104 research outputs found
Brain Control of Functional Reach in Healthy Adults and Stroke Survivors
Purpose: Recovery of the most basic shoulder-flexion/elbow-extension components of functional reach is critical for effective arm function following stroke. In order to understand the mechanisms of motor recovery, it is important to characterize the pattern of brain activation during the reach task. Methods: We evaluated 11 controls and 23 moderately to severely impaired chronic stroke survivors (\u3e6 months), with impaired shoulder flexion and elbow extension. Measures were acquired for Arm Motor Ability Test (AMAT) and functional Magnetic Resonance Imaging (fMRI) during the basic shoulder/elbow reach. Results: First, in controls, lateralization of fMRI signal during the reach task was less pronounced in comparison to other tasks, and even further diminished after stroke (p \u3c 0.05). Second, for the stroke group, centroid locations, for specific ipsilesional (contralateral to working limb) motor-sensory regions and for contralesional (ipsilateral to working arm) somatosensory and SMA regions, were significantly more distant from the centroid location of average healthy controls (p \u3c 0.05). Third, both greater activation volume and greater degree of signal intensity were correlated with better motor function in stroke survivors. Conclusions: These findings can be useful in guiding the development of more targeted brain training methods for recovery of impaired reach coordination
Abnormal Leg Muscle Latencies and Relationship to Dyscoordination and Walking Disability after Stroke
The purpose was to determine timing characteristics of leg muscle latencies for patients following stroke (>12 months) who had persistent coordination and gait deficits, and to determine the relationships among abnormal latencies, dyscoordination, and gait deficits. We compared nine healthy controls and 27 stroke survivors. Surface electromyography measured activation and deactivation latencies of knee flexor and extensor muscles during a ballistic knee flexion task, consistency of latencies across repetitions, and close coupling between agonist and antagonist muscle latencies. We measured Fugl-Meyer (FM) coordination and the functional gait measure, six minute walk test (6MWT). For stroke subjects, there were significant delays of muscle activation and deactivation, abnormal inconsistency, and abnormal decoupled agonist and antagonist activations. There was good correlation between activation latencies and FM and 6MWT. Results suggest abnormal timing characteristics underlie coordination impairment and dysfunctional gait. These abnormal muscle activation and deactivation timing characteristics are important targets for rehabilitation
Construction of Efficacious Gait and Upper Limb Functional Interventions Based on Brain Plasticity Evidence and Model-Based Measures For Stroke Patients
For neurorehabilitation to advance from art to science, it must become evidence-based. Historically, there has been a dearth of evidence from which to construct rehabilitation interventions that are properly framed, accurately targeted, and credibly measured. In many instances, evidence of treatment response has not been sufficiently robust to demonstrate a change in function that is clinically, statistically, and economically important. Research evidence of activity-dependent central nervous system (CNS) plasticity and the requisite motor learning principles can be used to construct an efficacious motor recovery intervention. Brain plasticity after stroke refers to the regeneration of brain neuronal structures and/or reorganization of the function of neurons. Not only can CNS structure and function change in response to injury, but also, the changes may be modified by "activity". For gait training or upper limb functional training for stroke survivors, the "activity" is motor behavior, including coordination and strengthening exercise and functional training that comprise motor learning. Critical principles of motor learning required for CNS activity-dependent plasticity include: close-to-normal movements, muscle activation driving practice of movement; focused attention, repetition of desired movements, and training specificity. The ultimate goal of rehabilitation is to restore function so that a satisfying quality of life can be experienced. Accurate measurement of dysfunction and its underlying impairments are critical to the development of accurately targeted interventions that are sufficiently robust to produce gains, not only in function, but also in quality of life. The Classification of Functioning, Disability, and Health Model (ICF) model of disablement, put forth by the World Health Organization, can provide not only some guidance in measurement level selection, but also can serve as a guide to incorporate function and quality of life enhancement as the ultimate goals of rehabilitation interventions. Based on the evidence and principles of activity-dependent plasticity and motor learning, we developed gait training and upper limb functional training protocols. Guided by the ICF model, we selected and developed measures with characteristics rendering them most likely to capture change in the targeted aspects of intervention, as well as measures having membership not only in the impairment, but also in the Daly and Ruff: Evidence-based stroke motor interventions TheScientificWorldJOURNAL (2007) 7, 2031-2045 2032 functional or life role participation levels contained in the ICF model. We measured response to innovative gait training using a knee flexion coordination measure, coefficient of coordination consistency (ACC) of relative hip/knee (H/K) movement across multiple steps (H/K ACC), and milestones of participation in life role activities. We measured response to upper limb functional training according to measures designed to quantify functional gains in response to treatment targeted at wrist/hand or shoulder elbow training (Arm Motor Ability Test for wrist/hand (AMAT W/H) or shoulder/elbow (AMAT S/E)). We found that there was a statistically significant advantage for adding FES-IM gait training to an otherwise comparable and comprehensive gait training, according to the following measures: H/K ACC, the measure of consistently executed hip/knee coordination during walking; a specific measure of isolated joint knee flexion coordination; and a measure of multiple coordinated gait components. Further, enhanced gains in gait component coordination were robust enough to result in achievement of milestones in participation in life role activities. In the upper limb functional training study, we found that robotics + motor learning (ROB ML; shoulder/elbow robotics practice plus motor learning) produced a statistically significant gain in AMAT S/E; whereas functional electrical stimulation + motor learning (FES ML) did not. We found that FES ML (wrist/hand FES plus motor learning) produced a statistically significant gain in AMAT W/H; whereas ROB ML did not. These results together, support the phenomenon of training specificity in that the most practiced joint movements improved in comparison to joint movements that were practiced at a lesser intensity and frequency. Both ROB ML and FES ML protocols addressed an array of impairments thought to underlie dysfunction. If we are willing to adhere to the ICF model, we accept the challenge that the goal of rehabilitation is life role participation, with functional improvement as in important intermediary step. The ICF model suggests that we intervene at multiple lower levels (e.g., pathology and impairment) in order to improve the higher levels of function and life role participation. The ICF model also suggests that we measure at each level. Not only can we then understand response to treatment at each level, but also, we can begin to understand relationships between levels (e.g., impairment and function). With the ICF model proffering the challenge of restoring life role participation, it then becomes important to design and test interventions that result in impairment gains sufficiently robust to be reflected in functional activities and further, in life role participation. Fortunately, CNS plasticity and associated motor learning principles can serve well as the basis for generating such interventions. These principles were useful in generating both efficacious gait training and efficacious upper limb functional training interventions. These principles led to the use of therapeutic agents (FES and robotics) so that close-to-normal movements could be practiced. These principles supported the use of specific therapeutic agents (BWSTT, FES, and robotics) so that sufficient movement repetition could be provided. These principles also supported incorporation of functional task practice and the demand of attention to task practice within the intervention. The ICF model provided the challenge to restore function and life role participation. The means to that end was provided by principles of CNS plasticity and motor learning
Construction of Efficacious Gait and Upper Limb Functional Interventions Based on Brain Plasticity Evidence and Model-Based Measures For Stroke Patients
Long-Dose Intensive Therapy Is Necessary for Strong, Clinically Significant, Upper Limb Functional Gains and Retained Gains in Severe/Moderate Chronic Stroke
Background. Effective treatment methods are needed for moderate/severely impairment chronic stroke. Objective. The questions were the following: (1) Is there need for long-dose therapy or is there a mid-treatment plateau? (2) Are the observed gains from the prior-studied protocol retained after treatment? Methods. Single-blind, stratified/randomized design, with 3 applied technology treatment groups, combined with motor learning, for long-duration treatment (300 hours of treatment). Measures were Arm Motor Ability Test time and coordination-function (AMAT-T, AMAT-F, respectively), acquired pre-/posttreatment and 3-month follow-up (3moF/U); Fugl-Meyer (FM), acquired similarly with addition of mid-treatment. Findings. There was no group difference in treatment response (P ≥ .16), therefore data were combined for remaining analyses (n = 31; except for FM pre/mid/post, n = 36). Pre-to-Mid-treatment and Mid-to-Posttreatment gains of FM were statistically and clinically significant (P \u3c .0001; 4.7 points and P \u3c .001; 5.1 points, respectively), indicating no plateau at 150 hours and benefit of second half of treatment. From baseline to 3moF/U: (1) FM gains were twice the clinically significant benchmark, (2) AMAT-F gains were greater than clinically significant benchmark, and (3) there was statistically significant improvement in FM (P \u3c .0001); AMAT-F (P \u3c .0001); AMAT-T (P \u3c .0001). These gains indicate retained clinically and statistically significant gains at 3moFU. From posttreatment to 3moF/U, gains on FM were maintained. There were statistically significant gains in AMAT-F (P = .0379) and AMAT-T P = .003
Capability of 2 Gait Measures for Detecting Response to Gait Training in Stroke Survivors: Gait Assessment and Intervention Tool and The Tinetti Gait Scale
Zimbelman J, Daly JJ, Roenigk KL, Butler K, Burdsall R, Holcomb JP. Capability of 2 gait measures for detecting response to gait training in stroke survivors: Gait Assessment and Intervention Tool and the Tinetti Gait Scale. Objective:To characterize the performance of 2 observational gait measures, the Tinetti Gait Scale (TGS) and the Gait Assessment and Intervention Tool (G.A.I.T.), in identifying improvement in gait in response to gait training. Design: In secondary analysis from a larger study of multimodal gait training for stroke survivors, we measured gait at pre-, mid-, and posttreatment according to G.A.I.T. and TGS, assessing their capability to capture recovery of coordinated gait components. Setting: Large medical center. Participants: Cohort of stroke survivors (N=44) greater than 6 months after stroke. Interventions: All subjects received 48 sessions of a multimodal gait-training protocol. Treatment consisted of 1.5 hours per session, 4 sessions per week for 12 weeks, receiving these 3 treatment aspects: (1) coordination exercise, (2) body weight–supported treadmill training, and (3) overground gait training, with 46% of subjects receiving functional electrical stimulation. Main Outcome Measures: All subjects were evaluated with the G.A.I.T. and TGS before and after completing the 48-session intervention. An additional evaluation was performed at midtreatment (after session 24). Results: For the total subject sample, there were significant pre-/post-, pre-/mid-, and mid-/posttreatment gains for both the G.A.I.T. and the TGS. According to the G.A.I.T., 40 subjects (91%) showed improved scores, 2 (4%) no change, and 2 (4%) a worsening score. According to the TGS, only 26 subjects (59%) showed improved scores, 16 (36%) no change, and 1 (2%) a worsening score. For 1 treatment group of chronic stroke survivors, the TGS failed to identify a significant treatment response to gait training, whereas the G.A.I.T. measure was successful. Conclusions: The G.A.I.T. is more sensitive than the TGS for individual patients and group treatment response in identifying recovery of volitional control of gait components in response to gait training
Long-Dose Intensive Therapy Is Necessary for Strong, Clinically Significant, Upper Limb Functional Gains and Retained Gains in Severe/Moderate Chronic Stroke
Background. Effective treatment methods are needed for moderate/severely impairment chronic stroke. Objective. The questions were the following: (1) Is there need for long-dose therapy or is there a mid-treatment plateau? (2) Are the observed gains from the prior-studied protocol retained after treatment? Methods. Single-blind, stratified/randomized design, with 3 applied technology treatment groups, combined with motor learning, for long-duration treatment (300 hours of treatment). Measures were Arm Motor Ability Test time and coordination-function (AMAT-T, AMAT-F, respectively), acquired pre-/posttreatment and 3-month follow-up (3moF/U); Fugl-Meyer (FM), acquired similarly with addition of mid-treatment. Findings. There was no group difference in treatment response (P ≥ .16), therefore data were combined for remaining analyses (n = 31; except for FM pre/mid/post, n = 36). Pre-to-Mid-treatment and Mid-to-Posttreatment gains of FM were statistically and clinically significant (P \u3c .0001; 4.7 points and P \u3c .001; 5.1 points, respectively), indicating no plateau at 150 hours and benefit of second half of treatment. From baseline to 3moF/U: (1) FM gains were twice the clinically significant benchmark, (2) AMAT-F gains were greater than clinically significant benchmark, and (3) there was statistically significant improvement in FM (P \u3c .0001); AMAT-F (P \u3c .0001); AMAT-T (P \u3c .0001). These gains indicate retained clinically and statistically significant gains at 3moFU. From posttreatment to 3moF/U, gains on FM were maintained. There were statistically significant gains in AMAT-F (P = .0379) and AMAT-T P = .003
Comparison of Robotics, Functional Electrical Stimulation, and Motor Learning Methods for Treatment of Persistent Upper Extremity Dysfunction After Stroke: A Randomized Controlled Trial
Objective To compare response to upper-limb treatment using robotics plus motor learning (ML) versus functional electrical stimulation (FES) plus ML versus ML alone, according to a measure of complex functional everyday tasks for chronic, severely impaired stroke survivors. Design Single-blind, randomized trial. Setting Medical center. Participants Enrolled subjects (N=39) were \u3e1 year post single stroke (attrition rate=10%; 35 completed the study). Interventions All groups received treatment 5d/wk for 5h/d (60 sessions), with unique treatment as follows: ML alone (n=11) (5h/d partial- and whole-task practice of complex functional tasks), robotics plus ML (n=12) (3.5h/d of ML and 1.5h/d of shoulder/elbow robotics), and FES plus ML (n=12) (3.5h/d of ML and 1.5h/d of FES wrist/hand coordination training). Main Outcome Measures Primary measure: Arm Motor Ability Test (AMAT), with 13 complex functional tasks; secondary measure: upper-limb Fugl-Meyer coordination scale (FM). Results There was no significant difference found in treatment response across groups (AMAT: P≥.584; FM coordination: P≥.590). All 3 treatment groups demonstrated clinically and statistically significant improvement in response to treatment (AMAT and FM coordination: P≤.009). A group treatment paradigm of 1:3 (therapist/patient) ratio proved feasible for provision of the intensive treatment. No adverse effects. Conclusions Severely impaired stroke survivors with persistent (\u3e1y) upper-extremity dysfunction can make clinically and statistically significant gains in coordination and functional task performance in response to robotics plus ML, FES plus ML, and ML alone in an intensive and long-duration intervention; no group differences were found. Additional studies are warranted to determine the effectiveness of these methods in the clinical setting
An evidence-based review of creative problem solving tools: a practitioner’s resource
Creative problem solving (CPS) requires solutions to be useful and original. Typically, its operations span problem finding, idea generation and critical evaluation. The benefits of training CPS have been extolled in education, industry and government with evidence showing it can enhance performance. However, while such training schemes work, less is known about the specific tools used. Knowing whether a particular tool works or not would provide practitioners with a valuable resource, leading to more effective training schemes, and a better understanding of the processes involved. A comprehensive review was undertaken examining the empirical support of tools used within CPS. Despite the surprising lack of research focusing on the use and success of specific tools some evidence exists to support the effectiveness of a small set. Such findings present practitioners with a potential resource that could be used in a stand-alone setting or possibly combined to create more effective training programmes
Age at first birth in women is genetically associated with increased risk of schizophrenia
Prof. Paunio on PGC:n jäsenPrevious studies have shown an increased risk for mental health problems in children born to both younger and older parents compared to children of average-aged parents. We previously used a novel design to reveal a latent mechanism of genetic association between schizophrenia and age at first birth in women (AFB). Here, we use independent data from the UK Biobank (N = 38,892) to replicate the finding of an association between predicted genetic risk of schizophrenia and AFB in women, and to estimate the genetic correlation between schizophrenia and AFB in women stratified into younger and older groups. We find evidence for an association between predicted genetic risk of schizophrenia and AFB in women (P-value = 1.12E-05), and we show genetic heterogeneity between younger and older AFB groups (P-value = 3.45E-03). The genetic correlation between schizophrenia and AFB in the younger AFB group is -0.16 (SE = 0.04) while that between schizophrenia and AFB in the older AFB group is 0.14 (SE = 0.08). Our results suggest that early, and perhaps also late, age at first birth in women is associated with increased genetic risk for schizophrenia in the UK Biobank sample. These findings contribute new insights into factors contributing to the complex bio-social risk architecture underpinning the association between parental age and offspring mental health.Peer reviewe
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