Gender Representation on Editorial Boards of JAMA Network Journals.

Objective: Underrepresentation of women on editorial boards of biomedical journals has occurred for decades. The JAMA Network Journals have substantial and broad impact on advances in the biomedical sciences. We sought to determine the current status of gender representation on editorial boards of the 12 JAMA Network Journals. Methods: The gender of each editorial board member of the 12 JAMA Network Journals was classified based on review of online sources. The percentage of women on each board (i.e., number of women relative to total members) was calculated and compared to gender equity and parity benchmarks. The gender equity benchmark for each journal was defined as the percentage of women physicians in the medical specialty reflecting the journal's content based on Association of American Medical Colleges data. The gender parity benchmark for all journals was defined as 50% women. Results: There was considerable variation in the representation of women on the editorial boards of the JAMA Network Journals relative to gender equity and parity benchmarks. Women were underrepresented on 50% (6 of 12) of boards relative to gender equity and 67% (8 of 12) of boards relative to gender parity. Conclusions: Women were found to be underrepresented on 50% or more of the editorial boards of the JAMA Network Journals. This finding reflects gender inequities in academic publishing and the broader biomedical enterprise, which limits advances in the biomedical sciences and health care. Those JAMA Network Journals that continue to underrepresent women on their editorial boards are urged to remediate this longstanding issue.

Workplace Belonging of Women Healthcare Professionals Relates to Likelihood of Leaving.

Purpose: There is a high rate of attrition of professionals from healthcare institutions, which threatens the economic viability of these institutions and the quality of care they provide to patients. Women professionals face particular challenges that may lower their sense of belonging in the healthcare workplace. We sought to test the hypothesis that workplace belonging of women healthcare professionals relates to the likelihood that they expect to leave their institution. Methods: Participants of a continuing education course on women's leadership skills in health care completed a survey about their experiences of belonging in workplace and their likelihood of leaving that institution within the next 2 years. An association between workplace belonging (measured by the cumulative number of belonging factors experienced, scale 0-10) and likelihood of leaving (measured on a 5-point Likert scale) was evaluated using ordinal logistic regression. The relative importance of workplace belonging factors in predicting the likelihood of leaving was assessed using dominance analysis. Results: Ninety-nine percent of survey participants were women, and 63% were clinicians. Sixty-one percent of participants reported at least a slight likelihood of leaving their healthcare institution within the next 2 years. Greater workplace belonging was found to be associated with a significant reduction in the reported likelihood of leaving their institution after accounting for the number of years having worked in their current institution, underrepresented minority status, and the interaction between the latter two covariates. The workplace belonging factor found to be most important in predicting the likelihood of leaving was the belief that there was an opportunity to thrive professionally in the institution. Belonging factors involving feeling able to freely share thoughts and opinions were also found to be of relatively high importance in predicting the likelihood of leaving. Conclusion: Greater workplace belonging was found to relate significantly to a reduced likelihood of leaving their institution within the next 2 years. Our findings suggest that leaders of healthcare organizations might reduce attrition of women by fostering workplace belonging with particular attention to empowering professional thriving and creating a culture that values open communication.

Disruptions in Structural and Functional Connectivity Relate to Poststroke Fatigue.

Introduction: Poststroke fatigue (PSF) is a disabling condition with unclear etiology. The brain lesion is thought to be an important causal factor in PSF, although focal lesion characteristics such as size and location have not proven to be predictive. Given that the stroke lesion results not only in focal tissue death but also in widespread changes in brain networks that are structurally and functionally connected to damaged tissue, we hypothesized that PSF relates to disruptions in structural and functional connectivity. Materials and Methods: Twelve patients who incurred an ischemic stroke in the middle cerebral artery (MCA) territory 1-3 years prior, and currently experiencing a range of fatigue severity, were enrolled. The patients underwent structural and resting-state functional magnetic resonance imaging (MRI). The structural MRI data were used to measure structural disconnection of gray matter resulting from lesion to white matter pathways. The functional MRI data were used to measure network functional connectivity. Results: The patients showed structural disconnection in varying cortical and subcortical regions. Fatigue severity correlated significantly with structural disconnection of several frontal cortex regions in the ipsilesional (IL) and contralesional hemispheres. Fatigue-related structural disconnection was most severe in the IL rostral middle frontal cortex. Greater structural disconnection of a subset of fatigue-related frontal cortex regions, including the IL rostral middle frontal cortex, trended toward correlating significantly with greater loss in functional connectivity. Among identified fatigue-related frontal cortex regions, only the IL rostral middle frontal cortex showed loss in functional connectivity correlating significantly with fatigue severity. Conclusion: Our results provide evidence that loss in structural and functional connectivity of bihemispheric frontal cortex regions plays a role in PSF after MCA stroke, with connectivity disruptions of the IL rostral middle frontal cortex having a central role. Impact statement Poststroke fatigue (PSF) is a common disabling condition with unclear etiology. We hypothesized that PSF relates to disruptions in structural and functional connectivity secondary to the focal lesion. Using structural and resting-state functional connectivity magnetic resonance imaging (MRI) in patients with chronic middle cerebral artery (MCA) stroke, we found frontal cortex regions in the ipsilesional (IL) and contralesional hemispheres with greater structural disconnection correlating with greater fatigue. Among these fatigue-related cortices, the IL rostral middle frontal cortex showed loss in functional connectivity correlating with fatigue. These findings suggest that disruptions in structural and functional connectivity play a role in PSF after MCA stroke.

A pilot [11C]PBR28 PET/MRI study of neuroinflammation and neurodegeneration in chronic stroke patients.

Neuroinflammation occurs in response to acute ischemic stroke, and has been speculated to underlie secondary poststroke pathologies, such as depression, that often develop over time poststroke. However, no study has examined whether neuroinflammation is present in chronic stroke patients (e.g., â€‹≥ â€‹1 year poststroke). This study tested whether neuroinflammation is present in chronic stroke patients, and is associated with neurodegeneration, using [11C]PBR28 PET and diffusion MRI. Eight patients with middle cerebral artery (MCA) ischemic stroke incurred 1-3 years prior and 16 healthy controls underwent [11C]PBR28 PET to measure glial activation and diffusion MRI to measure microstructural integrity by mean diffusivity (MD) and fractional anisotropy (FA) using an integrated PET/MRI scanner. Group differences in [11C]PBR28 binding, MD and FA were analyzed voxelwise across the whole brain excluding the infarct zone defined as voxels containing the infarct in any patient. Compared to controls, patients showed elevations in [11C]PBR28 binding in several brain regions outside the infarct zone, including regions with presumed direct neuroanatomical connections to the infarct (e.g., ipsilesional internal capsule and thalamus) and those without known direct connections (e.g., contralesional thalamus and cingulate gyrus). Patients also showed widespread elevations in MD, with a subset of these regions having reduced FA. In patients, MD was more elevated in regions with co-localized elevations in [11C]PBR28 binding than in contralateral regions without elevations in [11C]PBR28 binding. This pilot study supports the presence of extensive glial activation along with widespread loss in microstructural integrity in non-infarcted tissue in a cohort of patients with chronic MCA stroke. The loss in microstructural integrity was greater in regions with co-localized glial activation. It is possible that stroke risk factors (e.g., hypertension) contributed to these tissue changes in patients.

The neural basis of constraint-induced movement therapy.

PURPOSE OF REVIEW: This review describes our current understanding of the changes in brain function and structure that occur in response to an intensive form of motor rehabilitation, constraint-induced movement therapy (CIMT), that has been shown to be efficacious in promoting motor function of the paretic upper limb of stroke patients. RECENT FINDINGS: Studies using transcranial magnetic stimulation have demonstrated consistently an increase in the size of the representation of paretic hand muscles in the ipsilesional motor cortex after CIMT. This motor map expansion occurs in response to CIMT delivered at all time periods after stroke, from within days to after several years. Functional neuroimaging studies have shown varying patterns of change in activation within the sensorimotor network after CIMT. This variability may depend on the extent of stroke-induced damage to the corticospinal tract, the major descending motor pathway in the brain. This variability may also stem from interacting plastic changes in brain structure occurring in response to CIMT. SUMMARY: CIMT is the first well defined poststroke motor rehabilitation to have identified changes in brain function and structure that accompany gains in motor function of the paretic upper limb. However, a causal link between observed changes in brain function/structure and motor gains due to CIMT has not yet been established. There is still much work to be done to understand the relationship between changes in brain function/structure and gains in motor function. Such studies should employ rigorous experimental controls to enable strong conclusions to be drawn regarding the neural effects of CIMT and how those effects confer behavioral efficacy of the therapy.

Microstructural status of ipsilesional and contralesional corticospinal tract correlates with motor skill in chronic stroke patients.

Greater loss in structural integrity of the ipsilesional corticospinal tract (CST) is associated with poorer motor outcome in patients with hemiparetic stroke. Animal models of stroke have demonstrated that structural remodeling of white matter in the ipsilesional and contralesional hemispheres is associated with improved motor recovery. Accordingly, motor recovery in patients with stroke may relate to the relative strength of CST degeneration and remodeling. This study examined the relationship between microstructural status of brain white matter tracts, indexed by the fractional anisotropy (FA) metric derived from diffusion tensor imaging (DTI) data, and motor skill of the stroke-affected hand in patients with chronic stroke. Voxelwise analysis revealed that motor skill significantly and positively correlated with FA of the ipsilesional and contralesional CST in the patients. Additional voxelwise analyses showed that patients with poorer motor skill had reduced FA of bilateral CST compared to normal control subjects, whereas patients with better motor skill had elevated FA of bilateral CST compared to controls. These findings were confirmed using a DTI-tractography method applied to the CST in both hemispheres. The results of this study suggest that the level of motor skill recovery achieved in patients with hemiparetic stroke relates to microstructural status of the CST in both the ipsilesional and contralesional hemispheres, which may reflect the net effect of degeneration and remodeling of bilateral CST.

Enhanced cortical activation in the contralesional hemisphere of chronic stroke patients in response to motor skill challenge.

The brain processes involved in the restoration of motor skill after hemiparetic stroke are not fully understood. The current study compared cortical activity in chronic stroke patients who successfully recovered hand motor skill and normal control subjects during performance of kinematically matched unskilled and skilled hand movements using functional magnetic resonance imaging. We found that cortical activation during performance of the unskilled movement was increased in the patients relative to controls in the contralesional primary sensorimotor cortex. Performance of the skilled movement elicited increased activation in the patients relative to controls in the contralesional primary sensorimotor cortex, ventral premotor cortex, supplementary motor area/cingulate, and occipitoparietal cortex. Further, the activation change in the contralesional occipitoparietal cortex was greater in the patients relative to controls with the increase in motor skill challenge. Kinematic differences, mirror movements, and residual motor deficits did not account for the enhanced activation in the contralesional cortices in the patients. These results suggest that activation in the contralesional cortical network was enhanced as a function of motor skill challenge in stroke patients with good motor recovery. The findings of the current study suggest that successful recovery of motor skill after hemiparetic stroke involves participation of the contralesional cortical network.

Structural and functional plasticity in the somatosensory cortex of chronic stroke patients.

Animal studies have demonstrated that motor recovery after hemiparetic stroke is associated with functional and structural brain plasticity. While studies in stroke patients have revealed functional plasticity in sensorimotor cortical areas in association with motor recovery, corresponding structural plasticity has not been shown. We sought to test the hypothesis that chronic hemiparetic stroke patients exhibit structural plasticity in the same sensorimotor cortical areas that exhibit functional plasticity. Functional MRI during unilateral tactile stimulation and structural MRI was conducted in chronic stroke patients and normal subjects. Using recently developed computational methods for high-resolution analysis of MRI data, we evaluated for between-group differences in functional activation responses, and cortical thickness of areas that showed an enhanced activation response in the patients. We found a significant (P < 0.005) increase in the activation response in areas of the ventral postcentral gyrus (POG) in the patients relative to controls. These same ventral POG areas showed a significant (P < 0.05) increase in cortical thickness in the patients. Control cortical areas did not show a significant between-group difference in thickness or activation response. These results provide the first evidence of structural plasticity co-localized with areas exhibiting functional plasticity in the human brain after stroke.

Correlated change in upper limb function and motor cortex activation after verum and sham acupuncture in patients with chronic stroke.

BACKGROUND: Acupuncture may improve motor function in patients with chronic hemiparetic stroke, yet the neural mechanisms underlying such an effect are unknown. As part of a sham-controlled, randomized clinical trial testing the efficacy of a 10-week acupuncture protocol in patients with chronic hemiparetic stroke, we examined the relationship between changes in function of the affected upper limb and brain activation using functional magnetic resonance imaging (fMRI). METHODS: Seven (7) chronic hemiparetic stroke patients underwent fMRI and testing of function of the affected upper limb (spasticity and range-of-motion) before and after a 10-week period of verum (N=4) or sham (N=3) acupuncture. The correlation between changes in function of the affected upper limb and brain activation after treatment was tested across patients. RESULTS: We found a significant positive correlation between changes in function of the affected upper limb (spasticity and range of motion) and activation in a region of the ipsilesional motor cortex. Patients treated with verum acupuncture showed a trend toward a greater maximum activation change in this motor cortical area as compared to those treated with sham acupuncture. CONCLUSIONS: Acupuncture may improve function of the affected upper limb in chronic hemiparetic stroke patients by increasing activity in the ipsilesional motor cortex.

Motor rehabilitation and brain plasticity after hemiparetic stroke.

This review intends to begin to build a bridge between our understanding of the effect of motor rehabilitation and brain plasticity on recovery after hemiparetic stroke. It discusses the impact of intensive post-stroke motor rehabilitation on motor recovery. This is followed by an overview of our current understanding, based on human brain mapping technologies, of brain plasticity underlying spontaneous recovery after hemiparetic stroke. These discussions lead to a descriptive review of human brain mapping studies that have begun to provide an understanding of the neural basis of rehabilitation-induced gains in motor function after stroke. Finally, it speculates on how a solid understanding of the neural underpinnings of spontaneous and rehabilitation-induced motor recovery will permit brain mapping technologies to be applied toward optimizing post-stroke motor rehabilitation.

Comparing prognostic strength of acute corticospinal tract injury measured by a new diffusion tensor imaging based template approach versus common approaches.

BACKGROUND: Long-term motor outcome of acute stroke patients with severe motor impairment is difficult to predict. While measure of corticospinal tract (CST) injury based on diffusion tensor imaging (DTI) in subacute stroke patients strongly predicts motor outcome, its predictive value in acute stroke patients is unclear. Using a new DTI-based, density-weighted CST template approach, we demonstrated recently that CST injury measured in acute stroke patients with moderately-severe to severe motor impairment of the upper limb strongly predicts motor outcome of the limb at 6 months. NEW METHOD: The current study compared the prognostic strength of CST injury measured in 10 acute stroke patients with moderately-severe to severe motor impairment of the upper limb by the new density-weighted CST template approach versus several variants of commonly used DTI-based approaches. RESULTS AND COMPARISON WITH EXISTING METHODS: Use of the density-weighted CST template approach yielded measurements of acute CST injury that correlated most strongly, in absolute magnitude, with 6-month upper limb strength (rs=0.93), grip (rs=0.94) and dexterity (rs=0.89) compared to all other 11 approaches. Formal statistical comparison of correlation coefficients revealed that acute CST injury measured by the density-weighted CST template approach correlated significantly more strongly with 6-month upper limb strength, grip and dexterity than 9, 10 and 6 of the 11 alternative measurements, respectively. CONCLUSIONS: Measurements of CST injury in acute stroke patients with substantial motor impairment by the density-weighted CST template approach may have clinical utility for anticipating healthcare needs and improving clinical trial design.

Motor recovery and cortical reorganization after constraint-induced movement therapy in stroke patients: a preliminary study.

Constraint-induced movement therapy (CIMT) is a physical rehabilitation regime that has been previously shown to improve motor function in chronic hemiparetic stroke patients. However, the neural mechanisms supporting rehabilitation-induced motor recovery are poorly understood. The goal of this study was to assess motor cortical reorganization after CIMT using functional magnetic resonance imaging (fMRI). In a repeated-measures design, 4 incompletely recovered chronic stroke patients treated with CIMT underwent motor function testing and fMRI. Five age-matched normal subjects were also imaged. A laterality index (LI) was determined from the fMRI data, reflecting the distribution of activation in motor cortices contralateral compared with ipsilateral to the moving hand. Pre-intervention fMRI showed a lower LI during affected hand movement of stroke patients (LI = 0.23+/-0.07) compared to controls (LI unaffected patient hand = 0.65+/-0.10; LI dominant normal hand = 0.65+/-0.11; LI nondominant normal hand = 0.69+/-0.11; P < 0.05) due to trends toward increased ipsilateral motor cortical activation. Motor function testing showed that patients made significant gains in functional use of the stroke-affected upper extremity (detected by the Motor Activity Log) and significant reductions in motor impairment (detected by the Fugl-Meyer Stroke Scale and the Wolf Motor Function Test) immediately after CIMT, and these effects persisted at 6-month follow-up. The behavioral effects of CIMT were associated with a trend toward a reduced LI from pre-intervention to immediately post-intervention (LI = -0.01+/-0.06, P = 0.077) and 6 months post-intervention (LI = -0.03+/-0.15). Stroke-affected hand movement was not accompanied by mirror movements during fMRI, and electromyographic measures of mirror recruitment under simulated fMRI conditions were not correlated with LI values. These data provide preliminary evidence that gains in motor function produced by CIMT in chronic stroke patients may be associated with a shift in laterality of motor cortical activation toward the undamaged hemisphere.

Corticospinal tract diffusion abnormalities early after stroke predict motor outcome.

BACKGROUND: Prognosis of long-term motor outcome of acute stroke patients with severe motor impairment is difficult to determine. OBJECTIVE: Our primary goal was to evaluate the prognostic value of corticospinal tract (CST) injury on motor outcome of the upper limb compared with motor impairment level and lesion volume. METHODS: In all, 10 acute stroke patients with moderately severe to severe motor impairment of the upper limb underwent diffusion tensor imaging (DTI) and testing of upper limb strength and dexterity at acute, subacute, and chronic poststroke time points. A density-weighted CST atlas was constructed using DTI tractography data from normal participants. This CST atlas was applied, using a largely automated process, to DTI data from patients to quantify CST injury at each time point. Differences in axial diffusivity (AD), radial diffusivity (RD), and fractional anisotropy (FA) of the ipsilesional CST relative to the contralesional CST were measured. RESULTS: Acute loss in CST AD correlated most strongly and significantly with subacute and chronic strength and dexterity and remained significant after adjusting for acute motor impairment or lesion volume. Subacute loss in CST FA correlated most strongly with chronic dexterity, whereas subacute behavioral measures of limb strength correlated most strongly with chronic strength measures. CONCLUSIONS: Loss in acute CST AD and subacute CST FA are strong prognostic indicators of future motor functions of the upper limb for stroke patients with substantial initial motor impairment. DTI-derived measure of CST injury early after stroke may have utility in health care planning and in design of acute stroke clinical trials.

Increase in sensorimotor cortex response to somatosensory stimulation over subacute poststroke period correlates with motor recovery in hemiparetic patients.

BACKGROUND: . Somatosensory input to the motor cortex may play a critical role in motor relearning after hemiparetic stroke. OBJECTIVE: . The authors tested the hypothesis that motor recovery after hemiparetic stroke relates to changes in responsiveness of the sensorimotor cortex (SMC) to somatosensory input. METHODS: . A total of 10 hemiparetic stroke patients underwent serial functional magnetic resonance imaging (fMRI) during tactile stimulation and testing of sensorimotor function over 1 year-at early subacute, late subacute, and chronic poststroke time points. RESULTS: . Over the subacute poststroke period, increased responsiveness of the ipsilesional SMC to tactile stimulation of a stroke-affected digit correlated strongly with concurrent gains in motor function. Increased responsiveness of the ipsilesional and contralesional SMC over the subacute period also correlated strongly with motor recovery experienced over the first year poststroke. CONCLUSIONS: . These findings suggest that increased responsiveness of the SMC to somatosensory stimulation over the subacute poststroke period may contribute to motor recovery.

Predicting efficacy of robot-aided rehabilitation in chronic stroke patients using an MRI-compatible robotic device.

We are investigating the neural correlates of motor recovery promoted by robot-mediated therapy in chronic stroke. This pilot study asked whether efficacy of robot-aided motor rehabilitation in chronic stroke could be predicted by a change in functional connectivity within the sensorimotor network in response to a bout of motor rehabilitation. To address this question, two stroke patients participated in a functional connectivity MRI study pre and post a 12-week robot-aided motor rehabilitation program. Functional connectivity was evaluated during three consecutive scans before the rehabilitation program: resting-state; point-to-point reaching movements executed by the paretic upper extremity (UE) using a newly developed MRI-compatible sensorized passive manipulandum; resting-state. A single resting-state scan was conducted after the rehabilitation program. Before the program, UE movement reduced functional connectivity between the ipsilesional and contralesional primary motor cortex. Reduced interhemispheric functional connectivity persisted during the second resting-state scan relative to the first and during the resting-state scan after the rehabilitation program. Greater reduction in interhemispheric functional connectivity during the resting-state was associated with greater gains in UE motor function induced by the 12-week robotic therapy program. These findings suggest that greater reduction in interhemispheric functional connectivity in response to a bout of motor rehabilitation may predict greater efficacy of the full rehabilitation program.

Structural damage to the corticospinal tract correlates with bilateral sensorimotor cortex reorganization in stroke patients.

Damage to the corticospinal tract (CST) in stroke patients has been associated with functional reorganization in the ipsilesional and contralesional sensorimotor cortices. However, it is unknown whether a quantitative relationship exists between the extent of structural damage to the CST and functional reorganization in stroke patients. The purpose of the current study was to examine the relationship between structural CST damage and motor task-related cortical activity in chronic hemiparetic stroke patients. In 10 chronic hemiparetic stroke patients with heterogeneous lesions, CST damage was quantified using conventional structural magnetic resonance imaging and tractography based on diffusion tensor imaging. Cortical activity was measured using functional magnetic resonance imaging during repetitive flexion/extension movements of the digits. We found that the two measures of CST damage were strongly correlated. Moreover, greater CST damage was significantly and linearly correlated with increased activation during affected hand movement in the hand area of the contralesional primary sensorimotor cortex (M1/S1) and in the ipsilesional M1/S1 ventral to the hand area. To our knowledge, this is the first demonstration of a quantitative relationship between the extent of structural damage to the CST and functional reorganization in stroke patients. This relationship was observed in stroke patients with heterogeneous lesions, suggesting that CST damage is a factor relevant to the variation in functional reorganization in the clinical population.

Finger motion sensors for fMRI motor studies.

The kinematics of motor task performance affect brain activity. However, few functional magnetic resonance imaging (fMRI) motor studies have accounted for on-line kinematics because there are currently few MRI-compatible devices to record motor performance. We built a device based on Micro-Electro-Mechanical System (MEMS) gyroscopes that measures the angular velocity of one segment of each of the 10 fingers while a subject performs a finger motor task during fMRI. Finger position, acceleration, and jerk were computed from the angular velocity measurements. The signal-to-noise ratio (SNR) of the MEMS sensors (range: 27.10-34.36 dB) allowed for clear detection of velocity of finger motion during fMRI motor task performance, and showed good stability over time. We demonstrate that use of the MEMS-based device, while negligibly increasing radiofrequency (RF) noise in the scanning environment, did not cause MR image artifacts nor alter fMRI statistical activation maps. Further, we show that signal from the MEMS sensors was not affected by the high static magnetic field (3 T). Increasing the RF power transmitted during fMRI by using a body coil, as compared to a head coil, decreased the sensor's SNR from 30.7 to 24.2 dB, though this loss in SNR did not interfere with the ability to measure velocity of finger motion. We demonstrate the utility of the MEMS-based device in fMRI motor studies through two experiments that examined the relationship between finger movement kinematics and fMRI activation in the healthy and injured brain. On-line acquisition of motor performance during fMRI, through the use of the MEMS-based device, promises to allow for a more detailed understanding of the relationship between movement kinematics and activation in the healthy and injured brain.

Acupuncture for upper-extremity rehabilitation in chronic stroke: a randomized sham-controlled study.

OBJECTIVE: To compare the effects of traditional Chinese acupuncture with sham acupuncture on upper-extremity (UE) function and quality of life (QOL) in patients with chronic hemiparesis from stroke. DESIGN: A prospective, sham-controlled, randomized controlled trial (RCT). SETTING: Patients recruited through a hospital stroke rehabilitation program. PARTICIPANTS: Thirty-three subjects who incurred a stroke 0.8 to 24 years previously and had moderate to severe UE functional impairment. INTERVENTIONS: Active acupuncture tailored to traditional Chinese medicine diagnoses, including electroacupuncture, or sham acupuncture. Up to 20 treatment sessions (mean, 16.9) over a mean of 10.5 weeks. MAIN OUTCOME MEASURES: UE motor function, spasticity, grip strength, range of motion (ROM), activities of daily living, QOL, and mood. All outcomes were measured at baseline and after treatment. RESULTS: Intention-to-treat (ITT) analyses found no statistically significant differences in outcomes between active and sham acupuncture groups. Analyses of protocol-compliant subjects revealed significant improvement in wrist spasticity (P<.01) and both wrist (P<.01) and shoulder (P<.01) ROM in the active acupuncture group, and improvement trends in UE motor function (P=.09) and digit ROM (P=.06). CONCLUSIONS: Based on ITT analyses, we conclude that acupuncture does not improve UE function or QOL in patients with chronic stroke symptoms. However, gains in UE function observed in protocol-compliant subjects suggest traditional Chinese acupuncture may help patients with chronic stroke symptoms. These results must be interpreted cautiously because of small sample sizes and multiple, unadjusted, post hoc comparisons. A larger, more definitive RCT using a similar design is feasible and warranted.

Motor cortex activation is related to force of squeezing.

Primate studies have demonstrated that motor cortex neurons show increased activity with increased force of movement. In humans, this relationship has received little study during a power grip such as squeezing, and has previously only been evaluated across a narrow range of forces. Functional MRI was performed in eight healthy subjects who alternated between rest and right hand squeezing at one of three force levels. During scanning, motor performances were recorded using a dynamometer. At each force level, activation volume was measured within left sensorimotor cortex, right sensorimotor cortex, and a midline supplementary motor area. In left sensorimotor cortex, % signal change was also assessed. The range of force generated across the three force levels varied from 4.9 N to 276 N. In left sensorimotor cortex, activation volume increased significantly with greater force. The % signal change also increased with greater force and correlated closely with activation volume. In supplementary motor area, activation volume increased significantly with increasing force, but with greater intersubject variability. In right sensorimotor cortex, a trend for larger activation volumes with greater force did not reach significance. The laterality index, an expression of the relative degree of contralateral vs. ipsilateral sensorimotor cortex activation, did not change across the three force levels. Increased force of squeezing is associated with increased contralateral sensorimotor cortex and supplementary motor area activation. This relationship was found across the full spectrum of forces that the human hand is capable of generating. Use of a valid, reliable method for assessing motor behavior during functional MRI may be important to clinical applications.