Background
Diseases induced by metabolic disorders, eg, Type 2 diabetes, has recently been linked to both sensory and motor deficit in the absence of a formal clinical diagnosis of peripheral ...neuropathy. Studies have demonstrated mild cognitive impairment in diabetic patients, which also plays a role in one's loss of ability to successfully perform basic motor activities. This project focused on evaluating cognitive function while maintaining balance. We hypothesized that simultaneous cognitive and motor deficit would occur among adults with Type 2 diabetes versus healthy age‐ and sex‐matched control during a balance task.
Methods
A sample of 10 Type 2 diabetes patients and 10 age‐matched and sex‐matched controls underwent a series of sensory, motor, cognitive, and cognitive‐motor evaluations. Blood pressure and A1c levels were assessed.
Results
Significantly lower cognitive function scores, particularly in the domain of working memory, were exhibited in the diabetic group than controls. Balance in the diabetic group was overall poorer in both single‐ and dual‐tasks than controls. When diabetic patients were asked to verbally recall different words while maintaining their balance, their accuracy rate was significantly lower than controls. Some health state measures were found to co‐vary with motor function. Increased body mass index in the diabetic group did not account for motor function deficit.
Significance
Our data suggest that: (1) systemic deficit beyond tactile dysfunction and increased body mass index contribute to reduced motor function in diabetes, and (2) both balance and working memory functions are simultaneously impaired in patients with Type 2 diabetes.
This study aimed to explore correlations between spasticity and motor impairments in the upper and lower limbs (UL and LL) in ambulatory chronic stroke survivors.
We performed clinical assessments in ...28 ambulatory chronic stroke survivors with spastic hemiplegia (female:12; male: 16; mean ages = 57.8 ± 11.8 yr; 76 ± 45 months after stroke).
In the upper limb, spasticity index (SI_UL) and Fugl-Meyer Motor Assessment (FMA_UL) showed a significant correlation. SI_UL showed a significant negative correlation with handgrip strength of the affected side (r = -0.4, p = 0.035) while FMA_UL had a significant positive correlation (r = 0.77, p < 0.001). In the LL, no correlation was found between SI_LL and FMA_LL. There was a significant and high correlation between timed up and go test (TUG) and gait speed (r = 0.93, p < 0.001). Gait speed was positively correlated with SI_LL (r = 0.48, p = 0.01), and negatively correlated with FMA_LL (r = -0.57, p = 0.002). Age and time since stroke showed no association in analyses for both UL and LL.
Spasticity has a negative correlation on motor impairment in the upper limb but not in the lower limb. Motor impairment was significantly correlated with grip strength in the upper limb and gait performance in the lower limb of ambulatory stroke survivors.
Acute intermittent hypoxia (AIH) is an emerging technique for facilitating neural plasticity in individuals with chronic incomplete spinal cord injury (iSCI). A single sequence of AIH enhances hand ...grip strength and ankle plantarflexion torque, but underlying mechanisms are not yet clear. We sought to examine how AIH-induced changes in magnitude and spatial distribution of the electromyogram (EMG) of the biceps and triceps brachii contributes to improved strength. Seven individuals with iSCI visited the laboratory on two occasions, and received either AIH or Sham AIH intervention in a randomized order. AIH consisted of 15 brief (∼60s) periods of low oxygen (fraction of inspired O2 = 0.09) alternating with 60s of normoxia, whereas Sham AIH consisted of repeated exposures to normoxic air. High-density surface EMG of biceps and triceps brachii was recorded during maximal elbow flexion and extension. We then generated spatial maps which distinguished active muscle regions prior to and 60 min after AIH or Sham AIH. After an AIH sequence, elbow flexion and extension forces increased by 91.7 ± 88.4% and 51.7 ± 57.8% from baseline, respectively, whereas there was no difference after Sham AIH. Changes in strength were associated with an altered spatial distribution of EMG and increased root mean squared EMG amplitude in both biceps and triceps brachii muscles. These data suggest that altered motor unit activation profiles may underlie improved volitional strength after a single dose of AIH and warrant further investigation using single motor unit analysis techniques to further elucidate mechanisms of AIH-induced plasticity.
•Acute intermittent hypoxia (AIH) is an emerging therapeutic intervention for people with incomplete spinal cord injury (SCI).•Effects of AIH on respiratory motor function are well-studied, but the effects on limb function are not.•Here we show that AIH enhances elbow flexion and extension strength in persons with SCI at the cervical level.•AIH-induced improvements in strength were accompanied by an increase in the magnitude and area of muscle activity.
Many stroke patients suffer from the drop foot syndrome, which is characterized by a limited ability to lift the foot and leads to a pathological gait. We consider treatment of this syndrome via ...Functional Electrical Stimulation (FES) of the peroneal nerve during the swing phase of the paretic foot. We highlight the role of feedback control for addressing the challenges that result from the large individuality and time-variance of muscle response dynamics. Unlike many previous approaches, we do not reduce the control problem to the scalar case. Instead, the entire pitch angle trajectory of the paretic foot is measured by means of a 6D Inertial Measurement Unit (IMU) and controlled by an Iterative Learning Control (ILC) scheme for variable-pass-length systems. While previously suggested controllers were often validated for the strongly simplified case of sitting or lying subjects, we demonstrate the effectiveness of the proposed approach in experimental trials with walking drop foot patients. Our results reveal that conventional trapezoidal stimulation intensity profiles may produce a safe foot lift, but often at the cost of too high intensities and an unphysiological foot pitch motion. Starting from such conservative intensity profiles, the proposed learning controller automatically achieves a desired foot motion within one or two strides and keeps adjusting the stimulation to compensate time-variant muscle dynamics and disturbances.
•Carbamazepine (CBZ)-levetiracetam (LEV) adjuvant treatment impaired motor coordination than individual drug treatment.•Chronic CBZ-LEV adjunctive treatment induced cortico-cerebellar toxicity by ...decimating antioxidative enzymatic activities.•Prolonged CBZ-LEV adjunctive treatment induced neuroinflammation and lipid peroxidation than individual drug.•There was evidence of cortical and cerebellar morphological alterations following CBZ-LEV adjunctive treatment.
This study examined the effects of carbamazepine (CBZ) or levetiracetam (LEV) and sub-therapeutic doses of the combination of the two conventional antiepileptics on some of the markers of motor coordination.
Twenty-four male Wistar rats (140 ± 5 g) were randomized into 4 groups (n = 6). Group I rats received physiological saline (0.2 ml), group II were administered CBZ (25.0 mg/kg), group III received LEV (50 mg/kg), while group IV rats were given sub-therapeutic doses of CBZ (12.5 mg/kg) and LEV (25 mg/kg) intraperitoneally for 28 days. Thereafter the animals were subjected to behavioral and biochemical investigations, while the frontal lobe and cerebellar tissue were preserved for histological investigation. Data were subjected to descriptive and inferential statistics, and the results presented as mean ± SEM, analyzed using one-way Analysis of variance (ANOVA) and Student- Newman Keuls post hoc analysis where appropriate. p < 0.05 was considered statistically significant.
There was significant alteration in fine and skilled movement after the CBZ, and CBZ + LEV chronic treatment compared with the control. The CBZ, and CBZ + LEV combination treatment increased the frontal lobe and cerebellar activities of acetylcholinesterase, malondialdehyde concentration, tissue necrotic factor alpha and decreased the activities of super oxide dismutase relative to the control. Disorganization of the histoarchitecture of the frontal lobe and cerebellum was characterized by cellular atrophy, chromatolysis and hyalinization.
Chronic CBZ, and CBZ + LEV combination treatment produced psychomotor dysfunction and neurotoxicity in this order CBZ + LEV > CBZ > LEV in the rats.
Individuals with severe motor impairments often require alternative means to access computers and communication technology. A range of alternative access devices exist; however, most rely on use of a ...single access modality. While this approach works for some individuals, it can be limiting for others. This study explored the use of a multi-modal prototype (eye-tracking + switch-scanning) on typing performance with a range of individuals with motor impairments. The multi-modal prototype was compared to eye-tracking alone for this study. Results indicated that the multi-modal prototype had significantly slower typing rate but significantly lower total errors compared to eye-tracking alone. Analysis of individual data revealed four subgroups of clinical relevance including individuals that 1) benefit from multi-modal, 2) benefit from eye-tracking, 3) demonstrate learning and 4) demonstrate fluctuating performance.
•There was no alteration in BDNF expression levels in the cortex after ICH.•ICH shifted the interhemispheric balance of cortical BDNF expression.•Ipsilateral cortical BDNF positively correlated with ...motor function after ICH.
Intracerebral hemorrhage (ICH) is a subtype of stroke that causes major motor impairments. Brain-derived neurotrophic factor (BDNF) is known to have important roles in neuroplasticity and beneficially contributes to stroke recovery. This study aimed to characterize BDNF expression in the motor cortex after ICH and investigate the relationship between cortical BDNF expression and behavioral outcomes using an ICH rat model. Wistar rats were divided into two groups: a SHAM group (n = 7) and an ICH group (n = 8). ICH was induced by the injection of collagenase into the left striatum near the internal capsule. For behavioral assessments, the cylinder test and open field test were performed before surgery and 3 days, 1 week, 2 weeks, and 4 weeks after surgery. Following the behavioral assessments at 4 weeks, BDNF expression in the ipsilateral and contralateral motor cortex was assayed using RT-PCR and ELISA methods. There was no significant difference in either cortical BDNF mRNA or protein expression levels between the SHAM and ICH groups. However, the asymmetry index of BDNF mRNA expression between the ipsilateral and contralateral hemispheres shifted to the ipsilateral hemisphere after ICH. Furthermore, the ipsilateral cortical BDNF mRNA expression level positively correlated with motor function in the affected forelimb after ICH. This study describes for the first time that cortical BDNF mRNA expression is related to post-ICH motor impairment. These results highlight the importance of assessing the interhemispheric laterality of BDNF expression and could help develop novel treatment strategies for BDNF-dependent recovery after ICH.
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