Involuntary Arm Research Articles

7087 An Unusual Movement Disorder, Case of Diabetic Striatopathy!

Abstract Disclosure: S. Azmat: None. O. Lodhi: None. R. Safi: None. H. harb: None. H. Ashok: None. M.F. Siddiqui: None. J.L. Gilden: None. Background: Non-ketotic Hyperglycemia Hemichorea-Hemiballismus Syndrome (NKH-CB) is rare complication of poorly controlled diabetes mellitus (DM) characterized by continuous, irregular jerky movements localized to one side of the body. It is commonly seen in type 2 DM and is often presented in females of East Asian descent. NKH-CB is often misdiagnosed due to its rarity and radiographic features easily mistaken for intracerebral hemorrhage.Case: A 70-year-old Latino male with type 2 diabetes mellitus, hypertension, bipolar disorder and past history of two cerebrovascular accidents presented to ED with non-radiating, midsternal chest pain. ACS was ruled out with negative serial troponins and normal EKG. Vital signs were significant for elevated blood pressure 151/64 mmHg. Labs showed blood glucose=447 mg/dL. Physical examination revealed large amplitude involuntary movements in left upper and lower extremities and facial region. He also veered to the left when ambulating. The patient reported that these abnormal movements were occurring for last three weeks although sensation was preserved bilaterally. Code stroke was called; non-contrast CT showed unilateral hyper density of the right caudate and putamen with no evidence of acute intracranial hemorrhage or large arterial territory infarction. CT Angiogram did not show any signs of stenosis or occlusion. He received intravenous fluids and 8 units lispro insulin in ED. Was admitted for further evaluation and received basal/bolus insulin therapy with target blood glucose of 140-160 mg%. He also received risperidone for his mental condition. Subsequent testing revealed hemoglobin A1C of 16.9% (reference range: < 5.7%). MRI Brian showed unilateral T1 hyperintensity involving right caudate and putamen corresponding to the hypodensity seen on CT. Neurology service was consulted. Based on clinical signs/symptoms coupled with neuroimaging, he was diagnosed with non-ketotic Hyperglycemia Hemichorea-Hemiballismus Syndrome. On day 2 with resolution of hyperglycemia, amplitude and frequency of involuntary arm movements were minimal. The patient was discharged with Lantus 7 and metformin 1000 mg for DM and risperidone for symptoms management. Conclusion: Diabetic neuropathy is commonly known to result in small and/or large fiber sensorimotor polyneuropathy, proximal motor, and acute mononeuropathies as well as entrapments, radiculopathies, autonomic neuropathies, and even cognitive disorders. This case describes rare case of simultaneous NKH-CB with history of CVA and antipsychotic medication use in a patient with poorly controlled DM which resolved with treatment of hyperglycemia. Thus offers valuable insights into the diagnostic challenges associated with this condition as well as potential links to other neurological complications. One should also remain vigilant of potential onset of seizures commonly seen with NKH. Presentation: 6/3/2024

Visually induced involuntary arm, head, and torso movements.

We explored in 75s long trials the effects of visually induced self-rotation and displacement (SR&D) on the horizontally extended right arm of standing subjects (N = 12). A "tool condition" was included in which subjects held a long rod. The extent of arm movement was contingent on whether the arm was extended out Freely or Pointing at a briefly proprioceptively specified target position. The results were nearly identical when subjects held the rod. Subjects in the Free conditions showed significant unintentional arm deviations, averaging 55° in the direction opposite the induced illusory self-motion. Deviations in the Pointing conditions were on average a fifth of those in the Free condition. Deviations of head and torso positions also occurred in all conditions. Total arm and head deviations were the sum of deviations of the arm and head with respect to the torso and deviations of the torso with respect to space. Pointing subjects were able to detect and correct for arm and head deviations with respect to the torso but not for the arm and head deviations with respect to space due to deviations of the torso. In all conditions, arm, head, and torso deviations began before subjects experienced SR&D. We relate our findings to being an extension of the manual following response (MFR) mechanism to influence passive arm control and arm target maintenance as well. Visual-vestibular convergence at vestibular nuclei cells and multiple cortical movement related areas can explain our results, MFR results, and classical Pass Pointing. We distinguish two Phases in the induction of SR&D. In Phase 1, the visual stimulation period prior to SR&D onset, the arm, head, and torso deviations are first apparent, circa < 1 s after stimulus begins. They are augmented at the onset of Phase 2 that starts when SR&D is first sensed. In Phase 2, reaching movements first show curved paths that are compensatory for the Coriolis forces that would be generated on the reaching arm were subjects actually physically rotating. These movement deviations are in the opposite direction to the MFR and the arm, head, and torso deviations reported here. Our results have implications for vehicle control in environments that can induce illusory self motion and displacement.

Machine learning aided jump height estimate democratization through smartphone measures.

The peak height reached in a countermovement jump is a well established performance parameter. Its estimate is often entrusted to force platforms or body-worn inertial sensors. To date, smartphones may possibly be used as an alternative for estimating jump height, since they natively embed inertial sensors. For this purpose, 43 participants performed 4 countermovement jumps (172 in total) on two force platforms (gold standard). While jumping, participants held a smartphone in their hands, whose inertial sensor measures were recorded. After peak height was computed for both instrumentations, twenty-nine features were extracted, related to jump biomechanics and to signal time-frequency characteristics, as potential descriptors of soft tissues or involuntary arm swing artifacts. A training set (129 jumps - 75%) was created by randomly selecting elements from the initial dataset, the remaining ones being assigned to the test set (43 jumps - 25%). On the training set only, a Lasso regularization was applied to reduce the number of features, avoiding possible multicollinearity. A multi-layer perceptron with one hidden layer was trained for estimating the jump height from the reduced feature set. Hyperparameters optimization was performed on the multi-layer perceptron using a grid search approach with 5-fold cross validation. The best model was chosen according to the minimum negative mean absolute error. The multi-layer perceptron greatly improved the accuracy (4 cm) and precision (4 cm) of the estimates on the test set with respect to the raw smartphone measures estimates (18 and 16 cm, respectively). Permutation feature importance was performed on the trained model in order to establish the influence that each feature had on the outcome. The peak acceleration and the braking phase duration resulted the most influential features in the final model. Despite not being accurate enough, the height computed through raw smartphone measures was still among the most influential features. The study, implementing a smartphone-based method for jump height estimates, paves the way to method release to a broader audience, pursuing a democratization attempt.

The Effect of Dual-Task Exercise on an Unstable Surface on Involuntary Arm and Leg Movement and Balance in Stroke Patients

The Effect of Dual-Task Exercise on an Unstable Surface on Involuntary Arm and Leg Movement and Balance in Stroke Patients

A Grave Initial Presentation of Graves’ Disease in a Patient With Moyamoya

Background: Moyamoya syndrome is chronic stenoocclusive disease involving the intracranial internal carotid arteries and their proximal branches along with an associated condition, such as hyperthyroidism1. The concurrence of moyamoya and Graves’ disease is rare. Ischemic stroke in moyamoya syndrome is postulated to be precipitated by thyrotoxicosis-induced hemodynamic instability. Clinical Case: A 63-year old Korean female with history of moyamoya disease with two prior ischemic strokes, hypertension and type 2 diabetes mellitus presented to the ER with 6 hours of left leg weakness and involuntary arm movements. A code stroke was activated and neurologic examination was notable for left leg paresis and left arm stereotypy. CT head showed loss of gray-white matter differentiation in the right frontal lobe concerning for acute ischemia. CT angiography of the head and neck noted diffuse stenosis of intracerebral vasculature and significant stenosis of the cavernous and supraclinoid portions of the internal carotid arteries. MRI brain later confirmed an acute infarct in the right ACA distribution. Neuroimaging incidentally showed a multinodular goiter with a 1.7 cm right thyroid nodule. Subsequently TSH was obtained and resulted as <0.030 mcIU/mL (0.27-5.00 mcIU/mL) with a reflex FT4 of >7.00 ng/dL (0.6-1.8 ng/dL). A review of her prior TFTs showed biochemical euthyroidism. Due to iodinated contrast administration on admission, RAIU scan was deferred. Thyroid ultrasound showed multinodular goiter with diffuse increased vascularity and multiple TI-RADS 4 and 5 nodules bilaterally. On further questioning, the patient reported tachycardia, diarrhea, weight loss and decreased appetite prior to hospitalization. A diagnosis of Graves’ disease was confirmed with TSI of 70.7 IU/L (0.00-0.55 IU/L). She was started on methimazole 20 mg twice daily and propranolol 20 mg q6h. FT4 downtrend from >7.00 to 3.3 ng/dL at time of discharge. Following four weeks of methimazole 20 mg daily, FT4 normalized to 1.70 ng/dL. The patient chose to continue antithyroidal drug therapy for treatment of Graves’ disease. Conclusion: Thyroid function assessment should be considered when evaluating a patient with moyamoya and acute ischemic stroke. If moyamoya syndrome associated with Graves’ disease is identified, treatment should be aimed at maintenance of euthyroidism. Reference: 1. Scott RM, Smith ER. Moyamoya disease and moyamoya syndrome. N Engl J Med. 2009 Mar 19;360(12):1226-37. Disclaimer: The views expressed herein are those of the authors and do not reflect the official policy or position of Brooke Army Medical Center, the U.S. Army Medical Department, the U.S. Army Office of the Surgeon General, the Department of the Army, the Department of the Air Force and Department of Defense or the U.S. Government.

Diabetic hemiballismus in the context of euglycaemia

AbstractAn 84‐year‐old white British woman with a background history of type 2 diabetes, Alzheimer's dementia, gout and hypothyroidism presented with a four‐day history of sudden, involuntary left arm and left leg movements. She had venous blood glucose of 4.4mmol/L with normal pH on admission. She had normal inflammatory markers with no signs of acute infection. Initial computed tomography brain imaging showed a known stable meningioma with no acute haemorrhage or infarct. Of note she had an admission, six weeks prior, with falls and raised capillary blood glucose readings. On that admission, her HbA1c was noted to have increased to 146mmol/mol having been 57mmol/mol six months earlier. Her oral hypoglycaemic agents were up‐titrated. There was no documented episode of hyperosmolar hyperglycaemic state.Brain magnetic resonance imaging (MRI with contrast) showed right striatal T1 high signal typical of diabetes‐related hemiballismus. She was treated with tetrabenazine for two weeks which was stopped before discharge as there was complete resolution of involuntary arm and leg movements.Hemiballismus is a rare but well‐known complication of diabetes. It is typically seen in the setting of hyperglycaemia. Our patient presented with hemiballismus while euglycaemic in the setting of recent hyperglycaemia. Copyright © 2021 John Wiley &amp; Sons.

Learning to Collaborate From Simulation for Robot-Assisted Dressing

We investigated the application of haptic feedback control and deep reinforcement learning (DRL) to robot-assisted dressing. Our method uses DRL to simultaneously train human and robot control policies as separate neural networks using physics simulations. In addition, we modeled variations in human impairments relevant to dressing, including unilateral muscle weakness, involuntary arm motion, and limited range of motion. Our approach resulted in control policies that successfully collaborate in a variety of simulated dressing tasks involving a hospital gown and a T-shirt. In addition, our approach resulted in policies trained in simulation that enabled a real PR2 robot to dress the arm of a humanoid robot with a hospital gown. We found that training policies for specific impairments dramatically improved performance; that controller execution speed could be scaled after training to reduce the robot's speed without steep reductions in performance; that curriculum learning could be used to lower applied forces; and that multi-modal sensing, including a simulated capacitive sensor, improved performance.

Hypothesis to Explain Yawning, Cortisol Rise, Brain Cooling and Motor Cortex Involvement of Involuntary Arm Movement in Neurologically Impaired Patients

Association between the hormone cortisol and yawning has been found. The Thompson Cortisol Hypothesis proposed a link between yawning and rises in cortisol with further recent evidence from neuroscience showing communication between the motor cortex, brain-stem and hypothalamus. Hormonal and neuronal links form the proposed network that influences and also monitors cortisol and brain temperature regulation via the hypothalamus. Evidence supports the proposed connection between brain-stem, hypothalamus and motor cortex and further supports the Thompson Cortisol Hypothesis suggesting threshold levels of cortisol elicit yawning to cool the brain. Additionally, this may explain the well-known observed phenomenon known as parakinesia brachialis oscitans in brain-stem ischaemic stroke patients during involuntary yawning.

Voluntary motor commands reveal awareness and control of involuntary movement

The capacity to inhibit actions is central to voluntary motor control. However, the control mechanisms and subjective experience involved in voluntarily stopping an involuntary movement remain poorly understood. Here we examined, in humans, the voluntary inhibition of the Kohnstamm phenomenon, in which sustained voluntary contraction of shoulder abductors is followed by involuntary arm raising. Participants were instructed to stop the involuntary movement, hold the arm in a constant position, and ‘release’ the inhibition after ∼2s. Participants achieved this by modulating agonist muscle activity, rather than by antagonist contraction. Specifically, agonist muscle activity plateaued during this voluntary inhibition, and resumed its previous increase thereafter. There was no discernible antagonist activation. Thus, some central signal appeared to temporarily counter the involuntary motor drive, without directly affecting the Kohnstamm generator itself. We hypothesise a form of “negative motor command” to account for this novel finding. We next tested the specificity of the negative motor command, by inducing bilateral Kohnstamm movements, and instructing voluntary inhibition for one arm only. The results suggested negative motor commands responsible for inhibition are initially broad, affecting both arms, and then become focused. Finally, a psychophysical investigation found that the perceived force of the aftercontraction was significantly overestimated, relative to voluntary contractions with similar EMG levels. This finding is consistent with the hypothesis that the Kohnstamm generator does not provide an efference copy signal. Our results shed new light on this interesting class of involuntary movement, and provide new information about voluntary inhibition of action.

Anchoring the “floating arm”: Use of proprioceptive and mirror visual feedback from one arm to control involuntary displacement of the other arm

Arm movement control takes advantage of multiple inputs, including those originating from the contralateral arm. In the mirror paradigm, it has been suggested that control of the unseen arm, hidden by the mirror, is facilitated by the reflection of the other, moving arm. Although proprioceptive feedback originating from the moving arm, (the image of which is reflected in the mirror), is always coupled with visual feedback in the mirror paradigm, the former has received little attention. We recently showed that the involuntary arm movement following a sustained, isometric contraction, known as the “floating arm” or “Kohnstamm phenomenon”, was adjusted to the passive-motorized displacement of the other arm. However, provision of mirror feedback, that is, the reflection in the mirror of the passively moved arm, did not add to this coupling effect. Therefore, the interlimb coupling in the mirror paradigm may to a large extent have a proprioceptive origin rather than a visual origin. The objective of the present study was to decouple mirror feedback and proprioceptive feedback from the reflected, moving arm and evaluate their respective contributions to interlimb coupling in the mirror paradigm. First (in Experiment 1, under eyes-closed conditions), we found that masking the proprioceptive afferents of the passively moved arm (by co-vibrating the antagonistic biceps and triceps muscles) suppressed the interlimb coupling between involuntary displacement of one arm and passive displacement of the other. Next (in Experiment 2), we masked proprioceptive afferents of the passively moved arm and specifically evaluated mirror feedback. We found that interlimb coupling through mirror feedback (though significant) was weaker than interlimb coupling through proprioceptive feedback. Overall, the present results show that in the mirror paradigm, proprioceptive feedback is stronger and more consistent than visual-mirror feedback in terms of the impact on interlimb coupling.

Sensorimotor organization of a sustained involuntary movement.

Involuntary movements share much of the motor control circuitry used for voluntary movement, yet the two can be easily distinguished. The Kohnstamm phenomenon (where a sustained, hard push produces subsequent involuntary arm raising) is a useful experimental model for exploring differences between voluntary and involuntary movement. Both central and peripheral accounts have been proposed, but little is known regarding how the putative Kohnstamm generator responds to afferent input. We addressed this by obstructing the involuntary upward movement of the arm. Obstruction prevented the rising EMG pattern that characterizes the Kohnstamm. Importantly, once the obstruction was removed, the EMG signal resumed its former increase, suggesting a generator that persists despite peripheral input. When only one arm was obstructed during bilateral involuntary movements, only the EMG signal from the obstructed arm showed the effect. Upon release of the obstacle, the obstructed arm reached the same position and EMG level as the unobstructed arm. Comparison to matched voluntary movements revealed a preserved stretch response when a Kohnstamm movement first contacts an obstacle, and also an overestimation of the perceived contact force. Our findings support a hybrid central and peripheral account of the Kohnstamm phenomenon. The strange subjective experience of this involuntary movement is consistent with the view that movement awareness depends strongly on efference copies, but that the Kohnstamm generator does not produces efference copies.

Using voluntary motor commands to inhibit involuntary arm movements.

A hallmark of voluntary motor control is the ability to stop an ongoing movement. Is voluntary motor inhibition a general neural mechanism that can be focused on any movement, including involuntary movements, or is it mere termination of a positive voluntary motor command? The involuntary arm lift, or 'floating arm trick', is a distinctive long-lasting reflex of the deltoid muscle. We investigated how a voluntary motor network inhibits this form of involuntary motor control. Transcranial magnetic stimulation of the motor cortex during the floating arm trick produced a silent period in the reflexively contracting deltoid muscle, followed by a rebound of muscle activity. This pattern suggests a persistent generator of involuntary motor commands. Instructions to bring the arm down voluntarily reduced activity of deltoid muscle. When this voluntary effort was withdrawn, the involuntary arm lift resumed. Further, voluntary motor inhibition produced a strange illusion of physical resistance to bringing the arm down, as if ongoing involuntarily generated commands were located in a 'sensory blind-spot', inaccessible to conscious perception. Our results suggest that voluntary motor inhibition may be a specific neural function, distinct from absence of positive voluntary motor commands.

Motor contagion: the contribution of trajectory and end-points.

Increased involuntary arm movement deviation when observing an incongruent human arm movement has been interpreted as a strong indicator of motor contagion. Here, we examined the contribution of trajectory and end-point information on motor contagion by altering congruence between the stimulus and arm movement. Participants performed cyclical horizontal arm movements whilst simultaneously observing a stimulus representing human arm movement. The stimuli comprised congruent horizontal movements or vertical movements featuring incongruent trajectory and end-points. A novel, third, stimulus comprised curvilinear movements featuring congruent end-points, but an incongruent trajectory. In Experiment 1, our dependent variables indicated increased motor contagion when observing the vertical compared to horizontal movement stimulus. There was even greater motor contagion in the curvilinear stimulus condition indicating an additive effect of an incongruent trajectory comprising congruent end-points. In Experiment 2, this additive effect was also present when facing perpendicular to the display, and thus with end-points represented as a product of the movement rather than an external spatial reference. Together, these findings support the theory of event coding (Hommel et al., Behav Brain Sci 24:849-878, 2001), and the prediction that increased motor contagion takes place when observed and executed actions share common features (i.e., movement end-points).

Electromyographic Investigation of Hypnotic Arm Levitation: Differences Between Voluntary Arm Elevation and Involuntary Arm Levitation

Thirty-three volunteers were randomly exposed to 3 conditions: hypnotic arm levitation, holding up the arm voluntarily without hypnosis, and imagined arm lifting without hypnosis. Trapezius, deltoid, extensor digitorum, flexor digitorum profundus, biceps brachii, and triceps brachii muscles were measured. Strain and muscle activity during lifting and holding up the right arm for 3 minutes were used as dependent variables. During hypnotic arm levitation, the total muscle activity was lower than during holding it up voluntarily (p < .01); the activity in the deltoid was 27% lower (p < .001). Without hypnosis, the muscle activity showed a positive correlation with strain. However, there was no such correlation in the hypnotic condition. Apparently, it is possible to reduce strain and to objectively measure muscle activity in an uplifted arm through hypnotic arm levitation.

Hemipseudoathetosis due to a hemorrhage at the cervicomedullary junction

A 17-year-old male presented with spontaneous left neck pain and ipsilateral involuntary arm movements. Examination revealed left facial hypoesthesia, right-sided pyramidal signs, and proprioceptive loss in the left arm with pseudoathetosis (video). Cervical-spinal imaging suggested acute hemorrhage at the cervicomedullary junction (figure, A and B). The patient improved over …

Electrophysiological confirmation of the zona incerta as a target for surgical treatment of disabling involuntary arm movements in multiple sclerosis: use of local field potentials

Lesioning or chronic deep brain stimulation (DBS) of the nucleus ventralis intermedius results in abolition of tremor in the contralateral limbs in Parkinson's disease (PD) and also in essential tremor. Recently, chronic DBS of the subthalamic nucleus has also proved to be very effective in reducing contralateral limb tremor in PD. These targets have been less effective in controlling the complex limb tremor often seen in multiple sclerosis (MS). Consequently, other targets have been sought in cases of MS with tremor. We describe a patient with MS with disabling proximal and distal involuntary arm movements in whom we were able to obtain sustained control of contralateral arm tremor and achieve functional improvement of the affected arm by chronic DBS of the region of the zona incerta. We also highlight the important role played by local field potentials recorded from the brain, with simultaneous recording of corresponding EMGs, in target localisation.

The 'Alien Hand' after Mesencephalic Haemorrhage

The main features of the alien hand syndrome are denial of hand ownership and involuntary arm movements. The underlying lesions are usually medial frontal infarction or degeneration contralateral to the affected arm. We describe a patient who developed an alien hand syndrome of the right arm after mesencephalic haemorrhage together with bilateral internuclear ophthalmoplegia and hemisensory loss. Three previous intracranial bleedings had been asymptomatic. We discuss whether hemisensory disturbance in addition to mild optical ataxia may produce the picture of an alien hand syndrome.

Self-regulation of spasm and spasticity in cerebral palsy.

Four young adult cerebral palsied subjects with a mixture of spasticity and athetosis attended an experimental reflex training program for three one-hour sessions each week over an 18 month period. During each session on-line measures of contraction level and tonic stretch reflex sensitivity from the biceps brachii muscle were shown to the subject on meter displays. Subjects were asked to attempt to control the displays. They were given goals such as: (1) reduce both contraction level and reflex sensitivity displays to zero and (2) increase the contraction level display to 10% of maximum while keeping the reflex sensitivity display at a minimum. Achievement of goals was automatically sensed and used to activate a cassette tape of the subject's favourite music. Contraction level and reflex sensitivity scores were averaged over one-minute intervals to provide a record of long term progress. Elbow-angle and IEMG data were recorded on FM tape for off-line analysis. All four subjects learned to suppress involuntary muscle activity and resting tonic stretch reflex responses. They also learned to produce a two or three-fold variation in action tonic stretch reflex sensitivity while sustaining 10% maximum voluntary contraction. In other words, subjects learned to self-regulate spasm and spasticity at the elbow and to regulate tonic stretch reflex sensitivity independently of contraction level. A visual tracking task requiring voluntary movement about the elbow was employed to assess improvement in functional control of elbow movement. One athetotic subject improved tracking accuracy as a consequence of reducing the amount of involuntary arm movement while the other three subjects showed negligible improvement in functional control.

Measurement of involuntary arm movement in athetotic patients.

Visual tracking tests have been used to obtain a quantified statistical description of the involuntary movements of the arm about the elbow joint in a group of patients suffering from athetoid cerebral palsy. Three separate components of involuntary activity can be recognized and it is possible that each may be a different physiological mechanism. First there are irregular movements which are represented by a continuous power spectrum which decreases with increasing frequency, reaching a negligible value between 2-3 Hz. The second component is a rhythmical low frequency movement which is indicated by a predominant peak in the power spectrum at a frequency of 0·3-0·6 Hz. The presence of this peak was predicted in a previous paper because of underdamping demonstrated in the closed loop voluntary control of movement in athetosis. The third component is the athetoid action tremor in which both agonist and antagonist muscle groups contract vigorously but asynchronously at a frequency of 1·5-4 Hz.