The changes of neuroactivity of Tui Na (Chinese massage) at Hegu acupoint on sensorimotor cortex in stroke patients with upper limb motor dysfunction: a fNIRS study

BACKGROUND

Tui Na (Chinese massage) is a relatively simple, inexpensive, and non-invasive intervention, and has been used to treat stroke patients for many years in China. Tui Na acts on specific parts of the body which are called meridians and acupoints to achieve the role of treating diseases. Yet the underlying neural mechanism associated with Tui Na is not clear due to the lack of detection methods.

OBJECTIVE

Functional near-infrared spectroscopy (fNIRS) was used to explore the changes of sensorimotor cortical neural activity in patients with upper limb motor dysfunction of stroke and healthy control groups during Tui Na Hegu Point.

METHODS

Ten patients with unilateral upper limb motor dysfunction after stroke and eight healthy subjects received Tui Na. fNIRS was used to record the hemodynamic data in the sensorimotor cortex and the changes in blood flow were calculated based on oxygenated hemoglobin (Oxy-Hb), the task session involved repetitive Tui Na on Hegu acupoint, using a block design [six cycles: rest (20 seconds); Tui Na (20 seconds); rest (30 seconds)]. The changes in neural activity in sensorimotor cortex could be inferred according to the principle of neurovascular coupling, and the number of activated channels in the bilateral hemisphere was used to calculate the lateralization index.

RESULT

1. For hemodynamic response induced by Hegu acupoint Tui Na, a dominant increase in the contralesional primary sensorimotor cortex during Hegu point Tui Na of the less affected arm in stroke patients was observed, as well as that in healthy controls, while this contralateral pattern was absent during Hegu point Tui Na of the affected arm in stroke patients. 2. Concerning the lateralization index in stroke patients, a significant difference was observed between lateralization index values for the affected arm and the less affected arm (P < 0.05). Wilcoxon tests showed a significant difference between lateralization index values for the affected arm in stroke patients and lateralization index values for the dominant upper limb in healthy controls (P < 0.05), and no significant difference between lateralization index values for the less affected arm in stroke patients and that in healthy controls (P = 0.36).

CONCLUSION

The combination of Tui Na and fNIRS has the potential to reflect the functional status of sensorimotor neural circuits. The changes of neuroactivity in the sensorimotor cortex when Tui Na Hegu acupoint indicate that there is a certain correlation between acupoints in traditional Chinese medicine and neural circuits.

Virtual reality and motor imagery for early post-stroke rehabilitation

BACKGROUND

Motor impairment is a common consequence of stroke causing difficulty in independent movement. The first month of post-stroke rehabilitation is the most effective period for recovery. Movement imagination, known as motor imagery, in combination with virtual reality may provide a way for stroke patients with severe motor disabilities to begin rehabilitation.

METHODS

The aim of this study is to verify whether motor imagery and virtual reality help to activate stroke patients' motor cortex. 16 acute/subacute (< 6 months) stroke patients participated in this study. All participants performed motor imagery of basketball shooting which involved the following tasks: listening to audio instruction only, watching a basketball shooting animation in 3D with audio, and also performing motor imagery afterwards. Electroencephalogram (EEG) was recorded for analysis of motor-related features of the brain such as power spectral analysis in the [Formula: see text] and [Formula: see text] frequency bands and spectral entropy. 18 EEG channels over the motor cortex were used for all stroke patients.

RESULTS

All results are normalised relative to all tasks for each participant. The power spectral densities peak near the [Formula: see text] band for all participants and also the [Formula: see text] band for some participants. Tasks with instructions during motor imagery generally show greater power spectral peaks. The p-values of the Wilcoxon signed-rank test for band power comparison from the 18 EEG channels between different pairs of tasks show a 0.01 significance of rejecting the band powers being the same for most tasks done by stroke subjects. The motor cortex of most stroke patients is more active when virtual reality is involved during motor imagery as indicated by their respective scalp maps of band power and spectral entropy.

CONCLUSION

The resulting activation of stroke patient's motor cortices in this study reveals evidence that it is induced by imagination of movement and virtual reality supports motor imagery. The framework of the current study also provides an efficient way to investigate motor imagery and virtual reality during post-stroke rehabilitation.

Deficiency in Androgen Receptor Aggravates Traumatic Brain Injury-Induced Pathophysiology and Motor Deficits in Mice

Androgens have been shown to have a beneficial effect on brain injury and lower reactive astrocyte expression after TBI. Androgen receptors (ARs) are known to mediate the neuroprotective effects of androgens. However, whether ARs play a crucial role in TBI remains unknown. In this study, we investigated the role of ARs in TBI pathophysiology, using AR knockout (ARKO) mice. We used the controlled cortical impact model to produce primary and mechanical brain injuries and assessed motor function and brain-lesion volume. In addition, the AR knockout effects on necrosis and autophagy were evaluated after TBI. AR knockout significantly increased TBI-induced expression of the necrosis marker alpha-II-spectrin breakdown product 150 and astrogliosis marker glial fibrillary acidic protein. In addition, the TBI-induced astrogliosis increase in ARKO mice lasted for three weeks after a TBI. The autophagy marker Beclin-1 was also enhanced in ARKO mice compared with wild-type mice after TBI. Our results also indicated that ARKO mice showed a more unsatisfactory performance than wild-type mice in a motor function test following TBI. Further, they were observed to have more severe lesions than wild-type mice after injury. These findings strongly suggest that ARs play a role in TBI.

Glutamate, Glutamine, GABA and Oxidative Products in the Pons Following Cortical Injury and Their Role in Motor Functional Recovery

Brain injury leads to an excitatory phase followed by an inhibitory phase in the brain. The clinical sequelae caused by cerebral injury seem to be a response to remote functional inhibition of cerebral nuclei located far from the motor cortex but anatomically related to the injury site. It appears that such functional inhibition is mediated by an increase in lipid peroxidation (LP). To test this hypothesis, we report data from 80 rats that were allocated to the following groups: the sham group (n = 40), in which rats received an intracortical infusion of artificial cerebrospinal fluid (CSF); the injury group (n = 20), in which rats received CSF containing ferrous chloride (FeCl₂, 50 mM); and the recovery group (n = 20), in which rats were injured and allowed to recover. Beam-walking, sensorimotor and spontaneous motor activity tests were performed to evaluate motor performance after injury. Lipid fluorescent products (LFPs) were measured in the pons. The total pontine contents of glutamate (GLU), glutamine (GLN) and gamma-aminobutyric acid (GABA) were also measured. In injured rats, the motor deficits, LFPs and total GABA and GLN contents in the pons were increased, while the GLU level was decreased. In contrast, in recovering rats, none of the studied variables were significantly different from those in sham rats. Thus, motor impairment after cortical injury seems to be mediated by an inhibitory pontine response, and functional recovery may result from a pontine restoration of the GLN-GLU-GABA cycle, while LP may be a primary mechanism leading to remote pontine inhibition after cortical injury.

A Network of Psychopathological, Cognitive, and Motor Symptoms in Schizophrenia Spectrum Disorders

Schizophrenia spectrum disorders (SSDs) are complex syndromes involving psychopathological, cognitive, and also motor symptoms as core features. A better understanding of how these symptoms mutually impact each other could translate into diagnostic, prognostic, and, eventually, treatment advancements. The present study aimed to: (1) estimate a network model of psychopathological, cognitive, and motor symptoms in SSD; (2) detect communities and explore the connectivity and relative importance of variables within the network; and (3) explore differences in subsample networks according to remission status. A sample of 1007 patients from a multisite cohort study was included in the analysis. We estimated a network of 43 nodes, including all the items from the Positive and Negative Syndrome Scale, a cognitive assessment battery and clinical ratings of extrapyramidal symptoms. Methodologies specific to network analysis were employed to address the study's aims. The estimated network for the total sample was densely interconnected and organized into 7 communities. Nodes related to insight, abstraction capacity, attention, and suspiciousness were the main bridges between network communities. The estimated network for the subgroup of patients in remission showed a sparser density and a different structure compared to the network of nonremitted patients. In conclusion, the present study conveys a detailed characterization of the interrelations between a set of core clinical elements of SSD. These results provide potential novel clues for clinical assessment and intervention.

Impaired auditory discrimination and auditory-motor integration in hyperfunctional voice disorders

Hyperfunctional voice disorders (HVDs) are the most common class of voice disorders, consisting of diagnoses such as vocal fold nodules and muscle tension dysphonia. These speech production disorders result in effort, fatigue, pain, and even complete loss of voice. The mechanisms underlying HVDs are largely unknown. Here, the auditory-motor control of voice fundamental frequency (f_o) was examined in 62 speakers with and 62 speakers without HVDs. Due to the high prevalence of HVDs in singers, and the known impacts of singing experience on auditory-motor function, groups were matched for singing experience. Speakers completed three tasks, yielding: (1) auditory discrimination of voice f_o; (2) reflexive responses to sudden f_o shifts; and (3) adaptive responses to sustained f_o shifts. Compared to controls, and regardless of singing experience, individuals with HVDs showed: (1) worse auditory discrimination; (2) comparable reflexive responses; and (3) a greater frequency of atypical adaptive responses. Atypical adaptive responses were associated with poorer auditory discrimination, directly implicating auditory function in this motor disorder. These findings motivate a paradigm shift for understanding development and treatment of HVDs.

Early decreases in cortical mid-gamma peaks coincide with the onset of motor deficits and precede exaggerated beta build-up in rat models for Parkinson's disease

Evidence suggests that exaggerated beta range local field potentials (LFP) in basal ganglia-thalamocortical circuits constitute an important biomarker for feedback for deep brain stimulation in Parkinson's disease patients, although the role of this phenomenon in triggering parkinsonian motor symptoms remains unclear. A useful model for probing the causal role of motor circuit LFP synchronization in motor dysfunction is the unilateral dopamine cell-lesioned rat, which shows dramatic motor deficits walking contralaterally to the lesion but can walk steadily ipsilaterally on a circular treadmill. Within hours after 6-OHDA injection, rats show marked deficits in ipsilateral walking with early loss of significant motor cortex (MCx) LFP peaks in the mid-gamma 41-45 Hz range in the lesioned hemisphere; both effects were reversed by dopamine agonist administration. Increases in MCx and substantia nigra pars reticulata (SNpr) coherence and LFP power in the 29-40 Hz range emerged more gradually over 7 days, although without further progression of walking deficits. Twice-daily chronic dopamine antagonist treatment induced rapid onset of catalepsy and also reduced MCx 41-45 Hz LFP activity at 1 h, with increases in MCx and SNpr 29-40 Hz power/coherence emerging over 7 days, as assessed during periods of walking before the morning treatments. Thus, increases in high beta power in these parkinsonian models emerge gradually and are not linearly correlated with motor deficits. Earlier changes in cortical circuits, reflected in the rapid decreases in MCx LFP mid-gamma LFP activity, may contribute to evolving plasticity supporting increased beta range synchronized activity in basal ganglia-thalamocortical circuits after loss of dopamine receptor stimulation.

Handwritten Geometrical Patterns in the Evaluation of Motor Symptoms in Psychotic Disorders

The analysis of handwriting has been used in several contexts. For example, handwriting has shown to be of value in the study of motor symptoms in neurological and mental disorders. In the present work, the geometric analysis of handwriting patterns is proposed as a tool to evaluate motor symptoms in psychotic disorders. Specifically, we have employed the lacunarity, a measure of the heterogeneity of a spatial structure. Forty-two patients with a psychotic disorder and 35 matched healthy controls participated in the study. Participants were asked to copy some patterns with a pen on a white paper. The results showed that lacunarity was significantly higher in handwritten patterns from patients than from controls. In addition, we found higher values of lacunarity in handwritten patterns from patients with severe motor symptoms in comparison with patients with mild or absent motor symptoms. Lacunarity of handwritten patterns was significantly correlated with clinical scores of rigidity. In conclusion we argue that the heterogeneity of handwritten patterns could be used as a simple and objective measure of motor symptoms.

Are early measured resting-state EEG parameters predictive for upper limb motor impairment six months poststroke?

OBJECTIVES

Investigate whether resting-state EEG parameters recorded early poststroke can predict upper extremity motor impairment reflected by the Fugl-Meyer motor score (FM-UE) after six months, and whether they have prognostic value in addition to FM-UE at baseline.

METHODS

Quantitative EEG parameters delta/alpha ratio (DAR), brain symmetry index (BSI) and directional BSI (BSIdir) were derived from 62-channel resting-state EEG recordings in 39 adults within three weeks after a first-ever ischemic hemispheric stroke. FM-UE scores were acquired within three weeks (FM-UE_baseline) and at 26 weeks poststroke (FM-UE_w26). Linear regression analyses were performed using a forward selection procedure to predict FM-UE_w26.

RESULTS

BSI calculated over the theta band (BSI_theta) (β = -0.40; p = 0.013) was the strongest EEG-based predictor regarding FM-UE_w26. BSI_theta (β = -0.27; p = 0.006) remained a significant predictor when added to a regression model including FM-UE_baseline, increasing explained variance from 61.5% to 68.1%.

CONCLUSION

Higher BSI_theta values, reflecting more power asymmetry over the hemispheres, predict more upper limb motor impairment six months after stroke. Moreover, BSI_theta shows additive prognostic value regarding FM-UE_w26 next to FM-UE_baseline scores, and thereby contains unique information regarding upper extremity motor recovery.

SIGNIFICANCE

To our knowledge, we are the first to show that resting-state EEG parameters can serve as prognostic biomarkers of stroke recovery, in addition to FM-UE_baseline scores.

Baseline Motor Impairment Predicts Transcranial Direct Current Stimulation Combined with Physical Therapy-Induced Improvement in Individuals with Chronic Stroke

Transcranial direct current stimulation (tDCS) can enhance the effect of conventional therapies in post-stroke neurorehabilitation. The ability to predict an individual's potential for tDCS-induced recovery may permit rehabilitation providers to make rational decisions about who will be a good candidate for tDCS therapy. We investigated the clinical and biological characteristics which might predict tDCS plus physical therapy effects on upper limb motor recovery in chronic stroke patients. A cohort of 80 chronic stroke individuals underwent ten to fifteen sessions of tDCS plus physical therapy. The sensorimotor function of the upper limb was assessed by means of the upper extremity section of the Fugl-Meyer scale (UE-FM), before and after treatment. A backward stepwise regression was used to assess the effect of age, sex, time since stroke, brain lesion side, and basal level of motor function on UE-FM improvement after treatment. Following the intervention, UE-FM significantly improved (p < 0.05), and the magnitude of the change was clinically important (mean 6.2 points, 95% CI: 5.2-7.4). The baseline level of UE-FM was the only significant predictor (R 2 = 0.90, F (1, 76) = 682.80, p < 0.001) of tDCS response. These findings may help to guide clinical decisions according to the profile of each patient. Future studies should investigate whether stroke severity affects the effectiveness of tDCS combined with physical therapy.

Precise Regulation of the Basal PKCγ Activity by DGKγ Is Crucial for Motor Coordination

Diacylglycerol kinase γ (DGKγ) is a lipid kinase to convert diacylglycerol (DG) to phosphatidic acid (PA) and indirectly regulates protein kinase C γ (PKCγ) activity. We previously reported that the basal PKCγ upregulation impairs cerebellar long-term depression (LTD) in the conventional DGKγ knockout (KO) mice. However, the precise mechanism in impaired cerebellar LTD by upregulated PKCγ has not been clearly understood. Therefore, we first produced Purkinje cell-specific DGKγ KO (tm1d) mice to investigate the specific function of DGKγ in Purkinje cells and confirmed that tm1d mice showed cerebellar motor dysfunction in the rotarod and beam tests, and the basal PKCγ upregulation but not PKCα in the cerebellum of tm1d mice. Then, the LTD-induced chemical stimulation, K-glu (50 mM KCl + 100 µM, did not induce phosphorylation of PKCα and dissociation of GluR2 and glutamate receptor interacting protein (GRIP) in the acute cerebellar slices of tm1d mice. Furthermore, treatment with the PKCγ inhibitor, scutellarin, rescued cerebellar LTD, with the phosphorylation of PKCα and the dissociation of GluR2 and GRIP. In addition, nonselective transient receptor potential cation channel type 3 (TRPC3) was negatively regulated by upregulated PKCγ. These results demonstrated that DGKγ contributes to cerebellar LTD by regulation of the basal PKCγ activity.

Development of SaraHome: A novel, well-accepted, technology-based assessment tool for patients with ataxia

BACKGROUND AND OBJECTIVE

Early onset ataxias (EOAs) are a heterogeneous group of neurological conditions, responsible for severe motor disability in paediatric age, which still lack reliable outcome measures. Available scales to assess ataxia, such as the Scale for Assessment and Rating of Ataxia (SARA), are based on subjective assessment of specific motor and language tasks by an examiner, and therefore is age dependent and lacks accuracy in detecting small variations in disease severity. In last years, novel technologies, including computer interfaces and videogames, have emerged for clinical applications and the advent of Internet of Medical Things and of Information Communication Technology have allowed the remote control of such technologies. This pilot study describes a newly developed tool (SaraHome) for the assessment at home of EOA evaluating its feasibility and acceptability on a small sample of children.

METHODS

Ten EOA children and ten caregivers have been enrolled for a preliminary outpatient evaluation. The Microsoft Kinect 2.0 and Leap Motion Controller (LMC) connected to a personal computer with an ad hoc software have been set-up, for the acquisition of standardized motor tasks performed by the patients with the caregivers' assistance. Acceptance and practicability have been tested by QUEST 2.0 and IMI questionnaires in caregivers and patients respectively.

RESULTS

The SaraHome software was developed, based on a collection of services provided by a complex architecture that consists of a Restful interface, which enables to access a series of plugins for the execution of different tasks. A graphical user interface allows the acquisition of the patient movements while performing a motor task. A protocol of standard tasks inspired by SARA was established, and a system of video-assisted instruction provided. The set-up for the optimal acquisition of such protocol by Kinect and LMC has been defined. Both patients and caregivers accomplished the SaraHome assessment with good feedback at the technology acceptance questionnaires.

CONCLUSIONS

SaraHome represents a newly developed tool for the assessment of ataxia in patients, resulting from the integration of low-cost and easy-accessible technologies. This pilot application highlighted the feasibility and the acceptability of the system, suggesting the potential use in clinical practice.

Predicting Upper Limb Motor Impairment Recovery after Stroke: A Mixture Model

OBJECTIVE

Spontaneous recovery is an important determinant of upper extremity recovery after stroke and has been described by the 70% proportional recovery rule for the Fugl-Meyer motor upper extremity (FM-UE) scale. However, this rule is criticized for overestimating the predictability of FM-UE recovery. Our objectives were to develop a longitudinal mixture model of FM-UE recovery, identify FM-UE recovery subgroups, and internally validate the model predictions.

METHODS

We developed an exponential recovery function with the following parameters: subgroup assignment probability, proportional recovery coefficient r k , time constant in weeks τ k , and distribution of the initial FM-UE scores. We fitted the model to FM-UE measurements of 412 first-ever ischemic stroke patients and cross-validated endpoint predictions and FM-UE recovery cluster assignment.

RESULTS

The model distinguished 5 subgroups with different recovery parameters ( r1 = 0.09, τ1 = 5.3, r2 = 0.46, τ2 = 10.1, r3 = 0.86, τ3 = 9.8, r4 = 0.89, τ4 = 2.7, r5 = 0.93, τ5 = 1.2). Endpoint FM-UE was predicted with a median absolute error of 4.8 (interquartile range [IQR] = 1.3-12.8) at 1 week poststroke and 4.2 (IQR = 1.3-9.8) at 2 weeks. Overall accuracy of assignment to the poor (subgroup 1), moderate (subgroups 2 and 3), and good (subgroups 4 and 5) FM-UE recovery clusters was 0.79 (95% equal-tailed interval [ETI] = 0.78-0.80) at 1 week poststroke and 0.81 (95% ETI = 0.80-0.82) at 2 weeks.

INTERPRETATION

FM-UE recovery reflects different subgroups, each with its own recovery profile. Cross-validation indicates that FM-UE endpoints and FM-UE recovery clusters can be well predicted. Results will contribute to the understanding of upper limb recovery patterns in the first 6 months after stroke. ANN NEUROL 2020;87:383-393 Ann Neurol 2020;87:383-393.

Alternative routes for recovery of hand functions after corticospinal tract injury in primates and rodents

PURPOSE OF REVIEW

Recent studies on various corticospinal tract (CST) lesions have shown the plastic changes at a variety of motor systems after the lesion. This review provides the alternative routes associated with the motor functional recovery after the CST lesions at various levels in nonhuman primates and rodents.

RECENT FINDINGS

In the case of the motor cortical lesions, the perilesional area compensates for the lesion. In contrast, sprouting of the corticoreticular tracts was observed after the lesions involving sensorimotor cortical areas. After the internal capsule lesion, sprouting in the cortico-rubral pathway contributes to the recovery. In case of the pyramidal lesion, rubrospinal and reticulospinal tracts play a role of the functional recovery. After the dorsolateral funiculus (DLF) lesion at C4/C5, the indirect pathway via propriospinal tract contributes to the recovery. In case of the hemisection at lower cervical cord, the CST fibers sprouted from the bilateral motor cortex and descended to the contralesional DLF and crossed below the lesion area.

SUMMARY

The central pathways can change their structure and activity dynamically depending on the lesion sites and size. Revealing the difference of the alternative pathways should be crucial to understand the whole recovery mechanism and develop the further neurorehabilitative treatment.

Altered trajectories of neurodevelopment and behavior in mouse models of Rett syndrome

Rett Syndrome (RTT) is a genetic disorder that is caused by mutations in the x-linked gene coding for methyl-CpG-biding-protein 2 (MECP2) and that mainly affects females. Male and female transgenic mouse models of RTT have been studied extensively, and we have learned a great deal regarding RTT neuropathology and how MeCP2 deficiency may be influencing brain function and maturation. In this manuscript we review what is known concerning structural and coinciding functional and behavioral deficits in RTT and in mouse models of MeCP2 deficiency. We also introduce our own corroborating data regarding behavioral phenotype and morphological alterations in volume of the cortex and striatum and the density of neurons, aberrations in experience-dependent plasticity within the barrel cortex and the impact of MeCP2 loss on glial structure. We conclude that regional structural changes in genetic models of RTT show great similarity to the alterations in brain structure of patients with RTT. These region-specific modifications often coincide with phenotype onset and contribute to larger issues of circuit connectivity, progression, and severity. Although the alterations seen in mouse models of RTT appear to be primarily due to cell-autonomous effects, there are also non-cell autonomous mechanisms including those caused by MeCP2-deficient glia that negatively impact healthy neuronal function. Collectively, this body of work has provided a solid foundation on which to continue to build our understanding of the role of MeCP2 on neuronal and glial structure and function, its greater impact on neural development, and potential new therapeutic avenues.

Data-driven analyses of motor impairments in animal models of neurological disorders

Behavior provides important insights into neuronal processes. For example, analysis of reaching movements can give a reliable indication of the degree of impairment in neurological disorders such as stroke, Parkinson disease, or Huntington disease. The analysis of such movement abnormalities is notoriously difficult and requires a trained evaluator. Here, we show that a deep neural network is able to score behavioral impairments with expert accuracy in rodent models of stroke. The same network was also trained to successfully score movements in a variety of other behavioral tasks. The neural network also uncovered novel movement alterations related to stroke, which had higher predictive power of stroke volume than the movement components defined by human experts. Moreover, when the regression network was trained only on categorical information (control = 0; stroke = 1), it generated predictions with intermediate values between 0 and 1 that matched the human expert scores of stroke severity. The network thus offers a new data-driven approach to automatically derive ratings of motor impairments. Altogether, this network can provide a reliable neurological assessment and can assist the design of behavioral indices to diagnose and monitor neurological disorders.

Temporal Features of Muscle Synergies in Sit-to-Stand Motion Reflect the Motor Impairment of Post-Stroke Patients

Sit-to-stand (STS) motion is an important daily activity, and many post-stroke patients have difficulty performing STS motion. Previous studies found that there are four muscle synergies (synchronized muscle activations) in the STS motion of healthy adults. However, for post-stroke patients, it is unclear whether muscle synergies change and which features primarily reflect motor impairment. Here, we use a machine learning method to demonstrate that temporal features in two muscle synergies that contribute to hip rising and balance maintenance motion reflect the motor impairment of post-stroke patients. Analyzing the muscle synergies of age-matched healthy elderly people ( n = 12 ) and post-stroke patients ( n = 33 ), we found that the same four muscle synergies could account for the muscle activity of post-stroke patients. Also, we were able to distinguish post-stroke patients from healthy people on the basis of the temporal features of these muscle synergies. Furthermore, these temporal features were found to correlate with motor impairment of post-stroke patients. We conclude that post-stroke patients can still utilize the same number of muscle synergies as healthy people, but the temporal structure of muscle synergies changes as a result of motor impairment. This could lead to a new rehabilitation strategy for post-stroke patients that focuses on activation timing of muscle synergies.

Animal models of developmental motor disorders: parallels to human motor dysfunction in cerebral palsy

Cerebral palsy (CP) is the most common motor disability in children. Much of the previous research on CP has focused on reducing the severity of brain injuries, whereas very few researchers have investigated the cause and amelioration of motor symptoms. This research focus has had an impact on the choice of animal models. Many of the commonly used animal models do not display a prominent CP-like motor phenotype. In general, rodent models show anatomically severe injuries in the central nervous system (CNS) in response to insults associated with CP, including hypoxia, ischemia, and neuroinflammation. Unfortunately, most rodent models do not display a prominent motor phenotype that includes the hallmarks of spasticity (muscle stiffness and hyperreflexia) and weakness. To study motor dysfunction related to developmental injuries, a larger animal model is needed, such as rabbit, pig, or nonhuman primate. In this work, we describe and compare various animal models of CP and their potential for translation to the human condition.

Human myeloperoxidase (hMPO) is expressed in neurons in the substantia nigra in Parkinson's disease and in the hMPO-α-synuclein-A53T mouse model, correlating with increased nitration and aggregation of α-synuclein and exacerbation of motor impairment

α-Synuclein (αSyn) is central to the neuropathology of Parkinson's disease (PD) due to its propensity for misfolding and aggregation into neurotoxic oligomers. Nitration/oxidation of αSyn leads to dityrosine crosslinking and aggregation. Myeloperoxidase (MPO) is an oxidant-generating enzyme implicated in neurodegenerative diseases. In the present work we have examined the impact of MPO in PD through analysis of postmortem PD brain and in a novel animal model in which we crossed a transgenic mouse expressing the human MPO (hMPO) gene to a mouse expressing human αSyn-A53T mutant (A53T) (hMPO-A53T). Surprisingly, our results show that in PD substantia nigra, the hMPO gene is expressed in neurons containing aggregates of nitrated αSyn as well as MPO-generated HOCl-modified epitopes. In our hMPO-A53T mouse model, we also saw hMPO expression in neurons but not mouse MPO. In the mouse model, hMPO was expressed in neurons colocalizing with nitrated αSyn, carbamylated lysine, nitrotyrosine, as well as HOCl-modified epitopes/proteins. RNAscope in situ hybridization confirmed hMPO mRNA expression in neurons. Interestingly, the hMPO protein expressed in hMPO-A53T brain is primarily the precursor proMPO, which enters the secretory pathway potentially resulting in interneuronal transmission of MPO and oxidative species. Importantly, the hMPO-A53T mouse model, when compared to the A53T model, exhibited significant exacerbation of motor impairment on rotating rods, balance beams, and wire hang tests. Further, hMPO expression in the A53T model resulted in earlier onset of end stage paralysis. Interestingly, there was a high concentration of αSyn aggregates in the stratum lacunosum moleculare of hippocampal CA2 region, which has been associated in humans with accumulation of αSyn pathology and neural atrophy in dementia with Lewy bodies. This accumulation of αSyn aggregates in CA2 was associated with markers of endoplasmic reticulum (ER) stress and the unfolded protein response with expression of activating transcription factor 4 (ATF4), C/EBP homologous protein (CHOP), MPO, and cleaved caspase-3. Together these findings suggest that MPO plays an important role in nitrative and oxidative damage that contributes to αSyn pathology in synucleinopathies.

[Neuroprostheses to compensate for motor impairments]

Neuroprostheses are medical devices which, interfaced with the nervous system, are able to provoke the artificial generation of nerve signals. These signals, correctly coded, can then be interpreted by target organs such as the muscles.

The functional role of beta-oscillations in the supplementary motor area during reaching and grasping after stroke: A question of structural damage to the corticospinal tract

Hand motor function is often severely affected in stroke patients. Non-satisfying recovery limits reintegration into normal daily life. Understanding stroke-related network changes and identifying common principles that might underlie recovered motor function is a prerequisite for the development of interventional therapies to support recovery. Here, we combine the evaluation of functional activity (multichannel electroencephalography) and structural integrity (diffusion tensor imaging) in order to explain the degree of residual motor function in chronic stroke patients. By recording neural activity during a reaching and grasping task that mimics activities of daily living, the study focuses on deficit-related neural activation patterns. The study showed that the functional role of movement-related beta desynchronization in the supplementary motor area (SMA) for residual hand motor function in stroke patients depends on the microstructural integrity of the corticospinal tract (CST). In particular, in patients with damaged CST, stronger task-related activity in the SMA was associated with worse residual motor function. Neither CST damage nor functional brain activity alone sufficiently explained residual hand motor function. The findings suggest a central role of the SMA in the motor network during reaching and grasping in stroke patients, the degree of functional relevance of the SMA is depending on CST integrity.

Clinical, pathophysiological and genetic features of motor symptoms in autosomal dominant Alzheimer's disease

Owing to an early and marked deposition of amyloid-β in the basal ganglia, autosomal dominant Alzheimer's disease could distinctly involve motor symptoms. Therefore, we aimed to assess the prevalence and characteristics of motor signs in autosomal dominant Alzheimer's disease. Baseline Unified Parkinson Disease Rating Scale part three scores (UPDRS-III) from 433 participants of the Dominantly Inherited Alzheimer's Network observational study were analysed. Motor symptoms were scrutinized with respect to associations with mutation carrier status, mutation site within PSEN1, basal ganglia amyloid-β as measured by Pittsburgh compound B PET, estimated years to symptom onset and Clinical Dementia Rating Scale-Sum of Boxes. Motor findings in mutation carriers were compared to patients with sporadic Alzheimer's disease using data of the National Alzheimer's Coordination Center. Mutation carriers showed motor findings at a higher frequency (28.4% versus 12.8%; P < 0.001) and severity (mean UPDRS-III scores 2.0 versus 0.4; P < 0.001) compared to non-carriers. Eleven of the 27 UPDRS-III items were statistically more frequently affected in mutation carriers after adjustment for multiple comparisons. Ten of these 11 items were subscale components of bradykinesia. In cognitively asymptomatic mutation carriers, dysdiadochokinesia was more frequent compared to non-carriers (right hand: 3.8% versus 0%; adjusted P = 0.023; left: 4.4% versus 0.6%; adjusted P = 0.031). In this cohort, the positive predictive value for mutation carrier status in cognitively asymptomatic participants (50% a priori risk) of dysdiadochokinesia was 100% for the right and 87.5% for the left side. Mutation carriers with motor findings more frequently were basal ganglia amyloid-β positive (84% versus 63.3%; P = 0.006) and showed more basal ganglia amyloid-β deposition (Pittsburgh compound B-standardized uptake value ratio 2.472 versus 1.928; P = 0.002) than those without. Frequency and severity of motor findings were greater in post-codon 200 PSEN1 mutations (36%; mean UPDRS-III score 3.03) compared to mutations pre-codon 200 PSEN1 (19.3%, P = 0.022; 0.91, P = 0.013). In mutation carriers, motor symptom severity was significantly positively correlated with basal ganglia amyloid-β deposition, Clinical Dementia Rating scores and estimated years to symptom onset. Mutation carriers with a Clinical Dementia Rating global score of 2 exhibited more pronounced motor symptoms than sporadic Alzheimer's disease patients with the same Clinical Dementia Rating global score (mean UPDRS-III scores 20.71 versus 5.96; P < 0.001). With a prevalence of approximately 30% and increasing severity with progression of dementia, motor symptoms are proven as a clinically relevant finding in autosomal dominant Alzheimer's disease, in particular in advanced dementia stages, that correlates with deposition of amyloid-β in the basal ganglia. In a very small per cent of cognitively asymptomatic members of families with autosomal dominant Alzheimer's disease, dysdiadochokinesia may increase the chance of an individual's status as mutation carrier.

Cortical circuit alterations precede motor impairments in Huntington's disease mice

Huntington's disease (HD) is a devastating hereditary movement disorder, characterized by degeneration of neurons in the striatum and cortex. Studies in human patients and mouse HD models suggest that disturbances of neuronal function in the neocortex play an important role in disease onset and progression. However, the precise nature and time course of cortical alterations in HD have remained elusive. Here, we use chronic in vivo two-photon calcium imaging to longitudinally monitor the activity of identified single neurons in layer 2/3 of the primary motor cortex in awake, behaving R6/2 transgenic HD mice and wildtype littermates. R6/2 mice show age-dependent changes in cortical network function, with an increase in activity that affects a large fraction of cells and occurs rather abruptly within one week, preceeding the onset of motor defects. Furthermore, quantitative proteomics demonstrate a pronounced downregulation of synaptic proteins in the cortex, and histological analyses in R6/2 mice and human HD autopsy cases reveal a reduction in perisomatic inhibitory synaptic contacts on layer 2/3 pyramidal cells. Taken together, our study provides a time-resolved description of cortical network dysfunction in behaving HD mice and points to disturbed excitation/inhibition balance as an important pathomechanism in HD.

Altered brain iron content and deposition rate in Huntington's disease as indicated by quantitative susceptibility MRI

Altered brain iron content in the striatum of premanifest and manifest Huntington's disease (HD) has been reported. However, its natural history remains unclear. This study aims to investigate altered brain iron content in premanifest and early HD, and the iron deposition rate in these patients through a longitudinal one-year follow-up test, with quantitative magnetic susceptibility as an iron imaging marker. Twenty-four gene mutation carriers divided into three groups (further-from-onset, closer-to-onset and early HD) and 16 age-matched healthy controls were recruited at baseline, and of these, 14 carriers and 7 controls completed the one-year follow-up. Quantitative magnetic susceptibility and effective transverse relaxation rate ( R 2 ∗ ) were measured at 7.0 Tesla and correlated with atrophy and available clinical and cognitive measurements. Higher susceptibility values indicating higher iron content in the striatum and globus pallidus were only observed in closer-to-onset (N = 6, p < 0.05 in caudate and p < 0.01 in putamen) and early HD (N = 9, p < 0.05 in caudate and globus pallidus and p < 0.01 in putamen). Similar results were found by R 2 ∗ measurement. Such increases directly correlated with HD CAG-age product score and brain atrophy, but not with motor or cognitive scores. More importantly, a significantly higher iron deposition rate (11.9%/years in caudate and 6.1%/years in globus pallidus) was firstly observed in closer-to-onset premanifest HD and early HD as compared to the controls. These results suggest that monitoring brain iron may provide further insights into the pathophysiology of HD disease progression, and may provide a biomarker for clinical trials.

State transitions in the substantia nigra reticulata predict the onset of motor deficits in models of progressive dopamine depletion in mice

Parkinson's disease (PD) is a progressive neurodegenerative disorder whose cardinal motor symptoms are attributed to dysfunction of basal ganglia circuits under conditions of low dopamine. Despite well-established physiological criteria to define basal ganglia dysfunction, correlations between individual parameters and motor symptoms are often weak, challenging their predictive validity and causal contributions to behavior. One limitation is that basal ganglia pathophysiology is studied only at end-stages of depletion, leaving an impoverished understanding of when deficits emerge and how they evolve over the course of depletion. In this study, we use toxin- and neurodegeneration-induced mouse models of dopamine depletion to establish the physiological trajectory by which the substantia nigra reticulata (SNr) transitions from the healthy to the diseased state. We find that physiological progression in the SNr proceeds in discrete state transitions that are highly stereotyped across models and correlate well with the prodromal and symptomatic stages of behavior.

Investigation of the Treatment and Living Assistance Needed by Patients with Young-Onset Parkinson's Disease

PURPOSE

This study assessed the symptoms, treatment, social systems use, and perception of living conditions of patients with young-onset Parkinson's disease (YOPD), and investigated the support needed by them.

METHOD

Among the 252 people who completed our questionnaire, we defined YOPD patients as those diagnosed as young onset or those with onset at ≤40 years. The data were compared with others.

RESULTS

There were 24 patients with YOPD (9.5%) (average age: 61.7 years), with an average disease duration 6.4 years longer (p < 0.01) and time until diagnosis 0.7 years longer (p < 0.1) than those of other patients. This group took 1.6 times more types of medicines, and time to their next appointment was 8.6 days shorter than that of other patients (p < 0.05). Patients with YOPD had more pulsive walking and more sweating (p < 0.05), and more motor fluctuation (p < 0.1). More patients with YOPD had a physical disability certificate but felt they were not obtaining the required services (p < 0.05). 45.0% of the YOPD group wanted to work more, more used information and communication equipment (p < 0.05), and more felt their medications were adequate (p < 0.1).

CONCLUSIONS

Increased awareness of YOPD is needed. YOPD patients have motor fluctuation because of the longer disease duration. Thus, the support of doctors and nurses, and frequent examination visits, are indispensable for controlling symptoms to achieve middle age developmental tasks. Increased support for care-giving, leisure-time activities, and work is also necessary and may help maintain the desire to work in this group.

Transcortical photothrombotic pyramidotomy model with persistent motor deficits

Traditional pyramidotomy models have a high mortality rate from breathing difficulties and show early recovery from the induced motor deficits. This study establishes a novel pyramidotomy technique in Sprague Dawley rats that generates persistent motor deficits and has a reduced mortality rate. We used viral neural tracing to identify the course and relative distribution of forelimb and hindlimb motor fibers (n = 9). On basis of the neural tracing data, the medullary pyramid was targeted dorsally from the cerebellar cortex for photothrombotic infarct lesioning (n = 18). The photothrombotic technique selectively destroyed the corticospinal fibers in the medullary pyramid with relative preservation of neighboring grey-matter tissue. MicroPET imaging using 2-deoxy-2-[¹⁸F]-fluoro-D-glucose (FDG-microPET) showed a decrease in regional cerebral glucose metabolism (rCGM) in the bilateral pyramid and ipsilateral sensory cortex (p < 0.001, FDR q < 0.05). In addition, the trapezoid bodies and superior olivary nuclei showed a decrease in rCGM, compatible with damage caused during the introduction of the optical fiber. Connected structures such as the inferior colliculi and auditory cortices also showed decreases in rCGM in both hemispheres (p < 0.001, FDR q < 0.05). There was a significant and persistent decrease in motor and sensory function in the contralateral limb following pyramidotomy, as demonstrated by performance in the single pellet reaching task and the foot-fault test. There was no operative mortality or loss of respiratory function in this study. These results indicate that photothrombotic pyramidotomy with a dorsal transcortical approach is a safe and reliable technique for generating a pyramidotomy model with persistent motor deficits.

Stronger prediction of motor recovery and outcome post-stroke by cortico-spinal tract integrity than functional connectivity

OBJECTIVES

To examine longitudinal changes in structural and functional connectivity post-stroke in patients with motor impairment, and define their importance for recovery and outcome at 12 months.

METHODS

First-time stroke patients (N = 31) were studied at 1-2 weeks, 3 months, and 12 months post-injury with a validated motor battery and resting-state fMRI to measure inter-hemispheric functional connectivity (FC). Fractional anisotropy (FA) of the cortico-spinal tract (CST) was derived from diffusion tensor imaging as a measure of white matter organization. ANOVAs were used to test for changes in FC, FA, and motor performance scores over time, and regression analysis related motor outcome to clinical and neuroimaging variables.

RESULTS

FA of the ipsilesional CST improved significantly from 3 to 12 months and was strongly correlated with motor performance. FA improved even in the absence of direct damage to the CST. Inter-hemispheric FC also improved over time, but did not correlate with motor performance at 12 months. Clinical variables (early motor score, education level, and age) predicted 80.4% of the variation of motor outcome, and FA increased the predictability to 84.6%. FC did not contribute to the prediction of motor outcome.

CONCLUSIONS

Stroke causes changes to the CST microstructure that can account for behavioral variability even in the absence of demonstrable lesion. Ipsilesional CST undergoes remodeling post-stroke, even past the three-month window when most of the motor recovery happens. FA of the CST, but not inter-hemispheric FC, can improve to the prediction of motor outcome based on early motor scores.

Bringing order to higher order motor disorders

Majority of movements in everyday situations are complex and involve volition, planning of the movement and selection of the motor programme, all occurring before movement execution. Higher order motor disorders may be defined as abnormal motor behaviours resulting from disruption of any of the cortical processes that precede execution of the motor act. They are common in patients with neurodegenerative disorders, psychiatric diseases and structural brain lesions. These abnormal behaviours may be overlooked in the clinic, unless specifically evoked by the examiner. We discuss clinical and pathophysiological aspects of higher order motor disorders including: (1) disorders of disinhibition, such as grasp reflex and grasping behaviour, utilisation and imitation behaviour, motor preservations and paratonia; (2) disorders of motor intention such as motor neglect and motor impersistence; (3) alien limb syndrome; and (4) motor overflow phenomena, such as mirror movements and synkinesias. A video illustration of each phenomenon is provided. We place the findings from recent neurophysiological studies within the framework of theories of motor control to provide better insight into pathophysiology of different disorders.

Altered activation and functional asymmetry of exner's area but not the visual word form area in a child with sudden-onset, persistent mirror writing

Mirror writing is often produced by healthy children during early acquisition of literacy, and has been observed in adults following neurological disorders or insults. The neural mechanisms responsible for involuntary mirror writing remain debated, but in healthy children, it is typically attributed to the delayed development of a process of overcoming mirror invariance while learning to read and write. We present an unusual case of sudden-onset, persistent mirror writing in a previously typical seven-year-old girl. Using her dominant right hand only, she copied and spontaneously produced all letters, words and sentences, as well as some numbers and objects, in mirror image. Additionally, she frequently misidentified letter orientations in perceptual assessments. Clinical, neuropsychological, and functional neuroimaging studies were carried out over sixteen months. Neurologic and ophthalmologic examinations and a standard clinical MRI scan of the head were normal. Neuropsychological testing revealed average scores on most tests of intellectual function, language function, verbal learning and memory. Visual perception and visual reasoning were average, with the exception of below average form constancy, and mild difficulties on some visual memory tests. Activation and functional connectivity of the reading and writing network was assessed with fMRI. During a reading task, the VWFA showed a strong response to words in mirror but not in normal letter orientation - similar to what has been observed in typically developing children previously - but activation was atypically reduced in right primary visual cortex and Exner's Area. Resting-state connectivity within the reading and writing network was similar to that of age-matched controls, but hemispheric asymmetry between the balance of motor-to-visual input was found for Exner's Area. In summary, this unusual case suggests that a disruption to visual-motor integration rather than to the VWFA can contribute to sudden-onset, persistent mirror writing in the absence of clinically detectable neurological insult.

Supplementary motor area syndrome after surgery for parasagittal meningiomas

BACKGROUND

Resection within the supplementary motor area (SMA) may be accompanied by dramatic motor deficits and speech arrest when the dominant hemisphere is involved, termed the SMA syndrome. Typically, the muscle tone of the paralyzed extremities is preserved, and in most cases, a complete or near complete recovery is seen within a few months. The SMA syndrome has not been recognized for extra-axial tumor surgery in approximation of the SMA.

METHODS

We observed the SMA syndrome in a patient operated for a parasagittal meningioma in the posterior frontal region, and this observation intrigued us to prospectively collect similar cases.

RESULTS

In the period from January 2010 to December 2015, we observed five patients who developed a partial SMA syndrome after surgery for frontal parasagittal meningiomas. The muscle tone was preserved in the affected extremities. All patients experienced improvement in motor function within a few days, and on follow-up, three out of five patients had recovered completely. Three of the patients had meningioma WHO grade II.

CONCLUSIONS

Surgically induced SMA syndrome can easily be confused with pyramidal weakness. This series of cases demonstrate that the syndrome may also develop after removal of extra-axial tumors and is probably underdiagnosed and underreported. The good functional prognosis is helpful in the preoperative counseling and follow-up of these patients.

Prospective associations between measures of gross and fine motor coordination in infants and objectively measured physical activity and sedentary behavior in childhood

One important determinant of childhood physical activity and sedentary behavior may be that of motor development in infancy. The present analyses aimed to investigate whether gross and fine motor delays in infants were associated with objective and self-reported activity in childhood. Data were from the UK Millennium Cohort Study, a prospective cohort study, involving UK children born on or around the millennium (September 2000 and January 2002). When children were 9 months old, parents reported children's fine and gross motor-coordination, and at 7 years, sports club attendance and daily TV viewing time. Children's physical activity was measured using accelerometers at 7 years. Adjusted regression models were used to examine associations between delayed motor development and accelerometry measured moderate-to-vigorous physical activity and sedentary behavior, and parent-reported sport club attendance and TV viewing time. In this sample (n = 13,021), gross motor delay in infancy was associated with less time in moderate-to-vigorous physical activity (B -5.0 95% confidence interval [CI] -6.8, -3.2) and more time sedentary (B 13.5 95% CI 9.3, 17.8) in childhood. Gross and fine motor delays during infancy were associated with a reduced risk of having high attendance at sports clubs in childhood (both relative risk [RR] 0.7, 95% CI 0.6, 0.9). Fine motor delays, but not gross delays, were also associated with an increased risk of having high TV viewing time (RR 1.3 95% CI 1.0, 1.6). Findings from the present study suggest that delays in motor development in infancy are associated with physical activity and sedentary time in childhood.

Sigma-1 receptor knockout increases α-synuclein aggregation and phosphorylation with loss of dopaminergic neurons in substantia nigra

Sigma-1 receptor (σ1R) is expressed in dopaminergic neurons of substantia nigra. Here, we show that σ1R knockout (σ1R-/-) mice, at age 6-12 months, appeared with age-related loss of dopaminergic neurons and decline of motor coordination. Levels of α-synuclein (αSyn) oligomers and fibrillar αSyn in substantia nigra of σ1R-/- mice were age-dependently increased without the changes in αSyn monomers. The phosphorylation of αSyn monomers or oligomers in dopaminergic neurons was enhanced in σ1R-/- mice. Levels of phosphorylated eIF2a and C/EBP homologous protein expression were elevated in σ1R-/- mice with decline of proteasome activity. Inhibition of endoplasmic reticulum stress by salubrinal recovered the αSyn phosphorylation and proteasome activity and prevented early oligomerization of αSyn in σ1R-/- mice. Rifampicin reduced the late increase of αSyn oligomers in σ1R-/- mice. Rifampicin or salubrinal could reduce the loss of dopaminergic neurons in σ1R-/- mice and improved their motor coordination. The results indicate that the σ1R deficiency through enhanced aggregation and phosphorylation of αSyn causes the loss of dopaminergic neurons leading to the decline of motor coordination.

Sleep and Parkinson Disease

Sleep disorders are prevalent in Parkinson disease (PD), a disease with well recognized motor dysfunction. Sleep related problems received little attention until the last three decades. Sleep disorders seen in PD patients include insomnia, excessive sleepiness, restless legs syndrome, REM sleep behavior disorder. Some of these can have significant impact and lower the quality of life in these patients. An understanding of sleep issues in PD can help identify them early and result in optimal management.

Visual and Motor Deficits in Grown-up Mice with Congenital Zika Virus Infection

Human infants with congenital Zika virus (ZIKV) infection exhibit a range of symptoms including microcephaly, intracranial calcifications, macular atrophy and arthrogryposis. More importantly, prognosis data have lagged far behind the recent outbreak of ZIKV in 2015. In this work, we allow congenitally ZIKV-infected mice to grow into puberty. These mice exhibited motor incoordination and visual dysfunctions, which can be accounted by anatomical defects in the retina and cerebellar cortex. In contrary, anxiety level of the ZIKV-infected mice is normal. The spectrum of anatomical and behavioral deficits is consistent across different mice. Our data provided evidence that may help predict the public health burden in terms of prognosis of ZIKV-related congenital brain malformations in an animal model. Our study provided behavioral evaluation for the prognosis of congenital ZIKV infection and provides a platform for screening and evaluation of drugs candidates and treatment aiming at improving regeneration of infected neurons to prevent sequelae caused by ZIKV infection of fetus.

Moderate injury in motor-sensory cortex causes behavioral deficits accompanied by electrophysiological changes in mice adulthood

Moderate traumatic brain injury (TBI) in children often happen when there’s a sudden blow to the frontal bone, end with long unconscious which can last for hours and progressive cognitive deficits. However, with regard to the influences of moderate TBI during children adulthood, injury-induced alterations of locomotive ability, long-term memory performance, and hippocampal electrophysiological firing changes have not yet been fully identified. In this study, lateral fluid percussion (LFP) method was used to fabricate moderate TBI in motor and somatosensory cortex of the 6-weeks-old mice. The motor function, learning and memory function, extracellular CA1 neural spikes were assessed during acute and subacute phase. Moreover, histopathology was performed on day post injury (DPI) 16 to evaluate the effect of TBI on tissue and cell morphological changes in cortical and hippocampal CA1 subregions. After moderate LFP injury, the 6-weeks-old mice showed severe motor deficits at the early stage in acute phase but gradually recovered later during adulthood. At the time points in acute and subacute phase after TBI, novel object recognition (NOR) ability and spatial memory functions were consistently impaired in TBI mice; hippocampal firing frequency and burst probability were hampered. Analysis of the altered burst firing shows a clear hippocampal theta rhythm drop. These electrophysiological impacts were associated with substantially lowered NOR preference as compared to the sham group during adulthood. These results suggest that moderate TBI introduced at motorsenory cortex in 6-weeks-old mice causes obvious motor and cognitive deficits during their adulthood. While the locomotive ability progressively recovers, the cognitive deficits persisted while the mice mature as adult mice. The cognitive deficits may be attributed to the general suppressing of whole neural network, which could be labeled by marked reduction of excitability in hippocampal CA1 subregion.

Ten Novel Mutations in Chinese Patients with Megalencephalic Leukoencephalopathy with Subcortical Cysts and a Long-Term Follow-Up Research

Objective

Megalencephalic leukoencephalopathy with subcortical cysts (MLC, OMIM 604004) is a rare neurological deterioration disease. We aimed to clarify clinical and genetic features of Chinese MLC patients.

Methods

Clinical information and peripheral venous blood of 20 patients and their families were collected, Sanger-sequencing and Multiple Ligation-dependent Probe Amplification were performed to make genetic analysis. Splicing-site mutation was confirmed with RT-PCR. UPD was detected by haplotype analysis. Follow-up study was performed through telephone for 27 patients.

Results

Out of 20 patients, macrocephaly, classic MRI features, motor development delay and cognitive impairment were detected in 20(100%), 20(100%), 17(85%) and 4(20%) patients, respectively. 20(100%) were clinically diagnosed with MLC. 19(95%) were genetically diagnosed with 10 novel mutations in MLC1, MLC1 and GlialCAM mutations were identified in 15 and 4 patients, respectively. Deletion mutation from exon4 to exon9 and a homozygous point mutation due to maternal UPD of chromosome22 in MLC1 were found firstly. c.598-2A>C in MLC1 leads to the skip of exon8. c.772-1G>C in MLC1 accounting for 15.5%(9/58) alleles in Chinese patients might be a founder or a hot-spot mutation. Out of 27 patients in the follow-up study, head circumference was ranged from 56cm to 61cm in patients older than 5yeas old, with a median of 57cm. Motor development delay and cognitive impairment were detected in 22(81.5%) and 5(18.5%) patients, respectively. Motor and cognitive deterioration was found in 5 (18.5%) and 2 patients (7.4%), respectively. Improvements and MRI recovery were first found in Chinese patients. Rate of seizures (45.5%), transient motor retrogress (45.5%) and unconsciousness (13.6%) after head trauma was much higher than that after fever (18.2%, 9.1%, 0%, respectively).

Significance

It’s a clinical and genetic analysis and a follow-up study for largest sample of Chinese MLC patients, identifying 10 novel mutations, expanding mutation spectrums and discovering clinical features of Chinese MLC patients.

The Validity of the Supports Intensity Scale for Adults With Motor Disability

We argue that the construct of support needs as used in the field of intellectual disability (ID) offers applicability for persons with motor disabilities. To explore the validity of the Supports Intensity Scale (SIS) in groups other than ID, we studied the criterion validity for persons with motor disability in a population sample. The SIS showed excellent criterion validity, explaining 62-69% of the variance depending on different combinations of variables suggested by the literature. A distinctive pattern of support needs specific to motor disability was evident, supporting the sensitivity of the SIS for this population. In conclusion, the SIS is found to be an appropriate and valid instrument for assessing support needs in persons with motor disabilities.

Somatic symptoms scale: Psychometric properties in clinical and normal sample

OBJECTIVE

To develop a Somatic Symptoms Scale based on the criteria of standard symptoms, and to examine its psychometric properties through exploratory factor analysis.

METHODS

The study was conducted from January, 2010 to May, 2011 at two teaching hospitals in Lahore city and comprised female adolescents with somatic symptoms diagnosed by a psychiatrist, and an equal number of adolescents with minor physical disability. All patients were recruited from psychiatric out-door units of different hospitals. All subjects were unmarried. Translated Urdu version of the Somatic Symptoms Scale was administered to each participant individually. They were instructed to read the scale carefully and select the response that was most appropriate. The assessment procedure was done in a separate room on the hospital premises.

RESULTS

There were 150 female adolescents with somatic symptoms and equal number of females with minor disability. The overall mean age was 15.50+/-1.67 years (range: 14-17 years).Exploratory factor analysis showed that the two groups were significantly different on conversion motor symptoms (p<0.001), conversion sensory symptoms (p<0.001), pain symptoms (p<0.001), hypochondriacal symptoms (p<0.001) and body dysmorphic symptoms (p<0.001).

CONCLUSIONS

The Somatic Symptoms Scale was found to be a valid and reliable measure which can be used as screening instrument for non-clinical population and as a diagnostic measure in clinical population.

[Neurological prognosis of floppy infants after health examinations]

OBJECTIVE

The term benign congenital hypotonia is retrospective and refers to infants who are hypotonic at birth or shortly thereafter but later show a normal tone. It encompasses many different pathological processes that affect the brain, motor unit, or both. The majority of affected children have cerebral hypotonia. An increased incidence of mental retardation, learning disabilities, and other sequelae of cerebral abnormality are evident later in life, despite the recovery of a normal muscle tone. We followed floppy infants who were pointed out as showing motor delay on health examinations at 4 or 9 months of age until at least 2 years of age.

METHODS

We selected 32 floppy infants (15 males and 17 females) born uneventfully, with no family history, major anomalies, or abnormal findings on brain imaging, and no chromosomal study (G-banding and fluorescence in situ hybridization), serum creatine kinase level, blood lactate and pyruvate level, or blood amino acid abnormalities.

RESULTS

All 32 infants achieved head control, but 2 failed to learn to sit unsupported. These two were diagnosed based on gene analysis with Rett syndrome and spinal muscular atrophy, respectively. Although 27 among the 32 patients became ambulant, 18 (67%) showed mental retardation and 5 (19%) also had autism spectrum disorder. Five patients who could not walk were suspected to have congenital myopathy or congenital malformation syndrome.

CONCLUSIONS

After learning to walk independently and recovery of the normal muscle tone, many floppy infants showing motor delay on health examinations at 4 or 9 months of age developed mental retardation and autism spectrum disorder. Prospective follow-up is necessary for early diagnosis and intervention. For patients showing no motor and mental development, further laboratory studies including appropriate gene analysis are important for a definite diagnosis.

Technologies for Assessment of Motor Disorders in Parkinson's Disease: A Review

Parkinson’s Disease (PD) is characterized as the commonest neurodegenerative illness that gradually degenerates the central nervous system. The goal of this review is to come out with a summary of the recent progress of numerous forms of sensors and systems that are related to diagnosis of PD in the past decades. The paper reviews the substantial researches on the application of technological tools (objective techniques) in the PD field applying different types of sensors proposed by previous researchers. In addition, this also includes the use of clinical tools (subjective techniques) for PD assessments, for instance, patient self-reports, patient diaries and the international gold standard reference scale, Unified Parkinson Disease Rating Scale (UPDRS). Comparative studies and critical descriptions of these approaches have been highlighted in this paper, giving an insight on the current state of the art. It is followed by explaining the merits of the multiple sensor fusion platform compared to single sensor platform for better monitoring progression of PD, and ends with thoughts about the future direction towards the need of multimodal sensor integration platform for the assessment of PD.

Wrist Actigraphy: A Simple Way to Record Motor Activity in Elderly Patients with Dementia and Apathy or Aberrant Motor Behavior

INTRODUCTION

In dementia, behavioral psychological symptoms are frequent and variable.

OBJECTIVE

To assess the value of wrist actigraphy as a measure of disorder in motor behavior especially apathy, aberrant motor behavior, agitation and anxiety.

METHODS

Cross sectional observational study of consecutive patients older than 75 years admitted to an intermediate care unit of a geriatric hospital ward during a two-year period. Psycho behavioral symptoms and cognitive status were assessed using the NPI scale and MMSE and diagnosis of dementia was done using DSMIV criteria. A wrist actigraph was worn for 10 days to record motor activity, sleep time and number of periods of sleep.

RESULTS

183 patients were included. Among patients with dementia, a significant decrease in motor activity was recorded in those with apathy from 9h to 12h and 18h to 21h (p <0.05) and in those with anxiety from 21h to 24h (p <0.05). Aberrant motor behavior in dementia was associated with a significant increase in motor activity from 21h to 24h (p <0.01). Agitation was not associated with a significant differences in motor activity.

CONCLUSIONS

Wrist actigraphy can be used to record motor activity in elderly patients with dementia especially in those with apathy and aberrant motor behavior.

Diabetes, race, and functional limitations in older U.S. men and women

AIMS

The presence of diabetes is associated with increased odds of difficulties in functional tasks but it remains unclear if the burden is similar by race.

METHODS

Our study included 122,004 non-Hispanic Black (NHB) and non-Hispanic White (NHW) adults ≥50 years from the U.S. National Health Interview Survey (2001-2012). Diabetes was defined as self-reported diagnosis or medication use. Functional limitations were defined as any self-reported difficulty in performing mobility tasks, general physical activities (GPA), or leisure and social activities (LSA). Logistic regression models were created to investigate the relationship of race with functional limitations accounting for key covariates, among men and women, by diabetes status.

RESULTS

Among older U.S. adults, NHB versus NHW women without diabetes had a higher odds of limitations in mobility (OR=1.39, 1.30-1.49) and LSA (OR=1.13, 1.05-1.23) without diabetes but a similar odds of these limitations with diabetes by race, after adjusting for age, income, education, obesity, arthritis, heart disease, stroke, COPD, and cancer. Interestingly, NHB versus NHW women had significantly lower odds of GPA, irrespective of diabetes status. However, NHB versus NHW men with diabetes had a persistently higher odds for mobility and LSA limitations with diabetes as follows: mobility (OR=1.30, 1.12-1.51) and LSA limitations (OR=1.07, 1.06-1.34). The interaction of race and diabetes was significant among women for mobility limitations (p<0.01), but not men.

CONCLUSIONS

The burden of functional limitations differs by race among both men and women with diabetes. Future studies should examine mechanisms underlying these differences to prevent progression to disability in older adults with diabetes.

Peripheral quantitative computed tomography (pQCT) reveals low bone mineral density in adolescents with motor difficulties

This is the first reported study to describe local bone mineral density, assess parameters of fracture risk and report history of fractures in adolescents with motor difficulties. Motor difficulties evidenced by poor coordination in adolescence should be considered a new risk factor for below-average bone strength and structure and fracture risk.

INTRODUCTION

Adolescents with motor difficulties are characterised by poor coordination and low levels of physical activity and fitness. It is possible these deficits translate into below-average bone strength and structure. The objectives of this study were to describe local bone mineral density (BMD), assess parameters of fracture risk (stress-strain index, SSI) and report history of fractures in this group.

METHODS

Thirty-three adolescents (13 females), mean age of 14.3 (SD = 1.5) years, with motor difficulties underwent peripheral quantitative computed tomography (pQCT) measurements at proximal (66 %) and distal (4 %) sites of the non-dominant radius (R4 and R66) and tibia (T4 and T66). One sample t test was used to compare Z-scores for total BMD, trabecular density, cortical density and stress strain index (SSI) against standardized norms.

RESULTS

Significant differences were present at R4 total density mean Z-score = -0.85 (SD = 0.7, p < 0.001), R66 cortical density mean Z-score = -0.74 (SD = 1.97, p = 0.038), R66 SSI mean Z-score = -1.00 (SD = 1.08, p < 0.001) and T66 SSI mean Z-score = -0.70 (SD = 1.15, p < 0.001). There was a higher incidence of fractures (26.9 %) compared to the normal population (3-9 %).

CONCLUSIONS

Motor difficulties in adolescence should be considered a risk factor for below-average bone strength and structure and fracture risk. Strategies are needed to improve bone health in this high-risk-group.

Decreased mitochondrial bioenergetics and calcium buffering capacity in the basal ganglia correlates with motor deficits in a nonhuman primate model of aging

Altered mitochondrial function in the basal ganglia has been hypothesized to underlie cellular senescence and promote age-related motor decline. We tested this hypothesis in a nonhuman primate model of human aging. Six young (6-8 years old) and 6 aged (20-25 years old) female Rhesus monkeys (Macaca mulatta) were behaviorally characterized from standardized video records. Additionally, we measured mitochondrial bioenergetics along with calcium buffering capacity in the substantia nigra and putamen (PUT) from both age groups. Our results demonstrate that the aged animals had significantly reduced locomotor activity and movement speed compared with younger animals. Moreover, aged monkeys had significantly reduced ATP synthesis capacity (in substantia nigra and PUT), reduced pyruvate dehydrogenase activity (in PUT), and reduced calcium buffering capacity (in PUT) compared with younger animals. Furthermore, this age-related decline in mitochondrial function in the basal ganglia correlated with decline in motor function. Overall, our results suggest that drug therapies designed to enhance altered mitochondrial function may help improve motor deficits in the elderly.

Gait analysis in a Mecp2 knockout mouse model of Rett syndrome reveals early-onset and progressive motor deficits

Rett syndrome (RTT) is a genetic disorder characterized by a range of features including cognitive impairment, gait abnormalities and a reduction in purposeful hand skills. Mice harbouring knockout mutations in the Mecp2 gene display many RTT-like characteristics and are central to efforts to find novel therapies for the disorder. As hand stereotypies and gait abnormalities constitute major diagnostic criteria in RTT, it is clear that motor and gait-related phenotypes will be of importance in assessing preclinical therapeutic outcomes. We therefore aimed to assess gait properties over the prodromal phase in a functional knockout mouse model of RTT. In male Mecp2 knockout mice, we observed alterations in stride, coordination and balance parameters at 4 weeks of age, before the onset of other overt phenotypic changes as revealed by observational scoring. These data suggest that gait measures may be used as a robust and early marker of MeCP2-dysfunction in future preclinical therapeutic studies.