Speed and Rhythm Affect Temporal Structure of Variability in Reaching Poststroke: A Pilot Study

Temporal structure reveals the potential adaptive strategies employed during upper extremity movements. The authors compared the temporal structure of upper extremity joints under 3 different reaching conditions: preferred speed, fast speed, and reaching with rhythmic auditory cues in 10 individuals poststroke. They also investigated the temporal structure of these 3 reaching conditions in 8 healthy controls to aid in the interpretation of the observed patterns in the poststroke cohort. Approximate entropy (ApEn) was used to measure the temporal structure of the upper extremity joints. ApEn was similar between conditions in controls. After stroke, ApEn was significantly higher for shoulder, elbow, and wrist both at fast speed and with rhythmic cues compared with preferred speed. ApEn at index finger was significantly higher only with rhythmic cues compared with preferred speed. The authors propose that practice reaching at faster speed and with rhythmic cues as a component of rehabilitation interventions may enhance adaptability after stroke

Temporal structure of variability decreases in upper extremity movements post stroke

Methods: Sixteen participants with chronic stroke and nine age-matched controls performed three trials of functional reach-to-grasp. The amount of variability was quantified by computing the standard deviation of shoulder, elbow, wrist and index finger flexion/extension joint angles. The temporal structure of variability was determined by calculating approximate entropy in shoulder, elbow, wrist and index finger flexion/extension joint angles. Findings: Individuals with stroke demonstrated greater standard deviations and significantly reduced approximate entropy values as compared to controls. Furthermore, motor impairments and kinematics demonstrated moderate to strong correlations with temporal structure of variability. Interpretation: Changes in the temporal structure of variability in upper-extremity joint angles suggest that movement patterns used by stroke survivors are less adaptable. This knowledge may yield additional insights into the impaired motor system and suggest better interventions that can enhance upper-extremity movement adaptability

A 3-Month interdisciplinary Process Drama Program to Build Social Skills in Pre-Schoolers with ASD: A Feasibility Study

Objectives: To test the feasibility and effect of an interdisciplinary process drama program targeting social skill development in 3-5 year-old children with Autism Spectrum Disorder (ASD) characteristics To develop a paradigm for testing brain-behavior relationships related to social skills in these children using EEG and testing its ability to detect intervention-related changes. Background: Social skill deficits are a hallmark cause of disability in ASD. Such disability is of critical concern given the rising prevalence (1 in 54 Utah children) of ASD. [1] As children learn through social experiences, difficulty in social interactions can limit development and ability to succeed in school and eventually employment. One possible contributor to social interaction difficulties in ASD is a deficit in theory of mind (ToM), the ability to understand others\u27 perspectives, proposed to rely on memories of cognitive and emotional events that allow one to experience others\u27 situations as if they were one\u27s own. [2.3] Children with ASD have deficits in ToM [2,3] and show aberrant neural activation patterns in areas most typically activated during ToM tasks in healthy children. [4,5] An effective intervention fostering generalizable social skill development in children with ASD remains elusive. We propose to address this need with an interdisciplinary process drama intervention involving collaboration among occupational therapists (OT), theatre faculty/teachers, and speech language pathologists (SLP) to improve social interactions in preschoolers with ASD. Process drama may be an excellent medium for fostering social skill development due to the ability to create specific learning experiences in an autotelic manner [6] in which people experience the embodied cognition and emotions without conscious commitment to abstract social skill improvement goals. The scenes can emphasize social and emotional cues and explicit identification of scene-related feelings for the formation of social cognitive and emotional memories that can be recalled as the basis for later social functioning.[3] Process drama programs foster communication development in typically developing children [7] and a few studies have shown such programs enhance social skills of children aged 8-17 with ASD [8,9] However, targeting process drama intervention in preschool children may have the greatest potential for effect on ToM and subsequent social skill development. The overpruning hypothesis [10] proposes that ASD results from abnormal neural pruning in widespread neural networks, with weaker long-range connections being more vulnerable to major disruption. As neural connections strengthen through experience,[11] providing interventions targeting desired processing will strengthen associated connections making them less susceptible to pruning and resulting in preserved function. Peak synaptic density for auditory and prefrontal cortices, both involved in social skills, occurs between age 3-5 years [11], suggesting an optimal period for strengthening connections through intervention. Impact: The deficits in social skills of people with ASD significantly affect their ability to function in society. These deficits take a large toll on families and on independence and employability of the individual. Finding effective interventions to facilitate social skills would have a large impact on society by reducing disability in this prevalent population. Results: The primary goal of the proposed study is to gather preliminary data on potential utility of an interdisciplinary process drama intervention to improve social skills in children with ASD. We will address the following specific aims: 1) determine the feasibility of: a) the protocol for collecting neural activation data via EEG on preschoolers with ASD characteristics; b) conducting a 3 month, 3x/week process drama intervention program led by a collaborative team of theatre teachers, OTs and SLPs aimed at improving social skills. 2) Determine preliminary effects of this interdisciplinary intervention on: a) increasing positive social behaviors; b) changes in neural activation during social tasks

Predicting Motor Outcomes in Stroke Patients Using Diffusion Spectrum MRI Microstructural Measures

Improved understanding of neuroimaging signal changes and their relation to patient outcomes after ischemic stroke is needed to improve ability to predict motor improvement and make therapy recommendations. The posterior limb of the internal capsule (PLIC) is a hub of afferent and efferent motor signaling and this work proposes new, image-based methods for prognosis based on interhemispheric differences in the PLIC. In this work, nine acute supratentorial ischemic stroke patients with motor impairment received a baseline, 203-direction diffusion brain MRI and a clinical assessment 3–12 days post-stroke and were compared to nine age-matched healthy controls. Asymmetries based on the mean and Kullback-Leibler divergence in the ipsilesional and contralesional PLIC were calculated for diffusion tensor imaging (DTI) and diffusion spectrum imaging (DSI) measures from the baseline MRI. Predictions of upper extremity Fugl-Meyer (FM) scores at 5-weeks follow-up from baseline measures of PLIC asymmetry in diffusion tensor imaging (DTI) and diffusion spectrum imaging (DSI) models were evaluated. For the stroke participants, the baseline asymmetry measures in the PLIC for the orientation dispersion index of the neurite orientation dispersion and density imaging (NODDI) model were highly correlated with upper extremity FM outcomes (r2 = 0.83). Use of DSI and the NODDI orientation dispersion index parameter shows promise of being more predictive of stroke recovery and to help better understand white matter changes in stroke, beyond DTI measures. The new finding that baseline interhemispheric differences in the PLIC calculated from the orientation dispersion index of the NODDI model are highly correlated with upper extremity functional outcomes may lead to improved image-based motor-outcome prediction after middle cerebral artery ischemic stroke

Speed and Rhythm Affect Temporal Structure of Variability in Reaching Poststroke: A Pilot Study.

Temporal structure reveals the potential adaptive strategies employed during upper extremity movements. The authors compared the temporal structure of upper extremity joints under 3 different reaching conditions: preferred speed, fast speed, and reaching with rhythmic auditory cues in 10 individuals poststroke. They also investigated the temporal structure of these 3 reaching conditions in 8 healthy controls to aid in the interpretation of the observed patterns in the poststroke cohort. Approximate entropy (ApEn) was used to measure the temporal structure of the upper extremity joints. ApEn was similar between conditions in controls. After stroke, ApEn was significantly higher for shoulder, elbow, and wrist both at fast speed and with rhythmic cues compared with preferred speed. ApEn at index finger was significantly higher only with rhythmic cues compared with preferred speed. The authors propose that practice reaching at faster speed and with rhythmic cues as a component of rehabilitation interventions may enhance adaptability after stroke

Speed and Rhythm Affect Temporal Structure of Variability in Reaching Poststroke: A Pilot Study

Temporal structure reveals the potential adaptive strategies employed during upper extremity movements. The authors compared the temporal structure of upper extremity joints under 3 different reaching conditions: preferred speed, fast speed, and reaching with rhythmic auditory cues in 10 individuals poststroke. They also investigated the temporal structure of these 3 reaching conditions in 8 healthy controls to aid in the interpretation of the observed patterns in the poststroke cohort. Approximate entropy (ApEn) was used to measure the temporal structure of the upper extremity joints. ApEn was similar between conditions in controls. After stroke, ApEn was significantly higher for shoulder, elbow, and wrist both at fast speed and with rhythmic cues compared with preferred speed. ApEn at index finger was significantly higher only with rhythmic cues compared with preferred speed. The authors propose that practice reaching at faster speed and with rhythmic cues as a component of rehabilitation interventions may enhance adaptability after stroke

Predictors and brain connectivity changes associated with arm motor function improvement from intensive practice in chronic stroke [version 2; referees: 1 approved, 2 approved with reservations]

Background and Purpose: The brain changes that underlie therapy-induced improvement in motor function after stroke remain obscure. This study sought to demonstrate the feasibility and utility of measuring motor system physiology in a clinical trial of intensive upper extremity rehabilitation in chronic stroke-related hemiparesis. Methods: This was a substudy of two multi-center clinical trials of intensive robotic and intensive conventional therapy arm therapy in chronic, significantly hemiparetic, stroke patients. Transcranial magnetic stimulation was used to measure motor cortical output to the biceps and extensor digitorum communus muscles. Magnetic resonance imaging (MRI) was used to determine the cortical anatomy, as well as to measure fractional anisotropy, and blood oxygenation (BOLD) during an eyes-closed rest state. Region-of-interest time-series correlation analysis was performed on the BOLD signal to determine interregional connectivity. Functional status was measured with the upper extremity Fugl-Meyer and Wolf Motor Function Test. Results: Motor evoked potential (MEP) presence was associated with better functional outcomes, but the effect was not significant when considering baseline impairment. Affected side internal capsule fractional anisotropy was associated with better function at baseline. Affected side primary motor cortex (M1) activity became more correlated with other frontal motor regions after treatment. Resting state connectivity between affected hemisphere M1 and dorsal premotor area (PMAd) predicted recovery. Conclusions: Presence of motor evoked potentials in the affected motor cortex and its functional connectivity with PMAd may be useful in predicting recovery. Functional connectivity in the motor network shows a trends towards increasing after intensive robotic or non-robotic arm therapy. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00372411 \& NCT00333983