships among demographic, clinical,
and psychosocial variables in adult children of cancer patients.
Two hundred and fourteen participants completed measures of
posttraumatic growth (PTG), distress, posttraumatic stress disorder
(PTSD) symptoms, social support, and family functioning. Significant
gender differences in all PTG dimensions were found, as well
as associations among PTG, gender, parental dependency, distress,
PTSD, and family functioning. Social support was not a mediator
in the relationship between gender and PTG. Gender, education,
disease duration, dependency, distress, and family flexibility predicted
PTG. Finally, PTG had amoderating effect in the relationship
between distress and PTSD/social support. These results may guide
psychosocial interventions in this population.Fundação para a Ciência e Tecnologia (FCT
An Animal Model of Emotional Blunting in Schizophrenia
Schizophrenia is often associated with emotional blunting—the diminished ability to respond to emotionally salient stimuli—particularly those stimuli representative of negative emotional states, such as fear. This disturbance may stem from dysfunction of the amygdala, a brain region involved in fear processing. The present article describes a novel animal model of emotional blunting in schizophrenia. This model involves interfering with normal fear processing (classical conditioning) in rats by means of acute ketamine administration. We confirm, in a series of experiments comprised of cFos staining, behavioral analysis and neurochemical determinations, that ketamine interferes with the behavioral expression of fear and with normal fear processing in the amygdala and related brain regions. We further show that the atypical antipsychotic drug clozapine, but not the typical antipsychotic haloperidol nor an experimental glutamate receptor 2/3 agonist, inhibits ketamine's effects and retains normal fear processing in the amygdala at a neurochemical level, despite the observation that fear-related behavior is still inhibited due to ketamine administration. Our results suggest that the relative resistance of emotional blunting to drug treatment may be partially due to an inability of conventional therapies to target the multiple anatomical and functional brain systems involved in emotional processing. A conceptual model reconciling our findings in terms of neurochemistry and behavior is postulated and discussed
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