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Sample records for rapid arm movements

  1. Movement trajectory smoothness is not associated with the endpoint accuracy of rapid multi-joint arm movements in young and older adults.

    Science.gov (United States)

    Poston, Brach; Van Gemmert, Arend W A; Sharma, Siddharth; Chakrabarti, Somesh; Zavaremi, Shahrzad H; Stelmach, George

    2013-06-01

    The minimum variance theory proposes that motor commands are corrupted by signal-dependent noise and smooth trajectories with low noise levels are selected to minimize endpoint error and endpoint variability. The purpose of the study was to determine the contribution of trajectory smoothness to the endpoint accuracy and endpoint variability of rapid multi-joint arm movements. Young and older adults performed arm movements (4 blocks of 25 trials) as fast and as accurately as possible to a target with the right (dominant) arm. Endpoint accuracy and endpoint variability along with trajectory smoothness and error were quantified for each block of trials. Endpoint error and endpoint variance were greater in older adults compared with young adults, but decreased at a similar rate with practice for the two age groups. The greater endpoint error and endpoint variance exhibited by older adults were primarily due to impairments in movement extent control and not movement direction control. The normalized jerk was similar for the two age groups, but was not strongly associated with endpoint error or endpoint variance for either group. However, endpoint variance was strongly associated with endpoint error for both the young and older adults. Finally, trajectory error was similar for both groups and was weakly associated with endpoint error for the older adults. The findings are not consistent with the predictions of the minimum variance theory, but support and extend previous observations that movement trajectories and endpoints are planned independently. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. COMPARING PUMA ROBOT ARM WITH THE HUMAN ARM MOVEMENTS; AN ALTERNATIVE ROBOTIC ARM SHOULDER DESIGN

    OpenAIRE

    Mustafa BOZDEMİR; Esat ADIGÜZEL

    1999-01-01

    Using the robotic arms instead of human power becomes increasingly widespread nowadays. Widening of the robotic arms usage field is parallel to improvement of movement capability of it. In this study PUMA Robotic Arm System that is a developed system of the robotic arms was compared with a human arm due to movement. A new joint was added to PUMA Robotic Arm System to have the movements similar to the human shoulder joint. Thus, a shoulder was designed that can make movements through the sides...

  3. Prediction in the Vestibular Control of Arm Movements.

    Science.gov (United States)

    Blouin, Jean; Bresciani, Jean-Pierre; Guillaud, Etienne; Simoneau, Martin

    2015-01-01

    The contribution of vestibular signals to motor control has been evidenced in postural, locomotor, and oculomotor studies. Here, we review studies showing that vestibular information also contributes to the control of arm movements during whole-body motion. The data reviewed suggest that vestibular information is used by the arm motor system to maintain the initial hand position or the planned hand trajectory unaltered during body motion. This requires integration of vestibular and cervical inputs to determine the trunk motion dynamics. These studies further suggest that the vestibular control of arm movement relies on rapid and efficient vestibulomotor transformations that cannot be considered automatic. We also reviewed evidence suggesting that the vestibular afferents can be used by the brain to predict and counteract body-rotation-induced torques (e.g., Coriolis) acting on the arm when reaching for a target while turning the trunk.

  4. Endpoints of arm movements to visual targets

    NARCIS (Netherlands)

    van den Dobbelsteen, John; Brenner, Eli; Smeets, Jeroen B J

    2001-01-01

    Reaching out for objects with an unseen arm involves using both visual and kinesthetic information. Neither visual nor kinesthetic information is perfect. Each is subject to both constant and variable errors. To evaluate how such errors influence performance in natural goal-directed movements, we

  5. Organization of arm movements. Motion is segmented.

    Science.gov (United States)

    Soechting, J F; Terzuolo, C A

    1987-10-01

    A kinematic analysis of human arm trajectories which underlie the production of learned, continuous movements (such as drawing of 'figure 8s' and stars) in free space is presented. The objective of this investigation was to see if a set of rules, which had been identified previously and which are appropriate for generating circular or elliptical motion of the wrist in an arbitrary plane, also hold true for arbitrary, learned trajectories provided one additional assumption is made: that apparently continuous complex movements are composed of unit segments. The results presented in this paper are consistent with this hypothesis. Furthermore, as predicted by the hypothesis, the wrist trajectory deviates little from planar motion in each segment while the plane of motion can change abruptly from one segment to the next.

  6. Action sounds modulate arm reaching movements

    Directory of Open Access Journals (Sweden)

    Ana Tajadura-Jiménez

    2016-09-01

    Full Text Available Our mental representations of our body are continuously updated through multisensory bodily feedback as we move and interact with our environment. Although it is often assumed that these internal models of body-representation are used to successfully act upon the environment, only a few studies have actually looked at how body-representation changes influence goal-directed actions, and none have looked at this in relation to body-representation changes induced by sound. The present work examines this question for the first time. Participants reached for a target object before and after adaptation periods during which the sounds produced by their hand tapping a surface were spatially manipulated to induce a representation of an elongated arm. After adaptation, participants’ reaching movements were performed in a way consistent with having a longer arm, in that their reaching velocities were reduced. These kinematic changes suggest auditory-driven recalibration of the somatosensory representation of the arm morphology. These results provide support to the hypothesis that one’s represented body size is used as a perceptual ruler to measure objects’ distances and to accordingly guide bodily actions.

  7. Bilateral movements increase sustained extensor force in the paretic arm.

    Science.gov (United States)

    Kang, Nyeonju; Cauraugh, James H

    2018-04-01

    Muscle weakness in the extensors poststroke is a common motor impairment. Unfortunately, research is unclear on whether bilateral movements increase extensor force production in the paretic arm. This study investigated sustained force production while stroke individuals maximally extended their wrist and fingers on their paretic arm. Specifically, we determined isometric force production in three conditions: (a) unilateral paretic arm, (b) unilateral nonparetic arm, and (c) bilateral (both arms executing the same movement simultaneously). Seventeen chronic stroke patients produced isometric sustained force by executing wrist and fingers extension in unilateral and bilateral contraction conditions. Mean force, force variability (coefficient of variation), and signal-to-noise ratio were calculated for each contraction condition. Analysis of two-way (Arm × Type of Condition: 2 × 2; Paretic or Nonparetic Arm × Unilateral or Bilateral Conditions) within-subjects ANOVAs revealed that the bilateral condition increased sustained force in the paretic arm, but reduced sustained force in the nonparetic arm. Further, although the paretic arm exhibited more force variability and less signal-to-noise ratio than the nonparetic arm during a unilateral condition, there were no differences when participants simultaneously executed isometric contractions with both arms. Our unique findings indicate that bilateral contractions transiently increased extensor force in the paretic arm. Implications for Rehabilitation Bilateral movements increased isometric wrsit extensor force in paretic arms and redcued force in nonparetic arms versus unilateral movements. Both paretic and nonparetic arms produced similar force variability and signal-to-noise ratio during bilateral movements. Increased sustained force in the paretic arm during the bilateral condition indicates that rehabilitation protocols based on bilateral movements may be beneficial for functional recovery.

  8. Velocity curves of human arm and speech movements.

    Science.gov (United States)

    Ostry, D J; Cooke, J D; Munhall, K G

    1987-01-01

    The velocity curves of human arm and speech movements were examined as a function of amplitude and rate in both continuous and discrete movement tasks. Evidence for invariance under scalar transformation was assessed and a quantitative measure of the form of the curve was used to provide information on the implicit cost function in the production of voluntary movement. Arm, tongue and jaw movements were studied separately. The velocity curves of tongue and jaw movement were found to differ in form as a function of movement duration but were similar for movements of different amplitude. In contrast, the velocity curves for elbow movements were similar in form over differences in both amplitude and duration. Thus, the curves of arm movement, but not those of tongue or jaw movement, were geometrically equivalent in form. Measurements of the ratio of maximum to average velocity in arm movement were compared with the theoretical values calculated for a number of criterion functions. For continuous movements, the data corresponded best to values computed for the minimum energy criterion; for discrete movement, values were in the range of those predicted for the minimum jerk and best stiffness criteria. The source of a rate dependent asymmetry in the form of the velocity curve of speech movements was assessed in a control study in which subjects produced simple raising and lowering movements of the jaw without talking. The velocity curves of the non-speech control gesture were similar in form to those of jaw movement in speech. These data, in combination with similar findings for human jaw movement in mastication, suggest that the asymmetry is not a direct consequence of the requirements of the task. The biomechanics and neural control of the orofacial system may be possible sources of this effect.

  9. Rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Schenck, C H; Montplaisir, J Y; Frauscher, B

    2013-01-01

    We aimed to provide a consensus statement by the International Rapid Eye Movement Sleep Behavior Disorder Study Group (IRBD-SG) on devising controlled active treatment studies in rapid eye movement sleep behavior disorder (RBD) and devising studies of neuroprotection against Parkinson disease (PD...

  10. A neuro-fuzzy system for characterization of arm movements.

    Science.gov (United States)

    Balbinot, Alexandre; Favieiro, Gabriela

    2013-02-21

    The myoelectric signal reflects the electrical activity of skeletal muscles and contains information about the structure and function of the muscles which make different parts of the body move. Advances in engineering have extended electromyography beyond the traditional diagnostic applications to also include applications in diverse areas such as rehabilitation, movement analysis and myoelectric control of prosthesis. This paper aims to study and develop a system that uses myoelectric signals, acquired by surface electrodes, to characterize certain movements of the human arm. To recognize certain hand-arm segment movements, was developed an algorithm for pattern recognition technique based on neuro-fuzzy, representing the core of this research. This algorithm has as input the preprocessed myoelectric signal, to disclosed specific characteristics of the signal, and as output the performed movement. The average accuracy obtained was 86% to 7 distinct movements in tests of long duration (about three hours).

  11. A Neuro-Fuzzy System for Characterization of Arm Movements

    Directory of Open Access Journals (Sweden)

    Alexandre Balbinot

    2013-02-01

    Full Text Available The myoelectric signal reflects the electrical activity of skeletal muscles and contains information about the structure and function of the muscles which make different parts of the body move. Advances in engineering have extended electromyography beyond the traditional diagnostic applications to also include applications in diverse areas such as rehabilitation, movement analysis and myoelectric control of prosthesis. This paper aims to study and develop a system that uses myoelectric signals, acquired by surface electrodes, to characterize certain movements of the human arm. To recognize certain hand-arm segment movements, was developed an algorithm for pattern recognition technique based on neuro-fuzzy, representing the core of this research. This algorithm has as input the preprocessed myoelectric signal, to disclosed specific characteristics of the signal, and as output the performed movement. The average accuracy obtained was 86% to 7 distinct movements in tests of long duration (about three hours.

  12. Transfer of adaptation between ocular saccades and arm movements.

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    Bock, Otmar; Schmitz, Gerd; Grigorova, Valentina

    2008-06-01

    Previous studies found little or no transfer of adaptation from reactive saccades to arm pointing movements, which suggests that the two motor systems rely on distinct adaptive mechanisms. However, this conclusion is based on experiments about the adaptation of response amplitudes, which is known to follow somewhat different principles than the adaptation of response directions. In the present study, we therefore investigate whether adapting the direction of reactive saccades will transfer to arm movements. We also test transfer in the opposite direction, from the arm to the eyes. Participants executed aimed saccades or arm movements from a central starting point towards visual targets in the participants' frontal plane. Targets were presented in eight possible locations along a circle of 20 cm radius about the starting point; each remained for 200 ms in one position, and was then displaced along the circle by -15 degrees . Participants from group E adapted to these double-stepped targets while executing eye movements, and were then tested for transfer while executing arm movements. The reciprocal design was used in participants from group A. Adaptive change in group A was about 14 degrees , while in group E it was only about 7 degrees . Transfer of adaptation was substantial, and was more pronounced when using the arm (i.e., eye-to-arm transfer in group E) rather than the eyes (i.e., arm-to-eye transfer in group A). Strong aftereffects were yielded in both groups. This pattern of findings implies that the adaptive change observed in our study was mainly based on recalibration rather than on cognitive strategies (strong aftereffects), that eyes and arm had access to a common adaptive mechanism (substantial transfer), and that the arm had better access than the eyes (larger adaptation and transfer when using the arm). When considering this outcome along with the available literature, it appears that arm and eyes may rely sometimes on a common and sometimes on

  13. Multi-Joint Coordination of Vertical Arm Movement

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    Ajay Seth

    2003-01-01

    Full Text Available A model of the human arm was developed to study coordination of multi-joint movement in the vertical plane. The arm was represented as a two-segment, two-degree of freedom dynamic system with net muscle torques acting at the shoulder and elbow. Kinematic data were collected from a subject who performed unrestrained vertical movements with only the initial and final hand elevations prescribed. Movements were performed with and without a hand-held load. The method of computed torques was implemented to obtain net muscle torques, which enables position and velocity feedback to be used to estimate joint angular accelerations that produce a more stable simulation of arm movement. The model simulation was then used to calculate the contributions of the net muscle torques, gravitational torques and velocity-interaction torques to the angular accelerations of the shoulder and elbow and also to the vertical acceleration of the hand. The net muscle torques and gravity were the prime movers of the arm. The velocity-dependent effects contributed little to the dynamics of arm movement and were, in fact, insignificant when the hand was loaded. The muscles of the shoulder and elbow acted synergistically to elevate the arm in the sagittal plane. The hand was accelerated upward by the elbow first, until the point of maximum elbow flexion, after which the shoulder became the prime mover. Gravity acted consistently to accelerate the hand downward. Coordination was notably invariant to changes in external load. Some compensation for load was observed in the control, and these differences were attributed mainly to an increase in system inertia.

  14. Assessment of arm movements during gait in stroke - the Arm Posture Score.

    Science.gov (United States)

    Johansson, Gudrun M; Frykberg, Gunilla E; Grip, Helena; Broström, Eva W; Häger, Charlotte K

    2014-09-01

    The purpose of the study was to apply the Arm Posture Score (APS) to a stroke population, since comprehensive measures to quantify arm swing in the affected and non-affected arms during gait are lacking. A further aim was to investigate how gait speed and upper limb function estimated by clinical measures are related to the APS in the stroke group. The APS is the summarized root mean square deviation (RMSD) from normal, based on kinematics. Four arm movements (sagittal and frontal planes) as well as six arm movements (incorporating transversal plane) were included in the calculation of APS, referred to as APS4 and APS6, respectively. The study population consisted of 25 persons with stroke and 25 age- and gender-matched controls. The APS measures were significantly different between the affected and non-affected arms, as well as between the affected arm and the non-dominant arm of the controls (p≤0.001). Spasticity significantly influenced both APS measures, while speed only had a significant effect on the APS4. The APS measures correlated significantly to clinical measures of upper limb function. Both APS measures seem to be useful indices to quantify and discriminate between impaired and normal arm swing during gait after stroke. The variability of rotational arm movements needs to be studied further before considering the additional value of the APS6 over the APS4. When interpreting the APS, complementary kinematics should be taken into account, as the single value of the APS gives no information about the direction of the deviation. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Coordination between arm and leg movements during locomotion

    NARCIS (Netherlands)

    Donker, S.F.; Beek, P.J.; Wagenaar, R.C.; Mulder, T.

    To evaluate the contrasting dynamical and biomechanical interpretations of the 2:1 frequency coordination between arm and leg movements that occurs at low walking velocities and the 1:1 frequency coordination that occurs at higher walking velocities, the authors conducted an experiment in which they

  16. Locomotor-like leg movements evoked by rhythmic arm movements in humans.

    Directory of Open Access Journals (Sweden)

    Francesca Sylos-Labini

    Full Text Available Motion of the upper limbs is often coupled to that of the lower limbs in human bipedal locomotion. It is unclear, however, whether the functional coupling between upper and lower limbs is bi-directional, i.e. whether arm movements can affect the lumbosacral locomotor circuitry. Here we tested the effects of voluntary rhythmic arm movements on the lower limbs. Participants lay horizontally on their side with each leg suspended in an unloading exoskeleton. They moved their arms on an overhead treadmill as if they walked on their hands. Hand-walking in the antero-posterior direction resulted in significant locomotor-like movements of the legs in 58% of the participants. We further investigated quantitatively the responses in a subset of the responsive subjects. We found that the electromyographic (EMG activity of proximal leg muscles was modulated over each cycle with a timing similar to that of normal locomotion. The frequency of kinematic and EMG oscillations in the legs typically differed from that of arm oscillations. The effect of hand-walking was direction specific since medio-lateral arm movements did not evoke appreciably leg air-stepping. Using externally imposed trunk movements and biomechanical modelling, we ruled out that the leg movements associated with hand-walking were mainly due to the mechanical transmission of trunk oscillations. EMG activity in hamstring muscles associated with hand-walking often continued when the leg movements were transiently blocked by the experimenter or following the termination of arm movements. The present results reinforce the idea that there exists a functional neural coupling between arm and legs.

  17. A biologically inspired neural network controller for ballistic arm movements

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    Schmid Maurizio

    2007-09-01

    Full Text Available Abstract Background In humans, the implementation of multijoint tasks of the arm implies a highly complex integration of sensory information, sensorimotor transformations and motor planning. Computational models can be profitably used to better understand the mechanisms sub-serving motor control, thus providing useful perspectives and investigating different control hypotheses. To this purpose, the use of Artificial Neural Networks has been proposed to represent and interpret the movement of upper limb. In this paper, a neural network approach to the modelling of the motor control of a human arm during planar ballistic movements is presented. Methods The developed system is composed of three main computational blocks: 1 a parallel distributed learning scheme that aims at simulating the internal inverse model in the trajectory formation process; 2 a pulse generator, which is responsible for the creation of muscular synergies; and 3 a limb model based on two joints (two degrees of freedom and six muscle-like actuators, that can accommodate for the biomechanical parameters of the arm. The learning paradigm of the neural controller is based on a pure exploration of the working space with no feedback signal. Kinematics provided by the system have been compared with those obtained in literature from experimental data of humans. Results The model reproduces kinematics of arm movements, with bell-shaped wrist velocity profiles and approximately straight trajectories, and gives rise to the generation of synergies for the execution of movements. The model allows achieving amplitude and direction errors of respectively 0.52 cm and 0.2 radians. Curvature values are similar to those encountered in experimental measures with humans. The neural controller also manages environmental modifications such as the insertion of different force fields acting on the end-effector. Conclusion The proposed system has been shown to properly simulate the development of

  18. The Relationship Between Arm Movement and Walking Stability in Bipedal Walking

    National Research Council Canada - National Science Library

    Shibukawa, Miki

    2001-01-01

    ... analysis of walking for use in rehabilitation programs. The analysis of walking movement has generally focused on the legs rather than the arms, probably due to a perception that the arms do not play an essential role in this movement...

  19. Evaluating Classifiers to Detect Arm Movement Intention from EEG Signals

    Directory of Open Access Journals (Sweden)

    Daniel Planelles

    2014-09-01

    Full Text Available This paper presents a methodology to detect the intention to make a reaching movement with the arm in healthy subjects before the movement actually starts. This is done by measuring brain activity through electroencephalographic (EEG signals that are registered by electrodes placed over the scalp. The preparation and performance of an arm movement generate a phenomenon called event-related desynchronization (ERD in the mu and beta frequency bands. A novel methodology to characterize this cognitive process based on three sums of power spectral frequencies involved in ERD is presented. The main objective of this paper is to set the benchmark for classifiers and to choose the most convenient. The best results are obtained using an SVM classifier with around 72% accuracy. This classifier will be used in further research to generate the control commands to move a robotic exoskeleton that helps people suffering from motor disabilities to perform the movement. The final aim is that this brain-controlled robotic exoskeleton improves the current rehabilitation processes of disabled people.

  20. Movement structure in young and elderly adults during goal-directed movements of the left and right arm

    Science.gov (United States)

    Poston, Brach; Van Gemmert, Arend W.A.; Barduson, Beth; Stelmach, George E.

    2009-01-01

    Elderly adults often exhibit performance deficits during goal-directed movements of the dominant arm compared with young adults. Recent studies involving hemispheric lateralization have provided evidence that the dominant and non-dominant hemisphere-arm systems are specialized for controlling different movement parameters and that hemispheric specialization may be reduced during normal aging. The purpose was to examine age-related differences in the movement structure for the dominant (right) and non-dominant (left) during goal-directed movements. Young and elderly adults performed 72 aiming movements as fast and as accurately as possible to visual targets with both arms. The findings suggest that previous research utilizing the dominant arm can be generalized to the non-dominant arm because performance was similar for the two arms. However, as expected, the elderly adults showed shorter relative primary submovement lengths and longer relative primary submovement durations, reaction times, movement durations, and normalized jerk scores compared to the young adults. PMID:18556103

  1. Rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul

    2009-01-01

    and neurological disease. RBD is related to brainstem pathology. Furthermore, it is increasingly recognized that RBD is frequently related to Parkinsonian disorders and narcolepsy. This article reviews recent knowledge about RBD with focus on the diagnostic process and management. Udgivelsesdato: 2009-May......Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...

  2. Rapid eye movement sleep in breath holders.

    Science.gov (United States)

    Kohyama, J; Hasegawa, T; Shimohira, M; Fukumizu, M; Iwakawa, Y

    2000-07-01

    One-night polysomnography was performed on seven subjects suffering from breath-holding spells, including one whose death was suggested to be a consequence of a breath-holding spell. The fatal case showed no rapid eye movements (REMs) during REM sleep, although he exhibited REMs during wakefulness. The average numbers of both REMs and bursts of REMs in REM sleep in the other six breath holders were significantly lower than those in age-matched controls. The breath holders showed no airway obstruction, desaturation, or sleep fragmentation. Since the rapid ocular activity in REM sleep is generated in the brain stem, we hypothesized that a functional brainstem disturbance is involved in the occurrence of breath-holding spells.

  3. Research on the Optimization Method of Arm Movement in the Assembly Workshop Based on Ergonomics

    Science.gov (United States)

    Hu, X. M.; Qu, H. W.; Xu, H. J.; Yang, L.; Yu, C. C.

    2017-12-01

    In order to improve the work efficiency and comfortability, Ergonomics is used to research the work of the operator in the assembly workshop. An optimization algorithm of arm movement in the assembly workshop is proposed. In the algorithm, a mathematical model of arm movement is established based on multi rigid body movement model and D-H method. The solution of inverse kinematics equation on arm movement is solved through kinematics theory. The evaluation functions of each joint movement and the whole arm movement are given based on the comfortability of human body joint. The solution method of the optimal arm movement posture based on the evaluation functions is described. The software CATIA is used to verify that the optimal arm movement posture is valid in an example and the experimental result show the effectiveness of the algorithm.

  4. Movement Structure in Young and Elderly Adults during Goal-Directed Movements of the Left and Right Arm

    Science.gov (United States)

    Poston, Brach; Van Gemmert, Arend W. A.; Barduson, Beth; Stelmach, George E.

    2009-01-01

    Elderly adults often exhibit performance deficits during goal-directed movements of the dominant arm compared with young adults. Recent studies involving hemispheric lateralization have provided evidence that the dominant and non-dominant hemisphere-arm systems are specialized for controlling different movement parameters and that hemispheric…

  5. A boy infant with sleep related rhythmic movement disorder showing arm banging

    Directory of Open Access Journals (Sweden)

    Jun Kohyama

    2014-09-01

    Discussion: We diagnosed him as having arm banging type of sleep related rhythmic movement disorder. To our knowledge, no precise description on this type of sleep related rhythmic movement disorder has been found. In addition, this patient seemed to be the youngest case of sleep related rhythmic movement disorder showing arm banging.

  6. Single-Trial Neural Correlates of Arm Movement Preparation

    Science.gov (United States)

    Afshar, Afsheen; Santhanam, Gopal; Yu, Byron M.; Ryu, Stephen I.; Sahani, Maneesh; Shenoy, Krishna V.

    2011-01-01

    Summary The process by which neural circuitry in the brain plans and executes arm movements is not well understood. Prevailing data (single-neuron and field potential recordings) do not reveal how individual neurons’ activities are coordinated within the population, and thus inferences about how the neural circuit forms a motor plan have been indirect. Here we frame and test a new ‘initial condition hypothesis’ in which the reaction time (RT) of upcoming movements may be predicted on each trial using neurons’ moment-by-moment firing rates and rates of change of those rates. Using microelectrode array recordings from premotor cortex of monkeys performing delayed-reach movements, we compare such single-trial RT predictions to those of other theories. The initial condition hypothesis model can explain approximately four-fold more RT variance than the best alternative method. Thus, the initial condition hypothesis elucidates a new view of the relationship between single-trial preparatory neural population dynamics and single-trial behavior. PMID:21835350

  7. Human movement training with a cable driven ARm EXoskeleton (CAREX).

    Science.gov (United States)

    Mao, Ying; Jin, Xin; Gera Dutta, Geetanjali; Scholz, John P; Agrawal, Sunil K

    2015-01-01

    In recent years, the authors have proposed lightweight exoskeleton designs for upper arm rehabilitation using multi-stage cable-driven parallel mechanism. Previously, the authors have demonstrated via experiments that it is possible to apply "assist-as-needed" forces in all directions at the end-effector with such an exoskeleton acting on an anthropomorphic machine arm. A human-exoskeleton interface was also presented to show the feasibility of CAREX on human subjects. The goals of this paper are to 1) further address issues when CAREX is mounted on human subjects, e.g., generation of continuous cable tension trajectories 2) demonstrate the feasibility and effectiveness of CAREX on movement training of healthy human subjects and a stroke patient. In this research, CAREX is rigidly attached to an arm orthosis worn by human subjects. The cable routing points are optimized to achieve a relatively large "tensioned" static workspace. A new cable tension planner based on quadratic programming is used to generate continuous cable tension trajectory for smooth motion. Experiments were carried out on eight healthy subjects. The experimental results show that CAREX can help the subjects move closer to a prescribed circular path using the force fields generated by the exoskeleton. The subjects also adapt to the path shortly after training. CAREX was also evaluated on a stroke patient to test the feasibility of its use on patients with neural impairment. The results show that the patient was able to move closer to a prescribed straight line path with the "assist-as-needed" force field.

  8. Effects of anticipation certainty on preparatory brain activity and anticipatory postural adjustments associated with voluntary unilateral arm movement while standing.

    Science.gov (United States)

    Tomita, Hidehito; Fujiwara, Katsuo; Mori, Etsuko; Sakurai, Ayano

    2012-06-01

    We examined the effects of anticipation certainty concerning which voluntary movement is required in response to a stimulus while standing on preparatory brain activity and anticipatory postural adjustments (APAs). Ten right-handed adults abducted their left or right arm rapidly in response to a visual imperative stimulus, based on the type of stimulus. A warning cue, which did or did not contain information about the side of arm abduction, was presented 2000ms before the imperative stimulus. Preparatory brain activity before arm abduction was quantified by the mean amplitude of the contingent negative variation 100ms before the imperative stimulus (late CNV amplitude). Compared with the low anticipation condition, in the high anticipation condition the following results were obtained only in the case of right arm abduction: (1) larger late CNV amplitude, (2) earlier postural muscle activities with respect to the focal muscle of arm abduction, and (3) smaller peak displacement of center of pressure during the abduction. These findings suggest that high anticipation of voluntary movement of dominant arm to a stimulus while standing influences preparatory brain activity before the movement, resulting in earlier APAs and thus smaller disturbance of postural equilibrium during the movement. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. The Arm Movement Detection (AMD) test: a fast robotic test of proprioceptive acuity in the arm.

    Science.gov (United States)

    Mrotek, Leigh Ann; Bengtson, Maria; Stoeckmann, Tina; Botzer, Lior; Ghez, Claude P; McGuire, John; Scheidt, Robert A

    2017-06-28

    We examined the validity and reliability of a short robotic test of upper limb proprioception, the Arm Movement Detection (AMD) test, which yields a ratio-scaled, objective outcome measure to be used for evaluating the impact of sensory deficits on impairments of motor control, motor adaptation and functional recovery in stroke survivors. Subjects grasped the handle of a horizontal planar robot, with their arm and the robot hidden from view. The robot applied graded force perturbations, which produced small displacements of the handle. The AMD test required subjects to respond verbally to queries regarding whether or not they detected arm motions. Each participant completed ten, 60s trials; in five of the trials, force perturbations were increased in small increments until the participant detected motion while in the others, perturbations were decreased until the participant could no longer detect motion. The mean and standard deviation of the 10 movement detection thresholds were used to compute a Proprioceptive Acuity Score (PAS). Based on the sensitivity and consistency of the estimated thresholds, the PAS quantifies the likelihood that proprioception is intact. Lower PAS scores correspond to higher proprioceptive acuity. Thirty-nine participants completed the AMD test, consisting of 25 neurologically intact control participants (NIC), seven survivors of stroke with intact proprioception in the more affected limb (HSS+P), and seven survivors of stroke with impaired or absent proprioception in the more affected limb (HSS-P). Significant group differences were found, with the NIC and HSS+P groups having lower (i.e., better) PAS scores than the HSS-P group. A subset of the participants completed the AMD test multiple times and the AMD test was found to be reliable across repetitions. The AMD test required less than 15 min to complete and provided an objective, ratio-scaled measure of proprioceptive acuity in the upper limb. In the future, this test could be

  10. An MR-compatible gyroscope-based arm movement tracking system.

    Science.gov (United States)

    Shirinbayan, S Iman; Rieger, Jochem W

    2017-03-15

    Functional magnetic resonance imaging is well suited to link neural population activation with movement parameters of complex natural arm movements. However, currently existing MR-compatible arm tracking devices are not constructed to measure arm joint movement parameters of unrestricted movements. Therefore, to date most research focuses on simple arm movements or includes very little knowledge about the actual movement kinematics. We developed a low cost gyroscope-based arm movement tracking system (GAMTS) that features MR-compatibility. The system consists of dual-axis analogue gyroscopes that measure rotations of upper and lower arm joints. After MR artifact reduction, the rotation angles of the individual arm joints are calculated and used to animate a realistic arm model that is implemented in the OpenSim platform. The OpenSim platform can then provide the kinematics of any point on the arm model. In order to demonstrate the capabilities of the system, we first assessed the quality of reconstructed wrist movements in a low-noise environment where typical MR-related problems are absent and finally, we validated the reconstruction in the MR environment. The system provides the kinematics of the whole arm when natural unrestricted arm movements are performed inside the MR-scanner. The GAMTS is reliably capable of reconstructing the kinematics of trajectories and the reconstruction error is small in comparison with the movement induced variation of speed, displacement, and rotation. Moreover, the system can be used to probe brain areas for their correlation with movement kinematics. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Rapid eye movement sleep behavior disorder and rapid eye movement sleep without atonia in narcolepsy

    DEFF Research Database (Denmark)

    Dauvilliers, Yves; Jennum, Poul; Plazzi, Giuseppe

    2013-01-01

    Narcolepsy is a rare disabling hypersomnia disorder that may include cataplexy, sleep paralysis, hypnagogic hallucinations, and sleep-onset rapid eye movement (REM) periods, but also disrupted nighttime sleep by nocturnal awakenings, and REM sleep behavior disorder (RBD). RBD is characterized...... by dream-enacting behavior and impaired motor inhibition during REM sleep (REM sleep without atonia, RSWA). RBD is commonly associated with neurodegenerative disorders including Parkinsonisms, but is also reported in narcolepsy in up to 60% of patients. RBD in patients with narcolepsy is, however......, a distinct phenotype with respect to other RBD patients and characterized also by absence of gender predominance, elementary rather than complex movements, less violent behavior and earlier age at onset of motor events, and strong association to narcolepsy with cataplexy/hypocretin deficiency. Patients...

  12. The effect of arm weight support on upper limb muscle synergies during reaching movements

    OpenAIRE

    Coscia, Martina; Cheung, Vincent CK; Tropea, Peppino; Koenig, Alexander; Monaco, Vito; Bennis, Caoimhe; Micera, Silvestro; Bonato, Paolo

    2013-01-01

    Background: Compensating for the effect of gravity by providing arm-weight support (WS) is a technique often utilized in the rehabilitation of patients with neurological conditions such as stroke to facilitate the performance of arm movements during therapy. Although it has been shown that, in healthy subjects as well as in stroke survivors, the use of arm WS during the performance of reaching movements leads to a general reduction, as expected, in the level of activation of upper limb muscle...

  13. Stereotypical reaching movements of the octopus involve both bend propagation and arm elongation.

    Science.gov (United States)

    Hanassy, S; Botvinnik, A; Flash, T; Hochner, B

    2015-05-13

    The bend propagation involved in the stereotypical reaching movement of the octopus arm has been extensively studied. While these studies have analyzed the kinematics of bend propagation along the arm during its extension, possible length changes have been ignored. Here, the elongation profiles of the reaching movements of Octopus vulgaris were assessed using three-dimensional reconstructions. The analysis revealed that, in addition to bend propagation, arm extension movements involve elongation of the proximal part of the arm, i.e., the section from the base of the arm to the propagating bend. The elongations are quite substantial and highly variable, ranging from an average strain along the arm of -0.12 (i.e. shortening) up to 1.8 at the end of the movement (0.57 ± 0.41, n = 64 movements, four animals). Less variability was discovered in an additional set of experiments on reaching movements (0.64 ± 0.28, n = 30 movements, two animals), where target and octopus positions were kept more stationary. Visual observation and subsequent kinematic analysis suggest that the reaching movements can be broadly segregated into two groups. The first group involves bend propagation beginning at the base of the arm and propagating towards the arm tip. In the second, the bend is formed or present more distally and reaching is achieved mainly by elongation and straightening of the segment proximal to the bend. Only in the second type of movements is elongation significantly positively correlated with the distance of the bend from the target. We suggest that reaching towards a target is generated by a combination of both propagation of a bend along the arm and arm elongation. These two motor primitives may be combined to create a broad spectrum of reaching movements. The dynamical model, which recapitulates the biomechanics of the octopus muscular hydrostatic arm, suggests that achieving the observed elongation requires an extremely low ratio of longitudinal to transverse muscle

  14. Effects of palate depth, modified arm shape, and anchor screw on rapid maxillary expansion: a finite element analysis.

    Science.gov (United States)

    Matsuyama, Yosuke; Motoyoshi, Mitsuru; Tsurumachi, Niina; Shimizu, Noriyoshi

    2015-04-01

    This study examined the effects of palate depth, modifications of the arm shape, and anchor screw placement in the mid-palatal area on rapid maxillary expansion (RME) using finite element (FE) analysis. Three-dimensional FE models were constructed that included the maxilla (cortical and cancellous bone), maxillary sinus, maxillary first molar and first premolar, periodontal membrane, and an RME appliance with arms, bands, and anchor screws. The expansion screws were activated 0.2mm transversely. The deepest palate model had the smallest lateral displacement of the tooth and expansion of the mid-palatal suture and the greatest strain of the arm among the models with different palate heights. The model with a larger diameter arm had the smallest arm strain among the models with various arm shapes. The model with an anchor screw had the greatest lateral displacement of the tooth and expansion of the mid-palatal suture among all models. For a deeper palate, the arm strain increased and the effect of RME decreased. Modified arm shapes such as a larger diameter arm, arms connected by a diagonal wire, a straight arm, and a shorter arm efficiently expanded the maxillary dental arch. Anchor screws increased the effect of RME, generated more and closer bodily movement of the tooth, and parallel expansion of the mid-palatal suture. The model with an anchor screw without arms decreased the displacement of the teeth compared to the models with arms, so the arms are necessary for effective RME. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  15. Do the eyes scan dream images during rapid eye movement sleep? Evidence from the rapid eye movement sleep behaviour disorder model.

    Science.gov (United States)

    Leclair-Visonneau, Laurène; Oudiette, Delphine; Gaymard, Bertrand; Leu-Semenescu, Smaranda; Arnulf, Isabelle

    2010-06-01

    Rapid eye movements and complex visual dreams are salient features of human rapid eye movement sleep. However, it remains to be elucidated whether the eyes scan dream images, despite studies that have retrospectively compared the direction of rapid eye movements to the dream recall recorded after having awakened the sleeper. We used the model of rapid eye movement sleep behaviour disorder (when patients enact their dreams by persistence of muscle tone) to determine directly whether the eyes move in the same directions as the head and limbs. In 56 patients with rapid eye movement sleep behaviour disorder and 17 healthy matched controls, the eye movements were monitored by electrooculography in four (right, left, up and down) directions, calibrated with a target and synchronized with video and sleep monitoring. The rapid eye movement sleep behaviour disorder-associated behaviours occurred 2.1 times more frequently during rapid eye movement sleep with than without rapid eye movements, and more often during or after rapid eye movements than before. Rapid eye movement density, index and complexity were similar in patients with rapid eye movement sleep behaviour disorder and controls. When rapid eye movements accompanied goal-oriented motor behaviour during rapid eye movement sleep behaviour disorder (e.g. grabbing a fictive object, hand greetings, climbing a ladder), which happened in 19 sequences, 82% were directed towards the action of the patient (same plane and direction). When restricted to the determinant rapid eye movements, the concordance increased to 90%. Rapid eye movements were absent in 38-42% of behaviours. This directional coherence between limbs, head and eye movements during rapid eye movement sleep behaviour disorder suggests that, when present, rapid eye movements imitate the scanning of the dream scene. Since the rapid eye movements are similar in subjects with and without rapid eye movement sleep behaviour disorder, this concordance can be extended

  16. Multijoint arm stiffness during movements following stroke: implications for robot therapy.

    Science.gov (United States)

    Piovesan, D; Casadio, M; Mussa-Ivaldi, F A; Morasso, P G

    2011-01-01

    Impaired arm movements in stroke appear as a set of stereotypical kinematic patterns, characterized by abnormal joint coupling, which have a direct consequence on arm mechanics and can be quantified by the net arm stiffness at the hand. The current available measures of arm stiffness during functional tasks have limited clinical use, since they require several repetitions of the same test movement in many directions. Such procedure is difficult to obtain in stroke survivors who have lower fatigue threshold and increased variability compared to unimpaired individuals. The present study proposes a novel, fast quantitative measure of arm stiffness during movements by means of a Time-Frequency technique and the use of a reassigned spectrogram, applied on a trial-by-trial basis with a single perturbation. We tested the technique feasibility during robot mediated therapy, where a robot helped stroke survivors to regain arm mobility by providing assistive forces during a hitting task to 13 targets covering the entire reachable workspace. The endpoint stiffness of the paretic arm was estimated at the end of each hitting movements by suddenly switching of the assistive forces and observing the ensuing recoil movements. In addition, we considered how assistive forces influence stiffness. This method will provide therapists with improved tools to target the treatment to the individual's specific impairment and to verify the effects of the proposed exercises. © 2011 IEEE

  17. Different temporal bases for body and arm movements in volleyball serve reception

    NARCIS (Netherlands)

    Benerink, N. H.; Bootsma, R. J.; Zaal, F. T. J. M.

    2015-01-01

    In many sports, successfully intercepting a ball requires players to move both their body and their arms. Yet, studies of interception typically focus on one or the other. We performed an analysis of the moments of first foot and arm movements of elite-level volleyball players during serve

  18. Rapid eye movement sleep behavior disorder and rapid eye movement sleep without atonia in narcolepsy.

    Science.gov (United States)

    Dauvilliers, Yves; Jennum, Poul; Plazzi, Giuseppe

    2013-08-01

    Narcolepsy is a rare disabling hypersomnia disorder that may include cataplexy, sleep paralysis, hypnagogic hallucinations, and sleep-onset rapid eye movement (REM) periods, but also disrupted nighttime sleep by nocturnal awakenings, and REM sleep behavior disorder (RBD). RBD is characterized by dream-enacting behavior and impaired motor inhibition during REM sleep (REM sleep without atonia, RSWA). RBD is commonly associated with neurodegenerative disorders including Parkinsonisms, but is also reported in narcolepsy in up to 60% of patients. RBD in patients with narcolepsy is, however, a distinct phenotype with respect to other RBD patients and characterized also by absence of gender predominance, elementary rather than complex movements, less violent behavior and earlier age at onset of motor events, and strong association to narcolepsy with cataplexy/hypocretin deficiency. Patients with narcolepsy often present dissociated sleep features including RSWA, increased density of phasic chin EMG and frequent shift from REM to NREM sleep, with or without associated clinical RBD. Most patients with narcolepsy with cataplexy lack the hypocretin neurons in the lateral hypothalamus. Tonic and phasic motor activities in REM sleep and dream-enacting behavior are mostly reported in presence of cataplexy. Narcolepsy without cataplexy is a condition rarely associated with hypocretin deficiency. We proposed that hypocretin neurons are centrally involved in motor control during wakefulness and sleep in humans, and that hypocretin deficiency causes a functional defect in the motor control involved in the development of cataplexy during wakefulness and RBD/RSWA/phasic motor activity during REM sleep. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Goal-directed arm movements change eye-head coordination

    NARCIS (Netherlands)

    Smeets, Jeroen B J; Hayhoe, Mary M.; Ballard, Dana H.

    1996-01-01

    We compared the head movements accompanying gaze shifts while our subjects executed different manual operations, requiring gaze shifts of about 30°. The different tasks yielded different latencies between gaze shifts and hand movements, and different maximum velocities of the hand. These changes in

  20. Analysis of reaching movements of upper arm in robot assisted exercises. Kinematic assessment of robot assisted upper arm reaching single-joint movements.

    Science.gov (United States)

    Iuppariello, Luigi; D'Addio, Giovanni; Romano, Maria; Bifulco, Paolo; Lanzillo, Bernardo; Pappone, Nicola; Cesarelli, Mario

    2016-01-01

    Robot-mediated therapy (RMT) has been a very dynamic area of research in recent years. Robotics devices are in fact capable to quantify the performances of a rehabilitation task in treatments of several disorders of the arm and the shoulder of various central and peripheral etiology. Different systems for robot-aided neuro-rehabilitation are available for upper limb rehabilitation but the biomechanical parameters proposed until today, to evaluate the quality of the movement, are related to the specific robot used and to the type of exercise performed. Besides, none study indicated a standardized quantitative evaluation of robot assisted upper arm reaching movements, so the RMT is still far to be considered a standardised tool. In this paper a quantitative kinematic assessment of robot assisted upper arm reaching movements, considering also the effect of gravity on the quality of the movements, is proposed. We studied a group of 10 healthy subjects and results indicate that our advised protocol can be useful for characterising normal pattern in reaching movements.

  1. Analysis of Arm Movement Prediction by Using the Electroencephalography Signal

    Directory of Open Access Journals (Sweden)

    Reza Darmakusuma

    2016-04-01

    Full Text Available Various technological approaches have been developed in order to help those people who are unfortunateenough to be afflicted with different types of paralysis which limit them in performing their daily life activitiesindependently. One of the proposed technologies is the Brain-Computer Interface (BCI. The BCI system uses electroencephalography (EEG which is generated by the subject’s mental activityas input, and converts it into commands. Some previous experiments have shown the capability of the BCI system to predict the movement intention before the actual movement is onset. Thus research has predicted the movement by discriminating between data in the “rest” condition, wherethere is no movement intention, with “pre-movement” condition, where movement intention is detected before actual movement occurs. This experiment, however, was done to analyze the system for which machine learning was applied to data obtained in a continuous time interval, between 3 seconds before the movement was detected until 1 second after the actual movement was onset. This experiment shows that the system can discriminate the “pre-movement” condition and “rest” condition by using the EEG signal in 7-30 Hzwhere the Mu and Beta rhythm can be discovered with an average True Positive Rate (TPR value of 0.64 ± 0.11 and an average False Positive Rate (FPR of 0.17 ± 0.08. This experiment also shows that by using EEG signals obtained nearing the movement onset, the system has higher TPR or a detection rate in predicting the movement intention.

  2. A boy infant with sleep related rhythmic movement disorder showing arm banging.

    Science.gov (United States)

    Kohyama, Jun; Takano, Tomoyuki

    2014-09-01

    To present a male patient who performed arm banging on his face during sleep every night since 7 months of age. Clinical course of this patient with electroencephalographic recording with video recording at 23 months of age was shown. His arm banging began at the age of 7 months and showed no complete remission at the age of 57 months of age, although clonazepam revealed mild effects on its intensity and frequency. We diagnosed him as having arm banging type of sleep related rhythmic movement disorder. To our knowledge, no precise description on this type of sleep related rhythmic movement disorder has been found. In addition, this patient seemed to be the youngest case of sleep related rhythmic movement disorder showing arm banging.

  3. Integrated database for rapid mass movements in Norway

    Directory of Open Access Journals (Sweden)

    C. Jaedicke

    2009-03-01

    Full Text Available Rapid gravitational slope mass movements include all kinds of short term relocation of geological material, snow or ice. Traditionally, information about such events is collected separately in different databases covering selected geographical regions and types of movement. In Norway the terrain is susceptible to all types of rapid gravitational slope mass movements ranging from single rocks hitting roads and houses to large snow avalanches and rock slides where entire mountainsides collapse into fjords creating flood waves and endangering large areas. In addition, quick clay slides occur in desalinated marine sediments in South Eastern and Mid Norway. For the authorities and inhabitants of endangered areas, the type of threat is of minor importance and mitigation measures have to consider several types of rapid mass movements simultaneously.

    An integrated national database for all types of rapid mass movements built around individual events has been established. Only three data entries are mandatory: time, location and type of movement. The remaining optional parameters enable recording of detailed information about the terrain, materials involved and damages caused. Pictures, movies and other documentation can be uploaded into the database. A web-based graphical user interface has been developed allowing new events to be entered, as well as editing and querying for all events. An integration of the database into a GIS system is currently under development.

    Datasets from various national sources like the road authorities and the Geological Survey of Norway were imported into the database. Today, the database contains 33 000 rapid mass movement events from the last five hundred years covering the entire country. A first analysis of the data shows that the most frequent type of recorded rapid mass movement is rock slides and snow avalanches followed by debris slides in third place. Most events are recorded in the steep fjord

  4. Integrated database for rapid mass movements in Norway

    Science.gov (United States)

    Jaedicke, C.; Lied, K.; Kronholm, K.

    2009-03-01

    Rapid gravitational slope mass movements include all kinds of short term relocation of geological material, snow or ice. Traditionally, information about such events is collected separately in different databases covering selected geographical regions and types of movement. In Norway the terrain is susceptible to all types of rapid gravitational slope mass movements ranging from single rocks hitting roads and houses to large snow avalanches and rock slides where entire mountainsides collapse into fjords creating flood waves and endangering large areas. In addition, quick clay slides occur in desalinated marine sediments in South Eastern and Mid Norway. For the authorities and inhabitants of endangered areas, the type of threat is of minor importance and mitigation measures have to consider several types of rapid mass movements simultaneously. An integrated national database for all types of rapid mass movements built around individual events has been established. Only three data entries are mandatory: time, location and type of movement. The remaining optional parameters enable recording of detailed information about the terrain, materials involved and damages caused. Pictures, movies and other documentation can be uploaded into the database. A web-based graphical user interface has been developed allowing new events to be entered, as well as editing and querying for all events. An integration of the database into a GIS system is currently under development. Datasets from various national sources like the road authorities and the Geological Survey of Norway were imported into the database. Today, the database contains 33 000 rapid mass movement events from the last five hundred years covering the entire country. A first analysis of the data shows that the most frequent type of recorded rapid mass movement is rock slides and snow avalanches followed by debris slides in third place. Most events are recorded in the steep fjord terrain of the Norwegian west coast, but

  5. Influence of Arm Movement on Lesion Detection in PET/CT Imaging: Case Report

    Directory of Open Access Journals (Sweden)

    Yasemin Parlak

    2015-06-01

    Full Text Available Arm movement after the CT scan is a common artifact in PET/CT scanning. Motion artifacts may lead to difficulties in interpreting PET/CT images accurately. We report a 66 year old male patient with gastric cancer who underwent PET/CT for primary staging. He had a previous history of papillary thyroid cancer. In PET scan, there were striking cold artifacts at the level of arms. This is a classical sign of an accidental arm motion. A second scan was performed with the arms down due to the history of papillary thyroid cancer. The results were discussed.

  6. Modulation of arm reaching movements during processing of arm/hand-related action verbs with and without emotional connotation.

    Science.gov (United States)

    Spadacenta, Silvia; Gallese, Vittorio; Fragola, Michele; Mirabella, Giovanni

    2014-01-01

    The theory of embodied language states that language comprehension relies on an internal reenactment of the sensorimotor experience associated with the processed word or sentence. Most evidence in support of this hypothesis had been collected using linguistic material without any emotional connotation. For instance, it had been shown that processing of arm-related verbs, but not of those leg-related verbs, affects the planning and execution of reaching movements; however, at present it is unknown whether this effect is further modulated by verbs evoking an emotional experience. Showing such a modulation might shed light on a very debated issue, i.e. the way in which the emotional meaning of a word is processed. To this end, we assessed whether processing arm/hand-related verbs describing actions with negative connotations (e.g. to stab) affects reaching movements differently from arm/hand-related verbs describing actions with neutral connotation (e.g. to comb). We exploited a go/no-go paradigm in which healthy participants were required to perform arm-reaching movements toward a target when verbs expressing emotional hand actions, neutral hand actions or foot actions were shown, and to refrain from moving when no-effector-related verbs were presented. Reaction times and percentages of errors increased when the verb involved the same effector as used to give the response. However, we also found that the size of this interference decreased when the arm/hand-related verbs had a negative emotional connotation. Crucially, we show that such modulation only occurred when the verb semantics had to be retrieved. These results suggest that the comprehension of negatively valenced verbs might require the simultaneous reenactment of the neural circuitry associated with the processing of the emotion evoked by their meaning and of the neural circuitry associated with their motor features.

  7. Modulation of arm reaching movements during processing of arm/hand-related action verbs with and without emotional connotation.

    Directory of Open Access Journals (Sweden)

    Silvia Spadacenta

    Full Text Available The theory of embodied language states that language comprehension relies on an internal reenactment of the sensorimotor experience associated with the processed word or sentence. Most evidence in support of this hypothesis had been collected using linguistic material without any emotional connotation. For instance, it had been shown that processing of arm-related verbs, but not of those leg-related verbs, affects the planning and execution of reaching movements; however, at present it is unknown whether this effect is further modulated by verbs evoking an emotional experience. Showing such a modulation might shed light on a very debated issue, i.e. the way in which the emotional meaning of a word is processed. To this end, we assessed whether processing arm/hand-related verbs describing actions with negative connotations (e.g. to stab affects reaching movements differently from arm/hand-related verbs describing actions with neutral connotation (e.g. to comb. We exploited a go/no-go paradigm in which healthy participants were required to perform arm-reaching movements toward a target when verbs expressing emotional hand actions, neutral hand actions or foot actions were shown, and to refrain from moving when no-effector-related verbs were presented. Reaction times and percentages of errors increased when the verb involved the same effector as used to give the response. However, we also found that the size of this interference decreased when the arm/hand-related verbs had a negative emotional connotation. Crucially, we show that such modulation only occurred when the verb semantics had to be retrieved. These results suggest that the comprehension of negatively valenced verbs might require the simultaneous reenactment of the neural circuitry associated with the processing of the emotion evoked by their meaning and of the neural circuitry associated with their motor features.

  8. Modulation of Arm Reaching Movements during Processing of Arm/Hand-Related Action Verbs with and without Emotional Connotation

    Science.gov (United States)

    Spadacenta, Silvia; Gallese, Vittorio; Fragola, Michele; Mirabella, Giovanni

    2014-01-01

    The theory of embodied language states that language comprehension relies on an internal reenactment of the sensorimotor experience associated with the processed word or sentence. Most evidence in support of this hypothesis had been collected using linguistic material without any emotional connotation. For instance, it had been shown that processing of arm-related verbs, but not of those leg-related verbs, affects the planning and execution of reaching movements; however, at present it is unknown whether this effect is further modulated by verbs evoking an emotional experience. Showing such a modulation might shed light on a very debated issue, i.e. the way in which the emotional meaning of a word is processed. To this end, we assessed whether processing arm/hand-related verbs describing actions with negative connotations (e.g. to stab) affects reaching movements differently from arm/hand-related verbs describing actions with neutral connotation (e.g. to comb). We exploited a go/no-go paradigm in which healthy participants were required to perform arm-reaching movements toward a target when verbs expressing emotional hand actions, neutral hand actions or foot actions were shown, and to refrain from moving when no-effector-related verbs were presented. Reaction times and percentages of errors increased when the verb involved the same effector as used to give the response. However, we also found that the size of this interference decreased when the arm/hand-related verbs had a negative emotional connotation. Crucially, we show that such modulation only occurred when the verb semantics had to be retrieved. These results suggest that the comprehension of negatively valenced verbs might require the simultaneous reenactment of the neural circuitry associated with the processing of the emotion evoked by their meaning and of the neural circuitry associated with their motor features. PMID:25093410

  9. Cortical spectral activity and connectivity during active and viewed arm and leg movement

    Directory of Open Access Journals (Sweden)

    Julia eKline

    2016-03-01

    Full Text Available Active and viewed limb movement activate many similar neural pathways, however, to date most comparison studies have focused on subjects making small, discrete movements of the hands and feet. The purpose of this study was to determine if high-density electroencephalography (EEG could detect differences in cortical activity and connectivity during active and viewed rhythmic arm and leg movements in humans. Our primary hypothesis was that we would detect similar but weaker electrocortical spectral fluctuations and effective connectivity fluctuations during viewed limb exercise compared to active limb exercise due to the similarities in neural recruitment. A secondary hypothesis was that we would record stronger cortical spectral fluctuations for arm exercise compared to leg exercise, because rhythmic arm exercise would be more dependent on supraspinal control than rhythmic leg exercise. We recorded EEG data while ten young healthy subjects exercised on a recumbent stepper with: 1 both arms and legs, 2 just legs, and 3 just arms. Subjects also viewed video playback of themselves or another individual performing the same exercises. We performed independent component analysis, dipole fitting, spectral analysis, and effective connectivity analysis on the data. Cortical areas comprising the premotor and supplementary motor cortex, the anterior cingulate, the posterior cingulate, and the parietal cortex exhibited significant spectral fluctuations during rhythmic limb exercise. These fluctuations tended to be greater for the arms exercise conditions than for the legs only exercise condition, which suggests that human rhythmic arm movements are under stronger cortical control than rhythmic leg movements. We did not find consistent spectral fluctuations in these areas during the viewed conditions, but effective connectivity fluctuated at harmonics of the exercise frequency during both active and viewed rhythmic limb exercise. The right premotor and

  10. Cortical Spectral Activity and Connectivity during Active and Viewed Arm and Leg Movement.

    Science.gov (United States)

    Kline, Julia E; Huang, Helen J; Snyder, Kristine L; Ferris, Daniel P

    2016-01-01

    Active and viewed limb movement activate many similar neural pathways, however, to date most comparison studies have focused on subjects making small, discrete movements of the hands and feet. The purpose of this study was to determine if high-density electroencephalography (EEG) could detect differences in cortical activity and connectivity during active and viewed rhythmic arm and leg movements in humans. Our primary hypothesis was that we would detect similar but weaker electrocortical spectral fluctuations and effective connectivity fluctuations during viewed limb exercise compared to active limb exercise due to the similarities in neural recruitment. A secondary hypothesis was that we would record stronger cortical spectral fluctuations for arm exercise compared to leg exercise, because rhythmic arm exercise would be more dependent on supraspinal control than rhythmic leg exercise. We recorded EEG data while ten young healthy subjects exercised on a recumbent stepper with: (1) both arms and legs, (2) just legs, and (3) just arms. Subjects also viewed video playback of themselves or another individual performing the same exercises. We performed independent component analysis, dipole fitting, spectral analysis, and effective connectivity analysis on the data. Cortical areas comprising the premotor and supplementary motor cortex, the anterior cingulate, the posterior cingulate, and the parietal cortex exhibited significant spectral fluctuations during rhythmic limb exercise. These fluctuations tended to be greater for the arms exercise conditions than for the legs only exercise condition, which suggests that human rhythmic arm movements are under stronger cortical control than rhythmic leg movements. We did not find consistent spectral fluctuations in these areas during the viewed conditions, but effective connectivity fluctuated at harmonics of the exercise frequency during both active and viewed rhythmic limb exercise. The right premotor and supplementary motor

  11. The effect of arm weight support on upper limb muscle synergies during reaching movements.

    Science.gov (United States)

    Coscia, Martina; Cheung, Vincent C K; Tropea, Peppino; Koenig, Alexander; Monaco, Vito; Bennis, Caoimhe; Micera, Silvestro; Bonato, Paolo

    2014-03-04

    Compensating for the effect of gravity by providing arm-weight support (WS) is a technique often utilized in the rehabilitation of patients with neurological conditions such as stroke to facilitate the performance of arm movements during therapy. Although it has been shown that, in healthy subjects as well as in stroke survivors, the use of arm WS during the performance of reaching movements leads to a general reduction, as expected, in the level of activation of upper limb muscles, the effects of different levels of WS on the characteristics of the kinematics of motion and of the activity of upper limb muscles have not been thoroughly investigated before. In this study, we systematically assessed the characteristics of the kinematics of motion and of the activity of 14 upper limb muscles in a group of 9 healthy subjects who performed 3-D arm reaching movements while provided with different levels of arm WS. We studied the hand trajectory and the trunk, shoulder, and elbow joint angular displacement trajectories for different levels of arm WS. Besides, we analyzed the amplitude of the surface electromyographic (EMG) data collected from upper limb muscles and investigated patterns of coordination via the analysis of muscle synergies. The characteristics of the kinematics of motion varied across WS conditions but did not show distinct trends with the level of arm WS. The level of activation of upper limb muscles generally decreased, as expected, with the increase in arm WS. The same eight muscle synergies were identified in all WS conditions. Their level of activation depended on the provided level of arm WS. The analysis of muscle synergies allowed us to identify a modular organization underlying the generation of arm reaching movements that appears to be invariant to the level of arm WS. The results of this study provide a normative dataset for the assessment of the effects of the level of arm WS on muscle synergies in stroke survivors and other patients who could

  12. The effect of arm weight support on upper limb muscle synergies during reaching movements

    Science.gov (United States)

    2014-01-01

    Background Compensating for the effect of gravity by providing arm-weight support (WS) is a technique often utilized in the rehabilitation of patients with neurological conditions such as stroke to facilitate the performance of arm movements during therapy. Although it has been shown that, in healthy subjects as well as in stroke survivors, the use of arm WS during the performance of reaching movements leads to a general reduction, as expected, in the level of activation of upper limb muscles, the effects of different levels of WS on the characteristics of the kinematics of motion and of the activity of upper limb muscles have not been thoroughly investigated before. Methods In this study, we systematically assessed the characteristics of the kinematics of motion and of the activity of 14 upper limb muscles in a group of 9 healthy subjects who performed 3-D arm reaching movements while provided with different levels of arm WS. We studied the hand trajectory and the trunk, shoulder, and elbow joint angular displacement trajectories for different levels of arm WS. Besides, we analyzed the amplitude of the surface electromyographic (EMG) data collected from upper limb muscles and investigated patterns of coordination via the analysis of muscle synergies. Results The characteristics of the kinematics of motion varied across WS conditions but did not show distinct trends with the level of arm WS. The level of activation of upper limb muscles generally decreased, as expected, with the increase in arm WS. The same eight muscle synergies were identified in all WS conditions. Their level of activation depended on the provided level of arm WS. Conclusions The analysis of muscle synergies allowed us to identify a modular organization underlying the generation of arm reaching movements that appears to be invariant to the level of arm WS. The results of this study provide a normative dataset for the assessment of the effects of the level of arm WS on muscle synergies in stroke

  13. Moving events in time: time-referent hand–arm movements influence perceived temporal distance to past events

    OpenAIRE

    Semin, Gün Refik; Blom, Stephanie S. A. H.

    2013-01-01

    We examine and find support for the hypothesis that time-referent hand-arm movements influence temporal judgments. In line with the concept of ""left is associated with earlier times, and right is associated with later times,"" we show that performing left (right) hand-arm movements while thinking about a past event increases (decreases) the perceived temporal distance to the event. These findings show for the first time that hand-arm movements can influence the perceived temporal distance to...

  14. Characteristics of rapid eye movement sleep behavior disorder in narcolepsy

    DEFF Research Database (Denmark)

    Jennum, Poul Jørgen; Frandsen, Rune Asger Vestergaard; Knudsen, Stine

    2013-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by dream-enacting behavior and impaired motor inhibition during REM sleep (REM sleep without atonia, RSWA). RBD is commonly associated with Parkinsonian disorders, but is also reported in narcolepsy. Most patients with narcol...

  15. Neurophysiological basis of rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Jennum, Poul; Christensen, Julie Anja Engelhard; Zoetmulder, Marielle

    2016-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by a history of recurrent nocturnal dream enactment behavior and loss of skeletal muscle atonia and increased phasic muscle activity during REM sleep: REM sleep without atonia. RBD and associated comorbidities ha...

  16. Octopus arm movements under constrained conditions: adaptation, modification and plasticity of motor primitives.

    Science.gov (United States)

    Richter, Jonas N; Hochner, Binyamin; Kuba, Michael J

    2015-04-01

    The motor control of the eight highly flexible arms of the common octopus (Octopus vulgaris) has been the focus of several recent studies. Our study is the first to manage to introduce a physical constraint to an octopus arm and investigate the adaptability of stereotypical bend propagation in reaching movements and the pseudo-limb articulation during fetching. Subjects (N=6) were placed inside a transparent Perspex box with a hole at the center that allowed the insertion of a single arm. Animals had to reach out through the hole toward a target, to retrieve a food reward and fetch it. All subjects successfully adjusted their movements to the constraint without an adaptation phase. During reaching tasks, the animals showed two movement strategies: stereotypical bend propagation reachings, which were established at the hole of the Perspex box and variant waving-like movements that showed no bend propagations. During fetching movements, no complete pseudo-joint fetching was observed outside the box and subjects pulled their arms through the hole in a pull-in like movement. Our findings show that there is some flexibility in the octopus motor system to adapt to a novel situation. However, at present, it seems that these changes are more an effect of random choices between different alternative motor programs, without showing clear learning effects in the choice between the alternatives. Interestingly, animals were able to adapt the fetching movements to the physical constraint, or as an alternative explanation, they could switch the motor primitive fetching to a different motor primitive 'arm pulling'. © 2015. Published by The Company of Biologists Ltd.

  17. Rapid Eye Movement Sleep Behavior Disorder and Neurodegenerative Disease.

    Science.gov (United States)

    Howell, Michael Joseph; Schenck, Carlos Hugh

    2015-06-01

    The dream enactment of rapid eye movement sleep behavior disorder (RBD) is often the first indication of an impending α-synuclein disorder, such as Parkinson disease, multiple-system atrophy, or dementia with Lewy bodies. To provide an overview of RBD from the onset of dream enactment through the emergence of a parkinsonian disorder. Peer-reviewed articles, including case reports, case series, retrospective reviews, prospective randomized trials, and basic science investigations, were identified in a PubMed search of articles on RBD from January 1, 1986, through July 31, 2014. Under normal conditions, vivid dream mentation combined with skeletal muscle paralysis characterizes rapid eye movement sleep. In RBD, α-synuclein abnormalities in the brainstem disinhibit rapid eye movement sleep motor activity, leading to dream enactment. The behaviors of RBD are often theatrical, with complexity, aggression, and violence; fighting and fleeing actions can be injurious to patients as well as bed partners. Rapid eye movement sleep behavior disorder is distinguished from other parasomnias by clinical features and the demonstration of rapid eye movement sleep without atonia on polysomnography. Consistent with early neurodegeneration, patients with RBD demonstrate subtle motor, cognitive, and autonomic impairments. Approximately 50% of patients with spontaneous RBD will convert to a parkinsonian disorder within a decade. Ultimately, nearly all (81%-90%) patients with RBD develop a neurodegenerative disorder. Among patients with Parkinson disease, RBD predicts a non-tremor-predominant subtype, gait freezing, and an aggressive clinical course. The most commonly cited RBD treatments include low-dose clonazepam or high-dose melatonin taken orally at bedtime. Treatment of RBD can prevent injury to patients and bed partners. Because RBD is a prodromal syndrome of Parkinson disease (or related disorder), it represents a unique opportunity for developing and testing disease

  18. Learning course adjustments during arm movements with reversed sensitivity derivatives

    Directory of Open Access Journals (Sweden)

    Tweed Douglas B

    2010-11-01

    Full Text Available Abstract Background To learn, a motor system needs to know its sensitivity derivatives, which quantify how its neural commands affect motor error. But are these derivatives themselves learned, or are they known solely innately? Here we test a recent theory that the brain's estimates of sensitivity derivatives are revisable based on sensory feedback. In its simplest form, the theory says that each control system has a single, adjustable estimate of its sensitivity derivatives which affects all aspects of its task, e.g. if you learn to reach to mirror-reversed targets then your revised estimate should reverse not only your initial aiming but also your online course adjustments when the target jumps in mid-movement. Methods Human subjects bent a joystick to move a cursor to a target on a computer screen, but the cursor's motion was reversed relative to the joystick's. The target jumped once during each movement. Subjects had up to 4000 trials to practice aiming and responding to target jumps. Results All subjects learned to reverse both initial aiming and course adjustments. Conclusions Our study confirms that sensitivity derivatives can be relearned. It is consistent with the idea of a single, all-purpose estimate of those derivatives; and it suggests that the estimate is a function of context, as one would expect given that the true sensitivity derivatives may vary with the state of the controlled system, the target, and the motor commands.

  19. Load emphasizes muscle effort minimization during selection of arm movement direction.

    Science.gov (United States)

    Wang, Wanyue; Dounskaia, Natalia

    2012-10-04

    Directional preferences during center-out horizontal shoulder-elbow movements were previously established for both the dominant and non-dominant arm with the use of a free-stroke drawing task that required random selection of movement directions. While the preferred directions were mirror-symmetrical in both arms, they were attributed to a tendency specific for the dominant arm to simplify control of interaction torque by actively accelerating one joint and producing largely passive motion at the other joint. No conclusive evidence has been obtained in support of muscle effort minimization as a contributing factor to the directional preferences. Here, we tested whether distal load changes directional preferences, making the influence of muscle effort minimization on the selection of movement direction more apparent. The free-stroke drawing task was performed by the dominant and non-dominant arm with no load and with 0.454 kg load at the wrist. Motion of each arm was limited to rotation of the shoulder and elbow in the horizontal plane. Directional histograms of strokes produced by the fingertip were calculated to assess directional preferences in each arm and load condition. Possible causes for directional preferences were further investigated by studying optimization across directions of a number of cost functions. Preferences in both arms to move in the diagonal directions were revealed. The previously suggested tendency to actively accelerate one joint and produce passive motion at the other joint was supported in both arms and load conditions. However, the load increased the tendency to produce strokes in the transverse diagonal directions (perpendicular to the forearm orientation) in both arms. Increases in required muscle effort caused by the load suggested that the higher frequency of movements in the transverse directions represented increased influence of muscle effort minimization on the selection of movement direction. This interpretation was supported

  20. Expression of emotions in dance: relation between arm movement characteristics and emotion.

    Science.gov (United States)

    Sawada, Misako; Suda, Kazuhiro; Ishii, Motonobu

    2003-12-01

    This study was designed to investigate the relations between emotional expression and the movement characteristics. For this purpose, we used kinematic data related to three factors of the movement characteristics: Speed, Force, and Directness. In Exp. 1, we examined how the dancers expressed emotions when they used a certain body action and body part, and how they altered the movement characteristics. In Exp. 1, 10 female dancers were instructed to express three emotions, joy, sadness, and anger, by altering arm-movement characteristics. Analysis of variance indicated that the three exhibited emotional expressions had different movement characteristics. Discriminant analysis indicated that kinematic data for evaluation of movement characteristics are useful for discrimination of the three emotional expressions in dance. In Exp. 2, we investigated how naive observers perceived the type of emotion from the arm-movement characteristics. Analysis of variance showed that 22 observers accurately perceived each emotion distinguished from other emotions. Multiple regression analysis showed that specific movement characteristics influenced the perception of particular emotion.

  1. Effective propulsion in swimming : Grasping the hydrodynamics of hand and arm movements

    NARCIS (Netherlands)

    Van Houwelingen, Josje; Schreven, Sander; Smeets, Jeroen B J; Clercx, Herman J H; Beek, Peter J.

    2017-01-01

    In this paper, a literature review is presented regarding the hydrodynamic effects of different hand and arm movements during swimming with the aim to identify lacunae in current methods and knowledge, and to distil practical guidelines for coaches and swimmers seeking to increase swimming speed.

  2. Different temporal bases for body and arm movements in volleyball serve reception.

    Science.gov (United States)

    Benerink, N H; Bootsma, R J; Zaal, F T J M

    2015-10-01

    In many sports, successfully intercepting a ball requires players to move both their body and their arms. Yet, studies of interception typically focus on one or the other. We performed an analysis of the moments of first foot and arm movements of elite-level volleyball players during serve reception. Video footage of five international matches of the Netherlands men's national volleyball team allowed the systematic coding and analysis of 347 different serve reception events. For each event, we identified the time of serve (TS) and time of contact (TC). Ball flight time (from TS to TC) varied between and within types of serve (power jump serves, n = 193, and jumping float serves, n = 154). Correlation analyses revealed that foot movement was initiated with respect to time from TS, while arm movement was initiated with respect to time until TC. These results suggest that whole-body and arm movements rely on different control processes. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Arm and Hand Movement in Children Suspected of Having Autism Spectrum Disorder

    Science.gov (United States)

    Braddock, Barbara A.; Hilton, Jane C.

    2016-01-01

    The aim of this study was to describe arm and hand movement in children suspected of having autism spectrum disorder (ASD; age range 29-43 months). A videotaped retrospective review of five children with symptoms of ASD during "Communication Temptation Tasks" was completed at two time points (pre-testing and 6 weeks later). Categories of…

  4. Neuromechanical considerations for incorporating rhythmic arm movement in the rehabilitation of walking

    Science.gov (United States)

    Klimstra, Marc D.; Thomas, Evan; Stoloff, Rebecca H.; Ferris, Daniel P.; Zehr, E. Paul

    2009-06-01

    We have extensively used arm cycling to study the neural control of rhythmic movements such as arm swing during walking. Recently rhythmic movement of the arms has also been shown to enhance and shape muscle activity in the legs. However, restricted information is available concerning the conditions necessary to maximally alter lumbar spinal cord excitability. Knowledge on the neuromechanics of a task can assist in the determination of the type, level, and timing of neural signals, yet arm swing during walking and arm cycling have not received a detailed neuromechanical comparison. The purpose of this research was to provide a combined neural and mechanical measurement approach that could be used to assist in the determination of the necessary and sufficient conditions for arm movement to assist in lower limb rehabilitation after stroke and spinal cord injury. Subjects performed three rhythmic arm movement tasks: (1) cycling (cycle); (2) swinging while standing (swing); and (3) swinging while treadmill walking (walk). We hypothesized that any difference in neural control between tasks (i.e., pattern of muscle activity) would reflect changes in the mechanical constraints unique to each task. Three-dimensional kinematics were collected simultaneously with force measurement at the hand and electromyography from the arms and trunk. All data were appropriately segmented to allow a comparison between and across conditions and were normalized and averaged to 100% movement cycle based on shoulder excursion. Separate mathematical principal components analysis of kinematic and neural variables was performed to determine common task features and muscle synergies. The results highlight important neural and mechanical features that distinguish differences between tasks. For example, there are considerable differences in the anatomical positions of the arms during each task, which relate to the moments experienced about the elbow and shoulder. Also, there are differences between

  5. Detecting rapid mass movements using electrical self-potential measurements

    Science.gov (United States)

    Heinze, Thomas; Limbrock, Jonas; Pudasaini, Shiva P.; Kemna, Andreas

    2017-04-01

    Rapid mass movements are a latent danger for lives and infrastructure in almost any part of the world. Often such mass movements are caused by increasing pore pressure, for example, landslides after heavy rainfall or dam breaking after intrusion of water in the dam. Among several other geophysical methods used to observe water movement, the electrical self-potential method has been applied to a broad range of monitoring studies, especially focusing on volcanism and dam leakage but also during hydraulic fracturing and for earthquake prediction. Electrical self-potential signals may be caused by various mechanisms. Though, the most relevant source of the self-potential field in the given context is the streaming potential, caused by a flowing electrolyte through porous media with electrically charged internal surfaces. So far, existing models focus on monitoring water flow in non-deformable porous media. However, as the self-potential is sensitive to hydraulic parameters of the soil, any change in these parameters will cause an alteration of the electric signal. Mass movement will significantly influence the hydraulic parameters of the solid as well as the pressure field, assuming that fluid movement is faster than the pressure diffusion. We will present results of laboratory experiments under drained and undrained conditions with fluid triggered as well as manually triggered mass movements, monitored with self-potential measurements. For the undrained scenarios, we observe a clear correlation between the mass movements and signals in the electric potential, which clearly differ from the underlying potential variations due to increased saturation and fluid flow. In the drained experiments, we do not observe any measurable change in the electric potential. We therefore assume that change in fluid properties and release of the load causes disturbances in flow and streaming potential. We will discuss results of numerical simulations reproducing the observed effect. Our

  6. Genetics of rapid eye movement sleep in humans

    OpenAIRE

    Adamczyk, M.; Ambrosius, U; Lietzenmaier, S; Wichniak, A; Holsboer, F.; Friess, E

    2015-01-01

    The trait-like nature of electroencephalogram (EEG) is well established. Furthermore, EEG of wake and non-rapid eye movement (non-REM) sleep has been shown to be highly heritable. However, the genetic effects on REM sleep EEG microstructure are as yet unknown. REM sleep is of special interest since animal and human data suggest a connection between REM sleep abnormalities and the pathophysiology of psychiatric and neurological diseases. Here we report the results of a study in monozygotic (MZ...

  7. Moving Events in Time: Time-Referent Hand-Arm Movements Influence Perceived Temporal Distance to Past Events

    Science.gov (United States)

    Blom, Stephanie S. A. H.; Semin, Gun R.

    2013-01-01

    We examine and find support for the hypothesis that time-referent hand-arm movements influence temporal judgments. In line with the concept of "left is associated with earlier times, and right is associated with later times," we show that performing left (right) hand-arm movements while thinking about a past event increases (decreases) the…

  8. Arm Orthosis/Prosthesis Movement Control Based on Surface EMG Signal Extraction.

    Science.gov (United States)

    Suberbiola, Aaron; Zulueta, Ekaitz; Lopez-Guede, Jose Manuel; Etxeberria-Agiriano, Ismael; Graña, Manuel

    2015-05-01

    This paper shows experimental results on electromyography (EMG)-based system control applied to motorized orthoses. Biceps and triceps EMG signals are captured through two biometrical sensors, which are then filtered and processed by an acquisition system. Finally an output/control signal is produced and sent to the actuators, which will then perform the actual movement, using algorithms based on autoregressive (AR) models and neural networks, among others. The research goal is to predict the desired movement of the lower arm through the analysis of EMG signals, so that the movement can be reproduced by an arm orthosis, powered by two linear actuators. In this experiment, best accuracy has achieved values up to 91%, using a fourth-order AR-model and 100ms block length.

  9. Importance of Rapid Eye Movement Sleep Behavior Disorder to the Primary Care Physician.

    Science.gov (United States)

    McCarter, Stuart J; Howell, Michael J

    2016-10-01

    Sleep disorders and neurodegenerative diseases are commonly encountered in primary care. A common, but underdiagnosed sleep disorder, rapid eye movement sleep behavior disorder (RBD), is highly associated with Parkinson disease and related disorders. Rapid eye movement sleep behavior disorder is common. It is estimated to affect 0.5% of the general population and more than 7% of individuals older than 60 years; however, most cases go unrecognized. Rapid eye movement sleep behavior disorder presents as dream enactment, often with patients thrashing, punching, and kicking while they are sleeping. Physicians can quickly assess for the presence of RBD with high sensitivity and specificity by asking patients the question "Have you ever been told that you act out your dreams, for example by punching or flailing your arms in the air or screaming and shouting in your sleep?" Patients with RBD exhibit subtle signs of neurodegenerative disease, such as mild motor slowing, constipation, or changes in sense of smell. These signs and symptoms may predict development of a neurodegenerative disease within 3 years. Ultimately, most patients with RBD develop a neurodegenerative disease, highlighting the importance of serial neurological examinations to assess for the presence of parkinsonism and/or cognitive impairment and prognostic counseling for these patients. Rapid eye movement sleep behavior disorder is treatable with melatonin (3-6 mg before bed) or clonazepam (0.5-1 mg before bed) and may be the most common, reversible cause of sleep-related injury. Thus, it is important to identify patients at risk of RBD in a primary care setting so that bedroom safety can be addressed and treatment may be initiated. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  10. A flow visualization study of single-arm sculling movement emulating cephalopod thrust generation

    Science.gov (United States)

    Kazakidi, Asimina; Gnanamanickam, Ebenezer P.; Tsakiris, Dimitris P.; Ekaterinaris, John A.

    2014-11-01

    In addition to jet propulsion, octopuses use arm-swimming motion as an effective means of generating bursts of thrust, for hunting, defense, or escape. The individual role of their arms, acting as thrust generators during this motion, is still under investigation, in view of an increasing robotic interest for alternative modes of propulsion, inspired by the octopus. Computational studies have revealed that thrust generation is associated with complex vortical flow patterns in the wake of the moving arm, however further experimental validation is required. Using the hydrogen bubble technique, we studied the flow disturbance around a single octopus-like robotic arm, undergoing two-stroke sculling movements in quiescent fluid. Although simplified, sculling profiles have been found to adequately capture the fundamental kinematics of the octopus arm-swimming behavior. In fact, variation of the sculling parameters alters considerably the generation of forward thrust. Flow visualization revealed the generation of complex vortical structures around both rigid and compliant arms. Increased disturbance was evident near the tip, particularly at the transitional phase between recovery and power strokes. These results are in good qualitative agreement with computational and robotic studies. Work funded by the ESF-GSRT HYDRO-ROB Project PE7(281).

  11. Rapid Detection of Small Movements with GNSS Doppler Observables

    Science.gov (United States)

    Hohensinn, Roland; Geiger, Alain

    2017-04-01

    High-alpine terrain reacts very sensitively to varying environmental conditions. As an example, increasing temperatures cause thawing of permafrost areas. This, in turn causes an increasing threat by natural hazards like debris flow (e.g. rock glaciers) or rockfalls. The Institute of Geodesy and Photogrammetry is contributing to alpine mass-movement monitoring systems in different project areas in the Swiss Alps. A main focus lies on providing geodetic mass-movement information derived from GNSS static solutions on a daily and a sub-daily basis, obtained with low-cost and autonomous GNSS stations. Another focus is set on rapidly providing reliable geodetic information in real-time i.e. for an integration in early warning systems. One way to achieve this is the estimation of accurate station velocities from observations of range rates, which can be obtained as Doppler observables from time derivatives of carrier phase measurements. The key for this method lies in a precise modeling of prominent effects contributing to the observed range rates, which are satellite velocity, atmospheric delay rates and relativistic effects. A suitable observation model is then devised, which accounts for these predictions. The observation model, combined with a simple kinematic movement model forms the basis for the parameter estimation. Based on the estimated station velocities, movements are then detected using a statistical test. To improve the reliablity of the estimated parameters, another spotlight is set on an on-line quality control procedure. We will present the basic algorithms as well as results from first tests which were carried out with a low-cost GPS L1 phase receiver. With a u-blox module and a sampling rate of 5 Hz, accuracies on the mm/s level can be obtained and velocities down to 1 cm/s can be detected. Reliable and accurate station velocities and movement information can be provided within seconds.

  12. Morbidities in rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Jennum, Poul; Mayer, Geert; Ju, Yo-El

    2013-01-01

    Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD, RBD without any obvious comorbid major neurological disease), is strongly associated with numerous comorbid conditions. The most prominent is that with neurodegenerative disorders, especially synuclein-mediated disorders, above all...... of dementia with Lewy bodies. These findings underline the progressive disease process, suggesting involvement of more brain regions in patients with a more advanced disease stage. RBD is also associated with narcolepsy, and it is likely that RBD associated with narcolepsy is a distinct subtype associated...

  13. Artificially Controlling the Limb Movement of Robotic Arm Using Machine Interface with EMG Sensor

    Directory of Open Access Journals (Sweden)

    Govind Singh PATEL

    2008-03-01

    Full Text Available The aim of this paper is described a human machine interface using Electromyogram signal to artificially control the limb movement usually called fictional Electrical Stimulation and Rehabilitation. Functional electrical stimulation (FES is used widely in rehabilitation to restore motor functions for paralyzed patients. Each muscle fiber has a potential and motor unit action potential generated by construction of muscle is studied and corresponding actuation is provided to robotics arm.

  14. On Control of Reaching Movements for Musculo-Skeletal Redundant Arm Model

    Directory of Open Access Journals (Sweden)

    Kenji Tahara

    2009-01-01

    Full Text Available This paper focuses on a dynamic sensory-motor control mechanism of reaching movements for a musculo-skeletal redundant arm model. The formulation of a musculo-skeletal redundant arm system, which takes into account non-linear muscle properties obtained by some physiological understandings, is introduced and numerical simulations are perfomed. The non-linear properties of muscle dynamics make it possible to modulate the viscosity of the joints, and the end point of the arm converges to the desired point with a simple task-space feedback when adequate internal forces are chosen, regardless of the redundancy of the joint. Numerical simulations were performed and the effectiveness of our control scheme is discussed through these results. The results suggest that the reaching movements can be achieved using only a simple task-space feedback scheme together with the internal force effect that comes from non-linear properties of skeletal muscles without any complex mathematical computation such as an inverse dynamics or optimal trajectory derivation. In addition, the dynamic damping ellipsoid for evaluating how the internal forces can be determined is introduced. The task-space feedback is extended to the ‘virtual spring-damper hypothesis’ based on the research by Arimoto et al. (2006 to reduce the muscle output forces and heterogeneity of convergence depending on the initial state and desired position. The research suggests a new direction for studies of brain-motor control mechanism of human movements.

  15. Arm movement maps evoked by cortical magnetic stimulation in a robotic environment.

    Science.gov (United States)

    Jones-Lush, L M; Judkins, T N; Wittenberg, G F

    2010-02-03

    Many neurological diseases result in a severe inability to reach for which there is no proven therapy. Promising new interventions to address reaching rehabilitation using robotic training devices are currently under investigation in clinical trials but the neural mechanisms that underlie these interventions are not understood. Transcranial magnetic stimulation (TMS) may be used to probe such mechanisms quickly and non-invasively, by mapping muscle and movement representations in the primary motor cortex (M1). Here we investigate movement maps in healthy young subjects at rest using TMS in the robotic environment, with the goal of determining the range of TMS accessible movements, as a starting point for the study of cortical plasticity in combination with robotic therapy. We systematically stimulated the left motor cortex of 14 normal volunteers while the right hand and forearm rested in the cradle of a two degree-of-freedom planar rehabilitation robot (IMT). Maps were created by applying 10 stimuli at each of nine locations (3x3 cm(2) grid) centered on the M1 movement hotspot for each subject, defined as the stimulation location that elicited robot cradle movements of the greatest distance. TMS-evoked movement kinematics were measured by the robotic encoders and ranged in magnitude from 0 to 3 cm. Movement maps varied by subject and by location within a subject. However, movements were very consistent within a single stimulation location for a given subject. Movement vectors remained relatively constant (limited to arm movements in the robotic reaching trainer, and thus may provide a real-time, non-invasive platform for neurophysiology based evaluation and therapy in motor rehabilitation settings. Published by Elsevier Ltd.

  16. Lycra(®) arm splints improve movement fluency in children with cerebral palsy.

    Science.gov (United States)

    Elliott, Catherine; Reid, Siobhan; Hamer, Peter; Alderson, Jacqueline; Elliott, Bruce

    2011-02-01

    To determine changes in upper limb movement substructures that denote fluency of movement in children with cerebral palsy (CP) following lycra(®) splint wear. Secondarily, to explore the efficacy of lycra(®) splints for those with spastic and dystonic hypertonia. Randomised clinical trial whereby participants were randomised to parallel groups with waiting list control. Sixteen children (mean age 11.5 years SD=2.2) with hypertonic upper limb involvement (13 hemiplegia, 4 quadriplegia) were recruited. Children were randomly allocated either to a control group or to wear the lycra(®) splint for a period of three months. Three-dimensional (3D) upper limb kinematics was used to assess four functional tasks at baseline, on initial lycra(®) splint application, three months after lycra(®) splint wear, and immediately after splint removal. Movement substructures of the motion of the wrist joint center were analysed. A significant difference was observed between baseline and three months of lycra(®) splint wear in the movement substructures; movement time, percentage of time and distance in primary movement, jerk index, normalised jerk and percentage of jerk in primary and secondary movements. The magnitude of changes in normalised jerk and the percentage of jerk in the primary movement from baseline to three months was greatest in children with dystonic hypertonia. The results indicate that lycra(®) arm splinting induced significant changes in movement substructures and motor performance in children with CP. This research demonstrates that fluency of movement can be quantified and is amenable to change with intervention. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

  17. The improvement of movement and speech during rapid eye movement sleep behaviour disorder in multiple system atrophy.

    Science.gov (United States)

    De Cock, Valérie Cochen; Debs, Rachel; Oudiette, Delphine; Leu, Smaranda; Radji, Fatai; Tiberge, Michel; Yu, Huan; Bayard, Sophie; Roze, Emmanuel; Vidailhet, Marie; Dauvilliers, Yves; Rascol, Olivier; Arnulf, Isabelle

    2011-03-01

    Multiple system atrophy is an atypical parkinsonism characterized by severe motor disabilities that are poorly levodopa responsive. Most patients develop rapid eye movement sleep behaviour disorder. Because parkinsonism is absent during rapid eye movement sleep behaviour disorder in patients with Parkinson's disease, we studied the movements of patients with multiple system atrophy during rapid eye movement sleep. Forty-nine non-demented patients with multiple system atrophy and 49 patients with idiopathic Parkinson's disease were interviewed along with their 98 bed partners using a structured questionnaire. They rated the quality of movements, vocal and facial expressions during rapid eye movement sleep behaviour disorder as better than, equal to or worse than the same activities in an awake state. Sleep and movements were monitored using video-polysomnography in 22/49 patients with multiple system atrophy and in 19/49 patients with Parkinson's disease. These recordings were analysed for the presence of parkinsonism and cerebellar syndrome during rapid eye movement sleep movements. Clinical rapid eye movement sleep behaviour disorder was observed in 43/49 (88%) patients with multiple system atrophy. Reports from the 31/43 bed partners who were able to evaluate movements during sleep indicate that 81% of the patients showed some form of improvement during rapid eye movement sleep behaviour disorder. These included improved movement (73% of patients: faster, 67%; stronger, 52%; and smoother, 26%), improved speech (59% of patients: louder, 55%; more intelligible, 17%; and better articulated, 36%) and normalized facial expression (50% of patients). The rate of improvement was higher in Parkinson's disease than in multiple system atrophy, but no further difference was observed between the two forms of multiple system atrophy (predominant parkinsonism versus cerebellar syndrome). Video-monitored movements during rapid eye movement sleep in patients with multiple system

  18. Modeling rapid mass movements using the shallow water equations

    Science.gov (United States)

    Hergarten, S.; Robl, J.

    2014-11-01

    We propose a new method to model rapid mass movements on complex topography using the shallow water equations in Cartesian coordinates. These equations are the widely used standard approximation for the flow of water in rivers and shallow lakes, but the main prerequisite for their application - an almost horizontal fluid table - is in general not satisfied for avalanches and debris flows in steep terrain. Therefore, we have developed appropriate correction terms for large topographic gradients. In this study we present the mathematical formulation of these correction terms and their implementation in the open source flow solver GERRIS. This novel approach is evaluated by simulating avalanches on synthetic and finally natural topographies and the widely used Voellmy flow resistance law. The results are tested against analytical solutions and the commercial avalanche model RAMMS. The overall results are in excellent agreement with the reference system RAMMS, and the deviations between the different models are far below the uncertainties in the determination of the relevant fluid parameters and involved avalanche volumes in reality. As this code is freely available and open source, it can be easily extended by additional fluid models or source areas, making this model suitable for simulating several types of rapid mass movements. It therefore provides a valuable tool assisting regional scale natural hazard studies.

  19. Sensorimotor Reorganizations of Arm Kinematics and Postural Strategy for Functional Whole-Body Reaching Movements in Microgravity

    Directory of Open Access Journals (Sweden)

    Thomas Macaluso

    2017-10-01

    Full Text Available Understanding the impact of weightlessness on human behavior during the forthcoming long-term space missions is of critical importance, especially when considering the efficiency of goal-directed movements in these unusual environments. Several studies provided a large set of evidence that gravity is taken into account during the planning stage of arm reaching movements to optimally anticipate its consequence upon the moving limbs. However, less is known about sensorimotor changes required to face weightless environments when individuals have to perform fast and accurate goal-directed actions with whole-body displacement. We thus aimed at characterizing kinematic features of whole-body reaching movements in microgravity, involving high spatiotemporal constraints of execution, to question whether and how humans are able to maintain the performance of a functional behavior in the standards of normogravity execution. Seven participants were asked to reach as fast and as accurately as possible visual targets while standing during microgravity episodes in parabolic flight. Small and large targets were presented either close or far from the participants (requiring, in the latter case, additional whole-body displacement. Results reported that participants successfully performed the reaching task with general temporal features of movement (e.g., movement speed close to land observations. However, our analyses also demonstrated substantial kinematic changes related to the temporal structure of focal movement and the postural strategy to successfully perform -constrained- whole-body reaching movements in microgravity. These immediate reorganizations are likely achieved by rapidly taking into account the absence of gravity in motor preparation and execution (presumably from cues about body limbs unweighting. Specifically, when compared to normogravity, the arm deceleration phase substantially increased. Furthermore, greater whole-body forward displacements

  20. Modifying the Functional Movement Screen Deep Squat Test: The Effect of Foot and Arm Positional Variations.

    Science.gov (United States)

    McMillian, Danny J; Rynders, Zach G; Trudeau, Tyler R

    2016-04-01

    The functional movement screen (FMS) was developed as an evaluation tool for assessing the fundamental movement patterns believed to be prerequisites for functional activity. However, some of the FMS component movements, such as the deep overhead squat test (DST), likely represent novel motor challenges on which poor performance might reflect inexperience with the task rather than a movement impairment. The purpose of this study was to examine the effects of positional variations on DST scores in a population of young, healthy adults. We hypothesized that self-selecting foot positioning, removal of an overhead component, or changing both aspects of the DST would result in improvement in FMS scores. Twenty healthy subjects completed 4 squatting conditions in a counterbalanced sequence to eliminate carry over effects: DST, modified squat with hands at chest level and feet in the DST position (DSTO), modified squat with arms in the DST position and self-selected foot placement (DSTF), and modified squat with hands at chest level and self-selected foot placement (DSTB). A Friedman's analysis of variance and Wilcoxon signed-ranks' post hoc analysis revealed a significant difference between all squat conditions (p = 0.036), between DSTB-DST groups (p functional tasks that involve self-selected foot and arm placement.

  1. Movement analysis of upper limb during resistance training using general purpose robot arm "PA10"

    Science.gov (United States)

    Morita, Yoshifumi; Yamamoto, Takashi; Suzuki, Takahiro; Hirose, Akinori; Ukai, Hiroyuki; Matsui, Nobuyuki

    2005-12-01

    In this paper we perform movement analysis of an upper limb during resistance training. We selected sanding training, which is one type of resistance training for upper limbs widely performed in occupational therapy. Our final aims in the future are to quantitatively evaluate the therapeutic effect of upper limb motor function during training and to develop a new rehabilitation training support system. For these purposes, first of all we perform movement analysis using a conventional training tool. By measuring upper limb motion during the sanding training we perform feature abstraction. Next we perform movement analysis using the simulated sanding training system. This system is constructed using the general purpose robot arm "PA10". This system enables us to measure the force/torque exerted by subjects and to easily change the load of resistance. The control algorithm is based on impedance control. We found these features of the upper limb motion during the sanding training.

  2. Context-dependent adaptation of visually-guided arm movements and vestibular eye movements: role of the cerebellum

    Science.gov (United States)

    Lewis, Richard F.

    2003-01-01

    Accurate motor control requires adaptive processes that correct for gradual and rapid perturbations in the properties of the controlled object. The ability to quickly switch between different movement synergies using sensory cues, referred to as context-dependent adaptation, is a subject of considerable interest at present. The potential function of the cerebellum in context-dependent adaptation remains uncertain, but the data reviewed below suggest that it may play a fundamental role in this process.

  3. The effects of arm movement on reaction time in patients with latent and active upper trapezius myofascial trigger point

    National Research Council Canada - National Science Library

    Yassin, Marzieh; Talebian, Saeed; Ebrahimi Takamjani, Ismail; Maroufi, Nader; Ahmadi, Amir; Sarrafzadeh, Javad; Emrani, Anita

    2015-01-01

    Myofascial pain syndrome is a significant source of mechanical pain. The aim of this study was to investigate the effects of arm movement on reaction time in females with latent and active upper trapezius myofascial trigger point...

  4. Rapid eye movement sleep behaviour disorder in patients with narcolepsy is associated with hypocretin-1 deficiency

    DEFF Research Database (Denmark)

    Knudsen, Stine; Gammeltoft, Steen; Jennum, Poul J

    2010-01-01

    that rapid eye movement sleep behaviour disorder coexists with cataplexy in narcolepsy due to hypocretin deficiency. In our study, rapid eye movement sleep behaviour disorder was diagnosed by the International Classification of Sleep Disorders (2nd edition) criteria in 63 narcolepsy patients with or without......Rapid eye movement sleep behaviour disorder is characterized by dream-enacting behaviour and impaired motor inhibition during rapid eye movement sleep. Rapid eye movement sleep behaviour disorder is commonly associated with neurodegenerative disorders, but also reported in narcolepsy with cataplexy....... Most narcolepsy with cataplexy patients lack the sleep-wake, and rapid eye movement sleep, motor-regulating hypocretin neurons in the lateral hypothalamus. In contrast, rapid eye movement sleep behaviour disorder and hypocretin deficiency are rare in narcolepsy without cataplexy. We hypothesized...

  5. The effects of spinal mobilization with arm movements on shoulder muscle strengthening.

    Science.gov (United States)

    Seo, Youngjoon; Lee, Jaeseok; Han, Dongwook

    2015-01-01

    [Purpose] This study was performed to examine the immediate effects of spinal mobilization with arm movements (SMWAMs) for strengthening the shoulder muscles. [Subjects] The subjects of this study were 12 healthy male students who were studying at S University, Busan City. They had no musculoskeletal disease, or upper congenital malformation, and had no history of surgery or neurological disease. [Methods] The SMWAMs were performed on the 4th cervical vertebra (C4). For stimulation of the 5th cervical nerve, the spinous process of the C4 was pushed to the left and held in place. Then the arm was abducted to the point where spinous process was felt, and the range of abduction was examined. Subsequently, the abduction movement was repeated 10 times to the same point, and the gliding of C4 was held until the arm returned to the starting position. During the treatment, the head and the trunk were held in the correct posture. [Results] After SMWAMs had been performed, the muscular strength of shoulder flexion, extension and adduction significantly increased. [Conclusion] In our opinion, the SMWAMs are a very useful method for correcting spinal malalignment, and for stimulating the joint mechanoreceptors without the risks of manipulation. SMWAM is a valuable therapy method that can complement the demerits of mobilization.

  6. Intrinsic joint kinematic planning. I: Reassessing the Listing's law constraint in the control of three-dimensional arm movements.

    NARCIS (Netherlands)

    Liebermann, D.G.; Biess, A.; Friedman, J.; Gielen, C.C.A.M.; Flash, T.

    2006-01-01

    This study tested the validity of the assumption that intrinsic kinematic constraints, such as Listing's law, can account for the geometric features of three-dimensional arm movements. In principle, if the arm joints follow a Listing's constraint, the hand paths may be predicted. Four individuals

  7. [Parkinson Disease With Rapid Eye Movement Sleep Behavior Disorder].

    Science.gov (United States)

    Hu, Yang; Zhang, Wei

    2015-06-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by lack of muscle atonia during REM sleep and enactment of dream content. RBD is associated with Parkinson disease (PD) and has high incidence in PD patients. PD patient with RBD mainly presents rigid type, has longer disease duration, more severe motor and non-motor symptoms and poorer activity of daily living and life quality. The pathophysiological mechanisms of RBD may be related to dysfunctions of pontine tegmentum, locus coeruleus/sub-locus coeruleus complex and related projections. The diagnosis of RBD depends on clinical histories and video-polysomnography (v-PSG). Besides treatment for PD, protective measures have to be taken for patients and their sleep partners. If abnormal behaviors during sleep cause distress and danger,patients should be given drug therapy.

  8. Cognition in rapid eye movement sleep behavior disorder

    Directory of Open Access Journals (Sweden)

    Jean-François eGagnon

    2012-05-01

    Full Text Available Rapid eye movement (REM sleep behavior disorder (RBD is a parasomnia characterized by excessive muscle activity and undesirable motor events during REM sleep. RBD occurs in approximately 0.5% of the general population, with a higher prevalence in older men. RBD is a frequent feature of dementia with Lewy bodies (DLB, but is only rarely reported in Alzheimer’s disease. RBD is also a risk factor for α-synuclein-related diseases, such as DLB, Parkinson’s disease (PD, and multiple system atrophy. Therefore, RBD has major implications for the diagnosis and treatment of neurodegenerative disorders and for understanding neurodegeneration mechanisms. Several markers of neurodegeneration have been identified in RBD, including cognitive impairments such as deficits in attention, executive functions, learning capacities, and visuospatial abilities. Approximately 50% of RBD patients present mild cognitive impairment (MCI. Moreover, RBD is also associated with cognitive decline in PD.

  9. Detection of rapid-eye movements in sleep studies.

    Science.gov (United States)

    Agarwal, Rajeev; Takeuchi, Tomoka; Laroche, Suzie; Gotman, Jean

    2005-08-01

    One of the key features of rapid-eye movement (REM) sleep is the presence of bursts of REMs. Sleep studies routinely use REMs to classify sleep stages. Moreover, REM count or density has been used in studies involving learning and various psychiatric disorders. Most of these studies have been based on the visual identification of REMs, which is generally a very time-consuming task. This and the varying definitions of REMs across scorers have warranted the development of automatic REM detection methodologies. In this paper, we present a new detection scheme that combines many of the intrinsic properties of REMs and requires minimal parameter adjustments. In the proposed method, a single parameter can be used to control the REM detection sensitivity and specificity tradeoff. Manually scored training data are used to develop the method. We assess the performance of the method against manual scoring of individual REM events and present validation results using a separate data set. The ability of the method to discriminate fast horizontal ocular movement in REM sleep from other types of events is highlighted. A key advantage of the presented method is the minimal a priori information requirement. The results of training data (recordings from five subjects) show an overall sensitivity of 78.8% and specificity of 81.6%. The performance on the testing data (recording from five subjects different from the training data) showed overall sensitivity of 67.2% and specificity of 77.5%.

  10. Adaptive patterns of movement during arm elevation test in patients with shoulder impingement syndrome.

    Science.gov (United States)

    Lin, Jiu-jenq; Hsieh, Shih-Chang; Cheng, Wei-Cheng; Chen, Wei Chun; Lai, Yuta

    2011-05-01

    The purpose of this study was to determine if a distinctive characteristic exists in the pattern of movement (scapular elevation and upward rotation to reduce impingement) and associated muscular activities during arm elevation in subjects with shoulder impingement (SI) that is associated with the severity of the disease. Fourteen subjects (7 amateur athletes and 7 student athletes) with SI and 7 controls performed arm elevation in the scapular plane. Scapular kinematics (upward rotation, elevation, tipping, and scapulohumeral rhythm) and muscular activity [upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and deltoid] were measured by an electromagnetic motion tracking system and surface electromyography, respectively. Subjects with SI had greater elevation of the scapula (11.9 mm, p < 0.005) and less peak scapular posterior tipping (10.6°, p < 0.02) than controls. In more severe subjects (amateur athletes), the elevation and posterior tipping of the scapula were correlated with an increase in the UT (R = -0.818, p = 0.025) and a decrease in SA (R = 0.772, p = 0.040) activity, respectively. Our results identified a characteristic compensatory scapular elevation to reduce impingement during arm elevation in subjects with SI. Assessing scapular elevation during arm elevation may be a useful functional marker for evaluating impingement status and associated muscle function. Additionally, SA and LT muscle strengthening may improve SI. Copyright © 2010 Orthopaedic Research Society.

  11. Soft Neurological Signs in Childhood by Measurement of Arm Movements Using Acceleration and Angular Velocity Sensors

    Directory of Open Access Journals (Sweden)

    Miki Kaneko

    2015-10-01

    Full Text Available Soft neurological signs (SNS are evident in the motor performance of children and disappear as the child grows up. Therefore SNS are used as criteria for evaluating age-appropriate development of neurological function. The aim of this study was to quantify SNS during arm movement in childhood. In this study, we focused on pronation and supination, which are arm movements included in the SNS examination. Two hundred and twenty-three typically developing children aged 4–12 years (107 boys, 116 girls and 18 adults aged 21–26 years (16 males, two females participated in the experiment. To quantify SNS during pronation and supination, we calculated several evaluation index scores: bimanual symmetry, compliance, postural stability, motor speed and mirror movement. These index scores were evaluated using data obtained from sensors attached to the participants’ hands and elbows. Each score increased as age increased. Results obtained using our system showed developmental changes that were consistent with criteria for SNS. We were able to successfully quantify SNS during pronation and supination. These results indicate that it may be possible to use our system as quantitative criteria for evaluating development of neurological function.

  12. A hybrid BMI-based exoskeleton for paresis: EMG control for assisting arm movements

    Science.gov (United States)

    Kawase, Toshihiro; Sakurada, Takeshi; Koike, Yasuharu; Kansaku, Kenji

    2017-02-01

    Objective. Brain-machine interface (BMI) technologies have succeeded in controlling robotic exoskeletons, enabling some paralyzed people to control their own arms and hands. We have developed an exoskeleton asynchronously controlled by EEG signals. In this study, to enable real-time control of the exoskeleton for paresis, we developed a hybrid system with EEG and EMG signals, and the EMG signals were used to estimate its joint angles. Approach. Eleven able-bodied subjects and two patients with upper cervical spinal cord injuries (SCIs) performed hand and arm movements, and the angles of the metacarpophalangeal (MP) joint of the index finger, wrist, and elbow were estimated from EMG signals using a formula that we derived to calculate joint angles from EMG signals, based on a musculoskeletal model. The formula was exploited to control the elbow of the exoskeleton after automatic adjustments. Four able-bodied subjects and a patient with upper cervical SCI wore an exoskeleton controlled using EMG signals and were required to perform hand and arm movements to carry and release a ball. Main results. Estimated angles of the MP joints of index fingers, wrists, and elbows were correlated well with the measured angles in 11 able-bodied subjects (correlation coefficients were 0.81  ±  0.09, 0.85  ±  0.09, and 0.76  ±  0.13, respectively) and the patients (e.g. 0.91  ±  0.01 in the elbow of a patient). Four able-bodied subjects successfully positioned their arms to adequate angles by extending their elbows and a joint of the exoskeleton, with root-mean-square errors  hands using real-time control was realized by designing a new method to estimate joint angles based on EMG signals, and these may be useful for practical rehabilitation and the support of daily actions.

  13. Investigating rapid eye movement sleep without atonia in Parkinson's disease using the rapid eye movement sleep behavior disorder screening questionnaire.

    Science.gov (United States)

    Bolitho, Samuel J; Naismith, Sharon L; Terpening, Zoe; Grunstein, Ron R; Melehan, Kerri; Yee, Brendon J; Coeytaux, Alessandra; Gilat, Moran; Lewis, Simon J G

    2014-05-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is frequently observed in patients with Parkinson's disease (PD). Accurate diagnosis is essential for managing this condition. Furthermore, the emergence of idiopathic RBD in later life can represent a premotor feature, heralding the development of PD. Reliable, accurate methods for identifying RBD may offer a window for early intervention. This study sought to identify whether the RBD screening questionnaire (RBDSQ) and three questionnaires focused on dream enactment were able to correctly identify patients with REM without atonia (RWA), the neurophysiological hallmark of RBD. Forty-six patients with PD underwent neurological and sleep assessment in addition to completing the RBDSQ, the RBD single question (RBD1Q), and the Mayo Sleep Questionnaire (MSQ). The REM atonia index was derived for all participants as an objective measure of RWA. Patients identified to be RBD positive on the RBDSQ did not show increased RWA on polysomnography (80% sensitivity and 55% specificity). However, patients positive for RBD on questionnaires specific to dream enactment correctly identified higher degrees of RWA and improved the diagnostic accuracy of these questionnaires. This study suggests that the RBDSQ does not accurately identify RWA, essential for diagnosing RBD in PD. Furthermore, the results suggest that self-report measures of RBD need to focus questions on dream enactment behavior to better identify RWA and RBD. Further studies are needed to develop accurate determination and quantification of RWA in RBD to improve management of patients with PD in the future. © 2014 International Parkinson and Movement Disorder Society.

  14. Robot-assisted movement training for the stroke-impaired arm: Does it matter what the robot does?

    Science.gov (United States)

    Kahn, Leonard E; Lum, Peter S; Rymer, W Zev; Reinkensmeyer, David J

    2006-01-01

    Robot-assisted movement training improves arm movement ability following acute and chronic stroke. Such training involves two interacting processes: the patient trying to move and the robot applying forces to the patient's arm. A fundamental principle of motor learning is that movement practice improves motor function; the role of applied robotic forces in improving motor function is still unclear. This article reviews our work addressing this question. Our pilot study using the Assisted Rehabilitation and Measurement (ARM) Guide, a linear robotic trainer, found that mechanically assisted reaching improved motor recovery similar to unassisted reaching practice. This finding is inconclusive because of the small sample size (n = 19), but suggest that future studies should carefully control the amount of voluntary movement practice delivered to justify the use of robotic forces. We are optimistic that robotic forces will ultimately show additional therapeutic benefits when coupled with movement practice. We justify this optimism here by comparing results from the ARM Guide and the Mirror Image Movement Enabler robotic trainer. This comparison suggests that requiring a patient to generate specific patterns of force before allowing movement is more effective than mechanically completing movements for the patient. We describe the engineering implementation of this "guided-force training" algorithm.

  15. Active Bio-sensor System, Compatible with Arm Muscle Movement or Blinking Signals in BCI Application

    Directory of Open Access Journals (Sweden)

    Saeid Mehrkanoon

    2008-05-01

    Full Text Available This paper addresses a bionic active sensor system for the BCI application. Proposed system involves analog and digital parts. Two types of accurate sensors are used to pickup the blinking and muscle movement signals. A precision micro-power instrumentation amplifier with the adjustable gain, a sixth order low pass active filter with cutoff frequency 0.1 Hz, and a sixth order band pas filter with the bandwidth of 2-6 Hz are constructed to provide the clean blinking and arm muscle movement signals. TMS320C25 DSP processor is used for independent and unique command signals which are prepared for BCI application by a power amplifier and driver.

  16. Combined influence of visual scene and body tilt on arm pointing movements: gravity matters!

    Science.gov (United States)

    Scotto Di Cesare, Cécile; Sarlegna, Fabrice R; Bourdin, Christophe; Mestre, Daniel R; Bringoux, Lionel

    2014-01-01

    Performing accurate actions such as goal-directed arm movements requires taking into account visual and body orientation cues to localize the target in space and produce appropriate reaching motor commands. We experimentally tilted the body and/or the visual scene to investigate how visual and body orientation cues are combined for the control of unseen arm movements. Subjects were asked to point toward a visual target using an upward movement during slow body and/or visual scene tilts. When the scene was tilted, final pointing errors varied as a function of the direction of the scene tilt (forward or backward). Actual forward body tilt resulted in systematic target undershoots, suggesting that the brain may have overcompensated for the biomechanical movement facilitation arising from body tilt. Combined body and visual scene tilts also affected final pointing errors according to the orientation of the visual scene. The data were further analysed using either a body-centered or a gravity-centered reference frame to encode visual scene orientation with simple additive models (i.e., 'combined' tilts equal to the sum of 'single' tilts). We found that the body-centered model could account only for some of the data regarding kinematic parameters and final errors. In contrast, the gravity-centered modeling in which the body and visual scene orientations were referred to vertical could explain all of these data. Therefore, our findings suggest that the brain uses gravity, thanks to its invariant properties, as a reference for the combination of visual and non-visual cues.

  17. Illusion of arm movement evoked by tendon vibration in patients with spinal cord injury.

    Science.gov (United States)

    Fusco, Gabriele; Tidoni, Emmanuele; Barone, Nicola; Pilati, Claudio; Aglioti, Salvatore Maria

    2016-09-21

    Studies in healthy people show that stimulation of muscle spindles through frequency-specific tendon vibration (TV) induces the illusory perception of movement. Following spinal cord injury (SCI), motor and sensory connections between the brain and parts of the body below-the-lesion level are partially or totally impaired. The present investigation is a descriptive study aimed to investigate whether people living with SCI may experience movement illusions comparable to a control group. Healthy and people with SCI were asked to report on three illusion-related features (Vividness, Duration, Illusory Extension) after receiving 70 Hz TV on the biceps brachii tendon of both arms. Two different forces of stimulation were applied: 2.4 N and 4.2 N. Both patients and controls were susceptible to the kinesthetic illusion. However patients presented lower sensitivity to TV than healthy subjects. Participants rated stronger illusions of movement after 4.2 N than 2.4 N stimulation in all the three illusion-related features. Further, patients reported atypical illusory experiences of movement (e.g. as if the arm wanted to extend, or a sensation of pushing against something) that may reflect different reorganization processes following spinal cord injury. The study provides a preliminary evidence of the possible use of the proprioceptive stimulation in the upper limbs of people living with SCI. Results are discussed in the light of recent advancements of brain-computer applications based on motor imagery for the control of neuroprosthetic and robotic devices in patients with severe sensorimotor deficits.

  18. Combined influence of visual scene and body tilt on arm pointing movements: gravity matters!

    Directory of Open Access Journals (Sweden)

    Cécile Scotto Di Cesare

    Full Text Available Performing accurate actions such as goal-directed arm movements requires taking into account visual and body orientation cues to localize the target in space and produce appropriate reaching motor commands. We experimentally tilted the body and/or the visual scene to investigate how visual and body orientation cues are combined for the control of unseen arm movements. Subjects were asked to point toward a visual target using an upward movement during slow body and/or visual scene tilts. When the scene was tilted, final pointing errors varied as a function of the direction of the scene tilt (forward or backward. Actual forward body tilt resulted in systematic target undershoots, suggesting that the brain may have overcompensated for the biomechanical movement facilitation arising from body tilt. Combined body and visual scene tilts also affected final pointing errors according to the orientation of the visual scene. The data were further analysed using either a body-centered or a gravity-centered reference frame to encode visual scene orientation with simple additive models (i.e., 'combined' tilts equal to the sum of 'single' tilts. We found that the body-centered model could account only for some of the data regarding kinematic parameters and final errors. In contrast, the gravity-centered modeling in which the body and visual scene orientations were referred to vertical could explain all of these data. Therefore, our findings suggest that the brain uses gravity, thanks to its invariant properties, as a reference for the combination of visual and non-visual cues.

  19. Ictal SPECT in patients with rapid eye movement sleep behaviour disorder.

    Science.gov (United States)

    Mayer, Geert; Bitterlich, Marion; Kuwert, Torsten; Ritt, Philipp; Stefan, Hermann

    2015-05-01

    Rapid eye movement sleep behaviour disorder is a rapid eye movement parasomnia clinically characterized by acting out dreams due to disinhibition of muscle tone in rapid eye movement sleep. Up to 80-90% of the patients with rapid eye movement sleep behaviour disorder develop neurodegenerative disorders within 10-15 years after symptom onset. The disorder is reported in 45-60% of all narcoleptic patients. Whether rapid eye movement sleep behaviour disorder is also a predictor for neurodegeneration in narcolepsy is not known. Although the pathophysiology causing the disinhibition of muscle tone in rapid eye movement sleep behaviour disorder has been studied extensively in animals, little is known about the mechanisms in humans. Most of the human data are from imaging or post-mortem studies. Recent studies show altered functional connectivity between substantia nigra and striatum in patients with rapid eye movement sleep behaviour disorder. We were interested to study which regions are activated in rapid eye movement sleep behaviour disorder during actual episodes by performing ictal single photon emission tomography. We studied one patient with idiopathic rapid eye movement sleep behaviour disorder, one with Parkinson's disease and rapid eye movement sleep behaviour disorder, and two patients with narcolepsy and rapid eye movement sleep behaviour disorder. All patients underwent extended video polysomnography. The tracer was injected after at least 10 s of consecutive rapid eye movement sleep and 10 s of disinhibited muscle tone accompanied by movements registered by an experienced sleep technician. Ictal single photon emission tomography displayed the same activation in the bilateral premotor areas, the interhemispheric cleft, the periaqueductal area, the dorsal and ventral pons and the anterior lobe of the cerebellum in all patients. Our study shows that in patients with Parkinson's disease and rapid eye movement sleep behaviour disorder-in contrast to wakefulness

  20. [Electromyography Analysis of Rapid Eye Movement Sleep Behavior Disorder].

    Science.gov (United States)

    Nakano, Natsuko; Kinoshita, Fumiya; Takada, Hiroki; Nakayama, Meiho

    2018-01-01

    Polysomnography (PSG), which records physiological phenomena including brain waves, breathing status, and muscle tonus, is useful for the diagnosis of sleep disorders as a gold standard. However, measurement and analysis are complex for several specific sleep disorders, such as rapid eye movement (REM) sleep behavior disorder (RBD). Usually, brain waves during REM sleep indicate an awakening pattern under relaxed conditions of skeletal and antigravity muscles. However, these muscles are activated during REM sleep when patients suffer from RBD. These activated muscle movements during REM, so-called REM without atonia (RWA) recorded by PSG, may be related to a neurodegenerative disease such as Parkinson's disease. Thus, careful analysis of RWA is significant not only physically, but also clinically. Commonly, manual viewing measurement analysis of RWA is time-consuming. Therefore, quantitative studies on RWA are rarely reported. A software program, developed from Microsoft Office Excel ® , was used to semiautomatically analyze the RWA ratio extracted from PSG to compare with manual viewing measurement analysis. In addition, a quantitative muscle tonus study was carried out to evaluate the effect of medication on RBD patients. Using this new software program, we were able to analyze RWA on the same cases in approximately 15 min as compared with 60 min in the manual viewing measurement analysis. This software program can not only quantify RWA easily but also identify RWA waves for either phasic or tonic bursts. We consider that this software program will support physicians and scientists in their future research on RBD. We are planning to offer this software program for free to physicians and scientists.

  1. Dopamine transporter imaging in rapid eye movement sleep behavior disorder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Kyeong; Yoon, In Young; Kim, Jong Min; Jeong, Seok Hoon; Kim, Ji Sun; Lee, Byung Chul; Lee, Won Woo; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    The pathogenesis of rapid eye movement (REM) sleep behavior disorder (RBD) is still unknown. However, involvement of dopaminergic system in RBD has been hypothesized because of frequent association with degenerative movement disorders such as Parkinson's disease. The purpose of this study was to examine the extent and pattern of loss of dopamine transporter in RBD using FP-CIT SPECT. Fourteen patient with idiopathic RBD (mean age:665 yrs, M:F=10:3) participated in this study. Polysonmography confirmed loss of REM atonia and determined RBD severities by amount of tonic/phasic muscle activity during REM sleep in all cases. To compare with RBD, 14 early idiopathic Parkinson's disease rated as Hoehn and Yahr stage 1 (IPD) and 12 healthy controls were also selected. All participants performed single-photon emission computed tomography (SPECT) imaging 3 hours after injection of [123I]FP-CIT. Regions of interest were drawn on bilateral caudate and putamen, whole striatum and occipital cortex. Specific binding for dopamine transporters (DAT) were calculated using region to occipital uptake ratio based on the transient equilibrium method. Overall mean of DAT density in the striatum was lower in RBD group than controls, and higher than IPD group, However, DAT density in most individual RBD was still within normal range, and total striatal DAT density was not correlated with severity of RBD. Meanwhile, the caudate to putamen uptake ratio (C/P ratio) in RBD group was insignificantly higher than those in healthy controls. Nevertheless, C/P ratio within RBD group was reversely correlated with the RBD severity. Our study suggested that nigrostriatal dopaminergic degeneration could be a part of the pathogenesis of RBD, but not essential for the development of RBD. Further longitudinal evaluation of presynaptic dopaminergic system in idiopathic RBD may guarantee the more understanding for RBD and associated neurodegenerative disease.

  2. Effects of bandwidth feedback on the automatization of an arm movement sequence.

    Science.gov (United States)

    Agethen, Manfred; Krause, Daniel

    2016-02-01

    We examined the effects of a bandwidth feedback manipulation on motor learning. Effects on movement accuracy, as well as on movement consistency, have been addressed in earlier studies. We have additionally investigated the effects on motor automatization. Because providing error feedback is believed to induce attentional control processes, we suppose that a bandwidth method should facilitate motor automatization. Participants (N=48) were assigned to four groups: one control group and three intervention groups. Participants of the intervention groups practiced an arm movement sequence with 760 trials. The BW0-Group practiced with 100% frequency of feedback. For the BW10-Group, feedback was provided when the errors were larger than 10°. The YokedBW10-Group participants were matched to the feedback schedule of research twins from the BW10-Group. All groups performed pre-tests and retention tests with a secondary task paradigm to test for automaticity. The BW10-Group indicated a higher degree of automatization compared with the BW0-Group, which did not exhibit a change in automaticity. The comparison of the YokedBW10-Group, which also exhibited automatization, and the BW10-Group leads to the proposal that reduction of quantitative feedback frequency and additional positive feedback are responsible for the bandwidth effect. Differences in movement accuracy and consistency were not evident. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Restricted Arm Swing Affects Gait Stability and Increased Walking Speed Alters Trunk Movements in Children with Cerebral Palsy

    Science.gov (United States)

    Delabastita, Tijs; Desloovere, Kaat; Meyns, Pieter

    2016-01-01

    Observational research suggests that in children with cerebral palsy, the altered arm swing is linked to instability during walking. Therefore, the current study investigates whether children with cerebral palsy use their arms more than typically developing children, to enhance gait stability. Evidence also suggests an influence of walking speed on gait stability. Moreover, previous research highlighted a link between walking speed and arm swing. Hence, the experiment aimed to explore differences between typically developing children and children with cerebral palsy taking into account the combined influence of restricting arm swing and increasing walking speed on gait stability. Spatiotemporal gait characteristics, trunk movement parameters and margins of stability were obtained using three dimensional gait analysis to assess gait stability of 26 children with cerebral palsy and 24 typically developing children. Four walking conditions were evaluated: (i) free arm swing and preferred walking speed; (ii) restricted arm swing and preferred walking speed; (iii) free arm swing and high walking speed; and (iv) restricted arm swing and high walking speed. Double support time and trunk acceleration variability increased more when arm swing was restricted in children with bilateral cerebral palsy compared to typically developing children and children with unilateral cerebral palsy. Trunk sway velocity increased more when walking speed was increased in children with unilateral cerebral palsy compared to children with bilateral cerebral palsy and typically developing children and in children with bilateral cerebral palsy compared to typically developing children. Trunk sway velocity increased more when both arm swing was restricted and walking speed was increased in children with bilateral cerebral palsy compared to typically developing children. It is proposed that facilitating arm swing during gait rehabilitation can improve gait stability and decrease trunk movements in

  4. A novel robotic system for quantifying arm kinematics and kinetics: description and evaluation in therapist-assisted passive arm movements post-stroke.

    Science.gov (United States)

    Culmer, P R; Jackson, A E; Makower, S G; Cozens, J A; Levesley, M C; Mon-Williams, M; Bhakta, B

    2011-04-30

    We developed a system for quantitatively measuring arm movement. Our approach provides a method to simultaneously capture upper limb kinetic and kinematic data during assisted passive arm movements. Data are analysed with respect to Cartesian and upper limb coordinate systems to obtain upper limb joint angles and torques. We undertook an evaluation of the system in participants with stroke to show the feasibility of this approach. During rehabilitation after stroke, one aspect of treatment includes the physiotherapist applying assistive forces to move the impaired arm of the patient who remains passive. There is a dearth of published data on the relationship between upper limb kinematics and the underlying forces (kinetics) in this mode of physiotherapy treatment. Such quantitative data are crucial in facilitating research into therapy practice, for example by measuring variation in practice and determining dosage. An experienced therapist prescribed passive movements tailored to the needs of 16 participants with stroke (41-81 years) with a range of anthropometric sizes and motor impairments. Our novel measurement tool recorded kinematic and kinetic data at 100 Hz for 6-11 movements per participant. The kinetic data show that the majority of movements fall within upper limits of 36.7 N in shoulder elevation, 22.4N in shoulder protraction, 4.6 Nm in shoulder abduction, 12.8 Nm in shoulder flexion, 2.4 Nm in shoulder rotation and 5.5 Nm in elbow flexion. These data show the potential of this system to better understand arm movement, in particular to objectively evaluate physical therapy treatments and support development of robotic devices to facilitate upper limb rehabilitation. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Do periodic arm movements during sleep exist in healthy subjects? A polysomnographic study.

    Science.gov (United States)

    Gabelia, David; Mitterling, Thomas; Högl, Birgit; Wenning, Gregor K; Frauscher, Birgit

    2014-09-01

    Despite several polysomnographic studies on periodic leg movements (PLM) in healthy sleep, data on the prevalence and characteristics of periodic arm movements (PAM) in normal subjects are lacking. We aimed to investigate PAM and their association with PLM during wakefulness and sleep in healthy subjects. Ninety-one participants underwent video-polysomnography according to American Academy of Sleep Medicine 2007 criteria. In addition to standard electromyographic registration, data for both flexor digitorum superficialis muscles were recorded. Sixty-two subjects (68.1%) had a PAM index during wakefulness >5/h (median PAM index during wakefulness, 8.8/h; range, 0-77). Seven subjects (7.7%) had a PAM index >5/h during sleep (median PAM index during sleep, 0.7/h; range, 0-47.4). In 14% of cases, PAM during wakefulness were coincident with PLM during wakefulness. During sleep, this coincidence was not evident. The correlation between PAM and PLM was weak to moderate (during wakefulness: Spearman's ρ = 0.576, P sleep: Spearman's ρ = 0.222, P = 0.036). In healthy subjects, PAM occur predominantly during wakefulness with no apparent true periodicity. In contrast to classical PLM, some PAM may not present a true periodic phenomenon, but rather random voluntary movements meeting the wide range of periodicity criteria for PLM. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Effective Propulsion in Swimming: Grasping the Hydrodynamics of Hand and Arm Movements.

    Science.gov (United States)

    van Houwelingen, Josje; Schreven, Sander; Smeets, Jeroen B J; Clercx, Herman J H; Beek, Peter J

    2017-02-01

    In this paper, a literature review is presented regarding the hydrodynamic effects of different hand and arm movements during swimming with the aim to identify lacunae in current methods and knowledge, and to distil practical guidelines for coaches and swimmers seeking to increase swimming speed. Experimental and numerical studies are discussed, examining the effects of hand orientation, thumb position, finger spread, sculling movements, and hand accelerations during swimming, as well as unsteady properties of vortices due to changes in hand orientation. Collectively, the findings indicate that swimming speed may be increased by avoiding excessive sculling movements and by spreading the fingers slightly. In addition, it appears that accelerating the hands rather than moving them at constant speed may be beneficial, and that (in front crawl swimming) the thumb should be abducted during entry, catch, and upsweep, and adducted during the pull phase. Further experimental and numerical research is required to confirm these suggestions and to elucidate their hydrodynamic underpinnings and identify optimal propulsion techniques. To this end, it is necessary that the dynamical motion and resulting unsteady effects are accounted for, and that flow visualization techniques, force measurements, and simulations are combined in studying those effects.

  7. Bobath Concept versus constraint-induced movement therapy to improve arm functional recovery in stroke patients: a randomized controlled trial.

    Science.gov (United States)

    Huseyinsinoglu, Burcu Ersoz; Ozdincler, Arzu Razak; Krespi, Yakup

    2012-08-01

    To compare the effects of the Bobath Concept and constraint-induced movement therapy on arm functional recovery among stroke patients with a high level of function on the affected side. A single-blinded, randomized controlled trial. Outpatient physiotherapy department of a stroke unit. A total of 24 patients were randomized to constraint-induced movement therapy or Bobath Concept group. The Bobath Concept group was treated for 1 hour whereas the constraint-induced movement therapy group received training for 3 hours per day during 10 consecutive weekdays. Main measures were the Motor Activity Log-28, the Wolf Motor Function Test, the Motor Evaluation Scale for Arm in Stroke Patients and the Functional Independence Measure. The two groups were found to be homogeneous based on demographic variables and baseline measurements. Significant improvements were seen after treatment only in the 'Amount of use' and 'Quality of movement' subscales of the Motor Activity Log-28 in the constraint-induced movement therapy group over the the Bobath Concept group (P = 0.003; P = 0.01 respectively). There were no significant differences in Wolf Motor Function Test 'Functional ability' (P = 0.137) and 'Performance time' (P = 0.922), Motor Evaluation Scale for Arm in Stroke Patients (P = 0.947) and Functional Independence Measure scores (P = 0.259) between the two intervention groups. Constraint-induced movement therapy and the Bobath Concept have similar efficiencies in improving functional ability, speed and quality of movement in the paretic arm among stroke patients with a high level of function. Constraint-induced movement therapy seems to be slightly more efficient than the Bobath Concept in improving the amount and quality of affected arm use.

  8. A rapid method of detecting motor blocks in patients with Parkinson's disease during volitional hand movements

    Directory of Open Access Journals (Sweden)

    Popović Mirjana B.

    2002-01-01

    -5%; 56% had MBT% 5-10%; 22% had MBT% 10-15%; 5.5% had MBT% 15-20°% and 2% had MBT% 20-25%. No block lasted more than 25% from the whole movement duration. Table 2 is the summary of mean variability for kinematic indicators of motor block (N, mbt%, t% and for the movement duration T during a 7 day-testing of patients #3. The analysis of calculated data for eight tested PD patients revealed a significant difference (p < 0.01 between healthy controls and three PD patients; data on five PD patients were not significantly different (ns. This method clustered 3 PD patients in the group that experience motor blocks, while the rest were in the group without their significant occurrence. DISCUSSION This algorithm is an additional instrument in classical evaluation of PD patients during their clinical evaluation and treatment. It provides to clinician a rapid feedback on the changes of voluntary hand movements in everyday progress of illness. Furthermore, this method could be of assistance for developing strategies to overcome motor blocks in arm movements at their beginning, as well as for the feedback of the success of drug therapy.

  9. Feasibility and Effectiveness of a Novel Exoskeleton for an Infant With Arm Movement Impairments.

    Science.gov (United States)

    Babik, Iryna; Kokkoni, Elena; Cunha, Andrea B; Galloway, James Cole; Rahman, Tariq; Lobo, Michele A

    2016-01-01

    To determine whether a novel exoskeletal device (Pediatric-Wilmington Robotic Exoskeleton [P-WREX]) is feasible and effective for intervention to improve reaching and object interaction for an infant with arm movement impairments. An 8-month old infant with arthrogryposis was followed up every 2 weeks during a 1-month baseline, 3-month intervention, and 1-month postintervention. At each visit, reaching and looking behaviors were assessed. Within sessions, the infant spent more time contacting objects across a larger space, contacting objects with both hands, and looking at objects when wearing the P-WREX. Throughout intervention, the infant increased time contacting objects both with and without the device and increased bilateral active shoulder flexion. (1) It may be feasible for families to use exoskeletons for daily intervention, (2) exoskeletons facilitate immediate improvements in function for infants with impaired upper extremity mobility, and (3) interventions using exoskeletons can improve independent upper extremity function across time.

  10. Robotically facilitated virtual rehabilitation of arm transport integrated with finger movement in persons with hemiparesis

    Science.gov (United States)

    2011-01-01

    Background Recovery of upper extremity function is particularly recalcitrant to successful rehabilitation. Robotic-assisted arm training devices integrated with virtual targets or complex virtual reality gaming simulations are being developed to deal with this problem. Neural control mechanisms indicate that reaching and hand-object manipulation are interdependent, suggesting that training on tasks requiring coordinated effort of both the upper arm and hand may be a more effective method for improving recovery of real world function. However, most robotic therapies have focused on training the proximal, rather than distal effectors of the upper extremity. This paper describes the effects of robotically-assisted, integrated upper extremity training. Methods Twelve subjects post-stroke were trained for eight days on four upper extremity gaming simulations using adaptive robots during 2-3 hour sessions. Results The subjects demonstrated improved proximal stability, smoothness and efficiency of the movement path. This was in concert with improvement in the distal kinematic measures of finger individuation and improved speed. Importantly, these changes were accompanied by a robust 16-second decrease in overall time in the Wolf Motor Function Test and a 24-second decrease in the Jebsen Test of Hand Function. Conclusions Complex gaming simulations interfaced with adaptive robots requiring integrated control of shoulder, elbow, forearm, wrist and finger movements appear to have a substantial effect on improving hemiparetic hand function. We believe that the magnitude of the changes and the stability of the patient's function prior to training, along with maintenance of several aspects of the gains demonstrated at retention make a compelling argument for this approach to training. PMID:21575185

  11. Robotically facilitated virtual rehabilitation of arm transport integrated with finger movement in persons with hemiparesis

    Directory of Open Access Journals (Sweden)

    Davidow Amy

    2011-05-01

    Full Text Available Abstract Background Recovery of upper extremity function is particularly recalcitrant to successful rehabilitation. Robotic-assisted arm training devices integrated with virtual targets or complex virtual reality gaming simulations are being developed to deal with this problem. Neural control mechanisms indicate that reaching and hand-object manipulation are interdependent, suggesting that training on tasks requiring coordinated effort of both the upper arm and hand may be a more effective method for improving recovery of real world function. However, most robotic therapies have focused on training the proximal, rather than distal effectors of the upper extremity. This paper describes the effects of robotically-assisted, integrated upper extremity training. Methods Twelve subjects post-stroke were trained for eight days on four upper extremity gaming simulations using adaptive robots during 2-3 hour sessions. Results The subjects demonstrated improved proximal stability, smoothness and efficiency of the movement path. This was in concert with improvement in the distal kinematic measures of finger individuation and improved speed. Importantly, these changes were accompanied by a robust 16-second decrease in overall time in the Wolf Motor Function Test and a 24-second decrease in the Jebsen Test of Hand Function. Conclusions Complex gaming simulations interfaced with adaptive robots requiring integrated control of shoulder, elbow, forearm, wrist and finger movements appear to have a substantial effect on improving hemiparetic hand function. We believe that the magnitude of the changes and the stability of the patient's function prior to training, along with maintenance of several aspects of the gains demonstrated at retention make a compelling argument for this approach to training.

  12. Gating of Tactile Information through Gamma Band during Passive Arm Movement in Awake Primates

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    Weiguo eSong

    2015-10-01

    Full Text Available To make precise and prompt action in a dynamic environment, the sensorimotor system needs to integrate all related information. The inflow of somatosensory information to the cerebral cortex is regulated and mostly suppressed by movement, which is commonly referred to as sensory gating or gating. Sensory gating plays an important role in preventing redundant information from reaching the cortex, which should be considered when designing somatosensory neuroprosthetics. Gating can occur at several levels within the sensorimotor pathway, while the underlying mechanism is not yet fully understood. The average sensory evoked potential is commonly used to assess sensory information processing, however the assumption of a stereotyped response to each stimulus is under debated. Event related spectral perturbation (ERSP, which is the power spectrum after time-frequency decomposition on single trial evoked potentials (total power, could overcome this limitation of averaging and provide additional information for understanding the underlying mechanism. To this aim, neural activities in primary somatosensory cortex (S1, primary motor cortex (M1 and ventral posterolateral (VPL nucleus of thalamus were recorded simultaneously in two areas (S1 and M1 or S1 and VPL during passive arm movement and rest in awake monkeys. Our results showed that neural activity at different recording areas demonstrated specific and unique response frequency characteristics. Tactile input induced early high frequency responses followed by low frequency oscillations within sensorimotor circuits, and passive movement suppressed these oscillations either in a phase-locked or non-phase-locked manner. Sensory gating by movement was non-phase-locked in M1, and complex in sensory areas. VPL showed gating of non-phase-locked at gamma band and mix of phase-locked and non-phase-locked at low frequency, while S1 showed gating of phase-locked and non-phase-locked at gamma band and an early

  13. Quantitative Assessment of the Arm/Hand Movements in Parkinson’s Disease Using a Wireless Armband Device

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    Sofija Spasojević

    2017-08-01

    Full Text Available We present an approach for quantitative assessment of the arm/hand movements in patients with Parkinson’s disease (PD, from sensor data acquired with a wearable, wireless armband device (Myo sensor. We propose new Movement Performance Indicators that can be adopted by practitioners for the quantitative evaluation of motor performance and support their clinical evaluations. In addition, specific Movement Performance Indicators can indicate the presence of the bradykinesia symptom. The study includes seventeen PD patients and sixteen age-matched controls. A set of representative arm/hand movements is defined under the supervision of movement disorder specialist. In order to assist the evaluations, and for progress monitoring purposes, as well as for assessing the amount of bradykinesia in PD, a total set of 84 Movement Performance Indicators are computed from the sensor readings. Subsequently, we investigate whether wireless armband device, with the use of the proposed Movement Performance Indicators can be utilized: (1 for objective and precise quantitative evaluation of the arm/hand movements of Parkinson’s patients, (2 for assessment of the bradykinesia motor symptom, and (3 as an adequate low-cost alternative for the sensor glove. We conducted extensive analysis of proposed Movement Performance Indicators and results are indicating following clinically relevant characteristics: (i adequate reliability as measured by ICC; (ii high accuracy in discrimination between the patients and controls, and between the disease stages (support to disease diagnosis and progress monitoring, respectively; (iii substantial difference in comparison between the left-hand and the right-hand movements across controls and patients, as well as between disease stage groups; (iv statistically significant correlation with clinical scales (tapping test and UPDRS-III Motor Score; and (v quantitative evaluation of bradykinesia symptom. Results suggest that the proposed

  14. Robotic measurement of arm movements after stroke establishes biomarkers of motor recovery.

    Science.gov (United States)

    Krebs, Hermano I; Krams, Michael; Agrafiotis, Dimitris K; DiBernardo, Allitia; Chavez, Juan C; Littman, Gary S; Yang, Eric; Byttebier, Geert; Dipietro, Laura; Rykman, Avrielle; McArthur, Kate; Hajjar, Karim; Lees, Kennedy R; Volpe, Bruce T

    2014-01-01

    Because robotic devices record the kinematics and kinetics of human movements with high resolution, we hypothesized that robotic measures collected longitudinally in patients after stroke would bear a significant relationship to standard clinical outcome measures and, therefore, might provide superior biomarkers. In patients with moderate-to-severe acute ischemic stroke, we used clinical scales and robotic devices to measure arm movement 7, 14, 21, 30, and 90 days after the event at 2 clinical sites. The robots are interactive devices that measure speed, position, and force so that calculated kinematic and kinetic parameters could be compared with clinical assessments. Among 208 patients, robotic measures predicted well the clinical measures (cross-validated R(2) of modified Rankin scale=0.60; National Institutes of Health Stroke Scale=0.63; Fugl-Meyer=0.73; Motor Power=0.75). When suitably scaled and combined by an artificial neural network, the robotic measures demonstrated greater sensitivity in measuring the recovery of patients from day 7 to day 90 (increased standardized effect=1.47). These results demonstrate that robotic measures of motor performance will more than adequately capture outcome, and the altered effect size will reduce the required sample size. Reducing sample size will likely improve study efficiency.

  15. Minimum acceleration criterion with constraints implies bang-bang control as an underlying principle for optimal trajectories of arm reaching movements.

    Science.gov (United States)

    Ben-Itzhak, Shay; Karniel, Amir

    2008-03-01

    Rapid arm-reaching movements serve as an excellent test bed for any theory about trajectory formation. How are these movements planned? A minimum acceleration criterion has been examined in the past, and the solution obtained, based on the Euler-Poisson equation, failed to predict that the hand would begin and end the movement at rest (i.e., with zero acceleration). Therefore, this criterion was rejected in favor of the minimum jerk, which was proved to be successful in describing many features of human movements. This letter follows an alternative approach and solves the minimum acceleration problem with constraints using Pontryagin's minimum principle. We use the minimum principle to obtain minimum acceleration trajectories and use the jerk as a control signal. In order to find a solution that does not include nonphysiological impulse functions, constraints on the maximum and minimum jerk values are assumed. The analytical solution provides a three-phase piecewise constant jerk signal (bang-bang control) where the magnitude of the jerk and the two switching times depend on the magnitude of the maximum and minimum available jerk values. This result fits the observed trajectories of reaching movements and takes into account both the extrinsic coordinates and the muscle limitations in a single framework. The minimum acceleration with constraints principle is discussed as a unifying approach for many observations about the neural control of movements.

  16. The role of anticipatory postural adjustments in interlimb coordination of coupled arm movements in the parasagittal plane: III. difference in the energy cost of postural actions during cyclic flexion-extension arm movements, ISO- and ANTI-directionally coupled.

    Science.gov (United States)

    Esposti, Roberto; Limonta, Eloisa; Esposito, Fabio; Baldissera, Fausto G

    2013-11-01

    When oscillating the upper limbs together in the parasagittal plane, movements coordination is lower (i.e., variability of the interlimb relative phase is higher) in antidirectional (ANTI) than in isodirectional (ISO) coupling. In contrast, we previously observed that for arm movements in the horizontal plane, the coordination was worse in ISO than ANTI and the energetic cost of postural activities was higher in ISO. Having hypothesised that the higher postural cost was one factor responsible for the coordination deficit in horizontal ISO, we measured the oxygen uptake ([Formula: see text]) in parasagittal movements, expecting that in this case too, the postural cost is higher in the less-coordinated mode (ANTI). Breath-by-breath metabolic ([Formula: see text], [Formula: see text]) and cardiorespiratory (HR, [Formula: see text]) parameters were measured in seven participants, who performed cyclic flexions-extensions in the parasagittal plane with either one arm or both arms, in ISO or ANTI coupling and at 1.4, 2.2 and 2.6 Hz. In each condition, the intermittent exercise (12 s movement, 12 s rest) lasted 264 s. A force platform recorded the mechanical actions to the ground. The exercise metabolic cost ([Formula: see text]) was found to be significantly higher in parasagittal ANTI than ISO. The movement amplitude being equal in the two modes, the ANTI-ISO difference should be ascribed to postural activities. This would confirm that the less-coordinated coupling mode requires the higher postural effort in parasagittal movements too. When rising the movement frequency, [Formula: see text] increased and linearly correlated with the coordination loss. Comparison of parasagittal with horizontal movements showed that [Formula: see text] was lower in parasagittal ANTI than in horizontal ISO (the less-coordinated modes), while it was not different between parasagittal ISO and horizontal ANTI (the more-coordinated modes).

  17. Robot-assisted reaching exercise promotes arm movement recovery in chronic hemiparetic stroke: a randomized controlled pilot study

    Directory of Open Access Journals (Sweden)

    Rymer W Zev

    2006-06-01

    Full Text Available Abstract Background and purpose Providing active assistance to complete desired arm movements is a common technique in upper extremity rehabilitation after stroke. Such active assistance may improve recovery by affecting somatosensory input, motor planning, spasticity or soft tissue properties, but it is labor intensive and has not been validated in controlled trials. The purpose of this study was to investigate the effects of robotically administered active-assistive exercise and compare those with free reaching voluntary exercise in improving arm movement ability after chronic stroke. Methods Nineteen individuals at least one year post-stroke were randomized into one of two groups. One group performed 24 sessions of active-assistive reaching exercise with a simple robotic device, while a second group performed a task-matched amount of unassisted reaching. The main outcome measures were range and speed of supported arm movement, range, straightness and smoothness of unsupported reaching, and the Rancho Los Amigos Functional Test of Upper Extremity Function. Results and discussion There were significant improvements with training for range of motion and velocity of supported reaching, straightness of unsupported reaching, and functional movement ability. These improvements were not significantly different between the two training groups. The group that performed unassisted reaching exercise improved the smoothness of their reaching movements more than the robot-assisted group. Conclusion Improvements with both forms of exercise confirmed that repeated, task-related voluntary activation of the damaged motor system is a key stimulus to motor recovery following chronic stroke. Robotically assisting in reaching successfully improved arm movement ability, although it did not provide any detectable, additional value beyond the movement practice that occurred concurrently with it. The inability to detect any additional value of robot-assisted reaching

  18. Postural adjustments during spontaneous and goal-directed arm movements in the first half year of life

    NARCIS (Netherlands)

    van der Fits, IBM; Klip, AWJ; van Eykern, LA; Hadders-Algra, M

    1999-01-01

    We studied the development of postural control during goal-directed reaching and spontaneous arm movements in early infancy. Two groups of infants participated. The first group consisted of 10 healthy infants, who were assessed four times at the ages of 3, 4, 5 and 6 months. Each assessment

  19. A Developmental Study of Static Postural Control and Superimposed Arm Movements in Normal and Slowly Developing Children.

    Science.gov (United States)

    Fisher, Janet M.

    Selected electromyographic parameters underlying static postural control in 4, 6, and 8 year old normally and slowly developing children during performance of selected arm movements were studied. Developmental delays in balance control were assessed by the Cashin Test of Motor Development (1974) and/or the Williams Gross Motor Coordination Test…

  20. Design and development of the first exoskeletal garment to enhance arm mobility for children with movement impairments.

    Science.gov (United States)

    Hall, Martha L; Lobo, Michele A

    2017-05-25

    Children with a variety of diagnoses have impairments that limit their arm function. Despite the fact that arm function is important for early learning and activities of daily living, there are few tools to assist movement for these children, and existing devices have challenges related to cost, accessibility, comfort, and aesthetics. In this article, we describe the design process and development of the first garment-based exoskeleton to assist arm movement in young children with movement impairments: the Playskin Lift TM . We outline our design process, which contrasts with the traditional medical model in that it is interdisciplinary, user-centered, and addresses the broad needs of users, rather than device function alone. Then we report the results of field-testing with the initial prototype with respect to our design metrics on a toddler with significant bilateral arm movement impairments. Finally, we summarize our ongoing development aimed at increasing comfort, aesthetics, and accessibility of the garment. The interdisciplinary, user-centered approach to assistive technology design presented here can result in innovative and impactful design solutions that translate to the real world.

  1. The role of anticipatory postural adjustments in interlimb coordination of coupled arm movements in the parasagittal plane: II. Postural activities and coupling coordination during cyclic flexion-extension arm movements, ISO- and ANTI-directionally coupled.

    Science.gov (United States)

    Baldissera, Fausto G; Esposti, Roberto

    2013-08-01

    When coupling cyclic adduction-abduction movements of the arms in the transverse (horizontal) plane, isodirectional (ISO) coupling is less stable than antidirectional (ANTI) coupling. We proposed that such deficiency stems from the disturbing action that anticipatory postural adjustments exert on ISO coupling. To ascertain if postural adjustments differentiate ISO versus ANTI coupling coordination in other types of cyclic arm movements, we examined flexion-extension oscillations in the parasagittal plane. Oscillations of the right arm alone elicited cyclic Postural Adjustments (PAs) in the left Anterior Deltoid and Posterior Deltoid, which replicated the excitation-inhibition pattern of the prime movers right Anterior Deltoid, right Posterior Deltoid. Cyclic PAs also developed symmetrically in Erector Spinae (RES and LES) and in phase opposition in Ischiocruralis (RIC and LIC), so as to discharge to the ground both an anteroposterior force, Fy, and a moment about the vertical axis, Tz. Oscillations of both arms in ISO coupling induced symmetric PAs in both ES and IC muscles, thus generating a large Fy but no Tz. In ANTI coupling, PAs in RES and LES remained symmetric but smaller in size, while PAs in RIC and LIC were large and opposite in phase, resulting in a large Tz and small Fy. Altogether, PAs would thus favour ISO and hamper ANTI parasagittal movements because (1) in the motor pathways to the prime movers of either arm, a convergence would occur between the voluntary commands and the commands for PAs linked to the movement of the other arm, the two commands having the same sign (excitatory or inhibitory) during ISO and an opposite sign during ANTI; (2) the postural effort of trunk and leg muscles would be higher for generating Tz in ANTI than Fy in ISO. These predictions fit with the finding that coupling stability was lower in ANTI than in ISO, i.e., opposite to horizontal movements. In conclusion, in both parasagittal and horizontal arm movements, the less

  2. Rapid Eye Movement and Non-Rapid Eye Movement Sleep Contributions in Memory Consolidation and Resistance to Retroactive Interference for Verbal Material

    Science.gov (United States)

    Deliens, Gaétane; Leproult, Rachel; Neu, Daniel; Peigneux, Philippe

    2013-01-01

    Study Objectives: To test the hypothesis that rapid eye movement (REM) sleep contributes to the consolidation of new memories, whereas non-rapid eye movement (NREM) sleep contributes to the prevention of retroactive interference. Design: Randomized, crossover study. Setting: Two sessions of either a morning nap or wakefulness. Participants: Twenty-five healthy young adults. Interventions: Declarative learning of word pairs followed by a nap or a wake interval, then learning of interfering word pairs and delayed recall of list A. Measurements and Results: After a restricted night (24:00-06:00), participants learned a list of word pairs (list A). They were then required to either take a nap or stay awake during 45 min, after which they learned a second list of word pairs (list B) and then had to recall list A. Fifty percent of word pairs in list B shared the first word with list A, resulting in interference. Ten subjects exhibited REM sleep whereas 13 subjects exhibited NREM stage 3 (N3) sleep. An interference effect was observed in the nap but not in the wake condition. In post-learning naps, N3 sleep was associated with a reduced interference effect, which was not the case for REM sleep. Moreover, participants exhibiting N3 sleep in the post-learning nap condition also showed a reduced interference effect in the wake condition, suggesting a higher protection ability against interference. Conclusion: Our results partly support the hypothesis that non-rapid eye movement sleep contributes in protecting novel memories against interference. However, rapid eye movement sleep-related consolidation is not evidenced. Citation: Deliens G; Leproult R; Neu D; Peigneux P. Rapid eye movement and non-rapid eye movement sleep contributions in memory consolidation and resistance to retroactive interference for verbal material. SLEEP 2013;36(12):1875-1883. PMID:24293762

  3. Rapid eye movement sleep disturbances in Huntington disease

    DEFF Research Database (Denmark)

    Arnulf, I.; Nielsen, J.; Lohmann, E.

    2008-01-01

    Background: Sleep disorders including insomnia, movements during sleep, and daytime sleepiness are common but poorly studied in Huntington disease (HD). Objective: To evaluate the HD sleep-wake phenotype (including abnormal motor activity during sleep) in patients with various HD stages and the l......Background: Sleep disorders including insomnia, movements during sleep, and daytime sleepiness are common but poorly studied in Huntington disease (HD). Objective: To evaluate the HD sleep-wake phenotype (including abnormal motor activity during sleep) in patients with various HD stages...

  4. Influence of head orientation on visually and memory-guided arm movements.

    Science.gov (United States)

    Guerraz, Michel; Caudron, Sébastien; Thomassin, Noémylle; Blouin, Jean

    2011-03-01

    In the absence of visual supervision, tilting the head sideways gives rise to deviations in spatially defined arm movements. The purpose of this study was to determine whether these deviations are restricted to situations with impoverished visual information. Two experiments were conducted in which participants were positioned supine and reproduced with their unseen index finger a 2 dimensional figure either under visual supervision or from memory (eyes closed). In the former condition, the figure remained visible (using a mirror). In the latter condition, the figure was first observed and then reproduced from memory. Participants' head was either aligned with the trunk or tilted 30° towards the left or right shoulder. In experiment 1, participants observed first the figure with the head straight and then reproduced it with the head either aligned or tilted sideways. In Experiment 2, participants observed the figure with the head in the position in which the figure was later reproduced. Results of Experiment 1 and 2 showed deviations of the motor reproduction in the direction opposite to the head in both the memory and visually-guided conditions. However, the deviations decreased significantly under visual supervision when the head was tilted left. In Experiment 1, the perceptual visual bias induced by head tilt was evaluated. Participants were required to align the figure parallel to their median trunk axis. Results revealed that the figure was perceived as parallel with the trunk when it was actually tilted in the direction of the head. Perceptual and motor responses did not correlate. Therefore, as long as visual feedback of the arm is prevented, an internal bias, likely originating from head/trunk representation, alters hand-motor production irrespectively of whether visual feedback of the figure is available or not. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Rapid eye movement sleep behavior disorder in patients with probable Alzheimer's disease.

    Science.gov (United States)

    Wang, Pan; Wing, Yun Kwok; Xing, Jianli; Liu, Yong; Zhou, Bo; Zhang, Zengqiang; Yao, Hongxiang; Guo, Yan'e; Shang, Yanchang; Zhang, Xi

    2016-10-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is commonly associated with neurodegenerative disorders characterized by α-synuclein deposition, including Parkinson's disease, multiple system atrophy, and Lewy body dementia. However, this tendency in tauopathy-mediated diseases is rare and only sporadically reported. We systematically illustrate the occurrence of RBD and sleep features among a cohort of patients with Alzheimer's disease (AD), a non-synucleinopathy. We recruited 105 clinically probable AD patients. Fifteen clinically probable AD patients with suspected RBD underwent a video-polysomnography (vPSG) examination. Five patients with probable AD exhibited RBD. One of the patients performed repeated touching of the head and the face with his hands and flailed his arms. Three patients exhibited hand twisting, exploring, prominent limb kicking, and jerking. The fifth patient exhibited all of the characteristics of RBD (he recalled a dream about fighting animals), and his wife was awakened by his screaming. Of these five patients, one patient took the acetylcholinesterase inhibitor drug donepezil. The patients with AD + RBD demonstrated increases in both tonic and phasic electromyography activity during REM sleep, but sleep architecture did not differ between the AD + RBD and AD-alone groups. RBD can occur in patients with AD. The occurrence of RBD does not change the sleep architecture of AD patients.

  6. Sensorimotor modulation by botulinum toxin A in post-stroke arm spasticity: Passive hand movement.

    Science.gov (United States)

    Veverka, Tomáš; Hluštík, Petr; Hok, Pavel; Otruba, Pavel; Zapletalová, Jana; Tüdös, Zbyněk; Krobot, Alois; Kaňovský, Petr

    2016-03-15

    In post-stroke spasticity, functional imaging may uncover modulation in the central sensorimotor networks associated with botulinum toxin type A (BoNT) therapy. Investigations were performed to localize brain activation changes in stroke patients treated with BoNT for upper limb spasticity using functional magnetic resonance imaging (fMRI). Seven ischemic stroke patients (4 females; mean age 58.86) with severe hand paralysis and notable spasticity were studied. Spasticity was scored according to the modified Ashworth scale (MAS). fMRI examination was performed 3 times: before (W0) and 4 (W4) and 11weeks (W11) after BoNT. The whole-brain fMRI data were acquired during paced repetitive passive movements of the plegic hand (flexion/extension at the wrist) alternating with rest. Voxel-by-voxel statistical analysis using the General Linear Model (GLM) implemented in FSL (v6.00)/FEAT yielded group session-wise statistical maps and paired between-session contrasts, thresholded at the corrected cluster-wise significance level of psensorimotor cortex (M1, S1, and SMA) dominated. At W4, additional clusters transiently emerged bilaterally in the cerebellum, in the contralesional sensorimotor cortex, and in the contralesional occipital cortex. Paired contrasts demonstrated significant differences W4>W0 (bilateral cerebellum and contralesional occipital cortex) and W4>W11 (ipsilesional cerebellum and SMA). The remaining paired contrast (W0>W11) showed activation decreases mainly in the ipsilesional sensorimotor cortex (M1, S1, and SMA). The present study confirms the feasibility of using passive hand movements to map the cerebral sensorimotor networks in patients with post-stroke arm spasticity and demonstrates that BoNT-induced spasticity relief is associated with changes in task-induced central sensorimotor activation, likely mediated by an altered afferent drive from the spasticity-affected muscles. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Decoding of the spike timing of primary afferents during voluntary arm movements in monkeys

    Directory of Open Access Journals (Sweden)

    Tatsuya eUmeda

    2014-05-01

    Full Text Available Understanding the mechanisms of encoding forelimb kinematics in the activity of peripheral afferents is essential for determining the optimal parameters of afferent stimulation to transmit proprioceptive signals in neuroprosthetics. To investigate whether the spike timing of dorsal root ganglion (DRG neurons could be estimated from the forelimb kinematics of behaving monkeys, we implanted two multi-electrode arrays chronically in the DRGs at the level of the cervical segments in two monkeys. Neuronal activity during voluntary reach-to-grasp movements were recorded simultaneously with the trajectories of hand/arm movements, which were tracked in three-dimensional space using a motion capture system. Sixteen and 13 neurons, including muscle spindles, skin receptors, and tendon organ afferents, were recorded in the two monkeys, respectively. We were able to reconstruct forelimb joint kinematics from the temporal firing pattern of a subset of DRG neurons using sparse linear regression (SLiR analysis, suggesting that DRG neuronal ensembles encoded information about joint kinematics. Furthermore, we estimated the spike timing of the DRG neuronal ensembles from joint kinematics using an integrate-and-fire model (IF incorporating the SLiR algorithm. The temporal change of firing frequency of a subpopulation of neurons was reconstructed precisely from forelimb kinematics using the SLiR. The spike timing of the DRG neurons was calculated using an IF model, in which a spike occurs if the cumulative sum of the firing frequency value exceeded a constant threshold. The estimated firing pattern of the DRG neuronal ensembles encoded forelimb joint angles and velocities as precisely as the originally recorded neuronal activity. These results suggest that the simple model can be used to generate an accurate estimate of the spike timing of DRG neuronal ensembles from forelimb joint kinematics, and is useful for designing a proprioceptive decoder in a brain machine

  8. Rapid intermittent movement of axonal neurofilaments observed by fluorescence photobleaching

    National Research Council Canada - National Science Library

    Wang, L; Brown, A

    2001-01-01

    Observations on naturally occurring gaps in the axonal neurofilament array of cultured neurons have demonstrated that neurofilament polymers move along axons in a rapid, intermittent, and highly asynchronous manner...

  9. Analyzing power spectral of electroencephalogram (EEG) signal to identify motoric arm movement using EMOTIV EPOC+

    Science.gov (United States)

    Bustomi, A.; Wijaya, S. K.; Prawito

    2017-07-01

    Rehabilitation of motoric dysfunction from the body becomes the main objective of developing Brain Computer Interface (BCI) technique, especially in the field of medical rehabilitation technology. BCI technology based on electrical activity of the brain, allow patient to be able to restore motoric disfunction of the body and help them to overcome the shortcomings mobility. In this study, EEG signal phenomenon was obtained from EMOTIV EPOC+, the signals were generated from the imagery of lifting arm, and look for any correlation between the imagery of motoric muscle movement against the recorded signals. The signals processing were done in the time-frequency domain, using Wavelet relative power (WRP) as feature extraction, and Support vector machine (SVM) as the classifier. In this study, it was obtained the result of maximum accuracy of 81.3 % using 8 channel (AF3, F7, F3, FC5, FC6, F4, F8, and AF4), 6 channel remaining on EMOTIV EPOC + does not contribute to the improvement of the accuracy of the classification system

  10. Brain-machine interface to control a prosthetic arm with monkey ECoGs during periodic movements.

    Science.gov (United States)

    Morishita, Soichiro; Sato, Keita; Watanabe, Hidenori; Nishimura, Yukio; Isa, Tadashi; Kato, Ryu; Nakamura, Tatsuhiro; Yokoi, Hiroshi

    2014-01-01

    Brain-machine interfaces (BMIs) are promising technologies for rehabilitation of upper limb functions in patients with severe paralysis. We previously developed a BMI prosthetic arm for a monkey implanted with electrocorticography (ECoG) electrodes, and trained it in a reaching task. The stability of the BMI prevented incorrect movements due to misclassification of ECoG patterns. As a trade-off for the stability, however, the latency (the time gap between the monkey's actual motion and the prosthetic arm movement) was about 200 ms. Therefore, in this study, we aimed to improve the response time of the BMI prosthetic arm. We focused on the generation of a trigger event by decoding muscle activity in order to predict integrated electromyograms (iEMGs) from the ECoGs. We verified the achievability of our method by conducting a performance test of the proposed method with actual achieved iEMGs instead of predicted iEMGs. Our results confirmed that the proposed method with predicted iEMGs eliminated the time delay. In addition, we found that motor intention is better reflected by muscle activity estimated from brain activity rather than actual muscle activity. Therefore, we propose that using predicted iEMGs to guide prosthetic arm movement results in minimal delay and excellent performance.

  11. The nasal and gut microbiome in Parkinson's disease and idiopathic rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Heintz-Buschart, Anna; Pandey, Urvashi; Wicke, Tamara; Sixel-Döring, Friederike; Janzen, Annette; Sittig-Wiegand, Elisabeth; Trenkwalder, Claudia; Oertel, Wolfgang H; Mollenhauer, Brit; Wilmes, Paul

    2017-08-26

    Increasing evidence connects the gut microbiota and the onset and/or phenotype of Parkinson's disease (PD). Differences in the abundances of specific bacterial taxa have been reported in PD patients. It is, however, unknown whether these differences can be observed in individuals at high risk, for example, with idiopathic rapid eye movement sleep behavior disorder, a prodromal condition of α-synuclein aggregation disorders including PD. To compare microbiota in carefully preserved nasal wash and stool samples of subjects with idiopathic rapid eye movement sleep behavior disorder, manifest PD, and healthy individuals. Microbiota of flash-frozen stool and nasal wash samples from 76 PD patients, 21 idiopathic rapid eye movement sleep behavior disorder patients, and 78 healthy controls were assessed by 16S and 18S ribosomal RNA amplicon sequencing. Seventy variables, related to demographics, clinical parameters including nonmotor symptoms, and sample processing, were analyzed in relation to microbiome variability and controlled differential analyses were performed. Differentially abundant gut microbes, such as Akkermansia, were observed in PD, but no strong differences in nasal microbiota. Eighty percent of the differential gut microbes in PD versus healthy controls showed similar trends in idiopathic rapid eye movement sleep behavior disorder, for example, Anaerotruncus and several Bacteroides spp., and correlated with nonmotor symptoms. Metagenomic sequencing of select samples enabled the reconstruction of genomes of so far uncharacterized differentially abundant organisms. Our study reveals differential abundances of gut microbial taxa in PD and its prodrome idiopathic rapid eye movement sleep behavior disorder in comparison to the healthy controls, and highlights the potential of metagenomics to identify and characterize microbial taxa, which are enriched or depleted in PD and/or idiopathic rapid eye movement sleep behavior disorder. © 2017 The Authors. Movement

  12. Robust adaptive control modeling of human arm movements subject to altered gravity and mechanical loads

    Science.gov (United States)

    Tryfonidis, Michail

    It has been observed that during orbital spaceflight the absence of gravitation related sensory inputs causes incongruence between the expected and the actual sensory feedback resulting from voluntary movements. This incongruence results in a reinterpretation or neglect of gravity-induced sensory input signals. Over time, new internal models develop, gradually compensating for the loss of spatial reference. The study of adaptation of goal-directed movements is the main focus of this thesis. The hypothesis is that during the adaptive learning process the neural connections behave in ways that can be described by an adaptive control method. The investigation presented in this thesis includes two different sets of experiments. A series of dart throwing experiments took place onboard the space station Mir. Experiments also took place at the Biomechanics lab at MIT, where the subjects performed a series of continuous trajectory tracking movements while a planar robotic manipulandum exerted external torques on the subjects' moving arms. The experimental hypothesis for both experiments is that during the first few trials the subjects will perform poorly trying to follow a prescribed trajectory, or trying to hit a target. A theoretical framework is developed that is a modification of the sliding control method used in robotics. The new control framework is an attempt to explain the adaptive behavior of the subjects. Numerical simulations of the proposed framework are compared with experimental results and predictions from competitive models. The proposed control methodology extends the results of the sliding mode theory to human motor control. The resulting adaptive control model of the motor system is robust to external dynamics, even those of negative gain, uses only position and velocity feedback, and achieves bounded steady-state error without explicit knowledge of the system's nonlinearities. In addition, the experimental and modeling results demonstrate that

  13. The nature of arm movement in children with cerebral palsy when using computer-generated exercise games.

    Science.gov (United States)

    Weightman, Andrew; Preston, Nick; Levesley, Martin; Bhakta, Bipin; Holt, Raymond; Mon-Williams, Mark

    2014-05-01

    To compare upper limb kinematics of children with spastic cerebral palsy (CP) using a passive rehabilitation joystick with those of adults and able-bodied children, to better understand the design requirements of computer-based rehabilitation devices. A blocked comparative study involving seven children with spastic CP, nine able-bodied adults and nine able-bodied children, using a joystick system to play a computer game whilst the kinematics of their upper limb were recorded. The translational kinematics of the joystick's end point and the participant's shoulder movement (protraction/retraction) and elbow rotational kinematics (flexion/extension) were analysed for each group. Children with spastic CP matched their able-bodied peers in the time taken to complete the computer task, but this was due to a failure to adhere to the task instructions of travelling along a prescribed straight line when moving between targets. The spastic CP group took longer to initiate the first movement, which showed jerkier trajectories and demonstrated qualitatively different movement patterns when using the joystick, with shoulder movements that were significantly of greater magnitude than the able-bodied participants. Children with spastic CP generate large shoulder and hence trunk movements when using a joystick to undertake computer-generated arm exercises. This finding has implications for the development and use of assistive technologies to encourage exercise and the instructions given to users of such systems. A kinematic analysis of upper limb function of children with CP when using joystick devices is presented. Children with CP may use upper body movements to compensate for limitations in voluntary shoulder and elbow movements when undertaking computer games designed to encourage the practice of arm movement. The design of rehabilitative computer exercise systems should consider movement of the torso/shoulder as it may have implications for the quality of therapy in the

  14. A reliability study on brain activation during active and passive arm movements supported by an MRI-compatible robot.

    Science.gov (United States)

    Estévez, Natalia; Yu, Ningbo; Brügger, Mike; Villiger, Michael; Hepp-Reymond, Marie-Claude; Riener, Robert; Kollias, Spyros

    2014-11-01

    In neurorehabilitation, longitudinal assessment of arm movement related brain function in patients with motor disability is challenging due to variability in task performance. MRI-compatible robots monitor and control task performance, yielding more reliable evaluation of brain function over time. The main goals of the present study were first to define the brain network activated while performing active and passive elbow movements with an MRI-compatible arm robot (MaRIA) in healthy subjects, and second to test the reproducibility of this activation over time. For the fMRI analysis two models were compared. In model 1 movement onset and duration were included, whereas in model 2 force and range of motion were added to the analysis. Reliability of brain activation was tested with several statistical approaches applied on individual and group activation maps and on summary statistics. The activated network included mainly the primary motor cortex, primary and secondary somatosensory cortex, superior and inferior parietal cortex, medial and lateral premotor regions, and subcortical structures. Reliability analyses revealed robust activation for active movements with both fMRI models and all the statistical methods used. Imposed passive movements also elicited mainly robust brain activation for individual and group activation maps, and reliability was improved by including additional force and range of motion using model 2. These findings demonstrate that the use of robotic devices, such as MaRIA, can be useful to reliably assess arm movement related brain activation in longitudinal studies and may contribute in studies evaluating therapies and brain plasticity following injury in the nervous system.

  15. Chunk concatenation evolves with practice and sleep-related enhancement consolidation in a complex arm movement sequence

    Directory of Open Access Journals (Sweden)

    Blischke Klaus

    2016-06-01

    Full Text Available This paper addresses the notion of chunk concatenation being associated with sleep-related enhancement consolidation of motor sequence memory, thereby essentially contributing to improvements in sequence execution speed. To this end, element movement times of a multi-joint arm movement sequence incorporated in a recent study by Malangré et al. (2014 were reanalyzed. As sequence elements differed with respect to movement distance, element movement times had to be purged from differences solely due to varying trajectory lengths. This was done by dividing each element movement time per subject and trial block by the respective “reference movement time” collected from subjects who had extensively practiced each sequence element in isolation. Any differences in these “relative element movement times” were supposed to reflect element-specific “production costs” imposed solely by the sequence context. Across all subjects non-idiosyncratic, lasting sequence segmentation was shown, and four possible concatenation points (i.e. transition points between successive chunks within the original arm movement sequence were identified. Based on theoretical suppositions derived from previous work with the discrete sequence production task and the dual processor model (Abrahamse et al., 2013, significantly larger improvements in transition speed occurring at these four concatenation points as compared to the five fastest transition positions within the sequence (associated with mere element execution were assumed to indicate increased chunk concatenation. As a result, chunk concatenation was shown to proceed during acquisition with physical practice, and, most importantly, to significantly progress some more during retention following a night of sleep, but not during a waking interval.

  16. Rapid eye movement sleep behavior disorder in Parkinson's disease: magnetic resonance imaging study.

    Science.gov (United States)

    Ford, Andrew H; Duncan, Gordon W; Firbank, Michael J; Yarnall, Alison J; Khoo, Tien K; Burn, David J; O'Brien, John T

    2013-06-01

    Rapid eye movement sleep behavior disorder has poor prognostic implications for Parkinson's disease. The authors recruited 124 patients with early Parkinson's disease to compare clinical and neuroimaging findings based on the presence of this sleep disorder. The presence of rapid eye movement sleep behavior disorder was assessed with the Mayo Sleep Questionnaire. Magnetic resonance imaging sequences were obtained for voxel-based morphometry and diffusion tensor imaging. Patients with sleep disorder had more advanced disease, but groups had similar clinical characteristics and cognitive performance. Those with sleep disorder had areas of reduced cortical grey matter volume and white matter changes compared with those who did not have sleep disorder. However, differences were slight and were not significant when the analyses were adjusted for multiple comparisons. Rapid eye movement sleep behavior disorder was associated with subtle changes in white matter integrity and grey matter volume in patients with early Parkinson's disease. Copyright © 2013 Movement Disorder Society.

  17. Origins and violations of the 2/3 power law in rhythmic three-dimensional arm movements.

    Science.gov (United States)

    Schaal, S; Sternad, D

    2001-01-01

    The 2/3 power law, the nonlinear relationship between tangential velocity and radius of curvature of the end-effector trajectory, is thought to be a fundamental constraint of the central nervous system in the formation of rhythmic endpoint trajectories. However, studies on the 2/3 power law have been confined largely to planar drawing patterns of relatively small size. With the hypothesis that this strategy overlooks nonlinear effects that are constitutive in movement generation, the present experiments tested the validity of the power law in elliptical patterns that were not confined to a planar surface and which were performed by the unconstrained 7-degrees of freedom (DOF) arm, with significant variations in pattern size and workspace orientation. Data were recorded from five human subjects where the seven joint angles and the endpoint trajectories were analyzed. Additionally, an anthropomorphic 7-DOF robot arm served as a "control subject" whose endpoint trajectories were generated on the basis of the human joint angle data, modeled as simple harmonic oscillations. Analyses of the endpoint trajectories demonstrate that the power law is systematically violated with increasing pattern size, in both exponent and the goodness of fit. The origins of these violations can be explained analytically based on smooth, rhythmic trajectory formation and the kinematic structure of the human arm. We conclude that, in unconstrained rhythmic movements, the power law seems to be a by-product of a movement system that favors smooth trajectories, and that it is unlikely to serve as a primary movement-generating principle. Our data rather suggest that subjects employed smooth oscillatory pattern generators in joint space to realize the required movement patterns.

  18. Computerized method for arm movement assessment in Parkinson's disease and cerebellar syndrome patients

    Directory of Open Access Journals (Sweden)

    Đorđević Olivera

    2005-01-01

    Full Text Available In clinical setting, the symptoms of the impaired motor behavior in patients with different neurological diseases are identified by classical tests incorporated in clinical neurological examination. New computerized methods for objective motor assessment have been recently suggested in the literature. We developed computerized method for assessment and evaluation of arm movement in patients with Parkinson's disease (PD in early phase and in patients with cerebellar syndrome. Method is based on automatic acquisition of hand coordinates during drawing of line and circle, and offline analysis of kinematic parameters (time duration, path length, mean and maximal velocity, velocity profile, and precision. Clinical application is in recognition and follow-up of the impaired kinematic parameters, specific for these two groups of patients. AIM We propose computerized method that consists of two motor tasks: Task 1- drawing a line defined with end points; and Task 2 - drawing a circle defined by referential model. The first task was rather simple with defined direction, and the second included continuous change of the direction that required permanent adjustment. The aim was to detect which kinematic parameters were particularly different in PD and in patients with cerebellar syndrome in relation to healthy controls, and then to apply this method as an additional instrument in clinical evaluation. METHODS Hand trajectories were assessed during simple self-paced 1 point-to-point movement-Task 1; and 2 circle-Task 2, by cordless magnetic mouse in a hand on digitizing board (Drawing board III, 305x457 mm, GTCO Cal Comp Inc. The subjects were seated in a relaxed manner on the chair adjusted to the table height, and instructed not to correct drawn line during performance of a task. The first session was for practicing the tests only, and in the next session, the subjects repeated 5 times each task. All sessions were videotaped with CCD camera. Testing

  19. Robot-Assisted Training of Arm and Hand Movement Shows Functional Improvements for Incomplete Cervical Spinal Cord Injury.

    Science.gov (United States)

    Francisco, Gerard E; Yozbatiran, Nuray; Berliner, Jeffrey; OʼMalley, Marcia K; Pehlivan, Ali Utku; Kadivar, Zahra; Fitle, Kyle; Boake, Corwin

    2017-10-01

    The aim of the study was to demonstrate the feasibility, tolerability, and effectiveness of robotic-assisted arm training in incomplete chronic tetraplegia. Pretest/posttest/follow-up was conducted. Ten individuals with chronic cervical spinal cord injury were enrolled. Participants performed single degree-of-freedom exercise of upper limbs at an intensity of 3-hr per session for 3 times a week for 4 wks with MAHI Exo-II. Arm and hand function tests (Jebsen-Taylor Hand Function Test, Action Research Arm Test), strength of upper limb (upper limb motor score, grip, and pinch strength), and independence in daily living activities (Spinal Cord Independence Measure II) were performed at baseline, end of training, and 6 mos later. After 12 sessions of training, improvements in arm and hand functions were observed. Jebsen-Taylor Hand Function Test (0.14[0.04]-0.21[0.07] items/sec, P = 0.04), Action Research Arm Test (30.7[3.8]-34.3[4], P = 0.02), American Spinal Injury Association upper limb motor score (31.5[2.3]-34[2.3], P = 0.04) grip (9.7[3.8]-12[4.3] lb, P = 0.02), and pinch strength (4.5[1.1]-5.7[1.2] lb, P = 0.01) resulted in significant increases. Some gains were maintained at 6 mos. No change in Spinal Cord Independence Measure II scores and no adverse events were observed. Results from this pilot study suggest that repetitive training of arm movements with MAHI Exo-II exoskeleton is safe and has potential to be an adjunct treatment modality in rehabilitation of persons with spinal cord injury with mild to moderate impaired arm functions.

  20. Recent data on rapid eye movement sleep behavior disorder in patients with Parkinson disease: analysis of behaviors, movements, and periodic limb movements.

    Science.gov (United States)

    Cochen De Cock, Valérie

    2013-08-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a fascinating parasomnia in which patients are able to enact their dreams because of a lack of muscle atonia during REM sleep. RBD represents a unique window into the dream world. Frequently associated with Parkinson's disease (PD), RBD raises various issues about dream modifications in this pathology and about aggressiveness during RBD episodes in placid patients during wakefulness. Studies on these behaviors have underlined their non-stereotyped, action-filled and violent characteristics but also their isomorphism with dream content. Complex, learnt behaviors may reflect the cortical involvement in this parasomnia but the more frequent elementary movements and the associated periodic limb movements during sleep also implicate the brainstem. Surprisingly, patients with PD have an improvement of their movements during their RBD as if they were disease-free. Also not yet understood, this improvement of movement during REM sleep raises issues about the pathways involved in RBD and about the possibility of using this pathway to improve movement in PD during the day. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Quality of life in patients with an idiopathic rapid eye movement sleep behaviour disorder in Korea.

    Science.gov (United States)

    Kim, Keun Tae; Motamedi, Gholam K; Cho, Yong Won

    2017-08-01

    There have been few quality of life studies in patients with idiopathic rapid eye movement sleep behaviour disorder. We compared the quality of life in idiopathic rapid eye movement sleep behaviour disorder patients to healthy controls, patients with hypertension, type 2 diabetes mellitus without complication and idiopathic restless legs syndrome. Sixty patients with idiopathic rapid eye movement sleep behaviour disorder (24 female; mean age: 61.43 ± 8.99) were enrolled retrospectively. The diagnosis was established based on sleep history, overnight polysomnography, neurological examination and Mini-Mental State Examination to exclude secondary rapid eye movement sleep behavior disorder. All subjects completed questionnaires, including the Short Form 36-item Health Survey for quality of life. The total quality of life score in idiopathic rapid eye movement sleep behaviour disorder (70.63 ± 20.83) was lower than in the healthy control group (83.38 ± 7.96) but higher than in the hypertension (60.55 ± 24.82), diabetes mellitus (62.42 ± 19.37) and restless legs syndrome (61.77 ± 19.25) groups. The total score of idiopathic rapid eye movement sleep behaviour disorder patients had a negative correlation with the Pittsburg Sleep Quality Index (r = -0.498, P Health Survey score and the Insomnia Severity Index (β = -1.100, P = 0.001) and Beck Depression Inventory-2 (β = -1.038, P sleep behaviour disorder had a significant negative impact on quality of life, although this effect was less than that of other chronic disorders. This negative effect might be related to a depressive mood associated with the disease. © 2016 European Sleep Research Society.

  2. A modified constraint-induced movement therapy (CIT) program improves paretic arm use and function in children with cerebral palsy.

    Science.gov (United States)

    Smania, N; Aglioti, S M; Cosentino, A; Camin, M; Gandolfi, M; Tinazzi, M; Fiaschi, A; Faccioli, S

    2009-12-01

    Constraint-induced movement therapy (CIT) is a rehabilitation intervention put forward by Taub and colleagues for sensorimotor disorders in children with hemiparesis, comprising consisting of the restraint of the unaffected arm and concurrent intensive training of the affected arm for six hours/day for two weeks. The aim of this study was to evaluate the effectiveness of a modified CIT program (mCIT) characterized by restraining the unaffected hand with a cotton mitten during daily activities and a reduced intensity training program for two h/week for five weeks. Ten children (age: 1-9 years) with hemiparetic cerebral palsy were enrolled in a randomized, cross-over study in which the effects of a mCIT and a conventional physiotherapy program were compared. The amount of use and the functional performance of the affected arm were evaluated by means of two specifically devised tests (Use and Function Test). A further test evaluated functional performance during bimanual tasks. These measures showed a good inter-rater and inter-session reliability. All tests were administered before, at the end and four weeks after treatment. Significant differences between the two therapeutic approaches were evidenced in both affected arm use (P=0.008) and function (P=0.018). These improvements maintained at the follow-up (Use Test P=0.07; paretic arm function P=0.012). Bimanual function performance showed a trend towards improvement in both post-treatment and follow-up testing. The conventional physiotherapy group did not show any improvement in any outcome measure. The mCIT program proposed in the present study showed to be a promising rehabilitative procedure in children with congenital arm paresis after cerebral palsy.

  3. Using Functional Electrical Stimulation Mediated by Iterative Learning Control and Robotics to Improve Arm Movement for People With Multiple Sclerosis.

    Science.gov (United States)

    Sampson, Patrica; Freeman, Chris; Coote, Susan; Demain, Sara; Feys, Peter; Meadmore, Katie; Hughes, Ann-Marie

    2016-02-01

    Few interventions address multiple sclerosis (MS) arm dysfunction but robotics and functional electrical stimulation (FES) appear promising. This paper investigates the feasibility of combining FES with passive robotic support during virtual reality (VR) training tasks to improve upper limb function in people with multiple sclerosis (pwMS). The system assists patients in following a specified trajectory path, employing an advanced model-based paradigm termed iterative learning control (ILC) to adjust the FES to improve accuracy and maximise voluntary effort. Reaching tasks were repeated six times with ILC learning the optimum control action from previous attempts. A convenience sample of five pwMS was recruited from local MS societies, and the intervention comprised 18 one-hour training sessions over 10 weeks. The accuracy of tracking performance without FES and the amount of FES delivered during training were analyzed using regression analysis. Clinical functioning of the arm was documented before and after treatment with standard tests. Statistically significant results following training included: improved accuracy of tracking performance both when assisted and unassisted by FES; reduction in maximum amount of FES needed to assist tracking; and less impairment in the proximal arm that was trained. The system was well tolerated by all participants with no increase in muscle fatigue reported. This study confirms the feasibility of FES combined with passive robot assistance as a potentially effective intervention to improve arm movement and control in pwMS and provides the basis for a follow-up study.

  4. A passive movement method for parameter estimation of a musculo-skeletal arm model incorporating a modified hill muscle model.

    Science.gov (United States)

    Yu, Tung Fai; Wilson, Adrian J

    2014-05-01

    In this paper we present an experimental method of parameterising the passive mechanical characteristics of the bicep and tricep muscles in vivo, by fitting the dynamics of a two muscle arm model incorporating anatomically meaningful and structurally identifiable modified Hill muscle models to measured elbow movements. Measurements of the passive flexion and extension of the elbow joint were obtained using 3D motion capture, from which the elbow angle trajectories were determined and used to obtain the spring constants and damping coefficients in the model through parameter estimation. Four healthy subjects were used in the experiments. Anatomical lengths and moment of inertia values of the subjects were determined by direct measurement and calculation. There was good reproducibility in the measured arm movement between trials, and similar joint angle trajectory characteristics were seen between subjects. Each subject had their own set of fitted parameter values determined and the results showed good agreement between measured and simulated data. The average fitted muscle parallel spring constant across all subjects was 143 N/m and the average fitted muscle parallel damping constant was 1.73 Ns/m. The passive movement method was proven to be successful, and can be applied to other joints in the human body, where muscles with similar actions are grouped together. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  5. The role of rapid eye movement sleep for amygdala-related memory processing

    NARCIS (Netherlands)

    Genzel, L.K.E.; Spoormaker, V.I.; Konrad, B.N.; Dresler, M.

    2015-01-01

    Over the years, rapid eye movement (REM) sleep has been associated with general memory consolidation, specific consolidation of perceptual, procedural, emotional and fear memories, brain maturation and preparation of waking consciousness. More recently, some of these associations (e.g., general and

  6. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...

  7. Rapid eye movement sleep behaviour disorder in patients with narcolepsy is associated with hypocretin-1 deficiency

    DEFF Research Database (Denmark)

    Knudsen, Stine; Gammeltoft, Steen; Jennum, Poul J

    2010-01-01

    variables were analysed in relation to cataplexy and hypocretin deficiency with uni- and multivariate logistic/linear regression models, controlling for possible rapid eye movement sleep behaviour disorder biasing factors (age, gender, disease duration, previous anti-cataplexy medication). Only hypocretin...

  8. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical and neu...

  9. A system-level mathematical model of Basal Ganglia motor-circuit for kinematic planning of arm movements.

    Science.gov (United States)

    Salimi-Badr, Armin; Ebadzadeh, Mohammad Mehdi; Darlot, Christian

    2018-01-01

    In this paper, a novel system-level mathematical model of the Basal Ganglia (BG) for kinematic planning, is proposed. An arm composed of several segments presents a geometric redundancy. Thus, selecting one trajectory among an infinite number of possible ones requires overcoming redundancy, according to some kinds of optimization. Solving this optimization is assumed to be the function of BG in planning. In the proposed model, first, a mathematical solution of kinematic planning is proposed for movements of a redundant arm in a plane, based on minimizing energy consumption. Next, the function of each part in the model is interpreted as a possible role of a nucleus of BG. Since the kinematic variables are considered as vectors, the proposed model is presented based on the vector calculus. This vector model predicts different neuronal populations in BG which is in accordance with some recent experimental studies. According to the proposed model, the function of the direct pathway is to calculate the necessary rotation of each joint, and the function of the indirect pathway is to control each joint rotation considering the movement of the other joints. In the proposed model, the local feedback loop between Subthalamic Nucleus and Globus Pallidus externus is interpreted as a local memory to store the previous amounts of movements of the other joints, which are utilized by the indirect pathway. In this model, activities of dopaminergic neurons would encode, at short-term, the error between the desired and actual positions of the end-effector. The short-term modulating effect of dopamine on Striatum is also modeled as cross product. The model is simulated to generate the commands of a redundant manipulator. The performance of the model is studied for different reaching movements between 8 points in a plane. Finally, some symptoms of Parkinson's disease such as bradykinesia and akinesia are simulated by modifying the model parameters, inspired by the dopamine depletion

  10. Disrupted rapid eye movement sleep predicts poor declarative memory performance in post-traumatic stress disorder.

    Science.gov (United States)

    Lipinska, Malgorzata; Timol, Ridwana; Kaminer, Debra; Thomas, Kevin G F

    2014-06-01

    Successful memory consolidation during sleep depends on healthy slow-wave and rapid eye movement sleep, and on successful transition across sleep stages. In post-traumatic stress disorder, sleep is disrupted and memory is impaired, but relations between these two variables in the psychiatric condition remain unexplored. We examined whether disrupted sleep, and consequent disrupted memory consolidation, is a mechanism underlying declarative memory deficits in post-traumatic stress disorder. We recruited three matched groups of participants: post-traumatic stress disorder (n = 16); trauma-exposed non-post-traumatic stress disorder (n = 15); and healthy control (n = 14). They completed memory tasks before and after 8 h of sleep. We measured sleep variables using sleep-adapted electroencephalography. Post-traumatic stress disorder-diagnosed participants experienced significantly less sleep efficiency and rapid eye movement sleep percentage, and experienced more awakenings and wake percentage in the second half of the night than did participants in the other two groups. After sleep, post-traumatic stress disorder-diagnosed participants retained significantly less information on a declarative memory task than controls. Rapid eye movement percentage, wake percentage and sleep efficiency correlated with retention of information over the night. Furthermore, lower rapid eye movement percentage predicted poorer retention in post-traumatic stress disorder-diagnosed individuals. Our results suggest that declarative memory consolidation is disrupted during sleep in post-traumatic stress disorder. These data are consistent with theories suggesting that sleep benefits memory consolidation via predictable neurobiological mechanisms, and that rapid eye movement disruption is more than a symptom of post-traumatic stress disorder. © 2014 European Sleep Research Society.

  11. Inter-Joint Coordination Deficits Revealed in the Decomposition of Endpoint Jerk During Goal-Directed Arm Movement After Stroke.

    Science.gov (United States)

    Laczko, Jozsef; Scheidt, Robert A; Simo, Lucia S; Piovesan, Davide

    2017-07-01

    It is well documented that neurological deficits after stroke can disrupt motor control processes that affect the smoothness of reaching movements. The smoothness of hand trajectories during multi-joint reaching depends on shoulder and elbow joint angular velocities and their successive derivatives as well as on the instantaneous arm configuration and its rate of change. Right-handed survivors of unilateral hemiparetic stroke and neurologically-intact control participants held the handle of a two-joint robot and made horizontal planar reaching movements. We decomposed endpoint jerk into components related to shoulder and elbow joint angular velocity, acceleration, and jerk. We observed an abnormal decomposition pattern in the most severely impaired stroke survivors consistent with deficits of inter-joint coordination. We then used numerical simulations of reaching movements to test whether the specific pattern of inter-joint coordination deficits observed experimentally could be explained by either a general increase in motor noise related to weakness or by an impaired ability to compensate for multi-joint interaction torque. Simulation results suggest that observed deficits in movement smoothness after stroke more likely reflect an impaired ability to compensate for multi-joint interaction torques rather than the mere presence of elevated motor noise.

  12. LINKING MOTOR-RELATED BRAIN POTENTIALS AND VELOCITY PROFILES IN MULTI-JOINT ARM REACHING MOVEMENTS

    Directory of Open Access Journals (Sweden)

    Julià L Amengual

    2014-04-01

    Full Text Available The study of the movement related brain potentials (MRPBs needs accurate technical approaches to disentangle the specific patterns of bran activity during the preparation and execution of movements. During the last forty years, synchronizing the electromiographic activation (EMG of the muscle with the electrophysiological recordings (EEG has been commonly ussed for these purposes. However, new clinical approaches in the study of motor diseases and rehabilitation suggest the demand of new paradigms that might go further into the study of the brain activity associated with the kinematics of movement. As a response to this call, we have used a 3-D hand tracking system with the aim to record continuously the position of an ultrasonic sender located on the hand during the performance of multi-joint self-pace movements. We synchronized the time-series of position of velocity of the sender with the EEG recordings, obtaining specific patterns of brain activity as a function of the fluctuations of the kinematics during the natural movement performance. Additionally, the distribution of the brain activity during the preparation and execution phases of movement was similar that reported previously using the EMG, suggesting the validity of our technique. We claim that this paradigm could be usable in patients because of its simplicity and the potential knowledge that can be extracted from clinical protocols.

  13. Rapid eye movements during sleep in mice: high trait-like stability qualifies rapid eye movement density for characterization of phenotypic variation in sleep patterns of rodents.

    Science.gov (United States)

    Fulda, Stephany; Romanowski, Christoph P N; Becker, Andreas; Wetter, Thomas C; Kimura, Mayumi; Fenzel, Thomas

    2011-11-02

    In humans, rapid eye movements (REM) density during REM sleep plays a prominent role in psychiatric diseases. Especially in depression, an increased REM density is a vulnerability marker for depression. In clinical practice and research measurement of REM density is highly standardized. In basic animal research, almost no tools are available to obtain and systematically evaluate eye movement data, although, this would create increased comparability between human and animal sleep studies. We obtained standardized electroencephalographic (EEG), electromyographic (EMG) and electrooculographic (EOG) signals from freely behaving mice. EOG electrodes were bilaterally and chronically implanted with placement of the electrodes directly between the musculus rectus superior and musculus rectus lateralis. After recovery, EEG, EMG and EOG signals were obtained for four days. Subsequent to the implantation process, we developed and validated an Eye Movement scoring in Mice Algorithm (EMMA) to detect REM as singularities of the EOG signal, based on wavelet methodology. The distribution of wakefulness, non-REM (NREM) sleep and rapid eye movement (REM) sleep was typical of nocturnal rodents with small amounts of wakefulness and large amounts of NREM sleep during the light period and reversed proportions during the dark period. REM sleep was distributed correspondingly. REM density was significantly higher during REM sleep than NREM sleep. REM bursts were detected more often at the end of the dark period than the beginning of the light period. During REM sleep REM density showed an ultradian course, and during NREM sleep REM density peaked at the beginning of the dark period. Concerning individual eye movements, REM duration was longer and amplitude was lower during REM sleep than NREM sleep. The majority of single REM and REM bursts were associated with micro-arousals during NREM sleep, but not during REM sleep. Sleep-stage specific distributions of REM in mice correspond to human

  14. Rapid eye movements during sleep in mice: High trait-like stability qualifies rapid eye movement density for characterization of phenotypic variation in sleep patterns of rodents

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    Fulda Stephany

    2011-11-01

    Full Text Available Abstract Background In humans, rapid eye movements (REM density during REM sleep plays a prominent role in psychiatric diseases. Especially in depression, an increased REM density is a vulnerability marker for depression. In clinical practice and research measurement of REM density is highly standardized. In basic animal research, almost no tools are available to obtain and systematically evaluate eye movement data, although, this would create increased comparability between human and animal sleep studies. Methods We obtained standardized electroencephalographic (EEG, electromyographic (EMG and electrooculographic (EOG signals from freely behaving mice. EOG electrodes were bilaterally and chronically implanted with placement of the electrodes directly between the musculus rectus superior and musculus rectus lateralis. After recovery, EEG, EMG and EOG signals were obtained for four days. Subsequent to the implantation process, we developed and validated an Eye Movement scoring in Mice Algorithm (EMMA to detect REM as singularities of the EOG signal, based on wavelet methodology. Results The distribution of wakefulness, non-REM (NREM sleep and rapid eye movement (REM sleep was typical of nocturnal rodents with small amounts of wakefulness and large amounts of NREM sleep during the light period and reversed proportions during the dark period. REM sleep was distributed correspondingly. REM density was significantly higher during REM sleep than NREM sleep. REM bursts were detected more often at the end of the dark period than the beginning of the light period. During REM sleep REM density showed an ultradian course, and during NREM sleep REM density peaked at the beginning of the dark period. Concerning individual eye movements, REM duration was longer and amplitude was lower during REM sleep than NREM sleep. The majority of single REM and REM bursts were associated with micro-arousals during NREM sleep, but not during REM sleep. Conclusions Sleep

  15. Three-Dimensional Eye Position Signals Shape Both Peripersonal Space and Arm Movement Activity in the Medial Posterior Parietal Cortex.

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    Kostas eHadjidimitrakis

    2012-06-01

    Full Text Available Research conducted over the last decades has established that the medial part of posterior parietal cortex is crucial for controlling visually guided actions in human and non-human primates. Within this cortical sector there is area V6A, a crucial node of the parietofrontal network involved in arm movement control in both monkeys and humans. However, the encoding of action-in-depth by V6A cells had been not studied till recently. Recent neurophysiological studies show the existence in V6A neurons of signals related to the distance of targets from the eyes. These signals are integrated, often at the level of single cells, with information about the direction of gaze, thus encoding spatial location in 3D space. Moreover, 3D eye position signals seem to be further exploited at two additional levels of neural processing: a in determining whether targets are located in the peripersonal space or not, and b in shaping the spatial tuning of arm movement related activity towards reachable targets. These findings are in line with studies in putative homolog regions in humans and together point to a role of medial posterior parietal cortex in encoding both the vergence angle of the eyes and peripersonal space. Besides this role in spatial encoding also in depth, several findings demonstrate the involvement of this cortical sector in non-spatial processes.

  16. [A rapid detection of motor block in patients with Parkinson disease during volitional movements of the hand].

    Science.gov (United States)

    Popović, Mirjana B; Kostić, Vladimir; Dzoljić, Eleonora; Ercegovac, Marko

    2002-01-01

    -15%; 5.5% had MBT% 15-20% and 2% had MBT% 20-25%. No block lasted more than 25% from the whole movement duration. Table 2 is the summary of mean variability for kinematic indicators of motor block (N, mbt%, t%) and for the movement duration T during a 7 day-testing of patients #3. The analysis of calculated data for eight tested PD patients revealed a significant difference (p evaluation of PD patients during their clinical evaluation and treatment. It provides to clinician a rapid feedback on the changes of voluntary hand movements in everyday progress of illness. Furthermore, this method could be of assistance for developing strategies to overcome motor blocks in arm movements at their beginning, as well as for the feedback of the success of drug therapy.

  17. Pacing the phasing of leg and arm movements in breaststroke swimming to minimize intra-cyclic velocity fluctuations.

    Science.gov (United States)

    van Houwelingen, Josje; Roerdink, Melvyn; Huibers, Alja V; Evers, Lotte L W; Beek, Peter J

    2017-01-01

    In swimming propelling efficiency is partly determined by intra-cyclic velocity fluctuations. The higher these fluctuations are at a given average swimming velocity, the less efficient is the propulsion. This study explored whether the leg-arm coordination (i.e. phase relation ϕ) within the breaststroke cycle can be influenced with acoustic pacing, and whether the so induced changes are accompanied by changes in intra-cyclic velocity fluctuations. Twenty-six participants were asked to couple their propulsive leg and arm movements to a double-tone metronome beat and to keep their average swimming velocity constant over trials. The metronome imposed five different phase relations ϕi (90, 135, 180, 225 and 270°) of leg-arm coordination. Swimmers adjusted their technique under the influence of the metronome, but failed to comply to the velocity requirement for ϕ = 90 and 135°. For imposed ϕ = 180, 225 and 270°, the intra-cyclic velocity fluctuations increased with increasing ϕ, while average swimming velocity did not differ. This suggests that acoustic pacing may be used to adjust ϕ and thereby performance of breaststroke swimming given the dependence of propelling efficiency on ϕ.

  18. Rapid eye movement sleep behavioral events: a new marker for neurodegeneration in early Parkinson disease?

    Science.gov (United States)

    Sixel-Döring, Friederike; Trautmann, Ellen; Mollenhauer, Brit; Trenkwalder, Claudia

    2014-03-01

    To analyze potential markers in sleep for early recognition of neurodegenerative disease in newly diagnosed, unmedicated patients with Parkinson disease (PD) compared to controls. Videopolysomnography (vPSG) was available in 158 newly diagnosed, unmedicated patients with PD and 110 age-, sex-, and education-matched healthy controls (HC). Rapid eye movement (REM) sleep was analyzed for REM without atonia (RWA) and studied by review of time-synchronized video. Motor behaviors and/or vocalizations in REM sleep with a purposeful component other than comfort moves were identified as REM sleep behavioral events (RBE). Two or more events had to be present to be classified as "RBE positive." RBE subjects included rapid eye movement sleep behavior disorder (RBD) and non-RBD subjects based on the presence or absence of RWA > 18.2%. RBE were detected in 81 of 158 patients with de novo PD (51%) and 17 of 110 HC (15%) (P sleep (P = 0.002) and a higher periodic leg movements in sleep index (P = 0.022) compared to subjects without RBE. This first description of REM sleep behavioral events (RBE) shows it occurs more frequently in patients with de novo Parkinson disease (PD) than in healthy controls and may be an early sign of neurodegeneration and precede rapid eye movement sleep behavior disorder (RBD). There is no specific phenotype of PD associated with newly defined RBE or RBD at this early stage.

  19. Robotic arm

    Science.gov (United States)

    Kwech, Horst

    1989-04-18

    A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel.

  20. EEG source space analysis of the supervised factor analytic approach for the classification of multi-directional arm movement

    Science.gov (United States)

    Shenoy Handiru, Vikram; Vinod, A. P.; Guan, Cuntai

    2017-08-01

    Objective. In electroencephalography (EEG)-based brain-computer interface (BCI) systems for motor control tasks the conventional practice is to decode motor intentions by using scalp EEG. However, scalp EEG only reveals certain limited information about the complex tasks of movement with a higher degree of freedom. Therefore, our objective is to investigate the effectiveness of source-space EEG in extracting relevant features that discriminate arm movement in multiple directions. Approach. We have proposed a novel feature extraction algorithm based on supervised factor analysis that models the data from source-space EEG. To this end, we computed the features from the source dipoles confined to Brodmann areas of interest (BA4a, BA4p and BA6). Further, we embedded class-wise labels of multi-direction (multi-class) source-space EEG to an unsupervised factor analysis to make it into a supervised learning method. Main Results. Our approach provided an average decoding accuracy of 71% for the classification of hand movement in four orthogonal directions, that is significantly higher (>10%) than the classification accuracy obtained using state-of-the-art spatial pattern features in sensor space. Also, the group analysis on the spectral characteristics of source-space EEG indicates that the slow cortical potentials from a set of cortical source dipoles reveal discriminative information regarding the movement parameter, direction. Significance. This study presents evidence that low-frequency components in the source space play an important role in movement kinematics, and thus it may lead to new strategies for BCI-based neurorehabilitation.

  1. Active controlled muscles in numerical model of human arm for movement in two degrees of freedom

    NARCIS (Netherlands)

    Budziszewski, P.; Nunen, E. van; Mordaka, J.K.; Kȩdzior, K.

    2008-01-01

    This paper describes the development of numerical model of human upper extremity able to perform movements and stabilization tasks in two degrees of freedom as a result of muscle activation controlled by a PID-based controller. These tasks are defined by functions of specified angle for every degree

  2. Rapid eye movement sleep behavior disorder as an outlier detection problem

    DEFF Research Database (Denmark)

    Kempfner, Jacob; Sørensen, Gertrud Laura; Nikolic, M.

    2014-01-01

    OBJECTIVE: Idiopathic rapid eye movement (REM) sleep behavior disorder is a strong early marker of Parkinson's disease and is characterized by REM sleep without atonia and/or dream enactment. Because these measures are subject to individual interpretation, there is consequently need...... for quantitative methods to establish objective criteria. This study proposes a semiautomatic algorithm for the early detection of Parkinson's disease. This is achieved by distinguishing between normal REM sleep and REM sleep without atonia by considering muscle activity as an outlier detection problem. METHODS...... limb movements did only have a minor influence on the quantification of the muscle activity. Analysis of muscle activity during nonrapid eye movement sleep may improve the separation even further. Copyright © 2014 by the American Clinical Neurophysiology Society....

  3. Reliability of movement workspace measurements in a passive arm orthosis used in spinal cord injury rehabilitation

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    Rudhe Claudia

    2012-06-01

    Full Text Available Abstract Background Robotic and non-robotic training devices are increasingly being used in the rehabilitation of upper limb function in subjects with neurological disorders. As well as being used for training such devices can also provide ongoing assessments during the training sessions. Therefore, it is mandatory to understand the reliability and validity of such measurements when used in a clinical setting. The aim of this study was to evaluate the reliability of movement measures as assessed in the Armeo Spring system for the eventual application to the rehabilitation of patients suffering from cervical spinal cord injury (SCI. Methods Reliability (intra- and inter-rater reliability of the movement workspace (representing multiple ranges of movement and the influence of varying seating conditions (5 different chair conditions was assessed in twenty control subjects. In eight patients with cervical SCI the test-retest reliability (tested twice on the same day by the same rater was assessed as well as a correlation of the movement workspace to retrieve self-care items as scored by the spinal cord independence measure (SCIM 3. Results Analysis of workspace measures in control subjects revealed intra-class correlation coefficients (ICC ranging from 0.747 to 0.837 for the intra-rater reliability and from 0.661 to 0.855 for the inter-rater reliability. Test-retest analysis in SCI patients showed a similar high reliability with ICC = 0.858. Also the reliability of the movement workspace between different seating conditions was good with ICCs ranging from 0.844 to 0.915. The movement workspace correlated significantly with the SCIM3 self-care items (p  Conclusion The upper limb movement workspace measures assessed in the Armeo Spring device revealed fair to good clinical reliability. These findings suggest that measures retrieved from such a training device can be used to monitor changes in upper limb function over time. The correlation

  4. Research progress on the pathogenesis of rapid eye movement sleep behavior disorder and neurodegenerative diseases

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    Hai-yang JIANG

    2017-10-01

    Full Text Available Rapid eye movement sleep behavior disorder (RBD is a sleep disorder characterized by the disappearance of muscle relaxation and enacting one's dreams during rapid eye movement (REM, with most of the dreams being violent or aggressive. Prevalence of RBD, based on population, is 0.38%-2.01%, but it becomes much higher in patients with neurodegenerative diseases, especially α - synucleinopathies. RBD may herald the emergence of α-synucleinopathies by decades, thus it may be used as an effective early marker of neurodegenerative diseases. In this review, we summarized the progress on the pathogenesis of RBD and its relationship with neurodegenerative diseases. DOI: 10.3969/j.issn.1672-6731.2017.10.003

  5. A single-question screen for rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Postuma, Ronald B; Arnulf, Isabelle; Hogl, Birgit

    2012-01-01

    Idiopathic rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia that is an important risk factor for Parkinson's disease (PD) and Lewy body dementia. Its prevalence is unknown. One barrier to determining prevalence is that current screening tools are too long for large-scale epi......Idiopathic rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia that is an important risk factor for Parkinson's disease (PD) and Lewy body dementia. Its prevalence is unknown. One barrier to determining prevalence is that current screening tools are too long for large......-scale epidemiologic surveys. Therefore, we designed the REM Sleep Behavior Disorder Single-Question Screen (RBD1Q), a screening question for dream enactment with a simple yes/no response....

  6. Dream Anxiety in Patients with Rapid Eye Movement Dependent Obstructive Sleep Apnea Syndrome

    OpenAIRE

    Ece Yazla; Mustafa Bilici; Zerrin Pelin

    2017-01-01

    Aims: The aim of this study is to investigate the effect of the breathing disorders that arise during sleep and are predominantly observed in Rapid Eye Movement (REM) phase onto the dreams which have negative effects on daily life. While doing this, we also investigated differences between the REM dependent and non REM dependent obstructive sleep apnea syndrome groups in terms of some sociodemographic and clinical characteristics. Methods: Seventy patients who had got the diagnosis of obs...

  7. Apnea-Induced Rapid Eye Movement Sleep Disruption Impairs Human Spatial Navigational Memory

    OpenAIRE

    Varga, Andrew W.; Kishi, Akifumi; Mantua, Janna; Lim, Jason; Koushyk, Viachaslau; Leibert, David P.; Osorio, Ricardo S.; Rapoport, David M.; Ayappa, Indu

    2014-01-01

    Hippocampal electrophysiology and behavioral evidence support a role for sleep in spatial navigational memory, but the role of particular sleep stages is less clear. Although rodent models suggest the importance of rapid eye movement (REM) sleep in spatial navigational memory, a similar role for REM sleep has never been examined in humans. We recruited subjects with severe obstructive sleep apnea (OSA) who were well treated and adherent with continuous positive airway pressure (CPAP). Restric...

  8. Slow wave and rapid eye movement sleep deprivation: differing impacts on memory consolidation?

    OpenAIRE

    Solomons, Luke

    2016-01-01

    It has been debated whether different stages in the human sleep cycle preferentially mediate the consolidation of explicit and implicit memories, or whether all of the stages in succession are necessary for optimal consolidation. We investigated whether the selective deprivation of slow wave sleep (SWS) or rapid eye movement (REM) sleep over an entire night would have a specific effect on consolidation in explicit and implicit memory tasks. Participants had one control night of undisturbed sl...

  9. Arm positions and movement analysis that are used on the upper extremity in Bolu women dances

    OpenAIRE

    Nihal Ötken

    2011-01-01

    Folk dances are the cultural products that are created by the people and transferred from generation to generation. These cultural products have a very rich variety that differ from region to region, in terms of style and type. These differences are tight-knit with the past, civilization level, beliefs and traditions of a society which creates every dance. These differences also reveal themselves on elements, such as the movement styles used during the dance, dance forms, the accompanying mus...

  10. Context-dependence of Aimed Arm Movements: A Transitory or A Stable Phenomenon?

    Directory of Open Access Journals (Sweden)

    Benjamin Baak

    2014-10-01

    Full Text Available Previous work documented that grasping movements in a typical laboratory context differ widely from those in a more natural context. We evaluate whether this context-dependence changes with experience. Data from 48 subjects (24 female; 24.9 ± 2.7 years of age were (reanalyzed. They had participated in experimental blocks with externally triggered, purposeless and repetitive movements (context L, laboratory-like, and a block with self-initiated, ecologically valid movements embedded in a complex task (context E, everyday-like. Mechanical constraints on grasping were identical in both blocks. A global metric, representing context-dependence across multiple kinematic parameters, did not change appreciably across the 20 trials of a block. Furthermore, the metric was not affected by prior participation in the other block. We conclude that context-dependence of grasping is robust, i.e., it shows little influence of prior experience. This opens the avenue for within-subject designs on context-dependence, e.g., for clinical investigations. Keywords: Motor control, Prehension, Context-dependence, Serial order, Attunement

  11. The effects of arm movement on reaction time in patients with latent and active upper trapezius myofascial trigger point.

    Science.gov (United States)

    Yassin, Marzieh; Talebian, Saeed; Ebrahimi Takamjani, Ismail; Maroufi, Nader; Ahmadi, Amir; Sarrafzadeh, Javad; Emrani, Anita

    2015-01-01

    Myofascial pain syndrome is a significant source of mechanical pain. The aim of this study was to investigate the effects of arm movement on reaction time in females with latent and active upper trapezius myofascial trigger point. In this interventional study, a convenience sample of fifteen women with one active MTP, fifteen women with one latent MTP in the upper trapezius, and fifteen normal healthy women were participated. Participants were asked to stand for 10 seconds in an erect standing position. Muscle reaction times were recorded including anterior deltoid (AD), cervical paraspinal (CP) lumbar paraspinal (LP), both of upper trapezius (UT), sternocleidomastoid (SCM) and medial head of gastrocnemius (GcM). Participants were asked to flex their arms in response to a sound stimulus preceded by a warning sound stimulus. Data were analyzed using one-way ANOVA Test. There was significant differences in motor time and reaction time between active and control groups (ptime between active and passive groups except for UT without MTP and SCM (ptimes between latent MTP and control groups. Furthermore, there was no significant difference in premotor times between the three groups. The present study shows that patients with active MTP need more time to react to stimulus, but patients with latent MTP are similar to healthy subjects in the reaction time. Patients with active MTP had less compatibility with environmental stimulations, and they responded to a specific stimulation with variability in Surface Electromyography (SEMG).

  12. The effects of arm movement on reaction time in patients with latent and active upper trapezius myofascial trigger point

    Science.gov (United States)

    Yassin, Marzieh; Talebian, Saeed; Ebrahimi Takamjani, Ismail; Maroufi, Nader; Ahmadi, Amir; Sarrafzadeh, Javad; Emrani, Anita

    2015-01-01

    Background: Myofascial pain syndrome is a significant source of mechanical pain. The aim of this study was to investigate the effects of arm movement on reaction time in females with latent and active upper trapezius myofascial trigger point. Methods: In this interventional study, a convenience sample of fifteen women with one active MTP, fifteen women with one latent MTP in the upper trapezius, and fifteen normal healthy women were participated. Participants were asked to stand for 10 seconds in an erect standing position. Muscle reaction times were recorded including anterior deltoid (AD), cervical paraspinal (CP) lumbar paraspinal (LP), both of upper trapezius (UT), sternocleidomastoid (SCM) and medial head of gastrocnemius (GcM). Participants were asked to flex their arms in response to a sound stimulus preceded by a warning sound stimulus. Data were analyzed using one-way ANOVA Test. Results: There was significant differences in motor time and reaction time between active and control groups (pactive and passive groups except for UT without MTP and SCM (platent MTP and control groups. Furthermore, there was no significant difference in premotor times between the three groups. Conclusion: The present study shows that patients with active MTP need more time to react to stimulus, but patients with latent MTP are similar to healthy subjects in the reaction time. Patients with active MTP had less compatibility with environmental stimulations, and they responded to a specific stimulation with variability in Surface Electromyography (SEMG). PMID:26913258

  13. Effects of neck flexion on discriminative and cognitive processing in anticipatory postural control during bilateral arm movement.

    Science.gov (United States)

    Fujiwara, Katsuo; Yaguchi, Chie; Kunita, Kenji; Mammadova, Aida

    2012-06-19

    We investigated the effect of neck flexion on discriminative and cognitive processing in postural control during bilateral arm movement while standing, using event-related potential (ERP) and electromyogram. Fourteen healthy subjects flexed their arms to the target stimuli with a 20% probability in neck resting and flexion positions. Amplitude and latency of N2 and P3, anterior deltoid (AD) reaction time, onset time of postural muscles with respect to AD activation, and peak amplitude and latency of all muscles were measured. With neck flexion, N2 and P3 amplitudes increased, N2 and P3 latencies and AD reaction time shortened, and onset times of all postural muscles became earlier. No significant differences in peak amplitude and latency of each muscle were found between neck positions. Significant positive correlations were found in changes with neck flexion between P3 latency and AD reaction time, and between N2 latency and onset time of erector spinae. These suggest that with neck flexion, attention allocation to discriminative and cognitive processing increased, and the processing speed increased with shortening of reaction time in focal muscles. In addition, the onset time of postural muscles became earlier without changing the activation pattern, which was associated with the hastened discriminative processing. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  14. Rapid change in articulatory lip movement induced by preceding auditory feedback during production of bilabial plosives.

    Science.gov (United States)

    Mochida, Takemi; Gomi, Hiroaki; Kashino, Makio

    2010-11-08

    There has been plentiful evidence of kinesthetically induced rapid compensation for unanticipated perturbation in speech articulatory movements. However, the role of auditory information in stabilizing articulation has been little studied except for the control of voice fundamental frequency, voice amplitude and vowel formant frequencies. Although the influence of auditory information on the articulatory control process is evident in unintended speech errors caused by delayed auditory feedback, the direct and immediate effect of auditory alteration on the movements of articulators has not been clarified. This work examined whether temporal changes in the auditory feedback of bilabial plosives immediately affects the subsequent lip movement. We conducted experiments with an auditory feedback alteration system that enabled us to replace or block speech sounds in real time. Participants were asked to produce the syllable /pa/ repeatedly at a constant rate. During the repetition, normal auditory feedback was interrupted, and one of three pre-recorded syllables /pa/, /Φa/, or /pi/, spoken by the same participant, was presented once at a different timing from the anticipated production onset, while no feedback was presented for subsequent repetitions. Comparisons of the labial distance trajectories under altered and normal feedback conditions indicated that the movement quickened during the short period immediately after the alteration onset, when /pa/ was presented 50 ms before the expected timing. Such change was not significant under other feedback conditions we tested. The earlier articulation rapidly induced by the progressive auditory input suggests that a compensatory mechanism helps to maintain a constant speech rate by detecting errors between the internally predicted and actually provided auditory information associated with self movement. The timing- and context-dependent effects of feedback alteration suggest that the sensory error detection works in a

  15. Rapid change in articulatory lip movement induced by preceding auditory feedback during production of bilabial plosives.

    Directory of Open Access Journals (Sweden)

    Takemi Mochida

    Full Text Available BACKGROUND: There has been plentiful evidence of kinesthetically induced rapid compensation for unanticipated perturbation in speech articulatory movements. However, the role of auditory information in stabilizing articulation has been little studied except for the control of voice fundamental frequency, voice amplitude and vowel formant frequencies. Although the influence of auditory information on the articulatory control process is evident in unintended speech errors caused by delayed auditory feedback, the direct and immediate effect of auditory alteration on the movements of articulators has not been clarified. METHODOLOGY/PRINCIPAL FINDINGS: This work examined whether temporal changes in the auditory feedback of bilabial plosives immediately affects the subsequent lip movement. We conducted experiments with an auditory feedback alteration system that enabled us to replace or block speech sounds in real time. Participants were asked to produce the syllable /pa/ repeatedly at a constant rate. During the repetition, normal auditory feedback was interrupted, and one of three pre-recorded syllables /pa/, /Φa/, or /pi/, spoken by the same participant, was presented once at a different timing from the anticipated production onset, while no feedback was presented for subsequent repetitions. Comparisons of the labial distance trajectories under altered and normal feedback conditions indicated that the movement quickened during the short period immediately after the alteration onset, when /pa/ was presented 50 ms before the expected timing. Such change was not significant under other feedback conditions we tested. CONCLUSIONS/SIGNIFICANCE: The earlier articulation rapidly induced by the progressive auditory input suggests that a compensatory mechanism helps to maintain a constant speech rate by detecting errors between the internally predicted and actually provided auditory information associated with self movement. The timing- and context

  16. Intervention to enhance skilled arm and hand movements after stroke: A feasibility study using a new virtual reality system

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    McLaughlin Margaret

    2007-06-01

    Full Text Available Abstract Background Rehabilitation programs designed to develop skill in upper extremity (UE function after stroke require progressive practice that engage and challenge the learner. Virtual realty (VR provides a unique environment where the presentation of stimuli can be controlled systematically for optimal challenge by adapting task difficulty as performance improves. We describe four VR tasks that were developed and tested to improve arm and hand movement skills for individuals with hemiparesis. Methods Two participants with chronic post-stroke paresis and different levels of motor severity attended 12 training sessions lasting 1 to 2 hours each over a 3-week period. Behavior measures and questionnaires were administered pre-, mid-, and post-training. Results Both participants improved VR task performance across sessions. The less impaired participant averaged more time on task, practiced a greater number of blocks per session, and progressed at a faster rate over sessions than the more impaired participant. Impairment level did not change but both participants improved functional ability after training. The less impaired participant increased the number of blocks moved on the Box & Blocks test while the more impaired participant achieved 4 more items on the Functional Test of the Hemiparetic UE. Conclusion Two participants with differing motor severity were able to engage in VR based practice and improve performance over 12 training sessions. We were able to successfully provide individualized, progressive practice based on each participant's level of movement ability and rate of performance improvement.

  17. Irom Chanu Sharmila and the Movement against Armed Forces Special Powers Act (AFSPA

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    Aparajita Sharma

    2014-02-01

    Full Text Available This paper, through the narratives of activists and Meira Paibis reiterates the slogan—repeal the Armed Forces Special Powers Act (AFSPA, which is draconian and anti-people in spirit. The atroci- ty, which has been meted out on the people of Manipur because of this Act, is a profound viola- tion of human rights. Rape, mindless killings, kidnapping, fake encounters have been normalised by virtue of this Act. The youths have been badly affected due to the conflict emerging out of this Act which treats people in Manipur as ‘objects’ against the imagined boundaries of the Indian na- tion-state for security from the neighbouring nations. In this process, the lived experiences of the people have been pushed to the periphery against the massive motive of the state to protect bor- ders and the imagined nation, which is a direct offshoot of the legacy of colonialism in India. The paper has tried to capture the history of Manipur on a capsule to concretise the struggle of Irom Sharmila and the ‘hopes’ she gives to the people of Manipur for ‘peace’ and ‘justice’. Alongside, it makes a humble attempt to describe the ‘life’ of Irom Sharmila. In addition, it describes the rage of Manipuris, which have given rise to insurgency asking for ‘freedom’ through various platforms.

  18. A 3-arm randomized controlled trial on the effects of dance movement intervention and exercises on elderly with early dementia.

    Science.gov (United States)

    Ho, Rainbow Tin Hung; Cheung, Jacob Kai Ki; Chan, Wai Chi; Cheung, Irene Kit Man; Lam, Linda Chiu Wah

    2015-10-19

    Dementia is characterized by a progressive decline and deterioration of brain regions such as memory, spatial navigation and language, along with disturbances in daily functioning. Non-pharmacological interventions that offer a holistic approach by targeting cognitive functioning, prognosis and the psychological and social effects of dementia require rigorous investigation. The well-established benefits of physical activity for cognitive functioning and psychological support in dementia have been observed with dance-movement intervention. There is substantial evidence that dance-movement interventions provide emotional and social advantages. Thus, a randomized controlled trial (RCT) is planned to investigate the positive effects of a dance movement intervention, compared with mild physical exercise, on the physical and psychological well-being of elderly Chinese individuals with early dementia. A 3-arm RCT with waitlist control design will be used in this study. Two hundred and one elderly participants with very mild to mild dementia will be screened and randomized into the following groups: (i) dance movement based intervention, (ii) stretching and exercise intervention and (iii) no intervention waitlist-control group. The two intervention groups will receive a 1-h intervention, twice a week, for 12 weeks. The participants will be assessed four times over the course of 12 months: baseline before randomization, post-intervention (3 months), 6 months from baseline and 12 months from baseline. The primary outcomes will be compared between assessment points and between groups on neuropsychiatric symptoms, psychosocial well-being and cognitive and daily functioning. Secondary outcomes will assess the changes in salivary cortisol levels and their relationships with the primary outcome measures. This study will provide substantial evidence of the efficacy of a dance-movement-based intervention in slowing down dementia progression, due to its ability to act as a

  19. Sensory Agreement Guides Kinetic Energy Optimization of Arm Movements during Object Manipulation.

    Directory of Open Access Journals (Sweden)

    Ali Farshchiansadegh

    2016-04-01

    Full Text Available The laws of physics establish the energetic efficiency of our movements. In some cases, like locomotion, the mechanics of the body dominate in determining the energetically optimal course of action. In other tasks, such as manipulation, energetic costs depend critically upon the variable properties of objects in the environment. Can the brain identify and follow energy-optimal motions when these motions require moving along unfamiliar trajectories? What feedback information is required for such optimal behavior to occur? To answer these questions, we asked participants to move their dominant hand between different positions while holding a virtual mechanical system with complex dynamics (a planar double pendulum. In this task, trajectories of minimum kinetic energy were along curvilinear paths. Our findings demonstrate that participants were capable of finding the energy-optimal paths, but only when provided with veridical visual and haptic information pertaining to the object, lacking which the trajectories were executed along rectilinear paths.

  20. A Hidden Markov Movement Model for rapidly identifying behavioral states from animal tracks

    DEFF Research Database (Denmark)

    Whoriskey, Kim; Auger-Méthé, Marie; Albertsen, Christoffer Moesgaard

    2017-01-01

    animal tracking data with significant measurement error, a Bayesian state-space model called the first-Difference Correlated Random Walk with Switching (DCRWS) has often been used for this purpose. However, for aquatic animals, highly accurate tracking data of animal movement are now becoming more common....... 2. We developed a new Hidden Markov Model (HMM) for identifying behavioral states from animal tracks with negligible error, which we called the Hidden Markov Movement Model (HMMM). We implemented as the basis for the HMMM the process equation of the DCRWS, but we used the method of maximum...... likelihood and the R package TMB for rapid model fitting. 3. We compared the HMMM to a modified version of the DCRWS for highly accurate tracks, the DCRWSnome, and to a common HMM for animal tracks fitted with the R package moveHMM. We show that the HMMM is both accurate and suitable for multiple species...

  1. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    and neurological disease. RBD is related to brainstem pathology. Furthermore, it is increasingly recognized that RBD is frequently related to Parkinsonian disorders and narcolepsy. This article reviews recent knowledge about RBD with focus on the diagnostic process and management.......Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...

  2. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...... and neurological disease. RBD is related to brainstem pathology. Furthermore, it is increasingly recognized that RBD is frequently related to Parkinsonian disorders and narcolepsy. This article reviews recent knowledge about RBD with focus on the diagnostic process and management....

  3. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical and neu...... and neurological disease. RBD is related to brainstem pathology. Furthermore, it is increasingly recognized that RBD is frequently related to Parkinsonian disorders and narcolepsy. This article reviews recent knowledge about RBD with focus on the diagnostic process and management....

  4. Rapid Eye Movements (REMs) and visual dream recall in both congenitally blind and sighted subjects

    OpenAIRE

    Bértolo, Helder; Mestre, Tiago; Barrio de Santos, Ana Rosa; Antona Peñalba, Beatriz

    2017-01-01

    Our objective was to evaluate rapid eye movements (REMs) associated with visual dream recall in sighted subjects and congenital blind. During two consecutive nights polysomnographic recordings were performed at subjects home. REMs were detected by visual inspection on both EOG channels (EOG-H, EOG-V) and further classified as occurring isolated or in bursts. Dream recall was defined by the existence of a dream report. The two groups were compared using t-test and also the two-way ANOVA and...

  5. Kinematic Outcome Measures using Target-Reaching Arm Movement in Stroke.

    Science.gov (United States)

    Yang, Qianqian; Yang, Yuan; Luo, Jie; Li, Le; Yan, Tiebin; Song, Rong

    2017-12-01

    This study aimed to quantitatively investigate upper extremity motor performance and disclose the abnormality of motor control induced by stroke. Ten patients and ten healthy subjects were instructed to perform target-reaching tasks at nine difficulty levels, and coordinates of the shoulder, elbow and tip of the index finger were recorded. Age-matched control performed significantly better than patients, as indicated by lower movement time (MT) and normalized jerk score (NJS) and higher peak velocity (V peak), percentage time to peak velocity (PTPV), fuzzy approximate entropy (fApEn) and relative joint angles correlation (RJAC); also, significant effects of difficulty on all parameters except RJAC and fApEn, were observed in two groups. There were significant correlations between PTPV and Fugl-Meyer assessment for upper extremity (FMA-UE) and between RJAC and FMA-UE at certain difficulty levels. The stroke-related differences could be explained by the increase in intrinsic neuromotor noise, and the difficulty-related differences may be related to extrinsic neuromotor noise. The increase in either noises could result in a degradation in motor control. The significant linear relationships between some kinematic parameters and the clinical score suggested that the kinematic parameters could be applied as quantitative outcome measures in the clinic in the future.

  6. Choice reaching with a LEGO arm robot (CoRLEGO): The motor system guides visual attention to movement-relevant information.

    Science.gov (United States)

    Strauss, Soeren; Woodgate, Philip J W; Sami, Saber A; Heinke, Dietmar

    2015-12-01

    We present an extension of a neurobiologically inspired robotics model, termed CoRLEGO (Choice reaching with a LEGO arm robot). CoRLEGO models experimental evidence from choice reaching tasks (CRT). In a CRT participants are asked to rapidly reach and touch an item presented on the screen. These experiments show that non-target items can divert the reaching movement away from the ideal trajectory to the target item. This is seen as evidence attentional selection of reaching targets can leak into the motor system. Using competitive target selection and topological representations of motor parameters (dynamic neural fields) CoRLEGO is able to mimic this leakage effect. Furthermore if the reaching target is determined by its colour oddity (i.e. a green square among red squares or vice versa), the reaching trajectories become straighter with repetitions of the target colour (colour streaks). This colour priming effect can also be modelled with CoRLEGO. The paper also presents an extension of CoRLEGO. This extension mimics findings that transcranial direct current stimulation (tDCS) over the motor cortex modulates the colour priming effect (Woodgate et al., 2015). The results with the new CoRLEGO suggest that feedback connections from the motor system to the brain's attentional system (parietal cortex) guide visual attention to extract movement-relevant information (i.e. colour) from visual stimuli. This paper adds to growing evidence that there is a close interaction between the motor system and the attention system. This evidence contradicts the traditional conceptualization of the motor system as the endpoint of a serial chain of processing stages. At the end of the paper we discuss CoRLEGO's predictions and also lessons for neurobiologically inspired robotics emerging from this work. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  7. Shared bimanual tasks elicit bimanual reflexes during movement.

    Science.gov (United States)

    Mutha, Pratik K; Sainburg, Robert L

    2009-12-01

    Previous research has suggested distinct predictive and reactive control mechanisms for bimanual movements compared with unimanual motion. Recent studies have extended these findings by demonstrating that movement corrections during bimanual movements might differ depending on whether or not the task is shared between the arms. We hypothesized that corrective responses during shared bimanual tasks recruit bilateral rapid feedback mechanisms such as reflexes. We tested this hypothesis by perturbing one arm as subjects performed uni- and bimanual movements. Movements were made in a virtual-reality environment in which hand position was displayed as a cursor on a screen. During bimanual motion, we provided cursor feedback either independently for each arm (independent-cursor) or such that one cursor was placed at the average location between the arms (shared-cursor). On random trials, we applied a 40 N force pulse to the right arm 100 ms after movement onset. Our results show that while reflex responses were rapidly elicited in the perturbed arm, electromyographic activity remained close to baseline levels in the unperturbed arm during the independent-cursor trials. In contrast, when the cursor was shared between the arms, reflex responses were reduced in the perturbed arm and were rapidly elicited in the unperturbed arm. Our results thus suggest that when both arms contribute to achieving the task goal, reflex responses are bilaterally elicited in response to unilateral perturbations. These results agree with and extend recent suggestions that bimanual feedback control might be modified depending on task context.

  8. Keeping still doesn't "make sense": examining a role for movement variability by stabilizing the arm during a postural control task.

    Science.gov (United States)

    Murnaghan, Chantelle D; Carpenter, Mark G; Chua, Romeo; Inglis, J Timothy

    2017-02-01

    Small-amplitude, higher frequency oscillations of the body or limb are typically observed when humans attempt to maintain the position of a body or limb in space. Recent investigations have suggested that these involuntary movements of the body during stance could be used as an exploratory means of acquiring sensory information. In the present study, we wanted to determine whether a similar phenomenon would be observed in an upper limb postural task that does not involve whole body postural control. Participants were placed in a supine position with the arm pointing vertically and were asked to maintain the position of the limb in space with and without visual feedback. The wrist was attached to an apparatus that allowed the experimenter to stabilize or "lock" movements of the arm without the participants' awareness. When participants were "locked," the forces recorded predicted greater accelerations than those observed when the arm was freely moving with and without visual feedback. From unlocked to locked, angular accelerations increased in the eyes-closed condition and when participants were provided visual feedback of arm angular displacements. Irrespective of their origin, small displacements of the limb may be used as an exploratory means of acquiring sensory information from the surrounding environment.NEW & NOTEWORTHY The role of movement variability during a static limb position task is currently unknown. We tested whether variability remains in the absence of sensory-based error with an apparatus that stabilized the limb without the participant's knowledge during a static postural task. Increased forces observed during arm stabilization predicted movements greater than those observed when not externally stabilized. These results suggest movement variability during static postures could facilitate the gathering of sensory information from the surrounding environment. Copyright © 2017 the American Physiological Society.

  9. Integration of gravitational torques in cerebellar pathways allows for the dynamic inverse computation of vertical pointing movements of a robot arm.

    Science.gov (United States)

    Gentili, Rodolphe J; Papaxanthis, Charalambos; Ebadzadeh, Mehdi; Eskiizmirliler, Selim; Ouanezar, Sofiane; Darlot, Christian

    2009-01-01

    Several authors suggested that gravitational forces are centrally represented in the brain for planning, control and sensorimotor predictions of movements. Furthermore, some studies proposed that the cerebellum computes the inverse dynamics (internal inverse model) whereas others suggested that it computes sensorimotor predictions (internal forward model). This study proposes a model of cerebellar pathways deduced from both biological and physical constraints. The model learns the dynamic inverse computation of the effect of gravitational torques from its sensorimotor predictions without calculating an explicit inverse computation. By using supervised learning, this model learns to control an anthropomorphic robot arm actuated by two antagonists McKibben artificial muscles. This was achieved by using internal parallel feedback loops containing neural networks which anticipate the sensorimotor consequences of the neural commands. The artificial neural networks architecture was similar to the large-scale connectivity of the cerebellar cortex. Movements in the sagittal plane were performed during three sessions combining different initial positions, amplitudes and directions of movements to vary the effects of the gravitational torques applied to the robotic arm. The results show that this model acquired an internal representation of the gravitational effects during vertical arm pointing movements. This is consistent with the proposal that the cerebellar cortex contains an internal representation of gravitational torques which is encoded through a learning process. Furthermore, this model suggests that the cerebellum performs the inverse dynamics computation based on sensorimotor predictions. This highlights the importance of sensorimotor predictions of gravitational torques acting on upper limb movements performed in the gravitational field.

  10. Modelling rapid mass movements using the shallow water equations in Cartesian coordinates

    Science.gov (United States)

    Hergarten, S.; Robl, J.

    2015-03-01

    We propose a new method to model rapid mass movements on complex topography using the shallow water equations in Cartesian coordinates. These equations are the widely used standard approximation for the flow of water in rivers and shallow lakes, but the main prerequisite for their application - an almost horizontal fluid table - is in general not satisfied for avalanches and debris flows in steep terrain. Therefore, we have developed appropriate correction terms for large topographic gradients. In this study we present the mathematical formulation of these correction terms and their implementation in the open-source flow solver GERRIS. This novel approach is evaluated by simulating avalanches on synthetic and finally natural topographies and the widely used Voellmy flow resistance law. Testing the results against analytical solutions and the proprietary avalanche model RAMMS, we found a very good agreement. As the GERRIS flow solver is freely available and open source, it can be easily extended by additional fluid models or source areas, making this model suitable for simulating several types of rapid mass movements. It therefore provides a valuable tool for assisting regional-scale natural hazard studies.

  11. Validation of the Turkish Version of the Rapid Eye Movement Sleep Behavior Disorder Questionnaire

    Science.gov (United States)

    Tarı Cömert, Itır; Pelin, Zerrin; Arıcak, Tolga; Yapan, Saadet

    2016-01-01

    The aim of this study was to assess the validity and reliability of a Turkish version of the rapid eye movement sleep behavior disorder questionnaire (the RBDSQ-T) for identifying patients with rapid eye movement sleep behavior disorder (RBD) and to ensure that this tool can be applied in Turkish language. Three groups were enrolled to validate the RBDSQ-T: 78 healthy controls, 17 patients previously diagnosed with RBD, and 28 patients with obstructive sleep apnea syndrome (OSAS). Based on a cut-off score of five, the RBDSQ-T was able to discriminate RBD patients from healthy controls with sensitivity of 100% and specificity of 87%. Accordingly, 63% of patients were correctly diagnosed using the RBDSQ-T. Similarly, with a cut-off score of five, the RBDSQ-T was able to discriminate RBD from OSAS with sensitivity of 100% and specificity of 64%. Assessment of test-retest reliability and internal consistency reliability using Kuder-Richardson 20 analysis revealed a test-retest correlation coefficient of 0.95 and a Kuder-Richardson 20 value of 0.82. The findings demonstrate that the RBDSQ-T is a valid and reliable tool. PMID:27340339

  12. Validation of the Turkish Version of the Rapid Eye Movement Sleep Behavior Disorder Questionnaire

    Directory of Open Access Journals (Sweden)

    Itır Tarı Cömert

    2016-01-01

    Full Text Available The aim of this study was to assess the validity and reliability of a Turkish version of the rapid eye movement sleep behavior disorder questionnaire (the RBDSQ-T for identifying patients with rapid eye movement sleep behavior disorder (RBD and to ensure that this tool can be applied in Turkish language. Three groups were enrolled to validate the RBDSQ-T: 78 healthy controls, 17 patients previously diagnosed with RBD, and 28 patients with obstructive sleep apnea syndrome (OSAS. Based on a cut-off score of five, the RBDSQ-T was able to discriminate RBD patients from healthy controls with sensitivity of 100% and specificity of 87%. Accordingly, 63% of patients were correctly diagnosed using the RBDSQ-T. Similarly, with a cut-off score of five, the RBDSQ-T was able to discriminate RBD from OSAS with sensitivity of 100% and specificity of 64%. Assessment of test-retest reliability and internal consistency reliability using Kuder-Richardson 20 analysis revealed a test-retest correlation coefficient of 0.95 and a Kuder-Richardson 20 value of 0.82. The findings demonstrate that the RBDSQ-T is a valid and reliable tool.

  13. Comparison between sEMG and force as control interfaces to support planar arm movements in adults with Duchenne: a feasibility study.

    Science.gov (United States)

    Lobo-Prat, Joan; Nizamis, Kostas; Janssen, Mariska M H P; Keemink, Arvid Q L; Veltink, Peter H; Koopman, Bart F J M; Stienen, Arno H A

    2017-07-12

    Adults with Duchenne muscular dystrophy (DMD) can benefit from devices that actively support their arm function. A critical component of such devices is the control interface as it is responsible for the human-machine interaction. Our previous work indicated that surface electromyography (sEMG) and force-based control with active gravity and joint-stiffness compensation were feasible solutions for the support of elbow movements (one degree of freedom). In this paper, we extend the evaluation of sEMG- and force-based control interfaces to simultaneous and proportional control of planar arm movements (two degrees of freedom). Three men with DMD (18-23 years-old) with different levels of arm function (i.e. Brooke scores of 4, 5 and 6) performed a series of line-tracing tasks over a tabletop surface using an experimental active arm support. The arm movements were controlled using three control methods: sEMG-based control, force-based control with stiffness compensation (FSC), and force-based control with no compensation (FNC). The movement performance was evaluated in terms of percentage of task completion, tracing error, smoothness and speed. For subject S1 (Brooke 4) FNC was the preferred method and performed better than FSC and sEMG. FNC was not usable for subject S2 (Brooke 5) and S3 (Brooke 6). Subject S2 presented significantly lower movement speed with sEMG than with FSC, yet he preferred sEMG since FSC was perceived to be too fatiguing. Subject S3 could not successfully use neither of the two force-based control methods, while with sEMG he could reach almost his entire workspace. Movement performance and subjective preference of the three control methods differed with the level of arm function of the participants. Our results indicate that all three control methods have to be considered in real applications, as they present complementary advantages and disadvantages. The fact that the two weaker subjects (S2 and S3) experienced the force-based control

  14. Long-Term Follow-up Investigation of Isolated Rapid Eye Movement Sleep Without Atonia Without Rapid Eye Movement Sleep Behavior Disorder: A Pilot Study.

    Science.gov (United States)

    Stefani, Ambra; Gabelia, David; Högl, Birgit; Mitterling, Thomas; Mahlknecht, Philipp; Stockner, Heike; Poewe, Werner; Frauscher, Birgit

    2015-11-15

    Idiopathic rapid eye movement (REM) sleep behavior disorder (RBD) is a harbinger of synuclein-mediated neurodegenerative diseases. It is unknown if this also applies to isolated REM sleep without atonia (RWA). We performed a long-term follow-up investigation of subjects with isolated RWA. Participants were recruited from 50 subjects with isolated RWA who were identified at the sleep laboratory of the Department of Neurology at the Medical University of Innsbruck between 2003 and 2005. Eligible subjects underwent follow-up clinical examination, polysomnography, and assessment of neurodegenerative biomarkers (cognitive impairment, finger speed deficit, impaired color vision, olfactory dysfunction, orthostatic hypotension, and substantia nigra hyperechogenicity). After a mean of 8.6 ± 0.9 y, 1 of 14 participating subjects (7.3%) progressed to RBD. Ten of 14 RWA subjects (71.4%) were positive for at least one neurodegenerative biomarker. Substantia nigra hyperechogenicity and presence of mild cognitive impairment were both present in 4 of 14 subjects with isolated RWA. Electromyographic activity measures increased significantly from baseline to follow-up polysomnography ("any" mentalis and both anterior tibialis muscles: 32.5 ± 9.4 versus 52.2 ± 16.6%; p = 0.004). This study provides first evidence that isolated RWA is an early biomarker of synuclein-mediated neurodegeneration. These results will have to be replicated in larger studies with longer observational periods. If confirmed, these disease findings have implications for defining at-risk cohorts for Parkinson disease. © 2015 American Academy of Sleep Medicine.

  15. Clinical characteristics, management and long-term outcome of suspected rapid eye movement sleep behaviour disorder in 14 dogs.

    Science.gov (United States)

    Schubert, T A; Chidester, R M; Chrisman, C L

    2011-02-01

    To describe the clinical characteristics, management and long-term outcome in dogs with suspected rapid eye movement sleep behaviour disorder. Medical records and video recordings of 14 dogs with suspected rapid eye movement sleep behaviour disorder were reviewed and the owners were contacted via telephone or email for further information. Clinical signs included episodes of violent limb movements, howling, barking, growling, chewing, or biting during sleep. Episodes occurred at night and during daytime naps. The age at onset ranged from 8 weeks to 7·5 years with a median of 6 years but 64% of dogs were one year or less. There was no apparent sex or breed predisposition. Rapid eye movement sleep behaviour disorder events were reduced in severity and frequency in 78% of the dogs treated with 40 mg/kg/day oral potassium bromide. One dog was euthanized within 3 months of the onset of signs because of their severity. The duration of the disorder in the 13 surviving dogs ranged from 1·5 to 9 years. None of the dogs spontaneously recovered. Rapid eye movement sleep behaviour disorder is suspected to occur in dogs, as it does in human beings. It causes concern to the owners and disrupts the home environment. Unlike human beings, rapid eye movement sleep behaviour disorder of dogs often has a juvenile onset. © 2011 British Small Animal Veterinary Association.

  16. Utility of optical facial feature and arm movement tracking systems to enable text communication in critically ill patients who cannot otherwise communicate.

    Science.gov (United States)

    Muthuswamy, M B; Thomas, B N; Williams, D; Dingley, J

    2014-09-01

    Patients recovering from critical illness especially those with critical illness related neuropathy, myopathy, or burns to face, arms and hands are often unable to communicate by writing, speech (due to tracheostomy) or lip reading. This may frustrate both patient and staff. Two low cost movement tracking systems based around a laptop webcam and a laser/optical gaming system sensor were utilised as control inputs for on-screen text creation software and both were evaluated as communication tools in volunteers. Two methods were used to control an on-screen cursor to create short sentences via an on-screen keyboard: (i) webcam-based facial feature tracking, (ii) arm movement tracking by laser/camera gaming sensor and modified software. 16 volunteers with simulated tracheostomy and bandaged arms to simulate communication via gross movements of a burned limb, communicated 3 standard messages using each system (total 48 per system) in random sequence. Ten and 13 minor typographical errors occurred with each system respectively, however all messages were comprehensible. Speed of sentence formation ranged from 58 to 120s with the facial feature tracking system, and 60-160s with the arm movement tracking system. The average speed of sentence formation was 81s (range 58-120) and 104s (range 60-160) for facial feature and arm tracking systems respectively, (Pcommunication aids in patients in general and burns critical care units who cannot communicate by conventional means, due to the nature of their injuries. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  17. Eruption of a deep-sea mud volcano triggers rapid sediment movement.

    Science.gov (United States)

    Feseker, Tomas; Boetius, Antje; Wenzhöfer, Frank; Blandin, Jerome; Olu, Karine; Yoerger, Dana R; Camilli, Richard; German, Christopher R; de Beer, Dirk

    2014-11-11

    Submarine mud volcanoes are important sources of methane to the water column. However, the temporal variability of their mud and methane emissions is unknown. Methane emissions were previously proposed to result from a dynamic equilibrium between upward migration and consumption at the seabed by methane-consuming microbes. Here we show non-steady-state situations of vigorous mud movement that are revealed through variations in fluid flow, seabed temperature and seafloor bathymetry. Time series data for pressure, temperature, pH and seafloor photography were collected over 431 days using a benthic observatory at the active Håkon Mosby Mud Volcano. We documented 25 pulses of hot subsurface fluids, accompanied by eruptions that changed the landscape of the mud volcano. Four major events triggered rapid sediment uplift of more than a metre in height, substantial lateral flow of muds at average velocities of 0.4 m per day, and significant emissions of methane and CO₂ from the seafloor.

  18. Neuropeptide S mitigates spatial memory impairment induced by rapid eye movement sleep deprivation in rats.

    Science.gov (United States)

    Zhao, Zhengqing; Huang, Liuqing; Wu, Huijuan; Li, Yanpeng; Zhang, Lin; Yin, You; Xiang, Zhenghua; Zhao, Zhongxin

    2010-06-23

    Rapid eye movement (REM) sleep deprivation causes learning and memory deficits. Neuropeptide S, a newly discovered neuropeptide, has been shown to regulate arousal, anxiety, and may enhance long-term memory formation and spatial memory. However, it is unknown whether neuropeptide S could improve the REM sleep deprivation-induced memory impairment. Here, we report that 72-h REM sleep deprivation in rats resulted in spatial memory impairment and reduced phosphorylation level of cAMP-response element binding protein in the hippocampus, both of which were reversed by central administration of neuropeptide S. The results suggest that neuropeptide S mitigates spatial memory impairment in rats induced by 72-h REM sleep deprivation, possibly through activating cAMP-response element binding protein phosphorylation in the hippocampus.

  19. The 'scanning hypothesis' of rapid eye movements during REM sleep: a review of the evidence.

    Science.gov (United States)

    Arnulf, I

    2011-12-01

    Rapid eye movements (REMs) and visual dreams are salient features of REM sleep. However, it is unclear whether the eyes scan dream images. Several lines of evidence oppose the scanning hypothesis: REMs persist in animals and humans without sight (pontine cats, foetus, neonates, born-blinds), some binocular REMs are not conjugated (no focus point), REMs occur in parallel (not in series) with the stimulation of the visual cortex by ponto-geniculo-occipital spikes, and visual dreams can be obtained in non REM sleep. Studies that retrospectively compared the direction of REMs to dream recall recorded after having awakened the sleeper yielded inconsistent results, with a concordance varying from 9 to 80%. However, this method was subject to methodological flaws, including the bias of retrospection and neck atonia that does not allow the determination of the exact direction of gaze. Using the model of RBD (in which patients are able to enact their dreams due to the absence of muscle atonia) in 56 patients, we directly determined if the eyes moved in the same directions as the head and limbs. When REMs accompanied goal-oriented motor behaviour during RBD (e.g., framing something, greeting with the hand, climbing a ladder), 90% were directed towards the action of the patient (same plane and direction). REMs were however absent in 38% of goal-oriented behaviours. This directional coherence between limbs, head and eye movements during RBD suggests that, when present, REMs imitate the scanning of the dream scene. Because REMs index and complexity were similar in patients with RBD and controls, this concordance can be extended to normal REM sleep. These results are consistent with the model of a brainstem generator activating simultaneously images, sounds, limbs movements and REMs in a coordinated parallel manner, as in a virtual reality.

  20. Rapid Eye Movements (REMs) and visual dream recall in both congenitally blind and sighted subjects

    Science.gov (United States)

    Bértolo, Helder; Mestre, Tiago; Barrio, Ana; Antona, Beatriz

    2017-08-01

    Our objective was to evaluate rapid eye movements (REMs) associated with visual dream recall in sighted subjects and congenital blind. During two consecutive nights polysomnographic recordings were performed at subjects home. REMs were detected by visual inspection on both EOG channels (EOG-H, EOG-V) and further classified as occurring isolated or in bursts. Dream recall was defined by the existence of a dream report. The two groups were compared using t-test and also the two-way ANOVA and a post-hoc Fisher test (for the features diagnosis (blind vs. sighted) and dream recall (yes or no) as a function of time). The average of REM awakenings per subject and the recall ability were identical in both groups. CB had a lower REM density than CS; the same applied to REM bursts and isolated eye movements. In the two-way ANOVA, REM bursts and REM density were significantly different for positive dream recall, mainly for the CB group and for diagnosis; furthermore for both features significant results were obtained for the interaction of time, recall and diagnosis; the interaction of recall and time was however, stronger. In line with previous findings the data show that blind have lower REMs density. However the ability of dream recall in congenitally blind and sighted controls is identical. In both groups visual dream recall is associated with an increase in REM bursts and density. REM bursts also show differences in the temporal profile. REM visual dream recall is associated with increased REMs activity.

  1. Memory Reactivation during Rapid Eye Movement Sleep Promotes Its Generalization and Integration in Cortical Stores

    Science.gov (United States)

    Sterpenich, Virginie; Schmidt, Christina; Albouy, Geneviève; Matarazzo, Luca; Vanhaudenhuyse, Audrey; Boveroux, Pierre; Degueldre, Christian; Leclercq, Yves; Balteau, Evelyne; Collette, Fabienne; Luxen, André; Phillips, Christophe; Maquet, Pierre

    2014-01-01

    Study Objectives: Memory reactivation appears to be a fundamental process in memory consolidation. In this study we tested the influence of memory reactivation during rapid eye movement (REM) sleep on memory performance and brain responses at retrieval in healthy human participants. Participants: Fifty-six healthy subjects (28 women and 28 men, age [mean ± standard deviation]: 21.6 ± 2.2 y) participated in this functional magnetic resonance imaging (fMRI) study. Methods and Results: Auditory cues were associated with pictures of faces during their encoding. These memory cues delivered during REM sleep enhanced subsequent accurate recollections but also false recognitions. These results suggest that reactivated memories interacted with semantically related representations, and induced new creative associations, which subsequently reduced the distinction between new and previously encoded exemplars. Cues had no effect if presented during stage 2 sleep, or if they were not associated with faces during encoding. Functional magnetic resonance imaging revealed that following exposure to conditioned cues during REM sleep, responses to faces during retrieval were enhanced both in a visual area and in a cortical region of multisensory (auditory-visual) convergence. Conclusions: These results show that reactivating memories during REM sleep enhances cortical responses during retrieval, suggesting the integration of recent memories within cortical circuits, favoring the generalization and schematization of the information. Citation: Sterpenich V, Schmidt C, Albouy G, Matarazzo L, Vanhaudenhuyse A, Boveroux P, Degueldre C, Leclercq Y, Balteau E, Collette F, Luxen A, Phillips C, Maquet P. Memory reactivation during rapid eye movement sleep promotes its generalization and integration in cortical stores. SLEEP 2014;37(6):1061-1075. PMID:24882901

  2. Electroencephalographic findings related with mild cognitive impairment in idiopathic rapid eye movement sleep behavior disorder.

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    Sasai, Taeko; Matsuura, Masato; Inoue, Yuichi

    2013-12-01

    Mild cognitive impairment (MCI) and electroencephalographic (EEG) slowing have been reported as common findings of idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) and α-synucleinopathies. The objective of this study is to clarify the relation between MCI and physiological markers in iRBD. Cross-sectional study. Yoyogi Sleep Disorder Center. Thirty-one patients with iRBD including 17 younger patients with iRBD (younger than 70 y) and 17 control patients for the younger patients with iRBD. N/A. Montreal Cognitive Assessment (MoCA) and n-polysomnogram (PSG) were conducted of all participants. In patients with iRBD, the factors associated with MCI were explored among parameters of REM sleep without atonia (RWA), score of Sniffin' Sticks Test (threshold-discrimination-identification [TDI] score), RBD morbidity, and RBD severity evaluated with the Japanese version of the RBD questionnaire (RBDQ-JP). The younger iRBD group showed significantly lower alpha power during wake and lower MoCA score than the age-matched control group. MCI was detected in 13 of 17 patients (76.5%) on MoCA in this group. Among patients wtih iRBD, the MoCA score negatively correlated with age, proportion of slow wave sleep, TDI score, and EEG spectral power. Multiple regression analysis provided the following equation: MoCA score = 50.871-0.116*age -5.307*log (δ power during REM sleep) + 0.086*TDI score (R² = 0.598, P sleep), and 0.357 for TDI score (F = 9.900, P sleep and olfactory dysfunction, was revealed to be associated with cognitive decline in idiopathic rapid eye movement sleep behavior disorder.

  3. Integration of gravitational torques in cerebellar pathways allows for the dynamic inverse computation of vertical pointing movements of a robot arm.

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    Rodolphe J Gentili

    Full Text Available BACKGROUND: Several authors suggested that gravitational forces are centrally represented in the brain for planning, control and sensorimotor predictions of movements. Furthermore, some studies proposed that the cerebellum computes the inverse dynamics (internal inverse model whereas others suggested that it computes sensorimotor predictions (internal forward model. METHODOLOGY/PRINCIPAL FINDINGS: This study proposes a model of cerebellar pathways deduced from both biological and physical constraints. The model learns the dynamic inverse computation of the effect of gravitational torques from its sensorimotor predictions without calculating an explicit inverse computation. By using supervised learning, this model learns to control an anthropomorphic robot arm actuated by two antagonists McKibben artificial muscles. This was achieved by using internal parallel feedback loops containing neural networks which anticipate the sensorimotor consequences of the neural commands. The artificial neural networks architecture was similar to the large-scale connectivity of the cerebellar cortex. Movements in the sagittal plane were performed during three sessions combining different initial positions, amplitudes and directions of movements to vary the effects of the gravitational torques applied to the robotic arm. The results show that this model acquired an internal representation of the gravitational effects during vertical arm pointing movements. CONCLUSIONS/SIGNIFICANCE: This is consistent with the proposal that the cerebellar cortex contains an internal representation of gravitational torques which is encoded through a learning process. Furthermore, this model suggests that the cerebellum performs the inverse dynamics computation based on sensorimotor predictions. This highlights the importance of sensorimotor predictions of gravitational torques acting on upper limb movements performed in the gravitational field.

  4. Quantitative assessment of motor speech abnormalities in idiopathic rapid eye movement sleep behaviour disorder.

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    Rusz, Jan; Hlavnička, Jan; Tykalová, Tereza; Bušková, Jitka; Ulmanová, Olga; Růžička, Evžen; Šonka, Karel

    2016-03-01

    Patients with idiopathic rapid eye movement sleep behaviour disorder (RBD) are at substantial risk for developing Parkinson's disease (PD) or related neurodegenerative disorders. Speech is an important indicator of motor function and movement coordination, and therefore may be an extremely sensitive early marker of changes due to prodromal neurodegeneration. Speech data were acquired from 16 RBD subjects and 16 age- and sex-matched healthy control subjects. Objective acoustic assessment of 15 speech dimensions representing various phonatory, articulatory, and prosodic deviations was performed. Statistical models were applied to characterise speech disorders in RBD and to estimate sensitivity and specificity in differentiating between RBD and control subjects. Some form of speech impairment was revealed in 88% of RBD subjects. Articulatory deficits were the most prominent findings in RBD. In comparison to controls, the RBD group showed significant alterations in irregular alternating motion rates (p = 0.009) and articulatory decay (p = 0.01). The combination of four distinctive speech dimensions, including aperiodicity, irregular alternating motion rates, articulatory decay, and dysfluency, led to 96% sensitivity and 79% specificity in discriminating between RBD and control subjects. Speech impairment was significantly more pronounced in RBD subjects with the motor score of the Unified Parkinson's Disease Rating Scale greater than 4 points when compared to other RBD individuals. Simple quantitative speech motor measures may be suitable for the reliable detection of prodromal neurodegeneration in subjects with RBD, and therefore may provide important outcomes for future therapy trials. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Morning rapid eye movement sleep naps facilitate broad access to emotional semantic networks.

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    Carr, Michelle; Nielsen, Tore

    2015-03-01

    The goal of the study was to assess semantic priming to emotion and nonemotion cue words using a novel measure of associational breadth for participants who either took rapid eye movement (REM) or nonrapid eye movement (NREM) naps or who remained awake; assess relation of priming to REM sleep consolidation and REM sleep inertia effects. The associational breadth task was applied in both a priming condition, where cue-words were signaled to be memorized prior to sleep (primed), and a nonpriming condition, where cue words were not memorized (nonprimed). Cue words were either emotional (positive, negative) or nonemotional. Participants were randomly assigned to either an awake (WAKE) or a sleep condition, which was subsequently split into NREM or REM groups depending on stage at awakening. Hospital-based sleep laboratory. Fifty-eight healthy participants (22 male) ages 18 to 35 y (Mage = 23.3 ± 4.08 y). The REM group scored higher than the NREM or WAKE groups on primed, but not nonprimed emotional cue words; the effect was stronger for positive than for negative cue words. However, REM time and percent correlated negatively with degree of emotional priming. Priming occurred for REM awakenings but not for NREM awakenings, even when the latter sleep episodes contained some REM sleep. Associational breadth may be selectively consolidated during REM sleep for stimuli that have been tagged as important for future memory retrieval. That priming decreased with REM time and was higher only for REM sleep awakenings is consistent with two explanatory REM sleep processes: REM sleep consolidation serving emotional downregulation and REM sleep inertia. © 2015 Associated Professional Sleep Societies, LLC.

  6. The face arm speech test: does it encourage rapid recognition of important stroke warning symptoms?

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    Robinson, Thompson G; Reid, Ann; Haunton, Victoria Joanna; Wilson, Andrew; Naylor, A Ross

    2013-06-01

    To assess public knowledge of stroke and transient ischaemic attack symptoms, and awareness of the content of a recent national health campaign. Interviewer-administered questionnaire. Leicester, UK. 1300 members of a mixed urban/rural, multiethnic population that was sampled in public areas, places of work and schools. Knowledge of the terms 'stroke', 'stroke risk factors' and the 'FAST campaign'. Awareness of stroke symptoms, and ability to distinguish from non-stroke symptoms. 70% of the public surveyed were aware of the FAST campaign, with highest penetration in the female, older and white population. Overall, high levels of awareness of FAST symptoms (facial weakness 89%, arm weakness 83%, speech problems 91%) as warning signs of stroke were observed, though significantly lower levels were reported in the black and minority ethnic population. However, poor recognition of other important signs, including leg weakness (57%) and visual loss (44%) were seen, and significantly more men were likely to report non-specific symptoms as being associated with stroke. The survey has confirmed the effectiveness of the recent FAST campaign in raising public awareness of stroke and stroke warning signs, though poorest penetration was seen in the black and minority ethnic population. However, important stroke symptoms, including leg weakness and visual loss, were poorly recognised. This may lead to delays in presentation, specialist assessment and secondary prevention, and such stroke warning signs should be included in future public health campaigns.

  7. Study on rapid eye movement sleep behavior disorder in patients with Parkinson's disease at early stage

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    Hui-li ZOU

    2017-10-01

    Full Text Available Objective To investigate the incidence, occurrence time and electrophysiological characteristics of rapid eye movement behavior disorder (RBD in patients with early Parkinson's disease (PD, and the characteristics of motor symptoms and non . motor symtoms (NMS. Methods Sixty PD patients were divided into PD + RBD group (N = 42 and control group (N = 18 according to whether they were complicated with RBD or not. Unified Parkinson's Disease Rating Scale (UPDRSⅡ andⅢ, Hoehn-Yahr Stage, Montreal Cognitive Assessment (MoCA, Hamilton Anxiety Rating Scale (HAMA, Hamilton Depression Rating Scale (HAMD, RBD Screening Questionnaire (RBDSQ, Epworth Sleepiness Scale (ESS and polysomnography (PSG were used in 60 patients. Results Among 60 patients, 42 (70% were accompanied by RBD. PSG showed that PD + RBD patients mainly presented upper limb stretching and gripping, body twitching, laughing, shouting, cursing and other non.violent actions, except 2 cases presented violent actions, such as hitting, kicking, etc. In PD + RBD group, the age was older (P = 0.024, duration was longer (P = 0.000, and UPDRSⅡ (P = 0.005,UPDRSⅢ(P = 0.001, the scale values of Hoehn-Yahr Sotage 2 (P = 0.007, anxiety (P = 0.044 and depression (P = 0.001 ratio were all higher than control group. There were significant differences in density of mandible myoelectric activity (P = 0.000 and ratio of rapid eye movement (REM without atonia (P = 0.000 between 2 groups. In PD + RBD group, 16 patients (38.10% had symptoms of RBD, earlier than PD occurred 5.20 (3.91, 6.51 years. Conclusions PD patients with older age, longer duration, more severe motor symptoms and non?motor symptoms were more likely to be accompanied by RBD. The severity of RBD in PD patients accompanied with RBD is higher than that in PD without RBD. RBD may be the early manifestation of PD. PSG has important value in the diagnosis of PD with RBD. DOI: 10.3969/j.issn.1672-6731.2017.10.006

  8. Compensation or Restoration: Closed-Loop Feedback of Movement Quality for Assisted Reach-to-Grasp Exercises with a Multi-Joint Arm Exoskeleton.

    Science.gov (United States)

    Grimm, Florian; Naros, Georgios; Gharabaghi, Alireza

    2016-01-01

    Assistive technology allows for intensive practice and kinematic measurements during rehabilitation exercises. More recent approaches attach a gravity-compensating multi-joint exoskeleton to the upper extremity to facilitate task-oriented training in three-dimensional space with virtual reality feedback. The movement quality, however, is mostly captured through end-point measures that lack information on proximal inter-joint coordination. This limits the differentiation between compensation strategies and genuine restoration both during the exercise and in the course of rehabilitation. We extended in this proof-of-concept study a commercially available seven degree-of-freedom arm exoskeleton by using the real-time sensor data to display a three-dimensional multi-joint visualization of the user's arm. Ten healthy subjects and three severely affected chronic stroke patients performed reach-to-grasp exercises resembling activities of daily living assisted by the attached exoskeleton and received closed-loop online feedback of the three-dimensional movement in virtual reality. Patients in this pilot study differed significantly with regard to motor performance (accuracy, temporal efficiency, range of motion) and movement quality (proximal inter-joint coordination) from the healthy control group. In the course of 20 training and feedback sessions over 4 weeks, these pathological measures improved significantly toward the reference parameters of healthy participants. It was moreover feasible to capture the evolution of movement pattern kinematics of the shoulder and elbow and to quantify the individual degree of natural movement restoration for each patient. The virtual reality visualization and closed-loop feedback of joint-specific movement kinematics makes it possible to detect compensation strategies and may provide a tool to achieve the rehabilitation goals in accordance with the individual capacity for genuine functional restoration; a proposal that warrants

  9. Dynamic of arm’s micro movements of elite athlete in Olympic exercises Rapid Fire Pistol and Air Pistol

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    V.T. Pyatkov

    2017-04-01

    Full Text Available Purpose: to scientifically substantiate the method of contactless determination of athlete hand’s movements in Olympic exercises with pistol. Material: in the research we used the data of 37 elite athletes in exercise Air Pistol (n=32 and in exercise Rapid Fire Pistol (n=5. Registration of pistol projection’s quickness of movement in target area was realized with the help of computer system Scatt. In total we analyzed 3100 space-time parameters of athletes’ technical-tactic actions in finalizing phase of shooting cycle. Results: we tested innovative method of contactless measuring of athlete’s hand’s micro movements in finalizing phase of shooting cycle. We found uncontrolled deviations from optimal pistol pointing position in vertical, horizontal and sagittal planes. Quickness of athlete hand’s movements in shooting process was determined. Conclusions: we scientifically substantiated the method of contactless determination of athlete hand’s movements at a distance in Olympic exercises with pistol. Besides, we determined the dynamic of athlete’s hand micro movements in Olympic exercises Rapid Fire Pistol та Air Pistol.

  10. Suppression of interictal spikes during phasic rapid eye movement sleep: a quantitative stereo-electroencephalography study.

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    Campana, C; Zubler, F; Gibbs, S; de Carli, F; Proserpio, P; Rubino, A; Cossu, M; Tassi, L; Schindler, K; Nobili, L

    2017-10-01

    Tonic and phasic rapid eye movement (REM) sleep seem to represent two different brain states exerting different effects on epileptic activity. In particular, interictal spikes are suppressed strongly during phasic REM sleep. The reason for this effect is not understood completely. A different level of synchronization in phasic and tonic REM sleep has been postulated, yet never measured directly. Here we assessed the interictal spike rate across non-REM (NREM) sleep, phasic and tonic REM sleep in nine patients affected by drug resistant focal epilepsy: five with type II focal cortical dysplasia and four with hippocampal sclerosis. Moreover, we applied different quantitative measures to evaluate the level of synchronization at the local and global scale during phasic and tonic REM sleep. We found a lower spike rate in phasic REM sleep, both within and outside the seizure onset zone. This effect seems to be independent from the histopathological substrate and from the brain region, where epileptic activity is produced (temporal versus extra-temporal). A higher level of synchronization was observed during tonic REM sleep both on a large (global) and small (local) spatial scale. Phasic REM sleep appears to be an interesting model for understanding the mechanisms of suppression of epileptic activity. © 2017 European Sleep Research Society.

  11. Rapid Eye Movement Sleep Behavior Disorder: A Review of the Literature and Update on Current Concepts.

    Science.gov (United States)

    Rodriguez, Carlos L; Jaimchariyatam, Nattapong; Budur, Kumar

    2017-09-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by abnormal behaviors emerging during REM sleep that may cause injury or sleep disruption. The diagnosis requires polysomnography (PSG) demonstrating a loss of normal skeletal muscle atonia during REM sleep. RBD results from dysfunction of the brain stem circuits responsible for maintaining normal REM sleep atonia and suppressing behaviors during REM sleep. The diagnosis of idiopathic RBD (IRBD), that is, RBD without an identifiable cause, is frequently followed years later by the development of a neurodegenerative disorder, most commonly one of the synucleinopathies. As such, RBD is often a step in the progression of a neurodegenerative disorder. In this circumstance, it is a manifestation of neurodegeneration occurring in the brain stem before spreading to adjacent and other CNS regions, resulting in the development of symptoms and signs that permit recognition of a specific neurodegenerative disorder. RBD has been linked with narcolepsy and has been associated with a variety of other disorders. The management of RBD focuses on preventive/safety measures, counseling, monitoring for the development of a neurodegenerative disorder, and pharmacotherapy, which is typically effective but not well understood. The purpose of this article is to review and update our current understanding of the clinical features, epidemiology, demographics, pathophysiology, evaluation, diagnosis, differential diagnosis, causes, associations, and the clinical management of RBD. Copyright © 2017. Published by Elsevier Inc.

  12. Impulse control disorder and rapid eye movement sleep behavior disorder in Parkinson's disease.

    Science.gov (United States)

    Bayard, Sophie; Dauvilliers, Yves; Yu, Huan; Croisier-Langenier, Muriel; Rossignol, Alexia; Charif, Mahmoud; Geny, Christian; Carlander, Bertrand; Cochen De Cock, Valérie

    2014-12-01

    The relationship between ICD and RBD is still not yet understood and the results from the current literature are contradictory in PD. We aimed to explore the association between rapid eye movement (REM) sleep behavior disorder (RBD) and impulse control disorder in Parkinson's disease. Ninety-eight non-demented patients with Parkinson's disease underwent one night of video-polysomnography recording. The diagnosis of RBD was established according to clinical and polysomnographic criteria. Impulse control disorders were determined by a gold standard, semi-structured diagnostic interview. Half of the patients (n = 49) reported clinical history of RBD while polysomnographic diagnosis of RBD was confirmed in 31.6% of the patients (n = 31). At least one impulse control disorder was identified in 21.4% of patients, 22.6% with RBD and 20.9% without. Logistic regression controlling for potential confounders indicated that both clinical RBD (OR = 0.34, 95% CI = 0.07-1.48, P = 0.15) and polysomnographic confirmed RBD diagnoses (OR = 0.1.28, 95% CI = 0.31-5.33, P = 0.34) were not associated with impulse control disorder. In Parkinson's disease, REM Sleep Behavior Disorder is not associated with impulse control disorder. The results of our study do not support the notion that PSG-confirmed RBD and ICD share a common pathophysiology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Longitudinal assessment of probable rapid eye movement sleep behaviour disorder in Parkinson's disease.

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    Bjørnarå, K A; Dietrichs, E; Toft, M

    2015-08-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is frequently present in patients with Parkinson's disease (PD) and may have prognostic implications. There are few longitudinal studies of RBD in patients with PD. Our aim was to investigate whether RBD was a persistent feature in a follow-up study of 107 patients with PD. After a mean follow-up time of 3 years, 96 patients were available for reassessment. Probable RBD (pRBD) was diagnosed by the REM sleep behaviour disorder screening questionnaire. At follow-up, pRBD was found in 49% of the patients, versus 38% at baseline. The pRBD status remained unchanged in three-quarters of the patients, whilst 17% had new pRBD symptoms. Disease duration was longer in the pRBD group, 9.4 vs. 7.6 years (P = 0.02). Probable RBD is a persistent feature in PD and probably increases over time. © 2015 EAN.

  14. Laughing as a manifestation of rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Siclari, F; Wienecke, M; Poryazova, R; Bassetti, C L; Baumann, C R

    2011-06-01

    Among the range of sleep-related behavior displayed by patients with rapid eye movement (REM) sleep behavior disorder (RBD), aggressive acts are particularly common, while pleasant behaviors have rarely been reported. We aimed at identifying the frequency and characteristics of patients who displayed laughing as a pleasant, nonviolent manifestation of RBD. We reviewed 67 consecutive polysomnographic recordings of patients with RBD, obtained in our sleep laboratory between July 2004 and July 2009. We identified 14 patients (21% of our RBD patients with degenerative parkinsonism: 10 males, mean age 63 ± 11 years) who repeatedly laughed during REM sleep. Ten patients had idiopathic Parkinson's disease, 3 suffered from multisystem atrophy and 1 patient was diagnosed with dementia with Lewy bodies. Other RBD-associated behaviors included smiling, crying, aggressive behavior, screaming, and somniloquia. Nine of the 14 patients were depressed during daytime. Laughing belongs to the spectrum of behavioral manifestations of RBD. Many of our patients with RBD-associated laughter were depressed, suggesting a dissociation between emotional expression during daytime and REM sleep. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Eruption of a deep-sea mud volcano triggers rapid sediment movement

    Science.gov (United States)

    Feseker, Tomas; Boetius, Antje; Wenzhöfer, Frank; Blandin, Jerome; Olu, Karine; Yoerger, Dana R.; Camilli, Richard; German, Christopher R.; de Beer, Dirk

    2014-01-01

    Submarine mud volcanoes are important sources of methane to the water column. However, the temporal variability of their mud and methane emissions is unknown. Methane emissions were previously proposed to result from a dynamic equilibrium between upward migration and consumption at the seabed by methane-consuming microbes. Here we show non-steady-state situations of vigorous mud movement that are revealed through variations in fluid flow, seabed temperature and seafloor bathymetry. Time series data for pressure, temperature, pH and seafloor photography were collected over 431 days using a benthic observatory at the active Håkon Mosby Mud Volcano. We documented 25 pulses of hot subsurface fluids, accompanied by eruptions that changed the landscape of the mud volcano. Four major events triggered rapid sediment uplift of more than a metre in height, substantial lateral flow of muds at average velocities of 0.4 m per day, and significant emissions of methane and CO2 from the seafloor. PMID:25384354

  16. Memory reactivation during rapid eye movement sleep promotes its generalization and integration in cortical stores.

    Science.gov (United States)

    Sterpenich, Virginie; Schmidt, Christina; Albouy, Geneviève; Matarazzo, Luca; Vanhaudenhuyse, Audrey; Boveroux, Pierre; Degueldre, Christian; Leclercq, Yves; Balteau, Evelyne; Collette, Fabienne; Luxen, André; Phillips, Christophe; Maquet, Pierre

    2014-06-01

    Memory reactivation appears to be a fundamental process in memory consolidation. In this study we tested the influence of memory reactivation during rapid eye movement (REM) sleep on memory performance and brain responses at retrieval in healthy human participants. Fifty-six healthy subjects (28 women and 28 men, age [mean ± standard deviation]: 21.6 ± 2.2 y) participated in this functional magnetic resonance imaging (fMRI) study. Auditory cues were associated with pictures of faces during their encoding. These memory cues delivered during REM sleep enhanced subsequent accurate recollections but also false recognitions. These results suggest that reactivated memories interacted with semantically related representations, and induced new creative associations, which subsequently reduced the distinction between new and previously encoded exemplars. Cues had no effect if presented during stage 2 sleep, or if they were not associated with faces during encoding. Functional magnetic resonance imaging revealed that following exposure to conditioned cues during REM sleep, responses to faces during retrieval were enhanced both in a visual area and in a cortical region of multisensory (auditory-visual) convergence. These results show that reactivating memories during REM sleep enhances cortical responses during retrieval, suggesting the integration of recent memories within cortical circuits, favoring the generalization and schematization of the information.

  17. A new function of rapid eye movement sleep: improvement of muscular efficiency.

    Science.gov (United States)

    Cai, Zi-Jian

    2015-05-15

    Previously I demonstrated that the slow wave sleep (SWS) functioned to adjust the emotional balance disrupted by emotional memories randomly accumulated during waking, while the rapid eye movement (REM) sleep played the opposite role. Many experimental results have unambiguously shown that various emotional memories are processed during REM sleep. In this article, it is attempted to combine this confirmed function of REM sleep with the atonic state unique to REM sleep, and to integrate a new theory suggesting that improvement of muscular efficiency be a new function of REM sleep. This new function of REM sleep is more advantageous than the function of REM sleep in emotional memories and disinhibited drives to account for the phylogenetic variations of REM sleep, especially the absence of REM sleep in dolphins and short duration of REM sleep in birds in contrary to that in humans and rodents, the absence of penile erections in REM sleep in armadillo, as well as the higher voltage in EEG during REM sleep in platypus and ostrich. Besides, this new function of REM sleep is also advantageous to explain the association of REM sleep with the atonic episodes in SWS, the absence of drastic menopausal change in duration of REM sleep, and the effects of ambient temperature on the duration of REM sleep. These comparative and experimental evidences support the improvement of muscular efficiency as a new and major function of REM sleep. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Neurophysiological basis of rapid eye movement sleep behavior disorder: informing future drug development

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    Jennum P

    2016-04-01

    Full Text Available Poul Jennum, Julie AE Christensen, Marielle Zoetmulder Department of Clinical Neurophysiology, Faculty of Health Sciences, Danish Center for Sleep Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark Abstract: Rapid eye movement (REM sleep behavior disorder (RBD is a parasomnia characterized by a history of recurrent nocturnal dream enactment behavior and loss of skeletal muscle atonia and increased phasic muscle activity during REM sleep: REM sleep without atonia. RBD and associated comorbidities have recently been identified as one of the most specific and potentially sensitive risk factors for later development of any of the alpha-synucleinopathies: Parkinson’s disease, dementia with Lewy bodies, and other atypical parkinsonian syndromes. Several other sleep-related abnormalities have recently been identified in patients with RBD/Parkinson’s disease who experience abnormalities in sleep electroencephalographic frequencies, sleep–wake transitions, wake and sleep stability, occurrence and morphology of sleep spindles, and electrooculography measures. These findings suggest a gradual involvement of the brainstem and other structures, which is in line with the gradual involvement known in these disorders. We propose that these findings may help identify biomarkers of individuals at high risk of subsequent conversion to parkinsonism. Keywords: motor control, brain stem, hypothalamus, hypocretin

  19. Rapid eye movement sleep behavior disorder in treatment-naïve Parkinson disease patients.

    Science.gov (United States)

    Plomhause, Lucie; Dujardin, Kathy; Duhamel, Alain; Delliaux, Marie; Derambure, Philippe; Defebvre, Luc; Monaca Charley, Christelle

    2013-10-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a risk factor for dementia in Parkinson disease (PD) patients. The objectives of our study were to prospectively evaluate the frequency of RBD in a sample of treatment-naïve, newly diagnosed PD patients and compare sleep characteristics and cognition in RBD and non-RBD groups. Fifty-seven newly diagnosed PD patients were consecutively recruited in a university medical center. All patients underwent two overnight polysomnography (PSG) sessions and were diagnosed with RBD according to the International Classification of Sleep Disorders, Second Revision criteria. Daytime sleepiness was measured in a multiple sleep latency test (MSLT). Cognition was assessed in a standard neuropsychologic examination. Seventeen PD patients (30%) met the criteria for RBD. The RBD patients and non-RBD patients did not significantly differ in mean age, gender ratio, disease duration, motor symptom subtype and severity, total sleep time, percentage of REM sleep, apnea-hypopnea index, mean oxygen saturation, and importantly cognitive performance. However, non-RBD patients had a significantly shorter mean daytime sleep latency than RBD patients (15 vs. 18 min, respectively; P=.014). A high frequency of RBD was found in our sample of 57 newly diagnosed PD patients. At this stage in the disease, RBD was not found to be associated with other sleep disorders or cognitive decline. Follow-up is needed to assess the risk for developing dementia in early-stage PD patients with RBD. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Perception of experimental pain is reduced after provoked waking from rapid eye movement sleep.

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    Daya, Vivek G; Bentley, Alison J

    2010-06-01

    Patients with chronic pain often complain of pain when they wake at night, but the accuracy of their perception of the pain after waking at night is unknown. While cognitive functions are reduced for a short time after waking from sleep, a situation known as sleep inertia, it is unclear how sleep inertia may affect the perception of pain. We investigated the effects of sleep inertia on the perception of experimentally induced pain. Fourteen male volunteers were exposed to a randomized thermal heat stimulus of 43.1 degrees C 'hot' and 46.5 degrees C 'hurting' during provoked waking from Stage 2 sleep, slow wave sleep and rapid eye movement (REM) sleep. Subjects rated their pain on awakening on a Visual Analogue Scale at 30 s after awakening and each minute thereafter for 5 min. We found no change in pain perception over the 5-min period irrespective of temperature used or sleep stage. However, perceived pain when awoken abruptly from REM sleep was significantly lower than the awake score for both the hot (P = 0.0069) and hurting (P = 0.0025) temperatures. Pain perception when woken from Stage 2 sleep or slow wave sleep was not significantly different from perception when awake. Our findings indicate that sleep inertia reduces pain perception when awoken abruptly from REM. This suggests that patients who wake up in pain either perceive accurately the pain they are experiencing, or at worst underestimate the level of pain if woken from REM sleep.

  1. Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?

    Science.gov (United States)

    Madan, Vibha; Jha, Sushil K

    2012-12-01

    Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement (REM) sleep state. During REM sleep, postural muscles become atonic and the temperature regulating machinery remains suspended. Although REM sleep is present in almost all the terrestrial mammals, the aquatic mammals have either radically reduced or completely eliminated REM sleep. Further, we found a significant negative correlation between REM sleep and the adaptation of the organism to live on land or in water. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals and completely absent or negligible in aquatic mammals. The aquatic mammals are obligate swimmers and have to surface at regular intervals for air. Also, these animals live in thermally challenging environments, where the conductive heat loss is approximately ~90 times greater than air. Therefore, they have to be moving most of the time. As an adaptation, they have evolved unihemispheric sleep, during which they can rove as well as rest. A condition that immobilizes muscle activity and suspends the thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals. It is possible that, in accord with Darwin's theory, aquatic mammals might have abolished REM sleep with time. In this review, we discuss the possibility of the intrinsic role of aquatic conditions in the elimination of REM sleep in the aquatic mammals.

  2. Rapid eye movement-sleep is reduced in patients with acute uncomplicated diverticulitis—an observational study

    Directory of Open Access Journals (Sweden)

    Chenxi Huang

    2015-08-01

    Full Text Available Introduction. Sleep disturbances are commonly found in patients in the postoperative period. Sleep disturbances may give rise to several complications including cardiopulmonary instability, transient cognitive dysfunction and prolonged convalescence. Many factors including host inflammatory responses are believed to cause postoperative sleep disturbances, as inflammatory responses can alter sleep architecture through cytokine-brain interactions. Our aim was to investigate alteration of sleep architecture during acute infection and its relationships to inflammation and clinical symptoms.Materials & Methods. In this observational study, we included patients with acute uncomplicated diverticulitis as a model to investigate the isolated effects of inflammatory responses on sleep. Eleven patients completed the study. Patients were admitted and treated with antibiotics for two nights, during which study endpoints were measured by polysomnography recordings, self-reported discomfort scores and blood samples of cytokines. One month later, the patients, who now were in complete remission, were readmitted and the endpoints were re-measured (the baseline values.Results. Total sleep time was reduced 4% and 7% the first (p = 0.006 and second (p = 0.014 nights of diverticulitis, compared to baseline, respectively. The rapid eye movement sleep was reduced 33% the first night (p = 0.016, compared to baseline. Moreover, plasma IL-6 levels were correlated to non-rapid eye movement sleep, rapid eye movement sleep and fatigue.Conclusion. Total sleep time and rapid eye movement sleep were reduced during nights with active diverticulitis and correlated with markers of inflammation.

  3. Improved orthopedic arm joint

    Science.gov (United States)

    Dane, D. H.

    1971-01-01

    Joint permits smooth and easy movement of disabled arm and is smaller, lighter and less expensive than previous models. Device is interchangeable and may be used on either arm at the shoulder or at the elbow.

  4. Mortality and Its Risk Factors in Patients with Rapid Eye Movement Sleep Behavior Disorder.

    Science.gov (United States)

    Zhou, Junying; Zhang, Jihui; Lam, Siu Ping; Mok, Vincent; Chan, Anne; Li, Shirley Xin; Liu, Yaping; Tang, Xiangdong; Yung, Wing Ho; Wing, Yun Kwok

    2016-08-01

    To determine the mortality and its risk factors in patients with rapid eye movement (REM) sleep behavior disorder (RBD). A total of 205 consecutive patients with video-polysomnography confirmed RBD (mean age = 66.4 ± 10.0 y, 78.5% males) were recruited. Medical records and death status were systematically reviewed in the computerized records of the health care system. Standardized mortality ratio (SMR) was used to calculate the risk ratio of mortality in RBD with reference to the general population. Forty-three patients (21.0%) died over a mean follow-up period of 7.1 ± 4.5 y. The SMR was not increased in the overall sample, SMR (95% confidence interval [CI]) = 1.00 (0.73-1.33). However, SMR (95% CI) increased to 1.80 (1.21-2.58) and 1.75 (1.11-2.63) for RBD patients in whom neurodegenerative diseases and dementia, respectively, eventually developed. In the Cox regression model, mortality risk was significantly associated with age (hazard ratio [HR] = 1.05; 95% CI, 1.01-1.10), living alone (HR = 2.04; 95% CI, 1.39-2.99), chronic obstructive pulmonary disease (HR = 3.38; 95% CI, 1.21-9.46), cancer (HR = 10.09; 95% CI, 2.65-38.42), periodic limb movements during sleep (HR = 3.06; 95% CI, 1.50-6.24), and development of neurodegenerative diseases (HR = 2.84; 95% CI, 1.47-5.45) and dementia (HR = 2.66; 95% CI, 1.39-5.08). Patients with RBD have a higher mortality rate than the general population only if neurodegenerative diseases develop. Several risk factors on clinical and sleep aspects are associated with mortality in RBD patients. Our findings underscore the necessity of timely neuroprotective interventions in the early phase of RBD before the development of neurodegenerative diseases. © 2016 Associated Professional Sleep Societies, LLC.

  5. Therapeutic synergism in the treatment of post-stroke arm paresis utilizing botulinum toxin, robotic therapy, and constraint-induced movement therapy.

    Science.gov (United States)

    Takebayashi, Takashi; Amano, Satoru; Hanada, Keisuke; Umeji, Atsushi; Takahashi, Kayoko; Koyama, Tetsuo; Domen, Kazuhisa

    2014-11-01

    Botulinum toxin type A (BtxA) injection, constraint-induced movement therapy (CIMT), and robotic therapy (RT) each represent promising approaches to enhance arm motor recovery after stroke. To provide more effective treatment for a 50-year-old man with severe left spastic hemiparesis, we attempted to facilitate CIMT with adaptive approaches to extend the wrist and fingers using RT for 10 consecutive weeks after BtxA injection. This combined treatment resulted in substantial improvements in arm function and the amount of arm use in activities of daily living, and may be effective for stroke patients with severe arm paresis. However, we were unable to sufficiently prove the efficacy of combined treatment based only on a single case. To fully elucidate the efficacy of the combined approach for patients with severe hemiparesis after stroke, future studies of a larger number of patients are needed. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  6. Rapid eye movement-sleep is reduced in patients with acute uncomplicated diverticulitis—an observational study

    DEFF Research Database (Denmark)

    Huang, Chenxi; Alamili, Mahdi; Nielsen, Claus Henrik

    2015-01-01

    responses are believed to cause postoperative sleep disturbances, as inflammatory responses can alter sleep architecture through cytokine-brain interactions. Our aim was to investigate alteration of sleep architecture during acute infection and its relationships to inflammation and clinical symptoms....... Materials & Methods. In this observational study, we included patients with acute uncomplicated diverticulitis as a model to investigate the isolated effects of inflammatory responses on sleep. Eleven patients completed the study. Patients were admitted and treated with antibiotics for two nights, during...... was reduced 4% and 7% the first (p = 0.006) and second (p = 0.014) nights of diverticulitis, compared to baseline, respectively. The rapid eye movement sleep was reduced 33% the first night (p = 0.016), compared to baseline. Moreover, plasma IL-6 levels were correlated to non-rapid eye movement sleep, rapid...

  7. Feedback Control of arm movements using Neuro-Muscular Electrical Stimulation (NMES combined with a lockable, passive exoskeleton for gravity compensation

    Directory of Open Access Journals (Sweden)

    Christian eKlauer

    2014-09-01

    Full Text Available Within the European project MUNDUS, an assistive framework was developed for the support of arm and hand functions during daily life activities in severely impaired people. Potential users of this system are patients with high-level spinal cord injury and neurodegenerative neuromuscular diseases, such as amyotrophic lateral sclerosis, Friedreich ataxia, and multiple sclerosis. This contribution aims at designing a feedback control system for Neuro-Muscular Electrical Stimulation (NMES to enable reaching functions in people with no residual voluntary control of the arm due to upper motor neuron lesions after spinal cord injury. NMES is applied to the deltoids and the biceps muscles and integrated with a three degrees of freedom (DoFs passive exoskeleton, which partially compensates gravitational forces and allows to lock each DOF. The user is able to choose the target hand position and to trigger actions using an eyetracker system. The target position is selected by using the eyetracker and determined by a marker-based tracking system using Microsoft Kinect. A central controller, i.e. a finite state machine, issues a sequence of basic movement commands to the real-time arm controller. The NMES control algorithm sequentially controls each joint angle while locking the other DoFs. Daily activities, such as drinking, brushing hair, pushing an alarm button, etc., can be supported by the system. The robust and easily tunable control approach was evaluated with five healthy subjects during a drinking task. Subjects were asked to remain passive and to allow NMES to induce the movements. In all of them, the controller was able to perform the task, and a mean hand positioning error of less than five centimeters was achieved. The average total time duration for moving the hand from a rest position to a drinking cup, for moving the cup to the mouth and back, and for finally returning the arm to the rest position was 71 seconds.

  8. Quantitative EEG of Rapid-Eye-Movement Sleep: A Marker of Amnestic Mild Cognitive Impairment.

    Science.gov (United States)

    Brayet, Pauline; Petit, Dominique; Frauscher, Birgit; Gagnon, Jean-François; Gosselin, Nadia; Gagnon, Katia; Rouleau, Isabelle; Montplaisir, Jacques

    2016-04-01

    The basal forebrain cholinergic system, which is impaired in early Alzheimer's disease, is more crucial for the activation of rapid-eye-movement (REM) sleep electroencephalogram (EEG) than it is for wakefulness. Quantitative EEG from REM sleep might thus provide an earlier and more accurate marker of the development of Alzheimer's disease in subjects with mild cognitive impairment (MCI) subjects than that from wakefulness. To assess the superiority of the REM sleep EEG as a screening tool for preclinical Alzheimer's disease, 22 subjects with amnestic MCI (a-MCI; 63.9±7.7 years), 10 subjects with nonamnestic MCI (na-MCI; 64.1±4.5 years) and 32 controls (63.7±6.6 years) participated in the study. Spectral analyses of the waking EEG and REM sleep EEG were performed and the [(delta+theta)/(alpha+beta)] ratio was used to assess between-group differences in EEG slowing. The a-MCI subgroup showed EEG slowing in frontal lateral regions compared to both na-MCI and control groups. This EEG slowing was present in wakefulness (compared to controls) but was much more prominent in REM sleep. Moreover, the comparison between amnestic and nonamnestic subjects was found significant only for the REM sleep EEG. There was no difference in EEG power ratio between na-MCI and controls for any of the 7 cortical regions studied. These findings demonstrate the superiority of the REM sleep EEG in the discrimination between a-MCI and both na-MCI and control subjects. © EEG and Clinical Neuroscience Society (ECNS) 2015.

  9. Rapid eye movement sleep behavior disorder after bilateral subthalamic stimulation in Parkinson's disease.

    Science.gov (United States)

    Kim, Young Eun; Jeon, Beom S; Paek, Sun-Ha; Yun, Ji Young; Yang, Hui-Jun; Kim, Han-Joon; Ehm, Gwanhee; Kim, Hee Jin; Lee, Jee-Young; Kim, Ji-Young

    2015-02-01

    The effect of subthalamic nucleus (STN) deep brain stimulation (DBS) on rapid eye movement sleep behavior disorder (RBD) in Parkinson's disease (PD) is not well known. We evaluated the change in the incidence of probable RBD after bilateral STN DBS in PD patients. Ninety patients with PD treated with bilateral STN DBS underwent retrospective assessment of RBD by interview before and after DBS. Forty-seven (52.2%) of the 90 patients had RBD preoperatively. RBD was resolved only in one patient and persisted in 46 patients at 1 year after DBS. RBD developed de novo in 16 patients (de novo RBD group) within 1 year after DBS, resulting in 62 (68.9%) of the 90 patients having RBD 1 year after DBS. Patients with RBD at any time within 1 year after DBS (RBD group, n = 63) were older than the patients without RBD (non-RBD group, n = 27). The sum of the Unified Parkinson Disease Rating Scale (UPDRS) axial score for the "on" state was lower in the RBD group than in the non-RBD group after DBS (p = 0.029). Comparing the de novo RBD group and non-RBD group, the UPDRS Part III and total score and the levodopa equivalent daily doses for the "on" states decreased more in the de novo RBD group than in the non-RBD group (p < 0.05). The incidence of clinical RBD increased after bilateral STN DBS because de novo RBD developed and pre-existing RBD persisted after DBS. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Apnea-induced rapid eye movement sleep disruption impairs human spatial navigational memory.

    Science.gov (United States)

    Varga, Andrew W; Kishi, Akifumi; Mantua, Janna; Lim, Jason; Koushyk, Viachaslau; Leibert, David P; Osorio, Ricardo S; Rapoport, David M; Ayappa, Indu

    2014-10-29

    Hippocampal electrophysiology and behavioral evidence support a role for sleep in spatial navigational memory, but the role of particular sleep stages is less clear. Although rodent models suggest the importance of rapid eye movement (REM) sleep in spatial navigational memory, a similar role for REM sleep has never been examined in humans. We recruited subjects with severe obstructive sleep apnea (OSA) who were well treated and adherent with continuous positive airway pressure (CPAP). Restricting CPAP withdrawal to REM through real-time monitoring of the polysomnogram provides a novel way of addressing the role of REM sleep in spatial navigational memory with a physiologically relevant stimulus. Individuals spent two different nights in the laboratory, during which subjects performed timed trials before and after sleep on one of two unique 3D spatial mazes. One night of sleep was normally consolidated with use of therapeutic CPAP throughout, whereas on the other night, CPAP was reduced only in REM sleep, allowing REM OSA to recur. REM disruption via this method caused REM sleep reduction and significantly fragmented any remaining REM sleep without affecting total sleep time, sleep efficiency, or slow-wave sleep. We observed improvements in maze performance after a night of normal sleep that were significantly attenuated after a night of REM disruption without changes in psychomotor vigilance. Furthermore, the improvement in maze completion time significantly positively correlated with the mean REM run duration across both sleep conditions. In conclusion, we demonstrate a novel role for REM sleep in human memory formation and highlight a significant cognitive consequence of OSA. Copyright © 2014 the authors 0270-6474/14/3414571-07$15.00/0.

  11. Rapid-Eye-Movement-Sleep (REM Associated Enhancement of Working Memory Performance after a Daytime Nap.

    Directory of Open Access Journals (Sweden)

    Esther Yuet Ying Lau

    Full Text Available The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40 or stay awake (Wake-group, n=40 between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM and total sleep time during the nap. Our findings suggested that "sleep gain" during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression, which are also presented with cognitive dysfunctions (e.g. working memory deficits, this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy.

  12. Rapid eye movement sleep in relation to overweight in children and adolescents.

    Science.gov (United States)

    Liu, Xianchen; Forbes, Erika E; Ryan, Neal D; Rofey, Dana; Hannon, Tamara S; Dahl, Ronald E

    2008-08-01

    Short sleep duration is associated with obesity, but few studies have examined the relationship between obesity and specific physiological stages of sleep. To examine specific sleep stages, including rapid eye movement (REM) sleep and stages 1 through 4 of non-REM sleep, in relation to overweight in children and adolescents. A total of 335 children and adolescents (55.2% male; aged 7-17 years) underwent 3 consecutive nights of standard polysomnography and weight and height assessments as part of a study on the development of internalizing disorders (depression and anxiety). Body mass index (calculated as weight in kilograms divided by height in meters squared) z score and weight status (normal, at risk for overweight, overweight) according to the body mass index percentile for age and sex. The body mass index z score was significantly related to total sleep time (beta = -0.174), sleep efficiency (beta = -0.027), and REM density (beta = -0.256). Compared with normal-weight children, overweight children slept about 22 minutes less and had lower sleep efficiency, shorter REM sleep, lower REM activity and density, and longer latency to the first REM period. After adjustment for demographics, pubertal status, and psychiatric diagnosis, 1 hour less of total sleep was associated with approximately 2-fold increased odds of overweight (odds ratio = 1.85), 1 hour less of REM sleep was associated with about 3-fold increased odds (odds ratio = 2.91), and REM density and activity below the median increased the odds of overweight by 2-fold (odds ratio = 2.18) and 3-fold (odds ratio = 3.32), respectively. Our results confirm previous epidemiological observations that short sleep time is associated with overweight in children and adolescents. A core aspect of the association between short sleep duration and overweight may be attributed to reduced REM sleep. Further studies are needed to investigate possible mechanisms underpinning the association between diminished REM sleep and

  13. Selective Rapid Eye Movement Sleep Deprivation Affects Cell Size and Number in Kitten Locus Coeruleus

    Directory of Open Access Journals (Sweden)

    James P Shaffery

    2012-05-01

    Full Text Available Cells in the locus coeruleus (LC constitute the sole source of norepinephrine (NE in the brain, and change their discharge rates according to vigilance state. In addition to its well established role in vigilance, NE affects synaptic plasticity in the postnatal critical period (CP of development. One form of CP synaptic plasticity affected by NE results from monocular occlusion, which leads to physiological and cytoarchitectural alterations in central visual areas. Selective suppression of rapid eye movement sleep (REMS in the CP kitten enhances the central effects of monocular occlusion. The mechanisms responsible for heightened cortical plasticity following REMS deprivation (REMSD remain undetermined. One possible mediator of an increase in plasticity is continuous NE outflow, which presumably persists during extended periods of REMSD. Tyrosine hydroxylase (TH is the rate-limiting enzyme in the synthesis of NE and serves as a marker for NE-producing cells. We selectively suppressed REMS in kittens for one week during the CP. The number and size of LC cells expressing immunoreactivity to tyrosine hydroxylase (TH-ir was assessed in age-matched REMS-deprived (RD-, treatment-control (TXC-, and home cage-reared (HCC animals. Sleep amounts and slow wave activity (SWA were also examined relative to baseline. Time spent in REMS during the study was lower in RD compared to TXC animals, and RD kittens increased SWA delta power in the latter half of the REMSD period. The estimated total number of TH-ir cells in LC was significantly lower in the RD- than in the TXC kittens and numerically lower than in HCC animals. The size of LC cells expressing TH-ir was greatest in the HCC group. They were significantly larger than the cells in the RD kittens. These data are consistent with a possible reduction in NE in forebrain areas, including visual cortex, caused by one week of REMSD.

  14. Rapid-Eye-Movement-Sleep (REM) Associated Enhancement of Working Memory Performance after a Daytime Nap.

    Science.gov (United States)

    Lau, Esther Yuet Ying; Wong, Mark Lawrence; Lau, Kristy Nga Ting; Hui, Florence Wai Ying; Tseng, Chia-huei

    2015-01-01

    The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males) were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40) or stay awake (Wake-group, n=40) between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM) and total sleep time during the nap. Our findings suggested that "sleep gain" during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression), which are also presented with cognitive dysfunctions (e.g. working memory deficits), this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy.

  15. Rapid Eye Movement Sleep Behavior Disorder: A Window on the Emotional World of Parkinson Disease

    Science.gov (United States)

    Mariotti, Paolo; Quaranta, Davide; Di Giacopo, Raffaella; Bentivoglio, Anna Rita; Mazza, Marianna; Martini, Annalisa; Canestri, Jorge; Della Marca, Giacomo

    2015-01-01

    Study Objectives: REM sleep behavior disorder (RBD) is a parasomnia characterized by motor activity during sleep with dream mentation. Aggressiveness has been considered a peculiar feature of dreams associated with RBD, despite normal score in aggressiveness scales during wakefulness. We aimed to measure daytime aggressiveness and analyze dream contents in a population of patients with Parkinson disease (PD) with and without RBD. Design: This is a single-center prospective observational study; it concerns the description of the clinical features of a medical disorder in a case series. Setting: The study was performed in the Department of Neurosciences of the Catholic University in Rome, Italy. Patients: Three groups of subjects were enrolled: patients with PD plus RBD, patients with PD without RBD, and healthy controls. Interventions: The diagnosis of RBD was determined clinically and confirmed by means of overnight, laboratory-based video-polysomnography. For the evaluation of diurnal aggressiveness, the Buss-Perry Aggression Questionnaire (BPAQ) was used. The content of dreams was evaluated by means of the methods of Hall and Van De Castle. Measurements and Results: Patients with PD without RBD displayed higher levels of anger, and verbal and physical aggressiveness than patients with PD and RBD and controls. Patients with PD and RBD and controls did not differ in hostility. Conclusions: It can be hypothesized that a noradrenergic impairment at the level of the locus coeruleus could, at the same time, explain the presence of REM sleep behavior disorder, as well as the reduction of diurnal aggressiveness. This finding also suggests a role for REM sleep in regulating homeostasis of emotional brain function. Citation: Mariotti P, Quaranta D, Di Giacopo R, Bentivoglio AR, Mazza M, Martini A, Canestri J, Della Marca G. Rapid eye movement sleep behavior disorder: a window on the emotional world of Parkinson disease. SLEEP 2015;38(2):287–294. PMID:25325501

  16. Validation of an integrated software for the detection of rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Frauscher, Birgit; Gabelia, David; Biermayr, Marlene; Stefani, Ambra; Hackner, Heinz; Mitterling, Thomas; Poewe, Werner; Högl, Birgit

    2014-10-01

    Rapid eye movement sleep without atonia (RWA) is the polysomnographic hallmark of REM sleep behavior disorder (RBD). To partially overcome the disadvantages of manual RWA scoring, which is time consuming but essential for the accurate diagnosis of RBD, we aimed to validate software specifically developed and integrated with polysomnography for RWA detection against the gold standard of manual RWA quantification. Academic referral center sleep laboratory. Polysomnographic recordings of 20 patients with RBD and 60 healthy volunteers were analyzed. N/A. Motor activity during REM sleep was quantified manually and computer assisted (with and without artifact detection) according to Sleep Innsbruck Barcelona (SINBAR) criteria for the mentalis ("any," phasic, tonic electromyographic [EMG] activity) and the flexor digitorum superficialis (FDS) muscle (phasic EMG activity). Computer-derived indices (with and without artifact correction) for "any," phasic, tonic mentalis EMG activity, phasic FDS EMG activity, and the SINBAR index ("any" mentalis + phasic FDS) correlated well with the manually derived indices (all Spearman rhos 0.66-0.98). In contrast with computerized scoring alone, computerized scoring plus manual artifact correction (median duration 5.4 min) led to a significant reduction of false positives for "any" mentalis (40%), phasic mentalis (40.6%), and the SINBAR index (41.2%). Quantification of tonic mentalis and phasic FDS EMG activity was not influenced by artifact correction. The computer algorithm used here appears to be a promising tool for REM sleep behavior disorder detection in both research and clinical routine. A short check for plausibility of automatic detection should be a basic prerequisite for this and all other available computer algorithms. © 2014 Associated Professional Sleep Societies, LLC.

  17. Study on transcranial sonography in patients with idiopathic rapid eye movement sleep behavior disorder

    Directory of Open Access Journals (Sweden)

    Xu-dong LI

    2016-04-01

    Full Text Available Objective To investigate the changes of transcranial sonography (TCS in patients with rapid eye movement sleep behavior disorder (RBD.  Methods Fifteen patients fulfilled the diagnostic criteria of RBD according to International Classification of Sleep Disorders (ICSD, 2nd edition. Under the monitor of polysomnography (PSG, the sleep architectures of all RBD cases were evaluated by Polysmith software and visual analysis. Furthermore, all RBD patients and 15 normal controls underwent TCS. Cases with substantia nigra echo intensity over Ⅲ grade and substantia nigra area over 0.20 cm2 were supposed to be hyperechogenicity. Additionally, the width of the third ventricle was measured and whether there was hyperechogenicity in basal ganglia was evaluated. The cognitive functions were evaluated by Mini-Mental State Examination (MMSE and Montreal Cognitive Assessment (MoCA.  Results RBD patients presented typical clinical manifestations and electrophysiologic changes. No significant difference (P = 0.080, 0.109 was found in the comparison of hyperechogenicity rate on substantia nigra (6/15 and basal ganglia (7/15 in RBD patients and normal controls (1/15, 2/15. No significant difference in the comparison of MoCA was found in RBD patients with or without substantia nigra hyperechogenicity (P = 0.075. The RBD patients with hyperechogenicity on basal ganglia had higher MMSE scores than those without hyperechogenicity on basal ganglia, and the difference was significant (P = 0.021.  Conclusions RBD which is suggested as the prodromal period of synucleinopathy may present hyperechogenicity in substantia nigra and basal ganglia on TCS. TCS could detect subclinical changes of brain and evaluate the risk of synucleinopathy. DOI: 10.3969/j.issn.1672-6731.2016.04.010

  18. Consolidation of strictly episodic memories mainly requires rapid eye movement sleep.

    Science.gov (United States)

    Rauchs, Géraldine; Bertran, Françoise; Guillery-Girard, Bérengère; Desgranges, Béatrice; Kerrouche, Nacer; Denise, Pierre; Foret, Jean; Eustache, Francis

    2004-05-01

    The aim of this study is to examine the effects of sleep deprivation during the first or second half of the night on episodic memory consolidation. Episodic memory is defined as memory for events located in time and space. It is also characterized by autonoetic consciousness, which gives a subject the conscious sensation of traveling back in time to relive the original event and forward into the future. Consolidation of episodic information was tested after 4-hour retention intervals, which followed learning and occurred during either the early or late half night, respectively dominated by slow wave sleep (SWS) or rapid eye movement (REM) sleep, or corresponding periods of wakefulness. Data collection occurred in the sleep laboratory. Forty-three young healthy subjects: 9 men and 34 women, age ranging from 18 to 26 years (mean 20.18 +/- 1.94 years) were included in this study. Waking after a 4-hour retention interval filled with early or late sleep, or 4-hour sleep deprivation, during early or late period of night. The cognitive task, named the What-Where-When test, was specially designed to assess factual, spatial, and temporal components of episodic memory. This task was associated with the Remember/Know paradigm to assess autonoetic consciousness. We measured performance on immediate free recall, delayed free recall (after a 4-hour interval of wakefulness or sleep), and delayed recognition. We also calculated a forgetting rate for each feature (factual, spatial, and temporal) and, for the recognition task, scores of autonoetic consciousness (R responses). REM-sleep deprivation was associated with significantly lower recall of spatial information compared to SWS deprivation (P sleep (P sleep deprivation was also associated with a higher forgetting rate of temporal information as compared to the early sleep condition (Psleep deprivation led subjects to give significantly fewer R responses, indicative of true memories, as compared to SWS deprivation (P sleep.

  19. Evaluation of the effects of the Arm Light Exoskeleton on movement execution and muscle activities: a pilot study on healthy subjects.

    Science.gov (United States)

    Pirondini, Elvira; Coscia, Martina; Marcheschi, Simone; Roas, Gianluca; Salsedo, Fabio; Frisoli, Antonio; Bergamasco, Massimo; Micera, Silvestro

    2016-01-23

    Exoskeletons for lower and upper extremities have been introduced in neurorehabilitation because they can guide the patient's limb following its anatomy, covering many degrees of freedom and most of its natural workspace, and allowing the control of the articular joints. The aims of this study were to evaluate the possible use of a novel exoskeleton, the Arm Light Exoskeleton (ALEx), for robot-aided neurorehabilitation and to investigate the effects of some rehabilitative strategies adopted in robot-assisted training. We studied movement execution and muscle activities of 16 upper limb muscles in six healthy subjects, focusing on end-effector and joint kinematics, muscle synergies, and spinal maps. The subjects performed three dimensional point-to-point reaching movements, without and with the exoskeleton in different assistive modalities and control strategies. The results showed that ALEx supported the upper limb in all modalities and control strategies: it reduced the muscular activity of the shoulder's abductors and it increased the activity of the elbow flexors. The different assistive modalities favored kinematics and muscle coordination similar to natural movements, but the muscle activity during the movements assisted by the exoskeleton was reduced with respect to the movements actively performed by the subjects. Moreover, natural trajectories recorded from the movements actively performed by the subjects seemed to promote an activity of muscles and spinal circuitries more similar to the natural one. The preliminary analysis on healthy subjects supported the use of ALEx for post-stroke upper limb robotic assisted rehabilitation, and it provided clues on the effects of different rehabilitative strategies on movement and muscle coordination.

  20. The Atomic Papers: A citizen's guide to selected books and articles on the bomb, the arms race, nuclear power, the peace movement, and related issues

    Energy Technology Data Exchange (ETDEWEB)

    Burns, G.

    1984-01-01

    The Atomic Papers annotates over 800 books published since 1945 and approximately 300 periodical articles since 1980 on every facet of the nuclear dilemma: the development and effects of the bomb, the arms race, nuclear proliferation, and the peace movement. Work on both sides of the nuclear power controversy also receives substantial attention. All references are to English-language material, and nearly half are to work published since 1980. The concluding chapter, ''The Art of Fission,'' describes over one hundred novels and stories with nuclear themes published since 1945--and, in a few cases, before that date.

  1. Neural control of arm movements reveals a tendency to use gravity to simplify joint coordination rather than to decrease muscle effort.

    Science.gov (United States)

    Wang, Wanyue; Dounskaia, Natalia

    2016-12-17

    How gravity influences neural control of arm movements remains under debate. We tested three alternative interpretations suggested by previous research: (1) that muscular control includes two components, tonic which compensates for gravity and phasic which produces the movement; (2) that there is a tendency to exploit gravity to reduce muscle effort; and (3) that there is a tendency to use a trailing pattern of joint control during which either the shoulder or elbow is rotated actively and the other joint rotates predominantly passively, and to exploit gravity for control of the passively rotated joint. A free-stroke drawing task was performed that required production of center-out strokes within a circle while selecting stroke directions randomly. The circle was positioned in the horizontal, sagittal, and frontal plane. The arm joints freely rotated in space. In each plane, the distribution of the strokes across directions was non-uniform. Directional histograms were built and their peaks were used to identify preferred movement directions. The directional preferences were especially pronounced in the two vertical planes. The upward directions were most preferred. To test the three interpretations, we used a kinetic analysis that determined the role of gravitational torque in the production of movement in the preferred directions. The results supported the third interpretation and provided evidence against the first and second interpretation. The trailing pattern has been associated with reduced neural effort for joint coordination, and therefore, we conclude that the major tendency with respect to gravity is to exploit it for simplification of joint coordination. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. The coordination of shoulder girdle muscles during repetitive arm movements at either slow or fast pace among women with or without neck-shoulder pain.

    Science.gov (United States)

    Januario, Leticia Bergamin; Oliveira, Ana Beatriz; Cid, Marina Machado; Madeleine, Pascal; Samani, Afshin

    2017-10-01

    The aim of this study was to evaluate the coordination of the shoulder girdle muscles among subjects with or without neck-shoulder pain performing repetitive arm movement at either a slow or fast pace. Thirty female adults were allocated to one of two groups-healthy controls or cases with neck-shoulder pain. Surface electromyography (sEMG) signals from the clavicular, acromial, middle and lower trapezius portions and the serratus anterior muscles were recorded during a task performed for 20min at a slow pace and 20min at a fast pace. The root mean square (RMS), relative rest time (RRT) and normalised mutual information (NMI, an index of functional connectivity between two muscles in a pair) were computed. No significant differences on RMS, RRT and NMI were found between groups. For both groups, the fast movement pace resulted in increased levels of RMS, lower degrees of RRT and higher NMI compared to the slow pace. No interaction between group and movement pace was found. This study highlights the change in sEMG activity of muscles to meet the demands of performing a task at fast movement pace. The fast pace imposed a higher muscle demand evidenced by increased sEMG amplitude, low degree of muscle rest and increased functional connectivity for subjects in both the case and control groups. No indication of impaired sEMG activity was found in individuals with neck-shoulder pain. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Influence of Gravity Compensation on Muscle Activation Patterns During Different Temporal Phases of Arm Movements of Stroke Patients

    NARCIS (Netherlands)

    Prange, Grada Berendina; Jannink, M.J.A.; Stienen, Arno; van der Kooij, Herman; IJzerman, Maarten Joost; Hermens, Hermanus J.

    2009-01-01

    Background. Arm support to help compensate for the effects of gravity may improve functional use of the shoulder and elbow during therapy after stroke, but gravity compensation may alter motor control. Objective. To obtain quantitative information on how gravity compensation influences muscle

  4. Motor imagery, P300 and error-related EEG-based robot arm movement control for rehabilitation purpose.

    Science.gov (United States)

    Bhattacharyya, Saugat; Konar, Amit; Tibarewala, D N

    2014-12-01

    The paper proposes a novel approach toward EEG-driven position control of a robot arm by utilizing motor imagery, P300 and error-related potentials (ErRP) to align the robot arm with desired target position. In the proposed scheme, the users generate motor imagery signals to control the motion of the robot arm. The P300 waveforms are detected when the user intends to stop the motion of the robot on reaching the goal position. The error potentials are employed as feedback response by the user. On detection of error the control system performs the necessary corrections on the robot arm. Here, an AdaBoost-Support Vector Machine (SVM) classifier is used to decode the 4-class motor imagery and an SVM is used to decode the presence of P300 and ErRP waveforms. The average steady-state error, peak overshoot and settling time obtained for our proposed approach is 0.045, 2.8% and 44 s, respectively, and the average rate of reaching the target is 95%. The results obtained for the proposed control scheme make it suitable for designs of prosthetics in rehabilitative applications.

  5. Transfer from table to wheelchair in men and women with spinal cord injury: coordination of body movement and arm forces

    National Research Council Canada - National Science Library

    Forslund, E B; Granström, A; Richard, Levi; Westgren, N; Hirschfeld, H

    2007-01-01

    ...: To investigate how men and women with spinal cord injury (SCI) perform transfers from table to wheelchair with regard to timing and magnitude of force generation beneath the hands and associated body movements.METHODS...

  6. Movement of Sediment Associated With Lowered Reservoir Levels in the Rio La Venta Arm of the Presa Netzahualcoyotl, Chiapas, Mexico

    Science.gov (United States)

    Hilton, S.; de La Fuente, J.; Lisle, T. E.; Velasquez, J.; Allison, B.; Olson, B.; Quinones, R.

    2003-12-01

    A joint sedimentation study is currently underway at the Netzahualcoyotl reservoir in Chiapas, Mexico, involving the Comision Nacional de Areas Naturales Protegidas (CONANP) of the Secretaria de Medio Ambiente y Recursos Naturales and the USDA Forest Service. The reservoir is adjacent to the Reserva de la Biosfera, Selva El Ocote, administered by CONANP. Ongoing research is intended to provide watershed and reservoir managers with strategies to protect the resources of Rio La Venta canyon. The Rio La Venta arm of the reservoir is incised into karst terrain, with near-vertical limestone walls up to 300 meters high. The canyon is fed by two rivers, Rio La Selva and Rio Negro, and is surrounded by pristine tropical forest. The majority of the clastic sediment (predominantly sand and fine gravel) entering the reservoir originates in the headwaters of the two rivers which are underlain by weathered and dissected granitic terrain. Rapid sedimentation of the partially inundated canyon poses a threat to the aquatic ecosystem, as well as to recreational resources. Longitudinal and transverse profiles were surveyed in the inundated canyon in March of 2002 and repeated in April of 2003 when the reservoir level was 15 meters lower. The 2002 longitudinal profile shows an inflection from a slope of 0.0017 to one of 0.0075 at 7.2 km downstream of the mouth of Rio Negro. In 2003, the two slopes remained the same, but the bed lowered about 5 meters and the inflection point moved downstream about 2.3 km. We calculated that reservoir lowering in 2003 allowed the transport of 2.5 million cubic meters of sand further out into the reservoir. This volume is more than the average annual rate of filling up to the 2002 level since 1984 when sedimentation was not as advanced (De la Fuente et al., 2002), which was calculated disregarding loss of sediment to the main reservoir. Field observations at late dry season low flows in 2003 revealed active transport of sand and pebbles and formation

  7. The link between Parkinson's disease and rapid eye movement sleep behavior disorder with dream enactment: Possible implications for early rehabilitation.

    Science.gov (United States)

    Johnson, Brian P; Westlake, Kelly P

    2017-09-07

    The purpose of this paper is twofold. First, to inform readers of the link between the loss of motor inhibition during rapid eye movement (REM) sleep dreaming, diagnosed as REM sleep behavior disorder (RBD), and the future onset of neurodegenerative disorders, such as Parkinson's Disease and dementia with lewy bodies. It has been reported that motor disinhibition during rapid eye movement sleep often precedes onset of these disorders by years or even decades. Second, to consider that identification of RBD and the early involvement of rehabilitation and/or development of home exercise plans may aid in prolonging and even increasing function, independence, and quality of life should such neurodegenerative disorders develop later in life. Copyright © 2017. Published by Elsevier Inc.

  8. The Circadian Clock Gene Csnk1e Regulates Rapid Eye Movement Sleep Amount, and Nonrapid Eye Movement Sleep Architecture in Mice

    Science.gov (United States)

    Zhou, Lili; Bryant, Camron D.; Loudon, Andrew; Palmer, Abraham A.; Vitaterna, Martha Hotz; Turek, Fred W.

    2014-01-01

    Study Objectives: Efforts to identify the genetic basis of mammalian sleep have included quantitative trait locus (QTL) mapping and gene targeting of known core circadian clock genes. We combined three different genetic approaches to identify and test a positional candidate sleep gene — the circadian gene casein kinase 1 epsilon (Csnk1e), which is located in a QTL we identified for rapid eye movement (REM) sleep on chromosome 15. Measurements and Results: Using electroencephalographic (EEG) and electromyographic (EMG) recordings, baseline sleep was examined in a 12-h light:12-h dark (LD 12:12) cycle in mice of seven genotypes, including Csnk1etau/tau and Csnk1e-/- mutant mice, Csnk1eB6.D2 and Csnk1eD2.B6 congenic mice, and their respective wild-type littermate control mice. Additionally, Csnk1etau/tau and wild-type mice were examined in constant darkness (DD). Csnk1etau/tau mutant mice and both Csnk1eB6.D2 and Csnk1eD2.B6 congenic mice showed significantly higher proportion of sleep time spent in REM sleep during the dark period than wild-type controls — the original phenotype for which the QTL on chromosome 15 was identified. This phenotype persisted in Csnk1etau/tau mice while under free-running DD conditions. Other sleep phenotypes observed in Csnk1etau/tau mice and congenics included a decreased number of bouts of nonrapid eye movement (NREM) sleep and an increased average NREM sleep bout duration. Conclusions: These results demonstrate a role for Csnk1e in regulating not only the timing of sleep, but also the REM sleep amount and NREM sleep architecture, and support Csnk1e as a causal gene in the sleep QTL on chromosome 15. Citation: Zhou L; Bryant CD; Loudon A; Palmer AA; Vitaterna MH; Turek FW. The circadian clock gene Csnk1e regulates rapid eye movement sleep amount, and nonrapid eye movement sleep architecture in mice. SLEEP 2014;37(4):785-793. PMID:24744456

  9. Uncontrolled manifold analysis of arm joint angle variability during robotic teleoperation and freehand movement of surgeons and novices.

    Science.gov (United States)

    Nisky, Ilana; Hsieh, Michael H; Okamura, Allison M

    2014-12-01

    Teleoperated robot-assisted surgery (RAS) is used to perform a wide variety of minimally invasive procedures. However, current understanding of the effect of robotic manipulation on the motor coordination of surgeons is limited. Recent studies in human motor control suggest that we optimize hand movement stability and task performance while minimizing control effort and improving robustness to unpredicted disturbances. To achieve this, the variability of joint angles and muscle activations is structured to reduce task-relevant variability and increase task-irrelevant variability. In this study, we determine whether teleoperation of a da Vinci Si surgical system in a nonclinical task of simple planar movements changes this structure of variability in experienced surgeons and novices. To answer this question, we employ the UnControlled manifold analysis that partitions users' joint angle variability into task-irrelevant and task-relevant manifolds. We show that experienced surgeons coordinate their joint angles to stabilize hand movements more than novices, and that the effect of teleoperation depends on experience--experts increase teleoperated stabilization relative to freehand whereas novices decrease it. We suggest that examining users' exploitation of the task-irrelevant manifold for stabilization of hand movements may be applied to: (1) evaluation and optimization of teleoperator design and control parameters, and (2) skill assessment and optimization of training in RAS.

  10. Nocturnal Rapid Eye Movement Sleep Latency for Identifying Patients With Narcolepsy/Hypocretin Deficiency

    Science.gov (United States)

    Andlauer, Olivier; Moore, Hyatt; Jouhier, Laura; Drake, Christopher; Peppard, Paul E.; Han, Fang; Hong, Seung-Chul; Poli, Francesca; Plazzi, Giuseppe; O’Hara, Ruth; Haffen, Emmanuel; Roth, Thomas; Young, Terry; Mignot, Emmanuel

    2014-01-01

    IMPORTANCE Narcolepsy, a disorder associated with HLA-DQB1*06:02 and caused by hypocretin (orexin) deficiency, is diagnosed using the Multiple Sleep Latency Test (MSLT) following nocturnal polysomnography (NPSG). In many patients, a short rapid eye movement sleep latency (REML) during the NPSG is also observed but not used diagnostically. OBJECTIVE To determine diagnostic accuracy and clinical utility of nocturnal REML measures in narcolepsy/hypocretin deficiency. DESIGN, SETTING, AND PARTICIPANTS Observational study using receiver operating characteristic curves for NPSG REML and MSLT findings (sleep studies performed between May 1976 and September 2011 at university medical centers in the United States, China, Korea, and Europe) to determine optimal diagnostic cutoffs for narcolepsy/hypocretin deficiency compared with different samples: controls, patients with other sleep disorders, patients with other hypersomnias, and patients with narcolepsy with normal hypocretin levels. Increasingly stringent comparisons were made. In a first comparison, 516 age- and sex-matched patients with narcolepsy/hypocretin deficiency were selected from 1749 patients and compared with 516 controls. In a second comparison, 749 successive patients undergoing sleep evaluation for any sleep disorders (low pretest probability for narcolepsy) were compared within groups by final diagnosis of narcolepsy/hypocretin deficiency. In the third comparison, 254 patients with a high pretest probability of having narcolepsy were compared within group by their final diagnosis. Finally, 118 patients with narcolepsy/hypocretin deficiency were compared with 118 age- and sex-matched patients with a diagnosis of narcolepsy but with normal hypocretin levels. MAIN OUTCOME AND MEASURES Sensitivity and specificity of NPSG REML and MSLT as diagnostic tests for narcolepsy/hypocretin deficiency. This diagnosis was defined as narcolepsy associated with cataplexy plus HLA-DQB1*06:02 positivity (no cerebrospinal

  11. The effects of two different auditory stimuli on functional arm movement in persons with Parkinson's disease: a dual-task paradigm.

    Science.gov (United States)

    Ma, Hui-Ing; Hwang, Wen-Juh; Lin, Keh-Chung

    2009-03-01

    To examine, in a dual-task paradigm, the effect of auditory stimuli on people with Parkinson's disease. A counterbalanced repeated-measures design. A motor control laboratory in a university setting. Twenty individuals with Parkinson's disease. EXPERIMENTAL CONDITIONS: Each participant did two experiments (marching music experiment and weather forecast experiment). In each experiment, the participant performed an upper extremity functional task as the primary task and listened to an auditory stimulus (marching music or weather forecast) as the concurrent task. Each experiment had three conditions: listening to the auditory stimulus, ignoring the auditory stimulus and no auditory stimulus. Kinematic variables of arm movement, including movement time, peak velocity, deceleration time and number of movement units. We found that performances of the participants were similar across the three conditions for the marching music experiment, but were significantly different for the weather forecast experiment. The comparison of condition effects between the two experiments indicated that the effect of weather forecast was (marginally) significantly greater than that of marching music. The results suggest that the type of auditory stimulus is important to the degree of interference with upper extremity performance in people with Parkinson's disease. Auditory stimuli that require semantic processing (e.g. weather forecast) may distract attention from the primary task, and thus cause a decline in performance.

  12. Dealing with the Empty Vehicle Movements in Personal Rapid Transit System with Batteries Constraints in a Dynamic Context

    Directory of Open Access Journals (Sweden)

    Ezzeddine Fatnassi

    2017-01-01

    Full Text Available The Personal Rapid Transit is a new emergent transportation tool. It relies on using a set of small driverless electric vehicles to transport people on demand. Because of the specific on-demand characteristic of the Personal Rapid Transit system, many Personal Rapid Transit vehicles would move empty which results in a high level of wasted transportation capacity. This is enhanced while using Personal Rapid Transit vehicles with limited electric battery capacity. This paper deals with this problem in a real time context while minimizing the set of empty vehicle movements. First, a mathematical formulation to benchmark waiting time of passengers in Personal Rapid Transit systems is proposed. Then, a simulation model that captures the main features of the Personal Rapid Transit system is developed. A decision support system which integrates several real time solution strategies as well as a simulation module is proposed. Our dispatching strategies are evaluated and compared based on our simulation model. The efficiency of our method is tested through extensive test studies.

  13. Impact forces cannot explain the one-target advantage in rapid aimed hand movements

    NARCIS (Netherlands)

    Biegstraaten, Marianne; Smeets, Jeroen B J; Brenner, Eli

    A pointing movement is executed faster when a subject is allowed to stop at the first target than when the subject has to proceed to a second target ("one-target advantage"). Our hypothesis was that this is because the impact at the target helps to stop the finger when the finger does not have to

  14. Brain-Machine Interface to Control a Prosthetic Arm with Monkey ECoGs during Periodic Movements

    Directory of Open Access Journals (Sweden)

    Soichiro eMorishita

    2014-12-01

    Full Text Available Brain Machine Interfaces (BMIs are promising technologies to rehabilitate the function of upper limbs in severely paralyzed patients. We succeeded in developing a BMI prosthetic arm for a monkey implanted with electrocorticogram (ECoG electrodes and trained in a reaching task. It had stability in preventing the misclassification of ECoG patterns. However, the latency was about 200 ms as a trade-off for the stability. To improve the response of this BMI prosthetic arm, the generation of a trigger event by decoding muscle activity was adopted. It was performed to predict integrated electromyograms (iEMGs from the ECoGs. Experiments were conducted to verify the availability of this method, and the results confirmed that the proposed method was superior to the conventional one. In addition, a performance test of the proposed method with actually achieved iEMGs instead of predicted iEMGs was performed, and we found that the motor intention is finely expressed through estimated muscle activity from brain activity rather than actual muscle activity.

  15. Effects of neck flexion on contingent negative variation and anticipatory postural control during arm movement while standing.

    Science.gov (United States)

    Fujiwara, Katsuo; Tomita, Hidehito; Maeda, Kaoru; Kunita, Kenji

    2009-02-01

    We investigated the effects of neck flexion on contingent negative variation (CNV) and anticipatory postural control using an arm flexion task in standing. CNV was adopted to evaluate the state of activation of brain areas related to anticipatory postural control. Subjects were required to flex the arms in response to a sound stimulus preceded by a warning sound stimulus. Two different intervals (2.0 and 3.5s) between these two stimuli were used in neck position in quiet standing (neck resting) and neck position at 80% angle of maximal neck flexion. The mean amplitude of CNV 100-ms before the response stimulus, recorded from a Cz electrode, was calculated. Onset timing of activation of the postural muscles (lumbar paraspinal, biceps femoris and gastrocnemius) with respect to the anterior deltoid was analyzed. Reaction time at the anterior deltoid was significantly shorter in the 2.0s period than in the 3.5s period, and in the neck flexion than in the neck resting in both periods. In the 2.0s, but not in the 3.5s period, neck flexion resulted in an increased CNV amplitude and an increased duration of preceding activation of the postural muscles, and the correlation between these increases was significant.

  16. Correlation between regular mouthing movements and heart rate patterns during non-rapid eye movement periods in normal human fetuses between 32 and 40 weeks of gestation.

    Science.gov (United States)

    Otera, Yuka; Morokuma, Seiichi; Fukushima, Kotaro; Wake, Norio; Kato, Kiyoko

    2013-06-01

    Regular mouthing movements (RMMs) are observed during fetal non-rapid eye movement (NREM) periods. To determine the correlation between RMM and fetal heart rate (FHR) patterns during NREM periods. Fetal eye and mouth movements and FHR patterns were observed and recorded. 50 normal singleton pregnancies between 32 and 40 weeks of gestation. Changes in the power spectrum ratio of 3-minute blocks of RMM clusters, FHR with RMM clusters (HR+), and FHR without RMM clusters (HR-) were calculated at a frequency band of 0.02 Hz among 3 gestational age groups: group 1, 32-34 weeks gestation; group 2, 35-37 weeks gestation; group 3, 38-40 weeks gestation. We calculated the percentage of cases showing dominant peak ratios of RMM and HR+ in the same frequency band, the maximum correlation coefficient, and its lag time. In group 3, the dominant peaks of both RM and HR+ were present at the same frequency band, 0.06-0.08 Hz; this was not seen in the other groups' relative power spectral patterns. The percentage of cases showing dominant peaks of RMM and HR+ in the same frequency band increased with advancing gestational age. The maximum correlation coefficient in groups 1 (0.28 ± 0.11) and 3 (0.45 ± 0.14) differed significantly (p<0.05). The correlation between RMM and FHR patterns became stronger, and their rhythmicity was similar, from 38 to 40 gestational weeks, suggesting that a common center starts to govern both patterns at approximately 38 weeks gestation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Study on the relation of brain functional connectivity to movement disorders and cognitive impairment in patients with rapid eye movement sleep behavior disorder

    Directory of Open Access Journals (Sweden)

    Hong-ju ZHANG

    2017-09-01

    Full Text Available Objective To explore the relation between abnormal functional connectivity of substantia nigra and impairment of movement and cognition in patients with rapid eye movement sleep behavior disorder (RBD. Methods A total of 22 subjects, including 14 patients with RBD and 8 sex, age, education-matched healthy controls, were enrolled in this study according to international diagnostic criteria. Unified Parkinson's Disease Rating Scale Ⅲ (UPDRS Ⅲ and Hoehn-Yahr Stage were used to evaluate motor function. Digit Ordering Test - Attention (DOT - A, Symbol Digit Modalities Test (SDMT, Stroop Color-Word Test (SCWT, Trail Making Test (TMT, Rey-Osterrieth Complex Figure Test (ROCFT, Clock Drawing Test (CDT, Boston Naming Test (BNT and Auditory Verbal Learning Test (AVLT were used to evaluate cognitive function. The functional connectivity from left and right substantia nigra to brain region were examined. Results There were no statistical differences of UPDRSⅢ and Hoehn?Yahr Stage between 2 groups (P > 0.05, for all. In comparison with control group, SDMT (P = 0.001, ROCFT-copy (P = 0.013 and AVLT-N2 (P = 0.032 were significantly lower, while TMT-B test was significantly higher (P =0.005 in RBD group. Compared with control group, the functional connectivity of right substantia nigra to left precentral gyrus (P < 0.005 and right angular gyrus (P < 0.005 were all decreased in RBD group. Conclusions The results suggest that cognitive impairment occurs earlier than movement disorders in RBD, and there are abnormal functional connectivity from right substantia nigra to left precentral gyrus and right angular gyrus, proving that abnormal functional connectivity is the base of behavior disorders in RBD. DOI: 10.3969/j.issn.1672-6731.2017.09.005

  18. [Assessment of the risk of arm repetitive movements among workers in the motor vehicle glass finishing industry].

    Science.gov (United States)

    Corrao, C R N; Talarico, G; Varone, A

    2007-01-01

    The aim of the study was to evaluate risk associated with biomechanical overload of the upper limbs in workers exposed to repetitive movements, employed to the finishing of glasses for motor vehicles. The risk assessment was performed using the OCRA method (OCRA index for every worker and Check-List OCRA for every workstation) and the results have been distributed for exposure levels. Altogether the results suggested the existence of risk associated with repetitive movements of the upper limbs and different risk classes (high, medium, light, very light). OCRA index and Check-List OCRA values showed together high risk in the workers with age and employment duration great (respectively 20.68% e 27.58% of workers), with especially involvement of the women, employed to jobs with high frequency.

  19. A rapid phenol toxicity test based on photosynthesis and movement of the freshwater flagellate, Euglena agilis Carter

    Energy Technology Data Exchange (ETDEWEB)

    Kottuparambil, Sreejith [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Kim, Youn-Jung [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Department of Marine Science, Incheon National University, Incheon 406 840 (Korea, Republic of); Green-Pioneer (Ltd.), Incheon National University, Incheon 406 840 (Korea, Republic of); Choi, Hoon; Kim, Mi-Sung; Park, Areum; Park, Jihae [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Shin, Woongghi [Department of Biology, Chungnam University, Daejeon 306 764 (Korea, Republic of); Han, Taejun, E-mail: hanalgae@hanmail.net [Institute of Green Environmental Research Center, Incheon National University, Incheon 406 840 (Korea, Republic of); Department of Marine Science, Incheon National University, Incheon 406 840 (Korea, Republic of); Green-Pioneer (Ltd.), Incheon National University, Incheon 406 840 (Korea, Republic of)

    2014-10-15

    Highlights: • Rapid phenol toxicity tests (1 h) were developed based on Chl a fluorescence and the movement parameters of Euglena agilis. • Phenol significantly reduced F{sub v}/F{sub m} of PS II and rETRmax with EC50 values of 8.94 and 4.67 mM, respectively. • Among the movement parameters tested, velocity was the most sensitive biomarker with an EC50 of 3.17 mM. • The EC50 values for F{sub v}/F{sub m}, motility, and velocity appear to overlap the environmental permissible levels of phenol. - Abstract: Phenol, a monosubstituted aromatic hydrocarbon with various commercial uses, is a major organic constituent in industrial wastewaters. The ecotoxic action of phenol for aquatic environment is well known. In this study, rapid phenol toxicity tests (1 h) were developed based on chlorophyll a (Chl a) fluorescence and the movement parameters of the freshwater flagellate, Euglena agilis Carter. Phenol significantly reduced the maximum quantum yield (F{sub v}/F{sub m}) of photosystem II (PS II) and the maximum photosynthetic electron transport rate (rETR{sub max}) with median effective concentration (EC{sub 50}) values of 8.94 and 4.67 mM, respectively. Phenol reduced the motility and triggered change in the swimming velocity of the test organism. Among the parameters tested, velocity was the most sensitive biomarker with an EC{sub 50} of 3.17 mM. The EC{sub 50} values for F{sub v}/F{sub m}, motility, and velocity appear to overlap the permitted levels of phenol. In conclusion, the photosynthesis and movement of E. agilis can be fast and sensitive risk assessment parameters for the evaluation of phenol toxicity in municipal and industrial effluents.

  20. Brain state-dependent robotic reaching movement with a multi-joint arm exoskeleton: combining brain-machine interfacing and robotic rehabilitation.

    Science.gov (United States)

    Brauchle, Daniel; Vukelić, Mathias; Bauer, Robert; Gharabaghi, Alireza

    2015-01-01

    While robot-assisted arm and hand training after stroke allows for intensive task-oriented practice, it has provided only limited additional benefit over dose-matched physiotherapy up to now. These rehabilitation devices are possibly too supportive during the exercises. Neurophysiological signals might be one way of avoiding slacking and providing robotic support only when the brain is particularly responsive to peripheral input. We tested the feasibility of three-dimensional robotic assistance for reaching movements with a multi-joint exoskeleton during motor imagery (MI)-related desynchronization of sensorimotor oscillations in the β-band. We also registered task-related network changes of cortical functional connectivity by electroencephalography via the imaginary part of the coherence function. Healthy subjects and stroke survivors showed similar patterns-but different aptitudes-of controlling the robotic movement. All participants in this pilot study with nine healthy subjects and two stroke patients achieved their maximum performance during the early stages of the task. Robotic control was significantly higher and less variable when proprioceptive feedback was provided in addition to visual feedback, i.e., when the orthosis was actually attached to the subject's arm during the task. A distributed cortical network of task-related coherent activity in the θ-band showed significant differences between healthy subjects and stroke patients as well as between early and late periods of the task. Brain-robot interfaces (BRIs) may successfully link three-dimensional robotic training to the participants' efforts and allow for task-oriented practice of activities of daily living with a physiologically controlled multi-joint exoskeleton. Changes of cortical physiology during the task might also help to make subject-specific adjustments of task difficulty and guide adjunct interventions to facilitate motor learning for functional restoration, a proposal that warrants

  1. Brain-state dependent robotic reaching movement with a multi-joint arm exoskeleton: combining brain-machine interfacing and robotic rehabilitation

    Directory of Open Access Journals (Sweden)

    Daniel eBrauchle

    2015-10-01

    Full Text Available While robot-assisted arm and hand training after stroke allows for intensive task-oriented practice, it has provided only limited additional benefit over dose-matched physiotherapy up to now. These rehabilitation devices are possibly too supportive during the exercises. Neurophysiological signals might be one way of avoiding slacking and providing robotic support only when the brain is particularly responsive to peripheral input.We tested the feasibility of three-dimensional robotic assistance for reach-to-grasp movements with a multi-joint exoskeleton during motor imagery-related desynchronization of sensorimotor oscillations in the β-band only. We also registered task-related network changes of cortical functional connectivity by electroencephalography via the imaginary part of the coherence function.Healthy subjects and stroke survivors showed similar patterns – but different aptitudes – of controlling the robotic movement. All participants in this pilot study with nine healthy subjects and two stroke patients achieved their maximum performance during the early stages of the task. Robotic control was significantly higher and less variable when proprioceptive feedback was provided in addition to visual feedback, i.e. when the orthosis was actually attached to the subject’s arm during the task. A distributed cortical network of task-related coherent activity in the θ-band showed significant differences between healthy subjects and stroke patients as well as between early and late periods of the task.Brain-robot interfaces may successfully link three-dimensional robotic training to the participants’ efforts and allow for task-oriented practice of activities of daily living with a physiologically controlled multi-joint exoskeleton. Changes of cortical physiology during the task might also help to make subject-specific adjustments of task difficulty and guide adjunct interventions to facilitate motor learning for functional restoration.

  2. Effects of regular heel-raise training aimed at the soleus muscle on dynamic balance associated with arm movement in elderly women.

    Science.gov (United States)

    Fujiwara, Katsuo; Toyama, Hiroshi; Asai, Hitoshi; Yaguchi, Chie; Irei, Mariko; Naka, Masami; Kaida, Chizuru

    2011-09-01

    The effects of low-intensity muscle training with heel-raises on dynamic balance associated with bilateral arm flexion were investigated in postmenopausal elderly women. Twenty-six elderly women were evenly grouped into training and control groups. Training group subjects performed 100 heel raises per day for 2 months. The training was aimed at hypertrophy of the soleus muscle, which has a relatively high proportion (ca. 90%) of slow-twitch muscle fibers and is one of the main postural muscles. Dynamic balance was measured while arm flexion was performed in response to a visual stimulus (simple-reaction condition) or at the subjects' own pace (own-timing condition). The following parameters were compared before and after the training period: plantar flexion strength, thicknesses of the gastrocnemius and soleus (by ultrasound), reaction time of the anterior deltoid in the simple-reaction condition, activation onset timing of postural muscles with respect to the deltoid, movement angles of ankle and hip joints, and postural fluctuation. In the training group only, the following training-related effects were demonstrated: (a) increase in plantar flexor strength and thickness of the soleus, (b) shortening of the deltoid reaction time, (c) earlier activation of the erector spinae in the simple-reaction condition and the soleus in the own-timing condition, and (d) increase in ankle movement in the own-timing condition and a decrease in postural fluctuation. This heel-raise training in the elderly can increase soleus thickness within the triceps surae and improve postural control modality and stability that are effectively contributed to by the leg muscle. This training consists of a low-intensity exercise that requires neither special machines nor a specific environment and can be performed safely for all old-aged groups.

  3. Visual Working Memory Modulates Rapid Eye Movements to Simple Onset Targets

    OpenAIRE

    Hollingworth, Andrew; Matsukura, Michi; Luck, Steven J.

    2013-01-01

    Visual working memory (VWM) representations influence attention and gaze control in complex tasks, such as visual search, that require top-down selection to resolve stimulus competition. VWM and visual attention clearly interact, but the mechanism of that interaction is not well understood. Here we demonstrate that VWM representations of object features influence the spatiotemporal dynamics of extremely simple eye movements, in the absence of stimulus competition or goal-level biases. The rea...

  4. A crossover pilot study evaluating the functional outcomes of two different types of robotic movement training in chronic stroke survivors using the arm exoskeleton BONES.

    Science.gov (United States)

    Milot, Marie-Hélène; Spencer, Steven J; Chan, Vicky; Allington, James P; Klein, Julius; Chou, Cathy; Bobrow, James E; Cramer, Steven C; Reinkensmeyer, David J

    2013-12-19

    To date, the limited degrees of freedom (DOF) of most robotic training devices hinders them from providing functional training following stroke. We developed a 6-DOF exoskeleton ("BONES") that allows movement of the upper limb to assist in rehabilitation. The objectives of this pilot study were to evaluate the impact of training with BONES on function of the affected upper limb, and to assess whether multijoint functional robotic training would translate into greater gains in arm function than single joint robotic training also conducted with BONES. Twenty subjects with mild to moderate chronic stroke participated in this crossover study. Each subject experienced multijoint functional training and single joint training three sessions per week, for four weeks, with the order of presentation randomized. The primary outcome measure was the change in Box and Block Test (BBT). The secondary outcome measures were the changes in Fugl-Meyer Arm Motor Scale (FMA), Wolf Motor Function Test (WMFT), Motor Activity Log (MAL), and quantitative measures of strength and speed of reaching. These measures were assessed at baseline, after each training period, and at a 3-month follow-up evaluation session. Training with the robotic exoskeleton resulted in significant improvements in the BBT, FMA, WMFT, MAL, shoulder and elbow strength, and reaching speed (p robotic training programs. However, for the BBT, WMFT and MAL, inequality of carryover effects were noted; subsequent analysis on the change in score between the baseline and first period of training again revealed no difference in the gains obtained between the types of training. Training with the 6 DOF arm exoskeleton improved motor function after chronic stroke, challenging the idea that robotic therapy is only useful for impairment reduction. The pilot results presented here also suggest that multijoint functional robotic training is not decisively superior to single joint robotic training. This challenges the idea that

  5. Cerebral O2 metabolism and cerebral blood flow in humans during deep and rapid-eye-movement sleep

    DEFF Research Database (Denmark)

    Madsen, P L; Schmidt, J F; Wildschiødtz, Gordon

    1991-01-01

    It could be expected that the various stages of sleep were reflected in variation of the overall level of cerebral activity and thereby in the magnitude of cerebral metabolic rate of oxygen (CMRO2) and cerebral blood flow (CBF). The elusive nature of sleep imposes major methodological restrictions...... on examination of this question. We have now measured CBF and CMRO2 in young healthy volunteers using the Kety-Schmidt technique with 133Xe as the inert gas. Measurements were performed during wakefulness, deep sleep (stage 3/4), and rapid-eye-movement (REM) sleep as verified by standard polysomnography...

  6. Vasoactive intestinal polypeptide excites medial pontine reticular formation neurons in the brainstem rapid eye movement sleep-induction zone

    DEFF Research Database (Denmark)

    Kohlmeier, Kristi Anne; Reiner, P B

    1999-01-01

    Although it has long been known that microinjection of the cholinergic agonist carbachol into the medial pontine reticular formation (mPRF) induces a state that resembles rapid eye movement (REM) sleep, it is likely that other transmitters contribute to mPRF regulation of behavioral states. A key...... conclude that VIP excites mPRF neurons by activation of a sodium current. This effect is mediated at least in part by G-protein stimulation of adenylyl cyclase, cAMP, and protein kinase A. These data suggest that VIP may play a physiological role in REM induction by its actions on mPRF neurons....

  7. Normal Morning Melanin-Concentrating Hormone Levels and No Association with Rapid Eye Movement or Non-Rapid Eye Movement Sleep Parameters in Narcolepsy Type 1 and Type 2.

    Science.gov (United States)

    Schrölkamp, Maren; Jennum, Poul J; Gammeltoft, Steen; Holm, Anja; Kornum, Birgitte R; Knudsen, Stine

    2017-02-15

    Other than hypocretin-1 (HCRT-1) deficiency in narcolepsy type 1 (NT1), the neurochemical imbalance of NT1 and narcolepsy type 2 (NT2) with normal HCRT-1 levels is largely unknown. The neuropeptide melanin-concentrating hormone (MCH) is mainly secreted during sleep and is involved in rapid eye movement (REM) and non-rapid eye movement (NREM) sleep regulation. Hypocretin neurons reciprocally interact with MCH neurons. We hypothesized that altered MCH secretion contributes to the symptoms and sleep abnormalities of narcolepsy and that this is reflected in morning cerebrospinal fluid (CSF) MCH levels, in contrast to previously reported normal evening/afternoon levels. Lumbar CSF and plasma were collected from 07:00 to 10:00 from 57 patients with narcolepsy (subtypes: 47 NT1; 10 NT2) diagnosed according to International Classification of Sleep Disorders, Third Edition (ICSD-3) and 20 healthy controls. HCRT-1 and MCH levels were quantified by radioimmunoassay and correlated with clinical symptoms, polysomnography (PSG), and Multiple Sleep Latency Test (MSLT) parameters. CSF and plasma MCH levels were not significantly different between narcolepsy patients regardless of ICSD-3 subtype, HCRT-1 levels, or compared to controls. CSF MCH and HCRT-1 levels were not significantly correlated. Multivariate regression models of CSF MCH levels, age, sex, and body mass index predicting clinical, PSG, and MSLT parameters did not reveal any significant associations to CSF MCH levels. Our study shows that MCH levels in CSF collected in the morning are normal in narcolepsy and not associated with the clinical symptoms, REM sleep abnormalities, nor number of muscle movements during REM or NREM sleep of the patients. We conclude that morning lumbar CSF MCH measurement is not an informative diagnostic marker for narcolepsy.

  8. Visual working memory modulates rapid eye movements to simple onset targets.

    Science.gov (United States)

    Hollingworth, Andrew; Matsukura, Michi; Luck, Steven J

    2013-05-01

    Representations in visual working memory (VWM) influence attention and gaze control in complex tasks, such as visual search, that require top-down selection to resolve stimulus competition. VWM and visual attention clearly interact, but the mechanism of that interaction is not well understood. In the research reported here, we demonstrated that in the absence of stimulus competition or goal-level biases, VWM representations of object features influence the spatiotemporal dynamics of extremely simple eye movements. The influence of VWM therefore extends into the most basic operations of the oculomotor system.

  9. An exploratory investigation on the use of closed-loop electrical stimulation to assist individuals with stroke to perform fine movements with their hemiparetic arm

    Directory of Open Access Journals (Sweden)

    Brian eLew

    2016-03-01

    Full Text Available Stroke is the leading cause of upper limb impairments resulting in disability. Modern rehabilitation includes training with robotic exoskeletons and functional electrical stimulation (FES. However, there is a gap in knowledge to define the detailed use of FES in stroke rehabilitation. In this paper, we explore applying closed-loop FES to the upper extremities (UE of healthy volunteers and individuals with a hemiparetic arm resulting from stroke. We used a set of gyroscopes to monitor arm movements and used a non-linear controller, namely the robust integral of the sign of the error (RISE, to assess the viability of controlling FES in closed-loop. Further, we explored the application of closed-loop FES in improving functional tasks performed by individuals with stroke. Four healthy individuals of ages 27 to 32 years old and five individuals with stroke of ages 61 to 83 years old participated in this study. We used the Rehastim FES unit (Hasomed Ltd. with real-time modulation of pulse width and amplitude. Both healthy and stroke individuals were tested in RISE controlled single and multi-joint upper limb motions following first a sinusoidal trajectory. Individuals with stroke were also asked to perform the following functional tasks: picking up a basket, picking and placing an object on a table, cutting a pizza, pulling back a chair, eating with a spoon, as well as using a stapler and grasping a pen. Healthy individuals were instructed to keep their arm relaxed during the experiment. Most individuals with stroke were able to follow the sinusoid trajectories with their arm joints under the sole excitation of the closed-loop controlled FES. One individual with stroke who was unable to perform any of the functional tasks independently, succeeded in completing all the tasks when FES was used. Three other individuals with stroke, who were unable to complete a few tasks independently, completed some of them when FES was used. The remaining stroke

  10. Just a scary dream? A brief review of sleep terrors, nightmares, and rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Haupt, Mark; Sheldon, Stephen H; Loghmanee, Darius

    2013-10-01

    The clinical spectrum of sleep disorders in children is broad, ranging from primary snoring and obstructive sleep apnea (OSA) syndrome to complex sleep-related behaviors and movement disorders. Although snoring and OSA typically receive significant attention and discussion, other biologically based sleep disorders are as common, if not more common, in children. A general pediatrician is frequently presented with the complaint of sleep talking, sleep walking, or abnormal movements during sleep. Even more alarming is the presentation of the child suddenly and explosively screaming during sleep. Such complaints fall under the category of parasomnias. Exclusive to sleep and wake-to-sleep transitions, these parasomnias include arousals with abnormal motor, behavioral, autonomic, or sensory symptoms. Parasomnias can be noticeably dissimilar in clinical manifestations, but most share biologic characteristics. Three parasomnias associated with loud vocalizations associated with sleep that can present to general practitioners include sleep terrors, nightmares, and rapid eye movement sleep behavior disorder (RBD). Although usually benign, these sleep disorders can be disruptive and even potentially dangerous to the patient and can often be threatening to quality of life. In this article, we describe the clinical features of some of these disorders and how to differentiate between their alarming presentations. Copyright 2013, SLACK Incorporated.

  11. Shorter duration of non-rapid eye movement sleep slow waves in EphA4 knockout mice.

    Science.gov (United States)

    Freyburger, Marlène; Poirier, Gaétan; Carrier, Julie; Mongrain, Valérie

    2017-10-01

    Slow waves occurring during non-rapid eye movement sleep have been associated with neurobehavioural performance and memory. In addition, the duration of previous wakefulness and sleep impacts characteristics of these slow waves. However, molecular mechanisms regulating the dynamics of slow-wave characteristics remain poorly understood. The EphA4 receptor regulates glutamatergic transmission and synaptic plasticity, which have both been linked to sleep slow waves. To investigate if EphA4 regulates slow-wave characteristics during non-rapid eye movement sleep, we compared individual parameters of slow waves between EphA4 knockout mice and wild-type littermates under baseline conditions and after a 6-h sleep deprivation. We observed that, compared with wild-type mice, knockout mice display a shorter duration of positive and negative phases of slow waves under baseline conditions and after sleep deprivation. However, the mutation did not change slow-wave density, amplitude and slope, and did not affect the sleep deprivation-dependent changes in slow-wave characteristics, suggesting that EphA4 is not involved in the response to elevated sleep pressure. Our present findings suggest a role for EphA4 in shaping cortical oscillations during sleep that is independent from sleep need. © 2017 European Sleep Research Society.

  12. Fragmentation of Rapid Eye Movement and Nonrapid Eye Movement Sleep without Total Sleep Loss Impairs Hippocampus-Dependent Fear Memory Consolidation.

    Science.gov (United States)

    Lee, Michael L; Katsuyama, Ângela M; Duge, Leanne S; Sriram, Chaitra; Krushelnytskyy, Mykhaylo; Kim, Jeansok J; de la Iglesia, Horacio O

    2016-11-01

    Sleep is important for consolidation of hippocampus-dependent memories. It is hypothesized that the temporal sequence of nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep is critical for the weakening of nonadaptive memories and the subsequent transfer of memories temporarily stored in the hippocampus to more permanent memories in the neocortex. A great body of evidence supporting this hypothesis relies on behavioral, pharmacological, neural, and/or genetic manipulations that induce sleep deprivation or stage-specific sleep deprivation. We exploit an experimental model of circadian desynchrony in which intact animals are not deprived of any sleep stage but show fragmentation of REM and NREM sleep within nonfragmented sleep bouts. We test the hypothesis that the shortening of NREM and REM sleep durations post-training will impair memory consolidation irrespective of total sleep duration. When circadian-desynchronized animals are trained in a hippocampus-dependent contextual fear-conditioning task they show normal short-term memory but impaired long-term memory consolidation. This impairment in memory consolidation is positively associated with the post-training fragmentation of REM and NREM sleep but is not significantly associated with the fragmentation of total sleep or the total amount of delta activity. We also show that the sleep stage fragmentation resulting from circadian desynchrony has no effect on hippocampus-dependent spatial memory and no effect on hippocampus-independent cued fear-conditioning memory. Our findings in an intact animal model, in which sleep deprivation is not a confounding factor, support the hypothesis that the stereotypic sequence and duration of sleep stages play a specific role in long-term hippocampus-dependent fear memory consolidation.

  13. Fight or flight? Dream content during sleepwalking/sleep terrors vs. rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Uguccioni, Ginevra; Golmard, Jean-Louis; de Fontréaux, Alix Noël; Leu-Semenescu, Smaranda; Brion, Agnès; Arnulf, Isabelle

    2013-05-01

    Dreams enacted during sleepwalking or sleep terrors (SW/ST) may differ from those enacted during rapid eye movement sleep behavior disorder (RBD). Subjects completed aggression, depression, and anxiety questionnaires. The mentations associated with SW/ST and RBD behaviors were collected over their lifetime and on the morning after video polysomnography (PSG). The reports were analyzed for complexity, length, content, setting, bizarreness, and threat. Ninety-one percent of 32 subjects with SW/ST and 87.5% of 24 subjects with RBD remembered an enacted dream (121 dreams in a lifetime and 41 dreams recalled on the morning). These dreams were more complex and less bizarre, with a higher level of aggression in the RBD than in SW/ST subjects. In contrast, we found low aggression, anxiety, and depression scores during the daytime in both groups. As many as 70% of enacted dreams in SW/ST and 60% in RBD involved a threat, but there were more misfortunes and disasters in the SW/ST dreams and more human and animal aggressions in the RBD dreams. The response to these threats differed, as the sleepwalkers mostly fled from a disaster (and 25% fought back when attacked), while 75% of RBD subjects counterattacked when assaulted. The dreams setting included their bedrooms in 42% SW/ST dreams, though this finding was exceptional in the RBD dreams. Different threat simulations and modes of defense seem to play a role during dream-enacted behaviors (e.g., fleeing a disaster during SW/ST, counterattacking a human or animal assault during RBD), paralleling and exacerbating the differences observed between normal dreaming in nonrapid eye movement (NREM) vs rapid eye movement (REM) sleep. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Miniscrew-assisted rapid palatal expander (MARPE: the quest for pure orthopedic movement

    Directory of Open Access Journals (Sweden)

    Hideo Suzuki

    Full Text Available ABSTRACT The midpalatal suture has bone margins with thick connective tissue interposed between them, and it does not represent the fusion of maxillary palatal processes only, but also the fusion of palatal processes of the jaws and horizontal osseous laminae of palatal bones. Changing it implies affecting neighboring areas. It has got three segments that should be considered by all clinical analyses, whether therapeutic or experimental: the anterior segment (before the incisive foramen, or intermaxillary segment, the middle segment (from the incisive foramen to the suture transversal to the palatal bone and the posterior segment (after the suture transversal to the palatal bone . Rapid palatal expansion might be recommended for patients at the final pubertal growth stage, in addition to adult patients with maxillary constriction. It represents a treatment solution that can potentially avoid surgical intervention. When performed in association with rapid palatal expanders, it might enhance the skeletal effects of the latter. Of the various designs of expansion appliances, MARPE (miniscrew-assisted rapid palatal expander has been modified in order to allow its operational advantages and outcomes to become familiar in the clinical practice.

  15. Replantation (Finger, Hand, or Arm)

    Science.gov (United States)

    ... the surgical reattachment of a finger, hand or arm that has been completely cut from a person’s ... replanted part if it is further down the arm. Joint vs. non-joint injury . More movement will ...

  16. Rapid learning of magnetic compass direction by C57BL/6 mice in a 4-armed 'plus' water maze.

    Directory of Open Access Journals (Sweden)

    John B Phillips

    Full Text Available Magnetoreception has been demonstrated in all five vertebrate classes. In rodents, nest building experiments have shown the use of magnetic cues by two families of molerats, Siberian hamsters and C57BL/6 mice. However, assays widely used to study rodent spatial cognition (e.g. water maze, radial arm maze have failed to provide evidence for the use of magnetic cues. Here we show that C57BL/6 mice can learn the magnetic direction of a submerged platform in a 4-armed (plus water maze. Naïve mice were given two brief training trials. In each trial, a mouse was confined to one arm of the maze with the submerged platform at the outer end in a predetermined alignment relative to magnetic north. Between trials, the training arm and magnetic field were rotated by 180(° so that the mouse had to swim in the same magnetic direction to reach the submerged platform. The directional preference of each mouse was tested once in one of four magnetic field alignments by releasing it at the center of the maze with access to all four arms. Equal numbers of responses were obtained from mice tested in the four symmetrical magnetic field alignments. Findings show that two training trials are sufficient for mice to learn the magnetic direction of the submerged platform in a plus water maze. The success of these experiments may be explained by: (1 absence of alternative directional cues (2, rotation of magnetic field alignment, and (3 electromagnetic shielding to minimize radio frequency interference that has been shown to interfere with magnetic compass orientation of birds. These findings confirm that mice have a well-developed magnetic compass, and give further impetus to the question of whether epigeic rodents (e.g., mice and rats have a photoreceptor-based magnetic compass similar to that found in amphibians and migratory birds.

  17. Adaptive myoelectric pattern recognition for arm movement in different positions using advanced online sequential extreme learning machine.

    Science.gov (United States)

    Anam, Khairul; Al-Jumaily, Adel

    2016-08-01

    The performance of the myoelectric pattern recognition system sharply decreases when working in various limb positions. The issue can be solved by cumbersome training procedure that can anticipate all possible future situations. However, this procedure will sacrifice the comfort of the user. In addition, many unpredictable scenarios may be met in the future. This paper proposed a new adaptive myoelectric pattern recognition using advance online sequential extreme learning (AOS-ELM) for classification of the hand movements to five different positions. AOS-ELM is an improvement of OS-ELM that can verify the adaptation validity using entropy. The proposed adaptive MPR was able to classify eight different classes from eleven subjects by accuracy of 95.42 % using data from one position. After learning the data from whole positions, the performance of the proposed system is 86.13 %. This performance was better than the MPR that employed original OS-ELM, but it was worse than the MPR that utilized the batch classifiers. Nevertheless, the adaptation mechanism of AOS-ELM is preferred in the real-time application.

  18. Automation of angular movement of the arm neutron diffractometer; Automatizacion del movimiento angular del brazo del difractometro de neutrones

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F.; Herrera A, E.; Quintana C, G. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Torres R, C. E.; Reyes V, M., E-mail: fortunato.aguilar@inin.gob.mx [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Ex-Rancho La Virgen, Metepec, Estado de Mexico (Mexico)

    2015-09-15

    A technique to determine the crystal structure of some materials is the neutron diffraction. This technique consists on placing the material in question in a monoenergetic neutron beam obtained by neutron diffraction in a monochromator crystal. The neutron energy depends of the diffraction angle. The Instituto Nacional de Investigaciones Nucleares has a neutron diffractometer and monochromator crystals of pyrolytic graphite. This crystal can be selecting the neutron energy depending on the angle of diffraction in the glass. The radiation source for the neutron diffractometer is the TRIGA Mark III reactor of the Nuclear Center Dr. Nabor Carrillo Flores. During their operation are also obtained besides neutrons, β and γ radiation. The interest is to have thermal neutrons, so fast neutrons and γ rays are removed using appropriate shielding. The average neutron fluxes of the radial port RE2 of neutron diffractometer at power 1 MW are: heat flow 2,466 x 10{sup 8} n cm{sup -2} sec{sup -1} and fast flow 1,239 x 10{sup 8} n cm{sup -2} sec{sup -1}. The neutron detector is housed in a shield mounted on a mechanical linkage with which the diffraction angle is selected, and therefore the energy of the neutrons. The movement of this joint was performed by the equipment operator manually, so that accuracy to select the diffraction angle was not good and the process rather slow. Therefore a mechanical system was designed, automated by means of a motor as an actuator, a system of force transmission and an electronic control in order that the operator will schedule the diffraction angles and allow the count in the neutrons detection system in a simple manner. (Author)

  19. Auditory inhibition of rapid eye movements and dream recall from REM sleep.

    Science.gov (United States)

    Stuart, Katrina; Conduit, Russell

    2009-03-01

    There is debate in dream research as to whether ponto-geniculo-occipital (PGO) waves or cortical arousal during sleep underlie the biological mechanisms of dreaming. This study comprised 2 experiments. As eye movements (EMs) are currently considered the best noninvasive indicator of PGO burst activity in humans, the aim of the first experiment was to investigate the effect of low-intensity repeated auditory stimulation on EMs (and inferred PGO burst activity) during REM sleep. It was predicted that such auditory stimuli during REM sleep would have a suppressive effect on EMs. The aim of the second experiment was to examine the effects of this auditory stimulation on subsequent dream reporting on awakening. Repeated measures design with counterbalanced order of experimental and control conditions across participants. Sleep laboratory based polysomnography (PSG) PARTICIPANTS: Experiment 1 : 5 males and 10 females aged 18-35 years (M = 20.8, SD = 5.4). Experiment 2 : 7 males and 13 females aged 18-35 years (M = 23.3, SD = 5.5). Below-waking threshold tone presentations during REM sleep compared to control REM sleep conditions without tone presentations. PSG records were manually scored for sleep stages, EEG arousals, and EMs. Auditory stimulation during REM sleep was related to: (a) an increase in EEG arousal, (b) a decrease in the amplitude and frequency of EMs, and (c) a decrease in the frequency of visual imagery reports on awakening. The results of this study provide phenomenological support for PGO-based theories of dream reporting on awakening from sleep in humans.

  20. A comparative study of methods for automatic detection of rapid eye movement abnormal muscular activity in narcolepsy

    DEFF Research Database (Denmark)

    Olesen, Alexander Neergaard; Cesari, Matteo; Christensen, Julie Anja Engelhard

    2018-01-01

    Objective: To evaluate rapid eye movement (REM) muscular activity in narcolepsy by applying five algorithms to electromyogram (EMG) recordings, and to investigate its value for narcolepsy diagnosis. Patients/methods: A modified version of phasic EMG metric (mPEM), muscle activity index (MAI), REM...... atonia index (RAI), supra-threshold REM EMG activit ymetric (STREAM), and Frandsen method (FR) were calculated from polysomnography recordings of 20 healthy controls, 18 clinic controls (subjects suspected with narcolepsy but finally diagnosed without any sleep abnormality), 16 narcolepsy type 1 without...... REM sleep behavior disorder (RBD), 9 narcolepsy type 1 with RBD, and 18 narcolepsy type 2. Diagnostic value of metrics in differentiating between groups was quantified by area under the receiver operating characteristic curve (AUC). Correlations among the metrics and cerebrospinal fluid hypocretin-1...

  1. Center of Pressure Displacement of Standing Posture during Rapid Movements Is Reorganised Due to Experimental Lower Extremity Muscle Pain.

    Directory of Open Access Journals (Sweden)

    Shinichiro Shiozawa

    Full Text Available Postural control during rapid movements may be impaired due to musculoskeletal pain. The purpose of this study was to investigate the effect of experimental knee-related muscle pain on the center of pressure (CoP displacement in a reaction time task condition.Nine healthy males performed two reaction time tasks (dominant side shoulder flexion and bilateral heel lift before, during, and after experimental pain induced in the dominant side vastus medialis or the tibialis anterior muscles by hypertonic saline injections. The CoP displacement was extracted from the ipsilateral and contralateral side by two force plates and the net CoP displacement was calculated.Compared with non-painful sessions, tibialis anterior muscle pain during the peak and peak-to-peak displacement for the CoP during anticipatory postural adjustments (APAs of the shoulder task reduced the peak-to-peak displacement of the net CoP in the medial-lateral direction (P<0.05. Tibialis anterior and vastus medialis muscle pain during shoulder flexion task reduced the anterior-posterior peak-to-peak displacement in the ipsilateral side (P<0.05.The central nervous system in healthy individuals was sufficiently robust in maintaining the APA characteristics during pain, although the displacement of net and ipsilateral CoP in the medial-lateral and anterior-posterior directions during unilateral fast shoulder movement was altered.

  2. A rapid phenol toxicity test based on photosynthesis and movement of the freshwater flagellate, Euglena agilis Carter.

    Science.gov (United States)

    Kottuparambil, Sreejith; Kim, Youn-Jung; Choi, Hoon; Kim, Mi-Sung; Park, Areum; Park, Jihae; Shin, Woongghi; Han, Taejun

    2014-10-01

    Phenol, a monosubstituted aromatic hydrocarbon with various commercial uses, is a major organic constituent in industrial wastewaters. The ecotoxic action of phenol for aquatic environment is well known. In this study, rapid phenol toxicity tests (1h) were developed based on chlorophyll a (Chl a) fluorescence and the movement parameters of the freshwater flagellate, Euglena agilis Carter. Phenol significantly reduced the maximum quantum yield (Fv/Fm) of photosystem II (PS II) and the maximum photosynthetic electron transport rate (rETRmax) with median effective concentration (EC50) values of 8.94 and 4.67 mM, respectively. Phenol reduced the motility and triggered change in the swimming velocity of the test organism. Among the parameters tested, velocity was the most sensitive biomarker with an EC50 of 3.17 mM. The EC50 values for Fv/Fm, motility, and velocity appear to overlap the permitted levels of phenol. In conclusion, the photosynthesis and movement of E. agilis can be fast and sensitive risk assessment parameters for the evaluation of phenol toxicity in municipal and industrial effluents. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Degenerative Encephalopathy in Nova Scotia Duck Tolling Retrievers Presenting with a Rapid Eye Movement Sleep Behavior Disorder.

    Science.gov (United States)

    Barker, E N; Dawson, L J; Rose, J H; Van Meervenne, S; Frykman, O; Rohdin, C; Leijon, A; Soerensen, K E; Järnegren, J; Johnson, G C; O'Brien, D P; Granger, N

    2016-09-01

    Neurodegenerative diseases are a heterogeneous group of disorders characterized by loss of neurons and are commonly associated with a genetic mutation. To characterize the clinical and histopathological features of a novel degenerative neurological disease affecting the brain of young adult Nova Scotia Duck Tolling Retrievers (NSDTRs). Nine, young adult, related NSDTRs were evaluated for neurological dysfunction and rapid eye movement sleep behavior disorder. Case series review. Clinical signs of neurological dysfunction began between 2 months and 5 years of age and were progressive in nature. They were characterized by episodes of marked movements during sleep, increased anxiety, noise phobia, and gait abnormalities. Magnetic resonance imaging documented symmetrical, progressively increasing, T2-weighted image intensity, predominantly within the caudate nuclei, consistent with necrosis secondary to gray matter degeneration. Abnormalities were not detected on clinicopathological analysis of blood and cerebrospinal fluid, infectious disease screening or urine metabolite screening in most cases. Postmortem examination of brain tissue identified symmetrical malacia of the caudate nuclei and axonal dystrophy within the brainstem and spinal cord. Genealogical analysis supports an autosomal recessive mode of inheritance. A degenerative encephalopathy was identified in young adult NSDTRs consistent with a hereditary disease. The prognosis is guarded due to the progressive nature of the disease, which is minimally responsive to empirical treatment. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  4. Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

    Energy Technology Data Exchange (ETDEWEB)

    Miletich, R.S.

    1985-01-01

    The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and /sup 3/H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by ..cap alpha..-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S/sub 2/ episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. /sup 3/H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system.

  5. Alterations in regional cerebral glucose metabolism across waking and non-rapid eye movement sleep in depression.

    Science.gov (United States)

    Nofzinger, Eric A; Buysse, Daniel J; Germain, Anne; Price, Julie C; Meltzer, Carolyn C; Miewald, Jean M; Kupfer, David J

    2005-04-01

    Depression is associated with sleep disturbances, including alterations in non-rapid eye movement (NREM) sleep. Non-rapid eye movement sleep is associated with decreases in frontal, parietal, and temporal cortex metabolic activity compared with wakefulness. To show that depressed patients would have less of a decrease than controls in frontal metabolism between waking and NREM sleep and to show that during NREM sleep, they would have increased activity in structures that promote arousal. Subjects completed electroencephalographic sleep and regional cerebral glucose metabolism assessments during both waking and NREM sleep using [(18)F]fluoro-2-deoxy-D-glucose positron emission tomography. General clinical research center. The study included 29 unmedicated patients who met the Structured Clinical Interview for DSM-IV criteria for current major depression and who had a score of 15 or greater on a 17-item Hamilton Rating Scale for Depression and 28 medically healthy subjects of comparable age and sex who were free of mental disorders. Electroencephalographic sleep and regional cerebral metabolism during waking and NREM sleep. Depressed patients showed smaller decreases than healthy subjects in relative metabolism in broad regions of the frontal, parietal, and temporal cortex from waking to NREM sleep. Depressed patients showed larger decreases than healthy subjects in relative metabolism in the left amygdala, anterior cingulate cortex, cerebellum, parahippocampal cortex, fusiform gyrus, and occipital cortex. However, in post hoc analyses, depressed patients showed hypermetabolism in these areas during both waking and NREM sleep. The smaller decrease in frontal metabolism from waking to NREM sleep in depressed patients is further evidence for a dynamic sleep-wake alteration in prefrontal cortex function in depression. Hypermetabolism in a ventral emotional neural system during waking in depressed patients persists into NREM sleep.

  6. Repeated Administration of Korea Red Ginseng Extract Increases Non-Rapid Eye Movement Sleep via GABAAergic Systems.

    Science.gov (United States)

    Lee, Chung-Il; Kim, Chung-Soo; Han, Jin-Yi; Oh, Eun-Hye; Oh, Ki-Wan; Eun, Jae Soon

    2012-10-01

    The current inquiry was conducted to assess the change in sleep architecture after long periods of administration to determine whether ginseng can be used in the therapy of sleeplessness. Following post-surgical recovery, red ginseng extract (RGE, 200 mg/ kg) was orally administrated to rats for 9 d. Data were gathered on the 1st, 5th, and 9th day, and an electroencephalogram was recorded 24 h after RGE administration. Polygraphic signs of unobstructed sleep-wake activities were simultaneously recorded with sleep-wake recording electrodes from 11:00 a.m. to 5:00 p.m. for 6 h. Rodents were generally tamed to freely moving polygraphic recording conditions. Although the 1st and 5th day of RGE treatment showed no effect on power densities in non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, the 9th day of RGE administration showed augmented α-wave (8.0 to 13.0 Hz) power densities in NREM and REM sleep. RGE increased total sleep and NREM sleep. The total percentage of wakefulness was only decreased on the 9th day, and the number of sleep-wake cycles was reduced after the repeated administration of RGE. Thus, the repeated administration of RGE increased NREM sleep in rats. The α-wave activities in the cortical electroencephalograms were increased in sleep architecture by RGE. Moreover, the levels of both α- and β-subunits of the γ-aminobutyric acid (GABA)A receptor were reduced in the hypothalamus of the RGE-treated groups. The level of glutamic acid decarboxylase was over-expressed in the hypothalamus. These results demonstrate that RGE increases NREM sleep via GABAAergic systems.

  7. Reduction in ultrasonic vocalizations in pups born to rapid eye movement sleep restricted mothers in rat model.

    Directory of Open Access Journals (Sweden)

    Kamalesh K Gulia

    Full Text Available The effects of rapid eye movement sleep restriction (REMSR in rats during late pregnancy were studied on the ultrasonic vocalizations (USVs made by the pups. USVs are distress calls inaudible to human ears. Rapid eye movement (REM sleep was restricted in one group of pregnant rats for 22 hours, starting from gestational day 14 to 20, using standard single platform method. The USVs of male pups were recorded after a brief isolation from their mother for two minutes on alternate post-natal days, from day one till weaning. The USVs were recorded using microphones and were analysed qualitatively and quantitatively using SASPro software. Control pups produced maximum vocalization on post-natal days 9 to 11. In comparison, the pups born to REMSR mothers showed not only a reduction in vocalization but also a delay in peak call making days. The experimental group showed variations in the types and characteristics of call types, and alteration in temporal profile. The blunting of distress call making response in these pups indicates that maternal sleep plays a role in regulating the neural development involved in vocalizations and possibly in shaping the emotional behaviour in neonates. It is suggested that the reduced ultrasonic vocalizations can be utilized as a reliable early marker for affective state in rat pups. Such impaired vocalization responses could provide an important lead in understanding mother-child bonding for an optimal cognitive development during post-partum life. This is the first report showing a potential link between maternal REM sleep deprivation and the vocalization in neonates and infants.

  8. Reduction in ultrasonic vocalizations in pups born to rapid eye movement sleep restricted mothers in rat model.

    Science.gov (United States)

    Gulia, Kamalesh K; Patel, Niraj; Radhakrishnan, Arathi; Kumar, Velayudhan Mohan

    2014-01-01

    The effects of rapid eye movement sleep restriction (REMSR) in rats during late pregnancy were studied on the ultrasonic vocalizations (USVs) made by the pups. USVs are distress calls inaudible to human ears. Rapid eye movement (REM) sleep was restricted in one group of pregnant rats for 22 hours, starting from gestational day 14 to 20, using standard single platform method. The USVs of male pups were recorded after a brief isolation from their mother for two minutes on alternate post-natal days, from day one till weaning. The USVs were recorded using microphones and were analysed qualitatively and quantitatively using SASPro software. Control pups produced maximum vocalization on post-natal days 9 to 11. In comparison, the pups born to REMSR mothers showed not only a reduction in vocalization but also a delay in peak call making days. The experimental group showed variations in the types and characteristics of call types, and alteration in temporal profile. The blunting of distress call making response in these pups indicates that maternal sleep plays a role in regulating the neural development involved in vocalizations and possibly in shaping the emotional behaviour in neonates. It is suggested that the reduced ultrasonic vocalizations can be utilized as a reliable early marker for affective state in rat pups. Such impaired vocalization responses could provide an important lead in understanding mother-child bonding for an optimal cognitive development during post-partum life. This is the first report showing a potential link between maternal REM sleep deprivation and the vocalization in neonates and infants.

  9. Coordination of multiple robot arms

    Science.gov (United States)

    Barker, L. K.; Soloway, D.

    1987-01-01

    Kinematic resolved-rate control from one robot arm is extended to the coordinated control of multiple robot arms in the movement of an object. The structure supports the general movement of one axis system (moving reference frame) with respect to another axis system (control reference frame) by one or more robot arms. The grippers of the robot arms do not have to be parallel or at any pre-disposed positions on the object. For multiarm control, the operator chooses the same moving and control reference frames for each of the robot arms. Consequently, each arm then moves as though it were carrying out the commanded motions by itself.

  10. Noradrenergic modulation of masseter muscle activity during natural rapid eye movement sleep requires glutamatergic signalling at the trigeminal motor nucleus

    Science.gov (United States)

    Schwarz, Peter B; Mir, Saba; Peever, John H

    2014-01-01

    Noradrenergic neurotransmission in the brainstem is closely coupled to changes in muscle activity across the sleep–wake cycle, and noradrenaline is considered to be a key excitatory neuromodulator that reinforces the arousal-related stimulus on motoneurons to drive movement. However, it is unknown if α-1 noradrenoceptor activation increases motoneuron responsiveness to excitatory glutamate (AMPA) receptor-mediated inputs during natural behaviour. We studied the effects of noradrenaline on AMPA receptor-mediated motor activity at the motoneuron level in freely behaving rats, particularly during rapid eye movement (REM) sleep, a period during which both AMPA receptor-triggered muscle twitches and periods of muscle quiescence in which AMPA drive is silent are exhibited. Male rats were subjected to electromyography and electroencephalography recording to monitor sleep and waking behaviour. The implantation of a cannula into the trigeminal motor nucleus of the brainstem allowed us to perfuse noradrenergic and glutamatergic drugs by reverse microdialysis, and thus to use masseter muscle activity as an index of motoneuronal output. We found that endogenous excitation of both α-1 noradrenoceptor and AMPA receptors during waking are coupled to motor activity; however, REM sleep exhibits an absence of endogenous α-1 noradrenoceptor activity. Importantly, exogenous α-1 noradrenoceptor stimulation cannot reverse the muscle twitch suppression induced by AMPA receptor blockade and nor can it elevate muscle activity during quiet REM, a phase when endogenous AMPA receptor activity is subthreshold. We conclude that the presence of an endogenous glutamatergic drive is necessary for noradrenaline to trigger muscle activity at the level of the motoneuron in an animal behaving naturally. PMID:24860176

  11. A novel non-rapid-eye movement and rapid-eye-movement parasomnia with sleep breathing disorder associated with antibodies to IgLON5: a case series, characterisation of the antigen, and post-mortem study.

    Science.gov (United States)

    Sabater, Lidia; Gaig, Carles; Gelpi, Ellen; Bataller, Luis; Lewerenz, Jan; Torres-Vega, Estefanía; Contreras, Angeles; Giometto, Bruno; Compta, Yaroslau; Embid, Cristina; Vilaseca, Isabel; Iranzo, Alex; Santamaría, Joan; Dalmau, Josep; Graus, Francesc

    2014-06-01

    Autoimmunity might be associated with or implicated in sleep and neurodegenerative disorders. We aimed to describe the features of a novel neurological syndrome associated with prominent sleep dysfunction and antibodies to a neuronal antigen. In this observational study, we used clinical and video polysomnography to identify a novel sleep disorder in three patients referred to the Sleep Unit of Hospital Clinic, University of Barcelona, Spain, for abnormal sleep behaviours and obstructive sleep apnoea. These patients had antibodies against a neuronal surface antigen, which were also present in five additional patients referred to our laboratory for antibody studies. These five patients had been assessed with polysomnography, which was done in our sleep unit in one patient and the recording reviewed in a second patient. Two patients underwent post-mortem brain examination. Immunoprecipitation and mass spectrometry were used to characterise the antigen and develop an assay for antibody testing. Serum or CSF from 298 patients with neurodegenerative, sleep, or autoimmune disorders served as control samples. All eight patients (five women; median age at disease onset 59 years [range 52-76]) had abnormal sleep movements and behaviours and obstructive sleep apnoea, as confirmed by polysomnography. Six patients had chronic progression with a median duration from symptom onset to death or last visit of 5 years (range 2-12); in four the sleep disorder was the initial and most prominent feature, and in two it was preceded by gait instability followed by dysarthria, dysphagia, ataxia, or chorea. Two patients had a rapid progression with disequilibrium, dysarthria, dysphagia, and central hypoventilation, and died 2 months and 6 months, respectively, after symptom onset. In five of five patients, video polysomnography showed features of obstructive sleep apnoea, stridor, and abnormal sleep architecture (undifferentiated non-rapid-eye-movement [non-REM] sleep or poorly structured

  12. Baseline Levels of Rapid Eye Movement Sleep May Protect Against Excessive Activity in Fear-Related Neural Circuitry.

    Science.gov (United States)

    Lerner, Itamar; Lupkin, Shira M; Sinha, Neha; Tsai, Alan; Gluck, Mark A

    2017-11-15

    Sleep, and particularly rapid eye movement sleep (REM), has been implicated in the modulation of neural activity following fear conditioning and extinction in both human and animal studies. It has long been presumed that such effects play a role in the formation and persistence of posttraumatic stress disorder, of which sleep impairments are a core feature. However, to date, few studies have thoroughly examined the potential effects of sleep prior to conditioning on subsequent acquisition of fear learning in humans. Furthermore, these studies have been restricted to analyzing the effects of a single night of sleep-thus assuming a state-like relationship between the two. In the current study, we used long-term mobile sleep monitoring and functional neuroimaging (fMRI) to explore whether trait-like variations in sleep patterns, measured in advance in both male and female participants, predict subsequent patterns of neural activity during fear learning. Our results indicate that higher baseline levels of REM sleep predict reduced fear-related activity in, and connectivity between, the hippocampus, amygdala and ventromedial PFC during conditioning. Additionally, skin conductance responses (SCRs) were weakly correlated to the activity in the amygdala. Conversely, there was no direct correlation between REM sleep and SCRs, indicating that REM may only modulate fear acquisition indirectly. In a follow-up experiment, we show that these results are replicable, though to a lesser extent, when measuring sleep over a single night just before conditioning. As such, baseline sleep parameters may be able to serve as biomarkers for resilience, or lack thereof, to trauma. SIGNIFICANCE STATEMENT Numerous studies over the past two decades have established a clear role of sleep in fear-learning processes. However, previous work has focused on the effects of sleep following fear acquisition, thus neglecting the potential effects of baseline sleep levels on the acquisition itself. The

  13. Comparison of three-dimensional, assist-as-needed robotic arm/hand movement training provided with Pneu-WREX to conventional tabletop therapy after chronic stroke.

    Science.gov (United States)

    Reinkensmeyer, David J; Wolbrecht, Eric T; Chan, Vicky; Chou, Cathy; Cramer, Steven C; Bobrow, James E

    2012-11-01

    Robot-assisted movement training can help individuals with stroke reduce arm and hand impairment, but robot therapy is typically only about as effective as conventional therapy. Refining the way that robots assist during training may make them more effective than conventional therapy. Here, the authors measured the therapeutic effect of a robot that required individuals with a stroke to achieve virtual tasks in three dimensions against gravity. The robot continuously estimated how much assistance patients needed to perform the tasks and provided slightly less assistance than needed to reduce patient slacking. Individuals with a chronic stroke (n = 26; baseline upper limb Fugl-Meyer score, 23 ± 8) were randomized into two groups and underwent 24 one-hour training sessions over 2 mos. One group received the assist-as-needed robot training and the other received conventional tabletop therapy with the supervision of a physical therapist. Training helped both groups significantly reduce their motor impairment, as measured by the primary outcome measure, the Fugl-Meyer score, but the improvement was small (3.0 ± 4.9 points for robot therapy vs. 0.9 ± 1.7 for conventional therapy). There was a trend for greater reduction for the robot-trained group (P = 0.07). The robot group largely sustained this gain at the 3-mo follow-up. The robot-trained group also experienced significant improvements in Box and Blocks score and hand grip strength, whereas the control group did not, but these improvements were not sustained at follow-up. In addition, the robot-trained group showed a trend toward greater improvement in sensory function, as measured by the Nottingham Sensory Test (P = 0.06). These results suggest that in patients with chronic stroke and moderate-severe deficits, assisting in three-dimensional virtual tasks with an assist-as-needed controller may make robotic training more effective than conventional tabletop training.

  14. Early detection of Parkinson’s diseases by using the relation between time response and movement characteristics of human’s arms

    Directory of Open Access Journals (Sweden)

    Prasert Namwet

    2016-08-01

    Full Text Available Parkinson’s and stroke diseases are closely linked to the brain of the elderly. This study was to investigate the early detecting method of Parkinson’s disease by using the relation between the brain time response and the arm movement characteristics. 120 Healthy people were examined and classified into 4 groups of ages (60 years old.The relationship between the two parameters were conducted by using the self-made electronics set which had an accelerometer attached on the hammer; and pattern generator using star-pattern with 9-position lighted keypad. Several simple and complex light patterns were designed to test the brain function of the elderly. The experimental treatments were subjected to 4×2 Factorial Experiment in Completely Randomized Design (CRD. The results showed that the time response of the group of+60’s years old was the longest compared with other group with P<0.01. Based on the experiments on pattern-position approach, those selected samples with 4 groups of age completed the experiment with a sample pattern faster than the complex pattern in all 4 groups of age with P<0.01. The acceleration signal’s patterns in 20-40 years old and +60 years old were found polynomial and linear signal patterns, respectively. The relationship between the time response and acceleration signal were found negative monotonic correlated ( = 0.835, P < 0.01. Therefore, this finding could identify the healthy people without Parkinson’s disease with accuracy of 99.58 %. The results could be concluded that relationship between the time response and the acceleration signal could predict Parkinson’s disease and related diseases in the future.

  15. Acute administration of fluoxetine normalizes rapid eye movement sleep abnormality, but not depressive behaviors in olfactory bulbectomized rats.

    Science.gov (United States)

    Wang, Yi-Qun; Tu, Zhi-Cai; Xu, Xing-Yuan; Li, Rui; Qu, Wei-Min; Urade, Yoshihiro; Huang, Zhi-Li

    2012-01-01

    In humans, depression is associated with altered rapid eye movement (REM) sleep. However, the exact nature of the relationship between depressive behaviors and sleep abnormalities is debated. In this study, bilateral olfactory bulbectomy (OBX) was carried out to create a model of depression in rats. The sleep-wake profiles were assayed using a cutting-edge sleep bioassay system, and depressive behaviors were evaluated by open field and forced swimming tests. The monoamine content and monoamine metabolite levels in the brain were determined by a HPLC-electrochemical detection system. OBX rats exhibited a significant increase in REM sleep, especially between 15:00 and 18:00 hours during the light period. Acute treatment with fluoxetine (10 mg/kg, i.p.) immediately abolished the OBX-induced increase in REM sleep, but hyperactivity in the open field test and the time spent immobile in the forced swimming test remained unchanged. Neurochemistry studies revealed that acute administration of fluoxetine increased serotonin (5-HT) levels in the hippocampus, thalamus, and midbrain and decreased levels of the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA). The ratio of 5-HIAA to 5-HT decreased in almost all regions of the brain. These results indicate that acute administration of fluoxetine can reduce the increase in REM sleep but does not change the depressive behaviors in OBX rats, suggesting that there was no causality between REM sleep abnormalities and depressive behaviors in OBX rats. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

  16. Why Are Seizures Rare in Rapid Eye Movement Sleep? Review of the Frequency of Seizures in Different Sleep Stages

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    Marcus Ng

    2013-01-01

    Full Text Available Since the formal characterization of sleep stages, there have been reports that seizures may preferentially occur in certain phases of sleep. Through ascending cholinergic connections from the brainstem, rapid eye movement (REM sleep is physiologically characterized by low voltage fast activity on the electroencephalogram, REMs, and muscle atonia. Multiple independent studies confirm that, in REM sleep, there is a strikingly low proportion of seizures (~1% or less. We review a total of 42 distinct conventional and intracranial studies in the literature which comprised a net of 1458 patients. Indexed to duration, we found that REM sleep was the most protective stage of sleep against focal seizures, generalized seizures, focal interictal discharges, and two particular epilepsy syndromes. REM sleep had an additional protective effect compared to wakefulness with an average 7.83 times fewer focal seizures, 3.25 times fewer generalized seizures, and 1.11 times fewer focal interictal discharges. In further studies REM sleep has also demonstrated utility in localizing epileptogenic foci with potential translation into postsurgical seizure freedom. Based on emerging connectivity data in sleep, we hypothesize that the influence of REM sleep on seizures is due to a desynchronized EEG pattern which reflects important connectivity differences unique to this sleep stage.

  17. Effects of partial sleep deprivation on slow waves during non-rapid eye movement sleep: A high density EEG investigation.

    Science.gov (United States)

    Plante, David T; Goldstein, Michael R; Cook, Jesse D; Smith, Richard; Riedner, Brady A; Rumble, Meredith E; Jelenchick, Lauren; Roth, Andrea; Tononi, Giulio; Benca, Ruth M; Peterson, Michael J

    2016-02-01

    Changes in slow waves during non-rapid eye movement (NREM) sleep in response to acute total sleep deprivation are well-established measures of sleep homeostasis. This investigation utilized high-density electroencephalography (hdEEG) to examine topographic changes in slow waves during repeated partial sleep deprivation. Twenty-four participants underwent a 6-day sleep restriction protocol. Spectral and period-amplitude analyses of sleep hdEEG data were used to examine changes in slow wave energy, count, amplitude, and slope relative to baseline. Changes in slow wave energy were dependent on the quantity of NREM sleep utilized for analysis, with widespread increases during sleep restriction and recovery when comparing data from the first portion of the sleep period, but restricted to recovery sleep if the entire sleep episode was considered. Period-amplitude analysis was less dependent on the quantity of NREM sleep utilized, and demonstrated topographic changes in the count, amplitude, and distribution of slow waves, with frontal increases in slow wave amplitude, numbers of high-amplitude waves, and amplitude/slopes of low amplitude waves resulting from partial sleep deprivation. Topographic changes in slow waves occur across the course of partial sleep restriction and recovery. These results demonstrate a homeostatic response to partial sleep loss in humans. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  18. Abnormal response of melanin-concentrating hormone deficient mice to fasting: hyperactivity and rapid eye movement sleep suppression.

    Science.gov (United States)

    Willie, J T; Sinton, C M; Maratos-Flier, E; Yanagisawa, M

    2008-10-28

    Melanin-concentrating hormone (MCH) is a hypothalamic neuropeptide that has been implicated in energy homeostasis. Pharmacological studies with MCH and its receptor antagonists have suggested additional behavioral roles for the neuropeptide in the control of mood and vigilance states. These suggestions have been supported by a report of modified sleep in the MCH-1 receptor knockout mouse. Here we found that MCH knockout (MCH(-)(/)(-)) mice slept less during both the light and dark phases under baseline conditions. In response to fasting, MCH(-)(/)(-) mice exhibited marked hyperactivity, accelerated weight loss and an exaggerated decrease in rapid eye movement (REM) sleep. Following a 6-h period of sleep deprivation, however, the sleep rebound in MCH(-)(/)(-) mice was normal. Thus MCH(-)(/)(-) mice adapt poorly to fasting, and their loss of bodyweight under this condition is associated with behavioral hyperactivity and abnormal expression of REM sleep. These results support a role for MCH in vigilance state regulation in response to changes in energy homeostasis and may relate to a recent report of initial clinical trials with a novel MCH-1 receptor antagonist. When combined with caloric restriction, the treatment of healthy, obese subjects with this compound resulted in some subjects experiencing vivid dreams and sleep disturbances.

  19. Retinal nerve fiber layer thinning: a window into rapid eye movement sleep behavior disorders in Parkinson's disease.

    Science.gov (United States)

    Yang, Zi-Jiao; Wei, Jing; Mao, Cheng-Jie; Zhang, Jin-Ru; Chen, Jing; Ji, Xiao-Yan; Liu, Jun-Yi; Shen, Yun; Xiong, Kang-Ping; Huang, Jun-Ying; Yang, Ya-Ping; Liu, Chun-Feng

    2016-12-01

    Retinal nerve fiber layer (RNFL) thinning occurs in Parkinson's disease (PD) and other neurodegenerative diseases. Idiopathic RBD (iRBD) is a well-established prodromal hallmark of synucleinopathies and occurs secondary to many neurodegenerative diseases, including PD. The aim of this study is to determine whether or not retinal structures are altered with the onset of rapid eye movement (REM) sleep behavior disorders (RBD). In all, a total of 63 patients with PD, 14 patients with idiopathic RBD, and 26 sex- and age-matched healthy controls were enrolled and underwent optical coherence tomography measurements (HD-OCT (Zeiss) ) for the average and every quadrant of RNFL thickness. The REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ) was used to classify PD patients with clinically probable RBD (PD + pRBD) or without probable RBD (PD - pRBD). Patients with iRBD were identified by polysomnography. For patients with RBD (idiopathic or secondary to PD), we found a significant decrease in RNFL thickness compared with groups without RBD (PD - pRBD and healthy controls) (all p treatment. Multiple linear regression analysis showed that RBDSQ score was negatively associated with average and inferior RNFL variation in PD (all p < 0.005). The findings show that RNFL was slightly but significantly thinner in idiopathic RBD. In PD, RNFL thickness may vary depending on the presence of RBD.

  20. Effects of partial sleep deprivation on slow waves during non-rapid eye movement sleep: a high density EEG investigation

    Science.gov (United States)

    Plante, David T.; Goldstein, Michael R.; Cook, Jesse D.; Smith, Richard; Riedner, Brady A.; Rumble, Meredith E.; Jelenchick, Lauren; Roth, Andrea; Tononi, Giulio; Benca, Ruth M.; Peterson, Michael J.

    2015-01-01

    Objective Changes in slow waves during non-rapid eye movement (NREM) sleep in response to acute total sleep deprivation are well-established measures of sleep homeostasis. This investigation utilized high-density electroencephalography (hdEEG) to examine topographic changes in slow waves during repeated partial sleep deprivation. Methods Twenty-four participants underwent a 6-day sleep restriction protocol. Spectral and period-amplitude analyses of sleep hdEEG data were used to examine changes in slow wave energy, count, amplitude, and slope relative to baseline. Results Changes in slow wave energy were dependent on the quantity of NREM sleep utilized for analysis, with widespread increases during sleep restriction and recovery when comparing data from the first portion of the sleep period, but restricted to recovery sleep if the entire sleep episode was considered. Period-amplitude analysis was less dependent on the quantity of NREM sleep utilized, and demonstrated topographic changes in the count, amplitude, and distribution of slow waves, with frontal increases in slow wave amplitude, numbers of high-amplitude waves, and amplitude/slopes of low amplitude waves resulting from partial sleep deprivation. Conclusions Topographic changes in slow waves occur across the course of partial sleep restriction and recovery. Significance These results demonstrate a homeostatic response to partial sleep loss in humans. PMID:26596212

  1. The effects of social housing on extinction of fear conditioning in rapid eye movement sleep-deprived rats.

    Science.gov (United States)

    Hunter, Amy Silvestri

    2014-05-01

    Both human and animal research indicate that rapid eye movement sleep (REM) plays an important role in the processing of emotional information. REM is altered after fear conditioning in rats, but this alteration can be mitigated by exposure to a naïve conspecific. In addition, both the housing condition (isolated vs paired) and the experiences of rats' cagemates can influence the response to aversive events. Based on this prior work, the present study sought to determine the effects of social housing on the previously demonstrated impairment in the extinction of conditioned fear responses produced by REM deprivation. Rats were assigned to one of three housing conditions: housed with a naïve rat, housed with another fear-conditioned rat, or housed alone. The results demonstrated that rats housed with either a naïve or a fear-conditioned conspecific exhibited an impairment in the acquisition of extinction as a consequence of REM deprivation, as observed in previous studies. However, rats in the isolated condition demonstrated a trend toward an impairment only after continued extinction training. These results indicate that the effects of social housing on REM deprivation-induced impairments in learning and memory are subtle, but may explain some conflicting findings in the literature.

  2. Heterochronic shifts in germband movements contribute to the rapid embryonic development of the coffin fly Megaselia scalaris.

    Science.gov (United States)

    Wotton, Karl R

    2014-11-01

    The coffin fly, Megaselia scalaris, is a species of medical and forensic importance and is increasingly being used for the study of genetics. Postmortem interval can be estimated based on the life stage of M. scalaris recovered from corpses, therefore many studies have addressed the duration of each life stage. These studies demonstrate that embryogenesis completes significantly faster in M. scalaris than in the congener Megaselia abdita and faster even than the 24 h needed for Drosophila melanogaster embryogenesis. However, until now it has been unclear if this increased speed is achieved by reducing developmental time across all embryonic stages or by the acceleration of individual stages and processes. Here I use time-lapse imaging to create a staging scheme for M. scalaris embryogenesis. Comparison of stages between D. melanogaster and both Megaselia species reveals that heterochronic shifts, simultaneous morphogenetic movements and compression of individual stages all contribute to the rapid development of M. scalaris. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Rapid eye movement sleep deprivation disrupts consolidation but not reconsolidation of novel object recognition memory in rats.

    Science.gov (United States)

    Chen, Lin; Tian, Shaowen; Ke, Jie

    2014-03-20

    There is increasing evidence that sleep plays a critical role in memory consolidation. However, there are comparatively few studies that have assessed the relationship between sleep and memory reconsolidation. In the present study, we explored the effects of rapid eye movement sleep deprivation (RSD) on the consolidation (experiment 1) and reconsolidation (experiment 2) of novel object recognition memory in rats. In experiment 1 behavioral procedure involved two training phases: sample and test. Rats were subjected to 6h RSD starting either immediately after sample (exposed to 2 objects) or 6h later. In experiment 2 behavioral procedure involved three training phases: sample, reactivation and test. Rats were subjected to 6h RSD starting either immediately after reactivation (exposed to the same 2 sample objects to reactivate the memory trace) or 6h later. Results from experiment 1 showed that post-sample RSD from 0 to 6h but not 6 to 12h disrupted novel object recognition memory consolidation. However, we found that post-reactivation RSD whether from 0 to 6h or 6 to 12h had no effect on novel object recognition memory reconsolidation in experiment 2. The results indicated that RSD selectively disrupted consolidation of novel object recognition memory, suggesting a dissociation effect of RSD on consolidation and reconsolidation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Nocturnal agitation in Huntington disease is caused by arousal-related abnormal movements rather than by rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Neutel, Dulce; Tchikviladzé, Maya; Charles, Perrine; Leu-Semenescu, Smaranda; Roze, Emmanuel; Durr, Alexandra; Arnulf, Isabelle

    2015-06-01

    Patients with Huntington disease (HD) and their spouses often complain of agitation during sleep, but the causes are mostly unknown. To evaluate sleep and nocturnal movements in patients with various HD stages and CAG repeats length. The clinical features and sleep studies of 29 patients with HD were retrospectively collected (11 referred for genotype-phenotype correlations and 18 for agitation during sleep) and compared with those of 29 age- and sex-matched healthy controls. All patients had videopolysomnography, but the movements during arousals were re-analyzed in six patients with HD with stored video. The patients had a longer total sleep period and REM sleep onset latency, but no other differences in sleep than controls. There was no correlation between CAG repeat length and sleep measures, but total sleep time and sleep efficiency were lower in the subgroup with moderate than milder form of HD. Periodic limb movements and REM sleep behavior disorders were excluded, although 2/29 patients had abnormal REM sleep without atonia. In contrast, they had clumsy and opisthotonos-like movements during arousals from non-REM or REM sleep. Some movements were violent and harmful. They might consist of voluntary movements inappropriately involving the proximal part of the limbs on a background of exaggerated hypotonia. Giant (>65 mcV) sleep spindles were observed in seven (24%) patients with HD and one control. The nocturnal agitation in patients with HD seems related to anosognostic voluntary movements on arousals, rather than to REM sleep behavior disorder and other sleep problems. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Rapid eye movement sleep behavior disorder: devising controlled active treatment studies for symptomatic and neuroprotective therapy--a consensus statement from the International Rapid Eye Movement Sleep Behavior Disorder Study Group.

    Science.gov (United States)

    Schenck, C H; Montplaisir, J Y; Frauscher, B; Hogl, B; Gagnon, J-F; Postuma, R; Sonka, K; Jennum, P; Partinen, M; Arnulf, I; Cochen de Cock, V; Dauvilliers, Y; Luppi, P-H; Heidbreder, A; Mayer, G; Sixel-Döring, F; Trenkwalder, C; Unger, M; Young, P; Wing, Y K; Ferini-Strambi, L; Ferri, R; Plazzi, G; Zucconi, M; Inoue, Y; Iranzo, A; Santamaria, J; Bassetti, C; Möller, J C; Boeve, B F; Lai, Y Y; Pavlova, M; Saper, C; Schmidt, P; Siegel, J M; Singer, C; St Louis, E; Videnovic, A; Oertel, W

    2013-08-01

    We aimed to provide a consensus statement by the International Rapid Eye Movement Sleep Behavior Disorder Study Group (IRBD-SG) on devising controlled active treatment studies in rapid eye movement sleep behavior disorder (RBD) and devising studies of neuroprotection against Parkinson disease (PD) and related neurodegeneration in RBD. The consensus statement was generated during the fourth IRBD-SG symposium in Marburg, Germany in 2011. The IRBD-SG identified essential methodologic components for a randomized trial in RBD, including potential screening and diagnostic criteria, inclusion and exclusion criteria, primary and secondary outcomes for symptomatic therapy trials (particularly for melatonin and clonazepam), and potential primary and secondary outcomes for eventual trials with disease-modifying and neuroprotective agents. The latter trials are considered urgent, given the high conversion rate from idiopathic RBD (iRBD) to Parkinsonian disorders (i.e., PD, dementia with Lewy bodies [DLB], multiple system atrophy [MSA]). Six inclusion criteria were identified for symptomatic therapy and neuroprotective trials: (1) diagnosis of RBD needs to satisfy the International Classification of Sleep Disorders, second edition, (ICSD-2) criteria; (2) minimum frequency of RBD episodes should preferably be ⩾2 times weekly to allow for assessment of change; (3) if the PD-RBD target population is included, it should be in the early stages of PD defined as Hoehn and Yahr stages 1-3 in Off (untreated); (4) iRBD patients with soft neurologic dysfunction and with operational criteria established by the consensus of study investigators; (5) patients with mild cognitive impairment (MCI); and (6) optimally treated comorbid OSA. Twenty-four exclusion criteria were identified. The primary outcome measure for RBD treatment trials was determined to be the Clinical Global Impression (CGI) efficacy index, consisting of a four-point scale with a four-point side-effect scale. Assessment of

  6. Sleep spindles and rapid eye movement sleep as predictors of next morning cognitive performance in healthy middle-aged and older participants.

    Science.gov (United States)

    Lafortune, Marjolaine; Gagnon, Jean-François; Martin, Nicolas; Latreille, Véronique; Dubé, Jonathan; Bouchard, Maude; Bastien, Célyne; Carrier, Julie

    2014-04-01

    Spindles and slow waves are hallmarks of non-rapid eye movement sleep. Both these oscillations are markers of neuronal plasticity, and play a role in memory and cognition. Normal ageing is associated with spindle and slow wave decline and cognitive changes. The present study aimed to assess whether spindle and slow wave characteristics during a baseline night predict cognitive performance in healthy older adults the next morning. Specifically, we examined performance on tasks measuring selective and sustained visual attention, declarative verbal memory, working memory and verbal fluency. Fifty-eight healthy middle-aged and older adults (aged 50-91 years) without sleep disorders underwent baseline polysomnographic sleep recording followed by neuropsychological assessment the next morning. Spindles and slow waves were detected automatically on artefact-free non-rapid eye movement sleep electroencephalogram. All-night stage N2 spindle density (no./min) and mean frequency (Hz) and all-night non-rapid eye movement sleep slow wave density (no./min) and mean slope (μV/s) were analysed. Pearson's correlations were performed between spindles, slow waves, polysomnography and cognitive performance. Higher spindle density predicted better performance on verbal learning, visual attention and verbal fluency, whereas spindle frequency and slow wave density or slope predicted fewer cognitive performance variables. In addition, rapid eye movement sleep duration was associated with better verbal learning potential. These results suggest that spindle density is a marker of cognitive functioning in older adults and may reflect neuroanatomic integrity. Rapid eye movement sleep may be a marker of age-related changes in acetylcholine transmission, which plays a role in new information encoding. © 2013 European Sleep Research Society.

  7. Characteristics of early- and late-onset rapid eye movement sleep behavior disorder in China: a case-control study.

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    Zhou, Junying; Zhang, Jihui; Du, Lina; Li, Zhe; Li, Yun; Lei, Fei; Wing, Yun-Kwok; Kushida, Clete A; Zhou, Dong; Tang, Xiangdong

    2014-06-01

    To investigate demography and clinic and polysomnographic characteristics in Chinese rapid eye movement (REM) sleep behavior disorder (RBD) patients across onset ages. Ninety consecutive patients fulfilling the criteria for RBD were recruited for study in our sleep center. Patients were separated into early- and late-onset groups according to age when symptoms began (50 years, respectively). Ninety age- and gender-matched healthy subjects served as controls. All subjects were interviewed for their clinical history, completed an RBD questionnaire, and underwent an overnight video polysomnography assessment. Demographics, comorbidities, scores on the RBD questionnaire, sleep architecture, and EMG activity were compared between the patients and controls and between the early- and late-onset groups. Of all RBD patients, 63 were male, and mean age of RBD onset was 54.3±15.7 years. In 25 patients (28%), RBD was secondary and associated with neurodegenerative disease, narcolepsy or antidepressant use. Twenty-three patients (26%) had early-onset RBD and 67 (74%) were in the late-onset group. RBD patients had significantly more comorbidities, dreams and dream-enacting behaviors, and poorer sleep quality than did controls. The early-onset group had a high proportion of females (48%) and an increased proportion of cases associated with narcolepsy. The early-onset group also had fewer movements, lower EMG activity during REM sleep, and better sleep quality when compared to the late-onset group. EMG activity was positively correlated with age of onset. The mean follow-up time was 1.57±0.82 years, and four patients in the late-onset group were subsequently diagnosed with neurodegenerative diseases. Stratifying patients into early and late-onset RBD revealed different characteristics from those previously described as typical for RBD. EMG activity during REM sleep was positively correlated with age of onset. We suggest that it will be valuable to explore the relationship

  8. Rapid eye movement sleep behaviour disorder in young- and older-onset Parkinson disease: a questionnaire-based study.

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    Mahale, R; Yadav, R; Pal, P K

    2014-06-01

    Rapid eye movement sleep behavior disorder (RBD) is common in Parkinson disease (PD). To determine the frequency of clinically probable RBD (cpRBD) in young-onset (21 to 40 years; OOPD) and characterize its pattern. A total of 156 patients with PD (YOPD-51, OOPD-105) were clinically examined and the presence of RBD was diagnosed using the minimal criteria for diagnosis of RBD (International Classification of Sleep Disorders, ICSD-1). RBD screening questionnaire based on the minimal criteria was used. The bed-partners were also interviewed with Mayo sleep questionnaire. Other scales included Unified Parkinson Disease Rating Scale part III (UPDRS III), Hoehn & Yahr stage, Mini Mental Status Examination, Pittsburgh Sleep Quality Index, Parkinson Disease Sleep Scale, Epworth Sleep Scale, Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale. cpRBD was diagnosed in 30 (19.2%) patients, majority being OOPD rather than YOPD (86.7% vs. 13.3%; P=0.01). The frequency of RBD was significantly higher (P=0.016) in OOPD (24.8%) compared to those with YOPD (7.8%). Most often (72.4%) RBD occurred after the onset of parkinsonian symptoms. RBD was independently associated with higher global PSQI scores, total ESS scores and total PDSS scores after adjusting for the effects of age, gender, Hoehn & Yahr stage and duration of illness. Patients with RBD were older with later-onset motor symptoms, a more advanced stage, poorer sleep quality, and more frequent daytime sleepiness. Older-onset PD had a higher frequency of RBD than young-onset PD. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Allergic rhinitis affects the duration of rapid eye movement sleep in children with sleep-disordered breathing without sleep apnea.

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    Di Francesco, Renata C; Alvarez, Jessica

    2016-05-01

    Our goals were to assess whether allergic rhinitis (AR) is an aggravating factor that affects the severity of sleep apnea in children with tonsils/adenoid hypertrophy (T&A) and to compare polysomnographic data from children with and without AR. This prospective study included 135 children (age range, 3 to 14 years) with sleep-disordered breathing (SDB) resulting from T&A. Children with lung, neurological, or craniofacial problems; septal deviations; previous pharyngeal surgeries; or orthodontic treatments were excluded. All children underwent a clinical evaluation, nasopharyngoscopy or lateral X-ray imaging, sleep study, and hypersensitivity skin-prick test. The mean patient age was 6.44 ± 2.55 years (83 males). AR was present in 42.2% of the children; 40% presented with sleep apnea; and 17.04% had sleep apnea and AR. The percentage of time spent in the rapid eye movement (REM) sleep stage was lower among children with AR without sleep apnea (p = 0.028); however, the percentage of REM sleep was not significantly different among children with apnea (p = 0.2922). No difference in the apnea-hypopnea index (AHI) was observed between the children with (AHI = 2.79 events/hour) and without AR (3.75 events/hour, p = 0.4427). A multivariate analysis showed that nasal congestion was an important factor that can affect the duration of the REM sleep stage. AR affects REM sleep in children with SDB without sleep apnea, and AR is not an aggravating factor regarding the severity of AHI. © 2016 ARS-AAOA, LLC.

  10. Time-of-night variations in the story-like organization of dream experience developed during rapid eye movement sleep.

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    Cipolli, Carlo; Guazzelli, Mario; Bellucci, Claudia; Mazzetti, Michela; Palagini, Laura; Rosenlicht, Nicholas; Feinberg, Irwin

    2015-04-01

    This study aimed to investigate the cycles (2nd/4th) and duration-related (5/10 min) variations in the story-like organization of dream experience elaborated during rapid eye movement (REM) sleep. Dream reports were analysed using story grammar rules. Reports were provided by those subjects (14 of 22) capable of reporting a dream after each of the four awakenings provoked in 2 consecutive nights during REM sleep of the 2nd and 4th cycles, after periods of either 5 or 10 min, counterbalanced across the nights. Two researchers who were blind as to the sleep condition scored the dream reports independently. The values of the indicators of report length (measured as value of total word count) and of story-like organization of dream reports were matched taking time-of-night (2nd and 4th cycles) and REM duration (5 versus 10 min) as factors. Two-way analyses of variance showed that report length increased significantly in 4th-cycle REM sleep and nearly significantly for longer REM duration, whereas the number of dream-stories per report did not vary. The indices of sequential (number of statements describing the event structure developed in the story) and hierarchical (number of episodes per story) organization increased significantly only in dream-stories reported after 10 min of 4th-cycle REM sleep. These findings indicate that the characteristics of structural organization of dream-stories vary along with time of night, and suggest that the elaboration of a long and complex dream-story requires a fairly long time and the availability of a great amount of cognitive resources to maintain its continuity and coherence. © 2014 European Sleep Research Society.

  11. Effect of dual tasking on postural responses to rapid lower limb movement while seated on an exercise ball.

    Science.gov (United States)

    Jones, P; Sorinola, I; Strutton, P H

    2014-06-01

    Postural adjustments are used by the central nervous system to pre-empt and correct perturbations in balance during voluntary body movements. Alteration in these responses is associated with a number of neuromuscular/musculoskeletal conditions. Attention has been identified as important in this system; performing a concurrent cognitive task has been suggested to reduce the efficacy of this postural control. The aim of this study was to examine the effect of concurrent cognitive tasking on anticipatory postural adjustments while sitting on an exercise ball with a view to help inform future rehabilitation programmes. Bilateral EMG activity was recorded from the external and internal obliques, rectus abdominis, erector spinae and the right rectus femoris of 20 healthy subjects (9 males) with mean (SD) age of 21.88 (0.86) years (range 21-24 years). A rapid hip flexion protocol was carried out under three conditions: no concurrent task, counting out loud up from one and completing a serial sevens task. The addition of the cognitive task delayed and reduced the EMG in the prime mover muscle but had little impact on the responses of the trunk muscles within the time frame of the anticipatory responses; suggestive of a decoupling of voluntary and postural control mechanisms. The results of this study suggest that perhaps the clinical effects of dual task may not be largely due to changes in anticipatory postural adjustments. However, it would be important to compare these results to those seen in older and functionally impaired individuals as this would be more representative of the typical population undertaking such rehabilitation programmes. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Prevalence of rapid eye movement sleep behavior disorder (RBD) in Parkinson's disease: a meta and meta-regression analysis.

    Science.gov (United States)

    Zhang, Xiaona; Sun, Xiaoxuan; Wang, Junhong; Tang, Liou; Xie, Anmu

    2017-01-01

    Rapid eye movement sleep behavior disorder (RBD) is thought to be one of the most frequent preceding symptoms of Parkinson's disease (PD). However, the prevalence of RBD in PD stated in the published studies is still inconsistent. We conducted a meta and meta-regression analysis in this paper to estimate the pooled prevalence. We searched the electronic databases of PubMed, ScienceDirect, EMBASE and EBSCO up to June 2016 for related articles. STATA 12.0 statistics software was used to calculate the available data from each research. The prevalence of RBD in PD patients in each study was combined to a pooled prevalence with a 95 % confidence interval (CI). Subgroup analysis and meta-regression analysis were performed to search for the causes of the heterogeneity. A total of 28 studies with 6869 PD cases were deemed eligible and included in our meta-analysis based on the inclusion and exclusion criteria. The pooled prevalence of RBD in PD was 42.3 % (95 % CI 37.4-47.1 %). In subgroup analysis and meta-regression analysis, we found that the important causes of heterogeneity were the diagnosis criteria of RBD and age of PD patients (P = 0.016, P = 0.019, respectively). The results indicate that nearly half of the PD patients are suffering from RBD. Older age and longer duration are risk factors for RBD in PD. We can use the minimal diagnosis criteria for RBD according to the International Classification of Sleep Disorders to diagnose RBD patients in our daily work if polysomnography is not necessary.

  13. Ventricular orexin-A (hypocretin-1 levels correlate with rapid-eye-movement sleep without atonia in Parkinson's disease

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    Bridoux A

    2013-06-01

    Full Text Available Agathe Bridoux,1,2 Stephane Moutereau,3 Ala Covali-Noroc,1 Laurent Margarit,1 Stephane Palfi,4 Jean-Paul Nguyen,5 Jean-Pascal Lefaucheur,1,2 Pierre Césaro,6 Marie-Pia d'Ortho,7 Xavier Drouot1,21Service de Physiologie, Groupe Henri Mondor, 2Faculté de Médecine, Université Paris Est Créteil, 3Service de Biochimie, Groupe Henri Mondor, 4UF Neurochirurgie Fonctionnelle, Groupe Henri Mondor, Créteil, France; 5Service de Neurochirurgie, Hôpital Nord Laënnec, Nantes, France; 6Service de Neurologie, Groupe Henri Mondor, Créteil, France; 7Service de Physiologie, Groupe Bichat – Claude Bernard, Paris, FranceObjective: Patients with Parkinson's disease frequently complain of sleep disturbances and loss of muscle atonia during rapid-eye-movement (REM sleep is not rare. The orexin-A (hypocretin-1 hypothalamic system plays a central role in controlling REM sleep. Loss of orexin neurons results in narcolepsy-cataplexy, a condition characterized by diurnal sleepiness and REM sleep without atonia. Alterations in the orexin-A system have been also documented in Parkinson's disease, but whether these alterations have clinical consequences remains unknown.Methods: Here, we measured orexin-A levels in ventricular cerebrospinal fluid from eight patients with Parkinson's disease (four males and four females who underwent ventriculography during deep brain-stimulation surgery and performed full-night polysomnography before surgery.Results: Our results showed a positive correlation between orexin-A levels and REM sleep without muscle atonia.Conclusion: Our results suggest that high levels of orexin-A in Parkinson's disease may be associated with loss of REM muscle atonia.Keywords: Parkinson, orexin-A, ventricular CSF, REM atonia

  14. Prognostic and symptomatic aspects of rapid eye movement sleep in a mouse model of posttraumatic stress disorder

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    Stephanie A. Polta

    2013-05-01

    Full Text Available Not every individual develops Posttraumatic Stress Disorder (PTSD after the exposure to a potentially traumatic event. Therefore, the identification of pre-existing risk factors and early diagnostic biomarkers is of high medical relevance. However, no objective biomarker has yet progressed into clinical practice. Sleep disturbances represent commonly reported complaints in PTSD patients. In particular, changes in rapid eye movement sleep (REMS properties are frequently observed in PTSD patients. Here, we examined in a mouse model of PTSD whether (1 mice developed REMS alterations after trauma and (2 whether REMS architecture before and/or shortly after trauma predicted the development of PTSD-like symptoms. We monitored sleep-wake behavior via combined EEG/EMG recordings immediately before (24 h pre, immediately after (0-48 h post and two months after exposure to an electric foot shock in male C57BL/6N mice (n=15. PTSD-like symptoms, including hyperarousal, contextual and generalized fear, were assessed one month post-trauma.Shocked mice showed early-onset and sustained elevation of REMS compared to non-shocked controls. In addition, REMS architecture before trauma was correlated with the intensity of acoustic startle responses, but not contextual fear, one month after trauma.Our data suggest REMS as prognostic (pre-trauma and symptomatic (post-trauma marker of PTSD-like symptoms in mice. Translated to the situation in humans, REMS may constitute a viable, objective and non-invasive biomarker in PTSD and other trauma-related psychiatric disorders, which could guide pharmacological interventions in humans at high risk.

  15. Study on microstructure of corpus striatum in patients with idiopathic rapid eye movement sleep behavior disorder using magnetic resonance imaging

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    Ya-meng ZHANG

    2017-07-01

    Full Text Available Objective To investigate the structure of corpus striatum and the integrity of white matter fiber in patients with Parkinson's disease (PD and idiopathic rapid eye movement sleep behavior disorder (iRBD.  Methods Twelve patients with iRBD, 12 patients with PD and 10 healthy subjects that were well matched in gender, age and education were enrolled in this study. Head MRI examination was performed to all subjects to observe the changes of corpus striatum structure (the gray matter volume and the integrity of white matter fiber [fractional anisotropy (FA] by combining voxel?based morphometry (VBM and diffusion tensor imaging (DTI.  Results Compared with healthy subjects, the gray matter volume of left caudate nucleus was significantly decreased (P < 0.005, and FA values of left caudate nucleus (P < 0.005, right caudate nucleus (P < 0.001 and right putamen (P < 0.05 were all significantly reduced in iRBD patients; FA value of right putamen was significantly decreased in PD patients (P < 0.05. Compared with PD patients, the gray matter volume of left caudate nucleus of iRBD patients was significantly reduced (P < 0.001, FA values of left caudate nucleus (P < 0.01 and right caudate nucleus (P < 0.005 of iRBD patients were significantly reduced.  Conclusions There is atrophy of gray matter volume and extensive white matter fiber impairment in corpus striatum of patients with iRBD, and the white matter fiber impairment was similar to PD, which provides an anatomical evidence for iRBD being presymptom of PD. DOI: 10.3969/j.issn.1672-6731.2017.05.008

  16. Cytomorphometric changes in the dorsal raphe neurons after rapid eye movement sleep deprivation are mediated by noradrenalin in rats

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    Biswas Sudipta

    2010-10-01

    Full Text Available Abstract Objectives This study was carried out to investigate the effect of rapid eye movement sleep (REMS deprivation (REMSD on the cytomorphology of the dorsal raphe (DR neurons and to evaluate the possible role of REMSD-induced increased noradrenalin (NA in mediating such effects. Methods Rats were REMS deprived by the flowerpot method; free moving normal home cage rats, large platform and post REMS-deprived recovered rats were used as controls. Further, to evaluate if the effects were induced by NA, separate sets of experimental rats were treated (i.p. with α1-adrenoceptor antagonist, prazosin (PRZ. Histomorphometric analysis of DR neurons in stained brain sections were performed in experimental and control rats; neurons in inferior colliculus (IC served as anatomical control. Results The mean size of DR neurons was larger in REMSD group compared to controls, whereas, neurons in the recovered group of rats did not significantly differ than those in the control animals. Further, mean cell size in the post-REMSD PRZ-treated animals was comparable to those in the control groups. IC neurons were not affected by REMSD. Conclusions REMS loss has been reported to impair several physiological, behavioral and cellular processes. The mean size of the DR neurons was larger in the REMS deprived group of rats than those in the control groups; however, in the REMS deprived and prazosin treated rats the size was comparable to the normal rats. These results showed that REMSD induced increase in DR neuronal size was mediated by NA acting on α1-adrenoceptor. The findings suggest that the sizes of DR neurons are sensitive to REMSD, which if not compensated could lead to neurodegeneration and associated disorders including memory loss and Alzheimer's disease.

  17. Probable rapid eye movement sleep behavior disorder, nocturnal disturbances and quality of life in patients with Parkinson’s disease: a case-controlled study using the rapid eye movement sleep behavior disorder screening questionnaire

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    Suzuki Keisuke

    2013-02-01

    Full Text Available Abstract Background Increasing evidence provides a clear association between rapid eye movement sleep behavior disorders (RBD and Parkinson’s disease (PD, but the clinical features that determine the co-morbidity of RBD and PD are not yet fully understood. Methods We evaluated the characteristics of nocturnal disturbances and other motor and non-motor features related to RBD in patients with PD and the impact of RBD on their quality of life. Probable RBD (pRBD was evaluated using the Japanese version of the RBD screening questionnaire (RBDSQ-J. Results A significantly higher frequency of pRBD was observed in PD patients than in the controls (RBDSQ-J ≥ 5 or ≥ 6: 29.0% vs. 8.6%; 17.2% vs. 2.2%, respectively. After excluding restless legs syndrome and snorers in the PD patients, the pRBD group (RBDSQ-J≥5 showed higher scores compared with the non-pRBD group on the Parkinson’s disease sleep scale-2 (PDSS-2 total and three-domain scores. Early morning dystonia was more frequent in the pRBD group. The Parkinson’s Disease Questionnaire (PDQ-39 domain scores for cognition and emotional well-being were higher in the patients with pRBD than in the patients without pRBD. There were no differences between these two groups with respect to the clinical subtype, disease severity or motor function. When using a cut-off of RBDSQ-J = 6, a similar trend was observed for the PDSS-2 and PDQ-39 scores. Patients with PD and pRBD had frequent sleep onset insomnia, distressing dreams and hallucinations. The stepwise linear regression analysis showed that the PDSS-2 domain “motor symptoms at night”, particularly the PDSS sub-item 6 “distressing dreams”, was the only predictor of RBDSQ-J in PD. Conclusion Our results indicate a significant impact of RBD co-morbidity on night-time disturbances and quality of life in PD, particularly on cognition and emotional well-being. RBDSQ may be a useful tool for not only screening RBD in PD patients

  18. The Clinical Phenotype of Idiopathic Rapid Eye Movement Sleep Behavior Disorder at Presentation: A Study in 203 Consecutive Patients.

    Science.gov (United States)

    Fernández-Arcos, Ana; Iranzo, Alex; Serradell, Mónica; Gaig, Carles; Santamaria, Joan

    2016-01-01

    To describe the clinical phenotype of idiopathic rapid eye movement (REM) sleep behavior disorder (IRBD) at presentation in a sleep center. Clinical history review of 203 consecutive patients with IRBD identified between 1990 and 2014. IRBD was diagnosed by clinical history plus video-polysomnographic demonstration of REM sleep with increased electromyographic activity linked to abnormal behaviors. Patients were 80% men with median age at IRBD diagnosis of 68 y (range, 50-85 y). In addition to the already known clinical picture of IRBD, other important features were apparent: 44% of the patients were not aware of their dream-enactment behaviors and 70% reported good sleep quality. In most of these cases bed partners were essential to convince patients to seek medical help. In 11% IRBD was elicited only after specific questioning when patients consulted for other reasons. Seven percent did not recall unpleasant dreams. Leaving the bed occurred occasionally in 24% of subjects in whom dementia with Lewy bodies often developed eventually. For the correct diagnosis of IRBD, video-polysomnography had to be repeated in 16% because of insufficient REM sleep or electromyographic artifacts from coexistent apneas. Some subjects with comorbid obstructive sleep apnea reported partial improvement of RBD symptoms following continuous positive airway pressure therapy. Lack of therapy with clonazepam resulted in an increased risk of sleep related injuries. Synucleinopathy was frequently diagnosed, even in patients with mild severity or uncommon IRBD presentations (e.g., patients who reported sleeping well, onset triggered by a life event, nocturnal ambulation) indicating that the development of a neurodegenerative disease is independent of the clinical presentation of IRBD. We report the largest IRBD cohort observed in a single center to date and highlight frequent features that were not reported or not sufficiently emphasized in previous publications. Physicians should be aware of

  19. Distinct associations between energy balance and the sleep characteristics slow wave sleep and rapid eye movement sleep.

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    Rutters, F; Gonnissen, H K; Hursel, R; Lemmens, S G; Martens, E A; Westerterp-Plantenga, M S

    2012-10-01

    Epidemiologically, an inverse relationship between body mass index (BMI) and sleep duration is observed. Intra-individual variance in the amount of slow wave sleep (SWS) or rapid eye movement (REM) sleep has been related to variance of metabolic and endocrine parameters, which are risk factors for the disturbance of energy balance (EB). To investigate inter-individual relationships between EB (EB= energy intake-energy expenditure∣, MJ/24 h), SWS or REM sleep, and relevant parameters in normal-weight men during two 48 h stays in the controlled environment of a respiration chamber. A total of 16 men (age 23±3.7 years, BMI 23.9±1.9 kg m(-2)) stayed in the respiration chamber twice for 48 h to assure EB. Electroencephalography was used to monitor sleep (2330-0730 hrs). Hunger and fullness were scored by visual analog scales; mood was determined by State Trait Anxiety Index-state and food reward by liking and wanting. Baseline blood and salivary samples were collected before breakfast. Subjects were fed in EB, except for the last dinner, when energy intake was ad libitum. The subjects slept on average 441.8±49 min per night, and showed high within-subject reliability for the amount of SWS and REM sleep. Linear regression analyses showed that EB was inversely related to the amount of SWS (r=-0.43, Phunger, reward, stress and orexigenic hormone concentrations were related to overeating, as well as to the amount of SWS and REM sleep, however, after inclusion of these parameters in a multiple regression, the amount of SWS and REM sleep did not add to the explained variance of EB, which suggests that due to their individual associations, these EB parameters are mediator variables. A positive EB due to overeating, was explained by a smaller amount of SWS and higher amount of REM sleep, mediated by hunger, fullness, State Trait Anxiety Index-state scores, glucose/insulin ratio, and ghrelin and cortisol concentrations.

  20. Rapid eye movement (REM sleep deprivation reduces rat frontal cortex acetylcholinesterase (EC 3.1.1.7 activity

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    Camarini R.

    1997-01-01

    Full Text Available Rapid eye movement (REM sleep deprivation induces several behavioral changes. Among these, a decrease in yawning behavior produced by low doses of cholinergic agonists is observed which indicates a change in brain cholinergic neurotransmission after REM sleep deprivation. Acetylcholinesterase (Achase controls acetylcholine (Ach availability in the synaptic cleft. Therefore, altered Achase activity may lead to a change in Ach availability at the receptor level which, in turn, may result in modification of cholinergic neurotransmission. To determine if REM sleep deprivation would change the activity of Achase, male Wistar rats, 3 months old, weighing 250-300 g, were deprived of REM sleep for 96 h by the flower-pot technique (N = 12. Two additional groups, a home-cage control (N = 6 and a large platform control (N = 6, were also used. Achase was measured in the frontal cortex using two different methods to obtain the enzyme activity. One method consisted of the obtention of total (900 g supernatant, membrane-bound (100,000 g pellet and soluble (100,000 g supernatant Achase, and the other method consisted of the obtention of a fraction (40,000 g pellet enriched in synaptic membrane-bound enzyme. In both preparations, REM sleep deprivation induced a significant decrease in rat frontal cortex Achase activity when compared to both home-cage and large platform controls. REM sleep deprivation induced a significant decrease of 16% in the membrane-bound Achase activity (nmol thiocholine formed min-1 mg protein-1 in the 100,000 g pellet enzyme preparation (home-cage group 152.1 ± 5.7, large platform group 152.7 ± 24.9 and REM sleep-deprived group 127.9 ± 13.8. There was no difference in the soluble enzyme activity. REM sleep deprivation also induced a significant decrease of 20% in the enriched synaptic membrane-bound Achase activity (home-cage group 126.4 ± 21.5, large platform group 127.8 ± 20.4, REM sleep-deprived group 102.8 ± 14.2. Our results

  1. Dissociating the contributions of slow-wave sleep and rapid eye movement sleep to emotional item and source memory.

    Science.gov (United States)

    Groch, S; Zinke, K; Wilhelm, I; Born, J

    2015-07-01

    Sleep benefits the consolidation of emotional memories, and this influence is commonly attributed to the rapid eye movement (REM) stage of sleep. However, the contributions of sleep stages to memory for an emotional episode may differ for the event per se (i.e., item memory), and the context in which it occurred (source memory). Here, we examined the effects of slow wave sleep (SWS) and REM sleep on the consolidation of emotionally negative and neutral item (picture recognition) and source memory (recall of picture-location and picture-frame color association) in humans. In Study 1, the participants (n=18) learned 48 negative and 48 neutral pictures which were presented at specific locations and preceded by colored frames that had to be associated with the picture. In a within-subject design, learning was either followed by a 3-h early-night SWS-rich or by a late-night REM sleep-rich retention interval, then retrieval was tested. Only after REM-rich sleep, and not after SWS-rich sleep, was there a significant emotional enhancement, i.e., a significantly superior retention of emotional over neutral pictures. On the other hand, after SWS-rich sleep the retention of picture-frame color associations was better than after REM-rich sleep. However, this benefit was observed only for neutral pictures; and it was completely absent for the emotional pictures. To examine whether this absent benefit reflected a suppressive effect of emotionality on associations of minor task relevance, in Study 2 we manipulated the relevance of the picture-frame color association by combining it with information about monetary reward, following otherwise comparable procedures. Here, rewarded picture-frame color associations were equally well retained over SWS-rich early sleep no matter if the frames were associated with emotional or neutral pictures. Results are consistent with the view that REM sleep favors the emotional enhancement of item memory whereas SWS appears to contribute primarily

  2. A prospective, naturalistic follow-up study of treatment outcomes with clonazepam in rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Li, Shirley Xin; Lam, Siu Ping; Zhang, Jihui; Yu, Mandy Wai Man; Chan, Joey Wing Yin; Liu, Yaping; Lam, Venny Kwai Ho; Ho, Crover Kwok Wah; Zhou, Junying; Wing, Yun Kwok

    2016-05-01

    Rapid eye movement sleep behavior disorder (RBD) is characterized by prominent dream-enacting behaviors, often resulting in sleep-related injuries. This study aimed to prospectively examine the treatment response of people with RBD treated with clonazepam, by quantitatively delineating the characteristic changes in the clinical and polysomnographic features, and to explore the factors associated with this response. Patients diagnosed with idiopathic RBD (iRBD) were consecutively recruited and invited to complete clinical and polysomnographic (PSG) assessments and self-administered questionnaires (including the modified REM Sleep Behavior Questionnaire, RBDQ-3M) before and after the initiation of treatment with clonazepam. Thirty-nine iRBD patients (male: 74.4%, mean age at diagnosis: 68.3 ± 7.8 years) were recruited with a follow-up duration of 28.8 ± 13.3 months. Clonazepam was offered as the first-line treatment (starting dose: 0.43 ± 0.16 mg, range: 0.125-1.00; dose at follow-up: 0.98 ± 0.63 mg, range: 0.125-3). Treatment response, as defined by a complete elimination of sleep-related injuries and potentially injurious behaviors to self and/or to bed partner, at follow-up was reported in 66.7% of the overall study subjects. Frequency of disturbing dreams with violent and frightening content and vigorous behavioral RBD symptoms was significantly reduced, while residual nocturnal symptoms and an increase in REM-related EMG activities were observed at follow-up. Less optimal treatment outcomes were found to be associated with the presence of comorbid obstructive sleep apnea and earlier onset of RBD. Clonazepam differentially changes dream affect and content, as well as reduces vigorous verbal and motor behaviors. Residual RBD symptoms are common, despite treatment. Other more effective alternative or adjunctive interventions are needed for better clinical management of RBD. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Considering Valproate as a Risk Factor for Rapid Exacerbation of Complex Movement Disorder in Progressed Stages of Late-Infantile CLN2 Disease.

    Science.gov (United States)

    Johannsen, Jessika; Nickel, Miriam; Schulz, Angela; Denecke, Jonas

    2016-06-01

    Neuronal ceroid lipofuscinosis type 2 (CLN2 disease, OMIM 204500) is a rare autosomal-recessive lysosomal storage disorder. It is one of the most common neurodegenerative disorders in childhood. Symptoms include epilepsy, rapid motor and language regression, dementia, visual loss, and a complex movement disorder in later stages of the disease. We report on two children with genetically confirmed late-infantile CLN2 disease who developed a severe exacerbation of their complex movement disorder leading to hyperthermia, hyper-CK-emia and decreased level of consciousness over several weeks despite different therapeutic approaches. Both patients were on long-term antiepileptic treatment with valproate and only after the withdrawal of valproate, the movement disorder disappeared and level of consciousness improved. These observations emphasize that valproate has to be considered as a possible risk factor in patients in later stages of late-infantile CLN2 disease who develop a rapidly progressive complex movement disorder. Georg Thieme Verlag KG Stuttgart · New York.

  4. The Role of Non-Rapid Eye Movement Slow-Wave Activity in Prefrontal Metabolism across Young and Middle Age Adults

    OpenAIRE

    Wilckens, K.A.; Aizenstein, H J; Nofzinger, E.A.; James, J. A.; Hasler, B.P.; Rosario-Rivera, B.L.; Franzen, P; Germain, A.; Hall, M. H.; Kupfer, D.J.; Price, J C.; Siegle, G.J.; Buysse, D. J.

    2016-01-01

    Electroencephalographic slow-wave activity (0.5���4 Hz) during non rapid-eye-movement (NREM) sleep is a marker for cortical reorganization, particularly within the prefrontal cortex. Greater slow-wave activity during sleep may promote greater waking prefrontal metabolic rate, and in turn, executive function. However, this process may be affected by age. Here we examined whether greater NREM slow-wave activity was associated with higher prefrontal metabolism during wakefulness and whether this...

  5. Recent developments in the study of rapid human movements with the kinematic theory: Applications to handwriting and signature synthesis

    OpenAIRE

    Plamondon, Réjean; O’Reilly, Christian; Galbally, Javier; Almaksour, Abdullah; Anquetil, Éric

    2014-01-01

    International audience; Human movement modeling can be of great interest for the design of pattern recognition systems relying on the understanding of the fine motor control (such as on-line handwriting recognition or signature verification) as well as for the development of intelligent systems involving in a way or another the processing of human movements. In this paper, we briefly list the different models that have been proposed in order to characterize the handwriting process and focus o...

  6. Antarctic killer whales make rapid, round-trip movements to subtropical waters: evidence for physiological maintenance migrations?

    Science.gov (United States)

    Durban, J W; Pitman, R L

    2012-04-23

    Killer whales (Orcinus orca) are important predators in high latitudes, where their ecological impact is mediated through their movements. We used satellite telemetry to provide the first evidence of migration for killer whales, characterized by fast (more than 12 km h(-1), 6.5 knots) and direct movements away from Antarctic waters by six of 12 type B killer whales tagged when foraging near the Antarctic Peninsula, including all tags transmitting for more than three weeks. Tags on five of these whales revealed consistent movements to subtropical waters (30-37° S) off Uruguay and Brazil, in surface water temperatures ranging from -1.9°C to 24.2°C; one 109 day track documented a non-stop round trip of almost 9400 km (5075 nmi) in just 42 days. Although whales travelled slower in the warmest waters, there was no obvious interruption in swim speed or direction to indicate calving or prolonged feeding. Furthermore, these movements were aseasonal, initiating over 80 days between February and April; one whale returned to within 40 km of the tagging site at the onset of the austral winter in June. We suggest that these movements may represent periodic maintenance migrations, with warmer waters allowing skin regeneration without the high cost of heat loss: a physiological constraint that may also affect other whales.

  7. Disorders of Upper Limb Movements in Ataxia-Telangiectasia.

    Directory of Open Access Journals (Sweden)

    Aasef G Shaikh

    Full Text Available Ataxia-telangiectasia is known for cerebellar degeneration, but clinical descriptions of abnormal tone, posture, and movements suggest involvement of the network between cerebellum and basal ganglia. We quantitatively assessed the nature of upper-limb movement disorders in ataxia-telangiectasia. We used a three-axis accelerometer to assess the natural history and severity of abnormal upper-limb movements in 80 ataxia-telangiectasia and 19 healthy subjects. Recordings were made during goal-directed movements of upper limb (kinetic task, while arms were outstretched (postural task, and at rest. Almost all ataxia-telangiectasia subjects (79/80 had abnormal involuntary movements, such as rhythmic oscillations (tremor, slow drifts (dystonia or athetosis, and isolated rapid movements (dystonic jerks or myoclonus. All patients with involuntary movements had both kinetic and postural tremor, while 48 (61% also had resting tremor. The tremor was present in transient episodes lasting several seconds during two-minute recording sessions of all three conditions. Percent time during which episodic tremor was present was greater for postural and kinetic tasks compared to rest. Resting tremor had higher frequency but smaller amplitude than postural and kinetic tremor. Rapid non-rhythmic movements were minimal during rest, but were triggered during sustained arm postures and goal directed arm movements suggesting they are best considered a form of dystonic jerks or action myoclonus. Advancing age did not correlate with the severity of involuntary limb movements. Abnormal upper-limb movements in ataxia-telangiectasia feature classic cerebellar impairment, but also suggest involvement of the network between the cerebellum and basal ganglia.

  8. Octopus-inspired multi-arm robotic swimming.

    Science.gov (United States)

    Sfakiotakis, M; Kazakidi, A; Tsakiris, D P

    2015-05-13

    The outstanding locomotor and manipulation characteristics of the octopus have recently inspired the development, by our group, of multi-functional robotic swimmers, featuring both manipulation and locomotion capabilities, which could be of significant engineering interest in underwater applications. During its little-studied arm-swimming behavior, as opposed to the better known jetting via the siphon, the animal appears to generate considerable propulsive thrust and rapid acceleration, predominantly employing movements of its arms. In this work, we capture the fundamental characteristics of the corresponding complex pattern of arm motion by a sculling profile, involving a fast power stroke and a slow recovery stroke. We investigate the propulsive capabilities of a multi-arm robotic system under various swimming gaits, namely patterns of arm coordination, which achieve the generation of forward, as well as backward, propulsion and turning. A lumped-element model of the robotic swimmer, which considers arm compliance and the interaction with the aquatic environment, was used to study the characteristics of these gaits, the effect of various kinematic parameters on propulsion, and the generation of complex trajectories. This investigation focuses on relatively high-stiffness arms. Experiments employing a compliant-body robotic prototype swimmer with eight compliant arms, all made of polyurethane, inside a water tank, successfully demonstrated this novel mode of underwater propulsion. Speeds of up to 0.26 body lengths per second (approximately 100 mm s(-1)), and propulsive forces of up to 3.5 N were achieved, with a non-dimensional cost of transport of 1.42 with all eight arms and of 0.9 with only two active arms. The experiments confirmed the computational results and verified the multi-arm maneuverability and simultaneous object grasping capability of such systems.

  9. A microstructural study of sleep instability in drug-naive patients with schizophrenia and healthy controls: sleep spindles, rapid eye movements, and muscle atonia.

    Science.gov (United States)

    Guénolé, Fabian; Chevrier, Elyse; Stip, Emmanuel; Godbout, Roger

    2014-05-01

    This study aimed at characterizing the functional stability of sleep in schizophrenia by quantifying dissociated stages of sleep (DSS), and to explore their correlation with psychopathology. The sleep of 10 first-break, drug-naive young adults with schizophrenia and 10 controls was recorded. Four basic DSS patterns were scored: 1) the transitional EEG-mixed intermediate stage (EMIS); 2) Rapid-eye-movement (REM) sleep without rapid eye movement (RSWR); 3) REM sleep without atonia (RSWA); and 4) non-REM sleep with rapid eye movements. An intermediate sleep (IS) score was calculated by summing EMIS and RSWR scores, and the durations of intra-REM sleep periods IS (IRSPIS) and IS scored "at the expense" of REM sleep (ISERS) were determined. Patients were administered the Brief Psychiatric Rating Scale (BPRS) at the time of recording. Proportions of each DSS variables over total sleep time and proportions of IRSPIS and ISERS over REM sleep duration were compared between patients and controls. Correlation coefficients between DSS variables and BPRS total scores were calculated. The proportion of total DSS did not differ between patients and controls. Among DSS subtypes, RSWA was significantly increased in patients while other comparisons showed no significant differences. Significant positive correlations were found between BPRS scores and proportions of DSS, IS, RSWR, IRSPIS and ISERS over total sleep and REM sleep durations. These results demonstrate the functional instability of REM sleep in first-break, drug naive young adults with schizophrenia and unveil a pattern reminiscent of REM sleep behavior disorder. The significant correlation suggests that schizophrenia and REM sleep share common neuronal control mechanisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Cognitive performances and mild cognitive impairment in idiopathic rapid eye movement sleep behavior disorder: results of a longitudinal follow-up study.

    Science.gov (United States)

    Terzaghi, Michele; Zucchella, Chiara; Rustioni, Valter; Sinforiani, Elena; Manni, Raffaele

    2013-10-01

    To investigate the capacity of neuropsychological deficits in idiopathic rapid eye movement sleep behavior disorder (iRBD) to predict the development of dementia and/or parkinsonism. Prospective longitudinal follow-up study. Tertiary sleep center. Twenty patients with initial iRBD (19 males, mean age 66.1 ± 7.1) underwent a clinical and neuropsychological follow-up within a mean of 43 ± 19 months. Neuropsychological performances at baseline were compared with those of healthy controls matched for sex, age, and education. Discontinuation of clonazepam at least 7 days before the follow-up evaluation. At follow-up, the Wilcoxon test showed a significant worsening of scores on Raven Colored Matrices 47 (P = 0.01), Attentive matrices (P = 0.002), phonemic (P = 0.04) and sematic (P = 0.04) fluency. Thirteen patients (65%) showed cognitive deterioration involving multiple domains. Of these, four patients (20%) maintained a stable cognitive dysfunction and nine (45%) showed a progression of cognitive dysfunction: six (30%) in constructional abilities (P = 0.03), four (20%) in short-term memory (P = NS), three (15%) in executive functions and non-verbal logic (P = NS), one (5%) in verbal fluency (P = NS), and one (5%) in long-term memory (P = NS) (McNemar test). Seven patients (35%) retained a normal cognitive profile. Mild cognitive impairment (MCI) was diagnosed at baseline in seven patients (35%). At follow-up, three of these patients showed overt dementia that was accompanied by parkinsonism in all cases; one had worsened from non-amnesic single-domain to nonamnesic multiple-domain MCI, two were stable, and one patient no longer met the criteria for MCI. Four patients (20%) without MCI at baseline had MCI at follow-up. Patients who developed MCI/dementia had an older age at disease onset (65.8 ± 5.4 versus 56.8 ± 9.3; P = 0.01) compared with those who did not. Our findings corroborate evidence that visuospatial abilities constitute the area most affected in

  11. Rapid movement of frozen debris-lobes: implications for permafrost degradation and slope instability in the south-central Brooks Range, Alaska

    Directory of Open Access Journals (Sweden)

    R. P. Daanen

    2012-05-01

    Full Text Available We present the results of a reconnaissance investigation of unusual debris mass-movement features on permafrost slopes that pose a potential infrastructure hazard in the south-central Brooks Range, Alaska. For the purpose of this paper, we describe these features as frozen debris-lobes. We focus on the characterisation of frozen debris-lobes as indicators of various movement processes using ground-based surveys, remote sensing, field and laboratory measurements, and time-lapse observations of frozen debris-lobe systems along the Dalton Highway. Currently, some frozen debris-lobes exceed 100 m in width, 20 m in height and 1000 m in length. Our results indicate that frozen debris-lobes have responded to climate change by becoming increasingly active during the last decades, resulting in rapid downslope movement. Movement indicators observed in the field include toppling trees, slumps and scarps, detachment slides, striation marks on frozen sediment slabs, recently buried trees and other vegetation, mudflows, and large cracks in the lobe surface. The type and diversity of observed indicators suggest that the lobes likely consist of a frozen debris core, are subject to creep, and seasonally unfrozen surface sediment is transported in warm seasons by creep, slumping, viscous flow, blockfall and leaching of fines, and in cold seasons by creep and sliding of frozen sediment slabs. Ground-based measurements on one frozen debris-lobe over three years (2008–2010 revealed average movement rates of approximately 1 cm day−1, which is substantially larger than rates measured in historic aerial photography from the 1950s to 1980s. We discuss how climate change may further influence frozen debris-lobe dynamics, potentially accelerating their movement. We highlight the potential direct hazard that one of the studied frozen debris-lobes may pose in the coming years and decades to the nearby Trans Alaska Pipeline System and the Dalton Highway, the

  12. Bionic robot arm with compliant actuators

    Science.gov (United States)

    Moehl, Bernhard

    2000-10-01

    Traditional robotics uses non-compliant materials for all components involved in the production of movement. Elasticity is avoided as far as possible, because it leads to hazardous oscillations and makes control of precise movements very difficult. Due to this deliberate stiffness, robots are typically heavy and clumsy structures in comparison to their living counterparts (i.e. man and animals). Yet, moving systems in nature cope not only with the difficulties introduced by compliant materials, they also take advantage of the elasticity in muscles and tendons to produce smooth and even rapid movements. It is understood, that elasticity in a multi-jointed moving system requires sophisticated control mechanisms- as provided by a nervous system or a suitably programmed computer. In this contribution I shall describe a two-jointed robot with purpose-built elasticity in its actuators. This is accomplished by spiral springs places in series with a conventional electric motor and a tendon to the arm. It is shown that, with sufficiently soft elasticity, oscillations can be avoided by active oscillation damping. (Such active oscillation damping presumably also governs movement control in man and animals.) Furthermore, once the major problem has been overcome, elasticity is found to offer a wide spectrum of valuable advantages, as far as the most serious problems in traditional robotics are concerned. They are summarized by terms such as less dangerous, position tolerant, lightweight construction, controlled forces, and ballistic movements. These will be explained in detail and presented for discussion.

  13. Coilin is rapidly recruited to UVA-induced DNA lesions and γ-radiation affects localized movement of Cajal bodies.

    Science.gov (United States)

    Bártová, Eva; Foltánková, Veronika; Legartová, Soňa; Sehnalová, Petra; Sorokin, Dmitry V; Suchánková, Jana; Kozubek, Stanislav

    2014-01-01

    Cajal bodies are important nuclear structures containing proteins that preferentially regulate RNA-related metabolism. We investigated the cell-type specific nuclear distribution of Cajal bodies and the level of coilin, a protein of Cajal bodies, in non-irradiated and irradiated human tumor cell lines and embryonic stem (ES) cells. Cajal bodies were localized in different nuclear compartments, including DAPI-poor regions, in the proximity of chromocenters, and adjacent to nucleoli. The number of Cajal bodies per nucleus was cell cycle-dependent, with higher numbers occurring during G2 phase. Human ES cells contained a high coilin level in the nucleoplasm, but coilin-positive Cajal bodies were also identified in nuclei of mouse and human ES cells. Coilin, but not SMN, recognized UVA-induced DNA lesions, which was cell cycle-independent. Treatment with γ-radiation reduced the localized movement of Cajal bodies in many cell types and GFP-coilin fluorescence recovery after photobleaching was very fast in nucleoplasm in comparison with GFP-coilin recovery in DNA lesions. By contrast, nucleolus-localized coilin displayed very slow fluorescence recovery after photobleaching, which indicates very slow rates of protein diffusion, especially in nucleoli of mouse ES cells.

  14. Can observers link dream content to behaviours in rapid eye movement sleep behaviour disorder? A cross-sectional experimental pilot study.

    Science.gov (United States)

    Valli, Katja; Frauscher, Birgit; Gschliesser, Viola; Wolf, Elisabeth; Falkenstetter, Tina; Schönwald, Suzana V; Ehrmann, Laura; Zangerl, Anja; Marti, Isabelle; Boesch, Sylvia M; Revonsuo, Antti; Poewe, Werner; Högl, Birgit

    2012-02-01

    Motor activity in rapid eye movement (REM) sleep behaviour disorder (RBD) has been linked to dream content. Systematic and controlled sleep laboratory studies directly assessing the relation between RBD behaviours and experienced dream content are, however, largely lacking. We aimed to investigate whether a link can be established between RBD behaviours and dream content when both are systematically sampled in a controlled setting. We investigated six patients with Parkinson syndrome and RBD who underwent 2-3 nights of video-polysomnographic recording during which they were awakened from REM sleep (10 min after the onset of the second and successive REM periods). Spontaneous free-worded dream reports and a structured dream questionnaire were obtained. Video recordings of motor manifestations were each combined with four dream reports, and seven judges had to match the video clip with the correctly reported dream content from a choice of four possibilities. Of the 35 REM sleep awakenings performed, a total of 17 (48.6%) motor-behavioural episodes with recalled dream content were obtained. The mean of correctly identified video-dream pairs was 39.5% (range 0-100%). Our data showed that reported dream content can be linked to motor behaviours above chance level. Matching accuracy was affected mainly by the clarity of dream reports and the specific nature of movements manifest in video recordings. © 2011 European Sleep Research Society.

  15. Decreased phasic EMG activity during rapid eye movement sleep in treatment-naïve Parkinson's disease: effects of treatment with levodopa and progression of illness.

    Science.gov (United States)

    Garcia-Borreguero, Diego; Caminero, Ana B; De La Llave, Yolanda; Larrosa, Oscar; Barrio, Soledad; Granizo, Juan J; Pareja, Juan A

    2002-09-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is frequently associated with Parkinson's disease (PD) and may anticipate its diagnosis by several years. We assessed the presence of motor dyscontrol during REM sleep in treatment-naïve PD patients and investigated the putative effect of levodopa (L-dopa) treatment on motor activity. Overnight sleep studies were performed on 15 previously untreated PD patients and 14 controls at baseline, again after a 3- to 9-month treatment period with a low dose of L-dopa, and 2 to 5 days after treatment discontinuation (in 8 patients). No differences in sleep parameters were observed across groups or treatment conditions. None of the patients met criteria for RBD at baseline, whereas 5 patients were symptomatic at the time of the second sleep study. A quantitative analysis of electromyographic (EMG) activity during REM sleep showed a lower phasic twitching activity in untreated PD than in controls. However, an increase in both phasic twitching and tonic activity was found after treatment with L-dopa. Discontinuation of treatment resulted in a return to pretreatment values of phasic but not of tonic EMG activity. Thus, the increase in phasic activity seems to depend on the effects of L-dopa, whereas the increase in tonic EMG activity during REM sleep might be caused by other factors such as the progression of disease. Potential implications for the understanding of the relationship between RBD and PD are discussed. Copyright 2002 Movement Disorder Society

  16. The Benefit of Directed Forgetting Persists After a Daytime Nap: The Role of Spindles and Rapid Eye Movement Sleep in the Consolidation of Relevant Memories.

    Science.gov (United States)

    Blaskovich, Borbála; Szollosi, Ágnes; Gombos, Ferenc; Racsmány, Mihály; Simor, Péter

    2017-03-01

    We aimed to investigate the effect of directed forgetting instruction on memory retention after a 2-hour delay involving a daytime nap or an equivalent amount of time spent awake. We examined the associations between sleep-specific oscillations and the retention of relevant and irrelevant study materials. We applied a list-method directed forgetting paradigm manipulating the perceived relevance of previously encoded lists of words. Participants were randomly assigned to either a nap or an awake group, and to a remember or a forget subgroup. The remember and the forget subgroups were both instructed to study two consecutive lists of words, although, the forget subgroup was manipulated to forget the first list and memorize only the second one. Participants were 112 healthy individuals (44 men; Mage = 21.4 years, SD = 2.4). A significant directed forgetting effect emerged after a 2-hour delay both in the awake and sleep conditions; however, the effect was more pronounced within the sleep group. The benefit of directed forgetting, that is, relatively enhanced recall of relevant words in the forget group, was evidenced only in those participants that reached rapid eye movement (REM) phase. Non-rapid eye movement (NREM) sigma power was correlated with memory performance for the relevant (second) list, and sleep spindle amplitude was associated with the retention of both lists. These associations, however, were detected only within the forget subgroup. REM duration correlated with recall performance for the relevant (second) list within the forget subgroup, and with recall performance for the first list within the remember subgroup. A directed forgetting effect persists after a 2-hour delay spent awake or asleep. Spindle-related activity and subsequent REM sleep might selectively facilitate the processing of memories that are considered to be relevant for the future.

  17. Control of the strength of visual-motor transmission as the mechanism of rapid adaptation of priors for Bayesian inference in smooth pursuit eye movements.

    Science.gov (United States)

    Darlington, Timothy R; Tokiyama, Stefanie; Lisberger, Stephen G

    2017-08-01

    Bayesian inference provides a cogent account of how the brain combines sensory information with "priors" based on past experience to guide many behaviors, including smooth pursuit eye movements. We now demonstrate very rapid adaptation of the pursuit system's priors for target direction and speed. We go on to leverage that adaptation to outline possible neural mechanisms that could cause pursuit to show features consistent with Bayesian inference. Adaptation of the prior causes changes in the eye speed and direction at the initiation of pursuit. The adaptation appears after a single trial and accumulates over repeated exposure to a given history of target speeds and directions. The influence of the priors depends on the reliability of visual motion signals: priors are more effective against the visual motion signals provided by low-contrast vs. high-contrast targets. Adaptation of the direction prior generalizes to eye speed and vice versa, suggesting that both priors could be controlled by a single neural mechanism. We conclude that the pursuit system can learn the statistics of visual motion rapidly and use those statistics to guide future behavior. Furthermore, a model that adjusts the gain of visual-motor transmission predicts the effects of recent experience on pursuit direction and speed, as well as the specifics of the generalization between the priors for speed and direction. We suggest that Bayesian inference in pursuit behavior is implemented by distinctly non-Bayesian internal mechanisms that use the smooth eye movement region of the frontal eye fields to control of the gain of visual-motor transmission.NEW & NOTEWORTHY Bayesian inference can account for the interaction between sensory data and past experience in many behaviors. Here, we show, using smooth pursuit eye movements, that the priors based on past experience can be adapted over a very short time frame. We also show that a single model based on direction-specific adaptation of the strength of

  18. Effectiveness of Eye Movement Desensitization and Reprocessing in German Armed Forces Soldiers With Post-Traumatic Stress Disorder Under Routine Inpatient Care Conditions.

    Science.gov (United States)

    Köhler, Kai; Eggert, Patrick; Lorenz, Sebastian; Herr, Kerstin; Willmund, Gerd; Zimmermann, Peter; Alliger-Horn, Christina

    2017-05-01

    Post-traumatic stress disorder (PTSD) is one of the more commonly occurring mental disorders following potentially traumatizing events soldiers may encounter when deployed abroad. One of the first-line recommended treatment options is eye movement desensitization and reprocessing (EMDR). The number of studies assessing the effectiveness of EMDR in German soldiers under routine conditions is currently almost nil. A retrospective, quasi-experimental effectiveness study on EMDR in an inpatient setting is presented using a prepost design. The study compares symptom reduction in soldiers (N = 78) with a wait-list (N = 18). Effect sizes of EMDR were measured for PTSD, symptoms of depression, and general mental health. Effect size for EMDR treatment of PTSD was d = 0.77; 95% confidence interval (CI): 0.51 to 1.36, for symptoms of depression d = 0.99; 95% CI: 0.31 to 1.36, and for general psychiatric symptoms d = 0.53; 95% CI: 0.17 to 1.21. The effects resulting from EMDR treatment were somewhat weaker than those reported in comparable studies in civilians. EMDR therapy is an effective treatment to reduce symptoms of PTSD and depression. However, in the military context it needs to be complemented by treatment options that specifically address further conditions perpetuating the disorders. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  19. The King-Devick (K-D) test of rapid eye movements: a bedside correlate of disability and quality of life in MS.

    Science.gov (United States)

    Moster, Stephen; Wilson, James A; Galetta, Steven L; Balcer, Laura J

    2014-08-15

    We investigated the King-Devick (K-D) test of rapid number naming as a visual performance measure in a cohort of patients with multiple sclerosis (MS). In this cross-sectional study, 81 patients with MS and 20 disease-free controls from an ongoing study of visual outcomes underwent K-D testing. A test of rapid number naming, K-D requires saccadic eye movements as well as intact vision, attention and concentration. To perform the K-D test, participants are asked to read numbers aloud as quickly as possible from three test cards; the sum of the three test card times in seconds constitutes the summary score. High-contrast visual acuity (VA), low-contrast letter acuity (1.25% and 2.5% levels), retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT), MS Functional Composite (MSFC) and vision-specific quality of life (QOL) measures (25-Item NEI Visual Functioning Questionnaire [NEI-VFQ-25] and 10-Item Neuro-Ophthalmic Supplement) were also assessed. K-D time scores in the MS cohort (total time to read the three test cards) were significantly higher (worse) compared to those for disease-free controls (P=0.003, linear regression, accounting for age). Within the MS cohort, higher K-D scores were associated with worse scores for the NEI-VFQ-25 composite (Pdisability status as disabled (receiving disability pension) did worse on K-D testing compared to those working full-time (P=0.001, accounting for age). The K-D test, a impairment, and reduced vision-specific QOL in patients with MS. Scores reflect work disability as well as structural changes as measured by OCT imaging. History of ON and abnormal binocular acuities were associated with worse K-D scores, suggesting that abnormalities detected by K-D may go along with afferent dysfunction in MS patients. A brief test that requires saccadic eye movements, K-D should be considered for future MS trials as a rapid visual performance measure. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. 49 CFR 234.255 - Gate arm and gate mechanism.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Gate arm and gate mechanism. 234.255 Section 234... Maintenance, Inspection, and Testing Inspections and Tests § 234.255 Gate arm and gate mechanism. (a) Each gate arm and gate mechanism shall be inspected at least once each month. (b) Gate arm movement shall be...

  1. Trunk Muscle Activation at the Initiation and Braking of Bilateral Shoulder Flexion Movements of Different Amplitudes.

    Directory of Open Access Journals (Sweden)

    M Eriksson Crommert

    Full Text Available The aim of this study was to investigate if trunk muscle activation patterns during rapid bilateral shoulder flexions are affected by movement amplitude. Eleven healthy males performed shoulder flexion movements starting from a position with arms along sides (0° to either 45°, 90° or 180°. EMG was measured bilaterally from transversus abdominis (TrA, obliquus internus (OI with intra-muscular electrodes, and from rectus abdominis (RA, erector spinae (ES and deltoideus with surface electrodes. 3D kinematics was recorded and inverse dynamics was used to calculate the reactive linear forces and torque about the shoulders and the linear and angular impulses. The sequencing of trunk muscle onsets at the initiation of arm movements was the same across movement amplitudes with ES as the first muscle activated, followed by TrA, RA and OI. All arm movements induced a flexion angular impulse about the shoulders during acceleration that was reversed during deceleration. Increased movement amplitude led to shortened onset latencies of the abdominal muscles and increased level of activation in TrA and ES. The activation magnitude of TrA was similar in acceleration and deceleration where the other muscles were specific to acceleration or deceleration. The findings show that arm movements need to be standardized when used as a method to evaluate trunk muscle activation patterns and that inclusion of the deceleration of the arms in the analysis allow the study of the relationship between trunk muscle activation and direction of perturbing torque during one and the same arm movement.

  2. Broken Arm

    Science.gov (United States)

    ... can cause arthritis there years later. Stiffness. The immobilization required to heal a fracture in the upper ... if you notice numbness or circulation problems. Compartment syndrome. Excessive swelling of the injured arm can cut ...

  3. Quantitative assessment of isolated rapid eye movement (REM) sleep without atonia without clinical REM sleep behavior disorder: clinical and research implications.

    Science.gov (United States)

    Sasai-Sakuma, Taeko; Frauscher, Birgit; Mitterling, Thomas; Ehrmann, Laura; Gabelia, David; Brandauer, Elisabeth; Inoue, Yuichi; Poewe, Werner; Högl, Birgit

    2014-09-01

    Rapid eye movement (REM) sleep without atonia (RWA) is observed in some patients without a clinical history of REM sleep behavior disorder (RBD). It remains unknown whether these patients meet the refined quantitative electromyographic (EMG) criteria supporting a clinical RBD diagnosis. We quantitatively evaluated EMG activity and investigated its overnight distribution in patients with isolated qualitative RWA. Fifty participants with an incidental polysomnographic finding of RWA (isolated qualitative RWA) were included. Tonic, phasic, and 'any' EMG activity during REM sleep on PSG were quantified retrospectively. Referring to the quantitative cut-off values for a polysomnographic diagnosis of RBD, 7/50 (14%) and 6/50 (12%) of the patients showed phasic and 'any' EMG activity in the mentalis muscle above the respective cut-off values. No patient was above the cut-off value for tonic EMG activity or phasic EMG activity in the anterior tibialis muscles. Patients with RWA above the cut-off value showed higher amounts of RWA during later REM sleep periods. This is the first study showing that some subjects with incidental RWA meet the refined quantitative EMG criteria for a diagnosis of RBD. Future longitudinal studies must investigate whether this subgroup with isolated qualitative RWA is at an increased risk of developing fully expressed RBD and/or neurodegenerative disease. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Essential roles of GABA transporter-1 in controlling rapid eye movement sleep and in increased slow wave activity after sleep deprivation.

    Directory of Open Access Journals (Sweden)

    Xin-Hong Xu

    Full Text Available GABA is the major inhibitory neurotransmitter in the mammalian central nervous system that has been strongly implicated in the regulation of sleep. GABA transporter subtype 1 (GAT1 constructs high affinity reuptake sites for GABA and regulates GABAergic transmission in the brain. However, the role of GAT1 in sleep-wake regulation remains elusive. In the current study, we characterized the spontaneous sleep-wake cycle and responses to sleep deprivation in GAT1 knock-out (KO mice. GAT1 KO mice exhibited dominant theta-activity and a remarkable reduction of EEG power in low frequencies across all vigilance stages. Under baseline conditions, spontaneous rapid eye movement (REM sleep of KO mice was elevated both during the light and dark periods, and non-REM (NREM sleep was reduced during the light period only. KO mice also showed more state transitions from NREM to REM sleep and from REM sleep to wakefulness, as well as more number of REM and NREM sleep bouts than WT mice. During the dark period, KO mice exhibited more REM sleep bouts only. Six hours of sleep deprivation induced rebound increases in NREM and REM sleep in both genotypes. However, slow wave activity, the intensity component of NREM sleep was briefly elevated in WT mice but remained completely unchanged in KO mice, compared with their respective baselines. These results indicate that GAT1 plays a critical role in the regulation of REM sleep and homeostasis of NREM sleep.

  5. Effects of oral temazepam on slow waves during non-rapid eye movement sleep in healthy young adults: A high-density EEG investigation.

    Science.gov (United States)

    Plante, D T; Goldstein, M R; Cook, J D; Smith, R; Riedner, B A; Rumble, M E; Jelenchick, L; Roth, A; Tononi, G; Benca, R M; Peterson, M J

    2016-03-01

    Slow waves are characteristic waveforms that occur during non-rapid eye movement (NREM) sleep that play an integral role in sleep quality and brain plasticity. Benzodiazepines are commonly used medications that alter slow waves, however, their effects may depend on the time of night and measure used to characterize slow waves. Prior investigations have utilized minimal scalp derivations to evaluate the effects of benzodiazepines on slow waves, and thus the topography of changes to slow waves induced by benzodiazepines has yet to be fully elucidated. This study used high-density electroencephalography (hdEEG) to evaluate the effects of oral temazepam on slow wave activity, incidence, and morphology during NREM sleep in 18 healthy adults relative to placebo. Temazepam was associated with significant decreases in slow wave activity and incidence, which were most prominent in the latter portions of the sleep period. However, temazepam was also associated with a decrease in the magnitude of high-amplitude slow waves and their slopes in the first NREM sleep episode, which was most prominent in frontal derivations. These findings suggest that benzodiazepines produce changes in slow waves throughout the night that vary depending on cortical topography and measures used to characterize slow waves. Further research that explores the relationships between benzodiazepine-induced changes to slow waves and the functional effects of these waveforms is indicated. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. β oscillation during slow wave sleep and rapid eye movement sleep in the electroencephalogram of a transgenic mouse model of Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Yannick Jeantet

    Full Text Available STUDY OBJECTIVES: To search for early abnormalities in electroencephalogram (EEG during sleep which may precede motor symptoms in a transgenic mouse model of hereditary neurodegenerative Huntington's disease (HD. DESIGN: In the R6/1 transgenic mouse model of HD, rhythmic brain activity in EEG recordings was monitored longitudinally and across vigilance states through the onset and progression of disease. MEASUREMENTS AND RESULTS: Mice with chronic electrode implants were recorded monthly over wake-sleep cycles (4 hours, beginning at 9-11 weeks (presymptomatic period through 6-7 months (symptomatic period. Recording data revealed a unique β rhythm (20-35 Hz, present only in R6/1 transgenic mice, which evolves in close parallel with the disease. In addition, there was an unusual relationship between this β oscillation and vigilance states: while nearly absent during the active waking state, the β oscillation appeared with drowsiness and during slow wave sleep (SWS and, interestingly, strengthened rather than dissipating when the brain returned to an activated state during rapid eye movement (REM sleep. CONCLUSIONS: In addition to providing a new in vivo biomarker and insight into Huntington's disease pathophysiology, this serendipitous observation opens a window onto the rarely explored neurophysiology of the cortico-basal ganglia circuit during SWS and REM sleep.

  7. β oscillation during slow wave sleep and rapid eye movement sleep in the electroencephalogram of a transgenic mouse model of Huntington's disease.

    Science.gov (United States)

    Jeantet, Yannick; Cayzac, Sebastien; Cho, Yoon H

    2013-01-01

    To search for early abnormalities in electroencephalogram (EEG) during sleep which may precede motor symptoms in a transgenic mouse model of hereditary neurodegenerative Huntington's disease (HD). In the R6/1 transgenic mouse model of HD, rhythmic brain activity in EEG recordings was monitored longitudinally and across vigilance states through the onset and progression of disease. Mice with chronic electrode implants were recorded monthly over wake-sleep cycles (4 hours), beginning at 9-11 weeks (presymptomatic period) through 6-7 months (symptomatic period). Recording data revealed a unique β rhythm (20-35 Hz), present only in R6/1 transgenic mice, which evolves in close parallel with the disease. In addition, there was an unusual relationship between this β oscillation and vigilance states: while nearly absent during the active waking state, the β oscillation appeared with drowsiness and during slow wave sleep (SWS) and, interestingly, strengthened rather than dissipating when the brain returned to an activated state during rapid eye movement (REM) sleep. In addition to providing a new in vivo biomarker and insight into Huntington's disease pathophysiology, this serendipitous observation opens a window onto the rarely explored neurophysiology of the cortico-basal ganglia circuit during SWS and REM sleep.

  8. Expression of prion protein in the cerebrospinal fluid of patients with Parkinson's disease complicated with rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Zhang, W J; Shang, X L; Peng, J; Zhou, M H; Sun, W J

    2017-01-23

    Parkinson's disease (PD) is one of the most common neurodegenerative diseases and mainly manifests with decreasing numbers of dopaminergic neurons. Rapid eye movement (REM) sleep behavior disorder (RBD) has an incidence of 15-47% in all PD patients. Prion proteins (PrPs), which are expressed in both neurons and glial cells of the brain, are believed to be correlated with abnormal neurological functions, although their role in PD-related sleeping disorders remains unclear. We therefore investigated the expressional profiles of PrP in PD patients with RBD. Quantitative real-time polymerase chain reaction and western blotting were used to detect the mRNA and protein levels of PrP, respectively, in the cerebrospinal fluid (CSF) of PD patients with RBD, PD patients without sleeping disorder, and healthy people (N = 23 each). We investigated the correlation between the CSF PrP level and sleeping behavior in PD patients. Patients with PD complicated with RBD had significantly elevated CSF PrP expression levels (both mRNA and protein) compared with either PD patients without sleeping disorder or healthy individuals (P < 0.05 in both cases). There is elevated expression of PrP in the CSF of PD patients with RBD. This may benefit the diagnosis of PD-related RBD.

  9. [Effect of rapid eye movement sleep deprivation on anxiety behavior and hippocampus NO level: different responses of adolescent and adult C57BL/6J mice].

    Science.gov (United States)

    Huang, Xin-Yan; Chen, Tian-Bin; Hao, Yan-Li; Zhang, Bin

    2015-10-01

    To explore the difference between adolescent and adult C57BL/6J mice in response to rapid eye movement sleep (REMS) deprivation in terms of anxiety behavior and hippocampal NO level. Both adolescent and adult C57BL/6J mice were divided into normal control (NC) group, wide platform (WP) group, and 24-hour REMS deprivation group, each group consisting of 15 mice. REMS deprivation models were established using a small platform in water tank, and the elevated plus maze test was used to examine anxiety behavior of the mice. After behavioral tests, the mice were sacrificed to examine hippocampal NO levels using enzyme-linked immunosorbent assay, and hippocampal nNOS protein expression was detected with Western blotting. The adolescent C57BL/6J mice showed no obvious differences in anxiety behaviors between the 3 groups, but NO level and nNOS expression in the hippocampus was significantly higher in REMSD group than in NC and WP groups (Pdeprivation produces different effects on anxiety-related behaviors between adolescent and adult mice possibly in relation to their different responses in terms of NO levels and nNOS expression in the hippocampus.

  10. State-specific effects of sevoflurane anesthesia on sleep homeostasis: selective recovery of slow wave but not rapid eye movement sleep.

    Science.gov (United States)

    Pal, Dinesh; Lipinski, William J; Walker, Amanda J; Turner, Ashley M; Mashour, George A

    2011-02-01

    Prolonged propofol administration does not result in signs of sleep deprivation, and propofol anesthesia appears to satisfy the homeostatic need for both rapid eye movement (REM) and non-REM (NREM) sleep. In the current study, the effects of sevoflurane on recovery from total sleep deprivation were investigated. Ten male rats were instrumented for electrophysiologic recordings under three conditions: (1) 36-h ad libitum sleep; (2) 12-h sleep deprivation followed by 24-h ad libitum sleep; and (3) 12-h sleep deprivation, followed by 6-h sevoflurane exposure, followed by 18-h ad libitum sleep. The percentage of waking, NREM sleep, and REM sleep, as well as NREM sleep δ power, were calculated and compared for all three conditions. Total sleep deprivation resulted in significantly increased NREM and REM sleep for 12-h postdeprivation. Sevoflurane exposure after deprivation eliminated the homeostatic increase in NREM sleep and produced a significant decrease in the NREM sleep δ power during the postanesthetic period, indicating a complete recovery from the effects of deprivation. However, sevoflurane did not affect the time course of REM sleep recovery, which required 12 h after deprivation and anesthetic exposure. Unlike propofol, sevoflurane anesthesia has differential effects on NREM and REM sleep homeostasis. These data confirm the previous hypothesis that inhalational agents do not satisfy the homeostatic need for REM sleep, and that the relationship between sleep and anesthesia is likely to be agent and state specific.

  11. The role of non-rapid eye movement slow-wave activity in prefrontal metabolism across young and middle-aged adults.

    Science.gov (United States)

    Wilckens, Kristine A; Aizenstein, Howard J; Nofzinger, Eric A; James, Jeffrey A; Hasler, Brant P; Rosario-Rivera, Bedda L; Franzen, Peter L; Germain, Anne; Hall, Martica H; Kupfer, David J; Price, Julie C; Siegle, Greg J; Buysse, Daniel J

    2016-06-01

    Electroencephalographic slow-wave activity (0.5-4 Hz) during non-rapid eye movement (NREM) sleep is a marker for cortical reorganization, particularly within the prefrontal cortex. Greater slow wave activity during sleep may promote greater waking prefrontal metabolic rate and, in turn, executive function. However, this process may be affected by age. Here we examined whether greater NREM slow wave activity was associated with higher prefrontal metabolism during wakefulness and whether this relationship interacted with age. Fifty-two participants aged 25-61 years were enrolled into studies that included polysomnography and a (18) [F]-fluoro-deoxy-glucose positron emission tomography scan during wakefulness. Absolute and relative measures of NREM slow wave activity were assessed. Semiquantitative and relative measures of cerebral metabolism were collected to assess whole brain and regional metabolism, focusing on two regions of interest: the dorsolateral prefrontal cortex and the orbitofrontal cortex. Greater relative slow wave activity was associated with greater dorsolateral prefrontal metabolism. Age and slow wave activity interacted significantly in predicting semiquantitative whole brain metabolism and outside regions of interest in the posterior cingulate, middle temporal gyrus and the medial frontal gyrus, such that greater slow-wave activity was associated with lower metabolism in the younger participants and greater metabolism in the older participants. These results suggest that slow-wave activity is associated with cerebral metabolism during wakefulness across the adult lifespan within regions important for executive function. © 2016 European Sleep Research Society.

  12. Promotion of non-rapid eye movement sleep and activation of reticular thalamic neurons by a novel MT2 melatonin receptor ligand.

    Science.gov (United States)

    Ochoa-Sanchez, Rafael; Comai, Stefano; Lacoste, Baptiste; Bambico, Francis Rodriguez; Dominguez-Lopez, Sergio; Spadoni, Gilberto; Rivara, Silvia; Bedini, Annalida; Angeloni, Debora; Fraschini, Franco; Mor, Marco; Tarzia, Giorgio; Descarries, Laurent; Gobbi, Gabriella

    2011-12-14

    Melatonin activates two brain G-protein coupled receptors, MT(1) and MT(2), whose differential roles in the sleep-wake cycle remain to be defined. The novel MT(2) receptor partial agonist, N-{2-[(3-methoxyphenyl) phenylamino] ethyl} acetamide (UCM765), is here shown to selectively promote non-rapid eye movement sleep (NREMS) in rats and mice. The enhancement of NREMS by UCM765 is nullified by the pharmacological blockade or genetic deletion of MT(2) receptors. MT(2), but not MT(1), knock-out mice show a decrease in NREMS compared to the wild strain. Immunohistochemical labeling reveals that MT(2) receptors are localized in sleep-related brain regions, and notably the reticular thalamic nucleus (Rt). Microinfusion of UCM765 in the Rt promotes NREMS, and its systemic administration induces an increase in firing and rhythmic burst activity of Rt neurons, which is blocked by the MT(2) antagonist 4-phenyl-2-propionamidotetralin. Since developing hypnotics that increase NREMS without altering sleep architecture remains a medical challenge, MT(2) receptors may represent a novel target for the treatment of sleep disorders.

  13. Arm CT scan

    Science.gov (United States)

    CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... stopping.) A computer creates separate images of the arm area, called slices. These images can be stored, ...

  14. Picking Robot Arm Trajectory Planning Method

    National Research Council Canada - National Science Library

    Zhang Zhiyong; He Dongjian; Tang Jing Lei; Meng Lingshuai

    2014-01-01

      The picking robot arm is scheduled to complete picking tasks in the working space, to overcome the shaking vibration to improve the picking stability, its movement should follow specific consistence trajectory points...

  15. Microelectromechanical safe arm device

    Science.gov (United States)

    Roesler, Alexander W [Tijeras, NM

    2012-06-05

    Microelectromechanical (MEM) apparatus and methods for operating, for preventing unintentional detonation of energetic components comprising pyrotechnic and explosive materials, such as air bag deployment systems, munitions and pyrotechnics. The MEM apparatus comprises an interrupting member that can be moved to block (interrupt) or complete (uninterrupt) an explosive train that is part of an energetic component. One or more latching members are provided that engage and prevent the movement of the interrupting member, until the one or more latching members are disengaged from the interrupting member. The MEM apparatus can be utilized as a safe and arm device (SAD) and electronic safe and arm device (ESAD) in preventing unintentional detonations. Methods for operating the MEM apparatus include independently applying drive signals to the actuators coupled to the latching members, and an actuator coupled to the interrupting member.

  16. A Biphasic Change of Regional Blood Volume in the Frontal Cortex during Non-Rapid Eye Movement Sleep: A Near-Infrared Spectroscopy Study.

    Science.gov (United States)

    Zhang, Zhongxing; Khatami, Ramin

    2015-08-01

    Current knowledge on hemodynamics in sleep is limited because available techniques do not allow continuous recordings and mainly focus on cerebral blood flow while neglecting other important parameters, such as blood volume (BV) and vasomotor activity. Observational study. Continuous measures of hemodynamics over the left forehead and biceps were performed using near-infrared spectroscopy (NIRS) during nocturnal polysomnography in 16 healthy participants in sleep laboratory. Temporal dynamics and mean values of cerebral and muscular oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (HHb), and BV during different sleep stages were compared. A biphasic change of cerebral BV was observed which contrasted a monotonic increase of muscular BV during non-rapid eye movement sleep. A significant decrement in cerebral HbO2 and BV accompanied by an increase of HHb was recorded at sleep onset (Phase I). Prior to slow wave sleep (SWS) HbO2 and BV turned to increase whereas HHb began to decrease in subsequent Phase II suggested increased brain perfusion during SWS. The cerebral HbO2 slope correlated to BV slope in Phase I and II, but it only correlated to HHb slope in Phase II. The occurrence time of inflection points correlated to SWS latencies. Initial decrease of brain perfusion with decreased blood volume (BV) and oxygenated hemoglobin (HbO2) together with increasing muscular BV fit thermoregulation process at sleep onset. The uncorrelated and correlated slopes of HbO2 and deoxygenated hemoglobin indicate different mechanisms underlying the biphasic hemodynamic process in light sleep and slow wave sleep (SWS). In SWS, changes in vasomotor activity (i.e., increased vasodilatation) may mediate increasing cerebral and muscular BV. © 2015 Associated Professional Sleep Societies, LLC.

  17. Blood RNA biomarkers in prodromal PARK4 and rapid eye movement sleep behavior disorder show role of complexin 1 loss for risk of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Suna Lahut

    2017-05-01

    Full Text Available Parkinson's disease (PD is a frequent neurodegenerative process in old age. Accumulation and aggregation of the lipid-binding SNARE complex component α-synuclein (SNCA underlies this vulnerability and defines stages of disease progression. Determinants of SNCA levels and mechanisms of SNCA neurotoxicity have been intensely investigated. In view of the physiological roles of SNCA in blood to modulate vesicle release, we studied blood samples from a new large pedigree with SNCA gene duplication (PARK4 mutation to identify effects of SNCA gain of function as potential disease biomarkers. Downregulation of complexin 1 (CPLX1 mRNA was correlated with genotype, but the expression of other Parkinson's disease genes was not. In global RNA-seq profiling of blood from presymptomatic PARK4 indviduals, bioinformatics detected significant upregulations for platelet activation, hemostasis, lipoproteins, endocytosis, lysosome, cytokine, Toll-like receptor signaling and extracellular pathways. In PARK4 platelets, stimulus-triggered degranulation was impaired. Strong SPP1, GZMH and PLTP mRNA upregulations were validated in PARK4. When analysing individuals with rapid eye movement sleep behavior disorder, the most specific known prodromal stage of general PD, only blood CPLX1 levels were altered. Validation experiments confirmed an inverse mutual regulation of SNCA and CPLX1 mRNA levels. In the 3′-UTR of the CPLX1 gene we identified a single nucleotide polymorphism that is significantly associated with PD risk. In summary, our data define CPLX1 as a PD risk factor and provide functional insights into the role and regulation of blood SNCA levels. The new blood biomarkers of PARK4 in this Turkish family might become useful for PD prediction.

  18. Dreaming furiously? A sleep laboratory study on the dream content of people with Parkinson's disease and with or without rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Valli, Katja; Frauscher, Birgit; Peltomaa, Taina; Gschliesser, Viola; Revonsuo, Antti; Högl, Birgit

    2015-03-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) has been related to altered, action-filled, vivid, and aggressive dream content, but research comparing the possible differences in dreams of Parkinson's disease (PD) patients with and without RBD is scarce. The dream content of PD patients with and without RBD was analyzed with specific focus on action-filledness, vividness, emotional valence, and threats. A total of 69 REM and NREM dream reports were collected in the sleep laboratory, 37 from nine PD patients with RBD and 32 from six PD patients without RBD. A content analysis of (1) action-filledness (actions and environmental events); (2) vividness (emotions and cognitive activity); (3) intensity of actions, events and emotions; (4) emotional valence, and (5) threatening events was performed on the transcripts. Altogether 563 dream elements expressing action-filledness and vividness were found. There were no significant between-group differences in the number or distribution of elements reflecting action-filledness or vividness, emotional valence or threats. In within-group analyses, PD patients with RBD had significantly more negative compared to positive dreams (p = 0.012) and compared to PD patients without RBD, a tendency to have more intense actions in their dreams (p = 0.066). Based on the results of this study, there are no major between-group differences in the action-filledness, vividness, or threat content of dreams of PD patients with and without RBD. However, within-group analyses revealed that dreams were more often negatively than positively toned in PD patients with RBD. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Comparing cortical auditory processing in children with typical and atypical benign epilepsy with centrotemporal spikes: Electrophysiologic evidence of the role of non-rapid eye movement sleep abnormalities.

    Science.gov (United States)

    Filippini, Melissa; Boni, Antonella; Giannotta, Melania; Pini, Antonella; Russo, Angelo; Musti, Muriel Assunta; Guerra, Angelo; Lassonde, Maryse; Gobbi, Giuseppe

    2015-05-01

    The mismatch negativity (MMN) is an objective measure of central auditory discrimination. MMN alterations have been shown in children with language and/or developmental disorders. In benign focal epilepsies, neuropsychological disorders are often reported and linked to interictal epileptic discharges (IEDs) during non-rapid eye movement (NREM) sleep. There are few studies reporting MMN in children with benign epilepsy with centrotemporal spikes (BECTS) and sleep IEDs. Moreover, no MMN recording has yet been reported in atypical BECTS children with continuous spike-and-wave during sleep (CSWS). We retrospectively compared MMN in typical and atypical BECTS children, particularly addressing the impact of NREM sleep IEDs on auditory discrimination. Moreover, we attempted a neuropsychological characterization of patients. The MMN was recorded in 9 normal controls and 23 patients (14 typical BECTS and 9 atypical BECTS) in an oddball paradigm with syllable stimuli. MMN, sleep electroencephalography (EEG) and neuropsychological evaluation were realized in the same testing session. Measurable MMN responses to speech stimuli were identified in both the control and patient groups. A significant difference between control and atypical BECTS children was found with respect to amplitude (p = 0.0061). Atypical BECTS also showed a lower MMN amplitude with respect to typical BECTS, but this difference did not reach statistical significance (p = 0.0545). Statistical comparisons between groups revealed no differences in latency. Among the neuropsychological variables, academic difficulties were significantly more prominent in the patients with atypical BECTS (p = 0.04). CSWS EEG pattern affects auditory discrimination and may have a long-lasting impact on academic skills acquisition, whereas in typical BECTS children with a lower degree of IED NREM sleep, plastic brain reorganization or the preservation of participating networks may prevent such difficulty. Early

  20. Slow oscillating transcranial direct current stimulation during non-rapid eye movement sleep improves behavioral inhibition in attention-deficit/ hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Manuel Tobias Munz

    2015-08-01

    Full Text Available Background: Behavioral inhibition, which is a later-developing executive function (EF and anatomically located in prefrontal areas, is impaired in attention-deficit and hyperactivity disorder (ADHD. While optimal EFs have been shown to depend on efficient sleep in healthy subjects, the impact of sleep problems, frequently reported in ADHD, remains elusive. Findings of macroscopic sleep changes in ADHD are inconsistent, but there is emerging evidence for distinct microscopic changes with a focus on prefrontal cortical regions and non-rapid eye movement (non-REM slow-wave sleep. Recently, slow oscillations (SO during non-REM sleep were found to be less functional and, as such, may be involved in sleep-dependent memory impairments in ADHD. Objective: By augmenting slow-wave power through bilateral, slow oscillating transcranial direct current stimulation (so-tDCS, frequency = 0.75 Hz during non-REM sleep, we aimed to improve daytime behavioral inhibition in children with ADHD. Methods: 14 boys (10-14 yrs diagnosed with ADHD were included. In a randomized, double-blind, cross-over design, patients received so-tDCS either in the first or in the second experimental sleep night. Inhibition control was assessed with a visuomotor go/no-go task. Intrinsic alertness was assessed with a simple stimulus response task. To control for visuomotor performance, motor memory was assessed with a finger sequence tapping task. Results: SO-power was enhanced during early non-REM sleep, accompanied by slowed reaction times and decreased standard deviations of reaction times, in the go/no-go task after so-tDCS. In contrast, intrinsic alertness and motor memory performance were not improved by so-tDCS. Conclusion: Since behavioral inhibition but not intrinsic alertness or motor memory was improved by so-tDCS, our results suggest that lateral prefrontal slow oscillations during sleep might play a specific role for executive functioning in ADHD.

  1. Translational evaluation of JNJ-18038683, a 5-hydroxytryptamine type 7 receptor antagonist, on rapid eye movement sleep and in major depressive disorder.

    Science.gov (United States)

    Bonaventure, Pascal; Dugovic, Christine; Kramer, Michelle; De Boer, Peter; Singh, Jaskaran; Wilson, Sue; Bertelsen, Kirk; Di, Jianing; Shelton, Jonathan; Aluisio, Leah; Dvorak, Lisa; Fraser, Ian; Lord, Brian; Nepomuceno, Diane; Ahnaou, Abdellah; Drinkenburg, Wilhelmus; Chai, Wenying; Dvorak, Curt; Sands, Steve; Carruthers, Nicholas; Lovenberg, Timothy W

    2012-08-01

    In rodents 5-hydroxytryptamine type 7 (5-HT(7)) receptor blockade has been shown to be effective in models of depression and to increase the latency to rapid eye movement (REM) sleep and decrease REM duration. In the clinic, the REM sleep reduction observed with many antidepressants may serve as a biomarker. We report here the preclinical and clinical evaluation of a 5-HT(7) receptor antagonist, (3-(4-chlorophenyl)-1,4,5,6,7,8-hexahydro-1-(phenylmethyl)pyrazolo[3,4-d]azepine 2-hydroxy-1,2,3-propanetricarboxylate) (JNJ-18038683). In rodents, JNJ-18038683 increased the latency to REM sleep and decreased REM duration, and this effect was maintained after repeated administration for 7 days. The compound was effective in the mouse tail suspension test. JNJ-18038683 enhanced serotonin transmission, antidepressant-like behavior, and REM sleep suppression induced by citalopram in rodents. In healthy human volunteers JNJ-18038683 prolonged REM latency and reduced REM sleep duration, demonstrating that the effect of 5-HT(7) blockade on REM sleep translated from rodents to humans. Like in rats, JNJ-18038683 enhanced REM sleep suppression induced by citalopram in humans, although a drug-drug interaction could not be ruled out. In a double-blind, active, and placebo-controlled clinical trial in 225 patients suffering from major depressive disorder, neither treatment with pharmacologically active doses of JNJ-18038683 or escitalopram separated from placebo, indicating a failed study lacking assay sensitivity. Post hoc analyses using an enrichment window strategy, where all the efficacy data from sites with an implausible high placebo response [placebo group Montgomery-Åsberg Depression Rating Scale (MADRS) = 28) are removed, there was a clinically meaningful difference between JNJ-18038683 and placebo. Further clinical studies are required to characterize the potential antidepressant efficacy of JNJ-18038683.

  2. The dream-lag effect: Selective processing of personally significant events during Rapid Eye Movement sleep, but not during Slow Wave Sleep.

    Science.gov (United States)

    van Rijn, E; Eichenlaub, J-B; Lewis, P A; Walker, M P; Gaskell, M G; Malinowski, J E; Blagrove, M

    2015-07-01

    Incorporation of details from waking life events into Rapid Eye Movement (REM) sleep dreams has been found to be highest on the night after, and then 5-7 nights after events (termed, respectively, the day-residue and dream-lag effects). In experiment 1, 44 participants kept a daily log for 10 days, reporting major daily activities (MDAs), personally significant events (PSEs), and major concerns (MCs). Dream reports were collected from REM and Slow Wave Sleep (SWS) in the laboratory, or from REM sleep at home. The dream-lag effect was found for the incorporation of PSEs into REM dreams collected at home, but not for MDAs or MCs. No dream-lag effect was found for SWS dreams, or for REM dreams collected in the lab after SWS awakenings earlier in the night. In experiment 2, the 44 participants recorded reports of their spontaneously recalled home dreams over the 10 nights following the instrumental awakenings night, which thus acted as a controlled stimulus with two salience levels, high (sleep lab) and low (home awakenings). The dream-lag effect was found for the incorporation into home dreams of references to the experience of being in the sleep laboratory, but only for participants who had reported concerns beforehand about being in the sleep laboratory. The delayed incorporation of events from daily life into dreams has been proposed to reflect REM sleep-dependent memory consolidation. However, an alternative emotion processing or emotional impact of events account, distinct from memory consolidation, is supported by the finding that SWS dreams do not evidence the dream-lag effect. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Activation of phasic pontine-wave generator prevents rapid eye movement sleep deprivation-induced learning impairment in the rat: a mechanism for sleep-dependent plasticity.

    Science.gov (United States)

    Datta, Subimal; Mavanji, Vijayakumar; Ulloor, Jagadish; Patterson, Elissa H

    2004-02-11

    Animal and human studies of sleep and learning have demonstrated that training on various tasks increases subsequent rapid eye movement (REM) sleep and phasic pontine-wave (P-wave) activity, followed by improvement in performance on the learned task. It is well documented that REM sleep deprivation after learning trials blocks the expected improvement in performance on subsequent retesting. Our aim was to test whether experimentally induced P-wave generator activation could eliminate the learning impairment produced by post-training REM sleep deprivation. Rats were trained on a two-way active avoidance-learning task. Immediately thereafter, two groups of those rats received a control vehicle (100 nl saline) microinjection and one group received a carbachol (50 ng in 100 nl saline) microinjection into the P-wave generator. The carbachol-injected group and one of the two control saline microinjected groups were selectively deprived of REM sleep during a 6 hr polygraphic recording session. All rats were then tested on the avoidance-learning task. The rats that received both the control saline injection and REM sleep deprivation showed learning deficits compared with the control saline-injected rats that were allowed to sleep normally. In contrast, the rats that received the carbachol microinjection and REM sleep deprivation demonstrated normal learning. These results demonstrate, for the first time, that carbachol-induced activation of the P-wave generator prevents the memory-impairing effects of post-training REM sleep deprivation. This evidence supports our hypothesis that the activation of the P-wave generator during REM sleep deprivation enhances a physiological process of memory, which occurs naturally during post-training REM sleep.

  4. Motor-prediction improvements after virtual rehabilitation in geriatrics: frail patients reveal different learning curves for movement and postural control.

    Science.gov (United States)

    Kubicki, A; Bonnetblanc, F; Petrement, G; Mourey, F

    2014-01-01

    Postural control associated with self-paced movement is critical for balance in frail older adults. The present work aimed to investigate the effects of a 2D virtual reality-based program on postural control associated with rapid arm movement in this population. Participants in an upright standing position performed rapid arm-raising movements towards a target. Practice-related changes were assessed by pre- and post-test comparisons of hand kinematics and centre-of-pressure (CoP) displacement parameters measured in a training group and a control group. During these pre- and post-test sessions, patients have to reach towards yellow balls appearing on the screen, form a standardized upright position (with 15cm between the two malleoli). Training group patients took part in six sessions of virtual game. In this, patients were asked to reach their arm towards yellow balls appearing on the screen, from an upright position. After training, we observed improvements in arm movements and in the initial phase of CoP displacement, especially in the anticipatory postural adjustments. Learning curves for these two types of motor improvements showed different rates. These were continuous for the control of the arm movement, and discontinuous for the control of the CoP during the anticipatory postural adjustments. These results suggest that some level of motor (re)-learning is maintained in frail patients with low functional reserves. They also suggest that re-learning of anticipatory postural control (i.e. motor prediction) is less robust than explicit motor learning involved for the arm reaching. This last point should encourage clinicians to extend the training course duration, even if reaching movement improvements seems acquired, in order to automate these anticipatory postural activities. However, other studies should be done to measure the retention of these two types of learning on a longer-term period. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  5. A neural tracking and motor control approach to improve rehabilitation of upper limb movements

    Directory of Open Access Journals (Sweden)

    Schmid Maurizio

    2008-02-01

    Full Text Available Abstract Background Restoration of upper limb movements in subjects recovering from stroke is an essential keystone in rehabilitative practices. Rehabilitation of arm movements, in fact, is usually a far more difficult one as compared to that of lower extremities. For these reasons, researchers are developing new methods and technologies so that the rehabilitative process could be more accurate, rapid and easily accepted by the patient. This paper introduces the proof of concept for a new non-invasive FES-assisted rehabilitation system for the upper limb, called smartFES (sFES, where the electrical stimulation is controlled by a biologically inspired neural inverse dynamics model, fed by the kinematic information associated with the execution of a planar goal-oriented movement. More specifically, this work details two steps of the proposed system: an ad hoc markerless motion analysis algorithm for the estimation of kinematics, and a neural controller that drives a synthetic arm. The vision of the entire system is to acquire kinematics from the analysis of video sequences during planar arm movements and to use it together with a neural inverse dynamics model able to provide the patient with the electrical stimulation patterns needed to perform the movement with the assisted limb. Methods The markerless motion tracking system aims at localizing and monitoring the arm movement by tracking its silhouette. It uses a specifically designed motion estimation method, that we named Neural Snakes, which predicts the arm contour deformation as a first step for a silhouette extraction algorithm. The starting and ending points of the arm movement feed an Artificial Neural Controller, enclosing the muscular Hill's model, which solves the inverse dynamics to obtain the FES patterns needed to move a simulated arm from the starting point to the desired point. Both position error with respect to the requested arm trajectory and comparison between curvature factors

  6. A neural tracking and motor control approach to improve rehabilitation of upper limb movements.

    Science.gov (United States)

    Goffredo, Michela; Bernabucci, Ivan; Schmid, Maurizio; Conforto, Silvia

    2008-02-05

    Restoration of upper limb movements in subjects recovering from stroke is an essential keystone in rehabilitative practices. Rehabilitation of arm movements, in fact, is usually a far more difficult one as compared to that of lower extremities. For these reasons, researchers are developing new methods and technologies so that the rehabilitative process could be more accurate, rapid and easily accepted by the patient. This paper introduces the proof of concept for a new non-invasive FES-assisted rehabilitation system for the upper limb, called smartFES (sFES), where the electrical stimulation is controlled by a biologically inspired neural inverse dynamics model, fed by the kinematic information associated with the execution of a planar goal-oriented movement. More specifically, this work details two steps of the proposed system: an ad hoc markerless motion analysis algorithm for the estimation of kinematics, and a neural controller that drives a synthetic arm. The vision of the entire system is to acquire kinematics from the analysis of video sequences during planar arm movements and to use it together with a neural inverse dynamics model able to provide the patient with the electrical stimulation patterns needed to perform the movement with the assisted limb. The markerless motion tracking system aims at localizing and monitoring the arm movement by tracking its silhouette. It uses a specifically designed motion estimation method, that we named Neural Snakes, which predicts the arm contour deformation as a first step for a silhouette extraction algorithm. The starting and ending points of the arm movement feed an Artificial Neural Controller, enclosing the muscular Hill's model, which solves the inverse dynamics to obtain the FES patterns needed to move a simulated arm from the starting point to the desired point. Both position error with respect to the requested arm trajectory and comparison between curvature factors have been calculated in order to determine the

  7. Cortical Spiking Network Interfaced with Virtual Musculoskeletal Arm and Robotic Arm

    Science.gov (United States)

    Dura-Bernal, Salvador; Zhou, Xianlian; Neymotin, Samuel A.; Przekwas, Andrzej; Francis, Joseph T.; Lytton, William W.

    2015-01-01

    Embedding computational models in the physical world is a critical step towards constraining their behavior and building practical applications. Here we aim to drive a realistic musculoskeletal arm model using a biomimetic cortical spiking model, and make a robot arm reproduce the same trajectories in real time. Our cortical model consisted of a 3-layered cortex, composed of several hundred spiking model-neurons, which display physiologically realistic dynamics. We interconnected the cortical model to a two-joint musculoskeletal model of a human arm, with realistic anatomical and biomechanical properties. The virtual arm received muscle excitations from the neuronal model, and fed back proprioceptive information, forming a closed-loop system. The cortical model was trained using spike timing-dependent reinforcement learning to drive the virtual arm in a 2D reaching task. Limb position was used to simultaneously control a robot arm using an improved network interface. Virtual arm muscle activations responded to motoneuron firing rates, with virtual arm muscles lengths encoded via population coding in the proprioceptive population. After training, the virtual arm performed reaching movements which were smoother and more realistic than those obtained using a simplistic arm model. This system provided access to both spiking network properties and to arm biophysical properties, including muscle forces. The use of a musculoskeletal virtual arm and the improved control system allowed the robot arm to perform movements which were smoother than those reported in our previous paper using a simplistic arm. This work provides a novel approach consisting of bidirectionally connecting a cortical model to a realistic virtual arm, and using the system output to drive a robotic arm in real time. Our techniques are applicable to the future development of brain neuroprosthetic control systems, and may enable enhanced brain-machine interfaces with the possibility for finer control of

  8. Cortical spiking network interfaced with virtual musculoskeletal arm and robotic arm

    Directory of Open Access Journals (Sweden)

    Salvador eDura-Bernal

    2015-11-01

    Full Text Available Embedding computational models in the physical world is a critical step towards constraining their behavior and building practical applications. Here we aim to drive a realistic musculoskeletal arm model using a biomimetic cortical spiking model, and make a robot arm reproduce the same trajectories in real time. Our cortical model consisted of a 3-layered cortex, composed of several hundred spiking model-neurons, which display physiologically realistic dynamics. We interconnected the cortical model to a two-joint musculoskeletal model of a human arm, with realistic anatomical and biomechanical properties. The virtual arm received muscle excitations from the neuronal model, and fed back proprioceptive information, forming a closed-loop system. The cortical model was trained using spike timing-dependent reinforcement learning to drive the virtual arm in a 2D reaching task. Limb position was used to simultaneously control a robot arm using an improved network interface. Virtual arm muscle activations responded to motoneuron firing rates, with virtual arm muscles lengths encoded via population coding in the proprioceptive population. After training, the virtual arm performed reaching movements which were smoother and more realistic than those obtained using a simplistic arm model. This system provided access to both spiking network properties and to arm biophysical properties, including muscle forces. The use of a musculoskeletal virtual arm and the improved control system allowed the robot arm to perform movements which were smoother than those reported in our previous paper using a simplistic arm.This work provides a novel approach consisting of bidirectionally connecting a cortical model to a realistic virtual arm, and using the system output to drive a robotic arm in real time. Our techniques are applicable to the future development of brain neuro-prosthetic control systems, and may enable enhanced brain-machine interfaces with the possibility

  9. Cortical Spiking Network Interfaced with Virtual Musculoskeletal Arm and Robotic Arm.

    Science.gov (United States)

    Dura-Bernal, Salvador; Zhou, Xianlian; Neymotin, Samuel A; Przekwas, Andrzej; Francis, Joseph T; Lytton, William W

    2015-01-01

    Embedding computational models in the physical world is a critical step towards constraining their behavior and building practical applications. Here we aim to drive a realistic musculoskeletal arm model using a biomimetic cortical spiking model, and make a robot arm reproduce the same trajectories in real time. Our cortical model consisted of a 3-layered cortex, composed of several hundred spiking model-neurons, which display physiologically realistic dynamics. We interconnected the cortical model to a two-joint musculoskeletal model of a human arm, with realistic anatomical and biomechanical properties. The virtual arm received muscle excitations from the neuronal model, and fed back proprioceptive information, forming a closed-loop system. The cortical model was trained using spike timing-dependent reinforcement learning to drive the virtual arm in a 2D reaching task. Limb position was used to simultaneously control a robot arm using an improved network interface. Virtual arm muscle activations responded to motoneuron firing rates, with virtual arm muscles lengths encoded via population coding in the proprioceptive population. After training, the virtual arm performed reaching movements which were smoother and more realistic than those obtained using a simplistic arm model. This system provided access to both spiking network properties and to arm biophysical properties, including muscle forces. The use of a musculoskeletal virtual arm and the improved control system allowed the robot arm to perform movements which were smoother than those reported in our previous paper using a simplistic arm. This work provides a novel approach consisting of bidirectionally connecting a cortical model to a realistic virtual arm, and using the system output to drive a robotic arm in real time. Our techniques are applicable to the future development of brain neuroprosthetic control systems, and may enable enhanced brain-machine interfaces with the possibility for finer control of

  10. Rapid eye movement sleep loss induces neuronal apoptosis in the rat brain by noradrenaline acting on alpha 1-adrenoceptor and by triggering mitochondrial intrinsic pathway

    Directory of Open Access Journals (Sweden)

    Bindu I Somarajan

    2016-03-01

    Full Text Available Many neurodegenerative disorders are associated with rapid eye movement sleep (REMS-loss, however the mechanism was unknown. As REMS-loss elevates noradrenaline (NA level in the brain as well as induces neuronal apoptosis and degeneration, in this study we have delineated the intracellular molecular pathway involved in REMS deprivation (REMSD associated NA-induced neuronal apoptosis. Rats were REMS deprived for 6 days by the classical flower-pot method, suitable controls were conducted and the effects on apoptosis markers evaluated. Further, the role of NA was studied by one, intraperitoneal (i.p. injection of NA-ergic alpha1-adrenoceptor antagonist prazosin (PRZ and two, by down-regulation of NA synthesis in locus coeruleus (LC neurons by local microinjection of tyrosine hydroxylase siRNA (TH-siRNA. Immunoblot estimates showed that the expressions of pro-apoptotic proteins viz. Bcl2-associated death promoter (BAD protein, apoptotic protease activating factor-1 (Apaf-1, cytochrome c, caspase9, caspase3 were elevated in the REMS-deprived rat brains, while caspase8 level remained unaffected; PRZ treatment did not allow elevation of these pro-apoptotic factors. Further, REMSD increased cytochrome c expression, which was prevented if the NA synthesis from the LC neurons was blocked by microinjection of TH-siRNA in vivo into the LC during REMSD in freely moving normal rats. Mitochondrial damage was re-confirmed by transmission electron microscopy (TEM, which showed distinctly swollen mitochondria with disintegrated cristae, chromosomal condensation and clumping along the nuclear membrane and all these changes were prevented in PRZ treated rats. Combining findings of this study along with earlier reports we propose that upon REMSD NA level increases in the brain as the LC NA-ergic REM-OFF neurons do not cease firing and TH is up-regulated in those neurons. This elevated NA acting on alpha1-adrenoceptors damages mitochondria causing release of

  11. Rapid eye movement sleep without atonia may help diagnose Lewy body disease in middle-aged and older patients with somatic symptom disorder.

    Science.gov (United States)

    Munechika, Takayuki; Fujishiro, Hiroshige; Okuda, Masato; Iwamoto, Kunihiro; Torii, Youta; Iritani, Shuji; Ozaki, Norio

    2017-01-01

    Lewy body disease (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB), is defined pathologically as degeneration in the central and peripheral nervous system associated with Lewy bodies. Somatic symptom disorder often predates the clinical diagnosis of PD and DLB. It is crucial to make an initial diagnosis of LBD in patients with psychiatric symptoms because administering psychotropic drugs often causes or exacerbates extrapyramidal signs. Given the close association between rapid eye movement (REM) sleep behaviour disorder and LBD, REM sleep without atonia on polysomnography may help to diagnose LBD in middle-aged and older patients with somatic symptom disorder. We reviewed the clinical profiles of five patients with an initial diagnosis of somatic symptom disorder who exhibited REM sleep without atonia on polysomnography. There were three men and two women, with a mean age of 68.4 years (range: 55.0-78.0 years). The mean Mini-Mental State Examination score was 26 (range: 22-30). Only two patients had a clinical history of dream-enacting behaviour and fulfilled the clinical criteria for REM sleep behaviour disorder, but clinical conditions in the other three patients corresponded to subclinical REM sleep behaviour disorder. Final clinical diagnoses were made as probable DLB in three patients; two patients did not meet the clinical criteria for PD or DLB. Neurological examinations revealed mild extrapyramidal signs in these two patients, and their scores on the motor component of the Unified Parkinson's Disease Rating Scale were 8 and 5 points, and their Mini-Mental State Examination scores were 30 points. Neither patient exhibited dream-enacting behaviour, but both had constipation. Cardiac 123 I-metaiodobenzylguanidine scintigraphy revealed mild increased washout rates. REM sleep without atonia may provide an opportunity to identify LBD in patients with somatic symptom disorder, even before they fulfil the clinical criteria for PD or

  12. A pilot study of serotonin-1A receptor genotypes and rapid eye movement sleep sensitivity to serotonergic/cholinergic imbalance in humans: a pharmacological model of depression

    Directory of Open Access Journals (Sweden)

    Biard K

    2015-12-01

    Full Text Available Kathleen Biard,1,2 Alan B Douglass,2,3 Rébecca Robillard,2 Joseph De Koninck1,2 1School of Psychology, University of Ottawa, 2University of Ottawa Institute for Mental Health Research, 3Royal Ottawa Mental Health Center, University of Ottawa Institute for Mental Health Research, Ottawa, ON, Canada Rationale: The serotonergic and cholinergic systems are jointly involved in regulating sleep but this system is theorized to be disturbed in depressed individuals. We previously reported that cholinergic and serotonergic agents induce sleep changes partially consistent with monoamine models of sleep disturbances in depression. One potential cause of disturbed neurotransmission is genetic predisposition. The G(-1019 allele of the serotonin-1A (5-HT1A receptor promoter region predicts an increased risk for depression compared to the wild-type C(-1019 allele. Objective: The goal of this study was to investigate how serotonin-1A receptor genotypes mediate sleep sensitivity to pharmacological probes modeling the serotonergic/cholinergic imbalance of depression. Methods: Seventeen healthy female participants homozygous for either C (n=11 or G (n=6 alleles aged 18–27 years were tested on four nonconsecutive nights. Participants were given galantamine (an anti-acetylcholinesterase, buspirone (a serotonergic agonist, both drugs together, or placebos before sleeping. Results: As reported previously, buspirone significantly increased rapid eye movement (REM latency (P<0.001, as well as awakenings, percentage of time spent awake, and percentage of time asleep spent in stage N1 (P<0.019. Galantamine increased awakenings, percentage of time spent awake, percentage of time asleep spent in stage N1, and percentage of time asleep spent in REM, and decreased REM latency and percentage of time asleep spent in stage N3 (P<0.019. Galantamine plus buspirone given together disrupted sleep more than either drug alone, lowering sleep efficiency and percentage of time asleep

  13. Rapid touch-stimulated movement in the androgynophore of Passiflora flowers (subgen. Decaloba; Sect. Xerogona): an adaptation to enhance cross-pollination?

    Science.gov (United States)

    Scorza, Livia C T; Dornelas, Marcelo Carnier

    2014-01-01

    Plant touch-sensitive organs have been described since Darwin's observations and are related to a quick response to environment stimuli. Sensitive flower organs have been associated to an increase in the chances of cross pollination but there are few studies regarding this topic. Here we describe for the first time the kinetic of the androgynophore movement of 4 Passiflora species (P. sanguinolenta, P. citrina, P. capsularis, and P. rubra). For that, we collected flowers and recorded the movement after mechano-stimulating the androgynophore. From the recordings, we described the movement regarding its response and sensibility to mechanical stimulus and calculated the duration, speed, and the angle formed by the androgynophore before and after the movement. From our data we were able to propose a link to the pollination habit of these species. The movement of the androgynophore in these Passiflora is a noteworthy floral feature that might lead us to another astonishing example of a mechanism that evolved among angiosperms to assure sexual reproduction.

  14. Neurodegenerative disease status and post-mortem pathology in idiopathic rapid-eye-movement sleep behaviour disorder: an observational cohort study.

    Science.gov (United States)

    Iranzo, Alex; Tolosa, Eduard; Gelpi, Ellen; Molinuevo, José Luis; Valldeoriola, Francesc; Serradell, Mónica; Sanchez-Valle, Raquel; Vilaseca, Isabel; Lomeña, Francisco; Vilas, Dolores; Lladó, Albert; Gaig, Carles; Santamaria, Joan

    2013-05-01

    We postulated that idiopathic rapid-eye-movement (REM) sleep behaviour disorder (IRBD) represents the prodromal phase of a Lewy body disorder and that, with sufficient follow-up, most cases would eventually be diagnosed with a clinical defined Lewy body disorder, such as Parkinson's disease (PD) or dementia with Lewy bodies (DLB). Patients from an IRBD cohort recruited between 1991 and 2003, and previously assessed in 2005, were followed up during an additional period of 7 years. In this original cohort, we sought to identify the nature and frequency of emerging defined neurodegenerative syndromes diagnosed by standard clinical criteria. We estimated rates of survival free from defined neurodegenerative disease by means of the Kaplan-Meier method. We further characterised individuals who remained diagnosed as having only IRBD, through dopamine transporter (DAT) imaging, transcranial sonography (TCS), and olfactory testing. We did a neuropathological assessment in three patients who died during follow-up and who had the antemortem diagnosis of PD or DLB. Of the 44 participants from the original cohort, 36 (82%) had developed a defined neurodegenerative syndrome by the 2012 assessment (16 patients were diagnosed with PD, 14 with DLB, one with multiple system atrophy, and five with mild cognitive impairment). The rates of neurological-disease-free survival from time of IRBD diagnosis were 65·2% (95% CI 50·9 to 79·5) at 5 years, 26·6% (12·7 to 40·5) at 10 years, and 7·5% (-1·9 to 16·9) at 14 years. Of the four remaining neurological-disease-free individuals who underwent neuroimaging and olfactory tests, all four had decreased striatal DAT uptake, one had substantia nigra hyperechogenicity on TCS, and two had impaired olfaction. In three patients, the antemortem diagnoses of PD and DLB were confirmed by neuropathological examination showing widespread Lewy bodies in the brain, and α-synuclein aggregates in the peripheral autonomic nervous system in one case

  15. Procalcitonin for selecting the antibiotic regimen in outpatients with low-risk community-acquired pneumonia using a rapid point-of-care testing: A single-arm clinical trial.

    Directory of Open Access Journals (Sweden)

    Mar Masiá

    Full Text Available We aimed to assess the role of procalcitonin (PCT to guide the initial selection of the antibiotic regimen for low-risk community-acquired pneumonia (CAP.A single-arm clinical trial was conducted including outpatients with CAP and Pneumonia Severity Index risk classes I-II. Antimicrobial selection was based on the results of PCT measured with a rapid point-of-care testing. According to serum PCT levels, patients were assigned to two treatment strategies: oral azithromycin if PCT was <0.5 ng/ml, or levofloxacin if levels were ≥0.5 ng/ml. Primary outcome was clinical cure rate. Short-term and long-term outcomes were assessed. Results were compared with those of a historical standard-of-care control-group treated in our centre.Of 253 subjects included, 216 (85.4% were assigned to azithromycin. Pneumococcal infection was diagnosed in 26 (12% and 21 (56.8% patients allocated to azithromycin and levofloxacin groups, respectively. No patients in the azithromycin group developed bacteraemia. Atypical organisms were more common in patients given azithromycin (18.5% vs 8.1%, respectively. The majority (93% of patients with atypical pneumonia had low PCT levels. Clinical cure rates were 95.8% in the azithromycin group, 94.6% in the levofloxacin group, and 94.4% in the historical control group. No 30-day mortality or recurrences were observed, and the 3-year rates of recurrence and mortality were very low in both groups. Adverse events occurrence was also infrequent.A PCT-guided strategy with a rapid point-of-care testing safely allowed selecting empirical narrow-spectrum antibiotics in outpatients with CAP.The study is registered with ClinicalTrials.gov, number NCT02600806.

  16. Procalcitonin for selecting the antibiotic regimen in outpatients with low-risk community-acquired pneumonia using a rapid point-of-care testing: A single-arm clinical trial.

    Science.gov (United States)

    Masiá, Mar; Padilla, Sergio; Ortiz de la Tabla, Victoria; González, Matilde; Bas, Cristina; Gutiérrez, Félix

    2017-01-01

    We aimed to assess the role of procalcitonin (PCT) to guide the initial selection of the antibiotic regimen for low-risk community-acquired pneumonia (CAP). A single-arm clinical trial was conducted including outpatients with CAP and Pneumonia Severity Index risk classes I-II. Antimicrobial selection was based on the results of PCT measured with a rapid point-of-care testing. According to serum PCT levels, patients were assigned to two treatment strategies: oral azithromycin if PCT was <0.5 ng/ml, or levofloxacin if levels were ≥0.5 ng/ml. Primary outcome was clinical cure rate. Short-term and long-term outcomes were assessed. Results were compared with those of a historical standard-of-care control-group treated in our centre. Of 253 subjects included, 216 (85.4%) were assigned to azithromycin. Pneumococcal infection was diagnosed in 26 (12%) and 21 (56.8%) patients allocated to azithromycin and levofloxacin groups, respectively. No patients in the azithromycin group developed bacteraemia. Atypical organisms were more common in patients given azithromycin (18.5% vs 8.1%, respectively). The majority (93%) of patients with atypical pneumonia had low PCT levels. Clinical cure rates were 95.8% in the azithromycin group, 94.6% in the levofloxacin group, and 94.4% in the historical control group. No 30-day mortality or recurrences were observed, and the 3-year rates of recurrence and mortality were very low in both groups. Adverse events occurrence was also infrequent. A PCT-guided strategy with a rapid point-of-care testing safely allowed selecting empirical narrow-spectrum antibiotics in outpatients with CAP. The study is registered with ClinicalTrials.gov, number NCT02600806.

  17. Developmental trends in speed accuracy trade-off in 6-10-year-old children performing rapid reciprocal and discrete aiming movements.

    NARCIS (Netherlands)

    Smits-Engelsman, B.C.M.; Sugden, D.A.; Duysens, J.E.J.

    2006-01-01

    Cyclic tasks are performed better than discrete tasks in adults but it is unknown whether this advantage is present in children as well. Three age groups of participants (6, 8, and 10 years old) executed cyclic and discrete aiming movements to two differently sized target using a Fitts task to

  18. Developmental trends in speed accuracy trade-off in 6-10-year-old children performing rapid reciprocal and discrete aiming movements

    NARCIS (Netherlands)

    Smits-Engelsman, B.C.M.; Sugden, D.A.; Duysens, J.E.J.

    2006-01-01

    Cyclic tasks are performed better than discrete tasks in adults but it is unknown whether this advantage is present in children as well. Three age groups of participants (6, 8, and 10 years old) executed cyclic and discrete aiming movements to two differently sized target using a Fitts task to

  19. Rhythmic upper-limb therapy improves both rhythmic and discrete movement features after stroke

    OpenAIRE

    Leconte, Patricia; Ronsse, Renaud; 13th Belgian day on biomedical engineering

    2014-01-01

    Rhythmic and discrete movements are two fundamental classes of upper-limb movements recruiting, at least partially, distinct neural circuitries. Current post-stroke upper-limb rehabilitation focuses on intensive task-oriented movement leaving aside rhythmic arm movement. The present study aims at determining whether rhythmic arm training should be part of post-stroke upper-limb rehabilitation.

  20. Observing virtual arms that you imagine are yours increases the galvanic skin response to an unexpected threat.

    Directory of Open Access Journals (Sweden)

    Karin Hägni

    Full Text Available Multi-modal visuo-tactile stimulation of the type performed in the rubber hand illusion can induce the brain to temporarily incorporate external objects into the body image. In this study we show that audio-visual stimulation combined with mental imagery more rapidly elicits an elevated physiological response (skin conductance after an unexpected threat to a virtual limb, compared to audio-visual stimulation alone. Two groups of subjects seated in front of a monitor watched a first-person perspective view of slow movements of two virtual arms intercepting virtual balls rolling towards the viewer. One group was instructed to simply observe the movements of the two virtual arms, while the other group was instructed to observe the virtual arms and imagine that the arms were their own. After 84 seconds the right virtual arm was unexpectedly "stabbed" by a knife and began "bleeding". This aversive stimulus caused both groups to show a significant increase in skin conductance. In addition, the observation-with-imagery group showed a significantly higher skin conductance (p<0.05 than the observation-only group over a 2-second period shortly after the aversive stimulus onset. No corresponding change was found in subjects' heart rates. Our results suggest that simple visual input combined with mental imagery may induce the brain to measurably temporarily incorporate external objects into its body image.

  1. Trunk Postural Muscle Timing Is Not Compromised In Low Back Pain Patients Clinically Diagnosed With Movement Coordination Impairments.

    Science.gov (United States)

    Mehta, Rupal; Cannella, Marco; Henry, Sharon M; Smith, Susan; Giszter, Simon; Silfies, Sheri P

    2017-04-01

    Trunk muscle timing impairment has been associated with nonspecific low back pain (NSLBP), but this finding has not been consistent. This study investigated trunk muscle timing in a subgroup of patients with NSLBP attributed to movement coordination impairment (MCI) and matched asymptomatic controls in response to a rapid arm-raising task. Twenty-one NSLBP subjects and 21 matched controls had arm motion and surface EMG data collected from seven bilateral trunk muscles. Muscle onset and offset relative to deltoid muscle activation and arm motion, duration of muscle burst and abdominal-extensor co-contraction time were derived. Trunk muscle onset and offset latencies, and burst and co-contraction durations were not different (p > .05) between groups. Patterns of trunk muscle activation and deactivation relative to arm motion were not different. Task performance was similar between groups. Trunk muscle timing does not appear to be an underlying impairment in the subgroup of NSLBP with MCI.

  2. Arm Lift (Brachioplasty)

    Science.gov (United States)

    Tests and Procedures Arm lift By Mayo Clinic Staff An arm lift — also known as brachioplasty — is a cosmetic surgical procedure to improve ... appearance of the under portion of your upper arms. During an arm lift, excess skin and fat ...

  3. Context-Dependent Arm Pointing Adaptation

    Science.gov (United States)

    Seidler, R. D.; Bloomberg, J. J.; Stelmach, G. E.

    2000-01-01

    We sought to determine the effectiveness of head posture as a contextual cue to facilitate adaptive transitions in manual control during visuomotor distortions. Subjects performed arm pointing movements by drawing on a digitizing tablet, with targets and movement trajectories displayed in real time on a computer monitor. Adaptation was induced by presenting the trajectories in an altered gain format on the monitor. The subjects were shown visual displays of their movements that corresponded to either 0.5 or 1.5 scaling of the movements made. Subjects were assigned to three groups: the head orientation group tilted the head towards the right shoulder when drawing under a 0.5 gain of display and towards the left shoulder when drawing under a 1.5 gain of display, the target orientation group had the home & target positions rotated counterclockwise when drawing under the 0.5 gain and clockwise for the 1.5 gain, the arm posture group changed the elbow angle of the arm they were not drawing with from full flexion to full extension with 0.5 and 1.5 gain display changes. To determine if contextual cues were associated with display alternations, the gain changes were returned to the standard (1.0) display. Aftereffects were assessed to determine the efficacy of the head orientation contextual cue. . compared to the two control cues. The head orientation cue was effectively associated with the multiple gains. The target orientation cue also demonstrated some effectiveness while the.arm posture cue did not. The results demonstrate that contextual cues can be used to switch between multiple adaptive states. These data provide support for the idea that static head orientation information is a crucial component to the arm adaptation process. These data further define the functional linkage between head posture and arm pointing movements.

  4. The Musculature of Coleoid Cephalopod Arms and Tentacles

    Science.gov (United States)

    Kier, William M.

    2016-01-01

    The regeneration of coleoid cephalopod arms and tentacles is a common occurrence, recognized since Aristotle. The complexity of the arrangement of the muscle and connective tissues of these appendages make them of great interest for research on regeneration. They lack rigid skeletal elements and consist of a three-dimensional array of muscle fibers, relying on a type of skeletal support system called a muscular hydrostat. Support and movement in the arms and tentacles depends on the fact that muscle tissue resists volume change. The basic principle of function is straightforward; because the volume of the appendage is essentially constant, a decrease in one dimension must result in an increase in another dimension. Since the muscle fibers are arranged in three mutually perpendicular directions, all three dimensions can be actively controlled and thus a remarkable diversity of movements and deformations can be produced. In the arms and tentacles of coleoids, three main muscle orientations are observed: (1) transverse muscle fibers arranged in planes perpendicular to the longitudinal axis; (2) longitudinal muscle fibers typically arranged in bundles parallel to the longitudinal axis; and (3) helical or obliquely arranged layers of muscle fibers, arranged in both right- and left-handed helixes. By selective activation of these muscle groups, elongation, shortening, bending, torsion and stiffening of the appendage can be produced. The predominant muscle fiber type is obliquely striated. Cross-striated fibers are found only in the transverse muscle mass of the prey capture tentacles of squid and cuttlefish. These fibers have unusually short myofilaments and sarcomeres, generating the high shortening velocity required for rapid elongation of the tentacles. It is likely that coleoid cephalopods use ultrastructural modifications rather than tissue-specific myosin isoforms to tune contraction velocities. PMID:26925401

  5. Effort, success, and nonuse determine arm choice

    Science.gov (United States)

    Xiao, Yupeng; Kim, Sujin; Yoshioka, Toshinori; Gordon, James; Osu, Rieko

    2015-01-01

    How do humans choose one arm or the other to reach single targets in front of the body? Current theories of reward-driven decisionmaking predict that choice results from a comparison of “action values,” which are the expected rewards for possible actions in a given state. In addition, current theories of motor control predict that in planning arm movements, humans minimize an expected motor cost that balances motor effort and endpoint accuracy. Here, we test the hypotheses that arm choice is determined by comparison of action values comprising expected effort and expected task success for each arm, as well as a handedness bias. Right-handed subjects, in either a large or small target condition, were first instructed to use each hand in turn to shoot through an array of targets and then to choose either hand to shoot through the same targets. Effort was estimated via inverse kinematics and dynamics. A mixed-effects logistic-regression analysis showed that, as predicted, both expected effort and expected success predicted choice, as did arm use in the preceding trial. Finally, individual parameter estimation showed that the handedness bias correlated with mean difference between right- and left-arm success, leading to overall lower use of the left arm. We discuss our results in light of arm nonuse in individuals' poststroke. PMID:25948869

  6. Bowel Movement

    Science.gov (United States)

    ... passes through the large intestine too slowly. Bowel incontinence is a problem controlling your bowel movements. Other abnormalities with bowel movements may be a sign of a digestive problem. NIH: National Institute of Diabetes and Digestive and Kidney Diseases

  7. Eye movements in depth to visual illusions

    Science.gov (United States)

    Wismeijer, D. A.

    2009-10-01

    We perceive the three-dimensional (3D) environment that surrounds us with deceptive effortlessness. In fact, we are far from comprehending how the visual system provides us with this stable perception of the (3D) world around us. This thesis will focus on the interplay between visual perception of depth and its closely related action system, eye movements in depth. The human visual system is comprised of a sensory (input) and an output (motor) system. Processed information from the sensory system can result in two explicit measurable response types: conscious visual perception and ocular motor behavior. It is still a matter of debate whether conscious visual perception and action (including hand- and arm-movements) use the same information or whether the visual system has separate channels processing information for perception and action. In this thesis, we study (1) if separate channels, one for eye movements and one for conscious visual perception, indeed exist, and (2) if so, if there is a direct input from the perceptual pathway to the motor pathway. Assuming that either eye movements and conscious visual perception are based on information from a common source (a negative answer to issue 1) or perception can directly influence, or guide, eye movements (an affirmative answer to research question 2), (eye) movements reflect our conscious visual perception. If so, eye movements could provide us with an alternative method to probe our conscious visual perception, making explicit perceptual reports superfluous. In this thesis we focus on depth perception and the two types of eye movements that are closest related to depth perception, namely vergence (an eye movement that gets a certain depth plane into focus) and saccades (a rapid eye movement to change gaze direction). Over the last 20 years it has been shown that depth perception is based on a weighted combination of depth cues available such as linear perspective, occlusion and binocular disparity. How eye

  8. The effects of additional arm weights on arm-swing magnitude and gait patterns in Parkinson's disease.

    Science.gov (United States)

    Yoon, Jiyeon; Park, Jinse; Park, Kunbo; Jo, Geunyeol; Kim, Haeyu; Jang, Wooyoung; Kim, Ji Sun; Youn, Jinyoung; Oh, Eung Seok; Kim, Hee-Tae; Youm, Chang Hong

    2016-01-01

    Recently, arm facilitation has been interested in gait rehabilitation. However, there have been few studies concerning arm facilitation in patients with Parkinson's disease (PD). The aim of our study was to investigate the effect of increasing arm weights on gait pattern in patients with PD. Twenty-seven patients with PD were enrolled, and they underwent gait analysis using a three-dimensional motion capture system. Sandbags were applied to the distal forearms in all participants. We compared gait parameters including arm swing, pelvic motion, spatiotemporal data, and relative rotational angle between the weighted and unweighted gaits. The total arm-swing amplitude and pelvic rotation were significantly higher when walking with additional arm weights than without arm weights. Cadence, walking speed, stride length, and swing phase were significantly higher, whereas stride time, double-support time, and stance phase were significantly lower, when walking with additional arm weights than without arm weights. We conclude that adding weights to the arm during walking may facilitate arm and pelvic movements, which results in changes to gait patterns. The therapeutic use of additional arm weights could be considered for gait rehabilitation in PD to improve gait impairment. Arm-swing facilitation using weight load improved gait in Parkinson's disease. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  9. Robots testing robots: ALAN-Arm, a humanoid arm for the testing of robotic rehabilitation systems.

    Science.gov (United States)

    Brookes, Jack; Kuznecovs, Maksims; Kanakis, Menelaos; Grigals, Arturs; Narvidas, Mazvydas; Gallagher, Justin; Levesley, Martin

    2017-07-01

    Robotics is increasing in popularity as a method of providing rich, personalized and cost-effective physiotherapy to individuals with some degree of upper limb paralysis, such as those who have suffered a stroke. These robotic rehabilitation systems are often high powered, and exoskeletal systems can attach to the person in a restrictive manner. Therefore, ensuring the mechanical safety of these devices before they come in contact with individuals is a priority. Additionally, rehabilitation systems may use novel sensor systems to measure current arm position. Used to capture and assess patient movements, these first need to be verified for accuracy by an external system. We present the ALAN-Arm, a humanoid robotic arm designed to be used for both accuracy benchmarking and safety testing of robotic rehabilitation systems. The system can be attached to a rehabilitation device and then replay generated or human movement trajectories, as well as autonomously play rehabilitation games or activities. Tests of the ALAN-Arm indicated it could recreate the path of a generated slow movement path with a maximum error of 14.2mm (mean = 5.8mm) and perform cyclic movements up to 0.6Hz with low gain (<1.5dB). Replaying human data trajectories showed the ability to largely preserve human movement characteristics with slightly higher path length and lower normalised jerk.

  10. An automated image-based method of 3D subject-specific body segment parameter estimation for kinetic analyses of rapid movements.

    Science.gov (United States)

    Sheets, Alison L; Corazza, Stefano; Andriacchi, Thomas P

    2010-01-01

    Accurate subject-specific body segment parameters (BSPs) are necessary to perform kinetic analyses of human movements with large accelerations, or no external contact forces or moments. A new automated topographical image-based method of estimating segment mass, center of mass (CM) position, and moments of inertia is presented. Body geometry and volume were measured using a laser scanner, then an automated pose and shape registration algorithm segmented the scanned body surface, and identified joint center (JC) positions. Assuming the constant segment densities of Dempster, thigh and shank masses, CM locations, and moments of inertia were estimated for four male subjects with body mass indexes (BMIs) of 19.7-38.2. The subject-specific BSP were compared with those determined using Dempster and Clauser regression equations. The influence of BSP and BMI differences on knee and hip net forces and moments during a running swing phase were quantified for the subjects with the smallest and largest BMIs. Subject-specific BSP for 15 body segments were quickly calculated using the image-based method, and total subject masses were overestimated by 1.7-2.9%.When compared with the Dempster and Clauser methods, image-based and regression estimated thigh BSP varied more than the shank parameters. Thigh masses and hip JC to thigh CM distances were consistently larger, and each transverse moment of inertia was smaller using the image-based method. Because the shank had larger linear and angular accelerations than the thigh during the running swing phase, shank BSP differences had a larger effect on calculated intersegmental forces and moments at the knee joint than thigh BSP differences did at the hip. It was the net knee kinetic differences caused by the shank BSP differences that were the largest contributors to the hip variations. Finally, BSP differences produced larger kinetic differences for the subject with larger segment masses, suggesting that parameter accuracy is more

  11. Arm Injuries and Disorders

    Science.gov (United States)

    ... your body, three of them are in your arm: the humerus, radius, and ulna. Your arms are also made up of muscles, joints, tendons, ... Injuries to any of these parts of the arm can occur during sports, a fall, or an ...

  12. [Stereotypic movements].

    Science.gov (United States)

    Fernández-Alvarez, E

    2003-02-01

    Stereotypic movements are repetitive patterns of movement with certain peculiar features that make them especially interesting. Their physiopathology and their relationship with the neurobehavioural disorders they are frequently associated with are unknown. In this paper our aim is to offer a simple analysis of their dominant characteristics, their differentiation from other processes and a hypothesis of the properties of stereotypic movements, which could all set the foundations for research work into their physiopathology.

  13. Arm Swing during Walking at Different Speeds in Children with Cerebral Palsy and Typically Developing Children

    Science.gov (United States)

    Meyns, Pieter; Van Gestel, Leen; Massaad, Firas; Desloovere, Kaat; Molenaers, Guy; Duysens, Jacques

    2011-01-01

    Children with Cerebral Palsy (CP) have difficulties walking at a normal or high speed. It is known that arm movements play an important role to achieve higher walking speeds in healthy subjects. However, the role played by arm movements while walking at different speeds has received no attention in children with CP. Therefore we investigated the…

  14. Neural control of rhythmic arm cycling after stroke

    Science.gov (United States)

    Loadman, Pamela M.; Hundza, Sandra R.

    2012-01-01

    Disordered reflex activity and alterations in the neural control of walking have been observed after stroke. In addition to impairments in leg movement that affect locomotor ability after stroke, significant impairments are also seen in the arms. Altered neural control in the upper limb can often lead to altered tone and spasticity resulting in impaired coordination and flexion contractures. We sought to address the extent to which the neural control of movement is disordered after stroke by examining the modulation pattern of cutaneous reflexes in arm muscles during arm cycling. Twenty-five stroke participants who were at least 6 mo postinfarction and clinically stable, performed rhythmic arm cycling while cutaneous reflexes were evoked with trains (5 × 1.0-ms pulses at 300 Hz) of constant-current electrical stimulation to the superficial radial (SR) nerve at the wrist. Both the more (MA) and less affected (LA) arms were stimulated in separate trials. Bilateral electromyography (EMG) activity was recorded from muscles acting at the shoulder, elbow, and wrist. Analysis was conducted on averaged reflexes in 12 equidistant phases of the movement cycle. Phase-modulated cutaneous reflexes were present, but altered, in both MA and LA arms after stroke. Notably, the pattern was “blunted” in the MA arm in stroke compared with control participants. Differences between stroke and control were progressively more evident moving from shoulder to wrist. The results suggest that a reduced pattern of cutaneous reflex modulation persists during rhythmic arm movement after stroke. The overall implication of this result is that the putative spinal contributions to rhythmic human arm movement remain accessible after stroke, which has translational implications for rehabilitation. PMID:22572949

  15. Arm motion coupling during locomotion-like actions: An experimental study and a dynamic model

    Science.gov (United States)

    Shapkova, E.Yu; Terekhov, A.V.; Latash, M.L.

    2010-01-01

    We studied the coordination of arm movements in standing persons who performed an out-of-phase arm-swinging task while stepping in place or while standing. The subjects were instructed to stop one of the arms in response to an auditory signal while trying to keep the rest of the movement pattern unchanged. A significant increase was observed in the amplitude of the arm that continued swinging under both the stepping and standing conditions. This increase was similar between the right and left arms. A dynamic model was developed including two coupled non-linear van der Pol oscillators. We assumed that stopping an arm did not eliminate the coupling but introduced a new constraint. Within the model, superposition of two factors, a command to stop the ongoing movement of one arm and the coupling between the two oscillators, has been able to account for the observed effects. The model makes predictions for future experiments. PMID:21628725

  16. Training the Unimpaired Arm Improves the Motion of the Impaired Arm and the Sitting Balance in Chronic Stroke Survivors.

    Science.gov (United States)

    De Luca, Alice; Giannoni, Psiche; Vernetti, Honore; Capra, Cristina; Lentino, Carmelo; Checchia, Giovanni Antonio; Casadio, Maura

    2017-07-01

    Robot-assisted rehabilitation of stroke survivors mainly focuses on the impaired side of the body while the role of the unimpaired side in the recovery after stroke is still controversial. The goal of this study is to investigate the influence on sitting balance and paretic arm functions of a training protocol based on movements of the unimpaired arm. Sixteen chronic stroke survivors underwent nineteen training sessions, in which they performed active movements with the unimpaired arm supported by a passive exoskeleton. Performance of the trunk and upper limbs was evaluated before treatment, after treatment and at six months follow up with clinical scales and an instrumented evaluation. A reaching test executed with the exoskeleton was used to assess changes in performance of both arms. The treatment based on the unimpaired arm's movements executed with a correct body posture led to benefits in control of the trunk and of both the trained and the untrained arm. The amount of impaired arm improvement in the Fugl-Meyer score was comparable to the outcome of robotic treatments focused directly on this arm. Our results highlight the importance of taking into account all body schema in the rehabilitation robotic program, instead of focusing only on the impaired side of the body.

  17. Explicit motor sequence learning with the paretic arm after stroke.

    Science.gov (United States)

    Fleming, Melanie K; Newham, Di J; Rothwell, John C

    2018-02-01

    Motor sequence learning is important for stroke recovery, but experimental tasks require dexterous movements, which are impossible for people with upper limb impairment. This makes it difficult to draw conclusions about the impact of stroke on learning motor sequences. We aimed to test a paradigm requiring gross arm movements to determine whether stroke survivors with upper limb impairment were capable of learning a movement sequence as effectively as age-matched controls. In this case-control study, 12 stroke survivors (10-138 months post-stroke, mean age 64 years) attempted the task once using their affected arm. Ten healthy controls (mean 66 years) used their non-dominant arm. A sequence of 10 movements was repeated 25 times. The variables were: time from target illumination until the cursor left the central square (onset time; OT), accuracy (path length), and movement speed. OT reduced with training (p  0.1). We quantified learning as the OT difference between the end of training and a random sequence; this was smaller for stroke survivors than controls (p = 0.015). Stroke survivors can learn a movement sequence with their paretic arm, but demonstrate impairments in sequence specific learning. Implications for Rehabilitation Motor sequence learning is important for recovery of movement after stroke. Stroke survivors were found to be capable of learning a movement sequence with their paretic arm, supporting the concept of repetitive task training for recovery of movement. Stroke survivors showed impaired sequence specific learning in comparison with age-matched controls, indicating that they may need more repetitions of a sequence in order to re-learn movements. Further research is required into the effect of lesion location, time since stroke, hand dominance and gender on learning of motor sequences after stroke.

  18. Therapeutic Robotics: A Technology Push: Stroke rehabilitation is being aided by robots that guide movement of shoulders and elbows, wrists, hands, arms and ankles to significantly improve recovery of patients.

    Science.gov (United States)

    Krebs, Hermano Igo; Hogan, Neville

    2006-09-01

    In this paper, we present a retrospective and chronological review of our efforts to revolutionize the way physical medicine is practiced by developing and deploying therapeutic robots. We present a sample of our clinical results with well over 300 stroke patients, both inpatients and outpatients, proving that movement therapy has a measurable and significant impact on recovery following brain injury. Bolstered by this result, we embarked on a two-pronged approach: 1) to determine what constitutes best therapy practice and 2) to develop additional therapeutic robots. We review our robots developed over the past 15 years and their unique characteristics. All are configured both to deliver reproducible therapy but also to measure outcomes with minimal encumbrance, thus providing critical measurement tools to help unravel the key question posed under the first prong: what constitutes "best practice"? We believe that a "gym" of robots like these will become a central feature of physical medicine and the rehabilitation clinic within the next ten years.

  19. Evolution of robotic arms

    OpenAIRE

    Moran, Michael E.

    2007-01-01

    The foundation of surgical robotics is in the development of the robotic arm. This is a thorough review of the literature on the nature and development of this device with emphasis on surgical applications. We have reviewed the published literature and classified robotic arms by their application: show, industrial application, medical application, etc. There is a definite trend in the manufacture of robotic arms toward more dextrous devices, more degrees-of-freedom, and capabilities beyond th...

  20. MiniSAR composite gimbal arm development.

    Energy Technology Data Exchange (ETDEWEB)

    Klarer, Paul Richard; Winscott, Mark (Orion International, Albuquerque, NM)

    2005-01-01

    An exploratory effort in the application of carbon epoxy composite structural materials to a multi-axis gimbal arm design is described. An existing design in aluminum was used as a baseline for a functionally equivalent redesigned outer gimbal arm using a carbon epoxy composite material. The existing arm was analyzed using finite element techniques to characterize performance in terms of strength, stiffness, and weight. A new design was virtually prototyped. using the same tools to produce a design with similar stiffness and strength, but reduced overall weight, than the original arm. The new design was prototyped using Rapid Prototyping technology, which was subsequently used to produce molds for fabricating the carbon epoxy composite parts. The design tools, process, and results are discussed.

  1. Human mimetic forearm mechanism towards bionic arm.

    Science.gov (United States)

    Seo, Minsang; Kim, Hogyun; Choi, Youngjin

    2017-07-01

    The paper presents a mechanical forearm mechanism to extend the pronation and supination (P/S) movement of the trans-radial amputee when he/she is able to conduct the P/S motion partially with his/her remaining forearm. The P/S motions of the existing prostheses and robotic arms developed till now are completely different from those of the human. When we are to develop the robotic prostheses for the amputees, two important issues should be considered such as cosmetic issue to look like normal arm and motion harmony issue between robotic prosthesis and the amputated living arm. Most prostheses do not realize the human-like P/S motion, but the simple rotational motion at the wrist by using the electric motor. In this paper, the well-known spatial four-bar mechanism is adopted in order to mimic human P/S motion as if the person does, because it is one of the best candidates to describe actual human forearm movement. To obtain the design parameters of the mechanism, first, 3D data of the amputated arm as well as the opposite side non-amputated arm are captured by using MRI (Magnetic Resonance Imaging) and 3D scanner. The design parameters such as link lengths, joint locations, and volumetric shape are determined from the measured data. Second, mathematical analysis is performed to simulate one degree-of-freedom P/S motion realized from the spatial four-bar mechanism, and the simulation results are suggested to confirm whether or not it acts like the relative movement between human ulnar and radius bones. Finally the effectiveness of the proposed mechanism is verified through two ADL (activities of daily living) tests.

  2. ARM Mentor Selection Process

    Energy Technology Data Exchange (ETDEWEB)

    Sisterson, D. L. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-10-01

    The Atmospheric Radiation Measurement (ARM) Program was created in 1989 with funding from the U.S. Department of Energy (DOE) to develop several highly instrumented ground stations to study cloud formation processes and their influence on radiative transfer. In 2003, the ARM Program became a national scientific user facility, known as the ARM Climate Research Facility. This scientific infrastructure provides for fixed sites, mobile facilities, an aerial facility, and a data archive available for use by scientists worldwide through the ARM Climate Research Facility—a scientific user facility. The ARM Climate Research Facility currently operates more than 300 instrument systems that provide ground-based observations of the atmospheric column. To keep ARM at the forefront of climate observations, the ARM infrastructure depends heavily on instrument scientists and engineers, also known as lead mentors. Lead mentors must have an excellent understanding of in situ and remote-sensing instrumentation theory and operation and have comprehensive knowledge of critical scale-dependent atmospheric processes. They must also possess the technical and analytical skills to develop new data retrievals that provide innovative approaches for creating research-quality data sets. The ARM Climate Research Facility is seeking the best overall qualified candidate who can fulfill lead mentor requirements in a timely manner.

  3. Disruption of coordination between arm, trunk, and center of pressure displacement in patients with hemiparesis.

    Science.gov (United States)

    Ustinova, Ksenia I; Goussev, Valery M; Balasubramaniam, Ramesh; Leven, Mindy F

    2004-04-01

    To determine how arm movements influence postural sway in the upright position after stroke, interactions between arm, trunk, and center of pressure (CoP) displacements in the sagittal direction were investigated in participants with hemiparesis and healthy subjects. Participants swung both arms sagittally in either of 2 directions (in-phase, anti-phase) and at 2 speeds (preferred, fast) while standing on separate force plates. Variables measured included amplitude and frequency of arm swinging, shoulder and trunk range of motion, CoP displacements under each foot and of the whole body, and the relationships between the arm, trunk, and CoP displacements. CoP displacements under the non-paretic leg were greater than those under the paretic leg, which may in part be related to the larger amplitude of swinging of the non-paretic arm. CoP displacements under each foot were not related to arm swinging during in-phase swinging at the preferred speed in healthy subjects. When speed of arm swinging was increased, however, the CoP moved in a direction opposite to the arm movement. In contrast, in individuals with hemiparesis, CoPs and arms moved in the same direction for both speeds. During anti-phase swinging in healthy subjects, the trunk counterbalanced the arm movements, while in participants with hemiparesis, the trunk moved with the affected arm. Results show that stroke resulted in abnormal patterns of arm-trunk-CoP interactions that may be related to a greater involvement of the trunk in arm transport, an altered pattern of coordination between arm and CoP displacements, and an impaired ability of the damaged nervous system to adapt postural synergies to changes in movement velocity.

  4. Separating timing, movement conditions and individual differences in the analysis of human movement

    DEFF Research Database (Denmark)

    Raket, Lars Lau; Grimme, Britta; Schöner, Gregor

    2016-01-01

    A central task in the analysis of human movement behavior is to determine systematic patterns and differences across experimental conditions, participants and repetitions. This is possible because human movement is highly regular, being constrained by invariance principles. Movement timing...... in data. The model is applied to analyze experimental data of human arm movements in which participants move a hand-held object to a target location while avoiding an obstacle. The model is used to classify movement data according to participant. Comparison to alternative approaches establishes nonlinear...... of movement variation and to test hypotheses about the effect of obstacle placement and height on the movement path. We demonstrate that the approach can be used to uncover new properties of human movement....

  5. Do movement deviations influence self-esteem and sense of coherence in mild unilateral cerebral palsy?

    Science.gov (United States)

    Riad, Jacques; Broström, Eva; Langius-Eklöf, Ann

    2013-01-01

    Individuals with unilateral cerebral palsy (CP) are often physically high functioning. Despite the mildness of the impairment, the movement deviations during walking are often noticeably deviant. In the arm, increased muscle tone causes posturing and decreased motion. In the lower extremity, gait deviations mainly involve the foot and ankle. The deviations often become more apparent with transitions between movements and during rapid movement but also when the person is emotionally affected. Arm posturing and gait deviations may be perceived as cosmetic and social impediments when the individual enters adolescence and becomes more self-conscious. The aim was to study the influence of movement deviations in the upper and lower extremity during walking, on self-esteem, and sense of coherence (SOC) in teenagers and young adults with mild unilateral CP. Three-dimensional gait analysis was performed with an 8-camera system. Movement deviations of the lower extremity, the Gait Profile Score (GPS) and of the upper extremity, and the Arm Posturing Score (APS) were calculated. Self-reported questionnaires "I think I am" measuring self-esteem and SOC were used. Forty-four patients with a mean age of 17.6 years (range, 13.0 to 24.0 y), 22 females and 22 males, and 15 sex-matched and age-matched controls participated in the study. Forty-two patients were classified as Gross motor function classification scale (GMFCS) I and 2 as GMFCS II. Patients were rated with lower self-esteem than controls (mean, 63.4 vs. 84.7; P=0.025). The SOC assessments revealed no difference. The GPS and APS was higher in patients (6.9 vs. 4.1; Pself-esteem (coefficient -0.397; P=0.001) and SOC (coefficient -0.375; P=0.05). No correlations were found with the GPS. Although physically high functioning, movement deviations in teenagers and young adults with mild unilateral CP are correlated with lower self-esteem. This is more pronounced with increased arm movement deviation and should be considered

  6. Physiologically Relevant Prosthetic Limb Movement Feedback for Upper and Lower Extremity Amputees

    Science.gov (United States)

    2016-10-01

    kinesthesia) is important to the use of our arms and legs yet this sense is completely absent amputees who must monitor all use of their prosthesis visually...required to evaluate lower limb prosthesis function. Each module includes standing or walking condition sets and perturbations allowing access to...upper arm (elbow movement), Upper leg (knee movement) and lower leg (ankle movement) to provide a physiologically relevant sense of limb movement

  7. Interaction between the long-latency stretch reflex and voluntary electromyographic activity prior to a rapid voluntary motor reaction.

    Science.gov (United States)

    Day, B L; Rothwell, J C; Marsden, C D

    1983-06-27

    The size of the long-latency component of the stretch reflex has been examined in the time interval between a signal to move and the required rapid voluntary contraction of triceps and flexor pollicis longus in 8 normal subjects. Bilateral movements of the elbow and thumb were made following an auditory signal. In 50% of the trials a torque pulse was applied unilaterally in order to elicit a stretch reflex response in one arm. The voluntary response in the contralateral arm was uncorrupted by a stretch reflex response, so was used as an indicator of voluntary reaction time. Control experiments, using an electrical stimulus to the fingers rather than muscle stretch, verified that both arms reacted almost simultaneously to the auditory cue, even when the reaction time was shortened by the presence of a unilateral electrical stimulus. Similarly, an interposed muscle stretch stimulus considerably reduced the reaction time to the audio signal. Because of this, the start of the voluntary EMG response frequently 'over-lapped' the end of the long-latency stretch reflex. Failure to take this shortening of voluntary reaction time into consideration can lead to the erroneous conclusion that reflex gain is increased prior to a rapid movement. If the 'overlap' of EMG responses is accounted for, very little change in the size of the long-latency stretch reflex is evident prior to activation of the muscles responsible for the movement of either the elbow or the thumb.

  8. Mixed Movements

    DEFF Research Database (Denmark)

    Brabrand, Helle

    2010-01-01

    levels than those related to building, and this exploration is a special challenge and competence implicit artistic development work. The project Mixed Movements generates drawing-material, not primary as representation, but as a performance-based media, making the body being-in-the-media felt and appear......Mixed Movements is a research project engaged in performance-based architectural drawing. Architectonic implementation questions relations between the human body and a body of architecture by the different ways we handle drawing materials. A drawing may explore architectonic problems at other...

  9. Practical application with plc in manipulation of a robotic arm

    Directory of Open Access Journals (Sweden)

    Cristian Barz

    2014-12-01

    Full Text Available This paper presents the use of a robotic arm PLC Siemens in order not using CNC commands. This is done by programming the PLC ladder diagram language that makes movement on the three axes of the arm by means of stepper motors. Required command console PLC is built with the help of a touch screen HMI Weintek. In the user interface are introduced distances and displacement speeds on the three axes.

  10. Arms Trafficking and Colombia

    Science.gov (United States)

    2003-01-01

    Brasil , February 20, 2001. 20 Arms Trafficking and Colombia chased, when and how they were transferred to the guerrillas or paramilitaries, or through...Mercado Blanco De Armas,” 1999, p. 44. 31Franco, Ilimar, “Pf to Block Farc Supply Routes in Amazon,” Jornal do Brasil , August 20, 1999. 26 Arms...minor base for illegal arms trafficking flights to Colombia. Planes fly from Panama into El Banco , Magdalena, or Acandí, Chocó.81 Weapons are then

  11. Nonspecific Arm Pain

    Directory of Open Access Journals (Sweden)

    Ali Moradi

    2013-12-01

    Full Text Available   Nonspecific activity-related arm pain is characterized by an absence of objective physical findings and symptoms that do not correspond with objective pathophysiology. Arm pain without strict diagnosis is often related to activity, work-related activity in particular, and is often seen in patients with physically demanding work. Psychological factors such as catastrophic thinking, symptoms of depression, and heightened illness concern determine a substantial percentage of the disability associated with puzzling hand and arm pains. Ergonomic modifications can help to control symptoms, but optimal health may require collaborative management incorporating psychosocial and psychological elements of illness.

  12. Nonspecific Arm Pain

    Directory of Open Access Journals (Sweden)

    Ali Moradi

    2013-12-01

    Full Text Available Nonspecific activity-related arm pain is characterized by an absence of objective physical findings and symptoms that do not correspond with objective pathophysiology. Arm pain without strict diagnosis is often related to activity, work-related activity in particular, and is often seen in patients with physically demanding work. Psychological factors such as catastrophic thinking, symptoms of depression, and heightened illness concern determine a substantial percentage of the disability associated with puzzling hand and arm pains. Ergonomic modifications can help to control symptoms, but optimal health may require collaborative management incorporating psychosocial and psychological elements of illness.

  13. MVACS Robotic Arm

    Science.gov (United States)

    Bonitz, R.; Slostad, J.; Bon, B.; Braun, D.; Brill, R.; Buck, C.; Fleischner, R.; Haldeman, A.; Herman, J.; Hertzel, M.; hide

    2000-01-01

    The primary purpose of the Mars Volatiles and Climate Surveyor (MVACS) Robotic Arm is to support to the other MVACS science instruments by digging trenches in the Martian soil; acquiring and dumping soil samples into the thermal evolved gas analyzer (TEGA); positioning the Soil Temperature Probe (STP) in the soil: positioning the Robotic Arm Air Temperature Sensor (RAATS) at various heights above the surface, and positioning the Robotic Arm Camera (RAC) for taking images of the surface, trench, soil samples, magnetic targets and other objects of scientific interest within its workspace.

  14. The quest for the bionic arm.

    Science.gov (United States)

    Hutchinson, Douglas T

    2014-06-01

    The current state of research of upper extremity prosthetic devices is focused on creating a complete prosthesis with full motor and sensory function that will provide amputees with a near-normal human arm. Although advances are being made rapidly, many hurdles remain to be overcome before a functional, so-called bionic arm is a reality. Acquiring signals via nerve or muscle inputs will require either a reliable wireless device or direct wiring through an osseous-integrated implant. The best way to tap into the "knowledge" present in the peripheral nerve is yet to be determined. Copyright 2014 by the American Academy of Orthopaedic Surgeons.

  15. Exemplar-based Parametric Hidden Markov Models for Recognition and Synthesis of Movements

    DEFF Research Database (Denmark)

    Herzog, Dennis; Krüger, Volker; Grest, Daniel

    2007-01-01

    A common problem in movement recognition is the recognition of movements of a particular type. E.g. pointing movements are of a particular type but differ in terms of the pointing direction. Arm movements with the goal of reaching out and grasping an object are of a particular type but differ...

  16. Biomimetics of human movement: functional or aesthetic?

    Science.gov (United States)

    Harris, Christopher M

    2009-09-01

    How should robotic or prosthetic arms be programmed to move? Copying human smooth movements is popular in synthetic systems, but what does this really achieve? We cannot address these biomimetic issues without a deep understanding of why natural movements are so stereotyped. In this article, we distinguish between 'functional' and 'aesthetic' biomimetics. Functional biomimetics requires insight into the problem that nature has solved and recognition that a similar problem exists in the synthetic system. In aesthetic biomimetics, nature is copied for its own sake and no insight is needed. We examine the popular minimum jerk (MJ) model that has often been used to generate smooth human-like point-to-point movements in synthetic arms. The MJ model was originally justified as maximizing 'smoothness'; however, it is also the limiting optimal trajectory for a wide range of cost functions for brief movements, including the minimum variance (MV) model, where smoothness is a by-product of optimizing the speed-accuracy trade-off imposed by proportional noise (PN: signal-dependent noise with the standard deviation proportional to mean). PN is unlikely to be dominant in synthetic systems, and the control objectives of natural movements (speed and accuracy) would not be optimized in synthetic systems by human-like movements. Thus, employing MJ or MV controllers in robotic arms is just aesthetic biomimetics. For prosthetic arms, the goal is aesthetic by definition, but it is still crucial to recognize that MV trajectories and PN are deeply embedded in the human motor system. Thus, PN arises at the neural level, as a recruitment strategy of motor units and probably optimizes motor neuron noise. Human reaching is under continuous adaptive control. For prosthetic devices that do not have this natural architecture, natural plasticity would drive the system towards unnatural movements. We propose that a truly neuromorphic system with parallel force generators (muscle fibres) and noisy

  17. Striking movements

    DEFF Research Database (Denmark)

    Dahl, Sofia

    2011-01-01

    Like all music performance, percussion playing requires high control over timing and sound properties. Specific to percussionists, however, is the need to adjust the movement to different instruments with varying physical properties and tactile feedback to the player. Furthermore, the well defined...

  18. Psychodynamic Movement

    DEFF Research Database (Denmark)

    Pedersen, Inge Nygaard

    2002-01-01

    This chapter/article describes the historical development of the disciplin Psychodynamic Movement. The importance of this disciplin for self-experience and for training in developing a therapist identy for the music therapy students are emphasized. Prototypeexercises developed and simplified...

  19. An overview and categorization of dynamic arm supports for people with decreased arm function.

    Science.gov (United States)

    Van der Heide, Loek A; van Ninhuijs, Bob; Bergsma, Arjen; Gelderblom, Gert Jan; van der Pijl, Dick J; de Witte, Luc P

    2014-08-01

    Assistive devices that augment arm function were already introduced during the polio era. Devices are still being developed, but a review has not been performed thus far. To create an overview and categorize assistive devices facilitating arm function in activities of daily living for people with decreased arm function. Literature review. A systematic review in three scientific literature databases. Conference proceedings, assistive technology databases, and references were searched and experts consulted. This resulted in a database of dynamic arm supports. Product information was added, and the devices were categorized. A total of 104 dynamic arm supports were found. These could be categorized as nonactuated devices (N = 39), passively actuated devices (N = 24), actively actuated devices (N = 34), or devices using the functional electrical stimulation principle (N = 7). Functionality analysis resulted in second-level categorization: tremor suppression, facilitation of anti-gravity movement, and assistance of specific joint motion. All devices could be ordered in a categorization of low complexity. Many have been developed; most have disappeared and have been succeeded by similar devices. Limitations of the devices found mainly concern interfacing and the range of motion facilitated. Future devices could make use of whatever residual strength is available in the users' arm for control. The provided overview of devices in this article and the classification developed is relevant for practitioners seeking assistive solutions for their clients as it makes the range of developed solutions both accessible and comprehensible. © The International Society for Prosthetics and Orthotics 2013.

  20. ARM for Platform Application

    Science.gov (United States)

    Patte, Mathieu; Poupat, Jean-Luc; Le Meur, Patrick

    2015-09-01

    The activities described in this paper are part of the CNES R&T “Study of a Cortex-R ARM based architecture” performed by Airbus DS Space System & Electronics in 2014. With the support of CNES, Airbus DS has performed the porting of a representative space application software on an ARM based demonstration platform. This paper presents the platform itself, the activities performed at software level and the first results on this evaluation study.

  1. Hello to Arms

    Science.gov (United States)

    2005-01-01

    This image highlights the hidden spiral arms (blue) that were discovered around the nearby galaxy NGC 4625 by the ultraviolet eyes of NASA's Galaxy Evolution Explorer. The image is composed of ultraviolet and visible-light data, from the Galaxy Evolution Explorer and the California Institute of Technology's Digitized Sky Survey, respectively. Near-ultraviolet light is colored green; far-ultraviolet light is colored blue; and optical light is colored red. As the image demonstrates, the lengthy spiral arms are nearly invisible when viewed in optical light while bright in ultraviolet. This is because they are bustling with hot, newborn stars that radiate primarily ultraviolet light. The youthful arms are also very long, stretching out to a distance four times the size of the galaxy's core. They are part of the largest ultraviolet galactic disk discovered so far. Located 31 million light-years away in the constellation Canes Venatici, NGC 4625 is the closest galaxy ever seen with such a young halo of arms. It is slightly smaller than our Milky Way, both in size and mass. However, the fact that this galaxy's disk is forming stars very actively suggests that it might evolve into a more massive and mature galaxy resembling our own. The armless companion galaxy seen below NGC 4625 is called NGC 4618. Astronomers do not know why it lacks arms but speculate that it may have triggered the development of arms in NGC 4625.

  2. Gracious Movement

    Directory of Open Access Journals (Sweden)

    Lev Kreft

    2012-07-01

    Full Text Available In 1984 Christopher Cordner offered a critical view on theories of graceful movement in sport developed by Ng. G. Wulk, David Best and Joseph Kupfer. In 2001 Paul Davis criticized his view. Cordner responded, rejecting all the criticism. More than a century before, Herbert Spencer and Jean-Marie Guyau had a similar controversy over grace. Both exchanges of opinion involve three positions: that grace is the most efficient movement and therefore something quantitative and measurable; that grace is expression of the wholeness of person and the world; and that grace is something which neither science nor philosophy can explain. To clarify these conflicting issues, this article proposes to examine the history of the notion which goes back to the Latin gratia and has root in the Ancient Greek charis, and to apply the concepts of cultural anchor and thin coherence, following John R. Searle’s explanation that we produce epistemically objective accounts of ontologically subjective reality.

  3. Role of arm motion in feet-in-place balance recovery.

    Science.gov (United States)

    Cheng, Kuangyou B; Wang, Kuan-Mao; Kuo, Shih-Yu

    2015-09-18

    Although considerable arm movements have been observed at loss of balance, research on standing balance focused primarily on the ankle and hip strategies. This study aimed to investigate the effect of arm motion on feet-in-place balance recovery. Participants stood on a single force plate and leaned forward with a straight body posture. They were then released from three forward-lean angles and regained balance without moving their forefeet under arm-swing (AS) and arm-constrained (AC) conditions. Higher success rates and shorter recovery times were found with arm motion under moderate balance perturbations. Recovery time was significantly correlated with peak linear momentum of the arms. Circumduction arm motion caused initial shoulder extension (backward arm movement) to generate reaction forces to pull the body forward, but later forward linear momentum of the arms helped move the whole body backward to avoid forward falling. However, greater lean angles increased difficulty in balance recovery, making the influences of the arms less significant. Since arm motions were observed in all participants with significantly enhanced performance under moderate balance perturbation, it was concluded that moving the arms should also be considered (together with the ankles and hips) as an effective strategy for balance recovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Epic and ARM : user's guide

    NARCIS (Netherlands)

    H.R. Walters (Pum)

    1997-01-01

    textabstractWe give a brief introduction to Epic and to ARM (they are discussed in more detail elsewhere). We show how to use the Epic compiler and how to execute ARM code. Then we describe ARM's API (application programmer's interface) which allows ARM to be used as a plug-in library. We describe

  5. Universal haptic drive: a robot for arm and wrist rehabilitation.

    Science.gov (United States)

    Oblak, Jakob; Cikajlo, Imre; Matjacić, Zlatko

    2010-06-01

    In this paper we present a universal haptic drive (UHD), a device that enables rehabilitation of either arm ("ARM" mode) or wrist ("WRIST" mode) movement in two degrees-of-freedom. The mode of training depends on the selected mechanical configuration, which depends on locking/unlocking of a passive universal joint. Actuation of the device is accomplished by utilizing a series elastic actuation principle, which enables use of off-the-shelf mechanical and actuation components. A proportional force control scheme, needed for implementation of impedance control based movement training, was implemented. The device performance in terms of achievable lower and upper bound of viable impedance range was evaluated through adequately chosen sinusoidal movement in eight directions of a planar movement for the "ARM" mode and in eight directions of a combined wrist flexion/extension and forearm pronation/supination movement for the "WRIST" mode. Additionally, suitability of the universal haptic drive for movement training was tested in a series of training sessions conducted with a chronic stroke subject. The results have shown that reliable and repeatable performance can be achieved in both modes of operation for all tested directions.

  6. Armed conflict and child health.

    Science.gov (United States)

    Rieder, Michael; Choonara, Imti

    2012-01-01

    Armed conflict has a major impact on child health throughout the world. One in six children worldwide lives in an area of armed conflict and civilians are more likely to die than soldiers as a result of the conflict. In stark contrast to the effect on children, the international arms trade results in huge profits for the large corporations involved in producing arms, weapons and munitions. Armed conflict is not inevitable but is an important health issue that should be prevented.

  7. Computational movement analysis

    CERN Document Server

    Laube, Patrick

    2014-01-01

    This SpringerBrief discusses the characteristics of spatiotemporal movement data, including uncertainty and scale. It investigates three core aspects of Computational Movement Analysis: Conceptual modeling of movement and movement spaces, spatiotemporal analysis methods aiming at a better understanding of movement processes (with a focus on data mining for movement patterns), and using decentralized spatial computing methods in movement analysis. The author presents Computational Movement Analysis as an interdisciplinary umbrella for analyzing movement processes with methods from a range of fi

  8. Mystery Spiral Arms Explained?

    Science.gov (United States)

    2007-04-01

    Using a quartet of space observatories, University of Maryland astronomers may have cracked a 45-year mystery surrounding two ghostly spiral arms in the galaxy M106. The Maryland team, led by Yuxuan Yang, took advantage of the unique capabilities of NASA's Chandra X-ray Observatory, NASA's Spitzer Space Telescope, the European Space Agency's XMM-Newton X-ray observatory, and data obtained almost a decade ago with NASA's Hubble Space Telescope. NGC X-ray Image NGC 4258 X-ray Image M106 (also known as NGC 4258) is a stately spiral galaxy 23.5 million light-years away in the constellation Canes Venatici. In visible-light images, two prominent arms emanate from the bright nucleus and spiral outward. These arms are dominated by young, bright stars, which light up the gas within the arms. "But in radio and X-ray images, two additional spiral arms dominate the picture, appearing as ghostly apparitions between the main arms," says team member Andrew Wilson of the University of Maryland. These so-called "anomalous arms" consist mostly of gas. "The nature of these anomalous arms is a long-standing puzzle in astronomy," says Yang. "They have been a mystery since they were first discovered in the early 1960s." By analyzing data from XMM-Newton, Spitzer, and Chandra, Yang, Bo Li, Wilson, and Christopher Reynolds, all at the University of Maryland at College Park, have confirmed earlier suspicions that the ghostly arms represent regions of gas that are being violently heated by shock waves. Previously, some astronomers had suggested that the anomalous arms are jets of particles being ejected by a supermassive black hole in M106's nucleus. But radio observations by the National Radio Astronomy Observatory's Very Long Baseline Array, and the Very Large Array in New Mexico, later identified another pair of jets originating in the core. "It is highly unlikely that an active galactic nucleus could have more than one pair of jets," says Yang. In 2001, Wilson, Yang, and Gerald Cecil

  9. Pest Movement

    Directory of Open Access Journals (Sweden)

    Rod Bhar

    1998-12-01

    Full Text Available Maintenance of woody borders surrounding crop fields is desirable for biodiversity conservation. However, for crop pest management, the desirability of woody borders depends on the trade-off between their effects at the local field scale and the landscape scale. At the local scale, woody borders can reduce pest populations by increasing predation rates, but they can also increase pest populations by providing complementary habitats and reducing movement rate of pests out of crop fields. At the regional scale, woody borders can reduce pest populations by reducing colonization of newly planted crop fields. Our objective was to develop guidelines for maximizing pest control while maintaining woody borders in the landscape. We wished to determine the conditions under which the regional effect of borders on colonization can outweigh local enhancement effects of borders on pest populations. We built a stochastic, individual-based, spatially implicit simulation model of a specialist insect population in a landscape divided into a number of crop fields. We conducted simulations to determine the conditions under which woody borders enhance vs. reduce the regional pest population size. The following factors were considered: landscape fragmentation, crop rotation period, barrier effect of woody borders, disperser success rate, and effect of woody borders on local survival. The simulation results suggest that woody borders are most likely to enhance regional control of crop pests if (1 the woody borders are very effective in reducing insect movement from one crop field to another, and (2 crop rotation is on a very short cycle. Based on these results, our preliminary recommendations are that woody borders should contain dense, tall vegetation to reduce insect movement, and crops should be rotated on as short a cycle as possible. These conditions should ensure that woody borders can be maintained for their conservation value without enhancing crop pest

  10. Rewards-driven control of robot arm by decoding EEG signals.

    Science.gov (United States)

    Tanwani, Ajay Kumar; del R Millan, Jose; Billard, Aude

    2014-01-01

    Decoding the user intention from non-invasive EEG signals is a challenging problem. In this paper, we study the feasibility of predicting the goal for controlling the robot arm in self-paced reaching movements, i.e., spontaneous movements that do not require an external cue. Our proposed system continuously estimates the goal throughout a trial starting before the movement onset by online classification and generates optimal trajectories for driving the robot arm to the estimated goal. Experiments using EEG signals of one healthy subject (right arm) yield smooth reaching movements of the simulated 7 degrees of freedom KUKA robot arm in planar center-out reaching task with approximately 80% accuracy of reaching the actual goal.

  11. Recognition and Synthesis of Human Movements by Parametric HMMs

    DEFF Research Database (Denmark)

    Herzog, Dennis; Krüger, Volker

    2009-01-01

    on the recognition and synthesis of human arm movements. Furthermore, we will show in various experiments the use of PHMMs for the control of a humanoid robot by synthesizing movements for relocating objects at arbitrary positions. In vision-based interaction experiments, PHMM are used for the recognition...

  12. Mechanical Power Flow Changes during Multijoint Movement Acquisition

    Science.gov (United States)

    Kadota, Koji; Matsuo, Tomoyuki; Hashizume, Ken; Tezuka, Kazushi

    2006-01-01

    We investigated the differences in mechanical power flow in early and late practice stages during a cyclic movement consisting of upper arm circumduction to clarify the change in mechanical energy use with skill acquisition. Seven participants practiced the task every other day until their joint angular movements conformed to those of an expert.…

  13. Robotic Arm Unwrapped

    Science.gov (United States)

    2008-01-01

    This image, taken shortly after NASA's Phoenix Mars Lander touched down on the surface of Mars, shows the spacecraft's robotic arm in its stowed configuration, with its biobarrier successfully unpeeled. The 'elbow' of the arm can be seen at the top center of the picture, and the biobarrier is the shiny film seen to the left of the arm. The biobarrier is an extra precautionary measure for protecting Mars from contamination with any bacteria from Earth. While the whole spacecraft was decontaminated through cleaning, filters and heat, the robotic arm was given additional protection because it is the only spacecraft part that will directly touch the ice below the surface of Mars. Before the arm was heated, it was sealed in the biobarrier, which is made of a trademarked film called Tedlar that holds up to baking like a turkey-basting bag. This ensures that any new bacterial spores that might have appeared during the final steps before launch and during the journey to Mars will not contact the robotic arm. After Phoenix landed, springs were used to pop back the barrier, giving it room to deploy. The base of the lander's Meteorological Station can be seen in this picture on the upper left. Because only the base of the station is showing, this image tells engineers that the instrument deployed successfully. The image was taken on landing day, May 25, 2008, by the spacecraft's Surface Stereo Imager. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  14. Temporal alignment of electrocorticographic recordings for upper limb movement

    Directory of Open Access Journals (Sweden)

    Omid eTalakoub

    2015-01-01

    Full Text Available The detection of movement-related components of the brain activity is useful in the design of brain machine interfaces. A common approach is to classify the brain activity into a number of templates or states. To find these templates, the neural responses are averaged over each movement task. For averaging to be effective, one must assume that the neural components occur at identical times over repeated trials. However, complex arm movements such as reaching and grasping are prone to cross-trial variability due to the way movements are performed. Typically initiation time, duration of movement and movement speed are variable even as a subject tries to reproduce the same task identically across trials. Therefore, movement-related neural activity will tend to occur at different times across each trial. Due to this mismatch, the averaging of neural activity will not bring into salience movement-related components. To address this problem, we present a method of alignment that accounts for the variabilities in the way the movements are conducted. In this study, arm speed was used to align neural activity. Four subjects had electrocorticographic (ECoG electrodes implanted over their primary motor cortex and were asked to perform reaching and retrieving tasks using the upper limb contralateral to the site of electrode implantation. The arm speeds were aligned using a nonlinear transformation of the temporal axes resulting in averaged spectrograms with superior visualization of movement-related neural activity when compared to averaging without alignment.

  15. Eye movements may cause motor contagion effects.

    Science.gov (United States)

    Constable, Merryn D; de Grosbois, John; Lung, Tiffany; Tremblay, Luc; Pratt, Jay; Welsh, Timothy N

    2017-06-01

    When a person executes a movement, the movement is more errorful while observing another person's actions that are incongruent rather than congruent with the executed action. This effect is known as "motor contagion". Accounts of this effect are often grounded in simulation mechanisms: increased movement error emerges because the motor codes associated with observed actions compete with motor codes of the goal action. It is also possible, however, that the increased movement error is linked to eye movements that are executed simultaneously with the hand movement because oculomotor and manual-motor systems are highly interconnected. In the present study, participants performed a motor contagion task in which they executed horizontal arm movements while observing a model making either vertical (incongruent) or horizontal (congruent) movements under three conditions: no instruction, maintain central fixation, or track the model's hand with the eyes. A significant motor contagion-like effect was only found in the 'track' condition. Thus, 'motor contagion' in the present task may be an artifact of simultaneously executed incongruent eye movements. These data are discussed in the context of stimulation and associative learning theories, and raise eye movements as a critical methodological consideration for future work on motor contagion.

  16. Closing a Large Maxillary Median Diastema using Bapat Power Arm

    Science.gov (United States)

    Singh, Chanchal; Bandejiya, Prashant

    2017-01-01

    Aim The aim of this study is to present a case of large maxillary median diastema closed by bodily movement of central incisors using Bapat power arm (BPA). Materials and methods After extraction of mesiodens, a power chain with a force of 120 gm was applied to BPA ligated to preadjusted edgewise brackets bonded to maxillary central incisors to move them over round steel wire for closure of resultant diastema. Bonded retainer was placed after the closure of median diastema. Results The median diastema was completely closed in 5 months period with almost bodily movement of incisors, which was confirmed by periapical X-ray. Conclusion Bapat power arm was efficient in closing diastema without any discomfort or injury and was well accepted by the patient. How to cite this article Bapat SM, Singh C, Bandejiya P. Closing a Large Maxillary Median Diastema using Bapat Power Arm. Int J Clin Pediatr Dent 2017;10(2):201-204. PMID:28890624

  17. Closing a Large Maxillary Median Diastema using Bapat Power Arm.

    Science.gov (United States)

    M Bapat, Shirish; Singh, Chanchal; Bandejiya, Prashant

    2017-01-01

    The aim of this study is to present a case of large maxillary median diastema closed by bodily movement of central incisors using Bapat power arm (BPA). After extraction of mesiodens, a power chain with a force of 120 gm was applied to BPA ligated to preadjusted edgewise brackets bonded to maxillary central incisors to move them over round steel wire for closure of resultant diastema. Bonded retainer was placed after the closure of median diastema. The median diastema was completely closed in 5 months period with almost bodily movement of incisors, which was confirmed by periapical X-ray. Bapat power arm was efficient in closing diastema without any discomfort or injury and was well accepted by the patient. Bapat SM, Singh C, Bandejiya P. Closing a Large Maxillary Median Diastema using Bapat Power Arm. Int J Clin Pediatr Dent 2017;10(2):201-204.

  18. Kinematic rules for upper and lower arm contributions to grasp orientation

    NARCIS (Netherlands)

    Marotta, J.J.; Medendorp, W.P.; Crawford, J.D.

    2003-01-01

    The purpose of the current study was to investigate the contribution of upper and lower arm torsion to grasp orientation during a reaching and grasping movement. In particular, we examined how the visuomotor system deals with the conflicting demands of coordinating upper and lower arm torsion and

  19. Kinematics design and human motion transfer for a humanoid service robot arm

    CSIR Research Space (South Africa)

    Dube, C

    2009-11-01

    Full Text Available (DOF) humanoid arm which has a two DOF shoulder girdle and has a four DOF glenohumeral joint is presented. A method of obtaining the sternum position, which forms the movement reference frame for the ten DOF arm, is formulated from human motion capture...

  20. Talking to armed groups

    Directory of Open Access Journals (Sweden)

    Olivier Bangerter

    2011-03-01

    Full Text Available To persuade fighters to respect the rules of warfare, one must understand why violations occur, how armed groups operate, what can be done to prevent violations and how to engage in dialogue with these groups. This article reflects the ICRC’s many years of experience in this area....

  1. Robotic Arm End Effector

    Science.gov (United States)

    2008-01-01

    Image illustrates the tools on the end of the arm that are used to acquire samples, image the contents of the scoop, and perform science experiments. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  2. JPRS Report, Arms Control

    Science.gov (United States)

    1989-02-22

    M. Vacek; Bratislava Radio 31 Jan] 1 Chief of Staffs Press Conference Details Planned Troop, Arms Cuts [V. Palan , et ai; RUDE PRAVO 1 Feb] 2...PRAVO in Czech on 1 February on page 1 carries a 1,500-word report by its correspondents Vladimir Palan , Stanislav Stibor, and Josef Vlcek entitled

  3. Telerobotics with whole arm collision avoidance

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelmsen, K.; Strenn, S.

    1993-09-01

    The complexity of teleorbotic operations in a cluttered environment is exacerbated by the need to present collision information to the operator in an understandable fashion. In addition to preventing movements which will cause collisions, a system providing some form of virtual force reflection (VFR) is desirable. With this goal in mind, Lawrence Livermore National Laboratory (LLNL) has installed a kinematically master/slave system and developed a whole arm collision avoidance system which interacts directly with the telerobotic controller. LLNL has also provided a structure to allow for automated upgrades of workcell models and provide collision avoidance even in a dynamically changing workcell.

  4. Central command increases muscular oxygenation of the non-exercising arm at the early period of voluntary one-armed cranking.

    Science.gov (United States)

    Ishii, Kei; Matsukawa, Kanji; Asahara, Ryota; Liang, Nan; Endo, Kana; Idesako, Mitsuhiro; Michioka, Kensuke; Sasaki, Yu; Hamada, Hironobu; Yamashita, Kaori; Watanabe, Tae; Kataoka, Tsuyoshi; Takahashi, Makoto

    2017-04-01

    This study aimed to examine whether central command increases oxygenation in non-contracting arm muscles during contralateral one-armed cranking and whether the oxygenation response caused by central command differs among skeletal muscles of the non-exercising upper limb. In 13 male subjects, the relative changes in oxygenated-hemoglobin concentration (Oxy-Hb) of the non-contracting arm muscles [the anterior deltoid, triceps brachii, biceps brachii, and extensor carpi radialis (ECR)] were measured during voluntary one-armed cranking (intensity, 35-40% of maximal voluntary effort) and mental imagery of the one-armed exercise for 1 min. Voluntary one-armed cranking increased (P arm muscles consisted of the rapid atropine-sensitive and delayed propranolol-sensitive components. Mental imagery of the exercise increased the Oxy-Hb of the arm muscles. Motor-driven passive one-armed cranking had little influence on the Oxy-Hb of the arm muscles. It is likely that central command plays a role in the initial increase in oxygenation in the non-contracting arm muscles via sympathetic cholinergic vasodilatation at the early period of one-armed cranking. The centrally induced increase in oxygenation may not be different among the distal arm muscles but may augment in the deltoid muscle. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  5. Documenting the Effects of Armed Conflict on Population Health.

    Science.gov (United States)

    Levy, Barry S; Sidel, Victor W

    2016-01-01

    War and other forms of armed conflict have profound adverse effects on population health. It is important to document these effects to inform the general public and policy makers about the consequences of armed conflict, provide services to meet the needs of affected populations, protect human rights and document violations of international humanitarian law, and help to prevent future armed conflict. Documentation can be accomplished with surveillance, epidemiological surveys, and rapid assessment. Challenges include inadequate or absent data systems, social breakdown, forced migration, reporting biases, and the fog of war. The adverse effects of the Iraq War on population health demonstrate how the effects of armed conflict on population health can be documented. We recommend the establishment of an independent mechanism, operated by the United Nations or a multilateral organization, to investigate and document the effects of armed conflict on population health.

  6. A software radio platform based on ARM and FPGA

    Directory of Open Access Journals (Sweden)

    Yang Xin.

    2016-01-01

    Full Text Available The rapid rise in computational performance offered by computer systems has greatly increased the number of practical software radio applications. A scheme presented in this paper is a software radio platform based on ARM and FPGA. FPGA works as the coprocessor together with the ARM, which serves as the core processor. ARM is used for digital signal processing and real-time data transmission, and FPGA is used for synchronous timing control and serial-parallel conversion. A SPI driver for real-time data transmission between ARM and FPGA under ARM-Linux system is provided. By adopting modular design, the software radio platform is capable of implementing wireless communication functions and satisfies the requirements of real-time signal processing platform for high security and broad applicability.

  7. Efficacy and safety of a 4-factor prothrombin complex concentrate for rapid vitamin K antagonist reversal in Japanese patients presenting with major bleeding or requiring urgent surgical or invasive procedures: a prospective, open-label, single-arm phase 3b study.

    Science.gov (United States)

    Kushimoto, Shigeki; Fukuoka, Toshio; Kimura, Akio; Toyoda, Kazunori; Brainsky, Andres; Harman, Amy; Chung, Thomas; Yasaka, Masahiro

    2017-12-01

    Rapid vitamin K antagonist (VKA) reversal is required in patients experiencing major bleeding or requiring urgent surgery. Four-factor prothrombin complex concentrate (4F-PCC; Beriplex®/Kcentra®) was shown in two large randomized controlled, international phase 3b trials to be an effective alternative to plasma for urgent VKA reversal. In the present prospective, open-label, single-arm phase 3b trial, we evaluate the efficacy and safety of 4F-PCC in Japanese patients. Eleven patients [international normalized ratio (INR) ≥2] requiring rapid VKA reversal owing to major bleeding (n = 6) or before urgent surgical/invasive procedures (n = 5) were administered 4F-PCC dosed based on INR and weight. INR reduction (≤1.3 0.5 h postinfusion; primary endpoint) was achieved in 81.8% of patients (major bleeding, 83.3%; surgical/invasive procedures, 80.0%). Effective hemostasis (main secondary endpoint) was met in 60.0% (major bleeding) and 100% (surgical/invasive procedure) of evaluable patients. Adverse events (AEs) and serious AEs were reported in 90.9 and 45.5% of patients, respectively. Two AEs were considered treatment-related; thromboembolic events rated mild and not clinically relevant by investigators. There were no deaths, fluid overload events, or viral transmission cases. Consistent with the previous results, 4F-PCC may be an effective and well-tolerated treatment for rapid VKA reversal in Japanese patients experiencing major bleeding or requiring urgent surgical/invasive procedures.

  8. Baghouse with rotating sweep arm

    Energy Technology Data Exchange (ETDEWEB)

    Noland, R.D.

    1980-11-11

    A cleaning arm for a cylindrical baghouse pivoting centrally of the clean air plenum with a cam controlled valve to provide backflushing air to successive concentric rings of filter bags with each full revolution of the cleaning arm is described.

  9. Modernization of African Armed Forces

    DEFF Research Database (Denmark)

    Mandrup, Thomas

    2015-01-01

    Concept paper framing the debate at the Dakar Forum Workshop on Modernization of Armed forces in Africa.......Concept paper framing the debate at the Dakar Forum Workshop on Modernization of Armed forces in Africa....

  10. Understanding the conventional arms trade

    Science.gov (United States)

    Stohl, Rachel

    2017-11-01

    The global conventional arms trade is worth tens of billions of dollars every year and is engaged in by every country in the world. Yet, it is often difficult to control the legal trade in conventional arms and there is a thriving illicit market, willing to arm unscrupulous regimes and nefarious non-state actors. This chapter examines the international conventional arms trade, the range of tools that have been used to control it, and challenges to these international regimes.

  11. Treatment Extension of Pegylated Interferon Alpha and Ribavirin Does Not Improve SVR in Patients with Genotypes 2/3 without Rapid Virological Response (OPTEX Trial: A Prospective, Randomized, Two-Arm, Multicentre Phase IV Clinical Trial.

    Directory of Open Access Journals (Sweden)

    Benjamin Heidrich

    Full Text Available Although sofosbuvir has been approved for patients with genotypes 2/3 (G2/3, many parts of the world still consider pegylated Interferon alpha (P and ribavirin (R as standard of care for G2/3. Patients with rapid virological response (RVR show response rates >80%. However, SVR (sustained virological response in non-RVR patients is not satisfactory. Longer treatment duration may be required but evidence from prospective trials are lacking. A total of 1006 chronic HCV genotype 2/3 patients treated with P/R were recruited into a German HepNet multicenter screening registry. Of those, only 226 patients were still HCV RNA positive at week 4 (non-RVR. Non-RVR patients with ongoing response after 24 weeks P-2b/R qualified for OPTEX, a randomized trial investigating treatment extension of additional 24 weeks (total 48 weeks, Group A or additional 12 weeks (total 36 weeks, group B of 1.5 μg/kg P-2b and 800-1400 mg R. Due to the low number of patients without RVR, the number of 150 anticipated study patients was not met and only 99 non-RVR patients (n=50 Group A, n=49 Group B could be enrolled into the OPTEX trial. Baseline factors did not differ between groups. Sixteen patients had G2 and 83 patients G3. Based on the ITT (intention-to-treat analysis, 68% [55%; 81%] in Group A and 57% [43%; 71%] in Group B achieved SVR (p= 0.31. The primary endpoint of better SVR rates in Group A compared to a historical control group (SVR 70% was not met. In conclusion, approximately 23% of G2/3 patients did not achieve RVR in a real world setting. However, subsequent recruitment in a treatment-extension study was difficult. Prolonged therapy beyond 24 weeks did not result in higher SVR compared to a historical control group.ClinicalTrials.gov NCT00803309.

  12. Robotic Arm of Rover 1

    Science.gov (United States)

    2003-01-01

    JPL engineers examine the robotic arm of Mars Exploration Rover 1. The arm is modeled after a human arm, complete with joints, and holds four devices on its end, the Rock Abrasion Tool which can grind into Martian rocks, a microscopic imager, and two spectrometers for elemental and iron-mineral identification.

  13. Worldwide Report, Arms Control.

    Science.gov (United States)

    1985-07-19

    8217 if SDI Continues (Mikhail Gorbachev; Moscow Television Service, 26 Jun 85) 48 USSR’s Ponomarev Discusses Arms Issues With Spanish Leaders (Various...sources, various dates) 51 Talks With Senate Leaders 51 Meeting With Parliament Members 53 Joint Announcement 56 Ponomarev Writes in Spanish ...mutually acceptable formula based on equality and equal security; it is as if the political idioms of the seventies have been completely forgotten. What

  14. Kiikuv maja / Anu Arm

    Index Scriptorium Estoniae

    Arm, Anu

    2006-01-01

    Eesti Kunstiakadeemia esimese kursuse arhitektuuriüliõpilaste II semestri töö. Juhendaja arhitekt Andres Alver, ehitamise Pedaspeale organiseeris suvepraktika juhendaja arhitekt Jaan Tiidemann. Autor Anu Arm, kaasa töötasid ja valmis ehitasid: Ott Alver, Maarja Elm, Mari Hunt, Alvin Järving, Marten Kaevats, Riho Kerge, Reedik Poopuu, Anu Põime, Helen Rebane, Kaisa Saarva, Martin Tago, Reet Volt. Valmis: 19. VIII 2006

  15. Movement disorders.

    Science.gov (United States)

    Stoessl, A Jon; Mckeown, Martin J

    2016-01-01

    Movement disorders can be hypokinetic (e.g., parkinsonism), hyperkinetic, or dystonic in nature and commonly arise from altered function in nuclei of the basal ganglia or their connections. As obvious structural changes are often limited, standard imaging plays less of a role than in other neurologic disorders. However, structural imaging is indicated where clinical presentation is atypical, particularly if the disorder is abrupt in onset or remains strictly unilateral. More recent advances in magnetic resonance imaging (MRI) may allow for differentiation between Parkinson's disease and atypical forms of parkinsonism. Functional imaging can assess regional cerebral blood flow (functional MRI (fMRI), positron emission tomography (PET), or single-photon emission computed tomography (SPECT)), cerebral glucose metabolism (PET), neurochemical and neuroreceptor status (PET and SPECT), and pathologic processes such as inflammation or abnormal protein deposition (PET) (Table 49.1). Cerebral blood flow can be assessed at rest, during the performance of motor or cognitive tasks, or in response to a variety of stimuli. In appropriate situations, the correct imaging modality and/or combination of modalities can be used to detect early disease or even preclinical disease, and to monitor disease progression and the effects of disease-modifying interventions. Various approaches are reviewed here. © 2016 Elsevier B.V. All rights reserved.

  16. Phoenix Robotic Arm

    Science.gov (United States)

    2007-01-01

    A vital instrument on NASA's Phoenix Mars Lander is the robotic arm, which will dig into the icy soil and bring samples back to the science deck of the spacecraft for analysis. In September 2006 at a Lockheed Martin Space Systems clean room facility near Denver, spacecraft technician Billy Jones inspects the arm during the assembly phase of the mission. Using the robotic arm -- built by the Jet Propulsion Laboratory, Pasadena -- the Phoenix mission will study the history of water and search for complex organic molecules in the ice-rich soil. The Phoenix mission is led by Principal Investigator Peter H. Smith of the University of Arizona, Tucson, with project management at NASA's Jet Propulsion Laboratory and development partnership with Lockheed Martin Space Systems. International contributions for Phoenix are provided by the Canadian Space Agency, the University of Neuchatel (Switzerland), the University of Copenhagen, and the Max Planck Institute in Germany. JPL is a division of the California Institute of Technology in Pasadena.

  17. ODYSSEUS autonomous walking robot: The leg/arm design

    Science.gov (United States)

    Bourbakis, N. G.; Maas, M.; Tascillo, A.; Vandewinckel, C.

    1994-01-01

    ODYSSEUS is an autonomous walking robot, which makes use of three wheels and three legs for its movement in the free navigation space. More specifically, it makes use of its autonomous wheels to move around in an environment where the surface is smooth and not uneven. However, in the case that there are small height obstacles, stairs, or small height unevenness in the navigation environment, the robot makes use of both wheels and legs to travel efficiently. In this paper we present the detailed hardware design and the simulated behavior of the extended leg/arm part of the robot, since it plays a very significant role in the robot actions (movements, selection of objects, etc.). In particular, the leg/arm consists of three major parts: The first part is a pipe attached to the robot base with a flexible 3-D joint. This pipe has a rotated bar as an extended part, which terminates in a 3-D flexible joint. The second part of the leg/arm is also a pipe similar to the first. The extended bar of the second part ends at a 2-D joint. The last part of the leg/arm is a clip-hand. It is used for selecting several small weight and size objects, and when it is in a 'closed' mode, it is used as a supporting part of the robot leg. The entire leg/arm part is controlled and synchronized by a microcontroller (68CH11) attached to the robot base.