WorldWideScience

Sample records for repetitive hand movements

  1. Neuronal network coherent with hand kinematics during fast repetitive hand movements.

    Science.gov (United States)

    Bourguignon, Mathieu; Jousmäki, Veikko; Op de Beeck, Marc; Van Bogaert, Patrick; Goldman, Serge; De Tiège, Xavier

    2012-01-16

    We quantified the coupling between magnetoencephalographic (MEG) cortical signals and the kinematics of fast repetitive voluntary hand movements monitored by a 3-axis accelerometer. Ten healthy right-handed adults performed self-paced flexion-extension movements of right-hand fingers at ~3Hz with either touching the thumb during flexions (TOUCH) or not (noTOUCH). At the sensor level, we found in all subjects and conditions significant coherence at the movement frequency (F0) and its first harmonic (F1). Coherence values were significantly higher in TOUCH compared to noTOUCH. At the group level, dynamic imaging of coherent sources localized the main source of coherent activity at the left primary motor (M1) hand area, except at F0 TOUCH were the main source was localized at the left primary sensory (S1) hand area. Other coherent brain areas were also identified at right S1-M1 cortices (F0), left dorsolateral prefrontal cortex (F1), left posterior parietal cortex (F0 TOUCH and F1 noTOUCH) and left medial S1-M1 areas (TOUCH). This study highlights the prominent role of rhythmic neuronal activity phase-locked to movements for the encoding and the integration of key sensori-motor features of limb kinematics. This study also suggests that somatosensory afferences play a key role to sustain a high synchronization level between the neuronal activity in coherent brain areas and hand acceleration. Some coherent brain regions differed between F0 and F1 in both conditions, suggesting that distinct cortical areas are involved in different features of hand kinematics.

  2. Risk factors for hand-wrist disorders in repetitive work

    DEFF Research Database (Denmark)

    Thomsen, J. F.; Mikkelsen, S.; Andersen, JH

    2007-01-01

    (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of questionnaires and video recordings of homogenous work tasks number of wrist movements, hand force requirements and wrist position were analysed as risk factors for hand-wrist disorders......OBJECTIVES: To identify the risk of hand-wrist disorders related to repetitive movements, use of hand force and wrist position in repetitive monotonous work. METHODS: Using questionnaires and physical examinations, the prevalence and incidence of hand-wrist pain and possible extensor tendonitis...... were less consistent. Working with the hand in a non-neutral position could not be identified as a risk factor...

  3. Bimanual-vertical hand movements.

    Science.gov (United States)

    Kwon, Jay C; Cohen, Matthew L; Williamson, John; Burtis, Brandon; Heilman, Kenneth M

    2011-07-01

    Patients often demonstrate attentional and action-intentional biases in both the transverse and coronal planes. In addition, when making forelimb movements in the transverse plane, normal participants also have spatial and magnitude asymmetries, but forelimb spatial asymmetries have not been studied in coronal space. Thus, to learn if when normal people make vertical movements they have right-left spatial and magnitude biases, seventeen healthy, blindfolded volunteers had their hands (holding pens) placed vertically in their midsagittal plane, 10 inches apart, on pieces of paper positioned above, below, and at eye-level. Participants were asked to move their hands together vertically and meet in the middle. Participants demonstrated less angular deviation in the below-eye condition than in the other spatial conditions, when moving down than up, and with their right than left hand. Movements toward eye level from upper or lower space were also more accurate than movements in the other directions. Independent of hand, lines were longer with downward than upward movements and the right hand moved more distance than the left. These attentional-intentional asymmetries may be related to gravitational force, hand-hemispheric dominance, and spatial "where" asymmetries; however, the mechanisms accounting for these asymmetries must be ascertained by future research.

  4. Practicing novel, praxis-like movements: physiological effects of repetition

    Directory of Open Access Journals (Sweden)

    Joshua Benjamin Ewen

    2016-02-01

    Full Text Available Our primary goal was to develop and validate a task that could provide evidence about how humans learn praxis gestures, such as those involving the use of tools. To that end, we created a video-based task in which subjects view a model performing novel, meaningless one-handed actions with kinematics similar to praxis gestures. Subjects then imitated the movements with their right hand. Trials were repeated 6 times to examine practice effects. EEG was recorded during the task. As a control, subjects watched videos of a model performing a well-established (over learned tool-use gesture. These gestures were also imitated 6 times. Demonstrating convergent validity, EEG measures of task-related cortical activation were similar in topography and frequency between the novel gesture task and the overlearned, praxis gesture task. As in studies assessing motor skill learning with simpler tasks, cortical activation during novel gesture learning decreased as the same gestures were repeated. In the control condition, repetition of overlearned tool-use gestures were also associated with reductions in activation, though to a lesser degree. Given that even overlearned, praxis gestures show constriction of EEG activity with repetition, it is possible that that attentional effects drive some of the repetition effects seen in EEG measures of activation during novel gesture repetition.

  5. Therapeutic benefit of repetitive transcranial magnetic stimulation for severe mirror movements A case report

    Institute of Scientific and Technical Information of China (English)

    Han Sun Kim; Sung Ho Jang; Zee-Ihn Lee; Mi Young Lee; Yun Woo Cho; Migyoung Kweon; Su Min Son

    2013-01-01

    Congenital mirror movements retard typical hand functions, but no definite therapeutic modality is available to treat such movements. We report an 8-year-old boy with severe mirror movements of both hands. His mirror movements were assessed using the Woods and Teuber grading scale and his fine motor skills were also evaluated by the Purdue Pegboard Test. A 2-week regimen of repetitive transcranial magnetic stimulation produced markedly diminished mirror movement symptoms and increased the fine motor skills of both hands. Two weeks after the completion of the regimen, mirror movement grades had improved from grade 4 to 1 in both hands and the Purdue Pegboard Test results of the right and left hands also improved from 12 to 14 or 13. These improvements were maintained for 1 month after the 2-week repetitive transcranial magnetic stimulation regimen. After 18 months, the mirror movement grade was maintained and the Purdue Pegboard test score had improved to 15 for the right hand while the left hand score was maintained at 13. This occurred without any additional repetitive transcranial magnetic stimulation or other treatment. These findings suggest that repetitive transcranial magnetic stimulation for this patient had a therapeutic and long-term effect on mirror movements.

  6. Hand Spring Operated Movement Enhancer (HandSOME): a portable, passive hand exoskeleton for stroke rehabilitation.

    Science.gov (United States)

    Brokaw, Elizabeth B; Black, Iian; Holley, Rahsaan J; Lum, Peter S

    2011-08-01

    Stroke patients often have flexor hypertonia and finger extensor weakness, which makes it difficult to open their affected hand for functional grasp. Because of this impairment, hand rehabilitation after stroke is essential for restoring functional independent lifestyles. The goal of this study is to develop a passive, lightweight, wearable device to assist with hand function during performance of activities of daily living. The device, Hand Spring Operated Movement Enhancer (HandSOME), assists with opening the patient's hand using a series of elastic cords that apply extension torques to the finger joints and compensates for the flexor hypertonia. Device design and calibration are described as well as functional and usability testing with stroke subjects with a wide range of hand impairments. In initial testing with eight stroke subjects with finger flexor hypertonia, use of the HandSOME significantly increased range of motion and functional ability (p=0.002) . There was some decrease in grip strength with the HandSOME device at the subject's ideal setting, however this was not statistically significant (p=0.167) and did not seem to have a significant effect on function. Overall HandSOME shows promise as a training tool to facilitate repetitive task practice for improving hand function in stroke patients. HandSOME can be used as part of a home-based therapy program, or as an orthotic for replacing lost function.

  7. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation

    DEFF Research Database (Denmark)

    Christensen, Mark Schram; Lundbye-Jensen, J.; Grey, M.J.;

    2010-01-01

    Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb moveme...... premotor cortex stimulation was less affected by sensory and motor deprivation than was primary motor cortex stimulation. We propose that repetitive transcranial magnetic stimulation over dorsal premotor cortex produces a corollary discharge that is perceived as movement....

  8. Stigmatization of repetitive hand use in newspaper reports of hand illness.

    Science.gov (United States)

    Anthony, Shawn; Lozano-Calderon, Santiago; Ring, David

    2008-03-01

    Failure to provide a balanced evidence-based consideration of the role of activity in illness can stigmatize individuals and their activities. We assessed the prevalence of language that stigmatized repetitive hand use and those that use their hand repetitively in newspaper coverage of common hand illnesses. The LexisNexis Academic database was used to search five major US newspapers for articles containing keywords about common hand illnesses during a 3-year period. Article language was assessed for stigmatization of activities involving repetitive hand use as well as for stigmatization of patients who use their hand repetitively. One hundred and twenty-four articles on hand illnesses were identified. Of these, 65.3% of articles stigmatized activities involving repetitive hand use, including 96.6% of articles discussing overuse injury of the hand, 90% of articles discussing tendonitis or tenosynovitis, and 51.8% of articles discussing carpal tunnel syndrome. Patient stigmatization was documented in 30.6% of the newspaper articles. Stigmatizing statements were most commonly made by journalists (94.8%), followed by patients (3.1%), and physicians (2.1%). Language that stigmatizes repetitive hand use and patients who use their hand repetitively is prevalent among US newspaper articles. Both health professionals and journalists reporting health-related news should be more sensitive to the use of stigmatizing language and provide a more balanced, measured, and evidenced-based account of hand illnesses.

  9. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation

    OpenAIRE

    Mark Schram Christensen; Jesper Lundbye-Jensen; Michael James Grey; Alexandra Damgaard Vejlby; Bo Belhage; Jens Bo Nielsen

    2010-01-01

    Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb movement and its associated somatosensory feedback. Afferent and efferent neural signalling was abolished in the arm with ischemic nerve block, and in the leg with spinal nerve block. Movement sensation was...

  10. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation.

    Directory of Open Access Journals (Sweden)

    Mark Schram Christensen

    Full Text Available Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb movement and its associated somatosensory feedback. Afferent and efferent neural signalling was abolished in the arm with ischemic nerve block, and in the leg with spinal nerve block. Movement sensation was assessed following trains of high-frequency repetitive transcranial magnetic stimulation applied over primary motor cortex, dorsal premotor cortex, and a control area (posterior parietal cortex. Magnetic stimulation over primary motor cortex and dorsal premotor cortex produced a movement sensation that was significantly greater than stimulation over the control region. Movement sensation after dorsal premotor cortex stimulation was less affected by sensory and motor deprivation than was primary motor cortex stimulation. We propose that repetitive transcranial magnetic stimulation over dorsal premotor cortex produces a corollary discharge that is perceived as movement.

  11. Sensory dysfunction associated with repetitive strain injuries of tendinitis and focal hand dystonia: a comparative study.

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    Byl, N; Wilson, F; Merzenich, M; Melnick, M; Scott, P; Oakes, A; McKenzie, A

    1996-04-01

    Repetitive strain injuries are reaching epidemic levels among workers who perform heavy schedules of rapid alternating movements (eg., computer programmers, data entry workers) or repetitive, sustained, coordinated movements (eg., editors, writers, salespeople). The purpose of this study was to determine if patients with repetitive strain injury demonstrated degraded sensory motor performance with their hands. Sixty age-matched adults were recruited, with 15 each assigned to a healthy adult control group, a healthy musician control group, a tendinitis group, or a focal dystonia group. Four sensory motor subtests from the Sensory Integration and Praxis Test were given to the subjects according to a standardized protocol. Using multiple one-factor analyses of variance in the parametric or nonparametric mode followed by post hoc pairwise testing, no significant differences were found between the healthy controls and the musician controls. On the test of kinesthesia, using the left hand, subjects with tendinitis performed significantly worse than controls and subjects with focal dystonia. Compared with controls, subjects with focal dystonia did significantly worse on graphesthesia and manual form perception (part 1 and part 2). Subjects with focal dystonia also did significantly worse than subjects with tendinitis when using the left hand on graphesthesia and manual form perception (part 2). When treating patients with repetitive strain injury, discriminative sensory motor skills must be carefully assessed and may need to be addressed as part of an effective treatment program.

  12. Lateral interception II : Predicting hand movements

    NARCIS (Netherlands)

    Michaels, CF; Jacobs, DM; Bongers, RM

    2006-01-01

    D. M. Jacobs and C. F. Michaels (2006) concluded that aspects of hand movements in lateral catching were predicted by the ratio of lateral optical velocity to expansion velocity. Their conclusions were based partly on a modified version of the required velocity model of catching (C. E. Peper, R. J.

  13. The sensory consequences of repetitive strain injury in musicians: focal dystonia of the hand.

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    Byl, N; Hamati, D; Melnick, M; Wilson, F; McKenzie, A

    1996-01-01

    Some individuals with repetitive strain injury (RSI) develop focal dystonia of the hand (FDh), a disorder of motor control manifested in a specific context during skilled, hand movements. This descriptive study was designed to determine if musicians with FDh had reduced tactile discrimination. Ten healthy adults and ten patients with FDh participated in the study. From the standardized Sensory Integration and Praxis Test, five subtests were selected to measure tactile discrimination. The Paired Wilcoxon Test was used to analyze, meaningful, planned pairwise differences by side and by group. The two groups performed similarly on the three tests measuring tactile motor perception (Finger Identification, Localization and Kinesthesia). However, those with FDh performed significantly worse than the healthy comparison group on two tactile perceptual tasks: (1) Graphesthesia, right affected (P < 0.003) and left unaffected (p < 0.005); and (2) Manual Form Perception (stereognosis) on the right affected (P < 0.002) and left unaffected (P < 0.002). It is possible that the somatosensory differences as measured by tactile discrimination tasks represent some degradation of the hand representation following prolonged, repetitive, near simultaneous sensory stimulation of adjacent digits. Tactile discrimination should be tested in patients with RSI to detect potential risks for developing FDh. Effective treatment of patients with RSI including FDh may need to target the somatosensory deficits in order to restore stress-free motor movements.

  14. Brain Representation of Active and Passive Hand Movements in Healthy Aged People

    Institute of Scientific and Technical Information of China (English)

    CAI Weisen; WU Yi; WU Junfa

    2013-01-01

    Objective:To reveal the neural network of active and passive hand movements.Method:Seven healthy aged people were checked,and acquired fimctional magnetic resonance imaging data on a 1.5T scanner.Active movement consisted of repetitive grasping and loosening of hand; passive movement involved the same movement performed by examiner.Both types of hand movements were assessed separately.These data were analysed by Statistical Parametric Mapping Microsoft.Result:The main activated brain areas were the contralateral supplemental motor area,primary motor area,primary sensory area and the ipsilateral cerebellum when subjects gripped right hands actively and passively.The supplemental area was less active in passive hand movement than active hand movement.The activated brain areas were mainly within Brodmann area 4 during active hand movement; in the contrast,the voxels triggered by passive movement were mainly within Brodmann areas 3,1,2 areas.Conclusion:The results suggest that the neural networks of passive and active tasks spared some common areas,and the passive movement could be as effective as active movement to facilitate the recovery of limbs motor function in patients with brain damage.

  15. Rotated balance in humans due to repetitive rotational movement.

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    Zakynthinaki, M S; Milla, J Madera; De Durana, A López Diaz; Martínez, C A Cordente; Romo, G Rodríguez; Quintana, M Sillero; Molinuevo, J Sampedro

    2010-03-01

    We show how asymmetries in the movement patterns during the process of regaining balance after perturbation from quiet stance can be modeled by a set of coupled vector fields for the derivative with respect to time of the angles between the resultant ground reaction forces and the vertical in the anteroposterior and mediolateral directions. In our model, which is an adaption of the model of Stirling and Zakynthinaki (2004), the critical curve, defining the set of maximum angles one can lean to and still correct to regain balance, can be rotated and skewed so as to model the effects of a repetitive training of a rotational movement pattern. For the purposes of our study a rotation and a skew matrix is applied to the critical curve of the model. We present here a linear stability analysis of the modified model, as well as a fit of the model to experimental data of two characteristic "asymmetric" elite athletes and to a "symmetric" elite athlete for comparison. The new adapted model has many uses not just in sport but also in rehabilitation, as many work place injuries are caused by excessive repetition of unaligned and rotational movement patterns.

  16. Passive hand movements disrupt adults’ counting strategies

    Directory of Open Access Journals (Sweden)

    Ineke eImbo

    2011-09-01

    Full Text Available In the present study, we experimentally tested the role of hand motor circuits in simple-arithmetic strategies. Educated adults solved simple additions (e.g., 8+3 or simple subtractions (e.g., 11–3 while they were required to retrieve the answer from long-term memory (e.g., knowing that 8+3 = 11, to transform the problem by making an intermediate step (e.g., 8+3 = 8+2+1 = 10+1 = 11 or to count one-by-one (e.g., 8+3 = 8…9…10…11. During the process of solving the arithmetic problems, the experimenter did or did not move the participants’ hand on a 4-point matrix. The results show that passive hand movements disrupted the counting strategy while leaving the other strategies unaffected. This pattern of results is in agreement with a procedural account, showing that the involvement of hand motor circuits in adults’ mathematical abilities is reminiscent of finger counting during childhood.

  17. Hand spring operated movement enhancer (HandSOME) device for hand rehabilitation after stroke.

    Science.gov (United States)

    Brokaw, Elizabeth B; Holley, Rahsaan J; Lum, Peter S

    2010-01-01

    Hand rehabilitation after stroke is essential for restoring functional independent lifestyles. After stroke, patients often have flexor hypertonia, making it difficult to open their hand for functional grasp. The development and initial testing of a passive hand rehabilitation device is discussed. The device, Hand Spring Operated Movement Enhancer (HandSOME), assists with opening the patient's hand using a series of bungee cords that apply extension torques to the finger joints that compensate for the flexor hypertonia. This results in significant increase in range of motion and functional use when wearing HandSOME, even in severely impaired subjects. Device design, calibration, and range of motion are described as well as functional and usability testing with stroke subjects.

  18. Communicative hand gestures and object-directed hand movements activated the mirror neuron system

    OpenAIRE

    Montgomery, Kimberly J.; Isenberg, Nancy; Haxby, James V.

    2007-01-01

    Humans produce hand movements to manipulate objects, but also make hand movements to convey socially relevant information to one another. The mirror neuron system (MNS) is activated during the observation and execution of actions. Previous neuroimaging experiments have identified the inferior parietal lobule (IPL) and frontal operculum as parts of the human MNS. Although experiments have suggested that object-directed hand movements drive the MNS, it is not clear whether communicative hand ge...

  19. Revisiting the relationship between hand preference and lateral eye movement

    OpenAIRE

    Indiwar Misra; Damodar Suar; Manas K. Mandal

    2010-01-01

    The study examines the relationship between hand preference and conjugate lateral eye movements. The sample comprised of 224 persons. The hand preference was assessed using a handedness inventory. Conjugate lateral eye movements were elicited in response to verbal and spatial questions among left-, mixed- and right-handers. The left- and mixed-handers exhibit significantly greater number of conjugate lateral eye movements than the right-handers. On the verbal task, right-handers exhibit right...

  20. Movement repetitions in physical and occupational therapy during spinal cord injury rehabilitation.

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    Zbogar, D; Eng, J J; Miller, W C; Krassioukov, A V; Verrier, M C

    2017-02-01

    Longitudinal observational study. To quantify the amount of upper- and lower-extremity movement repetitions (that is, voluntary movements as part of a functional task or specific motion) occurring during inpatient spinal cord injury (SCI), physical (PT) and occupational therapy (OT), and examine changes over the inpatient rehabilitation stay. Two stand-alone inpatient SCI rehabilitation centers. Participants: A total of 103 patients were recruited through consecutive admissions to SCI rehabilitation. Trained assistants observed therapy sessions and obtained clinical outcome measures in the second week following admission and in the second to last week before discharge. PT and OT time, upper- and lower-extremity repetitions and changes in these outcomes over the course of rehabilitation stay. We observed 561 PT and 347 OT sessions. Therapeutic time comprised two-thirds of total therapy time. Summed over PT and OT, the median upper-extremity repetitions in patients with paraplegia were 7 repetitions and in patients with tetraplegia, 42 repetitions. Lower-extremity repetitions and steps primarily occurred in ambulatory patients and amounted to 218 and 115, respectively (summed over PT and OT sessions at discharge). Wilcoxon-signed rank tests revealed that most repetition variables did not change significantly over the inpatient rehabilitation stay. In contrast, clinical outcomes for the arm and leg improved over this time period. Repetitions of upper- and lower-extremity movements are markedly low during PT and OT sessions. Despite improvements in clinical outcomes, there was no significant increase in movement repetitions over the course of inpatient rehabilitation stay.

  1. Alien hand syndrome: neural correlates of movements without conscious will.

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    Michael Schaefer

    Full Text Available BACKGROUND: The alien hand syndrome is a striking phenomenon characterized by purposeful and autonomous movements that are not voluntarily initiated. This study aimed to examine neural correlates of this rare neurological disorder in a patient with corticobasal degeneration and alien hand syndrome of the left hand. METHODOLOGY/PRINCIPAL FINDINGS: We employed functional magnetic resonance imaging to investigate brain responses associated with unwanted movements in a case study. Results revealed that alien hand movements involved a network of brain activations including the primary motor cortex, premotor cortex, precuneus, and right inferior frontal gyrus. Conscious and voluntary movements of the alien hand elicited a similar network of brain responses but lacked an activation of the inferior frontal gyrus. The results demonstrate that alien and unwanted movements may engage similar brain networks than voluntary movements, but also imply different functional contributions of prefrontal areas. Since the inferior frontal gyrus was uniquely activated during alien movements, the results provide further support for a specific role of this brain region in inhibitory control over involuntary motor responses. CONCLUSIONS/SIGNIFICANCE: We discuss the outcome of this study as providing evidence for a distributed neural network associated with unwanted movements in alien hand syndrome, including brain regions known to be related to movement execution and planning as well as areas that have been linked to inhibition control (inferior frontal gyrus and experience of agency (precuneus.

  2. Comparison of Sensory-motor Rhythm and Movement Related Cortical Potential during Ballistic and Repetitive Motor Imagery

    Institute of Scientific and Technical Information of China (English)

    XU Ren; JIANG Ning; MRACHACZ-KERSTING Natalie; DREMSTRUP Kim; FARINA Dario

    2014-01-01

    In this study, we compared two types of EEG modalities, sensory-motor rhythms (SMR) and movement related cortical potentials (MRCP), on four healthy subjects performing ballistic or repetitive movement imagination. The EEG waveform morphology across subjects was similar for MRCPs, whereas there was not a clear pattern for SMRs. The rank-sum test showed a significant difference between the amplitude of baseline and that of the MRCP as early as 2 s prior to imagery onset, for both types of motor imageries, indicating strong discriminative power of MRCPs for predicting movement onset. For SMR, this type of discriminative power was relatively weak and highly subject-specific. On the other hand, the SMR landscape under the two movement imagery types was distinctive, holding a potential for discriminating the two movement imagery types. These preliminary results presented different characteristics of SMR and MRCP under different motor imageries, providing valuable information regarding the design and implementation of motor imagery based on BCI system.

  3. Hand movement effects on word learning and retrieval in adults.

    Science.gov (United States)

    Ciantar, Jessica; Finch, Emma; Copland, David A

    2013-01-01

    The present study investigated the effect of performing an intentional non-meaningful hand movement on subsequent lexical acquisition and retrieval in healthy adults. Twenty-five right-handed healthy individuals were required to learn the names (2-syllable legal nonwords) for a series of unfamiliar objects. Participants also completed a familiar picture naming task to investigate the effects of the intentional non-meaningful movement on lexical retrieval. Results revealed that performing this hand movement immediately before linguistic tasks interfered with both new word learning and familiar picture naming when compared with no movement. These results extend previous findings of dual task interference effects in healthy individuals, suggesting that complex, non-meaningful, hand movements can also interfere with subsequent lexical acquisition and retrieval.

  4. Hand movement effects on word learning and retrieval in adults.

    Directory of Open Access Journals (Sweden)

    Jessica Ciantar

    Full Text Available The present study investigated the effect of performing an intentional non-meaningful hand movement on subsequent lexical acquisition and retrieval in healthy adults. Twenty-five right-handed healthy individuals were required to learn the names (2-syllable legal nonwords for a series of unfamiliar objects. Participants also completed a familiar picture naming task to investigate the effects of the intentional non-meaningful movement on lexical retrieval. Results revealed that performing this hand movement immediately before linguistic tasks interfered with both new word learning and familiar picture naming when compared with no movement. These results extend previous findings of dual task interference effects in healthy individuals, suggesting that complex, non-meaningful, hand movements can also interfere with subsequent lexical acquisition and retrieval.

  5. Hand Movement Effects on Word Learning and Retrieval in Adults

    OpenAIRE

    Jessica Ciantar; Emma Finch; David A. Copland

    2013-01-01

    The present study investigated the effect of performing an intentional non-meaningful hand movement on subsequent lexical acquisition and retrieval in healthy adults. Twenty-five right-handed healthy individuals were required to learn the names (2-syllable legal nonwords) for a series of unfamiliar objects. Participants also completed a familiar picture naming task to investigate the effects of the intentional non-meaningful movement on lexical retrieval. Results revealed that performing this...

  6. Coordinated control of eye and hand movements in dynamic reaching

    NARCIS (Netherlands)

    Neggers, S.F.W.; Bekkering, H.

    2002-01-01

    In the present study, we integrated two recent, at first sight contradictory findings regarding the question whether saccadic eye movements can be generated to a newly presented target during an ongoing hand movement. Saccades were measured during so-called adaptive and sustained pointing

  7. Coordinated control of eye and hand movements in dynamic reaching

    NARCIS (Netherlands)

    Neggers, SFW; Bekkering, H

    2002-01-01

    In the present study, we integrated two recent, at first sight contradictory findings regarding the question whether saccadic eye movements can be generated to a newly presented target during an ongoing hand movement. Saccades were measured during so-called adaptive and sustained pointing conditions

  8. Repetitive Arm Movements During Sleep: A Polysomnographic Assessment

    Science.gov (United States)

    Torabi-Nami, Mohammad; Mehrabi, Samrad; Derman, Sabri

    2016-01-01

    Sleep-related movement disorders should be differentiated from parasomnias, sleep-associated behavioral disorders, and epilepsy. Polysomnography (PSG) is the gold standard in evaluating such disorders. Periodic leg movement disorder during sleep (PLMS), hypnic jerks, bruxism, rhythmic movement disorder, restless legs syndrome, and nocturnal leg cramps have broadly been discussed in the literature. However, periodic arm movement disorder in sleep (PAMS) is a less-appreciated entity perhaps because arm surface electromyography is not an integral part of the standard polysomnography. Results from our PSG study in a case suspected for PAMS prompted us to herewith discuss this problem. PMID:27563420

  9. Cerebral reorganisation of human hand movement following dynamic immobilisation

    NARCIS (Netherlands)

    de Jong, BM; Coert, JH; Stenekes, MW; Leenders, KL; Paans, AMJ; Nicolai, JRA

    2003-01-01

    Surgical treatment of a flexor tendon lesion of the hand is followed by a 6-week period of dynamic immobilisation. This is achieved by the elastic strings of a Kleinert splint, enabling only passive and no active flexor movements. After such immobilisation, the appearance of a temporary clumsy hand

  10. Multiple sessions of low-frequency repetitive transcranial magnetic stimulation in focal hand dystonia

    DEFF Research Database (Denmark)

    Kimberley, Teresa Jacobson; Borich, Michael R; Arora, Sanjeev

    2013-01-01

    Purpose: The ability of low-frequency repetitive transcranial magnetic stimulation (rTMS) to enhance intracortical inhibition has motivated its use as a potential therapeutic intervention in focal hand dystonia (FHD). In this preliminary investigation, we assessed the physiologic and behavioral...

  11. Complex unconstrained three-dimensional hand movement and constant equi-affine speed.

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    Maoz, Uri; Berthoz, Alain; Flash, Tamar

    2009-02-01

    One long-established simplifying principle behind the large repertoire and high versatility of human hand movements is the two-thirds power law-an empirical law stating a relationship between local geometry and kinematics of human hand trajectories during planar curved movements. It was further generalized not only to various types of human movements, but also to motion perception and prediction, although it was unsuccessful in explaining unconstrained three-dimensional (3D) movements. Recently, movement obeying the power law was proved to be equivalent to moving with constant planar equi-affine speed. Generalizing such motion to 3D space-i.e., to movement at constant spatial equi-affine speed-predicts the emergence of a new power law, whose utility for describing spatial scribbling movements we have previously demonstrated. In this empirical investigation of the new power law, subjects repetitively traced six different 3D geometrical shapes with their hand. We show that the 3D power law explains the data consistently better than both the two-thirds power law and an additional power law that was previously suggested for spatial hand movements. We also found small yet systematic modifications of the power-law's exponents across the various shapes, which further scrutiny suggested to be correlated with global geometric factors of the traced shape. Nevertheless, averaging over all subjects and shapes, the power-law exponents are generally in accordance with constant spatial equi-affine speed. Taken together, our findings provide evidence for the potential role of non-Euclidean geometry in motion planning and control. Moreover, these results seem to imply a relationship between geometry and kinematics that is more complex than the simple local one stipulated by the two-thirds power law and similar models.

  12. Dissociation between neuronal activity in sensorimotor cortex and hand movement revealed as a function of movement rate.

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    Hermes, Dora; Siero, Jeroen C W; Aarnoutse, Erik J; Leijten, Frans S S; Petridou, Natalia; Ramsey, Nick F

    2012-07-11

    It is often assumed that similar behavior is generated by the same brain activity. However, this does not take into account the brain state or recent behavioral history and movement initiation or continuation may not be similarly generated in the brain. To study whether similar movements are generated by the same brain activity, we measured neuronal population activity during repeated movements. Three human subjects performed a motor repetition task in which they moved their hand at four different rates (0.3, 0.5, 1, and 2 Hz). From high-resolution electrocorticography arrays implanted on motor and sensory cortex, high-frequency power (65-95 Hz) was extracted as a measure of neuronal population activity. During the two faster movement rates, high-frequency power was significantly suppressed, whereas movement parameters remained highly similar. This suppression was nonlinear: after the initial movement, neuronal population activity was reduced most strongly, and the data fit a model in which a fast decline rapidly converged to saturation. The amplitude of the beta-band suppression did not change with different rates. However, at the faster rates, beta power did not return to baseline between movements but remained suppressed. We take these findings to indicate that the extended beta suppression at the faster rates, which may suggest a release of inhibition in motor cortex, facilitates movement initiation. These results show that the relationship between behavior and neuronal activity is not consistent: recent movement influences the state of motor cortex and facilitates next movements by reducing the required level of neuronal activity.

  13. Effects of intensive repetition of a new facilitation technique on motor functional recovery of the hemiplegic upper limb and hand

    Science.gov (United States)

    Kawahira, Kazumi; Shimodozono, Megumi; Etoh, Seiji; Kamada, Katsuya; Noma, Tomokazu; Tanaka, Nobuyuki

    2010-01-01

    Objective To study the effects on the hemiplegic upper limb of repetitive facilitation exercises (RFEs) using a novel facilitation technique, in which the patient's intention to move the hemiplegic upper limb or finger was followed by realization of the movement using multiple sensory stimulations. Methods Twenty-three stroke patients were enrolled in a cross-over study in which 2-week RFE sessions (100 repetitions each of five-to-eight types of facilitation exercise per day) were alternated with 2-week conventional rehabilitation (CR) sessions, for a total of four sessions. Treatments were begun with the 2-week RFE session in one group and the 2-week CR session in the second group. Results After the first 2-week RFE session, both groups showed improvements in the Brunnstrom stages of the upper limb and the hand, in contrast to the small improvements observed during the first CR session. The Simple Test for Evaluating Hand Function (STEF) score, which evaluates the ability of manipulating objects, in both groups improved during both sessions. After the second 2-week RFE and CR sessions, both groups showed little further improvement except in the STEF score. Conclusion The novel RFEs promoted the functional recovery of the hemiplegic upper limb and hand to a greater extent than the CR sessions. PMID:20715890

  14. Phantom hand and wrist movements in upper limb amputees are slow but naturally controlled movements.

    Science.gov (United States)

    De Graaf, J B; Jarrassé, N; Nicol, C; Touillet, A; Coyle, T; Maynard, L; Martinet, N; Paysant, J

    2016-01-15

    After limb amputation, patients often wake up with a vivid perception of the presence of the missing limb, called "phantom limb". Phantom limbs have mostly been studied with respect to pain sensation. But patients can experience many other phantom sensations, including voluntary movements. The goal of the present study was to quantify phantom movement kinematics and relate these to intact limb kinematics and to the time elapsed since amputation. Six upper arm and two forearm amputees with various delays since amputation (6months to 32years) performed phantom finger, hand and wrist movements at self-chosen comfortable velocities. The kinematics of the phantom movements was indirectly obtained via the intact limb that synchronously mimicked the phantom limb movements, using a Cyberglove® for measuring finger movements and an inertial measurement unit for wrist movements. Results show that the execution of phantom movements is perceived as "natural" but effortful. The types of phantom movements that can be performed are variable between the patients but they could all perform thumb flexion/extension and global hand opening/closure. Finger extension movements appeared to be 24% faster than finger flexion movements. Neither the number of types of phantom movements that can be executed nor the kinematic characteristics were related to the elapsed time since amputation, highlighting the persistence of post-amputation neural adaptation. We hypothesize that the perceived slowness of phantom movements is related to altered proprioceptive feedback that cannot be recalibrated by lack of visual feedback during phantom movement execution.

  15. Effect of repetition proportion on language-driven anticipatory eye movements

    Science.gov (United States)

    Britt, Allison E.; Mirman, Daniel; Kornilov, Sergey A.; Magnuson, James S.

    2014-01-01

    Previous masked priming research in word recognition has demonstrated that repetition priming is influenced by experiment-wise information structure, such as proportion of target repetition. Research using naturalistic tasks and eye-tracking has shown that people use linguistic knowledge to anticipate upcoming words. We examined whether the proportion of target repetition within an experiment can have a similar effect on anticipatory eye movements. We used a word-to-picture matching task (i.e., the visual world paradigm) with target repetition proportion carefully controlled. Participants’ eye movements were tracked starting when the pictures appeared, one second prior to the onset of the target word. Targets repeated from the previous trial were fixated more than other items during this preview period when target repetition proportion was high and less than other items when target repetition proportion was low. These results indicate that linguistic anticipation can be driven by short-term within-experiment trial structure, with implications for the generalization of priming effects, the bases of anticipatory eye movements, and experiment design. PMID:24345674

  16. The oscillatory network of simple repetitive bimanual movements.

    Science.gov (United States)

    Pollok, Bettina; Südmeyer, Martin; Gross, Joachim; Schnitzler, Alfons

    2005-09-01

    Bimanual synchronization relies on the precisely coordinated interplay of both hands. It is assumed that during temporal bimanual coordination, timing signals controlling each hand might be integrated. Although a specific role of the cerebellum for this integration process has been suggested, its neural foundations are still poorly understood. Since dynamic interactions between spatially distributed neural activity are reflected in oscillatory neural coupling, the aim of the present study was to characterize the dynamic interplay between participating brain structures. More specifically, the study aimed at investigating whether any evidence for the integration of bilateral cerebellar hemispheres could be found. Seven right-handed subjects synchronized bimanual index finger-taps to a regular pacing signal. We recorded continuous neuromagnetic activity using a 122-channel whole-head neuromagnetometer and surface EMGs of the first dorsal interosseus (FDI) muscle of both hands. Coherence analysis revealed that an oscillatory network coupling at 8-12 Hz subserves task execution. The constituents are bilateral primary sensorimotor and premotor areas, posterior-parietal and primary auditory cortex, thalamus and cerebellum. Coupling occurred at different cortical and subcortical levels within and between both hemispheres. Coupling between primary sensorimotor and premotor areas was observed directly and indirectly via the thalamus. Coupling direction suggests that information was integrated within the left premotor cortex corroborating a specific role of the left premotor cortex for motor control in right-handers. Most importantly, our data indicate strong coupling between both cerebellar hemispheres substantiating the hypothesis that cerebellar signals might be integrated during task execution.

  17. Multi-class EEG classification of voluntary hand movement directions

    Science.gov (United States)

    Robinson, Neethu; Guan, Cuntai; Vinod, A. P.; Keng Ang, Kai; Tee, Keng Peng

    2013-10-01

    Objective. Studies have shown that low frequency components of brain recordings provide information on voluntary hand movement directions. However, non-invasive techniques face more challenges compared to invasive techniques. Approach. This study presents a novel signal processing technique to extract features from non-invasive electroencephalography (EEG) recordings for classifying voluntary hand movement directions. The proposed technique comprises the regularized wavelet-common spatial pattern algorithm to extract the features, mutual information-based feature selection, and multi-class classification using the Fisher linear discriminant. EEG data from seven healthy human subjects were collected while they performed voluntary right hand center-out movement in four orthogonal directions. In this study, the movement direction dependent signal-to-noise ratio is used as a parameter to denote the effectiveness of each temporal frequency bin in the classification of movement directions. Main results. Significant (p movement direction dependent modulation in the EEG data was identified largely towards the end of movement at low frequencies (≤6 Hz) from the midline parietal and contralateral motor areas. Experimental results on single trial classification of the EEG data collected yielded an average accuracy of (80.24 ± 9.41)% in discriminating the four different directions using the proposed technique on features extracted from low frequency components. Significance. The proposed feature extraction strategy provides very high multi-class classification accuracies, and the results are proven to be more statistically significant than existing methods. The results obtained suggest the possibility of multi-directional movement classification from single-trial EEG recordings using the proposed technique in low frequency components.

  18. Visually Guided Hand Movements in Children with Minor Neurological Dysfunction: Response Time and Movement Organization.

    Science.gov (United States)

    Schellekens, J. M. H.; And Others

    1983-01-01

    Presents preliminary data on how, during the execution of visually guided hand movements, differences in response time between children with and without signs of minor neurological dysfunction may be related to differences in the spatio-temporal organization of their movements. (MP)

  19. The Effect of Comprehensive Hand Repetitive Intensive Strength Training (CHRIST) Using Motion Analysis in Children with Cerebral Palsy.

    Science.gov (United States)

    Kim, Dong-A; Lee, Jung-Ah; Hwang, Pil-Woo; Lee, Min-Jin; Kim, Hyun-Kyung; Park, Jeong-Joon; You, Joshua H; Lee, Dong-Ryul; Lee, Nam-Gi

    2012-02-01

    To investigate the effect of Comprehensive Hand Repetitive Intensive Strength Training (CHRIST) on upper limb function in children with cerebral palsy using motion analysis. The subjects in this study included 19 children (10 males, 9 females, mean age=8.8 years) with cerebral palsy. The experimental group (n=10) received CHRIST and general rehabilitation therapy. The control group (n=9) received a home program as well as general rehabilitation therapy. Both groups received 30 sessions of CHRIST or home program training for 60 minutes per session 3 times a week during the 10-week period. The reaching movements were captured by a motion analysis system. Kinematic variables including movement time (MT), mean velocity (MV), normalized jerk score (NJS), mean angular velocity (MAV) and normalized jerk score of the shoulder, elbow and wrist joint with comfortable and fast speed were analyzed between groups and the pre-post training group. After pre- and post-training experimental group, MT, MV, NJS, MAV of shoulder, elbow, wrist and NJS of elbow and wrist improved significantlyin reaching movement of both comfortable and fast speed (ptraining control group, MV improved significantlyin reaching movement of only comfortable speed (pchildren with cerebral palsy.

  20. fNIRS exhibits weak tuning to hand movement direction.

    Science.gov (United States)

    Waldert, Stephan; Tüshaus, Laura; Kaller, Christoph P; Aertsen, Ad; Mehring, Carsten

    2012-01-01

    Functional near-infrared spectroscopy (fNIRS) has become an established tool to investigate brain function and is, due to its portability and resistance to electromagnetic noise, an interesting modality for brain-machine interfaces (BMIs). BMIs have been successfully realized using the decoding of movement kinematics from intra-cortical recordings in monkey and human. Recently, it has been shown that hemodynamic brain responses as measured by fMRI are modulated by the direction of hand movements. However, quantitative data on the decoding of movement direction from hemodynamic responses is still lacking and it remains unclear whether this can be achieved with fNIRS, which records signals at a lower spatial resolution but with the advantage of being portable. Here, we recorded brain activity with fNIRS above different cortical areas while subjects performed hand movements in two different directions. We found that hemodynamic signals in contralateral sensorimotor areas vary with the direction of movements, though only weakly. Using these signals, movement direction could be inferred on a single-trial basis with an accuracy of ∼65% on average across subjects. The temporal evolution of decoding accuracy resembled that of typical hemodynamic responses observed in motor experiments. Simultaneous recordings with a head tracking system showed that head movements, at least up to some extent, do not influence the decoding of fNIRS signals. Due to the low accuracy, fNIRS is not a viable alternative for BMIs utilizing decoding of movement direction. However, due to its relative resistance to head movements, it is promising for studies investigating brain activity during motor experiments.

  1. Temporal control and hand movement efficiency in skilled music performance.

    Science.gov (United States)

    Goebl, Werner; Palmer, Caroline

    2013-01-01

    Skilled piano performance requires considerable movement control to accomplish the high levels of timing and force precision common among professional musicians, who acquire piano technique over decades of practice. Finger movement efficiency in particular is an important factor when pianists perform at very fast tempi. We document the finger movement kinematics of highly skilled pianists as they performed a five-finger melody at very fast tempi. A three-dimensional motion-capture system tracked the movements of finger joints, the hand, and the forearm of twelve pianists who performed on a digital piano at successively faster tempi (7-16 tones/s) until they decided to stop. Joint angle trajectories computed for all adjacent finger phalanges, the hand, and the forearm (wrist angle) indicated that the metacarpophalangeal joint contributed most to the vertical fingertip motion while the proximal and distal interphalangeal joints moved slightly opposite to the movement goal (finger extension). An efficiency measure of the combined finger joint angles corresponded to the temporal accuracy and precision of the pianists' performances: Pianists with more efficient keystroke movements showed higher precision in timing and force measures. Keystroke efficiency and individual joint contributions remained stable across tempo conditions. Individual differences among pianists supported the view that keystroke efficiency is required for successful fast performance.

  2. Temporal control and hand movement efficiency in skilled music performance.

    Directory of Open Access Journals (Sweden)

    Werner Goebl

    Full Text Available Skilled piano performance requires considerable movement control to accomplish the high levels of timing and force precision common among professional musicians, who acquire piano technique over decades of practice. Finger movement efficiency in particular is an important factor when pianists perform at very fast tempi. We document the finger movement kinematics of highly skilled pianists as they performed a five-finger melody at very fast tempi. A three-dimensional motion-capture system tracked the movements of finger joints, the hand, and the forearm of twelve pianists who performed on a digital piano at successively faster tempi (7-16 tones/s until they decided to stop. Joint angle trajectories computed for all adjacent finger phalanges, the hand, and the forearm (wrist angle indicated that the metacarpophalangeal joint contributed most to the vertical fingertip motion while the proximal and distal interphalangeal joints moved slightly opposite to the movement goal (finger extension. An efficiency measure of the combined finger joint angles corresponded to the temporal accuracy and precision of the pianists' performances: Pianists with more efficient keystroke movements showed higher precision in timing and force measures. Keystroke efficiency and individual joint contributions remained stable across tempo conditions. Individual differences among pianists supported the view that keystroke efficiency is required for successful fast performance.

  3. Representing tools as hand movements: early and somatotopic visuomotor transformations.

    Science.gov (United States)

    Bartoli, Eleonora; Maffongelli, Laura; Jacono, Marco; D'Ausilio, Alessandro

    2014-08-01

    The term affordance defines a property of objects, which relates to the possible interactions that an agent can carry out on that object. In monkeys, canonical neurons encode both the visual and the motor properties of objects with high specificity. However, it is not clear if in humans exists a similarly fine-grained description of these visuomotor transformations. In particular, it has not yet been proven that the processing of visual features related to specific affordances induces both specific and early visuomotor transformations, given that complete specificity has been reported to emerge quite late (300-450ms). In this study, we applied an adaptation-stimulation paradigm to investigate early cortico-spinal facilitation and hand movements׳ synergies evoked by the observation of tools. We adapted, through passive observation of finger movements, neuronal populations coding either for precision or power grip actions. We then presented the picture of one tool affording one of the two grasps types and applied single-pulse Transcranial Magnetic Stimulation (TMS) to the hand primary motor cortex, 150ms after image onset. Cortico-spinal excitability of the Abductor Digiti Minimi and Abductor Pollicis Brevis showed a detailed pattern of modulations, matching tools׳ affordances. Similarly, TMS-induced hand movements showed a pattern of grip-specific whole hand synergies. These results offer a direct proof of the emergence of an early visuomotor transformation when tools are observed, that maintains the same amount of synergistic motor details as the actions we can perform on them.

  4. Discrimination of biomechanically possible and impossible hand movements at birth.

    Science.gov (United States)

    Longhi, Elena; Senna, Irene; Bolognini, Nadia; Bulf, Hermann; Tagliabue, Paolo; Cassia, Viola Macchi; Turati, Chiara

    2015-01-01

    The development of human body perception has long been investigated, but little is known about its early origins. This study focused on how a body part highly relevant to the human species, namely the hand, is perceived a few days after birth. Using a preferential-looking paradigm, 24- to 48-hr-old newborns watched biomechanically possible and impossible dynamic hand gestures (Experiment 1, N = 15) and static hand postures (Experiment 2, N = 15). In Experiment 1, newborns looked longer at the impossible, compared to the possible, hand movement, whereas in Experiment 2 no visual preference emerged. These findings suggest that early in life the representation of the human body may be shaped by sensory-motor experience.

  5. Corticomuscular coherence analysis on hand movement distinction for active rehabilitation.

    Science.gov (United States)

    Lou, Xinxin; Xiao, Siyuan; Qi, Yu; Hu, Xiaoling; Wang, Yiwen; Zheng, Xiaoxiang

    2013-01-01

    Active rehabilitation involves patient's voluntary thoughts as the control signals of restore device to assist stroke rehabilitation. Although restoration of hand opening stands importantly in patient's daily life, it is difficult to distinguish the voluntary finger extension from thumb adduction and finger flexion using stroke patients' electroencephalography (EMG) on single muscle activity. We propose to implement corticomuscular coherence analysis on electroencephalography (EEG) and EMG signals on Extensor Digitorum to extract their intention involved in hand opening. EEG and EMG signals of 8 subjects are simultaneously collected when executing 4 hand movement tasks (finger extension, thumb adduction, finger flexion, and rest). We explore the spatial and temporal distribution of the coherence and observe statistically significant corticomuscular coherence appearing at left motor cortical area and different patterns within beta frequency range for 4 movement tasks. Linear discriminate analysis is applied on the coherence pattern to distinguish finger extension from thumb adduction, finger flexion, and rest. The classification results are greater than those by EEG only. The results indicate the possibility to detect voluntary hand opening based on coherence analysis between single muscle EMG signal and single EEG channel located in motor cortical area, which potentially helps active hand rehabilitation for stroke patients.

  6. Corticomuscular Coherence Analysis on Hand Movement Distinction for Active Rehabilitation

    Directory of Open Access Journals (Sweden)

    Xinxin Lou

    2013-01-01

    Full Text Available Active rehabilitation involves patient’s voluntary thoughts as the control signals of restore device to assist stroke rehabilitation. Although restoration of hand opening stands importantly in patient’s daily life, it is difficult to distinguish the voluntary finger extension from thumb adduction and finger flexion using stroke patients’ electroencephalography (EMG on single muscle activity. We propose to implement corticomuscular coherence analysis on electroencephalography (EEG and EMG signals on Extensor Digitorum to extract their intention involved in hand opening. EEG and EMG signals of 8 subjects are simultaneously collected when executing 4 hand movement tasks (finger extension, thumb adduction, finger flexion, and rest. We explore the spatial and temporal distribution of the coherence and observe statistically significant corticomuscular coherence appearing at left motor cortical area and different patterns within beta frequency range for 4 movement tasks. Linear discriminate analysis is applied on the coherence pattern to distinguish finger extension from thumb adduction, finger flexion, and rest. The classification results are greater than those by EEG only. The results indicate the possibility to detect voluntary hand opening based on coherence analysis between single muscle EMG signal and single EEG channel located in motor cortical area, which potentially helps active hand rehabilitation for stroke patients.

  7. Describing baseball pitch movement with right-hand rules.

    Science.gov (United States)

    Bahill, A Terry; Baldwin, David G

    2007-07-01

    The right-hand rules show the direction of the spin-induced deflection of baseball pitches: thus, they explain the movement of the fastball, curveball, slider and screwball. The direction of deflection is described by a pair of right-hand rules commonly used in science and engineering. Our new model for the magnitude of the lateral spin-induced deflection of the ball considers the orientation of the axis of rotation of the ball relative to the direction in which the ball is moving. This paper also describes how models based on somatic metaphors might provide variability in a pitcher's repertoire.

  8. Extracting attempted hand movements from EEGs in people with complete hand paralysis following stroke

    Directory of Open Access Journals (Sweden)

    Abirami eMuralidharan

    2011-03-01

    Full Text Available This study examines the feasibility of using electroencephalograms (EEGs to rapidly detect the intent to open one’s hand in individuals with complete hand paralysis following a subcortical ischemic stroke. If detectable, this motor planning activity could be used in real time to trigger a motorized hand exoskeleton or an electrical stimulation device that opens/closes the hand. While EEG-triggered movement-assist devices could restore function, they may also promote recovery by reinforcing the use of remaining cortical circuits. EEGs were recorded while participants were cued to either relax or attempt to extend their fingers. Linear discriminant analysis was used to detect onset of finger extension from the EEGs in a leave-one-trial-out cross-validation process. In each testing trial, the classifier was applied in pseudo real time starting from an initial hand-relaxed phase, through movement planning, and into the initial attempted finger extension phase (finger extension phase estimated from typical time-to-movement-onset measured in the unaffected hand. The classifiers detected attempted finger-extension at a significantly higher rate during both motor planning and early attempted execution compared to rest. To reduce inappropriate triggering of a movement-assist device during rest, the classification threshold could be adjusted to require more certainty about one’s intent to move before triggering a device. Additionally, a device could be set to activate only after multiple time samples in a row were classified as finger extension events. These options resulted in some sessions with no false triggers while the person was resting, but moderate-to-high true trigger rates during attempted movements.

  9. On the other hand: overflow movements of infants' hands and legs during unimanual object exploration.

    Science.gov (United States)

    Soska, Kasey C; Galeon, Margaret A; Adolph, Karen E

    2012-05-01

    Motor overflow is extraneous movement in a limb not involved in a motor action. Typically, overflow is observed in people with neurological impairments and in healthy children and adults during strenuous and attention-demanding tasks. In the current study, we found that young infants produce vast amounts of motor overflow, corroborating claims of symmetry being the default state of the motor system. While manipulating an object with one hand, all 27 of the typically developing 4.5- to 7.5-month-old infants who we observed displayed overflow movements of the free hand (on 4/5 of unimanual actions). Mirror-image movements of the hands occurred on 1/8 of unimanual actions, and the hands and legs moved in synchrony on 1/3 of unimanual acts. Motor overflow was less frequent when infants were in a sitting posture and when infants watched their acting hand, suggesting that upright posture and visual examination may help to alleviate overflow and break obligatory symmetry in healthy infants.

  10. Quantifying the quality of hand movement in stroke patients through three-dimensional curvature

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    Osu Rieko

    2011-10-01

    Full Text Available Abstract Background To more accurately evaluate rehabilitation outcomes in stroke patients, movement irregularities should be quantified. Previous work in stroke patients has revealed a reduction in the trajectory smoothness and segmentation of continuous movements. Clinically, the Stroke Impairment Assessment Set (SIAS evaluates the clumsiness of arm movements using an ordinal scale based on the examiner's observations. In this study, we focused on three-dimensional curvature of hand trajectory to quantify movement, and aimed to establish a novel measurement that is independent of movement duration. We compared the proposed measurement with the SIAS score and the jerk measure representing temporal smoothness. Methods Sixteen stroke patients with SIAS upper limb proximal motor function (Knee-Mouth test scores ranging from 2 (incomplete performance to 4 (mild clumsiness were recruited. Nine healthy participant with a SIAS score of 5 (normal also participated. Participants were asked to grasp a plastic glass and repetitively move it from the lap to the mouth and back at a conformable speed for 30 s, during which the hand movement was measured using OPTOTRAK. The position data was numerically differentiated and the three-dimensional curvature was computed. To compare against a previously proposed measure, the mean squared jerk normalized by its minimum value was computed. Age-matched healthy participants were instructed to move the glass at three different movement speeds. Results There was an inverse relationship between the curvature of the movement trajectory and the patient's SIAS score. The median of the -log of curvature (MedianLC correlated well with the SIAS score, upper extremity subsection of Fugl-Meyer Assessment, and the jerk measure in the paretic arm. When the healthy participants moved slowly, the increase in the jerk measure was comparable to the paretic movements with a SIAS score of 2 to 4, while the MedianLC was distinguishable

  11. Interaction between the premotor processes of eye and hand movements: possible mechanism underlying eye-hand coordination.

    Science.gov (United States)

    Hiraoka, Koichi; Kurata, Naoatsu; Sakaguchi, Masato; Nonaka, Kengo; Matsumoto, Naoto

    2014-03-01

    Interaction between the execution process of eye movement and that of hand movement must be indispensable for eye-hand coordination. The present study investigated corticospinal excitability in the hand muscles during the premotor processes of eye and/or hand movement to elucidate interaction between these processes. Healthy humans performed a precued reaction task of eye and/or finger movement and motor-evoked potentials in the hand muscles were evoked in the reaction time. Leftward eye movement suppressed corticospinal excitability in the right abductor digiti minimi muscle only when little finger abduction was simultaneously executed. Corticospinal excitability in the first dorsal interosseous muscle was not suppressed by eye movement regardless of whether or not it was accompanied by finger movement. Suppression of corticospinal excitability in the hand muscles induced by eye movement in the premotor period depends on the direction of eye movement, the muscle tested, and the premotor process of the tested muscle. The suppression may reflect interaction between the motor process of eye movement and that of hand movement particularly active during eye-hand coordination tasks during which both processes proceed.

  12. [Human traveling wave EEG during voluntary movement of the hand].

    Science.gov (United States)

    Belov, D R; Stepanova, P A; Kolodiazhnyĭ, S F

    2014-01-01

    The traveling wave trajectories connected with the movements of the right hand were revealed. Above sensomotor cortex 28 electrodes were set as a rectangle--4 rows with 7 electrodes in each one. 2D center-out reaching task was used. The target appeared on the screen edge through the random intervals 0.5-2.5 s equiprobably at the left, on the right, from above or from below. The task was to touch the target with the joystick-operated cursor displacing the cursor in one of the sides from the center to edge. EEG from the target occurrence till cursor contact with it was analyzed. Leading on phase of spontaneous EEG waves in the local area of the left sensomotor cortex and in the centre of back-parietal cortex during cursor movement downwards (the hand with joystick moves to oneself) comparing to rest state and movements in three other directions is revealed. The over time smoothing of data concerning phase alignment reveals hidden constant components in EEG resembling evoked potentials.

  13. Observing Repetitive Finger Movements Modulates Response Times of Auditorily Cued Finger Movements

    Science.gov (United States)

    Biermann-Ruben, Katja; Jonas, Melanie; Kessler, Klaus; Siebner, Hartwig Roman; Baumer, Tobias; Schnitzler, Alfons; Munchau, Alexander

    2008-01-01

    Our motor and perceptual representations of actions seem to be intimately linked and the human mirror neuron system (MNS) has been proposed as the mediator. In two experiments, we presented biological or non-biological movement stimuli that were either congruent or incongruent to a required response prompted by a tone. When the tone occurred with…

  14. Control strategy of hand movement depends on target redundancy.

    Science.gov (United States)

    Togo, Shunta; Yoshioka, Toshinori; Imamizu, Hiroshi

    2017-03-31

    Reaching toward a point target has been intensively studied in human motor control. However, little is known about reaching toward a redundant target, such as grasping a bar, in which the grasping point is irrelevant to the achievement of a task. We examined whether humans could solve the target-redundancy and control problems in a serial fashion or control their body without solving the target-redundancy problem. We equalized the target ranges between two reaching tasks: a point-to-point reaching task without target-redundancy and a point-to-bar reaching task with target-redundancy. In the both tasks, we measured hand viscoelasticity at movement end as parameters that reflect the adopted control strategy. As a result, the hand viscoelasticity in the point-to-bar reaching task was smaller than that in the point-to-point reaching task, even under the same kinematics. These results indicate that the hand viscoelasticity was modulated depending on the target-redundancy. Moreover, it is suggested that a human reaches toward a redundant target by effectively utilizing information of target redundancy rather than explicitly solving the target-redundancy problem.

  15. Changes in the relationship between movement velocity and movement distance in primary focal hand dystonia.

    Science.gov (United States)

    Prodoehl, Janey; Corcos, Daniel M; Leurgans, Sue; Comella, Cynthia L; Weis-McNulty, Annette; MacKinnon, Colum D

    2008-07-01

    The authors examined the relationship between movement velocity and distance and the associated muscle activation patterns in 18 individuals with focal hand dystonia (FHD) compared with a control group of 18 individuals with no known neuromuscular condition. Participants performed targeted voluntary wrist and elbow flexion movements as fast as possible across 5 movement distances. Individuals with FHD were slower than controls across all distances, and this difference was accentuated for longer movements. Muscle activation patterns were triphasic in the majority of individuals with FHD, and muscle activation scaled with distance in a similar manner to controls. Cocontraction did not explain movement slowing in individuals with dystonia, but there was a trend toward underactivation of the 1st agonist burst in the dystonic group. The authors concluded that slowness is a consistent feature of voluntary movement in FHD and is present even in the absence of dystonic posturing. Underactivation of the 1st agonist burst appears to be the most likely reason to explain slowing.

  16. Hand Movements and Braille Reading Efficiency: Data from the Alphabetic Braille and Contracted Braille Study

    Science.gov (United States)

    Wright, Tessa; Wormsley, Diane P.; Kamei-Hannan, Cheryl

    2009-01-01

    Using a subset of data from the Alphabetic Braille and Contracted Braille Study, researchers analyzed the patterns and characteristics of hand movements as predictors of reading performance. Statistically significant differences were found between one- and two-handed readers and between patterns of hand movements and reading rates. (Contains 6…

  17. Non-dominant hand movement facilitates the frontal N30 somatosensory evoked potential

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    Legon Wynn

    2010-09-01

    Full Text Available Abstract Background Previous literature has shown that the frontal N30 is increased during movement of the hand contralateral to median nerve stimulation. This finding was a result of non-dominant left hand movement in right-handed participants. It is unclear however if the effect depends upon non-dominant hand movement or if this is a generalized phenomenon across the upper-limbs. This study tests the effect of dominant and non-dominant hand movement upon contralateral frontal and parietal somatosensory evoked potentials (SEPs and further tests if this relationship persists in left hand dominant participants. Median nerve SEPs were elicited from the wrist contralateral to movement in both right hand and left hand dominant participants alternating the movement hand in separate blocks. Participants were required to volitionally squeeze (~ 20% of a maximal voluntary contraction a pressure-sensitive bulb every ~3 seconds with the hand contralateral to median nerve stimulation. SEPs were continuously collected during the task and individual traces were grouped into time bins relative to movement according to the timing of components of the Bereitschaftspotential. SEPs were then averaged and quantified from both FCZ and CP3/4 scalp electrode sites during both the squeeze task and at rest. Results The N30 is facilitated during non-dominant hand movement in both right and left hand dominant individuals. There was no effect for dominant hand movement in either group. Conclusions N30 amplitude increase may be a result of altered sensory gating from motor areas known to be specifically active during non-dominant hand movement.

  18. Adaptation of the Transverse Carpal Ligament Associated with Repetitive Hand Use in Pianists.

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    Christiane Mhanna

    Full Text Available The transverse carpal ligament (TCL plays a critical role in carpal tunnel biomechanics through interactions with its surrounding tissues. The purpose of this study was to investigate the in vivo adaptations of the TCL's mechanical properties in response to repetitive hand use in pianists using acoustic radiation force impulse (ARFI imaging. It was hypothesized that pianists, in comparison to non-pianists, would have a stiffer TCL as indicated by an increased acoustic shear wave velocity (SWV. ARFI imagining was performed for 10 female pianists and 10 female non-pianists. The median SWV values of the TCL were determined for the entire TCL, as well as for its radial and ulnar portions, rTCL and uTCL, respectively. The TCL SWV was significantly increased in pianists relative to non-pianists (p < 0.05. Additionally, the increased SWV was location dependent for both pianist and non-pianist groups (p < 0.05, with the rTCL having a significantly greater SWV than the uTCL. Between groups, the rTCL SWV of pianists was 22.2% greater than that of the non-pianists (p < 0.001. This localized increase of TCL SWV, i.e. stiffening, may be primarily attributable to focal biomechanical interactions that occur at the radial TCL aspect where the thenar muscles are anchored. Progressive stiffening of the TCL may become constraining to the carpal tunnel, leading to median nerve compression in the tunnel. TCL maladaptation helps explain why populations who repeatedly use their hands are at an increased risk of developing musculoskeletal pathologies, e.g. carpal tunnel syndrome.

  19. OCRA: a concise index for the assessment of exposure to repetitive movements of the upper limbs.

    Science.gov (United States)

    Occhipinti, E

    1998-09-01

    In the light of data and speculation contained in the literature, and based on procedures illustrated in a previous research project in which the author described and evaluated occupational risk factors associated with work-related musculoskeletal disorders of the upper limbs (WMSDs), this paper proposes a method for calculating a concise index of exposure to repetitive movements of the upper limbs. The proposal, which still has to be substantiated and validated by further studies and applications, is conceptually based on the procedure recommended by the NIOSH for calculating the Lifting Index in manual load handling activities. The concise exposure index (OCRA index) in this case is based on the relationship between the daily number of actions actually performed by the upper limbs in repetitive tasks, and the corresponding number of recommended actions. The latter are calculated on the basis of a constant (30 actions per minute), which represents the action frequency factor; it is valid--hypothetically--under so-called optimal conditions; the constant is diminished case by case (using appropriate factors) as a function of the presence and characteristics of the other risk factors (force, posture, additional elements, recovery periods). Although still experimental, the exposure index can be used to obtain an integrated and concise assessment of the various risk factors analysed and to classify occupational scenarios featuring significant and diversified exposure to such risk factors.

  20. Modeling movements of a long hand-held tool with effects of moments of inertia.

    Science.gov (United States)

    Lin, Chiuhsiang Joe; Chen, Hung-Jen

    2014-04-01

    The current experiment aimed to investigate the effects of weight position on movement time in target acquisition tasks. Subsequently, a simple mathematical model was developed to describe the movement time with the moments of inertia. Ten right-handed participants conducted continuous Fitts pointing tasks using a laparoscopic instrument as a long hand-held tool. The results showed significant effects of weight position on movement time. Furthermore, an extended Fitts' law model is proposed for the moments of inertia produced by the hand, instrument, and a constant mass in different positions. This predictive model accounted for 63% of the variance in movement time. The predictive model proposed in the present study can be applied not only to estimate movement time given a particular target width, instrument movement amplitude, and weight position of a long hand-held tool but also to standardize movement time and establish training standards.

  1. Kinematic parameters of hand movement during a disparate bimanual movement task in children with unilateral Cerebral Palsy.

    Science.gov (United States)

    Rudisch, Julian; Butler, Jenny; Izadi, Hooshang; Zielinski, Ingar Marie; Aarts, Pauline; Birtles, Deirdre; Green, Dido

    2016-04-01

    Children with unilateral Cerebral Palsy (uCP) experience problems performing tasks requiring the coordinated use of both hands (bimanual coordination; BC). Additionally, some children with uCP display involuntary symmetrical activation of the opposing hand (mirrored movements). Measures, used to investigate therapy-related improvements focus on the functionality of the affected hand during unimanual or bimanual tasks. None however specifically address spatiotemporal integration of both hands. We explored the kinematics of hand movements during a bimanual task to identify parameters of BC. Thirty-seven children (aged 10.9±2.6years, 20 male) diagnosed with uCP participated. 3D kinematic motion analysis was performed during the task requiring opening of a box with their affected- (AH) or less-affected hand (LAH), and pressing a button inside with the opposite hand. Temporal and spatial components of data were extracted and related to measures of hand function and level of impairment. Total task duration was correlated with the Jebsen-Taylor Test of Hand Function in both conditions (either hand leading with the lid-opening). Spatial accuracy of the LAH when the box was opened with their AH was correlated with outcomes on the Children's Hand Use Experience Questionnaire. Additionally, we found a subgroup of children displaying non-symmetrical movement interference associated with greater movement overlap when their affected hand opened the box. This subgroup also demonstrated decreased use of the affected hand during bimanual tasks. Further investigation of bimanual interference, which goes beyond small scaled symmetrical mirrored movements, is needed to consider its impact on bimanual task performance following early unilateral brain injury. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. [Coordination patterns assessed by a continuous measure of joints coupling during upper limb repetitive movements].

    Science.gov (United States)

    Draicchio, F; Silvetti, A; Ranavolo, A; Iavicoli, S

    2008-01-01

    We analyzed the coordination patterns between elbow, shoulder and trunk in a motor task consisting of reaching out, picking up a cylinder, and transporting it back by using the Dynamical Systems Theory and calculating the continuous relative phase (CRP), a continuous measure of the coupling between two interacting joints. We used an optoelectronic motion analysis system consisting of eight infra-red ray cameras to detect the movements of nine skin-mounted markers. We calculated the root square of the adjusted coefficient of determination, the coefficient of multiple correlation (CMC), in order to investigate the repeatability of the joints coordination. The data confirm that the CNS establishes both synergic (i.e. coupling between shoulder and trunk on the frontal plane) and hierarchical (i.e. coupling between elbow-shoulder-trunk on the horizontal plane) relationships among the available degrees of freedom to overcome the complexity due to motor redundancy. The present study describes a method to investigate the organization of the kinematic degrees of freedom during upper limb multi-joint motor tasks that can be useful to assess upper limb repetitive movements.

  3. Observation of Hand Movements by Older Persons with Dementia : Effects on Cognition

    NARCIS (Netherlands)

    Eggermont, Laura H. P.; Swaab, Dick F.; Hol, Elly M.; Scherder, Erik J. A.

    2009-01-01

    Background/Aim: Hand movement observation activates mirror neurons, located in brain areas that are vulnerable to Alzheimer's disease. We examined the effects of hand movement observation on cognition in older persons with dementia. Methods: Nursing home residents with dementia (n = 44) watched eith

  4. Classifying sEMG-based Hand Movements by Means of Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    M. S. Isaković

    2015-06-01

    Full Text Available In order to improve surface electromyography (sEMG based control of hand prosthesis, we applied Principal Component Analysis (PCA for feature extraction. The sEMG data from a group of healthy subjects (downloaded from free Ninapro database comprised the following sets: three grasping, eight wrist, and eleven finger movements. We tested the accuracy of a simple quadratic classifier for two sets of features derived from PCA. Preliminary results suggest that the first two principal components do not guarantee successful hand movement classification. The hand movement classification accuracy significantly increased with using three instead of two features, in all three sets of movements and throughout all subjects.

  5. Uncertainty in aiming movements and its association to hand function

    Directory of Open Access Journals (Sweden)

    Flávia Priscila de Paiva Silva

    2015-09-01

    Full Text Available AbstractThe purpose of this study was to analyze the influence of the uncertainty of target location on the planning and execution of aiming movements performed towards the ipsilateral and contralateral directions by the right and left upper limbs. In addition, the association between the performance of aiming movements and the performance of functional manual tasks was investigated. Two tasks were proposed: with prior knowledge of the movement direction (simple reaction time or not (choice reaction time. The grip strength and manual dexterity were measured. The choice option in response (i.e. uncertainty influenced planning of the aiming movements, but not its execution, while movements performed towards the contralateral direction were worse in execution as compared to the ipsilateral direction. Manual dexterity was significantly correlated with reaction times, while the performance during movement execution was significantly correlated with handgrip/pinch strength.

  6. The impact of text repetition on content and function words during reading: further evidence from eye movements.

    Science.gov (United States)

    Chamberland, Cindy; Saint-Aubin, Jean; Légère, Marie-Andrée

    2013-06-01

    There is ample evidence that reading speed increases when participants read the same text more than once. However, less is known about the impact of text repetition as a function of word class. Some authors suggested that text repetition would mostly benefit content words with little or no effect on function words. In the present study, we examined the effect of multiple readings on the processing of content and function words. Participants were asked to read a short text two times in direct succession. Eye movement analyses revealed the typical multiple readings effect: Repetition decreased the time readers spent fixating words and the probability of fixating critical words. Most importantly, we found that the effect of multiple readings was of the same magnitude for content and function words, and for low- and high-frequency words. Such findings suggest that lexical variables have additive effects on eye movement measures in reading.

  7. Kinematic parameters of hand movement during a disparate bimanual movement task in children with unilateral Cerebral Palsy

    NARCIS (Netherlands)

    Rudisch, J.; Butler, J.; Izadi, H.; Zielinski, I.M.; Aarts, P.B.M.; Birtles, D.; Green, D.

    2016-01-01

    Children with unilateral Cerebral Palsy (uCP) experience problems performing tasks requiring the coordinated use of both hands (bimanual coordination; BC). Additionally, some children with uCP display involuntary symmetrical activation of the opposing hand (mirrored movements). Measures, used to inv

  8. Repeatability of the timing of eye-hand coordinated movements across different cognitive tasks.

    Science.gov (United States)

    de Boer, C; van der Steen, J; Schol, R J; Pel, J J M

    2013-08-15

    Quantification of eye-hand coordinated behaviour is a relatively new tool to study neurodegeneration in humans. Its sensitivity depends on the assessment of different behavioural strategies, multiple task testing and repeating tasks within one session. However, large numbers of repetition trials pose a significant burden on subjects. To introduce this method in large-scale population studies, it is necessary to determine whether reducing the number of task repetitions, which will lower subject burden, still leads to acceptable measurement accuracy. The objective of this study was to investigate the validity and reliability of eye-hand coordination outcome parameters in eight healthy volunteers using a test-retest approach. Subjects were assessed during a shortened test procedure consisting of eight repetitions of three behavioural tasks: a reflex-based tapping task, a planning-based tapping task and a memory-based tapping task. Eye-hand coordination was quantified in terms of timing (eye and hand latencies), kinematics and accuracy. Eye and hand latencies were found within a normal range (between 150 and 450ms). A paired samples t-test revealed no differences in timing parameters between the first and second measurements. It was concluded that eight trial repetitions are sufficient for quantifying eye-hand coordination in terms of timing, kinematics and accuracy. This approach demonstrates the testing of multiple visuomotor behaviours within a reasonable time span of a few minutes per task.

  9. Human cortical control of hand movements: parietofrontal networks for reaching, grasping, and pointing.

    Science.gov (United States)

    Filimon, Flavia

    2010-08-01

    In primates, control of the limb depends on many cortical areas. Whereas specialized parietofrontal circuits have been proposed for different movements in macaques, functional neuroimaging in humans has revealed widespread, overlapping activations for hand and eye movements and for movements such as reaching and grasping. This review examines the involvement of frontal and parietal areas in hand and arm movements in humans as revealed with functional neuroimaging. The degree of functional specialization, possible homologies with macaque cortical regions, and differences between frontal and posterior parietal areas are discussed, as well as a possible organization of hand movements with respect to different spatial reference frames. The available evidence supports a cortical organization along gradients of sensory (visual to somatosensory) and effector (eye to hand) preferences.

  10. Fuzzy Deductive Inference Scheme Application in Solving the Problem of Modelling Movements of the Hand Prosthesis

    Directory of Open Access Journals (Sweden)

    Bozhenyuk Alexander

    2015-12-01

    Full Text Available The decision-making model with basic fuzzy rule modus ponens is suggested in this paper to control the hand prosthesis. The hand movements are described by angles of finger and wrist flexion. Electromyogram (EMG of hand muscles was used as a source of the input data. Software was developed to implement the decision-making model with fuzzy rule modus ponens. In particular, the software receives EMG data, executes calculations and visualises the output data. The key advantage of the model is smoothness of output data changes; this way a maximum approach to natural hand movements is reached.

  11. Learning effects of repetitive administration of the Southampton Hand Assessment Procedure in novice prosthetic users

    NARCIS (Netherlands)

    Golea-Vasluian, Ecaterina; Bongers, Raoul M; Reinders-Messelink, Heleen A; Burgerhof, Johannes G M; Dijkstra, Pieter U.; van der Sluis, Corry K

    2014-01-01

    Objective: The Southampton Hand Assessment Procedure (SHAP) evaluates the functionality of normal, injured or prosthetic hands. The aim was to evaluate the learning effects of SHAP tasks and the appropriateness of the time limits applied per task in novice prosthetic users. Methods: Right-handed uni

  12. The risk of musculoskeletal disorders due to repetitive movements of upper limbs for workers employed in hazelnut sorting

    Directory of Open Access Journals (Sweden)

    Andrea Colantoni

    2013-09-01

    Full Text Available In the agro-industrial sector there are many activities whose urgent rhythms can cause a considerable exposure to bio-mechanical risk factors. In the hazelnut sorting, the workers are subject to several biomechanical risks, with repetitive movements, and operations that require a remarkable degree of strength. A thorough study of the workers’ exposure to repetitive manual movements has been carried out, with the aim of setting up the necessary measures to reduce the risk factors. The aim of the research is to assess the risk of work-related musculo-skeletal disorders (WMSDs due to repetitive work, for workers employed to hazelnut shells sorting. The research was carried out in an agricultural cooperative in the Viterbo’s area. For risk assessment authors used a method (Occupational Repetitive Actions “OCRA” index according to ISO 11228- 3:2009, Ergonomics - Manual handling - Part 3: Handling of low loads at high frequency which keeps into consideration several risk factors (such as repetitiveness, prehension force, posture. The risk was assessed for 16 female workers (in eight workplaces and in two different shifts through this classification: workers with experience less than 1 year, from 1 to 10 years and more than 10 years. This classification is very important for knowing if the professional experience could be considered a “prevention measure” for the risk reduction. The results show a high risk level for the right and left limb. The factors which more have contributed to reach such risk level are the great number of movements and the lack of recovering time.

  13. Use of the Argus II retinal prosthesis to improve visual guidance of fine hand movements

    OpenAIRE

    2012-01-01

    We studied the capabilities of the Argus II retinal prosthesis for guiding fine hand movement, and demonstrated and quantified guidance improvement when using the device over when not using the device for progressively less predictable trajectories.

  14. Continuous involuntary hand movements and schizencephaly: epilepsia partialis continua or dystonia?

    Science.gov (United States)

    Marinelli, Lucio; Bonzano, Laura; Saitta, Laura; Trompetto, Carlo; Abbruzzese, Giovanni

    2012-04-01

    Schizencephaly is regarded as a malformation of cortical development (due to abnormal neuronal organization) and may be associated with continuous involuntary hand movements. The mechanisms underlying these movements are not clear and both dystonia and epilepsia partialis continua have been considered in previously reported cases. We describe a young patient affected by schizencephaly and continuous involuntary movements of the contralateral hand. Functional MRI showed bilateral cerebral activation, while the subject performed tapping movements with the affected hand and no significant difference in the activation pattern after diazepam infusion. Standard and back-averaged EEG showed no alterations. The results obtained from these investigations and the clinical features of the involuntary movements are not in favor of an epileptic genesis, while support the diagnosis of secondary dystonia.

  15. Effects of Repetitive Transcranial Magnetic Stimulation in Performing Eye-Hand Integration Tasks: Four Preliminary Studies with Children Showing Low-Functioning Autism

    Science.gov (United States)

    Panerai, Simonetta; Tasca, Domenica; Lanuzza, Bartolo; Trubia, Grazia; Ferri, Raffaele; Musso, Sabrina; Alagona, Giovanna; Di Guardo, Giuseppe; Barone, Concetta; Gaglione, Maria P.; Elia, Maurizio

    2014-01-01

    This report, based on four studies with children with low-functioning autism, aimed at evaluating the effects of repetitive transcranial magnetic stimulation delivered on the left and right premotor cortices on eye-hand integration tasks; defining the long-lasting effects of high-frequency repetitive transcranial magnetic stimulation; and…

  16. Activation differences in observation of hand movements for imitation or velocity judgement.

    Science.gov (United States)

    Suchan, Boris; Melde, Cornelia; Herzog, Hans; Hömberg, Volker; Seitz, Rüdiger J

    2008-03-17

    We aimed to investigate the brain areas engaged in observation of hand movements with the intention of imitation or judging movement velocity. Both processes reflect different analytic approaches in movement observation. We were interested if these two processes can be distinguished or share common activation foci. Twelve healthy, right-handed volunteers were required to observe video clips of hand gestures and of object related grasping movements while the regional cerebral blood flow was measured using positron emission tomography. The subjects were instructed either to imitate the actions or to judge the velocity of the observed movements after scanning. Action observation with the instruction to judge movement velocity engaged bilaterally the temporo-occipital junction and adjacent visual cortical areas. In contrast, observation with the instruction to imitate them afterwards, yielded large activation clusters covering the left parietal and premotor cortex. Both contrasts demonstrated activation in the inferior frontal cortex, however, on opposite sides. Results suggest that movement observation with the goal of imitation activated specific areas of the parietal cortex in the dominant hemisphere probably related to programming of the movement kinematics. In contrast, observation with the goal to characterize the velocity of the finger movements activated the ventral visual pathways. Thus, movement observation recruits non-overlapping cortical networks, depending on the information attended to which are characterised by a dorsal ventral dissociation.

  17. Contributions of skin and muscle afferent input to movement sense in the human hand.

    Science.gov (United States)

    Cordo, Paul J; Horn, Jean-Louis; Künster, Daniela; Cherry, Anne; Bratt, Alex; Gurfinkel, Victor

    2011-04-01

    In the stationary hand, static joint-position sense originates from multimodal somatosensory input (e.g., joint, skin, and muscle). In the moving hand, however, it is uncertain how movement sense arises from these different submodalities of proprioceptors. In contrast to static-position sense, movement sense includes multiple parameters such as motion detection, direction, joint angle, and velocity. Because movement sense is both multimodal and multiparametric, it is not known how different movement parameters are represented by different afferent submodalities. In theory, each submodality could redundantly represent all movement parameters, or, alternatively, different afferent submodalities could be tuned to distinctly different movement parameters. The study described in this paper investigated how skin input and muscle input each contributes to movement sense of the hand, in particular, to the movement parameters dynamic position and velocity. Healthy adult subjects were instructed to indicate with the left hand when they sensed the unseen fingers of the right hand being passively flexed at the metacarpophalangeal (MCP) joint through a previously learned target angle. The experimental approach was to suppress input from skin and/or muscle: skin input by anesthetizing the hand, and muscle input by unexpectedly extending the wrist to prevent MCP flexion from stretching the finger extensor muscle. Input from joint afferents was assumed not to play a significant role because the task was carried out with the MCP joints near their neutral positions. We found that, during passive finger movement near the neutral position in healthy adult humans, both skin and muscle receptors contribute to movement sense but qualitatively differently. Whereas skin input contributes to both dynamic position and velocity sense, muscle input may contribute only to velocity sense.

  18. Corticospinal Excitability in the Hand Muscles is Decreased During Eye Movement with Visual Occlusion.

    Science.gov (United States)

    Chujo, Yuta; Jono, Yasutomo; Tani, Keisuke; Nomura, Yoshifumi; Hiraoka, Koichi

    2016-02-01

    Corticospinal excitability in the hand muscles decreases during smooth pursuit eye movement. The present study tested a hypothesis that the decrease in corticospinal excitability in the hand muscles at rest during eye movement is not caused by visual feedback but caused by motor commands to the eye muscles. Healthy men (M age = 28.4 yr., SD = 5.2) moved their eyes to the right with visual occlusion (dark goggles) while their arms and hands remained at rest. The motor-evoked potential in the hand muscles was suppressed by 19% in the third quarter of the eye-movement period, supporting a view that motor commands to the eye muscles are the cause of the decrease in corticospinal excitability in the hand muscles. The amount of the suppression was not significantly different among the muscles, indicating that modulation of corticospinal excitability in one muscle induced by eye movement is not dependent on whether eye movement direction and the direction of finger movement when the muscle contracts are identical. Thus, the finding failed to support a hypothetical view that motor commands to the eye muscles concomittantly produce motor commands to the hand muscles. Moreover, the amount of the suppression was not significantly different between the forearm positions, indicating that the suppression was not affected by proprioception of the forearm muscles when visual feedback is absent. © The Author(s) 2016.

  19. Movement paths in operating hand-held tools: tests of distal-shift hypotheses.

    Science.gov (United States)

    Sülzenbrück, Sandra; Heuer, Herbert

    2013-06-01

    Extending the body with a tool could imply that characteristics of hand movements become characteristics of the movement of the effective part of the tool. Recent research suggests that such distal shifts are subject to boundary conditions. Here we propose the existence of three constraints: a strategy constraint, a constraint of movement characteristics, and a constraint of mode of control. We investigate their validity for the curvature of transverse movements aimed at a target while using a sliding first-order lever. Participants moved the tip of the effort arm of a real or virtual lever to control a cursor representing movements of the tip of the load arm of the lever on a monitor. With this tool, straight transverse hand movements are associated with concave curvature of the path of the tip of the tool. With terminal visual feedback and when targets were presented for the hand, hand paths were slightly concave in the absence of the dynamic transformation of the tool and slightly convex in its presence. When targets were presented for the tip of the lever, both the concave and convex curvatures of the hand paths became stronger. Finally, with continuous visual feedback of the tip of the lever, curvature of hand paths became convex and concave curvature of the paths of the tip of the lever was reduced. In addition, the effect of the dynamic transformation on curvature was attenuated. These findings support the notion that distal shifts are subject to at least the three proposed constraints.

  20. Linear and nonlinear subspace analysis of hand movements during grasping.

    Science.gov (United States)

    Cui, Phil Hengjun; Visell, Yon

    2014-01-01

    This study investigated nonlinear patterns of coordination, or synergies, underlying whole-hand grasping kinematics. Prior research has shed considerable light on roles played by such coordinated degrees-of-freedom (DOF), illuminating how motor control is facilitated by structural and functional specializations in the brain, peripheral nervous system, and musculoskeletal system. However, existing analyses suppose that the patterns of coordination can be captured by means of linear analyses, as linear combinations of nominally independent DOF. In contrast, hand kinematics is itself highly nonlinear in nature. To address this discrepancy, we sought to to determine whether nonlinear synergies might serve to more accurately and efficiently explain human grasping kinematics than is possible with linear analyses. We analyzed motion capture data acquired from the hands of individuals as they grasped an array of common objects, using four of the most widely used linear and nonlinear dimensionality reduction algorithms. We compared the results using a recently developed algorithm-agnostic quality measure, which enabled us to assess the quality of the dimensional reductions that resulted by assessing the extent to which local neighborhood information in the data was preserved. Although qualitative inspection of this data suggested that nonlinear correlations between kinematic variables were present, we found that linear modeling, in the form of Principle Components Analysis, could perform better than any of the nonlinear techniques we applied.

  1. The Moving Rubber Hand Illusion Reveals that Explicit Sense of Agency for Tapping Movements Is Preserved in Functional Movement Disorders.

    Science.gov (United States)

    Marotta, Angela; Bombieri, Federica; Zampini, Massimiliano; Schena, Federico; Dallocchio, Carlo; Fiorio, Mirta; Tinazzi, Michele

    2017-01-01

    Functional movement disorders (FMD) are characterized by motor symptoms (e.g., tremor, gait disorder, and dystonia) that are not compatible with movement abnormalities related to a known organic cause. One key clinical feature of FMD is that motor symptoms are similar to voluntary movements but are subjectively experienced as involuntary by patients. This gap might be related to abnormal self-recognition of bodily action, which involves two main components: sense of agency and sense of body ownership. The aim of this study was to systematically investigate whether this function is altered in FMD, specifically focusing on the subjective feeling of agency, body ownership, and their interaction during normal voluntary movements. Patients with FMD (n = 21) and healthy controls (n = 21) underwent the moving Rubber Hand Illusion (mRHI), in which passive and active movements can differentially elicit agency, ownership or both. Explicit measures of agency and ownership were obtained via a questionnaire. Patients and controls showed a similar pattern of response: when the rubber hand was in a plausible posture, active movements elicited strong agency and ownership; implausible posture of the rubber hand abolished ownership but not agency; passive movements suppressed agency but not ownership. These findings suggest that explicit sense of agency and body ownership are preserved in FMD. The latter finding is shared by a previous study in FMD using a static version of the RHI, whereas the former appears to contrast with studies demonstrating altered implicit measures of agency (e.g., sensory attenuation). Our study extends previous findings by suggesting that in FMD: (i) the sense of body ownership is retained also when interacting with the motor system; (ii) the subjective experience of agency for voluntary tapping movements, as measured by means of mRHI, is preserved.

  2. The Moving Rubber Hand Illusion Reveals that Explicit Sense of Agency for Tapping Movements Is Preserved in Functional Movement Disorders

    Directory of Open Access Journals (Sweden)

    Angela Marotta

    2017-06-01

    Full Text Available Functional movement disorders (FMD are characterized by motor symptoms (e.g., tremor, gait disorder, and dystonia that are not compatible with movement abnormalities related to a known organic cause. One key clinical feature of FMD is that motor symptoms are similar to voluntary movements but are subjectively experienced as involuntary by patients. This gap might be related to abnormal self-recognition of bodily action, which involves two main components: sense of agency and sense of body ownership. The aim of this study was to systematically investigate whether this function is altered in FMD, specifically focusing on the subjective feeling of agency, body ownership, and their interaction during normal voluntary movements. Patients with FMD (n = 21 and healthy controls (n = 21 underwent the moving Rubber Hand Illusion (mRHI, in which passive and active movements can differentially elicit agency, ownership or both. Explicit measures of agency and ownership were obtained via a questionnaire. Patients and controls showed a similar pattern of response: when the rubber hand was in a plausible posture, active movements elicited strong agency and ownership; implausible posture of the rubber hand abolished ownership but not agency; passive movements suppressed agency but not ownership. These findings suggest that explicit sense of agency and body ownership are preserved in FMD. The latter finding is shared by a previous study in FMD using a static version of the RHI, whereas the former appears to contrast with studies demonstrating altered implicit measures of agency (e.g., sensory attenuation. Our study extends previous findings by suggesting that in FMD: (i the sense of body ownership is retained also when interacting with the motor system; (ii the subjective experience of agency for voluntary tapping movements, as measured by means of mRHI, is preserved.

  3. MusicGlove: motivating and quantifying hand movement rehabilitation by using functional grips to play music.

    Science.gov (United States)

    Friedman, Nizan; Chan, Vicky; Zondervan, Danny; Bachman, Mark; Reinkensmeyer, David J

    2011-01-01

    People with stroke typically must perform much of their hand exercise at home without professional assistance as soon as two weeks after the stroke. Without feedback and encouragement, individuals often lose motivation to practice using the affected hand, and this disuse contributes to further declines in hand function. We developed the MusicGlove as a way to facilitate and motivate at home practice of hand movement. This low-cost device uses music as an interactive and motivating medium to guide hand exercise and to quantitatively assess hand movement recovery. It requires the user to practice functional movements, including pincer grip, key-pinch grip, and finger-thumb opposition, by using those movements to play different musical notes, played along to songs displayed by an interactive computer game. We report here the design of the glove and the results of a single-session experiment with 10 participants with chronic stroke. We found that the glove is well suited for use by people with an impairment level quantified by a Box and Blocks score of at least around 7; that the glove can be used to obtain a measure of hand dexterity (% of notes hit) that correlates strongly with the Box and Blocks score; and that the incorporation of music into training significantly improved both objective measures of hand motor performance and self-ratings of motivation for training in the single session.

  4. On the Influence of Hand Dynamics on Motion Planning of Reaching Movements in Haptic Environments

    OpenAIRE

    Goncharenko, Igor; Svinin, Mikhail; Hosoe, Shigeyuki; Forstmann, Sven

    2010-01-01

    An analysis of human reaching movements in the task of mass transport is presented. Two models, the minimum hand jerk (MJC) and the minimum driving hand force-change (MFCC), are used for modelling and verification of experimental data. The data were collected with a haptic system supporting object dynamics simulation in real time. The

  5. Development of manipulative hand movements during the second year of life

    NARCIS (Netherlands)

    Geerts, WK; Einspieler, C; Dibiasi, J; Garzarolli, B; Bos, AF

    2003-01-01

    Background: Developmental testing in children is concerned mainly with a pass or fail on tasks such as grasping, manipulating and inserting. Knowledge about the qualitative development of hand movements in young children is scarce. Aim: We studied the qualitative development of manipulative hand mov

  6. Human motor development and hand laterality: a kinematic analysis of drawing movements.

    Science.gov (United States)

    Blank, R; Miller, V; von Voss, H

    2000-12-08

    This study examines the developmental profiles of basic 'open-loop' drawing movements on the non-dominant hand (ND) in comparison with the dominant hand (D). Fifty-three right-handed children aged 7-14 years and 15 adults aged 27-43 years were examined. Each subject drew lines and circles of different sizes at maximum velocity with a pressure-sensitive pen on a computer graphics tablet. Small lines were drawn at 90 degrees to the axis of the forearm (lines using wrist movements (LWM)) and along the axis of the forearm (lines using elbow movements (LEM)). Larger lines were drawn at 90 degrees to the axis of the forearm (LEM). At both extremities, the movement frequencies of the proximally generated drawing movements increased in a parallel fashion at different levels. In LWM, the right-left-differences (RLD) were high in 7- to 8-year-old children; until puberty, the ND hand reached almost the performance of the D hand. In contrast, the RLD of the LFM increased at the same time. As adulthood approaches, frequencies of all drawings increased further while the LWM on the ND side remained stable. In adults, there were similar RLD for all line drawings involving predominantly flexion and extension movements. When drawing circles, the RLD were highest, though stable in all age groups. Hand laterality of pen use changes over time; these changes are dependent on complexity (combined/sequential cf. flexion-extension muscle activation) and on topography (proximal cf. distal movements). Distinct developmental profiles of motoneuronal populations of the cortex may be responsible for the distinct hand laterality effects and the decreasing variability of motor patterns. The drawing abilities and developmental changes on the untrained ND hand indicate that effector-specific practice plays a minor role.

  7. Hand movements with a phase structure and gestures that depict action stem from a left hemispheric system of conceptualization.

    Science.gov (United States)

    Helmich, I; Lausberg, H

    2014-10-01

    The present study addresses the previously discussed controversy on the contribution of the right and left cerebral hemispheres to the production and conceptualization of spontaneous hand movements and gestures. Although it has been shown that each hemisphere contains the ability to produce hand movements, results of left hemispherically lateralized motor functions challenge the view of a contralateral hand movement production system. To examine hemispheric specialization in hand movement and gesture production, ten right-handed participants were tachistoscopically presented pictures of everyday life actions. The participants were asked to demonstrate with their hands, but without speaking what they had seen on the drawing. Two independent blind raters evaluated the videotaped hand movements and gestures employing the Neuropsychological Gesture Coding System. The results showed that the overall frequency of right- and left-hand movements is equal independent of stimulus lateralization. When hand movements were analyzed considering their Structure, the presentation of the action stimuli to the left hemisphere resulted in more hand movements with a phase structure than the presentation to the right hemisphere. Furthermore, the presentation to the left hemisphere resulted in more right and left-hand movements with a phase structure, whereas the presentation to the right hemisphere only increased contralateral left-hand movements with a phase structure as compared to hand movements without a phase structure. Gestures that depict action were primarily displayed in response to stimuli presented in the right visual field than in the left one. The present study shows that both hemispheres possess the faculty to produce hand movements in response to action stimuli. However, the left hemisphere dominates the production of hand movements with a phase structure and gestures that depict action. We therefore conclude that hand movements with a phase structure and gestures that

  8. Priming Hand Motor Training with Repetitive Stimulation of the Fingertips; Performance Gain and Functional Imaging of Training Effects.

    Science.gov (United States)

    Lotze, Martin; Ladda, Aija Marie; Roschka, Sybille; Platz, Thomas; Dinse, Hubert R

    Application of repetitive electrical stimulation (rES) of the fingers has been shown to improve tactile perception and sensorimotor performance in healthy individuals. To increase motor performance by priming the effects of active motor training (arm ability training; AAT) using rES. We compared the performance gain for the training increase of the averaged AAT tasks of both hands in two groups of strongly right-handed healthy volunteers. Functional Magnetic Resonance Imaging (fMRI) before and after AAT was assessed using three tasks for each hand separately: finger sequence tapping, visually guided grip force modulation, and writing. Performance during fMRI was controlled for preciseness and frequency. A total of 30 participants underwent a two-week unilateral left hand AAT, 15 participants with 20 minutes of rES priming of all fingertips of the trained hand, and 15 participants without rES priming. rES-primed AAT improved the trained left-hand performance across all training tasks on average by 32.9%, non-primed AAT improved by 29.5%. This gain in AAT performance with rES priming was predominantly driven by an increased finger tapping velocity. Functional imaging showed comparable changes for both training groups over time. Across all participants, improved AAT performance was associated with a higher contralateral primary somatosensory cortex (S1) fMRI activation magnitude during the grip force modulation task. This study highlights the importance of S1 for hand motor training gain. In addition, it suggests the usage of rES of the fingertips for priming active hand motor training. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. The dynamics of sensorimotor cortical oscillations during the observation of hand movements: an EEG study.

    Directory of Open Access Journals (Sweden)

    Pietro Avanzini

    Full Text Available BACKGROUND: The observation of action done by others determines a desynchronization of the rhythms recorded from cortical central regions. Here, we examined whether the observation of different types of hand movements (target directed, non-target directed, cyclic and non-cyclic elicits different EEG cortical temporal patterns. METHODOLOGY: Video-clips of four types of hand movements were shown to right-handed healthy participants. Two were target directed (grasping and pointing motor acts; two were non-target directed (supinating and clenching movements. Grasping and supinating were performed once, while pointing and clenching twice (cyclic movements. High-density EEG was recorded and analyzed by means of wavelet transform, subdividing the time course in time bins of 200 ms. The observation of all presented movements produced a desynchronization of alpha and beta rhythms in central and parietal regions. The rhythms desynchronized as soon as the hand movement started, the nadir being reached around 700 ms after movement onset. At the end of the movement, a large power rebound occurred for all bands. Target and non-target directed movements produced an alpha band desynchronization in the central electrodes at the same time, but with a stronger desynchronization and a prolonged rebound for target directed motor acts. Most interestingly, there was a clear correlation between the velocity profile of the observed movements and beta band modulation. SIGNIFICANCE: Our data show that the observation of motor acts determines a modulation of cortical rhythm analogous to that occurring during motor act execution. In particular, the cortical motor system closely follows the velocity of the observed movements. This finding provides strong evidence for the presence in humans of a mechanism (mirror mechanism mapping action observation on action execution motor programs.

  10. Early detection of hand movements from electroencephalograms for stroke therapy applications

    Science.gov (United States)

    Muralidharan, A.; Chae, J.; Taylor, D. M.

    2011-08-01

    Movement-assist devices such as neuromuscular stimulation systems can be used to generate movements in people with chronic hand paralysis due to stroke. If detectable, motor planning activity in the cortex could be used in real time to trigger a movement-assist device and restore a person's ability to perform many of the activities of daily living. Additionally, re-coupling motor planning in the cortex with assisted movement generation in the periphery may provide an even greater benefit—strengthening relevant synaptic connections over time to promote natural motor recovery. This study examined the potential for using electroencephalograms (EEGs) as a means of rapidly detecting the intent to open the hand during movement planning in individuals with moderate chronic hand paralysis following a subcortical ischemic stroke. On average, attempts to open the hand could be detected from EEGs approximately 100-500 ms prior to the first signs of movement onset. This earlier detection would minimize device activation delays and allow for tighter coupling between initial formation of the motor plan in the cortex and augmentation of that plan in the periphery by a movement-assist device. This tight temporal coupling may be important or even essential for strengthening synaptic connections and enhancing natural motor recovery.

  11. Epidural electrocorticography of phantom hand movement following long-term upper-limb amputation

    Directory of Open Access Journals (Sweden)

    Alireza eGharabaghi

    2014-05-01

    Full Text Available Introduction: Prostheses for upper-limb amputees are currently controlled by either myoelectric or peripheral neural signals. Performance and dexterity of these devices is still limited, particularly when it comes to controlling hand function. Movement-related brain activity might serve as a complementary bio-signal for motor control of hand prosthesis. Methods: We introduced a methodology to implant a cortical interface without direct exposure of the brain surface in an upper-limb amputee. This bi-directional interface enabled us to explore the cortical physiology following long-term transhumeral amputation. In addition, we investigated neurofeedback of electrocorticographic brain activity related to the patient’s motor imagery to open his missing hand, i.e. phantom hand movement, for real-time control of a virtual hand prosthesis.Results: Both event-related brain potentials and cortical stimulation revealed mutually overlapping cortical representations of the phantom hand. Phantom hand movements could be robustly classified and the patient required only three training sessions to gain reliable control of the virtual hand prosthesis in an online closed-loop paradigm that discriminated between hand opening and rest. Conclusion: Epidural implants may constitute a powerful and safe alternative communication pathway between the brain and external devices for upper-limb amputees, thereby facilitating the integrated use of different signal sources for more intuitive and specific control of multi-functional devices in clinical use.

  12. Short latency hand movement classification based on surface EMG spectrogram with PCA.

    Science.gov (United States)

    Xiaolong Zhai; Jelfs, Beth; Chan, Rosa H M; Chung Tin

    2016-08-01

    Hand gesture recognition from forearm surface electromyography (sEMG) is an active research field in the development of motor prosthesis. Studies have shown that classification accuracy and efficiency is highly dependent on the features extracted from the EMG. In this paper, we show that EMG spectrograms are a particularly effective feature for discriminating multiple classes of hand gesture when subjected to principal component analysis for dimensionality reduction. We tested our method on the Ninapro database which includes sEMG data (12 channels) of 40 subjects performing 50 different hand movements. Our results demonstrate improved classification accuracy (by ~10%) over purely time domain features for 50 different hand movements, including small finger movements and different levels of force exertion. Our method has also reduced the error rate (by ~12%) at the transition phase of gestures which could improve robustness of gesture recognition when continuous classification from sEMG is required.

  13. Analysis of EEG signal by Flicker Noise Spectroscopy: Identification of right/left hand movement imagination

    CERN Document Server

    Broniec, Anna

    2014-01-01

    Flicker Noise Spectroscopy (FNS) has been used for the analysis of electroencephalography (EEG) signal related to the movement imagination. The analysis of sensorimotor rhythms in time-frequency maps reveals the event-related desynchronization (ERD) and the post-movement event-related synchronization (ERS), observed mainly in the contralateral hemisphere to the hand moved for the motor imagery. The signal has been parameterized in accordance with FNS method. The significant changes of the FNS parameters, at the time when the subject imagines the movement, have been observed. The analysis of these parameters allows to distinguish between imagination of right and left hands movement. Our study shows that the flicker-noise spectroscopy can be an alternative method of analyzing EEG signal related to the imagination of movement in terms of a potential application in the brain-computer interface (BCI).

  14. Eye and Hand Movements during Reconstruction of Spatial Memory

    Directory of Open Access Journals (Sweden)

    Melanie Rose Burke

    2012-05-01

    Full Text Available Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (eg, Awh et al 2006, Trends in Cognitive Sciences 10, 124–130. This study explored the role of spatial attention and visual search in an adapted Corsi spatial memory task. Eye movements and touch responses were recorded from participants who recalled locations (signalled by colour or shape change from an array presented either simultaneously or sequentially. The time delay between target presentation and recall (0, 5, or 10s and the number of locations to be remembered (2–5 were also manipulated. Analysis of the response phase revealed subjects were less accurate (touch data and fixated longer (eye data when responding to sequentially presented targets. Fixation duration was also influenced by whether spatial location was initially signalled by colour or shape change. We conclude that attention and temporal delays during retention of a target play a minor role in motor behaviour during a corsi spatial memory task. In contrast, the type of memory required (ie, location and/or memory and number of items plays a key role on subject performance and behaviour.

  15. Time-dependent adaptations to posture and movement characteristics during the development of repetitive reaching induced fatigue.

    Science.gov (United States)

    Fuller, Jason R; Fung, Joyce; Côté, Julie N

    2011-05-01

    Repetitive movements are common to many daily activities but often lead to the development of fatigue. We have previously shown that fatigue leads to changes in tridimensional spatial characteristics of the whole body. However, temporal aspects of these posture and movement adaptations have yet to be investigated. Healthy subjects (N = 14) performed a continuous reaching task by pointing between two targets placed at shoulder height, at 100 and 30% arm's length, anterior to the subject's midline until fatigue (assessed using the Borg CR-10 scale). Whole body kinematics and upper Trapezius EMG were recorded and analyzed at 1-min intervals to document the progression of fatigue on outcome variables. For all upper limb and postural variables analyzed, changes began to occur approximately midway to fatigue and were followed by an increase in Trapezius activity from baseline. Reach-to-reach variability of joint average positions and range of motion (ROM) increased in multiple directions for shoulder and elbow parameters. Reach-to-reach variability of the center-of-mass ROM also increased in several directions. Changes were also observed in within-movement inter-segmental timing. The peak velocities of elbow and endpoint occurred closer together in time during fatigue while the shoulder peak velocity occurrence showed a greater reach-to-reach variability. Our results suggest that the effects of fatigue on repetitive movement kinematics can be observed across three temporal dimensions of the task: (1) within individual movements, (2) from one movement to the next, and (3) as fatigue develops. Each observed change is discussed as a potential contributor to task-specific control strategies to prolong task performance.

  16. Constant error in aiming movements without visual feedback is higher in the preferred hand.

    Science.gov (United States)

    Lenhard, Alexandra; Hoffmann, Joachim

    2007-05-01

    There is convincing evidence for a left hand advantage for the spatial planning of aiming movements in right-handers. However, little is known about equivalent proficiency in left-handers. Therefore, 48 participants (24 right-handers and 24 left-handers) performed aiming movements of the hand without visual feedback. While the variable aiming error tended to be lower for the preferred hand, the constant aiming error was consistently lower for the non-preferred hand. Data are consistent with the idea of a spatial accuracy advantage for the controller of the non-preferred hand. Data from an ambidextrous participant suggest that this functional difference might be innate rather than acquired through practice.

  17. Excitability changes in the left primary motor cortex innervating the hand muscles induced during speech about hand or leg movements.

    Science.gov (United States)

    Onmyoji, Yusuke; Kubota, Shinji; Hirano, Masato; Tanaka, Megumi; Morishita, Takuya; Uehara, Kazumasa; Funase, Kozo

    2015-05-06

    In the present study, we used transcranial magnetic stimulation (TMS) to investigate the changes in the excitability of the left primary motor cortex (M1) innervating the hand muscles and in short-interval intracortical inhibition (SICI) during speech describing hand or leg movements. In experiment 1, we investigated the effects of the contents of speech on the amplitude of the motor evoked potentials (MEPs) induced during reading aloud and silent reading. In experiment 2, we repeated experiment 1 with an additional condition, the non-vocal oral movement (No-Voc OM) condition, and investigated the change in SICI induced in each condition using the paired TMS paradigm. The MEP observed in the reading aloud and No-Voc OM conditions exhibited significantly greater amplitudes than those seen in the silent reading conditions, irrespective of the content of the sentences spoken by the subjects or the timing of the TMS. There were no significant differences in SICI between the experimental conditions. Our findings suggest that the increased excitability of the left M1 hand area detected during speech was mainly caused by speech-related oral movements and the activation of language processing-related brain functions. The increased left M1 excitability was probably also mediated by neural mechanisms other than reduced SICI; i.e., disinhibition. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Kinematic analysis of hand movements after tendon repair surgery : a new assessment using drawing movements

    NARCIS (Netherlands)

    Stenekes, Martin W.; Nicolai, Jean-Philippe A.; Geertzen, Jan H. B.; Mulder, Theo

    2008-01-01

    Objective: Although several hand outcome tests exist to judge skill level after hand injury, currently none give insight into how tasks are performed by looking at kinematic parameters. In this article, the clinical value of analyzing kinematic parameters related to the drawing of a triangle on a gr

  19. An exploratory study to design a novel hand movement identification system.

    Science.gov (United States)

    Khezri, Mahdi; Jahed, Mehran

    2009-05-01

    Electromyogram signal (EMG) is an electrical manifestation of contractions of muscles. Surface EMG (sEMG) signal collected from the surface of skin has been used in diverse applications. One of its usages is in pattern recognition of hand prosthesis movements. The ability of current prosthesis devices has been generally limited to simple opening and closing tasks, minimizing their efficacy compared to natural hand capabilities. In order to extend the abilities and accuracy of prosthesis arm movements and performance, a novel sEMG pattern recognizing system is proposed. To extract more pertinent information we extracted sEMGs for selected hand movements. These features constitute our main knowledge of the signal for different hand movements. In this study, we investigated time domain, time-frequency domain and combination of these as a compound representation of sEMG signal's features to access required signal information. In order to implement pattern recognition of sEMG signals for various hand movements, two intelligent classifiers, namely artificial neural network (ANN) and fuzzy inference system (FIS), were utilized. The results indicate that our approach of using compound features with principle component analysis (PCA) as dimensionality reduction technique, and FIS as the classifier, provides the best performance for sEMG pattern recognition system.

  20. Classification of right-hand grasp movement based on EMOTIV Epoc+

    Science.gov (United States)

    Tobing, T. A. M. L.; Prawito, Wijaya, S. K.

    2017-07-01

    Combinations of BCT elements for right-hand grasp movement have been obtained, providing the average value of their classification accuracy. The aim of this study is to find a suitable combination for best classification accuracy of right-hand grasp movement based on EEG headset, EMOTIV Epoc+. There are three movement classifications: grasping hand, relax, and opening hand. These classifications take advantage of Event-Related Desynchronization (ERD) phenomenon that makes it possible to differ relaxation, imagery, and movement state from each other. The combinations of elements are the usage of Independent Component Analysis (ICA), spectrum analysis by Fast Fourier Transform (FFT), maximum mu and beta power with their frequency as features, and also classifier Probabilistic Neural Network (PNN) and Radial Basis Function (RBF). The average values of classification accuracy are ± 83% for training and ± 57% for testing. To have a better understanding of the signal quality recorded by EMOTIV Epoc+, the result of classification accuracy of left or right-hand grasping movement EEG signal (provided by Physionet) also be given, i.e.± 85% for training and ± 70% for testing. The comparison of accuracy value from each combination, experiment condition, and external EEG data are provided for the purpose of value analysis of classification accuracy.

  1. Movement Coordination in Psychotherapy: Synchrony of Hand Movements is Associated with Session Outcome. A Single-Case Study.

    Science.gov (United States)

    Ramseyer, Fabian; Tschacher, Wolfgang

    2016-04-01

    Previous work has shown that nonverbal behavior was associated with both session-level outcome and global outcome in psychotherapy. Nonverbal synchrony--here the coordination between patient's and psychotherapist's movement behavior--is a facet of nonverbal behavior that has recently been studied with video-based motion energy analysis (MEA). The present study aimed to replicate and extend these findings by using direct acquisition of movement data. In a single-case analysis, we monitored patient's and therapist's hand movements with a high-resolution accelerometric measurement system (Vitaport (r)). In addition to these behavioral data, both patient and therapist provided session-level ratings of various factors relevant to the psychotherapy process, which were assessed with post-session questionnaires. The patient-therapist coordination of hand movements, i.e. nonverbal synchrony, in (N = 27) sessions of this dyadic psychotherapy was positively associated with progress reported in post-session questionnaires. Sessions with good evaluations concerning the quality of therapeutic alliance were characterized by high movement coordination. Thus, accelerometric data of this therapy dyad confirmed previous findings gained through video analyses: The coordination of nonverbal behavior shown by patient and therapist was an indicator of beneficial processes occurring within sessions. This replication study showed that nonverbal synchrony embodies important aspects of the alliance. Its assessment and quantification may provide therapists important additional information on processes that usually occur outside conscious awareness, but that nevertheless influence core aspects of the therapy.

  2. Risk Assessment of Repetitive Movements in Olive Growing: Analysis of Annual Exposure Level Assessment Models with the OCRA Checklist.

    Science.gov (United States)

    Proto, A R; Zimbalatti, G

    2015-10-01

    In Italy, one of the main agricultural crops is represented by the cultivation of olive trees. Olive cultivation characterizes the Italian agricultural landscape and national agricultural economics. Italy is the world's second largest producer of olive oil. Because olive cultivation requires the largest labor force in southern Italy, the aim of this research was to assess the risk of biomechanical overload of the workers' upper limbs. The objective, therefore, was to determine the level of risk that workers are exposed to in each phase of the production process. In Calabria, the second most important region in Italy for both the production of olive oil and cultivated area, there are 113,907 olive farms (83% of all farms) and 250,000 workers. To evaluate the risk of repetitive movements, all of the work tasks performed by workers on 100 farms in Calabria were analyzed. A total of 430 workers were interviewed over the four-year research period. To evaluate the level of exposure to repetitive movements, the OCRA (occupational repetitive actions) checklist was adopted. This checklist was the primary analytical tool during the preliminary risk assessment and in a given working situation. The analysis suggested by the OCRA checklist starts with pre-assigned scores (increasing in value with intensification of risk) for each of four main risk factors and additional factors. Between 2010 and 2013, surveys were conducted using the OCRA checklist with the aim of verifying musculoskeletal risks. The results obtained from the study of 430 workers allowed us to identify the level of exposure to risk. This analysis was conducted in the workplace to examine in detail the repetitive movements performed by the workers. The research was divided into two phases: first to provide preliminary information on the different tasks performed in olive growing, and second to assign a percentage to each task of the total hours worked in a year. Based on the results, this method could well

  3. Gaze and hand position effects on finger-movement-related human brain activation.

    Science.gov (United States)

    Bédard, Patrick; Sanes, Jerome N

    2009-02-01

    Humans commonly use their hands to move and to interact with their environment by processing visual and proprioceptive information to determine the location of a goal-object and the initial hand position. It remains elusive, however, how the human brain fully uses this sensory information to generate accurate movements. In monkeys, it appears that frontal and parietal areas use and combine gaze and hand signals to generate movements, whereas in humans, prior work has separately assessed how the brain uses these two signals. Here we investigated whether and how the human brain integrates gaze orientation and hand position during simple visually triggered finger tapping. We hypothesized that parietal, frontal, and subcortical regions involved in movement production would also exhibit modulation of movement-related activation as a function of gaze and hand positions. We used functional MRI to measure brain activation while healthy young adults performed a visually cued finger movement and fixed gaze at each of three locations and held the arm in two different configurations. We found several areas that exhibited activation related to a mixture of these hand and gaze positions; these included the sensory-motor cortex, supramarginal gyrus, superior parietal lobule, superior frontal gyrus, anterior cingulate, and left cerebellum. We also found regions within the left insula, left cuneus, left midcingulate gyrus, left putamen, and right tempo-occipital junction with activation driven only by gaze orientation. Finally, clusters with hand position effects were found in the cerebellum bilaterally. Our results indicate that these areas integrate at least two signals to perform visual-motor actions and that these could be used to subserve sensory-motor transformations.

  4. Involuntary human hand movements due to FM radio waves in a moving van.

    Science.gov (United States)

    Huttunen, P; Savinainen, A; Hänninen, Osmo; Myllylä, R

    2011-06-01

    Finland TRACT Involuntary movements of hands in a moving van on a public road were studied to clarify the possible role of frequency modulated radio waves on driving. The signals were measured in a direct 2 km test segment of an international road during repeated drives to both directions. Test subjects (n=4) had an ability to sense radio frequency field intensity variations of the environment. They were sitting in a minivan with arm movement detectors in their hands. A potentiometer was used to register the hand movements to a computer which simultaneously collected data on the amplitude of the RF signal of the local FM tower 30 km distance at a frequency of about 100 MHz. Involuntary hand movements of the test subjects correlated with electromagnetic field, i.e. FM radio wave intensity measured. They reacted also on the place of a geomagnetic anomaly crossing the road, which was found on the basis of these recordings and confirmed by the public geological maps of the area.In conclusion, RF irradiation seems to affect the human hand reflexes of sensitive persons in a moving van along a normal public road which may have significance in traffic safety.

  5. Neural coupling of cooperative hand movements: a reflex and fMRI study.

    Science.gov (United States)

    Dietz, Volker; Macauda, Gianluca; Schrafl-Altermatt, Miriam; Wirz, Markus; Kloter, Evelyne; Michels, Lars

    2015-04-01

    The neural control of "cooperative" hand movements reflecting "opening a bottle" was explored in human subjects by electromyographic (EMG) and functional magnetic resonance imaging (fMRI) recordings. EMG responses to unilateral nonnoxious ulnar nerve stimulation were analyzed in the forearm muscles of both sides during dynamic movements against a torque applied by the right hand to a device which was compensated for by the left hand. For control, stimuli were applied while task was performed in a static/isometric mode and during bilateral synchronous pro-/supination movements. During the dynamic cooperative task, EMG responses to stimulations appeared in the right extensor and left flexor muscles, regardless of which side was stimulated. Under the control conditions, responses appeared only on the stimulated side. fMRI recordings showed a bilateral extra-activation and functional coupling of the secondary somatosensory cortex (S2) during the dynamic cooperative, but not during the control, tasks. This activation might reflect processing of shared cutaneous input during the cooperative task. Correspondingly, it is assumed that stimulation-induced unilateral volleys are processed in S2, leading to a release of EMG responses to both forearms. This indicates a task-specific neural coupling during cooperative hand movements, which has consequences for the rehabilitation of hand function in poststroke patients.

  6. Hand-held tools with complex kinematics are efficiently incorporated into movement planning and online control.

    Science.gov (United States)

    Baugh, Lee A; Hoe, Erica; Flanagan, J Randall

    2012-10-01

    Certain hand-held tools alter the mapping between hand motion and motion of the tool end point that must be controlled in order to perform a task. For example, when using a pool cue, the motion of the cue tip is reversed relative to the hand. Previous studies have shown that the time required to initiate a reaching movement (Fernandez-Ruiz J, Wong W, Armstrong IT, Flanagan JR. Behav Brain Res 219: 8-14, 2011), or correct an ongoing reaching movement (Gritsenko V, Kalaska JF. J Neurophysiol 104: 3084-3104, 2010), is prolonged when the mapping between hand motion and motion of a cursor controlled by the hand is reversed. Here we show that these time costs can be significantly reduced when the reversal is instantiated by a virtual hand-held tool. Participants grasped the near end of a virtual tool, consisting of a rod connecting two circles, and moved the end point to displayed targets. In the reversal condition, the rod translated through, and rotated about, a pivot point such that there was a left-right reversal between hand and end point motion. In the nonreversal control, the tool translated with the hand. As expected, when only the two circles were presented, movement initiation and correction times were much longer in the reversal condition. However, when full vision of the tool was provided, the reaction time cost was almost eliminated. These results indicate that tools with complex kinematics can be efficiently incorporated into sensorimotor control mechanisms used in movement planning and online control.

  7. Development of rotational movements, hand shaping, and accuracy in advance and withdrawal for the reach-to-eat movement in human infants aged 6-12 months.

    Science.gov (United States)

    Sacrey, Lori-Ann R; Karl, Jenni M; Whishaw, Ian Q

    2012-06-01

    The reach-to-eat movement, transport of a hand to grasp an object that is withdrawn and placed in the mouth, is amongst the earliest developing functional movements of human infants. The present longitudinal study is the first description of the maturation of hand-rotation, hand shaping, and accuracy associated with the advance and withdrawal phases of the movement. Eight infants, aged 6-12 months, and eight adults, were video recorded as they reached for familiar objects or food items. Hand, arm, and trunk movements were assessed frame-by-frame with the Skilled Reaching Rating Scale, previously developed for the assessment of adult reaching, and supplementary kinematic analysis. Reach-to-eat maturation was characterized by three changes. First, for advance, a simple open hand transport gradually matured to a movement associated with pronation and hand shaping of the digits for precision grasping. Second, for withdrawal to the mouth, a direct withdrawal movement gradually became associated with hand supination that oriented the target object to the mouth. Third, associated with the maturation of rotational movements, inaccurate and fragmented hand transport and withdrawal movements developed into precise targeting of the hand-to-object and object-to-mouth. Across the age range, there was a decrease in bimanual reaching and an increase in right handed reaching. The results are discussed in relation to the idea that the maturation of the reach-to-eat movement involves the development of rotational and shaping movements of the hand and visual and somatosensory guidance of a preferred hand.

  8. Classification of finger movements for the dexterous hand prosthesis control with surface electromyography.

    Science.gov (United States)

    Al-Timemy, Ali H; Bugmann, Guido; Escudero, Javier; Outram, Nicholas

    2013-05-01

    A method for the classification of finger movements for dexterous control of prosthetic hands is proposed. Previous research was mainly devoted to identify hand movements as these actions generate strong electromyography (EMG) signals recorded from the forearm. In contrast, in this paper, we assess the use of multichannel surface electromyography (sEMG) to classify individual and combined finger movements for dexterous prosthetic control. sEMG channels were recorded from ten intact-limbed and six below-elbow amputee persons. Offline processing was used to evaluate the classification performance. The results show that high classification accuracies can be achieved with a processing chain consisting of time domain-autoregression feature extraction, orthogonal fuzzy neighborhood discriminant analysis for feature reduction, and linear discriminant analysis for classification. We show that finger and thumb movements can be decoded accurately with high accuracy with latencies as short as 200 ms. Thumb abduction was decoded successfully with high accuracy for six amputee persons for the first time. We also found that subsets of six EMG channels provide accuracy values similar to those computed with the full set of EMG channels (98% accuracy over ten intact-limbed subjects for the classification of 15 classes of different finger movements and 90% accuracy over six amputee persons for the classification of 12 classes of individual finger movements). These accuracy values are higher than previous studies, whereas we typically employed half the number of EMG channels per identified movement.

  9. Different distal-proximal movement balances in right- and left-hand writing may hint at differential premotor cortex involvement.

    Science.gov (United States)

    Potgieser, A R E; de Jong, B M

    2011-12-01

    Right-handed people generally write with their right hand. Language expressed in script is thus performed with the hand also preferred for skilled motor tasks. This may suggest an efficient functional interaction between the language area of Broca and the adjacent ventral premotor cortex (PMv) in the left (dominant) hemisphere. Pilot observations suggested that distal movements are particularly implicated in cursive writing with the right hand and proximal movements in left-hand writing, which generated ideas concerning hemisphere-specific roles of PMv and dorsal premotor cortex (PMd). Now we examined upper-limb movements in 30 right-handed participants during right- and left-hand writing, respectively. Quantitative description of distal and proximal movements demonstrated a significant difference between movements in right- and left-hand writing (pwriting with the right hand, while proximal and distal movements similarly contributed to left-hand writing. Although differences between non-language drawings were not tested, we propose that the DME in right-hand writing may reflect functional dominance of PMv in the left hemisphere. More proximal movements in left-hand writing might be related to PMd dominance in right-hemisphere motor control, logically implicated in spatial visuomotor transformations as seen in reaching.

  10. Effects of Hand Proximity and Movement Direction in Spatial and Temporal Gap Discrimination

    Science.gov (United States)

    Wiemers, Michael; Fischer, Martin H.

    2016-01-01

    Previous research on the interplay between static manual postures and visual attention revealed enhanced visual selection near the hands (near-hand effect). During active movements there is also superior visual performance when moving toward compared to away from the stimulus (direction effect). The “modulated visual pathways” hypothesis argues that differential involvement of magno- and parvocellular visual processing streams causes the near-hand effect. The key finding supporting this hypothesis is an increase in temporal and a reduction in spatial processing in near-hand space (Gozli et al., 2012). Since this hypothesis has, so far, only been tested with static hand postures, we provide a conceptual replication of Gozli et al.’s (2012) result with moving hands, thus also probing the generality of the direction effect. Participants performed temporal or spatial gap discriminations while their right hand was moving below the display. In contrast to Gozli et al. (2012), temporal gap discrimination was superior at intermediate and not near hand proximity. In spatial gap discrimination, a direction effect without hand proximity effect suggests that pragmatic attentional maps overshadowed temporal/spatial processing biases for far/near-hand space. PMID:28018268

  11. Load Handling and Repetitive Movements Are Associated with Chronic Low Back Pain among Jute Mill Workers in India.

    Science.gov (United States)

    Goswami, S; Dasgupta, S; Samanta, A; Talukdar, G; Chanda, A; Ray Karmakar, P; Majumdar, A; Bhattacharya, D; Chakrabarti, A

    2016-01-01

    Introduction. WHO recognizes low back pain as one of the most important ergonomic stressors. Therefore, the present study was designed to find out the magnitude of the problem among jute mill workers in India and identify possible associations. Methodology. This cross-sectional workplace based study was conducted among eight (8) selected jute mills of India. Subjects with self-reported back pain for at least last 12 weeks were included and n = 717 male jute mill workers actively engaged in work entered the study and completed all assessments. Results. Among all participants 55% (n = 392) had current chronic low back pain. Age was an important association with subjects in the age group of 40-59 years more likely to have pain (p = 0.02, OR 1.44). Regarding ergonomic risk factors lifting of load of more than 20 kg (p = 0.04, OR 1.42) and repetitive movements of limbs (p = 0.03, OR 0.67) were significant associations of chronic low back pain. Conclusion. This study identified a significant prevalence of current chronic low back pain among jute mill workers. Regarding ergonomic risk factors the present study has identified two significant associations: lifting of load above 20 kg and repetitive movements of limbs. Therefore, this study has identified need for workplace interventions in this occupational group employing approximately 3,50,000 workers in India.

  12. Load Handling and Repetitive Movements Are Associated with Chronic Low Back Pain among Jute Mill Workers in India

    Directory of Open Access Journals (Sweden)

    S. Goswami

    2016-01-01

    Full Text Available Introduction. WHO recognizes low back pain as one of the most important ergonomic stressors. Therefore, the present study was designed to find out the magnitude of the problem among jute mill workers in India and identify possible associations. Methodology. This cross-sectional workplace based study was conducted among eight (8 selected jute mills of India. Subjects with self-reported back pain for at least last 12 weeks were included and n=717 male jute mill workers actively engaged in work entered the study and completed all assessments. Results. Among all participants 55% (n=392 had current chronic low back pain. Age was an important association with subjects in the age group of 40–59 years more likely to have pain (p=0.02, OR 1.44. Regarding ergonomic risk factors lifting of load of more than 20 kg (p=0.04, OR 1.42 and repetitive movements of limbs (p=0.03, OR 0.67 were significant associations of chronic low back pain. Conclusion. This study identified a significant prevalence of current chronic low back pain among jute mill workers. Regarding ergonomic risk factors the present study has identified two significant associations: lifting of load above 20 kg and repetitive movements of limbs. Therefore, this study has identified need for workplace interventions in this occupational group employing approximately 3,50,000 workers in India.

  13. Perception of hand movement by mirror reflection evokes brain activation in the motor cortex contralateral to a non-moving hand.

    Science.gov (United States)

    Debnath, Ranjan; Franz, Elizabeth A

    2016-08-01

    We investigated whether perception of hand movement via mirror reflection evokes activation in the motor cortex (M1) contralateral to the non-moving hand (the M1 ipsilateral to the moving hand). Continuous electroencephalography (EEG) was recorded from 14 participants while they performed unimanual extension-flexion hand movements in direct view and mirror view conditions. We measured the lateralized readiness potential (LRP) as a marker of M1 activation in both conditions. Both the direct and mirror view conditions produced LRPs, with the mirror view conditions revealing clear activation in M1 contralateral to the non-moving hand (ipsilateral to the moving hand) during both flexion and extension phases. This unambiguous demonstration of M1 activation in association with a non-moving hand (which is visually-perceived as moving), suggests that perception of movement can directly lead to M1 activation.

  14. Evaluation of stiffness and plastic deformation of active ceramic self-ligating bracket clips after repetitive opening and closure movements

    Directory of Open Access Journals (Sweden)

    Grace Kelly Martins Carneiro

    2015-08-01

    Full Text Available OBJECTIVE: The aim of this study was to assess whether repetitive opening and closure of self-ligating bracket clips can cause plastic deformation of the clip.METHODS: Three types of active/interactive ceramic self-ligating brackets (n = 20 were tested: In-Ovation C, Quicklear and WOW. A standardized controlled device performed 500 cycles of opening and closure movements of the bracket clip with proper instruments and techniques adapted as recommended by the manufacturer of each bracket type. Two tensile tests, one before and one after the repetitive cycles, were performed to assess the stiffness of the clips. To this end, a custom-made stainless steel 0.40 x 0.40 mm wire was inserted into the bracket slot and adapted to the universal testing machine (EMIC DL2000, after which measurements were recorded. On the loading portion of the loading-unloading curve of clips, the slope fitted a first-degree equation curve to determine the stiffness/deflection rate of the clip.RESULTS: The results of plastic deformation showed no significant difference among bracket types before and after the 500 cycles of opening and closure (p = 0.811. There were significant differences on stiffness among the three types of brackets (p = 0.005. The WOW bracket had higher mean values, whereas Quicklear bracket had lower values, regardless of the opening/closure cycle.CONCLUSION: Repetitive controlled opening and closure movements of the clip did not alter stiffness or cause plastic deformation.

  15. Infantile nystagmus syndrome is associated with inefficiency of goal-directed hand movements

    NARCIS (Netherlands)

    Liebrand-Schurink, J.; Cox, R.F.A.; Rens, G.H.M.B. van; Cillessen, A.H.N.; Meulenbroek, R.G.J.; Boonstra, F.N.

    2015-01-01

    Purpose.: The effect of infantile nystagmus syndrome (INS) on the efficiency of goal-directed hand movements was examined. Methods.: We recruited 37 children with INS and 65 control subjects with normal vision, aged 4 to 8 years. Participants performed horizontally-oriented, goal-directed cylinder d

  16. Infantile nystagmus syndrome is associated with inefficiency of goal-directed hand movements

    NARCIS (Netherlands)

    Liebrand-Schurink, Joyce; Cox, Ralf F A; van Rens, Ger H M B; Cillessen, Antonius H N; Meulenbroek, Ruud G J; Boonstra, F Nienke

    2015-01-01

    PURPOSE: The effect of infantile nystagmus syndrome (INS) on the efficiency of goal-directed hand movements was examined. METHODS: We recruited 37 children with INS and 65 control subjects with normal vision, aged 4 to 8 years. Participants performed horizontally-oriented, goal-directed cylinder dis

  17. 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…

  18. Reduction of Stereotypical Hand Movements in Girls with Rett Syndrome: Two Case Studies.

    Science.gov (United States)

    Lotan, Meir; Roth, Dana

    This study explains the characteristics and treatment of individuals with Rett Syndrome and presents two case studies that investigated the use of interventions in reducing stereotypical hand movements (SHM). The case studies involve two girls (ages 5 and 7) with Rett Syndrome who were enrolled in a special education school. Information was…

  19. 49 CFR 236.202 - Signal governing movements over hand-operated switch.

    Science.gov (United States)

    2010-10-01

    ... switch. 236.202 Section 236.202 Transportation Other Regulations Relating to Transportation (Continued...-operated switch. Signal governing movements over hand-operated switch in the facing direction shall display... over the switch in the normal and in the reverse position, the signal shall display its...

  20. Hand Gesture Based Wheelchair Movement Control for Disabled Person Using MEMS.

    Directory of Open Access Journals (Sweden)

    Prof. Vishal V. Pande,

    2014-04-01

    Full Text Available This paper is to develop a wheel chair control which is useful to the physically disabled person with his hand movement or his hand gesture recognition using Acceleration technology.Tremendous leaps have been made in the field of wheelchair technology. However, even these significant advances haven‟t been able to help quadriplegics navigate wheelchair unassisted.It is wheelchair which can be controlled by simple hand gestures. It employs a sensor which controls the wheelchair hand gestures made by the user and interprets the motion intended by user and moves accordingly.In Acceleration we have Acceleration sensor. When we change the direction, the sensor registers values are changed and that values are given to microcontroller. Depending on the direction of the Acceleration, microcontroller controls the wheel chair directions like LEFT, RIGHT, FRONT, and BACK. The aim of this paper is to implement wheel chair direction control with hand gesture reorganization. Keywords-

  1. 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.

  2. Safety of primed repetitive transcranial magnetic stimulation and modified constraint-induced movement therapy in a randomized controlled trial in pediatric hemiparesis.

    Science.gov (United States)

    Gillick, Bernadette T; Krach, Linda E; Feyma, Tim; Rich, Tonya L; Moberg, Kelli; Menk, Jeremiah; Cassidy, Jessica; Kimberley, Teresa; Carey, James R

    2015-04-01

    To investigate the safety of combining a 6-Hz primed low-frequency repetitive transcranial magnetic stimulation (rTMS) intervention in the contralesional hemisphere with a modified constraint-induced movement therapy (mCIMT) program in children with congenital hemiparesis. Phase 1 randomized, double-blinded, placebo-controlled pretest/posttest trial. University academic facility and pediatric specialty hospital. Subjects (N = 19; age range, 8-17 y) with congenital hemiparesis caused by ischemic stroke or periventricular leukomalacia. No subject withdrew because of adverse events. All subjects included completed the study. Subjects were randomized to 1 of 2 groups: either real rTMS plus mCIMT (n = 10) or sham rTMS plus mCIMT (n = 9). Adverse events, physician assessment, ipsilateral hand function, stereognosis, cognitive function, subject report of symptoms assessment, and subject questionnaire. No major adverse events occurred. Minor adverse events were found in both groups. The most common events were headaches (real: 50%, sham: 89%; P = .14) and cast irritation (real: 30%, sham: 44%; P = .65). No differences between groups in secondary cognitive and unaffected hand motor measures were found. Primed rTMS can be used safely with mCIMT in congenital hemiparesis. We provide new information on the use of rTMS in combination with mCIMT in children. These findings could be useful in research and future clinical applications in advancing function in congenital hemiparesis. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  3. Brain network analysis of EEG functional connectivity during imagery hand movements.

    Science.gov (United States)

    Demuru, Matteo; Fara, Francesca; Fraschini, Matteo

    2013-12-01

    The characterization of human neural activity during imaginary movement tasks represent an important challenge in order to develop effective applications that allow the control of a machine. Yet methods based on brain network analysis of functional connectivity have been scarcely investigated. As a result we use graph theoretic methods to investigate the functional connectivity and brain network measures in order to characterize imagery hand movements in a set of healthy subjects. The results of the present study show that functional connectivity analysis and minimum spanning tree (MST) parameters allow to successfully discriminate between imagery hand movements (both right and left) and resting state conditions. In conclusion, this paper shows that brain network analysis of EEG functional connectivity could represent an efficient alternative to more classical local activation based approaches. Furthermore, it also suggests the shift toward methods based on the characterization of a limited set of fundamental functional connections that disclose salient network topological features.

  4. Epilepsia partialis continua with dystonic hand movement in a patient with a malformation of cortical development.

    Science.gov (United States)

    Zyss, Julie; Xie-Brustolin, Jing; Ryvlin, Philippe; Peysson, Stéphane; Beschet, Albert; Sappey-Marinier, Dominique; Hermier, Marc; Thobois, Stéphane

    2007-09-15

    Malformations of cortical development (MCD) with polymicrogyria and schizencephaly are due to abnormal cortical organization and usually manifest by intractable epilepsy and mental retardation. Epileptical activity is often hard to register and focal dystonia associated with such MCD has previously been described but without any metabolic imaging. We report here a 46-year-old man presenting with late-onset atypical abnormal movements of his left hand associated with right central region MCD. To demonstrate the involvement of an epileptical focus, we performed [(18)F]FDG-PET and fMRI both before and after a single dose of clobazam and diazepam, respectively. Characteristics of the abnormal hand movements, clinical response to the medication, and the result of the [(18)F]FDG-PET and fMRI investigations all favor the diagnosis of epilepsia partialis continua. We conclude that the dystonic movement is part of the partial seizure.

  5. Flexible, task-dependent use of sensory feedback to control hand movements.

    Science.gov (United States)

    Knill, David C; Bondada, Amulya; Chhabra, Manu

    2011-01-26

    We tested whether changing accuracy demands for simple pointing movements leads humans to adjust the feedback control laws that map sensory signals from the moving hand to motor commands. Subjects made repeated pointing movements in a virtual environment to touch a button whose shape varied randomly from trial to trial-between squares, rectangles oriented perpendicular to the movement path, and rectangles oriented parallel to the movement path. Subjects performed the task on a horizontal table but saw the target configuration and a virtual rendering of their pointing finger through a mirror mounted between a monitor and the table. On one-third of trials, the position of the virtual finger was perturbed by ±1 cm either in the movement direction or perpendicular to the movement direction when the finger passed behind an occluder. Subjects corrected quickly for the perturbations despite not consciously noticing them; however, they corrected almost twice as much for perturbations aligned with the narrow dimension of a target than for perturbations aligned with the long dimension. These changes in apparent feedback gain appeared in the kinematic trajectories soon after the time of the perturbations, indicating that they reflect differences in the feedback control law used throughout the duration of movements. The results indicate that the brain adjusts its feedback control law for individual movements "on demand" to fit task demands. Simulations of optimal control laws for a two-joint arm show that accuracy demands alone, coupled with signal-dependent noise, lead to qualitatively the same behavior.

  6. Acquisition and Analysis of EMG Signals to Recognize Multiple Hand Movements for Prosthetic Applications

    Directory of Open Access Journals (Sweden)

    Giuseppina Gini

    2012-01-01

    Full Text Available One of the main problems in developing active prosthesis is how to control them in a natural way. In order to increase the effectiveness of hand prostheses there is a need in better exploiting electromyography (EMG signals. After an analysis of the movements necessary for grasping, we individuated five movements for the wrist-hand mobility. Then we designed the basic electronics and software for the acquisition and the analysis of the EMG signals. We built a small size electronic device capable of registering them that can be integrated into a hand prosthesis. Among all the numerous muscles that move the fingers, we have chosen the ones in the forearm and positioned only two electrodes. To recognize the operation, we developed a classification system, using a novel integration of Artificial Neural Networks (ANN and wavelet features.

  7. Illusory movements of a phantom hand grade with the duration and magnitude of motor commands.

    Science.gov (United States)

    Walsh, Lee D; Gandevia, Simon C; Taylor, Janet L

    2010-04-15

    The senses of limb movement and position are critical for accurate control of movement. Recent studies show that central signals of motor command contribute to the sense of limb position but it is not clear whether such signals influence the distinctly different sense of limb movement. Nine subjects participated in two experiments in which we inflated a cuff around their upper arm to produce an ischaemic block, paralysing and anaesthetising the forearm, wrist and hand. This produces an experimental phantom wrist and hand. With their arm hidden from view subjects were asked to make voluntary efforts with their blocked wrist. In the first experiment, efforts were 20 and 40% of maximum and were 2 and 4 s in duration. The second experiment used 1 and 5 s efforts of 5 and 50% of maximum. Subjects signalled perceived movements of their phantom wrist using a pointer. All subjects reported clear perceptions of movement of their phantom hand for all levels and durations of effort. On average, subjects perceived their phantom wrist to move between 16.4 +/- 3.3 deg (mean +/- 95% confidence interval (CI)) and 30.2 +/- 5.4 deg in the first experiment and between 10.3 +/- 3.5 and 38.6 +/- 6.7 deg in the second. The velocity of the movements and total displacement of the phantom graded with the level of effort, and the total displacement also graded with duration. Hence, we have shown that motor command signals have a novel proprioceptive role in the perception of movement of human joints.

  8. Decoding individual finger movements from one hand using human EEG signals.

    Directory of Open Access Journals (Sweden)

    Ke Liao

    Full Text Available Brain computer interface (BCI is an assistive technology, which decodes neurophysiological signals generated by the human brain and translates them into control signals to control external devices, e.g., wheelchairs. One problem challenging noninvasive BCI technologies is the limited control dimensions from decoding movements of, mainly, large body parts, e.g., upper and lower limbs. It has been reported that complicated dexterous functions, i.e., finger movements, can be decoded in electrocorticography (ECoG signals, while it remains unclear whether noninvasive electroencephalography (EEG signals also have sufficient information to decode the same type of movements. Phenomena of broadband power increase and low-frequency-band power decrease were observed in EEG in the present study, when EEG power spectra were decomposed by a principal component analysis (PCA. These movement-related spectral structures and their changes caused by finger movements in EEG are consistent with observations in previous ECoG study, as well as the results from ECoG data in the present study. The average decoding accuracy of 77.11% over all subjects was obtained in classifying each pair of fingers from one hand using movement-related spectral changes as features to be decoded using a support vector machine (SVM classifier. The average decoding accuracy in three epilepsy patients using ECoG data was 91.28% with the similarly obtained features and same classifier. Both decoding accuracies of EEG and ECoG are significantly higher than the empirical guessing level (51.26% in all subjects (p<0.05. The present study suggests the similar movement-related spectral changes in EEG as in ECoG, and demonstrates the feasibility of discriminating finger movements from one hand using EEG. These findings are promising to facilitate the development of BCIs with rich control signals using noninvasive technologies.

  9. A key region in the human parietal cortex for processing proprioceptive hand feedback during reaching movements.

    Science.gov (United States)

    Reichenbach, Alexandra; Thielscher, Axel; Peer, Angelika; Bülthoff, Heinrich H; Bresciani, Jean-Pierre

    2014-01-01

    Seemingly effortless, we adjust our movements to continuously changing environments. After initiation of a goal-directed movement, the motor command is under constant control of sensory feedback loops. The main sensory signals contributing to movement control are vision and proprioception. Recent neuroimaging studies have focused mainly on identifying the parts of the posterior parietal cortex (PPC) that contribute to visually guided movements. We used event-related TMS and force perturbations of the reaching hand to test whether the same sub-regions of the left PPC contribute to the processing of proprioceptive-only and of multi-sensory information about hand position when reaching for a visual target. TMS over two distinct stimulation sites elicited differential effects: TMS applied over the posterior part of the medial intraparietal sulcus (mIPS) compromised reaching accuracy when proprioception was the only sensory information available for correcting the reaching error. When visual feedback of the hand was available, TMS over the anterior intraparietal sulcus (aIPS) prolonged reaching time. Our results show for the first time the causal involvement of the posterior mIPS in processing proprioceptive feedback for online reaching control, and demonstrate that distinct cortical areas process proprioceptive-only and multi-sensory information for fast feedback corrections.

  10. The resonant component of human physiological hand tremor is altered by slow voluntary movements.

    Science.gov (United States)

    Lakie, Martin; Vernooij, Carlijn A; Osborne, Timothy M; Reynolds, Raymond F

    2012-05-15

    Limb resonance imparts a characteristic spectrum to hand tremor. Movement will alter the resonance. We have examined the consequences of this change. Rectified forearm extensor muscle EMG and physiological hand tremor were recorded. In postural conditions the EMG spectrum is relatively flat whereas the acceleration spectrum is sharply peaked. Consequently, the gain between EMG and acceleration is maximal at the frequency where the tremor is largest (∼8 Hz). The shape of the gain curve implies mechanical resonance. Substantial alterations in posture do not significantly change the characteristics of the tremor or the shape or size of the gain curve. By contrast, slow or moderately paced voluntary wrist flexion–extension movements dramatically increase the hand tremor size and lower its peak frequency. These changes in size and frequency of the tremor cannot be attributed to changes in the EMG. Instead they reflect a very large change in the size and shape of the gain curve relating EMG to acceleration. The gain becomes larger and the peak moves to a lower frequency (∼6 Hz). We suggest that a movement-related (thixotropic) alteration in resonant properties of the wrist provides a simple explanation for these changes. The mechanism is illustrated by a model. Our new findings confirm that resonance plays a major role in wrist tremor. We also demonstrate that muscles operate very differently under postural and dynamic conditions. The different coupling between EMG and movement in posture and when moving must pose a considerable challenge for neural predictive control of skeletal muscles.

  11. Robotic Assistance by Impedance Compensation for Hand Movements While Manual Welding.

    Science.gov (United States)

    Erden, Mustafa Suphi; Billard, Aude

    2016-11-01

    In this paper, we present a robotic assistance scheme which allows for impedance compensation with stiffness, damping, and mass parameters for hand manipulation tasks and we apply it to manual welding. The impedance compensation does not assume a preprogrammed hand trajectory. Rather, the intention of the human for the hand movement is estimated in real time using a smooth Kalman filter. The movement is restricted by compensatory virtual impedance in the directions perpendicular to the estimated direction of movement. With airbrush painting experiments, we test three sets of values for the impedance parameters as inspired from impedance measurements with manual welding. We apply the best of the tested sets for assistance in manual welding and perform welding experiments with professional and novice welders. We contrast three conditions: 1) welding with the robot's assistance; 2) with the robot when the robot is passive; and 3) welding without the robot. We demonstrate the effectiveness of the assistance through quantitative measures of both task performance and perceived user's satisfaction. The performance of both the novice and professional welders improves significantly with robotic assistance compared to welding with a passive robot. The assessment of user satisfaction shows that all novice and most professional welders appreciate the robotic assistance as it suppresses the tremors in the directions perpendicular to the movement for welding.

  12. Reorganization and enhanced functional connectivity of motor areas in repetitive ankle movements after training in locomotor attention.

    Science.gov (United States)

    Sacco, Katiuscia; Katiuscia, Sacco; Cauda, Franco; Franco, Cauda; D'Agata, Federico; Federico, D'Agata; Mate, Davide; Davide, Mate; Duca, Sergio; Sergio, Duca; Geminiani, Giuliano; Giuliano, Geminiani

    2009-11-10

    We examined the functional changes in the activity of the cerebral areas involved in motor tasks, prior to and following a 1-week period of locomotor attention training consisting of physical and mental practice, in normal subjects. In a previous study, we examined the effect of the same kind of training on motor circuits using an fMRI paradigm of motor imagery. In this work, we investigated whether the expanded activations found in the previous study were present also using an overt foot motor task consisting of ankle dorsiflexion; a control task requiring hand movements was also administered. In this article, we also discuss the changes in functional connectivity between the pretraining and posttraining conditions during foot movements. The foot task showed a posttraining reorganization of the sensorimotor areas, which is in line with earlier studies on lower limb motor learning, while the control hand movement task only produced a modification in the left premotor cortex. These results confirm the effect of training on functional reorganization and underline its task specificity. After training, we also observed enhanced connectivity in the sensorimotor areas, suggesting that functional connectivity of the sensorimotor network can be modulated by focusing attention on the movements involved in ambulation.

  13. Unintended hand movements after abrupt cessation of variable and constant opposing forces.

    Science.gov (United States)

    Rapp, K; Heuer, H

    2013-04-16

    Humans are highly efficient in moving in a world of variable resistive forces which result, e.g., from different masses of objects or different directions of movements relative to gravity. However, the underlying mechanisms are challenged when an opposing force is suddenly removed. The resulting involuntary movements are known as accident risks in everyday life. We studied their characteristics upon abrupt cessations of opposing forces of 1, 2, and 4N which were presented in a series of variable or constant forces. The characteristics of the involuntary hand movements are largely determined by the mechanical impedance of the limb. The involuntary movements are oscillatory in nature, and their amplitude increases with stronger opposing force. Limb impedance is modulated both in a reactive and in an anticipatory manner. The reactive modulation occurs during each involuntary movement as a consequence of the neural responses elicited by the rapid limb acceleration consequent upon the cessation of the opposing force. Anticipatory modulation of limb impedance may serve to produce similar involuntary movements in spite of different opposing forces. The modulation is thus stronger with variable forces, where differences between resulting involuntary movements can be experienced more easily, than with constant forces.

  14. 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…

  15. Somatotopic reorganization of hand representation in bilateral arm amputees with or without special foot movement skill.

    Science.gov (United States)

    Yu, Xiao Jing; He, Hong Jian; Zhang, Qiao Wei; Zhao, Feng; Zee, Chi Shing; Zhang, Shi Zheng; Gong, Xiang Yang

    2014-02-10

    Bilateral arm amputees usually are excellent foot users. To explore the plasticity of the primary motor cortex in upper-extremities amputees and to determine if the acquisition of special foot movement skill is related with the bilateral hand amputation, we studied the primary motor cortex by using combined task and resting state functional magnetic resonance imaging (fMRI). We investigated 6 bilateral arm amputees with or without special foot movement skill. In the task fMRI study, we found that toe tapping of all the amputees activated the bilateral hand area, including cases without special foot skill. In addition, cases without special foot skill mainly activated the precentral gyrus, which differed from those with more adept foot motor skill who activated both the precentral and postcentral gyri. To further understand the plasticity of the hand area, the resting state functional connectivity was investigated between the foot and hand regions. One-tailed two-sample t-test suggested that the connections between two areas became significantly stronger in the amputee group. Our study demonstrates that hand region of the cortex does not remain 'silent' after bilateral arm amputation, but rather is recruited by other modalities such as adjacent or nonadjacent cortexes to process motor information in a functionally relevant manner. From the data presented, it seems that the bilateral arm amputees have a strong potential to develop new skills in their remaining extremities and practice may further enhance this potential.

  16. Decoding hand movement velocity from electroencephalogram signals during a drawing task

    Directory of Open Access Journals (Sweden)

    Gu Zhenghui

    2010-10-01

    Full Text Available Abstract Background Decoding neural activities associated with limb movements is the key of motor prosthesis control. So far, most of these studies have been based on invasive approaches. Nevertheless, a few researchers have decoded kinematic parameters of single hand in non-invasive ways such as magnetoencephalogram (MEG and electroencephalogram (EEG. Regarding these EEG studies, center-out reaching tasks have been employed. Yet whether hand velocity can be decoded using EEG recorded during a self-routed drawing task is unclear. Methods Here we collected whole-scalp EEG data of five subjects during a sequential 4-directional drawing task, and employed spatial filtering algorithms to extract the amplitude and power features of EEG in multiple frequency bands. From these features, we reconstructed hand movement velocity by Kalman filtering and a smoothing algorithm. Results The average Pearson correlation coefficients between the measured and the decoded velocities are 0.37 for the horizontal dimension and 0.24 for the vertical dimension. The channels on motor, posterior parietal and occipital areas are most involved for the decoding of hand velocity. By comparing the decoding performance of the features from different frequency bands, we found that not only slow potentials in 0.1-4 Hz band but also oscillatory rhythms in 24-28 Hz band may carry the information of hand velocity. Conclusions These results provide another support to neural control of motor prosthesis based on EEG signals and proper decoding methods.

  17. Decoding individual finger movements from one hand using human EEG signals.

    Science.gov (United States)

    Liao, Ke; Xiao, Ran; Gonzalez, Jania; Ding, Lei

    2014-01-01

    Brain computer interface (BCI) is an assistive technology, which decodes neurophysiological signals generated by the human brain and translates them into control signals to control external devices, e.g., wheelchairs. One problem challenging noninvasive BCI technologies is the limited control dimensions from decoding movements of, mainly, large body parts, e.g., upper and lower limbs. It has been reported that complicated dexterous functions, i.e., finger movements, can be decoded in electrocorticography (ECoG) signals, while it remains unclear whether noninvasive electroencephalography (EEG) signals also have sufficient information to decode the same type of movements. Phenomena of broadband power increase and low-frequency-band power decrease were observed in EEG in the present study, when EEG power spectra were decomposed by a principal component analysis (PCA). These movement-related spectral structures and their changes caused by finger movements in EEG are consistent with observations in previous ECoG study, as well as the results from ECoG data in the present study. The average decoding accuracy of 77.11% over all subjects was obtained in classifying each pair of fingers from one hand using movement-related spectral changes as features to be decoded using a support vector machine (SVM) classifier. The average decoding accuracy in three epilepsy patients using ECoG data was 91.28% with the similarly obtained features and same classifier. Both decoding accuracies of EEG and ECoG are significantly higher than the empirical guessing level (51.26%) in all subjects (pmovement-related spectral changes in EEG as in ECoG, and demonstrates the feasibility of discriminating finger movements from one hand using EEG. These findings are promising to facilitate the development of BCIs with rich control signals using noninvasive technologies.

  18. Is trichotillomania a stereotypic movement disorder? An analysis of body-focused repetitive behaviors in people with hair-pulling.

    Science.gov (United States)

    Stein, Dan J; Flessner, Christopher A; Franklin, Martin; Keuthen, Nancy J; Lochner, Christine; Woods, Douglas W

    2008-01-01

    Stereotypic movement disorder (SMD) is characterized by nonfunctional repetitive movements, is typically diagnosed in people with intellectual disability, and by definition excludes people with trichotillomania (TTM). Nevertheless, hair-pulling may be one of a number of body-focused repetitive behaviors (BFRBs) that are seen in the general population. Comorbidity of symptoms might support the idea that they are indicative of an underlying stereotypic disorder, and we therefore explored their frequency in people with hair-pulling. Participants were recruited with the help of the Trichotillomania Learning Center, the largest advocacy group for people with hair-pulling. Participants completed a self-report survey on the Internet, which included questions about the presence of both hair-pulling and other BFRBs. Measures included the Massachusetts General Hospital Hairpulling Scale (MGH-HS), the Milwaukee Inventory for Subtypes of Trichotillomania-Adult Version (MIST-A), the Depression and Anxiety Stress Scale (DASS), and the Sheehan Disability Scale (SDS). The majority of participants with hair-pulling (70%) report the presence of other BFRBs, most commonly skin-picking and nail-biting. There were particularly strong associations between the total number of BFRBs and increased scores on ratings of focused hair-pulling, depression, anxiety, stress, and functional impairment. Similar results were found in participants who met more rigorous criteria for trichotillomania. This study is limited by its self-report nature, and by the lack of detailed information on the phenomenology of comorbid BFRBs. While further nosological research is needed, the high rates of these behaviors in people with hair-pulling, and their association with increased disability, is consistent with previous clinical observations, and supports the argument that trichotillomania can usefully be conceptualized as a stereotypic disorder. Speculatively, this argument may be especially valid in

  19. Hand movement deviations in a visual search task with cross modal cuing

    Directory of Open Access Journals (Sweden)

    Hürol Aslan

    2007-01-01

    Full Text Available The purpose of this study is to demonstrate the cross-modal effects of an auditory organization on a visual search task and to investigate the influence of the level of detail in instructions describing or hinting at the associations between auditory stimuli and the possible locations of a visual target. In addition to measuring the participants’ reaction times, we paid special attention to tracking the hand movements toward the target. According to the results, the auditory stimuli unassociated with the target locations slightly –but significantly- increased the deviation of the hand movement from the path leading to the target location. The increase in the deviation depended on the degree of association between auditory stimuli and target locations, albeit not on the level of detail in the instructions about the task.

  20. Inhibitory control processes and the strategies that support them during hand and eye movements

    Directory of Open Access Journals (Sweden)

    Lauren Michelle Schmitt

    2016-12-01

    Full Text Available Background and Aims: Adaptive behavior depends on the ability to voluntarily suppress context-inappropriate behaviors, a process referred to as response inhibition. Stop Signal tests (SSTs are the most frequently studied paradigm used to assess response inhibition. Previous studies of SSTs have indicated that inhibitory control behavior can be explained using a common model in which GO and STOP processes are initiated independent from one and another, and the process that is completed first determines whether the behavior is elicited (GO process or terminated (STOP process. Consistent with this model, studies have indicated that individuals strategically delay their behaviors during SSTs in order to increase their stopping abilities. Despite being controlled by distinct neural systems, prior studies have largely documented similar inhibitory control performance across eye and hand movements. Though, no existing studies have compared the extent to which individuals strategically delay behavior across different effectors is not yet clear. Here, we compared the extent to which inhibitory control processes and the cognitive strategies that support them during oculomotor and manual motor behaviors. Methods: We examined 29 healthy individuals who performed parallel oculomotor and manual motor SSTs. Participants also completed a separate block of GO trials administered prior to the Stop Signal tasks to assess baseline reaction times for each effector and reaction time increases during interleaved GO trials of the SST. Results: Our results showed that stopping errors increased for both effectors as the interval between GO and STOP cues was increased (i.e., stop signal delay, but performance deteriorated more rapidly for eye compared to hand movements with increases in stop signal delay. During GO trials, participants delayed the initiation of their responses for each effector, and greater slowing of reaction times on GO trials was associated with

  1. Classification of Hand Grasp Kinetics and Types Using Movement-Related Cortical Potentials and EEG Rhythms

    Directory of Open Access Journals (Sweden)

    Mads Jochumsen

    2017-01-01

    Full Text Available Detection of single-trial movement intentions from EEG is paramount for brain-computer interfacing in neurorehabilitation. These movement intentions contain task-related information and if this is decoded, the neurorehabilitation could potentially be optimized. The aim of this study was to classify single-trial movement intentions associated with two levels of force and speed and three different grasp types using EEG rhythms and components of the movement-related cortical potential (MRCP as features. The feature importance was used to estimate encoding of discriminative information. Two data sets were used. 29 healthy subjects executed and imagined different hand movements, while EEG was recorded over the contralateral sensorimotor cortex. The following features were extracted: delta, theta, mu/alpha, beta, and gamma rhythms, readiness potential, negative slope, and motor potential of the MRCP. Sequential forward selection was performed, and classification was performed using linear discriminant analysis and support vector machines. Limited classification accuracies were obtained from the EEG rhythms and MRCP-components: 0.48±0.05 (grasp types, 0.41±0.07 (kinetic profiles, motor execution, and 0.39±0.08 (kinetic profiles, motor imagination. Delta activity contributed the most but all features provided discriminative information. These findings suggest that information from the entire EEG spectrum is needed to discriminate between task-related parameters from single-trial movement intentions.

  2. Hand movement deviations in a visual search task with cross modal cuing

    OpenAIRE

    Hürol Aslan; Asli Aslan

    2007-01-01

    The purpose of this study is to demonstrate the cross-modal effects of an auditory organization on a visual search task and to investigate the influence of the level of detail in instructions describing or hinting at the associations between auditory stimuli and the possible locations of a visual target. In addition to measuring the participants reaction times, we paid special attention to tracking the hand movements toward the target. According to the results, t...

  3. Involvement of secondary motor areas in externally-triggered single-finger movements of dominant and non-dominant hands

    Institute of Scientific and Technical Information of China (English)

    GU Yun; ZANG Yufeng; WENG Xuchu; JIA Fucang; LI Enzhong; WANG Jiangjun

    2003-01-01

    Whether the secondary motor areas are involved in simple voluntary movements remains controversial. Differences in the neural substrates of movements with the dominant and the non-dominant hands have not been well documented. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the hemodynamic response in the primary motor cortex (M1), supplementary motor area (SMA) and premotor cortex (PMC) in six healthy right-handed subjects while performing a visually-guided finger-tapping task with their dominant or non-dominant hands. Significant activation was observed in M1, SMA and PMC during this externally triggered simple voluntary movement task. While dominant hand movements only activated contralateral motor areas, non-domi- nant hand movements also activated ipsilateral SMA and PMC. The results provide strong evidence for the involvement of the secondary motor areas in simple voluntary movements, and also suggest that movements of the dominant hand primarily engage the contralateral secondary motor areas, whereas movements of the non-dominant hand engage bilateral secondary motor areas.

  4. A novel approach to recognize hand movements via sEMG patterns.

    Science.gov (United States)

    Khezri, Mahdi; Jahed, Mehran

    2007-01-01

    Electromyogram signal (EMG) is an electrical manifestation of contractions of muscles. Surface EMG (sEMG) signal collected form surface of the skin has been used in diverse applications. One of its usages is exploiting it in a pattern recognition system which evaluates and synthesizes hand prosthesis movements. The ability of current prosthesis has been limited in simple opening and closing that decreases the efficacy of these devices in contrary to natural hand. In order to extend the ability and accuracy of prosthesis arm movements and performance, a novel approach for sEMG pattern recognizing system is proposed. In order to have a relevant comparison, present and recent research for designing similar systems was re-evaluated. In this study, we investigate time domain, time-frequency domain and combination of these as a representation of sEMG signal feature for accessing signal information. For pattern recognition of sEMG signals for various hand movements, two intelligent classifiers, namely artificial neural network (ANN) and fuzzy inference system (FIS) were utilized. The results indicate that using compound features with principle component analysis (PCA), dimensionality reduction technique and fuzzy technique for classifier produces the best performance for sEMG pattern recognition system.

  5. A key region in the human parietal cortex for processing proprioceptive hand feedback during reaching movements

    DEFF Research Database (Denmark)

    Reichenbach, Alexandra; Thielscher, Axel; Peer, Angelika

    2014-01-01

    neuroimaging studies have focused mainly on identifying the parts of the posterior parietal cortex (PPC) that contribute to visually guided movements. We used event-related TMS and force perturbations of the reaching hand to test whether the same sub-regions of the left PPC contribute to the processing...... of proprioceptive-only and of multi-sensory information about hand position when reaching for a visual target. TMS over two distinct stimulation sites elicited differential effects: TMS applied over the posterior part of the medial intraparietal sulcus (mIPS) compromised reaching accuracy when proprioception...... was the only sensory information available for correcting the reaching error. When visual feedback of the hand was available, TMS over the anterior intraparietal sulcus (aIPS) prolonged reaching time. Our results show for the first time the causal involvement of the posterior mIPS in processing proprioceptive...

  6. Efficacy of Hand Behind Back Mobilization With Movement for Acute Shoulder Pain and Movement Impairment: A Randomized Controlled Trial.

    Science.gov (United States)

    Satpute, Kiran H; Bhandari, Prashant; Hall, Toby

    2015-06-01

    The aim of this study was to investigate the effects of hand-behind-back (HBB) Mulligan mobilization with movement (MWM) techniques on acute shoulder pain, impairment, and disability. This double-blind, randomized, controlled trial recruited 44 patients with acute shoulder pain and movement impairment presenting to an Indian general hospital. Participants were allocated to receive either MWM and exercise/hot pack (n = 22) or exercise/hot pack alone (n = 22). The average duration of symptoms was 4.1 and 4.7 weeks in the exercise and MWM groups, respectively. The primary outcome was HBB range of motion (ROM). Secondary variables were shoulder internal rotation ROM, pain intensity score, and shoulder disability identified by the shoulder pain and disability index. All variables were evaluated by a blinded assessor before and immediately after 9 treatment sessions over 3 weeks. Paired t tests revealed that both groups demonstrated statistically significant improvements (P < .001) with large effect sizes for all variables. However, for all variables, the MWM-with-exercise group showed significantly greater improvements (P < .05) than the exercise group. Hand-behind-back ROM showed a mean difference of 9.31° (95% confidence interval, 7.38-11.27), favoring greater improvement in the MWM-with-exercise group. In this study, the outcomes of patients with acute shoulder pain and disability receiving shoulder HBB MWM with exercise improved greater than those receiving exercise/hot packs alone. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

  7. The role of online visual feedback for the control of target-directed and allocentric hand movements.

    Science.gov (United States)

    Thaler, Lore; Goodale, Melvyn A

    2011-02-01

    Studies that have investigated how sensory feedback about the moving hand is used to control hand movements have relied on paradigms such as pointing or reaching that require subjects to acquire target locations. In the context of these target-directed tasks, it has been found repeatedly that the human sensory-motor system relies heavily on visual feedback to control the ongoing movement. This finding has been formalized within the framework of statistical optimality according to which different sources of sensory feedback are combined such as to minimize variance in sensory information during movement control. Importantly, however, many hand movements that people perform every day are not target-directed, but based on allocentric (object-centered) visual information. Examples of allocentric movements are gesture imitation, drawing, or copying. Here we tested if visual feedback about the moving hand is used in the same way to control target-directed and allocentric hand movements. The results show that visual feedback is used significantly more to reduce movement scatter in the target-directed as compared with the allocentric movement task. Furthermore, we found that differences in the use of visual feedback between target-directed and allocentric hand movements cannot be explained based on differences in uncertainty about the movement goal. We conclude that the role played by visual feedback for movement control is fundamentally different for target-directed and allocentric movements. The results suggest that current computational and neural models of sensorimotor control that are based entirely on data derived from target-directed paradigms have to be modified to accommodate performance in the allocentric tasks used in our experiments. As a consequence, the results cast doubt on the idea that models of sensorimotor control developed exclusively from data obtained in target-directed paradigms are also valid in the context of allocentric tasks, such as drawing

  8. Primed low-frequency repetitive transcranial magnetic stimulation and constraint-induced movement therapy in pediatric hemiparesis: a randomized controlled trial.

    Science.gov (United States)

    Gillick, Bernadette T; Krach, Linda E; Feyma, Tim; Rich, Tonya L; Moberg, Kelli; Thomas, William; Cassidy, Jessica M; Menk, Jeremiah; Carey, James R

    2014-01-01

    The aim of this study was to determine the feasibility and efficacy of five treatments of 6 Hz primed, low-frequency, repetitive transcranial magnetic stimulation (rTMS) combined with constraint-induced movement therapy (CIMT) to promote recovery of the paretic hand in children with congenital hemiparesis. Nineteen children with congenital hemiparesis aged between 8 and 17 years (10 males, nine females; mean age 10 years 10 months, SD 2 years 10 months; Manual Ability Classification Scale levels I-III) underwent five sessions of either real rTMS (n=10) or sham rTMS (n=9) alternated daily with CIMT. CIMT consisted of 13 days of continuous long-arm casting with five skin-check sessions. Each child received a total of 10 hours of one-to-one therapy. The primary outcome measure was the Assisting Hand Assessment (AHA) and the secondary outcome variables were the Canadian Occupational Performance Measure (COPM) and stereognosis. A Wilcoxon signed-rank sum test was used to analyze differences between pre- and post-test scores within the groups. Analysis of covariance was used to compute mean differences between groups adjusting for baseline. Fisher's exact test was used to compare individual change in AHA raw scores with the smallest detectable difference (SDD) of 4 points. All participants receiving treatment finished the study. Improvement in AHA differed significantly between groups (p=0.007). No significant differences in the secondary outcome measures were found. Eight out of 10 participants in the rTMS/CIMT group showed improvement greater than the SDD, but only two out of nine in the sham rTMS/CIMT group showed such improvement (p=0.023). No serious adverse events occurred. Primed, low-frequency rTMS combined with CIMT appears to be safe, feasible, and efficacious in pediatric hemiparesis. Larger clinical trials are now indicated. © 2013 Mac Keith Press.

  9. Stereotypical hand movements in 144 subjects with Rett syndrome from the population-based Australian database.

    Science.gov (United States)

    Carter, Philippa; Downs, Jenny; Bebbington, Ami; Williams, Simon; Jacoby, Peter; Kaufmann, Walter E; Leonard, Helen

    2010-02-15

    Stereotypic hand movements are a feature of Rett Syndrome but few studies have observed their nature systematically. Video data in familiar settings were obtained on subjects (n = 144) identified from an Australian population-based database. Hand stereotypies were demonstrated by most subjects (94.4%), 15 categories were observed and midline wringing was seen in approximately 60% of subjects. There was a median of two stereotypies per subject but this number decreased with age. Clapping and mouthing of hands were more prevalent in girls younger than 8 years and wringing was more prevalent in women 19 years or older. Clapping was commoner in those with p.R306C and early truncating mutations, and much rarer in those with p.R106W, p.R270X, p.R168X, and p.R255X. Stereotypies tended to be less frequent in those with more severe mutations. Otherwise, there were no clear relationships between our categories of stereotypies and mutation. Approximately a quarter each had predominantly right and left handed stereotypies and for the remaining half, no clear laterality was seen. Results were similar for all cases and when restricted to those with a pathogenic mutation. Hand stereotypies changed with increasing age but limited relationships with MECP2 mutations were identified.

  10. Improvements in hand function in adults with chronic tetraplegia following a multi-day 10Hz rTMS intervention combined with repetitive task practice

    Science.gov (United States)

    Gomes-Osman, Joyce; Field-Fote, Edelle C.

    2014-01-01

    Background and Purpose Evidence suggests the use of stimulation to increase corticomotor excitability improves hand function in persons with cervical spinal cord injury (SCI). We assessed effects of multi-day application of 10Hz repetitive transcranial magnetic stimulation (rTMS) applied to the corticomotor hand area combined with repetitive task practice (RTP) in participants with tetraplegia and neurologically healthy participants. Methods Using a double-blind randomized crossover design, 11 participants with chronic tetraplegia and 10 neurologically healthy participants received 3 sessions of 10Hz rTMS+RTP and 3 sessions of sham-rTMS+RTP to the corticomotor hand region controlling the weaker hand. RTMS was interleaved with RTP of a skilled motor task between pulse trains. Hand function (Jebsen-Taylor Hand Function Test [JTT], pinch, and grasp strength) and corticomotor excitability (amplitude of motor-evoked potential) were assessed prior to and following the rTMS+RTP and sham-rTMS+RTP phases. We assessed significance using paired t-tests on pre-post differences and effect sizes using standardized response mean (SRM). Results RTMS+RTP was associated with larger effect sizes compared to sham-rTMS+RTP for improvement in JTT for both the trained hand (SRM=0.85 and 0.42, respectively), non-trained hand (0.55, 0.31, respectively), and for grasp strength of the trained hand in the SCI group (0.67, 0.39, respectively) alone. Effect sizes for all other measures were small and there were no statistical between-condition differences in the outcomes assessed. Discussion and Conclusions RTMS may be a valuable adjunct to RTP for improving hand function in persons with tetraplegia. Higher stimulation dose (frequency, intensity, number of sessions) may be associated with larger effects. Video Abstract available (See Supplemental Digital Conent 1) for more insights from the authors. PMID:25415549

  11. Entropic Movement Complexity Reflects Subjective Creativity Rankings of Visualized Hand Motion Trajectories

    Science.gov (United States)

    Peng, Zhen; Braun, Daniel A.

    2015-01-01

    In a previous study we have shown that human motion trajectories can be characterized by translating continuous trajectories into symbol sequences with well-defined complexity measures. Here we test the hypothesis that the motion complexity individuals generate in their movements might be correlated to the degree of creativity assigned by a human observer to the visualized motion trajectories. We asked participants to generate 55 novel hand movement patterns in virtual reality, where each pattern had to be repeated 10 times in a row to ensure reproducibility. This allowed us to estimate a probability distribution over trajectories for each pattern. We assessed motion complexity not only by the previously proposed complexity measures on symbolic sequences, but we also propose two novel complexity measures that can be directly applied to the distributions over trajectories based on the frameworks of Gaussian Processes and Probabilistic Movement Primitives. In contrast to previous studies, these new methods allow computing complexities of individual motion patterns from very few sample trajectories. We compared the different complexity measures to how a group of independent jurors rank ordered the recorded motion trajectories according to their personal creativity judgment. We found three entropic complexity measures that correlate significantly with human creativity judgment and discuss differences between the measures. We also test whether these complexity measures correlate with individual creativity in divergent thinking tasks, but do not find any consistent correlation. Our results suggest that entropic complexity measures of hand motion may reveal domain-specific individual differences in kinesthetic creativity. PMID:26733896

  12. Motion as motivation: using repetitive flexion movements to stimulate the approach system.

    Science.gov (United States)

    Haeffel, Gerald J

    2011-12-01

    Research suggests that having a healthy approach system is critical for adaptive emotional functioning. The goal of the current study (n=186 undergraduates) was to determine the efficacy of an easy-to-disseminate and cost-efficient strategy for stimulating this system. The experiment tested the effects of repeated flexion movements (rFM) on approach system activation as measured by both self-report (BAS scales) and behavior. The results showed that rFM increased approach system motivation in men but not women. Men who completed the rFM task reported significantly greater levels of fun-seeking motivation than men in the control task. Moreover, the rFM task led to changes in actual behavior. Men who completed the rFM task exhibited significantly greater persistence on a difficult laboratory task than men in the control task. In contrast, women who completed the rFM task reported significantly lower levels of fun seeking and tended to exhibit less persistence on a difficult laboratory task than women in the control task. These results provide support for embodied theories of emotion as well as additional evidence for a gender difference in approach-avoidance tendencies.

  13. Changes in Timing and kinematics of goal directed eye-hand movements in early-stage Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Muilwijk Danya

    2013-01-01

    Full Text Available Abstract Objective Many daily activities involve intrinsic or extrinsic goal-directed eye and hand movements. An extensive visuomotor coordination network including nigro-striatal pathways is required for efficient timing and positioning of eyes and hands. The aim of this study was to investigate how Parkinson’s disease (PD affects eye-hand coordination in tasks with different cognitive complexity. Methods We used a touch screen, an eye-tracking device and a motion capturing system to quantify changes in eye-hand coordination in early-stage PD patients (H&Y  Results In the pro-tapping task, saccade initiation towards extrinsic goals was not impaired. However, in the dual planning and anti-tapping task initiation of saccades towards intrinsic goals was faster in PD patients. Hand movements were differently affected: initiation of the hand movement was only delayed in the pro-tapping and dual planning task. Overall, hand movements in PD patients were slower executed compared to controls. Interpretation Whereas initiation of saccades in an extrinsic goal-directed task (pro-tapping task is not affected, early stage PD patients have difficulty in suppressing reflexive saccades towards extrinsic goals in tasks where the endpoint is an intrinsic goal (e.g. dual planning and anti-tapping task. This is specific for eye movements, as hand movements have delayed responses in the pro-tapping and dual planning task. This suggests that reported impairment of the dorsolateral prefrontal cortex in early-stage PD patients affects only inhibition of eye movements. We conclude that timing and kinematics of eye and hand movements in visuomotor tasks are affected in PD patients. This result may have clinical significance by providing a behavioral marker for the early diagnosis of PD.

  14. Visuokinesthetic Perception of Hand Movement is Mediated by Cerebro–Cerebellar Interaction between the Left Cerebellum and Right Parietal Cortex

    Science.gov (United States)

    Hagura, Nobuhiro; Oouchida, Yutaka; Aramaki, Yu; Okada, Tomohisa; Matsumura, Michikazu; Sadato, Norihiro

    2009-01-01

    Combination of visual and kinesthetic information is essential to perceive bodily movements. We conducted behavioral and functional magnetic resonance imaging experiments to investigate the neuronal correlates of visuokinesthetic combination in perception of hand movement. Participants experienced illusory flexion movement of their hand elicited by tendon vibration while they viewed video-recorded flexion (congruent: CONG) or extension (incongruent: INCONG) motions of their hand. The amount of illusory experience was graded by the visual velocities only when visual information regarding hand motion was concordant with kinesthetic information (CONG). The left posterolateral cerebellum was specifically recruited under the CONG, and this left cerebellar activation was consistent for both left and right hands. The left cerebellar activity reflected the participants' intensity of illusory hand movement under the CONG, and we further showed that coupling of activity between the left cerebellum and the “right” parietal cortex emerges during this visuokinesthetic combination/perception. The “left” cerebellum, working with the anatomically connected high-order bodily region of the “right” parietal cortex, participates in online combination of exteroceptive (vision) and interoceptive (kinesthesia) information to perceive hand movement. The cerebro–cerebellar interaction may underlie updating of one's “body image,” when perceiving bodily movement from visual and kinesthetic information. PMID:18453537

  15. Altered brain functions in HIV positive patients free of HIV- associated neurocognitive disorders: A MRI study during unilateral hand movements

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    2015-03-01

    Full Text Available This paper aimed to investigate the brain activity of human immunodeficiency virus (HIV positive patients with normal cognition during unilateral hand movement and whether highly active antiretroviral therapy (HAART could affect the brain function. Functional magnetic resonance imaging (fMRI was performed for 60 HIV positive (HIV+ subjects and −42 healthy age-matched right-handed control subjects. Each subject was evaluated by the neuropsychological test and examined with fMRI during left and right hand movement tasks. HIV+ subjects showed greater activation in anterior cingulum, precuneus, occipital lobes, ipsilateral postcentral gyrus and contralateral cerebellum compared with control group during right hand movement task. However, during left hand movement no statistically significant difference was detected between these two groups. HAART medication for HIV+ subjects lowered the increased activity to normal level. Meanwhile patients receiving the regimen of zidovudine, lamivudine and efavirenz showed lower activity at bilateral caudate and ipsilateral inferior frontal gyrus in comparison with subjects receiving other HAART regimens. Therefore, HIV+ subjects demonstrated brain asymmetry in motor cortex, with increased activity present during right hand movement but absent during left hand movement. HAART proves effective in HIV+ subjects even with normal cognition and the specific regimen of HAART could prevent cerebral abnormal functions. Meanwhile, this study validates that during motor tasks, fMRI can detect the brain signal changes prior to the occurrences of other HIV- associated dysfunctions.

  16. Hand movements classification for myoelectric control system using adaptive resonance theory.

    Science.gov (United States)

    Jahani Fariman, H; Ahmad, Siti A; Hamiruce Marhaban, M; Alijan Ghasab, M; Chappell, Paul H

    2016-03-01

    This research proposes an exploratory study of a simple, accurate, and computationally efficient movement classification technique for prosthetic hand application. Surface myoelectric signals were acquired from the four muscles, namely, flexor carpi ulnaris, extensor carpi radialis, biceps brachii, and triceps brachii, of four normal-limb subjects. The signals were segmented, and the features were extracted with a new combined time-domain feature extraction method. Fuzzy C-means clustering method and scatter plot were used to evaluate the performance of the proposed multi-feature versus Hudgins' multi-feature. The movements were classified with a hybrid Adaptive Resonance Theory-based neural network. Comparative results indicate that the proposed hybrid classifier not only has good classification accuracy (89.09%) but also a significantly improved computation time.

  17. Effects of repetitive facilitative exercise with neuromuscular electrical stimulation, vibratory stimulation and repetitive transcranial magnetic stimulation of the hemiplegic hand in chronic stroke patients.

    Science.gov (United States)

    Etoh, Seiji; Noma, Tomokazu; Takiyoshi, Yuko; Arima, Michiko; Ohama, Rintaro; Yokoyama, Katsuya; Hokazono, Akihiko; Amano, Yumeko; Shimodozono, Megumi; Kawahira, Kazumi

    2016-11-01

    Repetitive facilitative exercise (RFE) is a developed approach to the rehabilitation of hemiplegia. RFE can be integrated with neuromuscular electrical stimulation (NMES), direct application of vibratory stimulation (DAVS) and repetitive transcranial magnetic stimulation (rTMS). The aims of the present study were to retrospectively compare the effects of RFE and NMES, DAVS with those of RFE and rTMS, and to determine the maximal effect of the combination of RFE with NMES, DAVS, rTMS and pharmacological treatments in stroke patients. Thirty-three stroke patients were enrolled and divided into three groups: 15 who received RFE with rTMS (4 min) (TMS4 alone), 9 who received RFE with NMES, DAVS (NMES, DAVS alone) and 9 who received RFE with NMES, DAVS and rTMS (10 min) (rTMS10 + NMES, DAVS). The subjects performed the Fugl-Meyer Assessment (FMA) and Action Research Arm Test (ARAT) before and after the 2-week session. The 18 patients in the NMES, DAVS alone and rTMS10 + NMES, DAVS group underwent the intervention for 4 weeks. There were no significant differences in the increases in the FMA, ARAT scores in the three groups. The FMA or ARAT scores in the NMES, DAVS alone and the rTMS10 + NMES, DAVS group were increased significantly. The FMA and ARAT scores were significantly improved after 4 weeks in the NMES, DAVS alone group. RFE with NMES, DAVS may be more effective than RFE with rTMS for the recovery of upper-limb function. Patients who received RFE with NMES, DAVS and pharmacological treatments showed significant functional recovery.

  18. Virtual reality as a tool for evaluation of repetitive rhythmic movements in the elderly and Parkinson's disease patients.

    Directory of Open Access Journals (Sweden)

    Pablo Arias

    Full Text Available This work presents an immersive Virtual Reality (VR system to evaluate, and potentially treat, the alterations in rhythmic hand movements seen in Parkinson's disease (PD and the elderly (EC, by comparison with healthy young controls (YC. The system integrates the subjects into a VR environment by means of a Head Mounted Display, such that subjects perceive themselves in a virtual world consisting of a table within a room. In this experiment, subjects are presented in 1(st person perspective, so that the avatar reproduces finger tapping movements performed by the subjects. The task, known as the finger tapping test (FT, was performed by all three subject groups, PD, EC and YC. FT was carried out by each subject on two different days (sessions, one week apart. In each FT session all subjects performed FT in the real world (FT(REAL and in the VR (FT(VR; each mode was repeated three times in randomized order. During FT both the tapping frequency and the coefficient of variation of inter-tap interval were registered. FT(VR was a valid test to detect differences in rhythm formation between the three groups. Intra-class correlation coefficients (ICC and mean difference between days for FT(VR (for each group showed reliable results. Finally, the analysis of ICC and mean difference between FT(VR vs FT(REAL, for each variable and group, also showed high reliability. This shows that FT evaluation in VR environments is valid as real world alternative, as VR evaluation did not distort movement execution and detects alteration in rhythm formation. These results support the use of VR as a promising tool to study alterations and the control of movement in different subject groups in unusual environments, such as during fMRI or other imaging studies.

  19. Give me a sign: decoding complex coordinated hand movements using high-field fMRI.

    Science.gov (United States)

    Bleichner, Martin G; Jansma, Johan M; Sellmeijer, Jim; Raemaekers, Mathijs; Ramsey, Nicolas F

    2014-03-01

    Decoding movements from the human cortex has been a topic of great interest for controlling an artificial limb in non-human primates and severely paralyzed people. Here we investigate feasibility of decoding gestures from the sensorimotor cortex in humans, using 7 T fMRI. Twelve healthy volunteers performed four hand gestures from the American Sign Language Alphabet. These gestures were performed in a rapid event related design used to establish the classifier and a slow event-related design, used to test the classifier. Single trial patterns were classified using a pattern-correlation classifier. The four hand gestures could be classified with an average accuracy of 63 % (range 35–95 %), which was significantly above chance (25 %). The hand region was, as expected, the most active region, and the optimal volume for classification was on average about 200 voxels, although this varied considerably across individuals. Importantly, classification accuracy correlated significantly with consistency of gesture execution. The results of our study demonstrate that decoding gestures from the hand region of the sensorimotor cortex using 7 T fMRI can reach very high accuracy, provided that gestures are executed in a consistent manner. Our results further indicate that the neuronal representation of hand gestures is robust and highly reproducible. Given that the most active foci were located in the hand region, and that 7 T fMRI has been shown to agree with electrocorticography, our results suggest that this confined region could serve to decode sign language gestures for intracranial brain–computer interfacing using surface grids.

  20. A common control signal and a ballistic stage can explain the control of coordinated eye-hand movements.

    Science.gov (United States)

    Gopal, Atul; Murthy, Aditya

    2016-06-01

    Voluntary control has been extensively studied in the context of eye and hand movements made in isolation, yet little is known about the nature of control during eye-hand coordination. We probed this with a redirect task. Here subjects had to make reaching/pointing movements accompanied by coordinated eye movements but had to change their plans when the target occasionally changed its position during some trials. Using a race model framework, we found that separate effector-specific mechanisms may be recruited to control eye and hand movements when executed in isolation but when the same effectors are coordinated a unitary mechanism to control coordinated eye-hand movements is employed. Specifically, we found that performance curves were distinct for the eye and hand when these movements were executed in isolation but were comparable when they were executed together. Second, the time to switch motor plans, called the target step reaction time, was different in the eye-alone and hand-alone conditions but was similar in the coordinated condition under assumption of a ballistic stage of ∼40 ms, on average. Interestingly, the existence of this ballistic stage could predict the extent of eye-hand dissociations seen in individual subjects. Finally, when subjects were explicitly instructed to control specifically a single effector (eye or hand), redirecting one effector had a strong effect on the performance of the other effector. Taken together, these results suggest that a common control signal and a ballistic stage are recruited when coordinated eye-hand movement plans require alteration.

  1. Decoupling eye and hand movement control: visual short-term memory influences reach planning more than saccade planning.

    Science.gov (United States)

    Issen, Laurel A; Knill, David C

    2012-01-04

    When reaching for objects, humans make saccades to fixate the object at or near the time the hand begins to move. In order to address whether the CNS relies on a common representation of target positions to plan both saccades and hand movements, we quantified the contributions of visual short-term memory (VSTM) to hand and eye movements executed during the same coordinated actions. Subjects performed a sequential movement task in which they picked up one of two objects on the right side of a virtual display (the "weapon"), moved it to the left side of the display (to a "reloading station") and then moved it back to the right side to hit the other object (the target). On some trials, the target was perturbed by 1° of visual angle while subjects moved the weapon to the reloading station. Although subjects did not notice the change, the original position of the target, encoded in VSTM, influenced the motor plans for both the hand and the eye back to the target. Memory influenced motor plans for distant targets more than for near targets, indicating that sensorimotor planning is sensitive to the reliability of available information; however, memory had a larger influence on hand movements than on eye movements. This suggests that spatial planning for coordinated saccades and hand movements are dissociated at the level of processing at which online visual information is integrated with information in short-term memory.

  2. Development of Motor Speed and Associated Movements from 5 to 18 Years

    Science.gov (United States)

    Gasser, Theo; Rousson, Valentin; Caflisch, Jon; Jenni, Oskar G.

    2010-01-01

    Aim: To study the development of motor speed and associated movements in participants aged 5 to 18 years for age, sex, and laterality. Method: Ten motor tasks of the Zurich Neuromotor Assessment (repetitive and alternating movements of hands and feet, repetitive and sequential finger movements, the pegboard, static and dynamic balance,…

  3. An experimental investigation on the influence of hand orientation on the control of trunk-assisted upper-limb movements

    OpenAIRE

    CHEVALOT, N; WANG, X; DORIOT, N

    2003-01-01

    In order to investigate the computationally ill-posed problems related to the kinematic redundancy in both task and joint space of human movements, the present work aims to extend the work done by Wang (1999) and to study trunk-assisted upper limb reaching movements. In particular, the influence of pushing direction on the control of hand trajectory and upper limb movements was studied. The purpose of the paper is to present the main results of this investigation.

  4. Evaluation of EEG Features in Decoding Individual Finger Movements from One Hand

    Directory of Open Access Journals (Sweden)

    Ran Xiao

    2013-01-01

    Full Text Available With the advancements in modern signal processing techniques, the field of brain-computer interface (BCI is progressing fast towards noninvasiveness. One challenge still impeding these developments is the limited number of features, especially movement-related features, available to generate control signals for noninvasive BCIs. A few recent studies investigated several movement-related features, such as spectral features in electrocorticography (ECoG data obtained through a spectral principal component analysis (PCA and direct use of EEG temporal data, and demonstrated the decoding of individual fingers. The present paper evaluated multiple movement-related features under the same task, that is, discriminating individual fingers from one hand using noninvasive EEG. The present results demonstrate the existence of a broadband feature in EEG to discriminate individual fingers, which has only been identified previously in ECoG. It further shows that multiple spectral features obtained from the spectral PCA yield an average decoding accuracy of 45.2%, which is significantly higher than the guess level (P<0.05 and other features investigated (P<0.05, including EEG spectral power changes in alpha and beta bands and EEG temporal data. The decoding of individual fingers using noninvasive EEG is promising to improve number of features for control, which can facilitate the development of noninvasive BCI applications with rich complexity.

  5. Illusory movements induced by tendon vibration in right- and left-handed people.

    Science.gov (United States)

    Tidoni, Emmanuele; Fusco, Gabriele; Leonardis, Daniele; Frisoli, Antonio; Bergamasco, Massimo; Aglioti, Salvatore Maria

    2015-02-01

    Frequency-specific vibratory stimulation of peripheral tendons induces an illusion of limb movement that may be useful for restoring proprioceptive information in people with sensorimotor disability. This potential application may be limited by inter- and intra-subject variability in the susceptibility to such an illusion, which may depend on a variety of factors. To explore the influence of stimulation parameters and participants' handedness on the movement illusion, we vibrated the right and left tendon of the biceps brachii in a group of right- and left-handed people with five stimulation frequencies (from 40 to 120 Hz in step of 20 Hz). We found that all participants reported the expected illusion of elbow extension, especially after 40 and 60 Hz. Left-handers exhibited less variability in reporting the illusion compared to right-handers across the different stimulation frequencies. Moreover, the stimulation of the non-dominant arm elicited a more vivid illusion with faster onset relative to the stimulation of the dominant arm, an effect that was independent from participants' handedness. Overall, our data show that stimulation frequency, handedness and arm dominance influence the tendon vibration movement illusion. The results are discussed in reference to their relevance in linking motor awareness, improving current devices for motor ability recovery after brain or spinal damage and developing prosthetics and virtual embodiment systems.

  6. Movement and Character. Lecture, London, 1946

    Science.gov (United States)

    Montesorri, Maria

    2013-01-01

    Dr. Montessori's words from the 1946 London Lectures describe principles of intelligence and character, the work of the hand, and movement with a purpose as being integral to self-construction. The perfection of movement is spiritual, says Dr. Montessori. Repetition of practical life exercises are exercises in movement with the dignity of human…

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

    Science.gov (United States)

    Spasojević, Sofija; Ilić, Tihomir V.; Stojković, Ivan; Potkonjak, Veljko; Rodić, Aleksandar; Santos-Victor, José

    2017-01-01

    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

  8. Principal components of hand kinematics and neurophysiological signals in motor cortex during reach to grasp movements.

    Science.gov (United States)

    Mollazadeh, Mohsen; Aggarwal, Vikram; Thakor, Nitish V; Schieber, Marc H

    2014-10-15

    A few kinematic synergies identified by principal component analysis (PCA) account for most of the variance in the coordinated joint rotations of the fingers and wrist used for a wide variety of hand movements. To examine the possibility that motor cortex might control the hand through such synergies, we collected simultaneous kinematic and neurophysiological data from monkeys performing a reach-to-grasp task. We used PCA, jPCA and isomap to extract kinematic synergies from 18 joint angles in the fingers and wrist and analyzed the relationships of both single-unit and multiunit spike recordings, as well as local field potentials (LFPs), to these synergies. For most spike recordings, the maximal absolute cross-correlations of firing rates were somewhat stronger with an individual joint angle than with any principal component (PC), any jPC or any isomap dimension. In decoding analyses, where spikes and LFP power in the 100- to 170-Hz band each provided better decoding than other LFP-based signals, the first PC was decoded as well as the best decoded joint angle. But the remaining PCs and jPCs were predicted with lower accuracy than individual joint angles. Although PCs, jPCs or isomap dimensions might provide a more parsimonious description of kinematics, our findings indicate that the kinematic synergies identified with these techniques are not represented in motor cortex more strongly than the original joint angles. We suggest that the motor cortex might act to sculpt the synergies generated by subcortical centers, superimposing an ability to individuate finger movements and adapt the hand to grasp a wide variety of objects.

  9. EEG Event-Related Desynchronization of patients with stroke during motor imagery of hand movement

    Science.gov (United States)

    Tabernig, Carolina B.; Carrere, Lucía C.; Lopez, Camila A.; Ballario, Carlos

    2016-04-01

    Brain Computer Interfaces (BCI) can be used for therapeutic purposes to improve voluntary motor control that has been affected post stroke. For this purpose, desynchronization of sensorimotor rhythms of the electroencephalographic signal (EEG) can be used. But it is necessary to study what happens in the affected motor cortex of this people. In this article, we analyse EEG recordings of hemiplegic stroke patients to determine if it is possible to detect desynchronization in the affected motor cortex during the imagination of movements of the affected hand. Six patients were included in the study; four evidenced desynchronization in the affected hemisphere, one of them showed no results and the EEG recordings of the last patient presented high noise level. These results suggest that we could use the desynchronization of sensorimotor rhythms of the EEG signal as a BCI paradigm in a rehabilitation programme.

  10. Kinect-based sign language recognition of static and dynamic hand movements

    Science.gov (United States)

    Dalawis, Rando C.; Olayao, Kenneth Deniel R.; Ramos, Evan Geoffrey I.; Samonte, Mary Jane C.

    2017-02-01

    A different approach of sign language recognition of static and dynamic hand movements was developed in this study using normalized correlation algorithm. The goal of this research was to translate fingerspelling sign language into text using MATLAB and Microsoft Kinect. Digital input image captured by Kinect devices are matched from template samples stored in a database. This Human Computer Interaction (HCI) prototype was developed to help people with communication disability to express their thoughts with ease. Frame segmentation and feature extraction was used to give meaning to the captured images. Sequential and random testing was used to test both static and dynamic fingerspelling gestures. The researchers explained some factors they encountered causing some misclassification of signs.

  11. Muscle co-activity tuning in Parkinsonian hand movement: disease-specific changes at behavioral and cerebral level

    Directory of Open Access Journals (Sweden)

    A. M. M. evan der Stouwe

    2015-08-01

    Full Text Available We investigated different degrees of muscle co-activity in simple hand movement at behavioral and cerebral level in healthy subjects and Parkinson’s disease (PD patients. We compared ‘singular’ movements, dominated by the activity of one agonist muscle, to ‘composite’ movements, requiring conjoint activity of multiple muscles, in a center-out (right hand step-tracking task. Behavioral parameters were obtained by EMG and kinematic recordings. FMRI was used to investigate differences in underlying brain activ¬¬ations between PD patients (N= 12 and healthy (age-matched subjects (N= 18. In healthy subjects, composite movements recruited the striatum and cortical areas comprising bilaterally the supplementary motor area and premotor cortex, contralateral medial prefrontal cortex, primary motor cortex, primary visual cortex, and ipsilateral superior parietal cortex. Contrarily, the ipsilateral cerebellum was more involved in singular movements. This striking dichotomy between striatal and cortical recruitment versus cerebellar involvement may reflect the complementary roles of these areas in motor control, in which the basal ganglia are involved in movement selection and the cerebellum in movement optimization. Compared to healthy subjects, PD patients showed decreased activation of the striatum and cortical areas in composite movement, while performing worse at behavioral level. This implies that PD patients are especially impaired on tasks requiring highly tuned muscle co-activity. Singular movement, on the other hand, was characterized by a combination of increased activation of the ipsilateral parietal cortex and left cerebellum. As singular movement performance was only slightly compromised, we interpret this as a reflection of increased visuospatial processing, possibly as a compensational mechanism.

  12. Are movements necessary for the sense of body ownership? Evidence from the rubber hand illusion in pure hemiplegic patients.

    Directory of Open Access Journals (Sweden)

    Dalila Burin

    Full Text Available A question still debated within cognitive neuroscience is whether signals present during actions significantly contribute to the emergence of human's body ownership. In the present study, we aimed at answer this question by means of a neuropsychological approach. We administered the classical rubber hand illusion paradigm to a group of healthy participants and to a group of neurological patients affected by a complete left upper limb hemiplegia, but without any propriceptive/tactile deficits. The illusion strength was measured both subjectively (i.e., by a self-report questionnaire and behaviorally (i.e., the location of one's own hand is shifted towards the rubber hand. We aimed at examining whether, and to which extent, an enduring absence of movements related signals affects body ownership. Our results showed that patients displayed, respect to healthy participants, stronger illusory effects when the left (affected hand was stimulated and no effects when the right (unaffected hand was stimulated. In other words, hemiplegics had a weaker/more flexible sense of body ownership for the affected hand, but an enhanced/more rigid one for the healthy hand. Possible interpretations of such asymmetrical distribution of body ownership, as well as limits of our results, are discussed. Broadly speaking, our findings suggest that the alteration of the normal flow of signals present during movements impacts on human's body ownership. This in turn, means that movements have a role per se in developing and maintaining a coherent body ownership.

  13. Are movements necessary for the sense of body ownership? Evidence from the rubber hand illusion in pure hemiplegic patients.

    Science.gov (United States)

    Burin, Dalila; Livelli, Alessandro; Garbarini, Francesca; Fossataro, Carlotta; Folegatti, Alessia; Gindri, Patrizia; Pia, Lorenzo

    2015-01-01

    A question still debated within cognitive neuroscience is whether signals present during actions significantly contribute to the emergence of human's body ownership. In the present study, we aimed at answer this question by means of a neuropsychological approach. We administered the classical rubber hand illusion paradigm to a group of healthy participants and to a group of neurological patients affected by a complete left upper limb hemiplegia, but without any propriceptive/tactile deficits. The illusion strength was measured both subjectively (i.e., by a self-report questionnaire) and behaviorally (i.e., the location of one's own hand is shifted towards the rubber hand). We aimed at examining whether, and to which extent, an enduring absence of movements related signals affects body ownership. Our results showed that patients displayed, respect to healthy participants, stronger illusory effects when the left (affected) hand was stimulated and no effects when the right (unaffected) hand was stimulated. In other words, hemiplegics had a weaker/more flexible sense of body ownership for the affected hand, but an enhanced/more rigid one for the healthy hand. Possible interpretations of such asymmetrical distribution of body ownership, as well as limits of our results, are discussed. Broadly speaking, our findings suggest that the alteration of the normal flow of signals present during movements impacts on human's body ownership. This in turn, means that movements have a role per se in developing and maintaining a coherent body ownership.

  14. Repetitive transcranial magnetic stimulation attenuates the perception of force output production in non-exercised hand muscles after unilateral exercise.

    Science.gov (United States)

    Goodall, Stuart; St Clair Gibson, Alan; Voller, Bernhard; Lomarev, Mike; Howatson, Glyn; Dang, Nguyet; Hortobágyi, Tibor; Hallett, Mark

    2013-01-01

    We examined whether unilateral exercise creates perception bias in the non-exercised limb and ascertained whether rTMS applied to the primary motor cortex (M1) interferes with this perception. All participants completed 4 interventions: 1) 15-min learning period of intermittent isometric contractions at 35% MVC with the trained hand (EX), 2) 15-min learning period of intermittent isometric contractions at 35% MVC with the trained hand whilst receiving rTMS over the contralateral M1 (rTMS+EX); 3) 15-min of rTMS over the 'trained' M1 (rTMS) and 4) 15-min rest (Rest). Pre and post-interventions, the error of force output production, the perception of effort (RPE), motor evoked potentials (MEPs) and compound muscle action potentials (CMAPs) were measured in both hands. EX did not alter the error of force output production in the trained hand (Δ3%; P>0.05); however, the error of force output production was reduced in the untrained hand (Δ12%; Phand. EX increased RPE in the trained hand (9.1±0.5 vs. 11.3±0.7; Phand (8.8±0.6 vs. 9.2±0.6; P>0.05). RPE was significantly higher after rTMS+EX in the trained hand (9.2±0.5 vs. 10.7±0.7; Phand (8.5±0.6 vs. 9.2±0.5; P>0.05). The novel finding was that exercise alone reduced the error in force output production by over a third in the untrained hand. Further, when exercise was combined with rTMS the transfer of force perception was attenuated. These data suggest that the contralateral M1 of the trained hand might, in part, play an essential role for the transfer of force perception to the untrained hand.

  15. Effect of single-session repetitive transcranial magnetic stimulation applied over the hand versus leg motor area on pain after spinal cord injury.

    Science.gov (United States)

    Jetté, Fanny; Côté, Isabelle; Meziane, Hadj Boumediene; Mercier, Catherine

    2013-09-01

    Neuropathic pain often follows spinal cord injury (SCI). To compare the effect of repetitive transcranial magnetic stimulation (rTMS) applied over different motor cortex targets (hand vs leg area) versus sham stimulation on neuropathic pain and local neurophysiological changes in patients with SCI. A total of 16 patients with complete or incomplete motor SCI and chronic neuropathic pain participated in a double-blind, cross-over randomized study. Three single sessions of sham or active rTMS (10 Hz, total of 2000 stimuli) were applied in random order over the hand or leg area with a minimal 2-week interval. THE MAIN OUTCOME MEASURES: were the numeric rating scale for pain sensation and parameters derived from motor mapping of the first dorsal interosseous muscle, including maximal amplitude of evoked response as well as map area, volume, and location. rTMS applied to either the hand or the leg area, but not sham stimulation, induced a significant but equivalent reduction in pain for the first 48 hours postintervention (P stimulation of the hand area (P = .04) but not for the other conditions. rTMS applied over the hand or leg motor cortex decreased neuropathic pain regardless of any change in cortical excitability, suggesting that the analgesic effect is not associated with local changes at the motor cortex level itself.

  16. [Obsessive-compulsive symptoms, tics, stereotypic movements or need for absolute consistency? The occurrence of repetitive activities in patients with pervasive developmental disorders--case studies].

    Science.gov (United States)

    Bryńska, Anita; Lipińska, Elzbieta; Matelska, Monika

    2011-01-01

    Repetitive and stereotyped behaviours in the form of stereotyped interests or specific routine activities are one ofthe diagnostic criteria in pervasive developmental disorders. The occurrence of repetitive behaviours in patients with pervasive developmental disorders is a starting point for questions about the type and classification criteria of such behaviours. The aim of the article is to present case studies of patients with pervasive developmental disorders and co-morbid symptoms in the form of routine activities, tics, obsessive-compulsive symptoms or stereotyped behaviours. The first case study describes a patient with Asperger's syndrome and obsessive compulsive symptoms. The diagnostic problems regarding complex motor tics are discussed in the second case study which describes a patient with Asperger's syndrome and Gilles de la Tourette syndrome. The third and fourth case study describes mono-zygotic twins with so called High Functioning Autism whose repetitive activities point to either obsessive compulsive symptoms, stereotypic movements, need for absolute consistency or echopraxia. The possible comorbidity of pervasive developmental disorders and symptoms in the form of repetitive behaviours, possible interactions as well as diagnostic challenges is discussed in the article.

  17. Comparison of Brunnstrom movement therapy and Motor Relearning Program in rehabilitation of post-stroke hemiparetic hand: a randomized trial.

    Science.gov (United States)

    Pandian, Shanta; Arya, Kamal Narayan; Davidson, E W Rajkumar

    2012-07-01

    Motor recovery of the hand usually plateaus in chronic stroke patients. Various conventional and contemporary approaches have been used to rehabilitate the hand post-stroke. However, the evidence for their effectiveness is still limited. To compare the hand therapy protocols based on Brunnstrom approach and motor relearning program in rehabilitation of the hand of chronic stroke patients. Randomized trial. Outpatients attending the occupational therapy department of a rehabilitation institute. 30 post-stroke subjects (35.06 ± 14.52 months) were randomly assigned into two equal groups (Group A and Group B), Outcome Measures: Brunnstrom recovery stages of hand (BRS-H), Fugl-Meyer assessment: wrist and hand (FMA-WH). Group A received Brunnstrom hand manipulation (BHM). BHM is the hand treatment protocol of the Brunnstrom movement therapy, which uses synergies and reflexes to develop voluntary motor control. Group B received the Motor Relearning Program (MRP) based hand protocol. MRP is the practice of specific motor skills, which results in the ability to perform a task. Active practice of context-specific motor task such as reaching and grasping helps regain the lost motor functions. Both the therapy protocols were effective in rehabilitation of the hand (BRS-H; p = 0.003 to 0.004, FMA-WH; p rehabilitation of the hand in chronic post-stroke patients. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Mirror activity in the human brain while observing hand movements: a comparison between EEG desynchronization in the mu-range and previous fMRI results.

    Science.gov (United States)

    Perry, Anat; Bentin, Shlomo

    2009-07-28

    Mu (mu) rhythms are EEG oscillations between 8-13 Hz distinguished from alpha by having more anterior distribution and being desynchronized by motor rather than visual activity. Evidence accumulating during the last decade suggests that the desynchronization of mu rhythms (mu suppression) might be also a manifestation of a human Mirror Neuron System (MNS). To further explore this hypothesis we used a paradigm that, in a previous fMRI study, successfully activated this putative MNS in humans. Our direct goal was to provide further support for a link between modulation of mu rhythms and the MNS, by finding parallels between the reported patterns of fMRI activations and patterns of mu suppression. The EEG power in the mu range has been recorded while participants passively observed either a left or a right hand, reaching to and grasping objects, and compared it with that recorded while participants observed the movement of a ball, and while observing static grasping scenes or still objects. Mirroring fMRI results (Shmuelof, L., Zohary, E., 2005. Dissociation between ventral and dorsal fMRI activation during object and action recognition. Neuron 47, 457-470), mu suppression was larger in the hemisphere contra-lateral to the moving hand and larger when the hands grasped different objects in different ways than when the movement was repetitive. No suppression was found while participants observed still objects but mu suppression was also found while seeing static grasping postures. These data are discussed in light of similar parallels between modulations of alpha waves and fMRI while recording EEG in the magnet. The present data support a link between mu suppression and a human MNS.

  19. Processing of hand-related verbs specifically affects the planning and execution of arm reaching movements.

    Directory of Open Access Journals (Sweden)

    Giovanni Mirabella

    Full Text Available Even though a growing body of research has shown that the processing of action language affects the planning and execution of motor acts, several aspects of this interaction are still hotly debated. The directionality (i.e. does understanding action-related language induce a facilitation or an interference with the corresponding action?, the time course, and the nature of the interaction (i.e. under what conditions does the phenomenon occur? are largely unclear. To further explore this topic we exploited a go/no-go paradigm in which healthy participants were required to perform arm reaching movements toward a target when verbs expressing either hand or foot actions were shown, and to refrain from moving when abstract verbs were presented. We found that reaction times (RT and percentages of errors increased when the verb involved the same effector used to give the response. This interference occurred very early, when the interval between verb presentation and the delivery of the go signal was 50 ms, and could be elicited until this delay was about 600 ms. In addition, RTs were faster when subjects used the right arm than when they used the left arm, suggesting that action-verb understanding is left-lateralized. Furthermore, when the color of the printed verb and not its meaning was the cue for movement execution the differences between RTs and error percentages between verb categories disappeared, unequivocally indicating that the phenomenon occurs only when the semantic content of a verb has to be retrieved. These results are compatible with the theory of embodied language, which hypothesizes that comprehending verbal descriptions of actions relies on an internal simulation of the sensory-motor experience of the action, and provide a new and detailed view of the interplay between action language and motor acts.

  20. Transcranial alternating current stimulation to the inferior parietal lobe decreases mu suppression to egocentric, but not allocentric hand movements.

    Science.gov (United States)

    Berntsen, Monica B; Cooper, Nicholas R; Romei, Vincenzo

    2017-03-06

    Egocentric vs. allocentric perspective during observation of hand movements has been related to self-other differentiation such that movements observed from an egocentric viewpoint have been considered as self-related while movements observed from an allocentric viewpoint have been considered as belonging to someone else. Correlational studies have generally found that egocentric perspective induces greater neurophysiological responses and larger behavioral effects compared to an allocentric perspective. However, recent studies question previous findings by reporting greater (μ) suppression and greater transcranial magnetic stimulation (TMS)-induced motor-evoked potentials (MEPs) during observation of allocentric compared to egocentric movements. Furthermore, self-other differentiation has been generally related to activity within the inferior parietal lobe (IPL), but direct evidence for a causal and functional role of IPL in self-other differentiation is lacking. The current study was therefore designed to investigate the influence that IPL exerts on self-other differentiation. To this aim, we measured the impact of individually adjusted alpha-tuned transcranial alternating current stimulation (tACS) applied over IPL on μ-suppression during hands movement observation from an egocentric and allocentric perspective. Electroencephalography (EEG) was recorded during movement observation before and immediately after tACS. Results demonstrated that tACS decreased μ-reactivity over sensorimotor (but not visual) regions for egocentric (but not allocentric) movement observation providing direct evidence for a causal involvement of IPL in the observation of self- but not other-related hand movement. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Aberrant Oscillatory Activity during Simple Movement in Task-Specific Focal Hand Dystonia.

    Science.gov (United States)

    Hinkley, Leighton B N; Dolberg, Rebecca; Honma, Susanne; Findlay, Anne; Byl, Nancy N; Nagarajan, Srikantan S

    2012-01-01

    In task-specific focal hand dystonia (tspFHD), the temporal dynamics of cortical activity in the motor system and how these processes are related to impairments in sensory and motor function are poorly understood. Here, we use time-frequency reconstructions of magnetoencephalographic (MEG) data to elaborate the temporal and spatial characteristics of cortical activity during movement. A self-paced finger tapping task during MEG recording was performed by 11 patients with tspFHD and 11 matched healthy controls. In both groups robust changes in beta (12-30 Hz) and high gamma (65-90 Hz) oscillatory activity were identified over sensory and motor cortices during button press. A significant decrease [p press. Furthermore, an increase (p press in patients with tspFHD. Oscillatory activity within in the tspFHD group was however not correlated with clinical measures. Understanding these aberrant oscillatory dynamics can provide the groundwork for interventions that focus on modulating the timing of this activity.

  2. Regional cerebral blood flow during rest and skilled hand movements by xenon-133 inhalation and emission computerized tomography

    DEFF Research Database (Denmark)

    Lauritzen, M; Henriksen, L; Lassen, N A

    1981-01-01

    Regional cerebral blood flow (CBF) was studied in 16 normal adult volunteers during rest and in 10 the study was repeated during skilled hand movements. A fast-rotating ("dynamic"), single-photon emission computerized tomograph (ECT) with four detector heads was used. Xenon-133 was inhaled over a 1...

  3. Neural substrates of visual spatial coding and visual feedback control for hand movements in allocentric and target-directed tasks

    Directory of Open Access Journals (Sweden)

    Lore eThaler

    2011-08-01

    Full Text Available Neuropsychological evidence suggests that different brain areas may be involved in movements that are directed at visual targets (e.g. pointing or reaching, and movements that are based on allocentric visual information (e.g. drawing or copying. Here we used fMRI to investigate the neural correlates of these two types of movements in healthy volunteers. Subjects (n=14 performed right-hand movements in either a target-directed task (moving a cursor to a target dot or an allocentric task (moving a cursor to reproduce the distance and direction between two distal target dots with or without visual feedback about their hand movement. Movements were monitored with an MR compatible touch panel. A whole-brain analysis revealed that movements in allocentric conditions led to an increase in activity in the fundus of the left intraparietal sulcus (IPS, in posterior IPS, in bilateral dorsal premotor cortex (PMd, and in the Lateral Occipital Complex (LOC. Visual feedback in both target-directed and allocentric conditions led to an increase in activity in area MT+, superior parietal occipital cortex (SPOC and posterior IPS (all bilateral. In addition, we found that visual feedback affected brain activity differently in target-directed as compared to allocentric conditions, in particular in pre-supplementary motor area, PMd, IPS and parieto-occipital cortex. Our results, in combination with previous findings, suggest that the LOC is essential for allocentric visual coding and that SPOC is involved in visual feedback control. The differences in brain activity between target-directed and allocentric visual feedback conditions may be related to behavioral differences in visual feedback control. Our results advance the understanding of the visual coordinate frame used by the LOC. In addition, because of the nature of the allocentric task, our results have relevance for the understanding of neural substrates of magnitude estimation and vector-coding of movements.

  4. 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

    2017-09-11

    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.

  5. 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.

  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. Are there right hemisphere contributions to visually-guided movement? Manipulating left hand reaction time advantages in dextrals

    Directory of Open Access Journals (Sweden)

    David Peter Carey

    2015-08-01

    Full Text Available Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right –hemisphere damage, to those using neurologically-intact participants, by assuming that each hand has privileged access to the contralateral hemisphere. Previous attempts to illustrate right hemispheric contributions to the control of aiming have focussed on increasing the spatial demands of an aiming task, to attenuate the typical right hand advantages, to try to enhance a left hand reaction time advantage in right-handed participants. These early attempts have not been successful. The present study circumnavigates some of the theoretical and methodological difficulties of some of the earlier experiments, by using three different tasks linked to specialised functions of the right hemisphere: bisecting, the gap effect, and visuospatial localisation. None of these tasks were effective in reducing the magnitude of left hand reaction time advantages in right handers. Results are discussed in terms of alternatives to right hemispheric functional explanations of the effect, the one dimensional nature of our target arrays, power and precision given the size of the left hand RT effect, and the utility of examining the proportions of participants who show these effects, rather than exclusive reliance on measures of central tendency and their associated null hypothesis significance tests.

  8. Are there right hemisphere contributions to visually-guided movement? Manipulating left hand reaction time advantages in dextrals.

    Science.gov (United States)

    Carey, David P; Otto-de Haart, E Grace; Buckingham, Gavin; Dijkerman, H Chris; Hargreaves, Eric L; Goodale, Melvyn A

    2015-01-01

    Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right-hemisphere damage, to those using neurologically-intact participants, by assuming that each hand has privileged access to the contralateral hemisphere. Previous attempts to illustrate right hemispheric contributions to the control of aiming have focussed on increasing the spatial demands of an aiming task, to attenuate the typical right hand advantages, to try to enhance a left hand reaction time advantage in right-handed participants. These early attempts have not been successful. The present study circumnavigates some of the theoretical and methodological difficulties of some of the earlier experiments, by using three different tasks linked directly to specialized functions of the right hemisphere: bisecting, the gap effect, and visuospatial localization. None of these tasks were effective in reducing the magnitude of left hand reaction time advantages in right handers. Results are discussed in terms of alternatives to right hemispheric functional explanations of the effect, the one-dimensional nature of our target arrays, power and precision given the size of the left hand RT effect, and the utility of examining the proportions of participants who show these effects, rather than exclusive reliance on measures of central tendency and their associated null hypothesis significance tests.

  9. Brain activation related to combinations of gaze position, visual input, and goal-directed hand movements.

    Science.gov (United States)

    Bédard, Patrick; Wu, Min; Sanes, Jerome N

    2011-06-01

    Humans reach to and acquire objects by transforming visual targets into action commands. How the brain integrates goals specified in a visual framework to signals into a suitable framework for an action plan requires clarification whether visual input, per se, interacts with gaze position to formulate action plans. To further evaluate brain control of visual-motor integration, we assessed brain activation, using functional magnetic resonance imaging. Humans performed goal-directed movements toward visible or remembered targets while fixating gaze left or right from center. We dissociated movement planning from performance using a delayed-response task and manipulated target visibility by its availability throughout the delay or blanking it 500 ms after onset. We found strong effects of gaze orientation on brain activation during planning and interactive effects of target visibility and gaze orientation on movement-related activation during performance in parietal and premotor cortices (PM), cerebellum, and basal ganglia, with more activation for rightward gaze at a visible target and no gaze modulation for movements directed toward remembered targets. These results demonstrate effects of gaze position on PM and movement-related processes and provide new information how visual signals interact with gaze position in transforming visual inputs into motor goals.

  10. Split-brain monkeys : cerebral control of contralateral and ipsilateral arm, hand and finger movements

    NARCIS (Netherlands)

    J. Brinkman (Jacoba)

    1974-01-01

    textabstractIn the present study, an investigation has been made of the visuomotor control exerted by one half of the brain over each of the two upper extremities in the rhesus monkey. The hypothesis that one half of the brain can steer movements of each of the two extremities relatively independent

  11. Hands-free Head-movement Gesture Recognition using Artificial Neural Networks and the Magnified Gradient Function.

    Science.gov (United States)

    King, L M; Nguyen, H T; Taylor, P B

    2005-01-01

    This paper presents a hands-free head-movement gesture classification system using a Neural Network employing the Magnified Gradient Function (MGF) algorithm. The MGF increases the rate of convergence by magnifying the first order derivative of the activation function, whilst guaranteeing convergence. The MGF is tested on able-bodied and disabled users to measure its accuracy and performance. It is shown that for able-bodied users, a classification improvement from 98.25% to 99.85% is made, and 92.08% to 97.50% for disabled users.

  12. 一种新型穿戴式手功能康复机器人%A Novel Wearable Robot of Hand Repetitive Therapy

    Institute of Scientific and Technical Information of China (English)

    邢科新; 徐琦; 黄剑; 王永骥; 吴军

    2009-01-01

    针对中风和脑外伤患者的运动功能障碍问题,设计了一种新型的穿戴式手功能康复机器人.机器人采用气动肌肉驱动,能够辅助患者完成手指多关节复合运动功能训练.该机器人有3个自由度,通过角度和力传感器获取患手一机器人组合系统的状态参数,并采用虚拟现实技术构建康复治疗虚拟环境,提高患者的训练兴趣,从而增强康复效果.采用传统的PID控制器进行了临床实验,实现了关节角度的三次样条参考轨迹跟踪,实验结果验证了所设计的穿戴式手功能康复机器人的可用性和有效性.%A novel wearable robot of hand repetitive therapy was developed for stroke and traumatic brain rehabilitation. The robot driven by peneumatic muscles can help patients to complete repetitive training task for motion function rehabilitation of their fingers' joints. The robot had three degrees of freedom, which was equipped with three angle sensors and two force sensors to acquire the state of the human-robot hybrid system. At the same time, virtual reality technology was used to build a virtual rehabilitation environment in the system in order to enhance the patient's interest and optimize the effect of rehabilitation. Finally, a conventional PID controller was implemented and the cubic spline function trajectory tracking control for joint's angles was realized. Experiments were performed to confirm the effectiveness of the proposed devic and methods.

  13. The PowerGlove: assessment of hand and finger movements in Parkinson’s disease patients

    NARCIS (Netherlands)

    Dijk, van K.J.; Verhagen, R.; Noort, van den J.; Bour, L.J.; Veltink, P.H.; Heida, T.

    2015-01-01

    Objective: The aim of the study is to test whether the PowerGlove (PG), an instrumented glove which consists of inertial (accelerometers and gyroscopes) and magnetic sensors, is a valid and reliable instrument to measure different degrees of hand motor impairments in patients with Parkinson’s diseas

  14. Similar hand shaping in reaching-for-food (skilled reaching) in rats and humans provides evidence of homology in release, collection, and manipulation movements.

    Science.gov (United States)

    Sacrey, Lori-Ann R; Alaverdashvili, Mariam; Whishaw, Ian Q

    2009-12-01

    Many animal species use their forelimbs to assist in eating, such as occurs in a reach-to-eat task (skilled reaching) in which a forelimb is extended to grasp food that is placed in the mouth for eating. It is unclear the extent to which the skilled reaching movements of different species share common ancestry and so are homologous or evolved independently and so are analogous (homoplasy). Here hand shaping (the movements of the hand and digits) that occur as the hand is transported to the target, were examined using high-speed (1000 frames/s) video recording and kinematic measurement (Peak Motus) in the rat (Rattus norvegicus) and human (Homo sapiens). Ten movement similarities were identified from the point that the limb initiated transport towards the food item to the point that the food was grasped. The digits were closed and semi-flexed as the hand was lifted (released from a substrate) and supinated. They closed further as the hand was collected for aiming. They then extended as the hand was transported to the target and then opened in conjunction with pronation to orient the hand for grasping (manipulation). Finally the digits were flexed and closed for grasping. These movements occurred at approximately the same point of limb transport in both species even though the rat used a whole paw grasp and the humans used a pincer grasp. Bushbabies (Galago garnettii), titi monkeys (Callicebus brunneus), rhesus monkeys (Macaca mulatta) and the bonobo (Pan paniscus) displayed similar hand shaping in skilled reaching despite species differences in grasping movements. Homologous hand shaping in the rodent clade and the primate clade and within the primate lineage is discussed in relation to its possible derivation from hand shaping movements associated with stepping.

  15. [The effect of the membrana interossea antebrachii on the turning movement of the hand].

    Science.gov (United States)

    Küsswetter, W

    1979-09-20

    In human cadaveric forearm specimens the membrana interossea antebrachii was examined morphologically and biomechanically. Macroscopical, submacroscopical and microscopical findings reveal new facts about the structure, texture and the microscopical details of the membrana interossea. By measuring the interosseous space and by straingage measurement of elongation of the interosseous membrane during pronation and supination the influence of the membrana interossea antebrachii on pronation and supination of the hand was analyzed biomechanically.

  16. Hand-movement-based in-vehicle driver/front-seat passenger discrimination for centre console controls

    Science.gov (United States)

    Herrmann, Enrico; Makrushin, Andrey; Dittmann, Jana; Vielhauer, Claus; Langnickel, Mirko; Kraetzer, Christian

    2010-01-01

    Successful user discrimination in a vehicle environment may yield a reduction of the number of switches, thus significantly reducing costs while increasing user convenience. The personalization of individual controls permits conditional passenger enable/driver disable and vice versa options which may yield safety improvement. The authors propose a prototypic optical sensing system based on hand movement segmentation in near-infrared image sequences implemented in an Audi A6 Avant. Analyzing the number of movements in special regions, the system recognizes the direction of the forearm and hand motion and decides whether driver or front-seat passenger touch a control. The experimental evaluation is performed independently for uniformly and non-uniformly illuminated video data as well as for the complete video data set which includes both subsets. The general test results in error rates of up to 14.41% FPR / 16.82% FNR and 17.61% FPR / 14.77% FNR for driver and passenger respectively. Finally, the authors discuss the causes of the most frequently occurring errors as well as the prospects and limitations of optical sensing for user discrimination in passenger compartments.

  17. Movement-related activity during goal-directed hand actions in the monkey ventrolateral prefrontal cortex.

    Science.gov (United States)

    Simone, Luciano; Rozzi, Stefano; Bimbi, Marco; Fogassi, Leonardo

    2015-12-01

    Grasping actions require the integration of two neural processes, one enabling the transformation of object properties into corresponding motor acts, and the other involved in planning and controlling action execution on the basis of contextual information. The first process relies on parieto-premotor circuits, whereas the second is considered to be a prefrontal function. Up to now, the prefrontal cortex has been mainly investigated with conditional visuomotor tasks requiring a learned association between cues and behavioural output. To clarify the functional role of the prefrontal cortex in grasping actions, we recorded the activity of ventrolateral prefrontal (VLPF) neurons while monkeys (Macaca mulatta) performed tasks requiring reaching-grasping actions in different contextual conditions (in light and darkness, memory-guided, and in the absence of abstract learned rules). The results showed that the VLPF cortex contains neurons that are active during action execution (movement-related neurons). Some of them showed grip selectivity, and some also responded to object presentation. Most movement-related neurons discharged during action execution both with and without visual feedback, and this discharge typically did not change when the action was performed with object mnemonic information and in the absence of abstract rules. The findings of this study indicate that a population of VLPF neurons play a role in controlling goal-directed grasping actions in several contexts. This control is probably exerted within a wider network, involving parietal and premotor regions, where the role of VLPF movement-related neurons would be that of activating, on the basis of contextual information, the representation of the motor goal of the intended action (taking possession of an object) during action planning and execution.

  18. Effect of Observation of Simple Hand Movement on Brain Activations in Patients with Unilateral Cerebral Palsy: An fMRI Study

    Science.gov (United States)

    Dinomais, Mickael; Lignon, Gregoire; Chinier, Eva; Richard, Isabelle; Minassian, Aram Ter; The Tich, Sylvie N'Guyen

    2013-01-01

    The aim of this functional magnetic resonance imaging (fMRI) study was to examine and compare brain activation in patients with unilateral cerebral palsy (CP) during observation of simple hand movement performed by the paretic and nonparetic hand. Nineteen patients with clinical unilateral CP (14 male, mean age 14 years, 7-21 years) participated…

  19. Smart Sensor-Based Motion Detection System for Hand Movement Training in Open Surgery.

    Science.gov (United States)

    Sun, Xinyao; Byrns, Simon; Cheng, Irene; Zheng, Bin; Basu, Anup

    2017-02-01

    We introduce a smart sensor-based motion detection technique for objective measurement and assessment of surgical dexterity among users at different experience levels. The goal is to allow trainees to evaluate their performance based on a reference model shared through communication technology, e.g., the Internet, without the physical presence of an evaluating surgeon. While in the current implementation we used a Leap Motion Controller to obtain motion data for analysis, our technique can be applied to motion data captured by other smart sensors, e.g., OptiTrack. To differentiate motions captured from different participants, measurement and assessment in our approach are achieved using two strategies: (1) low level descriptive statistical analysis, and (2) Hidden Markov Model (HMM) classification. Based on our surgical knot tying task experiment, we can conclude that finger motions generated from users with different surgical dexterity, e.g., expert and novice performers, display differences in path length, number of movements and task completion time. In order to validate the discriminatory ability of HMM for classifying different movement patterns, a non-surgical task was included in our analysis. Experimental results demonstrate that our approach had 100 % accuracy in discriminating between expert and novice performances. Our proposed motion analysis technique applied to open surgical procedures is a promising step towards the development of objective computer-assisted assessment and training systems.

  20. Deep Learning with Convolutional Neural Networks Applied to Electromyography Data: A Resource for the Classification of Movements for Prosthetic Hands

    Science.gov (United States)

    Atzori, Manfredo; Cognolato, Matteo; Müller, Henning

    2016-01-01

    Natural control methods based on surface electromyography (sEMG) and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications, and commercial prostheses are capable of offering natural control for only a few movements. In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its methods for natural control of robotic hands via sEMG using a large number of intact subjects and amputees. We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 transradial amputees. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets. The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods, but lower than the results obtained with the best reference methods in our tests. The results show that convolutional neural networks with a very simple architecture can produce accurate results comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters) can be fundamental for the analysis of sEMG data. Larger networks can achieve higher accuracy on computer vision and object recognition tasks. This fact suggests that it may be interesting to evaluate if larger networks can increase sEMG classification accuracy too. PMID:27656140

  1. Deep Learning with Convolutional Neural Networks Applied to Electromyography Data: A Resource for the Classification of Movements for Prosthetic Hands.

    Science.gov (United States)

    Atzori, Manfredo; Cognolato, Matteo; Müller, Henning

    2016-01-01

    Natural control methods based on surface electromyography (sEMG) and pattern recognition are promising for hand prosthetics. However, the control robustness offered by scientific research is still not sufficient for many real life applications, and commercial prostheses are capable of offering natural control for only a few movements. In recent years deep learning revolutionized several fields of machine learning, including computer vision and speech recognition. Our objective is to test its methods for natural control of robotic hands via sEMG using a large number of intact subjects and amputees. We tested convolutional networks for the classification of an average of 50 hand movements in 67 intact subjects and 11 transradial amputees. The simple architecture of the neural network allowed to make several tests in order to evaluate the effect of pre-processing, layer architecture, data augmentation and optimization. The classification results are compared with a set of classical classification methods applied on the same datasets. The classification accuracy obtained with convolutional neural networks using the proposed architecture is higher than the average results obtained with the classical classification methods, but lower than the results obtained with the best reference methods in our tests. The results show that convolutional neural networks with a very simple architecture can produce accurate results comparable to the average classical classification methods. They show that several factors (including pre-processing, the architecture of the net and the optimization parameters) can be fundamental for the analysis of sEMG data. Larger networks can achieve higher accuracy on computer vision and object recognition tasks. This fact suggests that it may be interesting to evaluate if larger networks can increase sEMG classification accuracy too.

  2. S-R compatibility effects on motor potentials associated with hand and foot movements.

    Science.gov (United States)

    Miller, Jeff

    2016-04-01

    Two four-choice reaction time (RT) experiments used the lateralized readiness potential (LRP) and the limb selection potential (LSP) to assess the effects of spatial S-R compatibility on motor processes. Individual stimuli were presented at one corner of a square centered at fixation, and each response was made with the left or right hand or foot. In Experiment 1, the correct response was determined by stimulus location, whereas in Experiment 2 it was determined by stimulus identity. Horizontal and vertical compatibility affected both RT and response accuracy, but the LRP and LSP results suggested that compatibility had little or no direct effect on the duration of motor processes. In addition, the results suggest that the relatively new LSP measure is a useful index of motor activation processes. Its insensitivity to horizontal stimulus artifacts makes it especially useful for studying the effects of horizontal spatial compatibility.

  3. Evolution and homologies of primate and modern human hand and forearm muscles, with notes on thumb movements and tool use.

    Science.gov (United States)

    Diogo, Rui; Richmond, Brian G; Wood, Bernard

    2012-07-01

    In this paper, we explore how the results of a primate-wide higher-level phylogenetic analysis of muscle characters can improve our understanding of the evolution and homologies of the forearm and hand muscles of modern humans. Contrary to what is often suggested in the literature, none of the forearm and hand muscle structures usually present in modern humans are autapomorphic. All are found in one or more extant non-human primate taxa. What is unique is the particular combination of muscles. However, more muscles go to the thumb in modern humans than in almost all other primates, reinforcing the hypothesis that focal thumb movements probably played an important role in human evolution. What makes the modern human thumb myology special within the primate clade is not so much its intrinsic musculature but two extrinsic muscles, extensor pollicis brevis and flexor pollicis longus, that are otherwise only found in hylobatids. It is likely that these two forearm muscles play different functional roles in hylobatids and modern humans. In the former, the thumb is separated from elongated digits by a deep cleft and there is no pulp-to-pulp opposition, whereas modern humans exhibit powerful thumb flexion and greater manipulative abilities, such as those involved in the manufacture and use of tools. The functional and evolutionary significance of a third peculiar structure, the intrinsic hand structure that is often called the 'interosseous volaris primus of Henle' (and which we suggest is referred to as the musculus adductor pollicis accessorius) is still obscure. The presence of distinct contrahentes digitorum and intermetacarpales in adult chimpanzees is likely the result of prolonged or delayed development of the hand musculature of these apes. In relation to these structures, extant chimpanzees are more neotenic than modern humans. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. The Analysis of Hand Movement Distinction Based on Relative Frequency Band Energy Method

    Directory of Open Access Journals (Sweden)

    Yanyan Zhang

    2014-01-01

    Full Text Available For the purpose of successfully developing a prosthetic control system, many attempts have been made to improve the classification accuracy of surface electromyographic (SEMG signals. Nevertheless, the effective feature extraction is still a paramount challenge for the classification of SEMG signals. The relative frequency band energy (RFBE method based on wavelet packet decomposition was proposed for the prosthetic pattern recognition of multichannel SEMG signals. Firstly, the wavelet packet energy of SEMG signals in each subspace was calculated by using wavelet packet decomposition and the RFBE of each frequency band was obtained by the wavelet packet energy. Then, the principal component analysis (PCA and the Davies-Bouldin (DB index were used to perform the feature selection. Lastly, the support vector machine (SVM was applied for the classification of SEMG signals. Our results demonstrated that the RFBE approach was suitable for identifying different types of forearm movements. By comparing with other classification methods, the proposed method achieved higher classification accuracy in terms of the classification of SEMG signals.

  5. Automated Classification of L/R Hand Movement EEG Signals using Advanced Feature Extraction and Machine Learning

    Directory of Open Access Journals (Sweden)

    Mohammad H. Alomari

    2013-07-01

    Full Text Available In this paper, we propose an automated computer platform for the purpose of classifying Electroencephalography (EEG signals associated with left and right hand movements using a hybrid system that uses advanced feature extraction techniques and machine learning algorithms. It is known that EEG represents the brain activity by the electrical voltage fluctuations along the scalp, and Brain-Computer Interface (BCI is a device that enables the use of the brain’s neural activity to communicate with others or to control machines, artificial limbs, or robots without direct physical movements. In our research work, we aspired to find the best feature extraction method that enables the differentiation between left and right executed fist movements through various classification algorithms. The EEG dataset used in this research was created and contributed to PhysioNet by the developers of the BCI2000 instrumentation system. Data was preprocessed using the EEGLAB MATLAB toolbox and artifacts removal was done using AAR. Data was epoched on the basis of Event-Related (De Synchronization (ERD/ERS and movement-related cortical potentials (MRCP features. Mu/beta rhythms were isolated for the ERD/ERS analysis and delta rhythms were isolated for the MRCP analysis. The Independent Component Analysis (ICA spatial filter was applied on related channels for noise reduction and isolation of both artifactually and neutrally generated EEG sources. The final feature vector included the ERD, ERS, and MRCP features in addition to the mean, power and energy of the activations of the resulting Independent Components (ICs of the epoched feature datasets. The datasets were inputted into two machine-learning algorithms: Neural Networks (NNs and Support Vector Machines (SVMs. Intensive experiments were carried out and optimum classification performances of 89.8 and 97.1 were obtained using NN and SVM, respectively. This research shows that this method of feature extraction

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

    Directory of Open Access Journals (Sweden)

    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.

  7. [Proposal and preliminary validation of a check-list for the assessment of occupational exposure to repetitive movements of the upper lims].

    Science.gov (United States)

    Colombini, D; Occhipinti, E; Cairoli, S; Baracco, A

    2000-01-01

    Over the last few years the Authors developed and implemented, a specific check-list for a "rapid" assessment of occupational exposure to repetitive movements and exertion of the upper limbs, after verifying the lack of such a tool which also had to be coherent with the latest data in the specialized literature. The check-list model and the relevant application procedures are presented and discussed. The check-list was applied by trained factory technicians in 46 different working tasks where the OCRA method previously proposed by the Authors was also applied by independent observers. Since 46 pairs of observation data were available (OCRA index and check-list score) it was possible to verify, via parametric and nonparametric statistical tests, the level of association between the two variables and to find the best simple regression function (exponential in this case) of the OCRA index from the check-list score. By means of this function, which was highly significant (R2 = 0.98, p check-list score which better corresponded to the critical values (for exposure assessment) of the OCRA index looked for. The following correspondance values between OCRA Index and check-list were then established with a view to classifying exposure levels. The check-list "critical" scores were established considering the need for obtaining, in borderline cases, a potential effect of overestimation of the exposure level. On the basis of practical application experience and the preliminary validation results, recommendations are made and the caution needed in the use of the check-list is suggested.

  8. Spatial Concept Learning in Preschool Children: Motoric Experiences and Verbal Repetition as Adjuncts to Passive Listening.

    Science.gov (United States)

    And Others; Worthington, R. Kirby

    1980-01-01

    Thirty-two preschool children were matched by age, sex, and pretest scores on spatial concept knowledge. Four groups were (1) instruction (see and hear) only, (2) verbal repetition, (3) fine motor treatment (hand manipulation), and (4) gross motor treatment (body movement). There was no difference in performance between groups given instruction…

  9. Electromyographic bridge for promoting the recovery of hand movements in subacute stroke patients: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Yu-Xuan Zhou

    2017-08-01

    Full Text Available Objective: The electromyographic bridge (EMGB detects surface electromyographic signals from a non-paretic limb. It then generates electric pulse trains according to the electromyographic time domain features, which can be used to stimulate a paralysed or paretic limb in real time. This strategy can be used for the contralateral control of neuromuscular electrical stimulation (NMES to improve motor function after stroke. The aim of this study was to compare the treat-ment effects of EMGB vs cyclic NMES on wrist and finger impairments in subacute stroke patients. Methods: A total of 42 hemiplegic patients within 6 months of their cerebrovascular accidents were randomly assigned to 4-week treatments with EMGB or cyclic NMES. Each group underwent a standard rehabilitation programme and 10 sessions per week of hand training with EMGB or cyclic NMES. Outcome measures were: Brunnstrom stage, upper extremity components of the Fugl-Meyer Assessment, Motor Status Scale, voluntary surface electromyographic ratio and active range of motion of the wrist and finger joints. Results: The EMGB group showed significantly greater improvements than the cyclic NMES group on the following measures: Brunnstrom stages for the hand, upper extremity – Fugl-Meyer Assessment, Motor Status Scale, and the voluntary surface electromyographic ratio of wrist and finger extensors. Eleven and 4 participants of the EMGB group who had no active wrist and finger movements, respectively, at the start of the treatment could perform measurable wrist and finger extensions after EMGB training. The corresponding numbers in the cyclic NMES group were only 4 and 1. Conclusion: In the present group of subacute stroke patients, the results favour EMGB over cyclic NMES for augmenting the recovery of volitional wrist and finger motion.

  10. Effects of observation of hand movements reflected in a mirror on cortical activation in patients with stroke.

    Science.gov (United States)

    Chang, Moon-Young; Kim, Hwan-Hee; Kim, Kyeong-Mi; Oh, Jae-Seop; Jang, Chel; Yoon, Tae-Hyung

    2017-01-01

    [Purpose] The purpose of this study was to examine what changes occur in brain waves when patients with stroke receive mirror therapy intervention. [Subjects and Methods] The subjects of this study were 14 patients with stroke (6 females and 8 males). The subjects were assessed by measuring the alpha and beta waves of the EEG (QEEG-32 system CANS 3000). The mirror therapy intervention was delivered over the course of four weeks (a total of 20 sessions). [Results] Relative alpha power showed statistically significant differences in the F3, F4, O1, and O2 channels in the situation comparison and higher for hand observation than for mirror observation. Relative beta power showed statistically significant differences in the F3, F4, C3, and C4 channels. [Conclusion] This study analyzed activity of the brain in each area when patients with stroke observed movements reflected in a mirror, and future research on diverse tasks and stimuli to heighten activity of the brain should be carried out.

  11. Brain activation during manipulation of the myoelectric prosthetic hand: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Maruishi, Masaharu; Tanaka, Yoshiyuki; Muranaka, Hiroyuki; Tsuji, Toshio; Ozawa, Yoshiaki; Imaizumi, Satoshi; Miyatani, Makoto; Kawahara, Junichiro

    2004-04-01

    Neuroimaging data, particularly functional magnetic resonance imaging (fMRI) findings, have not been reported in users of the myoelectric or electromyographic (EMG) prosthetic hand. We developed a virtual EMG prosthetic hand system to eliminate mutual signal noise interference between fMRI imaging and the EMG prosthesis. We used fMRI to localize activation in the human brain during manipulation of the virtual EMG prosthetic hand. Fourteen right-handed normal subjects were instructed to perform repetitive grasping with the right hand with eyes closed (CEG); repetitive grasping with the right hand with eyes open to obtain visual feedback of their own hand movement (OEG); and repetitive grasping with the virtual EMG prosthetic hand with the eyes open to obtain visual feedback of the prosthetic hand movement (VRG). The specific site activated during manipulation of the EMG prosthetic hand was the right ventral premotor cortex. Both paradigms with visual feedback also (OEG and VRG) demonstrated activation in the right posterior parietal cortex. The center of activation of the right posterior parietal cortex shifted laterally for visual feedback with the virtual EMG prosthetic hand compared to a subject's own hand. The results suggest that the EMG prosthetic hand might be recognized in the brain as a high-performance alternative to a real hand, being controlled through a "mirror system" in the brain.

  12. State-based decoding of hand and finger kinematics using neuronal ensemble and LFP activity during dexterous reach-to-grasp movements.

    Science.gov (United States)

    Aggarwal, Vikram; Mollazadeh, Mohsen; Davidson, Adam G; Schieber, Marc H; Thakor, Nitish V

    2013-06-01

    The performance of brain-machine interfaces (BMIs) that continuously control upper limb neuroprostheses may benefit from distinguishing periods of posture and movement so as to prevent inappropriate movement of the prosthesis. Few studies, however, have investigated how decoding behavioral states and detecting the transitions between posture and movement could be used autonomously to trigger a kinematic decoder. We recorded simultaneous neuronal ensemble and local field potential (LFP) activity from microelectrode arrays in primary motor cortex (M1) and dorsal (PMd) and ventral (PMv) premotor areas of two male rhesus monkeys performing a center-out reach-and-grasp task, while upper limb kinematics were tracked with a motion capture system with markers on the dorsal aspect of the forearm, hand, and fingers. A state decoder was trained to distinguish four behavioral states (baseline, reaction, movement, hold), while a kinematic decoder was trained to continuously decode hand end point position and 18 joint angles of the wrist and fingers. LFP amplitude most accurately predicted transition into the reaction (62%) and movement (73%) states, while spikes most accurately decoded arm, hand, and finger kinematics during movement. Using an LFP-based state decoder to trigger a spike-based kinematic decoder [r = 0.72, root mean squared error (RMSE) = 0.15] significantly improved decoding of reach-to-grasp movements from baseline to final hold, compared with either a spike-based state decoder combined with a spike-based kinematic decoder (r = 0.70, RMSE = 0.17) or a spike-based kinematic decoder alone (r = 0.67, RMSE = 0.17). Combining LFP-based state decoding with spike-based kinematic decoding may be a valuable step toward the realization of BMI control of a multifingered neuroprosthesis performing dexterous manipulation.

  13. Effect of robotic-assisted three-dimensional repetitive motion to improve hand motor function and control in children with handwriting deficits: a nonrandomized phase 2 device trial.

    Science.gov (United States)

    Palsbo, Susan E; Hood-Szivek, Pamela

    2012-01-01

    We explored the efficacy of robotic technology in improving handwriting in children with impaired motor skills. Eighteen participants had impairments arising from cerebral palsy (CP), autism spectrum disorder (ASD), attention deficit disorder (ADD), attention deficit hyperactivity disorder (ADHD), or other disorders. The intervention was robotic-guided three-dimensional repetitive motion in 15-20 daily sessions of 25-30 min each over 4-8 wk. Fine motor control improved for the children with learning disabilities and those ages 9 or older but not for those with CP or under age 9. All children with ASD or ADHD referred for slow writing speed were able to increase speed while maintaining legibility. Three-dimensional, robot-assisted, repetitive motion training improved handwriting fluidity in children with mild to moderate fine motor deficits associated with ASD or ADHD within 10 hr of training. This dosage may not be sufficient for children with CP. Copyright © 2012 by the American Occupational Therapy Association, Inc.

  14. Stereotypic movement disorders.

    Science.gov (United States)

    Singer, Harvey S

    2011-01-01

    Stereotypic movements are repetitive, rhythmic, fixed, patterned in form, amplitude, and localization, but purposeless (e.g., hand shaking, waving, body rocking, head nodding). They are commonly seen in children; both in normal children (primary stereotypy) and in individuals with additional behavioral or neurological signs and symptoms (secondary stereotypy). They should be differentiated from compulsions (OCD), tics (tic disorders), trichotillomania, skin picking disorder, or the direct physiological effect of a substance. There is increasing evidence to support a neurobiological mechanism. Response to behavioral and pharmacological therapies is variable.

  15. Different distal-proximal movement balances in right- and left-hand writing may hint at differential premotor cortex involvement

    NARCIS (Netherlands)

    Potgieser, A. R. E.; de Jong, B. M.

    2011-01-01

    Right-handed people generally write with their right hand. Language expressed in script is thus performed with the hand also preferred for skilled motor tasks. This may suggest an efficient functional interaction between the language area of Broca and the adjacent ventral premotor cortex (PMv) in th

  16. Different distal-proximal movement balances in right- and left-hand writing may hint at differential premotor cortex involvement

    NARCIS (Netherlands)

    Potgieser, A. R. E.; de Jong, B. M.

    2011-01-01

    Right-handed people generally write with their right hand. Language expressed in script is thus performed with the hand also preferred for skilled motor tasks. This may suggest an efficient functional interaction between the language area of Broca and the adjacent ventral premotor cortex (PMv) in th

  17. Long-lasting contralateral motor cortex excitability is increased by unilateral hand movement that triggers electrical stimulation of opposite homologous muscles.

    Science.gov (United States)

    Schmidt, Matthew W; Hinder, Mark R; Summers, Jeffery J; Garry, Michael I

    2011-01-01

    Long-term changes in the motor cortex can be induced by practicing motor tasks with simultaneous application of peripheral nerve stimulation. This combination may augment motor rehabilitation after stroke but has been used primarily during contraction of the affected hand. The authors tested the effect of a right hand movement that electrically stimulated left hand contraction on right motor cortex excitability. Three tasks were used in 15 healthy subjects--a motor and stimulation task (MS(task)), stimulation only task (S(task)), and motor only task (M(task)). The MS(task) consisted of isometric thumb abduction of the right hand that triggered paired electrical stimulation of the left abductor pollicis brevis (APB) and first dorsal interosseus (FDI) motor points. The S(task) was performed 1 week later and matched the stimulation received in the MS(task). The M(task) was performed as a control. Transcranial magnetic stimulation applied to the right motor cortex assessed corticospinal excitability, short latency intracortical inhibition, and intracortical facilitation of the FDI and APB before, immediately after, and 30 minutes after task performance. Corticospinal excitability increased in the FDI and APB following the MS(task) but not following the S(task) or M(task). The increased excitability present 30 minutes after the MS(task) also correlated with excitability measures recorded 1 week later. A bilateral motor and electrical stimulation task can drive persistent adaptation within the corticospinal system. Hemiplegic subjects who have poor voluntary movement of the affected hand may be able to contract the unaffected hand to activate and train homologous movements.

  18. Proprioception contributes to the sense of agency during visual observation of hand movements: evidence from temporal judgments of action

    DEFF Research Database (Denmark)

    Balslev, Daniela; Cole, Jonathan; Miall, R Chris

    2007-01-01

    The ability to recognize visually one's own movement is important for motor control and, through attribution of agency, for social interactions. Agency of actions may be decided by comparisons of visual feedback, efferent signals, and proprioceptive inputs. Because the ability to identify one's own...... visual feedback from passive movements is decreased relative to active movements, or in some cases is even absent, the role of proprioception in self-recognition has been questioned. Proprioception during passive and active movements may, however, differ, and so to address any role for proprioception...... synchronously or asynchronously with a random delay, and reported whether or not they felt they controlled the cursor. Movement accuracy was matched between groups. In the absence of proprioception, I.W. was less able than the control group to discriminate self- from computer-produced cursor movement based...

  19. Higher precision in pointing movements of the preferred vs. non-preferred hand is associated with an earlier occurrence of anticipatory postural adjustments

    Directory of Open Access Journals (Sweden)

    Carlo Bruttini

    2016-07-01

    Full Text Available It is a common experience to exhibit a greater dexterity when performing a pointing movement with the preferred limb vs. the non-preferred one. Here we provide evidence that the higher precision in pointing movements of the preferred vs. non-preferred hand is associated with an earlier occurrence of the Anticipatory Postural Adjustments (APAs.In this aim, we compared the APAs which stabilize the left or the right arm when performing a pen-pointing movement (prime mover Flexor Carpi Radialis. Moreover, we analysed the elbow and wrist kinematics as well as the precision of the pointing movement. The mean kinematics of wrist movement and its latency, with respect to prime mover recruitment, were similar in the two sides, while APAs in Triceps Brachii, Biceps Brachii and Anterior Deltoid were more anticipated when movements were performed with the preferred than with the non-preferred hand (60-70 vs. 20-30 ms. APAs amplitudes were comparable in the muscles of the two sides. Earlier APAs in the preferred limb were associated with a better fixation of the elbow, which showed a lower excursion, and with a less scattered pointing error (preferred: 10.1 ± 0.8 mm; non-preferred: 16.3 ± 1.7.Present results suggest that, by securing the more proximal joints dynamics, an appropriate timing of the intra-limb APAs is necessary for refining the voluntary movement precision, which is known to be scarce on the non-preferred side.

  20. Variability in spatio-temporal pattern of trapezius activity and coordination of hand-arm muscles during a sustained repetitive dynamic task

    DEFF Research Database (Denmark)

    Samani, Afshin; Srinivasan, Divya; Mathiassen, Svend Erik;

    2016-01-01

    The spatio-temporal distribution of muscle activity has been suggested to be a determinant of fatigue development. Pursuing this hypothesis, we investigated the pattern of muscular activity in the shoulder and arm during a repetitive dynamic task performed until participants' rating of perceived...... power frequency (MNF) were calculated for all EMG signals. The barycenter of RMS values over the HD-EMG grid was also determined, as well as normalized mutual information (NMI) for each pair of muscles. Cycle-to-cycle variability of these metrics was also assessed. With time, EMG RMS increased for most...... of the muscles, and MNF decreased. Trapezius activity became higher on the lateral side than on the medial side of the HD-EMG grid and the barycenter moved in a lateral direction. NMI between muscle pairs increased with time while its variability decreased. The variability of the metrics during the initial 10...

  1. [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.

  2. Variability in spatio-temporal pattern of trapezius activity and coordination of hand-arm muscles during a sustained repetitive dynamic task.

    Science.gov (United States)

    Samani, Afshin; Srinivasan, Divya; Mathiassen, Svend Erik; Madeleine, Pascal

    2017-02-01

    The spatio-temporal distribution of muscle activity has been suggested to be a determinant of fatigue development. Pursuing this hypothesis, we investigated the pattern of muscular activity in the shoulder and arm during a repetitive dynamic task performed until participants' rating of perceived exertion reached 8 on Borg's CR-10 scale. We collected high-density surface electromyogram (HD-EMG) over the upper trapezius, as well as bipolar EMG from biceps brachii, triceps brachii, deltoideus anterior, serratus anterior, upper and lower trapezius from 21 healthy women. Root-mean-square (RMS) and mean power frequency (MNF) were calculated for all EMG signals. The barycenter of RMS values over the HD-EMG grid was also determined, as well as normalized mutual information (NMI) for each pair of muscles. Cycle-to-cycle variability of these metrics was also assessed. With time, EMG RMS increased for most of the muscles, and MNF decreased. Trapezius activity became higher on the lateral side than on the medial side of the HD-EMG grid and the barycenter moved in a lateral direction. NMI between muscle pairs increased with time while its variability decreased. The variability of the metrics during the initial 10 % of task performance was not associated with the time to task termination. Our results suggest that the considerable variability in force and posture contained in the dynamic task per se masks any possible effects of differences between subjects in initial motor variability on the rate of fatigue development.

  3. How vertical hand movements impact brain activity elicited by literally and metaphorically related words: an ERP study of embodied metaphor

    National Research Council Canada - National Science Library

    Bardolph, Megan; Coulson, Seana

    2014-01-01

    ... task involving either upward- or downward- directed arm movements. ERPs were time-locked to words associated with vertical space-either literally (ascend, descend) or metaphorically (inspire, defeat...

  4. The neural consequences of repetition: clinical implications of a learning hypothesis.

    Science.gov (United States)

    Byl, N N; Melnick, M

    1997-01-01

    Repetitive strain injuries (RSIs) are difficult to treat. Some individuals with RSIs may ultimately develop chronic pain syndromes or movement problems like focal hand dystonia (FDh), a disorder of motor control manifested in a specific context during skilled, hand tasks. This paper reports on the results of four neuroplasticity studies suggesting that repetitive hand opening and closing can lead to motor control problems, measurable somatosensory changes, and problems in graphesthesia and stereognosis. The experiments support a learning hypothesis for the origin of severe RSIs, particularly FDh. This degradation in the sensory representation of the hand may not only explain the therapeutic challenge of returning these patients to work, but also provide a foundation for developing more effective physical rehabilitation strategies. Implications and conjectures for the applications of this learning hypothesis to conditions of chronic pain are also discussed.

  5. Associative cortico-cortical plasticity may affect ipsilateral finger opposition movements

    DEFF Research Database (Denmark)

    Rizzo, V; Bove, M; Naro, A;

    2011-01-01

    We have recently demonstrated that cortico-cortical paired associative stimulation (cc-PAS) can modulate interhemispheric inhibition (IHI) in the human brain. Here we further explored the after effects of cc-PAS on fine hand movements. Ten healthy right-handed volunteers received 90 paired transc...... influencing motor hand performances. These results may be relevant for future rehabilitative applications.......We have recently demonstrated that cortico-cortical paired associative stimulation (cc-PAS) can modulate interhemispheric inhibition (IHI) in the human brain. Here we further explored the after effects of cc-PAS on fine hand movements. Ten healthy right-handed volunteers received 90 paired...... transcranial stimuli to the right and left primary motor hand area (M1(HAND)) at an interstimulus interval (ISI) of 8 ms. We studied the after effects of cc-PAS on the performance of repetitive finger opposition movements of different complexity on both hands using a sensor-engineered glove. A quantitative...

  6. Are there right hemisphere contributions to visually-guided movement? : Manipulating left hand reaction time advantages in dextrals

    NARCIS (Netherlands)

    Carey, David P; Otto-de Haart, E Grace; Buckingham, Gavin; Dijkerman, H Chris; Hargreaves, Eric L; Goodale, Melvyn A

    2015-01-01

    Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right-hemisphere damage, to those using neurologically-intact particip

  7. Meditative Movement as a Treatment for Pulmonary Dysfunction in Flight Attendants Exposed to Second-Hand Cigarette Smoke: Study Protocol for a Randomized Trial

    OpenAIRE

    Payne, Peter; Zava,David; Fiering, Steven; Crane-Godreau, Mardi

    2016-01-01

    A study protocol is presented for the investigation of meditative movement (MM) as a treatment for pulmonary dysfunction in flight attendants (FA) who were exposed to second-hand cigarette smoke while flying before the smoking ban. The study will have three parts, some of which will run concurrently. The first is a data gathering and screening phase, which will gather data on pulmonary and other aspects of the health of FA, and will also serve to screen participants for the other phases. Seco...

  8. Oral and Hand Movement Speeds Are Associated with Expressive Language Ability in Children with Speech Sound Disorder

    Science.gov (United States)

    Peter, Beate

    2012-01-01

    This study tested the hypothesis that children with speech sound disorder have generalized slowed motor speeds. It evaluated associations among oral and hand motor speeds and measures of speech (articulation and phonology) and language (receptive vocabulary, sentence comprehension, sentence imitation), in 11 children with moderate to severe SSD…

  9. Oral and Hand Movement Speeds Are Associated with Expressive Language Ability in Children with Speech Sound Disorder

    Science.gov (United States)

    Peter, Beate

    2012-01-01

    This study tested the hypothesis that children with speech sound disorder have generalized slowed motor speeds. It evaluated associations among oral and hand motor speeds and measures of speech (articulation and phonology) and language (receptive vocabulary, sentence comprehension, sentence imitation), in 11 children with moderate to severe SSD…

  10. How vertical hand movements impact brain activity elicited by literally and metaphorically related words: an ERP study of embodied metaphor.

    Science.gov (United States)

    Bardolph, Megan; Coulson, Seana

    2014-01-01

    Embodied metaphor theory suggests abstract concepts are metaphorically linked to more experientially basic ones and recruit sensorimotor cortex for their comprehension. To test whether words associated with spatial attributes reactivate traces in sensorimotor cortex, we recorded EEG from the scalp of healthy adults as they read words while performing a concurrent task involving either upward- or downward- directed arm movements. ERPs were time-locked to words associated with vertical space-either literally (ascend, descend) or metaphorically (inspire, defeat)-as participants made vertical movements that were either congruent or incongruent with the words. Congruency effects emerged 200-300 ms after word onset for literal words, but not until after 500 ms post-onset for metaphorically related words. Results argue against a strong version of embodied metaphor theory, but support a role for sensorimotor simulation in concrete language.

  11. How Vertical Hand Movements Impact Brain Activity Elicited by Literally and Metaphorically Related Words: An ERP Study of Embodied Metaphor

    Directory of Open Access Journals (Sweden)

    Megan eBardolph

    2014-12-01

    Full Text Available Embodied metaphor theory suggests abstract concepts are metaphorically linked to more experientially basic ones and recruit sensorimotor cortex for their comprehension. To test whether words associated with spatial attributes reactivate traces in sensorimotor cortex, we recorded EEG from the scalp of healthy adults as they read words with while performing a concurrent task involving either upward- or downward- directed arm movements. ERPs were time-locked to words associated with vertical space – either literally (ascend, descend or metaphorically (inspire, defeat – as participants made vertical movements that were either congruent or incongruent with the words. Congruency effects emerged 200-300ms after word onset for literal words, but not until after 500ms post-onset for metaphorically related words. Results argue against a strong version of embodied metaphor theory, but support a role for sensorimotor simulation in concrete language.

  12. Trunk coordination in healthy and chronic nonspecific low back pain subjects during repetitive flexion-extension tasks: Effects of movement asymmetry, velocity and load.

    Science.gov (United States)

    Mokhtarinia, Hamid Reza; Sanjari, Mohammad Ali; Chehrehrazi, Mahshid; Kahrizi, Sedigheh; Parnianpour, Mohamad

    2016-02-01

    Multiple joint interactions are critical to produce stable coordinated movements and can be influenced by low back pain and task conditions. Inter-segmental coordination pattern and variability were assessed in subjects with and without chronic nonspecific low back pain (CNSLBP). Kinematic data were collected from 22 CNSLBP and 22 healthy volunteers during repeated trunk flexion-extension in various conditions of symmetry, velocity, and loading; each at two levels. Sagittal plane angular data were time normalized and used to calculate continuous relative phase for each data point. Mean absolute relative phase (MARP) and deviation phase (DP) were derived to quantify lumbar-pelvis and pelvis-thigh coordination patterns and variability. Statistical analysis revealed more in-phase coordination pattern in CNSLBP (p=0.005). There was less adaptation in the DP for the CNSLBP group, as shown by interactions of Group by Load (p=.008) and Group by Symmetry by Velocity (p=.03) for the DP of pelvis-thigh and lumbar-pelvis couplings, respectively. Asymmetric (pvelocity conditions (p<0.001). In conclusion, coordination pattern and variability could be influenced by trunk flexion-extension conditions. CNSLBP subjects demonstrated less adaptability of movement pattern to the demands of the flexion-extension task.

  13. Nonword Repetition and Speech Motor Control in Children

    Directory of Open Access Journals (Sweden)

    Christina Reuterskiöld

    2015-01-01

    Full Text Available This study examined how familiarity of word structures influenced articulatory control in children and adolescents during repetition of real words (RWs and nonwords (NWs. A passive reflective marker system was used to track articulator movement. Measures of accuracy were obtained during repetition of RWs and NWs, and kinematic analysis of movement duration and variability was conducted. Participants showed greater consonant and vowel accuracy during RW than NW repetition. Jaw movement duration was longer in NWs compared to RWs across age groups, and younger children produced utterances with longer jaw movement duration compared to older children. Jaw movement variability was consistently greater during repetition of NWs than RWs in both groups of participants. The results indicate that increases in phonological short-term memory demands affect articulator movement. This effect is most pronounced in younger children. A range of skills may develop during childhood, which supports NW repetition skills.

  14. Sulindac attenuates valproic acid-induced oxidative stress levels in primary cultured cortical neurons and ameliorates repetitive/stereotypic-like movement disorders in Wistar rats prenatally exposed to valproic acid.

    Science.gov (United States)

    Zhang, Yinghua; Yang, Cailing; Yuan, Guoyan; Wang, Zhongping; Cui, Weigang; Li, Ruixi

    2015-01-01

    Accumulating evidence suggests that anti-inflammatory agents and antioxidants have neuroprotective properties and may be beneficial in the treatment of neurodevelopental disorders, such as autism. In the present study, the possible neuroprotective properties of sulindac, a non-steroidal anti-inflammatory drug (NSAID), were investigated in vitro using cultured cortical neurons with valproic acid (VPA)-induced neurotoxicity, as well as in vivo through the behavioral analysis of rats prenatally exposed to VPA as a model of autism. VPA induced 4-hydroxynonenal (4-HNE) expression, reactive oxygen species (ROS) generation and decreased cell viability in primary cultured cortical neurons established from timed-pregnant (embryonic day 18) Wistar rat pups. However, co-incubation of the neurons with VPA and sulindac reduced oxidative stress and increased cell viability. The rats were administered an intraperitoneal injection with one of the following: VPA, sulindac, VPA and sulindac, or physiological saline, and their offspring were subjected to the open field test. During the test trials, repetitive/stereotypic-like movements for each rat were recorded and analyzed. The results revealed that treatment with both sulindac and VPA reduced the VPA-induced repetitive/stereotypic-like activity and the sulindac and VPA-treated animals responded better in the open field test compared to the VPA-treated animals. The results from the present study demonstrate that the antioxidant properties of sulindac may prove to be beneficial in the treatment of autism, suggesting that the upregulation of the Wnt/β-catenin signaling pathway disrupts oxidative homeostasis and facilitates susceptibility to autism.

  15. Online control of a humanoid robot through hand movement imagination using CSP and ECoG based features.

    Science.gov (United States)

    Kapeller, C; Gergondet, P; Kamada, K; Ogawa, H; Takeuchi, F; Ortner, R; Pruckl, R; Kheddar, A; Scharinger, J; Guger, C

    2015-08-01

    Intention recognition through decoding brain activity could lead to a powerful and independent Brain-Computer-Interface (BCI) allowing for intuitive control of devices like robots. A common strategy for realizing such a system is the motor imagery (MI) BCI using electroencephalography (EEG). Changing to invasive recordings like electrocorticography (ECoG) allows extracting very robust features and easy introduction of an idle state, which might simplify the mental task and allow the subject to focus on the environment. Especially for multi-channel recordings like ECoG, common spatial patterns (CSP) provide a powerful tool for feature optimization and dimensionality reduction. This work focuses on an invasive and independent MI BCI that allows triggering from an idle state, and therefore facilitates tele-operation of a humanoid robot. The task was to lift a can with the robot's hand. One subject participated and reached 95.4 % mean online accuracy after six runs of 40 trials. To our knowledge, this is the first online experiment with a MI BCI using CSPs from ECoG signals.

  16. The influence of action execution on end-state comfort and underlying movement kinematics: An examination of right and left handed participants.

    Science.gov (United States)

    Scharoun, S M; Gonzalez, D A; Bryden, P J; Roy, E A

    2016-02-01

    People typically move in an anticipatory manner, planning the intended action in advance to minimize the energy costs associated with producing the action (e.g., Rosenbaum et al., 2009). This is exemplified behaviorally in the end-state comfort effect, which is characterized by the selection of an uncomfortable initial posture to enable a comfortable posture upon completion of the movement (Rosenbaum et al., 1990). The main objective of this study was to further investigate the end-state comfort effect in left- and right-handers (N=20). More specifically, to: (a) understand the influence of mode of action execution; and (b) delineate the role of handedness. The overturned glass task (Fischman, 1997) was used as means of assessment, where participants were asked to demonstrate picking up a glass to pour water in four modes of execution: (1) pantomime without a stimulus; (2) pantomime with image of the glass as a guide; (3) pantomime with glass as a guide; and (4) grasping the glass. End-state comfort was displayed regardless of mode of execution, hand used to complete the task or handedness group. However, kinematic analysis revealed distinct differences, highlighting how movement parameters are altered as a result the mode of action execution. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Influences of hand dominance on the maintenance of benefits after home-based modified constraint-induced movement therapy in individuals with stroke

    Directory of Open Access Journals (Sweden)

    Renata C. M. Lima

    2014-10-01

    Full Text Available Objective: To investigate the influence of hand dominance on the maintenance of gains after home-based modified constraint-induced movement therapy (mCIMT. Method: Aprevious randomized controlled trial was conducted to examine the addition of trunk restraint to the mCIMT. Twenty-two chronic stroke survivors with mild to moderate motor impairments received individual home-based mCIMT with or without trunk restraints, five times per week, three hours daily over two weeks. In this study, the participants were separated into dominant group, which had their paretic upper limb as dominant before the stroke (n=8, and non-dominant group (n=14 for analyses. The ability to perform unimanual tasks was measured by the Wolf Motor Function Test (WMFT and the Motor Activity Log (MAL, whereas the capacity to perform bimanual tasks was measured using the Bilateral Activity Assessment Scale (BAAS. Results: Analysis revealed significant positive effects on the MAL amount of use and quality of the movement scales, as well as on the BAAS scores after intervention, with no differences between groups. Both groups maintained the bimanual improvements during follow-ups (BAAS-seconds 0.1, 95% CI -10.0 to 10.0, however only the dominant group maintained the unilateral improvements (MAL-amount of use: 1.5, 95% CI 0.7 to 2.3; MAL-quality: 1.3, 95% CI 0.5 to 2.1. Conclusions: Upper limb dominance did not interfere with the acquisition of upper limb skills after mCIMT. However, the participants whose paretic upper limb was dominant demonstrated better abilities to maintain the unilateral gains. The bilateral improvements were maintained, regardless of upper limb dominance.

  18. 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.

  19. 星状神经节阻滞改善肩手综合征的水肿及关节活动度%Block of ganglion stellatum on improving edema and range of movement in shoulder- hand syndrome

    Institute of Scientific and Technical Information of China (English)

    曾西; 陈尚康; 关晨霞; 姜丽; 王留根

    2003-01-01

    INTRODUCTION:Shoulder- hand syndrome(SHS) also called reflective sympathetic malnutrition is a common syndrome and often seen in stroke paralysis,which early manifestation is sudden edema of hand,pain,increased skin temperature,shoulder pain.If treatment is prolonged,muscle atrophy of hand and permanent loss of range of movement might occure.Comprehensive rehabilitation treatment has a good effect on SHS.In this article,effect of block of ganglion stellatum on SHS is observed on base of comprehensive rehabilitation treatment.

  20. Changes in cortical field potentials during learning processes of go/no-go reaction time hand movement with tone discrimination in the monkey.

    Science.gov (United States)

    Gemba, H

    1993-09-03

    Field potentials were recorded with electrodes implanted in various cortical areas while a monkey acquired a task of go/no-go reaction time hand movement with discrimination between tone stimuli of different frequencies. After a few weeks of training, a surface-negative, depth-positive (s-N, d-P) potential (no-go potential) emerged in the dorsal bank of the principal sulcus. As the potential increased in size in 1-3 months, the monkey gradually discriminated between go and no-go stimuli. The no-go potential is considered to be related to judgement not to move and suppression of motor execution. In the superior temporal gyrus, a s-N, d-P potential at a shorter latency than the no-go potential augmented in size on both go and no-go trials, as the monkey learned the discrimination task. The s-N, d-P potential in this gyrus may reflect an information processing prior to the discrimination in the prefrontal cortex.

  1. Meditative Movement as a treatment for pulmonary dysfunction in flight attendants exposed to second-hand cigarette smoke: Study protocol for a randomized trial.

    Directory of Open Access Journals (Sweden)

    Peter ePayne

    2016-03-01

    Full Text Available A study protocol is presented for the investigation of Meditative Movement (MM as a treatment for pulmonary dysfunction in Flight Attendants (FA who were exposed to second-hand cigarette smoke (SHCS while flying before the smoking ban. The study will have three parts, some of which will run concurrently. The first is a data gathering and screening phase, which will gather data on pulmonary and other aspects of the health of FA, and will also serve to screen participants for the other phases. Second is an exercise selection phase, in which a variety of MM exercises will be taught, over a 16-week period, to a cohort of 20 FA. A subset of these exercises will be selected on the basis of participant feedback on effectiveness and compliance. Third is a 52-week randomized controlled trial (RCT to evaluate the effectiveness of a digitally delivered form of the previously selected exercises on a group of 20 FA, as compared with an attention control group. Outcome measures to be used in all three parts of the study include the six-minute walk test as a primary measure, as well as a range of biomarkers, tests and questionnaires documenting hormonal, cardio-respiratory, autonomic and affective state. This study is registered at ClinicalTrials.gov. Identifier: NCT02612389.

  2. Meditative Movement as a Treatment for Pulmonary Dysfunction in Flight Attendants Exposed to Second-Hand Cigarette Smoke: Study Protocol for a Randomized Trial.

    Science.gov (United States)

    Payne, Peter; Zava, David; Fiering, Steven; Crane-Godreau, Mardi

    2016-01-01

    A study protocol is presented for the investigation of meditative movement (MM) as a treatment for pulmonary dysfunction in flight attendants (FA) who were exposed to second-hand cigarette smoke while flying before the smoking ban. The study will have three parts, some of which will run concurrently. The first is a data gathering and screening phase, which will gather data on pulmonary and other aspects of the health of FA, and will also serve to screen participants for the other phases. Second is an exercise selection phase, in which a variety of MM exercises will be taught, over a 16-week period, to a cohort of 20 FA. A subset of these exercises will be selected on the basis of participant feedback on effectiveness and compliance. Third is a 52-week randomized controlled trial to evaluate the effectiveness of a digitally delivered form of the previously selected exercises on a group of 20 FA, as compared with an attention control group. Outcome measures to be used in all three parts of the study include the 6-min walk test as a primary measure, as well as a range of biomarkers, tests, and questionnaires documenting hormonal, cardio-respiratory, autonomic, and affective state. This study is registered at ClinicalTrials.gov. Identifier: NCT02612389.

  3. "Apraxic dysgraphia" in a 15-year-old left-handed patient: disruption of the cerebello-cerebral network involved in the planning and execution of graphomotor movements.

    Science.gov (United States)

    Mariën, Peter; de Smet, Eric; de Smet, Hyo Jung; Wackenier, Peggy; Dobbeleir, Andre; Verhoeven, Jo

    2013-02-01

    Apraxic agraphia is a peripheral writing disorder caused by neurological damage. It induces a lack or loss of access to the motor engrams that plan and programme the graphomotor movements necessary to produce written output. The neural network subserving handwriting includes the superior parietal region, the dorsolateral and medial premotor cortex and the thalamus of the dominant hemisphere. Recent studies indicate that the cerebellum may be involved as well. To the best of our knowledge, apraxic agraphia has not been described on a developmental basis. This paper reports the clinical, neurocognitive and (functional) neuroimaging findings of a 15-year-old left-handed patient with an isolated, non-progressive developmental handwriting disorder consistent with a diagnosis of "apraxic dysgraphia". Gross motor coordination problems were objectified as well but no signs of cerebellar, sensorimotor or extrapyramidal dysfunction of the writing limb were found to explain the apraxic phenomena. Brain MRI revealed no supra- and infratentorial damage but quantified Tc-99m-ECD SPECT disclosed decreased perfusion in the anatomoclinically suspected prefrontal and cerebellar brain regions crucially involved in the planning and execution of skilled motor actions. This pattern of functional depression seems to support the hypothesis that "apraxic dysgraphia" might reflect incomplete maturation of the cerebello-cerebral network involved in handwriting. In addition, it is hypothesized that "apraxic dysgraphia" may have to be considered to represent a distinct nosological category within the group of the developmental dyspraxias following dysfunction of the cerebello-cerebral network involved in planned actions.

  4. 基于动态阈值的肌电假手动作控制方法研究%Movement Pattern Control for Prosthetic Hand Based on a Method of Dynamic Threshold

    Institute of Scientific and Technical Information of China (English)

    喻洪流; 胡加华

    2011-01-01

    由于构成肌电信号采集电路的电子元器件性能不可能完全对称及干扰信号的存在,有时会导致两路肌电信号发生阈值不一致。这时仍采用固定阈值来对两路肌电信号控制的动作进行判别,会导致动作的误判率增加。为了提高对假手动作判别的正确率,本文提出了利用动态阈值对假手动作进行判别。实验结果表明,利用动态阈值对假手动作进行判别,能够提高对动作判别的正确率达约10%。%Due to the function asymmetry of electrical components used for EMG signal acquisition circuit and the existing of undesired signals, sometimes thresholds for judging EMG's occur may be incongruent. If a fixed threshold is used to recognize Prosthetic Hand's movement,the matching rate of prosthetic hand's movement pattern recognition will be increased. In order to improve prosthetic hand's movement pattern recognition, a method of dynamic threshold was used to recognize the prosthetic hand's movement. The exprimental results showed that the method of dynamic threshold can obviously improve Prosthetic Hand's movement pattern recognition by about 10%.

  5. Effectiveness of a Novel Qigong Meditative Movement Practice for Impaired Health in Flight Attendants Exposed to Second-Hand Cigarette Smoke

    Science.gov (United States)

    Payne, Peter; Fiering, Steven; Leiter, James C.; Zava, David T.; Crane-Godreau, Mardi A.

    2017-01-01

    This single-arm non-randomized pilot study explores an intervention to improve the health of flight attendants (FA) exposed to second-hand cigarette smoke prior to the smoking ban on commercial airlines. This group exhibits an unusual pattern of long-term pulmonary dysfunction. We report on Phase I of a two-phase clinical trial; the second Phase will be a randomized controlled trial testing digital delivery of the intervention. Subjects were recruited in the Northeastern US; testing and intervention were administered in 4 major cities. The intervention involved 12 h of training in Meditative Movement practices. Based on recent research on the effects of nicotine on fear learning, and the influence of the autonomic nervous system on immune function, our hypothesis was that this training would improve autonomic function and thus benefit a range of health measures. Primary outcomes were the 6-min walk test and blood levels of C-reactive protein. Pulmonary, cardiovascular, autonomic, and affective measures were also taken. Fourteen participants completed the training and post-testing. There was a 53% decrease in high sensitivity C-Reactive Protein (p ≤ 0.05), a 7% reduction in systolic blood pressure (p ≤ 0.05), a 13% increase in the 6-min walk test (p ≤ 0.005), and significant positive changes in several other outcomes. These results tend to confirm the hypothesized benefits of MM training for this population, and indicate that autonomic function may be important in the etiology and treatment of their symptoms. No adverse effects were reported. This trial is registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT02612389/), and is supported by a grant from the Flight Attendant Medical Research Institute (FAMRI). PMID:28270757

  6. Effectiveness of a Novel Qigong Meditative Movement Practice for Impaired Health in Flight Attendants Exposed to Second-Hand Cigarette Smoke.

    Science.gov (United States)

    Payne, Peter; Fiering, Steven; Leiter, James C; Zava, David T; Crane-Godreau, Mardi A

    2017-01-01

    This single-arm non-randomized pilot study explores an intervention to improve the health of flight attendants (FA) exposed to second-hand cigarette smoke prior to the smoking ban on commercial airlines. This group exhibits an unusual pattern of long-term pulmonary dysfunction. We report on Phase I of a two-phase clinical trial; the second Phase will be a randomized controlled trial testing digital delivery of the intervention. Subjects were recruited in the Northeastern US; testing and intervention were administered in 4 major cities. The intervention involved 12 h of training in Meditative Movement practices. Based on recent research on the effects of nicotine on fear learning, and the influence of the autonomic nervous system on immune function, our hypothesis was that this training would improve autonomic function and thus benefit a range of health measures. Primary outcomes were the 6-min walk test and blood levels of C-reactive protein. Pulmonary, cardiovascular, autonomic, and affective measures were also taken. Fourteen participants completed the training and post-testing. There was a 53% decrease in high sensitivity C-Reactive Protein (p ≤ 0.05), a 7% reduction in systolic blood pressure (p ≤ 0.05), a 13% increase in the 6-min walk test (p ≤ 0.005), and significant positive changes in several other outcomes. These results tend to confirm the hypothesized benefits of MM training for this population, and indicate that autonomic function may be important in the etiology and treatment of their symptoms. No adverse effects were reported. This trial is registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT02612389/), and is supported by a grant from the Flight Attendant Medical Research Institute (FAMRI).

  7. A phonetic approach to consonant repetition in early words.

    Science.gov (United States)

    Kim, Namhee; Davis, Barbara L

    2015-08-01

    The goal of this study was to evaluate movement-based principles for understanding early speech output patterns. Consonant repetition patterns within children's actual productions of word forms were analyzed using spontaneous speech data from 10 typically developing American-English learning children between 12 and 36 months of age. Place of articulation, word level patterns, and developmental trends in CVC and CVCV repeated word forms were evaluated. Labial and coronal place repetitions dominated. Regressive repetition (e.g., [gag] for "dog") occurred frequently in CVC but not in CVCV word forms. Consonant repetition decreased over time. However, the children produced sound types available reported as being within young children's production system capabilities in consonant repetitions in all time periods. Findings suggest that a movement-based approach can provide a framework for comprehensively characterizing consonant place repetition patterns in early speech development.

  8. Precision markedly attenuates repetitive lift capacity.

    Science.gov (United States)

    Collier, Brooke R; Holland, Laura; McGhee, Deirdre; Sampson, John A; Bell, Alison; Stapley, Paul J; Groeller, Herbert

    2014-01-01

    This study investigated the effect of precision on time to task failure in a repetitive whole-body manual handling task. Twelve participants were required to repetitively lift a box weighing 65% of their single repetition maximum to shoulder height using either precise or unconstrained box placement. Muscle activity, forces exerted at the ground, 2D body kinematics, box acceleration and psychophysical measures of performance were recorded until task failure was reached. With precision, time to task failure for repetitive lifting was reduced by 72%, whereas the duration taken to complete a single lift and anterior deltoid muscle activation increased by 39% and 25%, respectively. Yet, no significant difference was observed in ratings of perceived exertion or heart rate at task failure. In conclusion, our results suggest that when accuracy is a characteristic of a repetitive manual handling task, physical work capacity will decline markedly. The capacity to lift repetitively to shoulder height was reduced by 72% when increased accuracy was required to place a box upon a shelf. Lifting strategy and muscle activity were also modified, confirming practitioners should take into consideration movement precision when evaluating the demands of repetitive manual handling tasks.

  9. Muscular coordination of biceps brachii and brachioradialis in elbow flexion with respect to hand position

    Directory of Open Access Journals (Sweden)

    Tim eKleiber

    2015-08-01

    Full Text Available Contribution of synergistic muscles towards specific movements over multi joint systems may change with varying position of distal or proximal joints. Purpose of this study is to reveal the relationship of muscular coordination of brachioradialis and biceps brachii during elbow flexion with respect to hand position and biomechanical advantages and disadvantages of biceps brachii. A group of 16 healthy subjects has been advised to perform 20 repetitions of single elbow flexion movements in different hand positions (pronated, neutral and supinated. With a speed of 20°/s, simultaneously sEMG of biceps brachii and brachioradialis and kinematics of the movement were recorded in a motion analysis laboratory. Normalized to MVC the sEMG amplitudes of both muscles contributing to elbow flexion movements were compared in pronated, supinated and neutral hand position over elbow joint angle. Significant differences in the contribution of brachioradialis were found in pronated hand position compared to supinated and neutral hand position while the muscular activity of biceps brachii shows no significant changes in any hand position.In conclusion, a statistical significant dependency of the inter-muscular coordination between biceps brachii and brachioradialis during elbow flexion with respect to hand position has been observed depending on a biomechanical disadvantage of biceps brachii.

  10. A STUDY ON THE EFFECTIVENESS OF BOBATH APPROACH VERSUS CONSTRAINT INDUCED MOVEMENT THERAPY (CIMT TO IMPROVE THE ARM MOTOR FUNCTION AND THE HAND DEXTERITY FUNCTION IN POST STROKE PATIENTS

    Directory of Open Access Journals (Sweden)

    Bushra Rehman

    2015-04-01

    Full Text Available Objective: To compare the effects of the Bobath Therapy and Constraint-Induced Movement Therapy on arm motor function and hand dexterity function among stroke patients with a high level of function on the affected side. Materials and Methods: Study has conducted at the Outpatient physiotherapy department of a stroke unit. With a total of 30 patients were conveniently recruited and then randomized to Bobath Concept group and constraint-induced movement therapy group. Intervention included were the Bobath Concept group was treated for 1.5 hours per day during 5 consecutive weekdays for 4 weeks whereas the constraint-induced movement therapy group received training for 2 hours per day during 5 consecutive weekdays for 3 weeks. Outcome measures by the Wolf Motor Function Test, and Jebsen Taylor Hand Function Test. Results: The two groups were found to be homogeneous based on demographic variables and baseline measurements. There were no significant differences in Wolf Motor Function Test at post test (p = 0.861 and at follow up (p = 0.395. There is a significant improvement in JTHFT in both the groups with sight better improvement in group B (except writing components post test p=0.752and checkers at post test p=0.197 and follow up p=0.167 as compared to Group A. Conclusions: Bobath therapy and the Constraint-induced movement therapy have similar efficiencies in improving arm motor function 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 hand dexterity function.

  11. Repetitive maladaptive behavior: beyond repetition compulsion.

    Science.gov (United States)

    Bowins, Brad

    2010-09-01

    Maladaptive behavior that repeats, typically known as repetition compulsion, is one of the primary reasons that people seek psychotherapy. However, even with psychotherapeutic advances it continues to be extremely difficult to treat. Despite wishes and efforts to the contrary repetition compulsion does not actually achieve mastery, as evidenced by the problem rarely resolving without therapeutic intervention, and the difficulty involved in producing treatment gains. A new framework is proposed, whereby such behavior is divided into behavior of non-traumatic origin and traumatic origin with some overlap occurring. Repetitive maladaptive behavior of non-traumatic origin arises from an evolutionary-based process whereby patterns of behavior frequently displayed by caregivers and compatible with a child's temperament are acquired and repeated. It has a familiarity and ego-syntonic aspect that strongly motivates the person to retain the behavior. Repetitive maladaptive behavior of traumatic origin is characterized by defensive dissociation of the cognitive and emotional components of trauma, making it very difficult for the person to integrate the experience. The strong resistance of repetitive maladaptive behavior to change is based on the influence of both types on personality, and also factors specific to each. Psychotherapy, although very challenging at the best of times, can achieve the mastery wished and strived for, with the aid of several suggestions provided.

  12. Hand to hand.

    Science.gov (United States)

    Bedell, Susanna E; Graboys, Thomas B

    2002-08-01

    Examination of the hands has the potential to transform the encounter between physician and patient. Taking the hands conveys a sense of warmth and connectedness and is a means to communicate the physician's mindfulness. The hands can focus the examination on the individual patient as a complete human being, and not merely a disease or a collection of symptoms. The hands provide readily accessible information that may not be available through other evaluations, and they offer clues to a patient's physical and mental health. Commonplace observations, such as those revealed in the hands, can unravel medical mysteries and provide profound clinical insights.

  13. Handedness, repetitive transcranial magnetic stimulation and bulimic disorders.

    Science.gov (United States)

    Van den Eynde, F; Broadbent, H; Guillaume, S; Claudino, A; Campbell, I C; Schmidt, U

    2012-05-01

    Repetitive Transcranial Magnetic Stimulation (rTMS) research in psychiatry mostly excludes left-handed participants. We recruited left-handed people with a bulimic disorder and found that stimulation of the left prefrontal cortex may result in different effects in left- and right-handed people. This highlights the importance of handedness and cortex lateralisation for rTMS.

  14. Repetitive differential finger motion increases shear strain between the flexor tendon and subsynovial connective tissue.

    Science.gov (United States)

    Tat, Jimmy; Kociolek, Aaron M; Keir, Peter J

    2013-10-01

    Non-inflammatory fibrosis and thickening of the subsynovial connective tissue (SSCT) are characteristic in carpal tunnel syndrome (CTS) patients. These pathological changes have been linked to repetitive hand tasks that create shear forces between the flexor tendons and SSCT. We measured the relative motion of the flexor digitorum superficialis tendon and SSCT during two repetitive finger tasks using color Doppler ultrasound. Twelve participants performed flexion-extension cycles for 30 min with the long finger alone (differential movement) and with all four fingers together (concurrent movement). Shear strain index (SSI, a relative measure of excursion in flexion and extension) and maximum velocity ratio (MVR, the ratio of SSCT versus tendon during flexion and extension) were used to represent shear. A linear effect of exertion time was significant and corresponded with larger tendon shear in differential motion. The flexion SSI increased 20.4% from the first to the 30th minute, while MVR decreased 8.9% in flexion and 8.7% in extension. No significant changes were found during concurrent motion. These results suggest that exposure to repetitive differential finger tasks may increase the risk of shear injury in the carpal tunnel. Copyright © 2013 Orthopaedic Research Society.

  15. Grammatical Change through Repetition.

    Science.gov (United States)

    Arevart, Supot

    1989-01-01

    The effect of repetition on grammatical change in an unrehearsed talk is examined based on a case study of a single learner. It was found that repetition allows for accuracy monitoring in that errors committed in repeated contexts undergo correction. Implications for teaching are discussed. (23 references) (LB)

  16. The Negative Repetition Effect

    Science.gov (United States)

    Mulligan, Neil W.; Peterson, Daniel J.

    2013-01-01

    A fundamental property of human memory is that repetition enhances memory. Peterson and Mulligan (2012) recently documented a surprising "negative repetition effect," in which participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once. Words within a pair rhymed, and…

  17. Roles of repetitive sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bell, G.I.

    1991-12-31

    The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

  18. Roles of repetitive sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bell, G.I.

    1991-12-31

    The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

  19. Repetition and Translation Shifts

    Directory of Open Access Journals (Sweden)

    Simon Zupan

    2006-06-01

    Full Text Available Repetition manifests itself in different ways and at different levels of the text. The first basic type of repetition involves complete recurrences; in which a particular textual feature repeats in its entirety. The second type involves partial recurrences; in which the second repetition of the same textual feature includes certain modifications to the first occurrence. In the article; repetitive patterns in Edgar Allan Poe’s short story “The Fall of the House of Usher” and its Slovene translation; “Konec Usherjeve hiše”; are compared. The author examines different kinds of repetitive patterns. Repetitions are compared at both the micro- and macrostructural levels. As detailed analyses have shown; considerable microstructural translation shifts occur in certain types of repetitive patterns. Since these are not only occasional; sporadic phenomena; but are of a relatively high frequency; they reduce the translated text’s potential for achieving some of the gothic effects. The macrostructural textual property particularly affected by these shifts is the narrator’s experience as described by the narrative; which suffers a reduction in intensity.

  20. Predicate Movements in Chinese

    Science.gov (United States)

    Shou-hsin, Teng

    1975-01-01

    The movements of such higher predicates as time, locative, and complementation verbs are studied, and Tai's Predicate Placement Constraint is rejected as an incorrect account of predicate movements in Chinese. It is proposed, on the other hand, that there is only leftward movement involving predicates in Chinese. (Author)

  1. Examining Restricted and Repetitive Behaviors in Young Children with Autism Spectrum Disorder during Two Observational Contexts

    Science.gov (United States)

    Stronach, Sheri; Wetherby, Amy M.

    2014-01-01

    This prospective study of the FIRST WORDS® Project examined restricted and repetitive behaviors in a sample of 55 toddlers at a mean age of 20 months who were later diagnosed with autism spectrum disorder. Restricted and repetitive behaviors were coded using the Repetitive Movement and Restricted Interest Scales in two video-recorded observation…

  2. The alien hand syndrome

    Science.gov (United States)

    Panikkath, Deepa; Mojumder, Deb; Nugent, Kenneth

    2014-01-01

    A 77-year-old woman presented with the complaint of observing her left hand moving without her knowledge while watching television. Her left hand stroked her face and hair as if somebody was controlling it. These movements lasted only half an hour but on recovery, she had left hemiparesis. Alien hand syndrome as the presentation of cardioembolic stroke is extremely rare but can be terrifying to patients. PMID:24982566

  3. Kinematic aiming task: measuring functional changes in hand and arm movements after botulinum toxin-A injections in children with spastic hemiplegia.

    NARCIS (Netherlands)

    Rameckers, E.A.A.; Speth, L.A.; Duysens, J.E.J.; Vles, J.S.; Smits-Engelsman, B.C.M.

    2007-01-01

    OBJECTIVE: To describe different aspects of a kinematic aiming task (KAT) as a quantitative way to assess changes in arm movements within 2 wks after botulinum toxin-A (BTX-A) injections in children with spastic hemiplegia. DESIGN: Intervention study randomized clinical trial; follow-up within 4 wks

  4. Kinematic aiming task: measuring functional changes in hand and arm movements after botulinum toxin-A injections in children with spastic hemiplegia.

    NARCIS (Netherlands)

    Rameckers, E.A.A.; Speth, L.A.; Duysens, J.E.J.; Vles, J.S.; Smits-Engelsman, B.C.M.

    2007-01-01

    OBJECTIVE: To describe different aspects of a kinematic aiming task (KAT) as a quantitative way to assess changes in arm movements within 2 wks after botulinum toxin-A (BTX-A) injections in children with spastic hemiplegia. DESIGN: Intervention study randomized clinical trial; follow-up within 4 wks

  5. The effect of the height to which the hand is lifted on horizontal curvature in horizontal point-to-point movements

    NARCIS (Netherlands)

    Tuitert, I.; Mouton, L. J.; Schoemaker, M. M.; Zaal, F. T. J. M.; Bongers, R. M.

    2014-01-01

    In point-to-point reaching movements, the trajectory of the fingertip along the horizontal plane is not completely straight but slightly curved sideward. The current paper examines whether this horizontal curvature is related to the height to which the finger is lifted. Previous research suggested t

  6. Interaction of electrical stimulation and voluntary hand movement in SII and the cerebellum during simulated therapeutic functional electrical stimulation in healthy adults

    DEFF Research Database (Denmark)

    Iftime-Nielsen, Simona Denisia; Christensen, Mark Schram; Vingborg, Rune Jersin

    2012-01-01

    The therapeutic application of functional electrical stimulation (FES) has shown promising clinical results in the rehabilitation of post-stroke hemiplegia. It appears that the effect is optimal when the patterned electrical stimulation is used in close synchrony with voluntary movement, although...

  7. Spierbelasting en RSI [Muscle load and repetitive strain injury (RSI)

    NARCIS (Netherlands)

    Hoozemans, M.J.M.; Visser, B.; Huysmans, M.A.; Speklé, E.M.; Dieën, J.H. van

    2005-01-01

    This paper presents an overview of theories concerning the development of RSI (repetitive strain injury), related to muscle disorders. Movement is a noisy process. The level of noise is affected by factors such as fatigue and psychosocial stress. In order for precision movements to be made in such

  8. Trialogue: Preparation, Repetition and...

    Science.gov (United States)

    Oberg, Antoinette; And Others

    1996-01-01

    This paper interrogates both curriculum theory and the limits and potentials of textual forms. A set of overlapping discourses (a trialogue) focuses on inquiring into the roles of obsession and repetition in creating deeply interpretive locations for understanding. (SM)

  9. Robust Repetitive Controller for Fast AFM Imaging

    CERN Document Server

    Necipoglu, Serkan; Has, Yunus; Guvenc, Levent; Basdogan, Cagatay

    2012-01-01

    Currently, Atomic Force Microscopy (AFM) is the most preferred Scanning Probe Microscopy (SPM) method due to its numerous advantages. However, increasing the scanning speed and reducing the interaction forces between the probe's tip and the sample surface are still the two main challenges in AFM. To meet these challenges, we take advantage of the fact that the lateral movements performed during an AFM scan is a repetitive motion and propose a Repetitive Controller (RC) for the z-axis movements of the piezo-scanner. The RC utilizes the profile of the previous scan line while scanning the current line to achieve a better scan performance. The results of the scanning experiments performed with our AFM set-up show that the proposed RC significantly outperforms a conventional PI controller that is typically used for the same task. The scan error and the average tapping forces are reduced by 66% and 58%, respectively when the scan speed is increased by 7-fold.

  10. Interaction of electrical stimulation and voluntary hand movement in SII and the cerebellum during simulated therapeutic functional electrical stimulation in healthy adults.

    Science.gov (United States)

    Iftime-Nielsen, Simona Denisia; Christensen, Mark Schram; Vingborg, Rune Jersin; Sinkjaer, Thomas; Roepstorff, Andreas; Grey, Michael James

    2012-01-01

    The therapeutic application of functional electrical stimulation (FES) has shown promising clinical results in the rehabilitation of post-stroke hemiplegia. It appears that the effect is optimal when the patterned electrical stimulation is used in close synchrony with voluntary movement, although the neural mechanisms that underlie the clinical successes reported with therapeutic FES are unknown. One possibility is that therapeutic FES takes advantage of the sensory consequences of an internal model. Here, we investigate fMRI cortical activity when FES is combined with voluntary effort (FESVOL) and we compare this activity to that produced when FES and voluntary activity (VOL) are performed alone. FESVOL revealed greater cerebellar activity compared with FES alone and reduced activity bilaterally in secondary somatosensory areas (SII) compared with VOL alone. Reduced activity was also observed for FESVOL compared with FES alone in the angular gyrus, middle frontal gyrus and inferior frontal gyrus. These findings indicate that during the VOL condition the cerebellum predicts the sensory consequences of the movement and this reduces the subsequent activation in SII. The decreased SII activity may reflect a better match between the internal model and the actual sensory feedback. The greater cerebellar activity coupled with reduced angular gyrus activity in FESVOL compared with FES suggests that the cortex may interpret sensory information during the FES condition as an error-like signal due to the lack of a voluntary component in the movement.

  11. Effects of Wnt/β-catenin on repetitive/stereotypic-like movements in an autistic model induced by prenatal exposure to valproic acid%Wnt/β-catenin信号通路对孤独症模型大鼠重复呆板样行为的影响

    Institute of Scientific and Technical Information of China (English)

    张应花; 贾云杰; 张天然; 崔卫刚; 王中平; 小军

    2015-01-01

    Objective To investigate the effects of Wnt/β-catenin on repetitive/stereotypic-like movements in autism. Methods With an autistic model induced by prenatal exposure to valproic acid (VPA), we detected the expression of GSK-3β, β-catenin, the signaling molecules of the canonical Wnt pathway in the cerebellum of autistic rats. The expression levels of GSK-3β, phosphorylated GSK-3β, β-catenin, phosphorylated β-catenin were observed by Western blotting. The number of repetitive/stereotypic-like behaviors and time engaged in repetitive/stereotypic-like movements were observed by open field. Results The phospholated protein levels of GSK-3βwere higher, whereas those ofβ-catenin were lower in VPA-exposed group than those in the control group. In contrast, the number of repetitive/stereotypic-like behaviors and time engaged in repetitive/stereotypic-like movements were significantly higher in the animals treated with VPA than those in the control group. Conclusion Hyperkinetics and increased activity of the canonical Wnt pathway in cerebellum of autistic rats suggest that increased activity of the canonical Wnt pathway may result in repetitive/stereotypic-like mobility disorders and further contribute to the susceptibility to autism.%目的:探讨Wnt/β-catenin信号通路对孤独症发生过程中重复呆板样行为的影响。方法利用丙戊酸(valproic acid,VPA)孤独症动物模型,检测了经典Wnt信号通路关键信号分子β-catenin及其负性调节因子GSK-3β在孤独症模型大鼠小脑脑区的表达变化;同时检测孤独症模型大鼠重复呆板样行为变化。Western blotting法检测GSK-3β、β-catenin总蛋白及磷酸化蛋白表达,运用旷场实验检测重复呆板样行为持续的时间、次数。结果与对照组相比,在小脑脑区模型组GSK-3β磷酸化蛋白表达增加,β-catenin磷酸化蛋白表达减少;重复呆板样行为持续的时间、次数均增加。结论孤独症大鼠小脑

  12. Getting nowhere fast: trade-off between speed and precision in training to execute image-guided hand-tool movements.

    Science.gov (United States)

    Batmaz, Anil Ufuk; de Mathelin, Michel; Dresp-Langley, Birgitta

    2016-11-14

    The speed and precision with which objects are moved by hand or hand-tool interaction under image guidance depend on a specific type of visual and spatial sensorimotor learning. Novices have to learn to optimally control what their hands are doing in a real-world environment while looking at an image representation of the scene on a video monitor. Previous research has shown slower task execution times and lower performance scores under image-guidance compared with situations of direct action viewing. The cognitive processes for overcoming this drawback by training are not yet understood. We investigated the effects of training on the time and precision of direct view versus image guided object positioning on targets of a Real-world Action Field (RAF). Two men and two women had to learn to perform the task as swiftly and as precisely as possible with their dominant hand, using a tool or not and wearing a glove or not. Individuals were trained in sessions of mixed trial blocks with no feed-back. As predicted, image-guidance produced significantly slower times and lesser precision in all trainees and sessions compared with direct viewing. With training, all trainees get faster in all conditions, but only one of them gets reliably more precise in the image-guided conditions. Speed-accuracy trade-offs in the individual performance data show that the highest precision scores and steepest learning curve, for time and precision, were produced by the slowest starter. Fast starters produced consistently poorer precision scores in all sessions. The fastest starter showed no sign of stable precision learning, even after extended training. Performance evolution towards optimal precision is compromised when novices start by going as fast as they can. The findings have direct implications for individual skill monitoring in training programmes for image-guided technology applications with human operators.

  13. Transgenerational effects of environmental enrichment on repetitive motor behavior development.

    Science.gov (United States)

    Bechard, Allison R; Lewis, Mark H

    2016-07-01

    The favorable consequences of environmental enrichment (EE) on brain and behavior development are well documented. Much less is known, however, about transgenerational benefits of EE on non-enriched offspring. We explored whether transgenerational effects of EE might extend to the development of repetitive motor behaviors in deer mice. Repetitive motor behaviors are invariant patterns of movement that, across species, can be reduced by EE. We found that EE not only attenuated the development of repetitive behavior in dams, but also in their non-enriched offspring. Moreover, maternal behavior did not seem to mediate the transgenerational effect we found, although repetitive behavior was affected by reproductive experience. These data support a beneficial transgenerational effect of EE on repetitive behavior development and suggest a novel benefit of reproductive experience.

  14. Repetitive training for ameliorating upper limbs spasm of hemiplegic patients

    Institute of Scientific and Technical Information of China (English)

    Lin Zhu; Lin Liu; Weiqun Song

    2006-01-01

    BACKGROUND:The main aim of rehabilitation is to ameliorate motor function and use the damaged limbs in the activities of daily living.Several factors are needed in the self-recovery of the patients,and the most important one is to reduce spasm.Some mechanical repetitive movements can affect and change the excitability of motor neurons.OBJECTIVE:To observe the effect of repetitive training on ameliorating spasm of upper limbs of hemiplegic patients.DESIGN:A self-controlled observation before and after training.SETTING:Department of Rehabilitation,Xuanwu Hospital of Capital Medical University.PARTICI PANTS: Seven hemiplegic patients induced by brain injury were selected from the Department of Rehabilitation,Xuanwu Hospital,Capital Medical University from March to June in 2005.Inclusive criteria:①Agreed and able to participate in the 30-minute training of hand function; ②Without disturbance of understanding.The patients with aphasia or apraxia,manifestation of shoulder pain,and severe neurological or mental defects.For the 7 patients,the Rivermead motor assessment(RMA)scores ranged 0-10 points,the Rivermead mobility index(RMI)ranged 1-3,and modified Ashworth scale(MAS)was grade 2-4.Their horizontal extension of shoulder joint was 0°-30°,anteflextion was 0°-50°,internal rotation was 50°-90°,external rotation was 0°-10°:and the elbow joint could extend for 15°-135°.METHODS:The viva 2 serial MOTOmed exerciser(Reck Company,Germany)was used.There were three phases of A-B-A.①The phase A lasted for 1 week.The patient sat on a chair facting to the MOTOmed screen.and did the circumduction of upper limbs forwardly,30 minutes a day and 5 days a week.②The phase B lasted for 3 weeks.The training consisted of forward circumduction of upper limbs for 15 minutes.followed by backward ones for 15 minutes and 5-minute rest.③The training in the phase A was performed again for 2 weeks.The extensions of upper limbs were recorded at phase A,the extension and flexion of

  15. Decoding Grasp Movement from Monkey Premotor Cortex for Real-time Prothetic Hand Control%猴子PMd区脑电解码抓握手势及机械手实时控制

    Institute of Scientific and Technical Information of China (English)

    郑筱祥; 王怡雯; 张韶岷; 张巧生

    2016-01-01

    过去的10年,脑机接口中对上肢有关的伸解码取得了非常大的成功,这给残障人士运动康复带来了希望。但与日常生活息息相关的手部的抓握动作的研究却很少涉及。当前,在解码手势方面有很多初步的工作,但是实时的抓握手势的解码工作还没有被系统地研究过。该研究首先建立了基于非人灵长类动物的植入式脑机接口平台,训练猕猴完成伸抓动作并记录PMd区的神经信号。通过FKNN算法异步解码出4种抓握手势和休息状态。然后,利用共享控制策略驱动灵巧的机械手完成与猴子相同的动作。结果表明大部分PMd区的神经元对伸抓动作具有调和特性,利用PMd区的神经元的解码正确率可以达到97.1%。在线控制模式中,猴子手的瞬时状态能够被成功解码出来并用于机械手的控制,正确率可以达到85.1%。我们的研究为残疾人士抓握运动的康复提供了新的思路和方法。%Brain machine interfaces (BMIs) have demonstrated lots of successful arm-related reach decoding in past decades, which provide a new hope for restoring the lost motor functions for the disabled. On the other hand, the more sophisticated hand grasp movement, which is more fundamental and crucial for daily life, was less referred. Current state of arts has specified some grasp related brain areas and offline decoding results; however, online decoding grasp movement and real-time neuroprosthetic control have not been systematically investigated. In this study, we obtained neural data from the dorsal premotor cortex (PMd) when monkey reaching and grasping one of four differently shaped objects following visual cues. The four grasp gesture types with an additional resting state were classified asynchronously using a fuzzy k-nearest neighbor model, and an artificial hand was controlled online using a shared control strategy. The results showed that most of the neurons in PMd are

  16. Novel porcine repetitive elements

    Directory of Open Access Journals (Sweden)

    Nonneman Dan J

    2006-12-01

    Full Text Available Abstract Background Repetitive elements comprise ~45% of mammalian genomes and are increasingly known to impact genomic function by contributing to the genomic architecture, by direct regulation of gene expression and by affecting genomic size, diversity and evolution. The ubiquity and increasingly understood importance of repetitive elements contribute to the need to identify and annotate them. We set out to identify previously uncharacterized repetitive DNA in the porcine genome. Once found, we characterized the prevalence of these repeats in other mammals. Results We discovered 27 repetitive elements in 220 BACs covering 1% of the porcine genome (Comparative Vertebrate Sequencing Initiative; CVSI. These repeats varied in length from 55 to 1059 nucleotides. To estimate copy numbers, we went to an independent source of data, the BAC-end sequences (Wellcome Trust Sanger Institute, covering approximately 15% of the porcine genome. Copy numbers in BAC-ends were less than one hundred for 6 repeat elements, between 100 and 1000 for 16 and between 1,000 and 10,000 for 5. Several of the repeat elements were found in the bovine genome and we have identified two with orthologous sites, indicating that these elements were present in their common ancestor. None of the repeat elements were found in primate, rodent or dog genomes. We were unable to identify any of the replication machinery common to active transposable elements in these newly identified repeats. Conclusion The presence of both orthologous and non-orthologous sites indicates that some sites existed prior to speciation and some were generated later. The identification of low to moderate copy number repetitive DNA that is specific to artiodactyls will be critical in the assembly of livestock genomes and studies of comparative genomics.

  17. MIRROR MOVEMENT: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    AA. Momen

    2008-11-01

    Full Text Available Mirror movement is an interesting but often overlooked neurological soft sign;these movements are described as simultaneous contralateral, involuntary, identical movements that accompany voluntary movements. This neurologic problem is very rarely seen in children; in familial cases there is a positive history of these movements in parents, diminishing with time. Here, we have presented the case of an 11-year old girl with mirror movements in her upper limbs which interfered with her hand writing. Her neurological examination revealed normal results. In this report, we have tried to explain some of the pathophysiologic mechanisms related to these abnormal movements.Keywords:Mirror Movements, Children, Soft neurologic sign

  18. Effects of combining 2 weeks of passive sensory stimulation with active hand motor training in healthy adults.

    Directory of Open Access Journals (Sweden)

    Aija Marie Ladda

    Full Text Available The gold standard to acquire motor skills is through intensive training and practicing. Recent studies have demonstrated that behavioral gains can also be acquired by mere exposure to repetitive sensory stimulation to drive the plasticity processes. Single application of repetitive electric stimulation (rES of the fingers has been shown to improve tactile perception in young adults as well as sensorimotor performance in healthy elderly individuals. The combination of repetitive motor training with a preceding rES has not been reported yet. In addition, the impact of such a training on somatosensory tactile and spatial sensitivity as well as on somatosensory cortical activation remains elusive. Therefore, we tested 15 right-handed participants who underwent repetitive electric stimulation of all finger tips of the left hand for 20 minutes prior to one hour of motor training of the left hand over the period of two weeks. Overall, participants substantially improved the motor performance of the left trained hand by 34%, but also showed a relevant transfer to the untrained right hand by 24%. Baseline ipsilateral activation fMRI-magnitude in BA 1 to sensory index finger stimulation predicted training outcome for somatosensory guided movements: those who showed higher ipsilateral activation were those who did profit less from training. Improvement of spatial tactile discrimination was positively associated with gains in pinch grip velocity. Overall, a combination of priming rES and repetitive motor training is capable to induce motor and somatosensory performance increase and representation changes in BA1 in healthy young subjects.

  19. Hand Anatomy

    Science.gov (United States)

    ... Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is a Hand Therapist? Media Find a Hand Surgeon Home Anatomy Bones Joints Muscles Nerves Vessels Tendons Anatomy The upper extremity is ...

  20. Android Hands

    DEFF Research Database (Denmark)

    Vlachos, Evgenios; Schärfe, Henrik

    2014-01-01

    . On such occasions, android and humanoid hand models should have similar structure, functions, and performance as the human hand. In this paper we present the anatomy, and the key functionalities of the human hand followed by a literature review on android/humanoid hands for grasping and manipulating objects...

  1. REPETITIVE MANUAL OPERATIONS IN THE DAIRY SECTOR: ANALYSES AND CRITERIA FOR INTERVENTION

    Directory of Open Access Journals (Sweden)

    Pier Riccardo Porceddu

    2008-03-01

    Full Text Available For the health of workers it is necessary to consider, together with traditional risks (noise, vibrations, microclimate etc., risks deriving from repetitive movements, which can generate muscolo-skeletal disorders. These risks can be found in artisan dairies, where the limited use of machinery and the rapid successive passages for processing the milk require high-frequency repetitive manual movements. The study analysed the risks of repetitive movements for workers in a dairy, using the OCRA method. Various risk-involving operations emerged, which require the re-planning of the workplace. The proposed interventions have not involved high costs for the dairy, or a loss of productivity.

  2. Finger-specific loss of independent control of movements in musicians with focal dystonia.

    Science.gov (United States)

    Furuya, S; Altenmüller, E

    2013-09-01

    The loss of independent control of finger movements impairs the dexterous use of the hand. Focal hand dystonia is characterised by abnormal structural and functional changes at the cortical and subcortical regions responsible for individuated finger movements and by the loss of surround inhibition in the finger muscles. However, little is known about the pathophysiological impact of focal dystonia on the independent control of finger movements. Here we addressed this issue by asking pianists with and without focal dystonia to repetitively strike a piano key with one of the four fingers as fast as possible while the remaining digits kept the adjacent keys depressed. Using principal component analysis and cluster analysis to the derived keystroke data, we successfully classified pianists according to the presence or absence of dystonic symptoms with classification rates and cross-validation scores of approximately 90%. This confirmed the effects of focal dystonia on the individuated finger movements. Interestingly, the movement features that contributed to successful classification differed across fingers. Compared to healthy pianists, pianists with an affected index finger were characterised predominantly by stronger keystrokes, whereas pianists with affected middle or ring fingers exhibited abnormal temporal control of the keystrokes, such as slowness and rhythmic inconsistency. The selective alternation of the movement features indicates a finger-specific loss of the independent control of finger movements in focal dystonia of musicians.

  3. Restoration from Taishan Ganoderma after repetitive motion injury and repair of skeletal muscle micro-movement of Wushu athletes fatigue%从泰山赤灵芝对重复运动后骨骼肌微损伤修复探讨武术运动员的运动疲劳的恢复研究

    Institute of Scientific and Technical Information of China (English)

    李晨; 吕晨曦

    2014-01-01

    some repair mechanisms, Taishan Ganoderma lucidum bone to repetitive motion The muscle ultrastructure has a protective effect,Martial arts athletes in training to give appropriate treatment volume of Taishan Ganoderma drug intervention to help repair micro -damaged skeletal muscle movement,to eliminate the accumulation of skeletal muscle fatigue fatigue recovery.%目的:探讨泰山赤灵芝对大强度重复运动(力竭运动)后大鼠骨骼肌微损伤变异的修复,研究武术运动员在训练期给与适当的治疗量泰山赤灵芝药物干预有助于运动性骨骼肌微损伤的修复及运动疲劳的恢复。方法成年雄性SD大鼠52只,随机分为2组:对照组、实验组。重复运动的动物模型构建:大鼠在跑台上进行下坡跑,速度18 m/min,坡度-16度,大强度重复运动(力竭运动)。设立实验组(喂养泰山赤灵芝水煎液)、对照组,进行同样的重复力竭运动,在同一时间点分别对对照组、实验组在大强度重复运动(力竭运动)后取股四头肌,同时对实验组大鼠进行治疗量泰山赤灵芝喂养,考察该药对大强度重复运动下大鼠骨骼肌微损伤变异是否有影响,观察对照组、实验组大强度运动(重复运动)下大鼠骨骼肌超微结构变异进行研究。结果补充泰山赤灵芝后重复运动训练下大鼠骨骼肌超微结构变异研究表明:利用透射电镜对补充泰山赤灵芝后大鼠进行相同的大强度重复运动(力竭运动)后,该过程中骨骼肌超微结构变化程度看出大鼠股四头肌的微损伤有显著改善,但是仍表现为肌原纤维排列不规则,肌节不完整,Z线变细,肌丝卷曲等。结论大强度运动下骨骼肌超微结构图谱变异与骨骼肌微损伤或者疲劳存在一定的适应性机制,同时对补充泰山赤灵芝过程中可带来一定的修复机制,泰山赤灵芝对重复运动后骨骼肌超微结构具有保

  4. MIMICRY, DIFFERENCE AND REPETITION

    Directory of Open Access Journals (Sweden)

    Marcelo Mendes de Souza

    2008-07-01

    Full Text Available This article addresses Homi K. Bhabha’s concept of mimicry in a broader context, other than that of cultural studies and post-colonial studies, bringing together other concepts, such as that of Gilles Deleuze in Difference and repetition, among other texts, and other names, such as Silviano Santiago, Jorge Luís Borges, Franz Kafka and Giorgio Agamben. As a partial conclusion, the article intends to oppose Bhabha’s freudian-marxist view to Five propositions on Psychoanalysis (1973, Gilles Deleuze’s text about Psychoanalysis published right after his book The Anti-Oedipus.

  5. A soft robotic exomusculature glove with integrated sEMG sensing for hand rehabilitation.

    Science.gov (United States)

    Delph, Michael A; Fischer, Sarah A; Gauthier, Phillip W; Luna, Carlos H Martinez; Clancy, Edward A; Fischer, Gregory S

    2013-06-01

    Stroke affects 750,000 people annually, and 80% of stroke survivors are left with weakened limbs and hands. Repetitive hand movement is often used as a rehabilitation technique in order to regain hand movement and strength. In order to facilitate this rehabilitation, a robotic glove was designed to aid in the movement and coordination of gripping exercises. This glove utilizes a cable system to open and close a patients hand. The cables are actuated by servomotors, mounted in a backpack weighing 13.2 lbs including battery power sources. The glove can be controlled in terms of finger position and grip force through switch interface, software program, or surface myoelectric (sEMG) signal. The primary control modes of the system provide: active assistance, active resistance and a preprogrammed mode. This project developed a working prototype of the rehabilitative robotic glove which actuates the fingers over a full range of motion across one degree-of-freedom, and is capable of generating a maximum 15N grip force.

  6. Hand Fractures

    Science.gov (United States)

    ... Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is ... serve as a framework. This framework supports the muscles that make the wrist ... When one of these hand bones is broken (fractured), it can prevent you ...

  7. Discrimination on and Application of the Movement of Single-hand Backhand Drive and Backhand Chop in Tennis%单反抽球与反手削球的辨析和运用

    Institute of Scientific and Technical Information of China (English)

    许启愈; 高守东

    2012-01-01

    By the methods of literature review,observation and comparative analysis,the paper made an analysis on comparing the movement of single-hand backhand drive and backhand chop in tennis from the point of view of technique,biomechanics and competitive elements.The results showed that there is difference between two movements in the aspects of backswing,bat swing,hitting point,swing through,striking force,velocity,spin,arch and placement.Combining the factors of the feature of two techniques,different court,variation of tactics and opponent,the paper discussed how to apply two techniques in tennis competition effectively.%运用文献资料法、录像分析法、观察法和比较分析等方法,从技术的角度、竞技要素的角度以及生物力学的角度,对网球单反抽球与反手削球进行比较分析,发现两者之间在引拍、挥拍、击球点、随挥、击球的力量、速度、旋转、弧线以及落点等有所差异。结合两项技术的特点,再针对不同的战术、场地、对手等因素,提出如何有效运用这两项技术。

  8. Movement Disorders

    Science.gov (United States)

    ... t want them to. If you have a movement disorder, you experience these kinds of impaired movement. Dyskinesia ... movement and is a common symptom of many movement disorders. Tremors are a type of dyskinesia. Nerve diseases ...

  9. Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS)

    DEFF Research Database (Denmark)

    Lefaucheur, Jean-Pascal; André-Obadia, Nathalie; Antal, Andrea

    2014-01-01

    A group of European experts was commissioned to establish guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS) from evidence published up until March 2014, regarding pain, movement disorders, stroke, amyotrophic lateral sclerosis, multiple sclerosis, epilepsy...

  10. Mind the hand

    DEFF Research Database (Denmark)

    Davidsen, Jacob; Christiansen, Ellen Tove

    2014-01-01

    , to construct and problem solve, and to show and imitate. The analyses show how a space emerges from the interaction between the children and the touchscreen, and how their hand movements reveal intelligence-as-action. Three situations with three different pairs were analysed to explore how children use......Apart from touching the screen, what is the role of the hands for children collaborating around touchscreens? Based on embodied and multimodal interaction analysis of 8- and 9-year old pairs collaborating around touchscreens, we conclude that children use their hands to constrain and control access...... their hands in activities around touchscreens, focusing in particular on how they collaborate. The analysis presented here is part of a research study on the use of touchscreens in children’s embodied and multimodal collaborative learning activities in their everyday classrooms. The general aim of the study...

  11. Repetition in Waiting for Godot

    Institute of Scientific and Technical Information of China (English)

    李想; 魏妍

    2015-01-01

    Waiting for Godot is one of the most famous plays written by Samuel Barclay Beckett, and also is the founding work of“Theatre of the Absurd”. In the drama, repetitive phenomena shed light on the whole construction considerably. All the charac-ters were helpless and unthinking. Their dialogues were simple, nonsense and repetitive. Two scenes were cyclical. Repetition was used subtly in order to express the theme of the play, showing mental crisis after depravation of WWII.

  12. Repetitive Transcranial Magnetic Stimulation Improves Handwriting in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Bubblepreet K. Randhawa

    2013-01-01

    Full Text Available Background. Parkinson disease (PD is characterized by hypometric movements resulting from loss of dopaminergic neurons in the substantia nigra. PD leads to decreased activation of the supplementary motor area (SMA; the net result of these changes is a poverty of movement. The present study determined the impact of 5 Hz repetitive transcranial magnetic stimulation (rTMS over the SMA on a fine motor movement, handwriting (writing cursive “l”s, and on cortical excitability, in individuals with PD. Methods. In a cross-over design, ten individuals with PD were randomized to receive either 5 Hz or control stimulation over the SMA. Immediately following brain stimulation right handed writing was assessed. Results. 5 Hz stimulation increased vertical size of handwriting and diminished axial pressure. In addition, 5 Hz rTMS significantly decreased the threshold for excitability in the primary motor cortex. Conclusions. These data suggest that in the short term 5 Hz rTMS benefits functional fine motor task performance, perhaps by altering cortical excitability across a network of brain regions. Further, these data may provide the foundation for a larger investigation of the effects of noninvasive brain stimulation over the SMA in individuals with PD.

  13. Peripheral and central changes combine to induce motor behavioral deficits in a moderate repetition task

    OpenAIRE

    Coq, Jacques-Olivier; Barr, Ann E.; Strata, Fabrizio; Russier, Michael; Kietrys, David M; Merzenich, Michael M.; Byl, Nancy N; Barbe, Mary F

    2009-01-01

    Repetitive motion disorders, such as carpal tunnel syndrome and focal hand dystonia, can be associated with tasks that require prolonged, repetitive behaviors. Previous studies using animal models of repetitive motion have correlated cortical neuroplastic changes or peripheral tissue inflammation with fine motor performance. However, the possibility that both peripheral and central mechanisms coexist with altered motor performance has not been studied. In this study, we investigated the relat...

  14. Understanding maximal repetitions in strings

    CERN Document Server

    Crochemore, Maxime

    2008-01-01

    The cornerstone of any algorithm computing all repetitions in a string of length n in O(n) time is the fact that the number of runs (or maximal repetitions) is O(n). We give a simple proof of this result. As a consequence of our approach, the stronger result concerning the linearity of the sum of exponents of all runs follows easily.

  15. Changes in chemical permeation of disposable latex, nitrile, and vinyl gloves exposed to simulated movement.

    Science.gov (United States)

    Phalen, Robert N; Le, Thi; Wong, Weng Kee

    2014-01-01

    Glove movement can affect chemical permeation of organic compounds through polymer glove products. However, conflicting reports make it difficult to compare the effects of movement on chemical permeation through commonly available glove types. The aim of this study was to evaluate the effect of movement on chemical permeation of an organic solvent through disposable latex, nitrile, and vinyl gloves. Simulated whole-glove permeation testing was conducted using ethyl alcohol and a previously designed permeation test system. With exposure to movement, a significant decrease (p ≤ 0.001) in breakthrough time (BT) was observed for the latex (-23%) and nitrile gloves (-31%). With exposure to movement, only the nitrile glove exhibited a significant increase (p ≤ 0.001) in steady-state permeation rate (+47%) and cumulative permeation at 30 min (+111%). Even though the nitrile glove provided optimum chemical resistance against ethyl alcohol, it was most affected by movement. With exposure to movement, the latex glove was an equivalent option for overall worker protection, because it was less affected by movement and the permeation rate was lower than that of the nitrile glove. In contrast, the vinyl glove was the least affected by movement, but did not provide adequate chemical resistance to ethyl alcohol in comparison with the nitrile and latex gloves. Glove selection should take movement and polymer type into account. Some glove polymer types are less affected by movement, most notably the latex glove in this test. With nitrile gloves, at least a factor of three should be used when attempting to assign a protection factor when repetitive hand motions are anticipated. Ultimately, the latex gloves outperformed nitrile and vinyl in these tests, which evaluated the effect of movement on chemical permeation. Future research should aim to resolve some of the observed discrepancies in test results with latex and vinyl gloves.

  16. Prototype of a mechanical assistance device for the wrists' flexion-extension movement

    Energy Technology Data Exchange (ETDEWEB)

    Politti, Julio C; Puglisi, Lisandro J; Farfan, Fernando D [Departamento de BioingenierIa - FaCEyT - UNT (Argentina)

    2007-11-15

    Using CMU actuators, a Prototype of Mechanical Assistance Device for the Wrist's Flexion Movement (PMA) was developed and probed in a mechanical model, in order to be implemented in a future as a dynamic powered orthosis or as a rehabilitation assistant instrument. Two Mayor Actuators conformed by three CMU actuators arranged in a series configuration, allows to an artificial hand to be placed in four predefined positions: 0{sup 0}, 20{sup 0}, 40{sup 0} and 60{sup 0}. The synchronism and control of the actuators is achieved with the Programmable Control Module (PCM). It is capable to drive up to six CMU actuators, and possess two different modes of execution: a Manual mode and an Exercise mode. In the Manual Mode, the position of the hand responds directly to the commands of the keyboard of the front panel, and in the Exercise mode, the hand realizes a repetitive and programmed movement. The prototype was tested in 100 positions in the Manual Mode and for 225 works cycles in the Exercise Mode. The relative repetition error was less than 5% for both test. This prototype only consumes 4,15W, which makes it possible to be powered by small rechargeable batteries, allowing its use as a portable device.

  17. Ergonomic Evaluation of Biomechanical Hand Function

    OpenAIRE

    Lee, Kyung-Sun; Jung, Myung-Chul

    2014-01-01

    The human hand is a complex structure that performs various functions for activities of daily living and occupations. This paper presents a literature review on the methodologies used to evaluate hand functions from a biomechanics standpoint, including anthropometry, kinematics, kinetics, and electromyography (EMG). Anthropometry describes the dimensions and measurements of the hand. Kinematics includes hand movements and the range of motion of finger joints. Kinetics includes hand models for...

  18. Hand Eczema

    NARCIS (Netherlands)

    Coenraads, Pieter-Jan

    2012-01-01

    A 33-year-old woman presents with redness of the hands and reports the intermittent occurrence of tiny vesicles, scaling, and fissuring, accompanied by itching on the palms, fingers, and dorsal sides of the hands. She has two young children and works as a nurse in a nearby hospital. She has a histor

  19. Perceptual Repetition Blindness Effects

    Science.gov (United States)

    Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    The phenomenon of repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to post-perceptual processes such as memory retrieval and/or reporting biases. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is, indeed, open to such objections. Here we investigate RB using a "single-frame" paradigm introduced by Johnston and Hale (1984) in which memory demands are minimal. Subjects made only a single judgement about whether one masked target word was the same or different than a post-target probe. Confidence ratings permitted use of signal detection methods to assess sensitivity and bias effects. In the critical condition for RB a precue of the post-target word was provided prior to the target stimulus (identity precue), so that the required judgement amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was either an unrelated word or a dummy.

  20. 左右手运动想象脑电模式识别研究%Study of Discrimination between Left and Right Hand Movements Imagery Event-Related EEG Pattern

    Institute of Scientific and Technical Information of China (English)

    刘成; 何可人; 周天彤; 邹凌

    2013-01-01

    Recently, accurate classification of imaginary left and right hand movemetns of EEG is an important issue in brainOcomputer interface (BCD. Based on EEG data of 3 subjects which collected by -American EGI 640 -channel EEG colletion system, firstly, the effective de-noising processing to collected data by the independent component analysis method is carried out. Secondly, discrete wavelet transform method is used to decompose the average power of the channel C3/C4 in left and right hand movements imagery. The reconstructed signal of approximation coefficient A6 on the sixth level is selected to build up feature signal. Finally, to classify the feature signal respectively by Fisher Linear Discriminant Analysis (FL-DA), Support Vector Machines (SVM) and Extreme Learning Machine (ELM) methods. The classification results show that the average classification rate of -ELM is higher than that of FLDA and SVM, which can achieve 92%. The running speed of ELM is also faster than the other two methods.%如何提高左右手运动想象脑电信号的分类率是脑机接口研究领域的一个热点话题.基于美国EGI64导脑电采集系统得到3名健康被试的脑电数据,首先,采用独立成分分析(Independent Component Analysis,ICA)对采集的数据进行去噪处理;然后,利用离散小波变换方法对分解C3/C4处的EEG平均功率信号,选用尺度6上逼近系数A6的重构信号作为脑电特征信号;最后,用Fisher线性判别分析法(Fisher Linear Discriminant Analysis,FLDA)、支持向量机方法(Support Vector Machines,SVM)和极限学习机分类方法(Extreme Learning Machine,ELM)分别对特征信号进行分类.分类结果表明:极限学习机分类方法得出的平均分类率要高于Fisher方法与SVM方法的平均分类率,可以达到92%,而且运行速度也高于另两种分类算法.

  1. Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

    DEFF Research Database (Denmark)

    Bonde, J. P.; Mikkelsen, S.; Andersen, JH

    2005-01-01

    for development of regional pain in repetitive work, stress symptoms would likely be on the causal path. AIMS: To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms. METHODS: In 1994-95, 2033 unskilled workers with continuous repetitive...... work and 813 workers with varied work were enrolled. Measures of repetitiveness and force requirements were quantified using video observations to obtain individual exposure estimates. Stress symptoms were recorded at baseline and after approximately one, two, and three years by the Setterlind Stress...... Profile Inventory. RESULTS: Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up. CONCLUSIONS...

  2. Hand eczema.

    Science.gov (United States)

    Agarwal, Uma Shankar; Besarwal, Raj Kumar; Gupta, Rahul; Agarwal, Puneet; Napalia, Sheetal

    2014-05-01

    Hand eczema is often a chronic, multifactorial disease. It is usually related to occupational or routine household activities. Exact etiology of the disease is difficult to determine. It may become severe enough and disabling to many of patients in course of time. An estimated 2-10% of population is likely to develop hand eczema at some point of time during life. It appears to be the most common occupational skin disease, comprising 9-35% of all occupational diseases and up to 80% or more of all occupational contact dermatitis. So, it becomes important to find the exact etiology and classification of the disease and to use the appropriate preventive and treatment measures. Despite its importance in the dermatological practice, very few Indian studies have been done till date to investigate the epidemiological trends, etiology, and treatment options for hand eczema. In this review, we tried to find the etiology, epidemiology, and available treatment modalities for chronic hand eczema patients.

  3. Case Report: 84 year-old woman with alien hand syndrome [version 1; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Ihtesham Aatif Qureshi

    2016-07-01

    Full Text Available Background: Alien hand syndrome [AHS] is a rare and ill-defined neurological disorder. It produces complex, goal-directed motion of one hand that is involuntarily instigated. This syndrome characteristically arises after brain trauma, brain surgery, stroke or encephalitis. We describe a case of AHS in a patient who had a previous episode of subarachnoid hemorrhage affecting the left frontal lobe and corpus callosum. Case presentation: An 84-year-old woman presented to the emergency department complaining of headaches and several episodes of her left arm moving as if it was groping around trying to grab at her own body. A computed tomography scan of the head demonstrated an acute left superior frontal hemorrhage with compression of the corpus callosum. Transcranial Doppler report showed no significant abnormality in the insonated vessels. After being stabilized for the acute bleed, she was treated with clonazepam 0.5 mgat night for the uncontrolled hand movements. Her movements resolved by her next month follow up. The diagnosis of AHS was made based on her clinical presentation, characterization of the movement and localization correlating with findings in neuroimaging. Conclusion: We document a rare neurologic disorder seen in patients presenting with a history of previous strokes and a typical description of involuntary and unintentional, uncontrolled unilateral arm movements with repetitive grasping. The present case has a combination of frontal and callosal lesions.  These findings appear to support a potential destruction leading to the rare syndrome.

  4. Task-specific rehabilitation of finger-hand function using interactive computer gaming.

    Science.gov (United States)

    Szturm, Tony; Peters, James F; Otto, Chris; Kapadia, Naaz; Desai, Ankur

    2008-11-01

    The present case study assessed the feasibility of using an interactive gaming system, coupled with the manipulation of common objects, as a form of repetitive, task-specific movement therapy. Three adults with moderate chronic motor impairments of the fingers and hand participated: one 36-year-old man with an incomplete cervical spinal cord injury, one 60-year-old man with a left cortical cerebro-vascular accident, and one 38-year-old woman with left hemiplegic cerebral palsy. Each subject received an intervention of 15 one-hour sessions, which consisted solely of interactive exercise gaming using a diverse range of objects. The objects provided graded and challenging training levels, which emulated the functional properties of objects used in daily life. This in turn produced positive effects on the recovery of active finger range of motion and hand function.

  5. Natural control capabilities of robotic hands by hand amputated subjects.

    Science.gov (United States)

    Atzori, Manfredo; Gijsberts, Arjan; Caputo, Barbara; Muller, Henning

    2014-01-01

    People with transradial hand amputations who own a myoelectric prosthesis currently have some control capabilities via sEMG. However, the control systems are still limited and not natural. The Ninapro project is aiming at helping the scientific community to overcome these limits through the creation of publicly available electromyography data sources to develop and test machine learning algorithms. In this paper we describe the movement classification results gained from three subjects with an homogeneous level of amputation, and we compare them with the results of 40 intact subjects. The number of considered subjects can seem small at first sight, but it is not considering the literature of the field (which has to face the difficulty of recruiting trans-radial hand amputated subjects). The classification is performed with four different classifiers and the obtained balanced classification rates are up to 58.6% on 50 movements, which is an excellent result compared to the current literature. Successively, for each subject we find a subset of up to 9 highly independent movements, (defined as movements that can be distinguished with more than 90% accuracy), which is a deeply innovative step in literature. The natural control of a robotic hand in so many movements could lead to an immediate progress in robotic hand prosthetics and it could deeply change the quality of life of amputated subjects.

  6. Temporal strategy and performance during a fatiguing short-cycle repetitive task

    NARCIS (Netherlands)

    Bosch, T.; Mathiassen, S.E.; Hallman, D.; Looze, M.P. de; Lyskov, E.; Visser, B.; Dieën, J.H. van

    2012-01-01

    This study investigated temporal changes in movement strategy and performance during fatiguing short-cycle work. Eighteen participants performed six 7-min work blocks with repetitive reaching movements at 0.5 Hz, each followed by a 5.5-min rest break for a total duration of 1 h. Electromyography (EM

  7. Too Much of a Good Thing: Prevention of Computer-Related Repetitive Strain Injuries among Children.

    Science.gov (United States)

    Linden, Paul

    1998-01-01

    Examines computer use and repetitive strain injury (RSI) among children and young adults, emphasizing body-awareness training that teaches people to notice and feel body components; understand principles of relaxation, balance, and movement efficiency; and use economical and strain-free ways of accomplishing movements. Outlines elements of safety…

  8. Brain-Computer Link Restores Some Movement to Quadraplegic Man

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_164322.html Brain-Computer Link Restores Some Movement to Quadraplegic Man 8 ... for hand movement. This step created a "brain-computer interface" that was able to interpret which movements ...

  9. Ergonomic Evaluation of Biomechanical Hand Function

    Directory of Open Access Journals (Sweden)

    Kyung-Sun Lee

    2015-03-01

    Full Text Available The human hand is a complex structure that performs various functions for activities of daily living and occupations. This paper presents a literature review on the methodologies used to evaluate hand functions from a biomechanics standpoint, including anthropometry, kinematics, kinetics, and electromyography (EMG. Anthropometry describes the dimensions and measurements of the hand. Kinematics includes hand movements and the range of motion of finger joints. Kinetics includes hand models for tendon and joint force analysis. EMG is used on hand muscles associated with hand functions and with signal-processing technology.

  10. Chronic stroke survivors achieve comparable outcomes following virtual task specific repetitive training guided by a wearable robotic orthosis (UL-EXO7) and actual task specific repetitive training guided by a physical therapist.

    Science.gov (United States)

    Byl, Nancy N; Abrams, Gary M; Pitsch, Erica; Fedulow, Irina; Kim, Hyunchul; Simkins, Matt; Nagarajan, Srikantan; Rosen, Jacob

    2013-01-01

    Survivors post stroke commonly have upper limb impairments. Patients can drive neural reorganization, brain recovery and return of function with task specific repetitive training (TSRT). Fifteen community independent stroke survivors (25-75 years, >6 months post stroke, Upper Limb Fugl Meyer [ULFM] scores 16-39) participated in this randomized feasibility study to compare outcomes of upper limb TSRT guided by a robotic orthosis (bilateral or unilateral) or a physical therapist. After 6 weeks of training (18 h), across all subjects, there were significant improvements in depression, flexibility, strength, tone, pain and voluntary movement (ULFM) (p physical therapist significantly reduced arm impairments around the shoulder and elbow without significant gains in fine motor hand control, activities of daily living or independence.

  11. Mirror movements in progressive hemifacial atrophy

    Science.gov (United States)

    Verma, Rajesh; Dixit, Puneet Kumar; Lalla, Rakesh; Singh, Babita

    2015-01-01

    Mirror movements are simultaneous, involuntary, identical movements occurring during contralateral voluntary movements. These movements are considered as soft neurologic signs seen uncommonly in clinical practice. The mirror movements are described in various neurological disorders which include parkinsonism, cranio veretebral junction anamolies, and hemiplegic cerebral palsy. These movements are intriguing and can pose significant disability. However, no such observation regarding mirror movements in progressive hemifacial atrophy have been reported previously. We are reporting a teenage girl suffering from progressive hemifacial atrophy and epilepsy with demonstrable mirror movements in hand. PMID:26019431

  12. Mirror movements in progressive hemifacial atrophy

    Directory of Open Access Journals (Sweden)

    Rajesh Verma

    2015-01-01

    Full Text Available Mirror movements are simultaneous, involuntary, identical movements occurring during contralateral voluntary movements. These movements are considered as soft neurologic signs seen uncommonly in clinical practice. The mirror movements are described in various neurological disorders which include parkinsonism, cranio veretebral junction anamolies, and hemiplegic cerebral palsy. These movements are intriguing and can pose significant disability. However, no such observation regarding mirror movements in progressive hemifacial atrophy have been reported previously. We are reporting a teenage girl suffering from progressive hemifacial atrophy and epilepsy with demonstrable mirror movements in hand.

  13. Brainstem hypoplasia presenting with mirror movement

    Directory of Open Access Journals (Sweden)

    Burcu Ekmekçi

    2015-09-01

    Full Text Available 20 years old female patient, who had operated from congenital syndactyly on her left hand at five age, admitted to neurology policlinic with involuntary movement on her hands. We saw mirror movement (MM when she writing, catching with her left hand. This movement is had low amplitude in the right hand than left. Cervical MRG revealed no abnormality. Brain MRG revealed right middle, inferior cerebellary peduncle, olive and pyramid hypoplasia. Mirror movement shows homolog muscle activity which simulating contralateral movement, during a spesific task. This movement is seen usually upper extremity especially in the hand. Corticospinal tract dysfunction is often considered in the pathogenesis. MM may present as part of cervico medullary junction abnormality, cerebral palsy, cerebrovasculary disease, Parkinson disease. We wanted to discuss the patogenesis of MM in our patient with syndactyly and MRG abnormality.

  14. Eye–Hand Coordination Skills in Children with and without Amblyopia

    Science.gov (United States)

    Suttle, Catherine M.; Melmoth, Dean R.; Finlay, Alison L.; Sloper, John J.

    2011-01-01

    Purpose. To investigate whether binocular information provides benefits for programming and guidance of reach-to-grasp movements in normal children and whether these eye–hand coordination skills are impaired in children with amblyopia and abnormal binocularity. Methods. Reach-to-grasp performance of the preferred hand in binocular versus monocular (dominant or nondominant eye occluded) conditions to different objects (two sizes, three locations, and two to three repetitions) was quantified by using a 3D motion-capture system. The participants were 36 children (age, 5–11 years) and 11 adults who were normally sighted and 21 children (age, 4–8 years) who had strabismus and/or anisometropia. Movement kinematics and error rates were compared for each viewing condition within and between subject groups. Results. The youngest control subjects used a mainly programmed (ballistic) strategy and collided with the objects more often when viewing with only one eye, while older children progressively incorporated visual feedback to guide their reach and, eventually, their grasp, resulting in binocular advantages for both movement components resembling those of adult performance. Amblyopic children were the worst performers under all viewing conditions, even when using the dominant eye. They spent almost twice as long in the final approach to the objects and made many (1.5–3 times) more errors in reach direction and grip positioning than their normal counterparts, these impairments being most marked in those with the poorest binocularity, regardless of the severity or cause of their amblyopia. Conclusions. The importance of binocular vision for eye–hand coordination normally increases with age and use of online movement guidance. Restoring binocularity in children with amblyopia may improve their poor hand action control. PMID:21212188

  15. Compact Dexterous Robotic Hand

    Science.gov (United States)

    Lovchik, Christopher Scott (Inventor); Diftler, Myron A. (Inventor)

    2001-01-01

    A compact robotic hand includes a palm housing, a wrist section, and a forearm section. The palm housing supports a plurality of fingers and one or more movable palm members that cooperate with the fingers to grasp and/or release an object. Each flexible finger comprises a plurality of hingedly connected segments, including a proximal segment pivotally connected to the palm housing. The proximal finger segment includes at least one groove defining first and second cam surfaces for engagement with a cable. A plurality of lead screw assemblies each carried by the palm housing are supplied with power from a flexible shaft rotated by an actuator and output linear motion to a cable move a finger. The cable is secured within a respective groove and enables each finger to move between an opened and closed position. A decoupling assembly pivotally connected to a proximal finger segment enables a cable connected thereto to control movement of an intermediate and distal finger segment independent of movement of the proximal finger segment. The dexterous robotic hand closely resembles the function of a human hand yet is light weight and capable of grasping both heavy and light objects with a high degree of precision.

  16. Scan patterns when viewing natural scenes: Emotion, complexity, and repetition

    OpenAIRE

    Bradley, Margaret M.; Houbova, Petra; Miccoli,Laura; Costa, Vincent D.; Lang, Peter J.

    2011-01-01

    Eye movements were monitored during picture viewing and effects of hedonic content, perceptual composition, and repetition on scanning assessed. In Experiment 1, emotional and neutral pictures that were figure-ground compositions or more complex scenes were presented for a 6 s free viewing period. Viewing emotional pictures or complex scenes prompted more fixations and broader scanning of the visual array, compared to neutral pictures or simple figure-ground compositions. Effects of emotion a...

  17. [Hand infections].

    Science.gov (United States)

    Schiele, Philippe; Le Nen, Dominique

    2013-11-01

    Superficial and deep hand infections are frequent in general medical practice. Clinical examination is a crucial step for an adapted provided care. Most of the time, surgery is the only way to heal infections. However, in some cases (like bites), empiric antibiotherapy is first indicated to limit infection. Staphyloccocus aureus as well as Group Beta Streptococcus are the most frequently pathogenes associated with hand infections. Methicillin resistant S. Aureus must always be considered in the diagnoses. Whatever treatment is provided, clinical assessement must be repeated within two days. An early adaquated treatment prevent functional complications and in some cases death of the patients.

  18. Curious Repetitions in Magnetars

    Science.gov (United States)

    Archibald, Robert

    2016-07-01

    Magnetars, the slowly spinning branch of the pulsar family with extremely high inferred dipole magnetic fields, often display bizarre spin behaviour rarely seen in their more typical rotation-powered cousins. In this talk, I will tell a tale of two magnetars, 1E 1048.1-5937 and 4U 0142+61 -- both of which seem to be repeating themselves. 1E 1048.1-5937 has, three times, shown flux increases of a factor of ~3 which which decayed over hundreds of days, followed months later by unique order of magnitude torque oscillations. 4U 0142+61, on the other hand, has displayed only short-term, i.e. minutes long, flux increases. In 2006, and now again in 2014, 4U 0142+61 has had typical 1E-7 Hz spin-up glitches which then over-recover on a timescale of weeks, leading to a net spin-down event associated with these short-term flux increases. Both of these sources seem to display a coupling between their X-ray flux and spin-down, but at vastly different timescales. By comparing these repeating events, we will try to shed some new light on the physics driving these extreme objects.

  19. Autism and exergaming: effects on repetitive behaviors and cognition

    Directory of Open Access Journals (Sweden)

    Anderson-Hanley C

    2011-09-01

    Full Text Available Cay Anderson-Hanley, Kimberly Tureck, Robyn L Schneiderman Department of Psychology, Union College, Schenectady, NY, USA Abstract: Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR; in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum. Keywords: autism, repetitive behaviors, exergaming, exercise, executive function

  20. Repetition in English Political Public Speaking

    Institute of Scientific and Technical Information of China (English)

    李红梅

    2010-01-01

    Repetition is frequently used in English political public speaking to make it easy to be remembered and powerful to move the feelings of the public. This paper is intended to analyze the functions of repetition and different levels of repetition to highlight the significance of repetition in English political public speaking and the ability of using it in practice.

  1. Hand eczema

    Directory of Open Access Journals (Sweden)

    Uma Shankar Agarwal

    2014-01-01

    Full Text Available Hand eczema is often a chronic, multifactorial disease. It is usually related to occupational or routine household activities. Exact etiology of the disease is difficult to determine. It may become severe enough and disabling to many of patients in course of time. An estimated 2-10% of population is likely to develop hand eczema at some point of time during life. It appears to be the most common occupational skin disease, comprising 9-35% of all occupational diseases and up to 80% or more of all occupational contact dermatitis. So, it becomes important to find the exact etiology and classification of the disease and to use the appropriate preventive and treatment measures. Despite its importance in the dermatological practice, very few Indian studies have been done till date to investigate the epidemiological trends, etiology, and treatment options for hand eczema. In this review, we tried to find the etiology, epidemiology, and available treatment modalities for chronic hand eczema patients.

  2. Hand Osteoblastoma

    Directory of Open Access Journals (Sweden)

    M. Farzan

    2006-06-01

    Full Text Available Background and Aim: Osteoblastoma is one of the rarest primary bone tumors. Although, small bones of the hands and feet are the third most common location for this tumor, the hand involvement is very rare and few case observations were published in the English-language literature. Materials and Methods: In this study, we report five cases of benign osteoblastoma of the hand, 3 in metacarpals and two in phalanxes. The clinical feature is not specific. The severe nocturnal, salicylate-responsive pain is not present in patients with osteoblastoma. The pain is dull, persistent and less localized. The clinical course is usually long and there is often symptoms for months before medical attention are sought. Swelling is a more persistent finding in osteoblastoma of the hand that we found in all of our patients. The radiologic findings are indistinctive, so preoperative diagnosis based on X-ray appearance is difficult. In all of our 5 cases, we fail to consider osteoblastoma as primary diagnosis. Pathologically, osteoblastoma consisting of a well-vascularized connective tissue stroma in which there is active production of osteoid and primitive woven bone. Treatment depends on the stage and localization of the tumor. Curettage and bone grafting is sufficient in stage 1 or stage 2, but in stage 3 wide resection is necessary for prevention of recurrence. Osteosarcoma is the most important differential diagnosis that may lead to inappropriate operation.

  3. Hand eczema

    DEFF Research Database (Denmark)

    Ibler, K.S.; Jemec, G.B.E.; Flyvholm, M.-A.

    2012-01-01

    /materials/methods. A survey of 3181 healthcare workers was performed. Data were analysed with logistic regression. Data on sick leave and notification to the authorities were obtained. Results. The response rate was 71% (2274 of 3181). The 1-year prevalence of hand eczema was 21%, and was positively associated with atopic...

  4. Magic Hands

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    THE two most amazing things on the planet may well be the human brain and human hands. When they work together, the results can be enchanting. At an international folk art fair held recently in Beijing, artisans and masters from Japan, India, Switzerland, Peru, South

  5. A little elastic for a better performance: kinesiotaping of the motor effector modulates neural mechanisms for rhythmic movements

    Science.gov (United States)

    Bravi, Riccardo; Quarta, Eros; Cohen, Erez J.; Gottard, Anna; Minciacchi, Diego

    2014-01-01

    A rhythmic motor performance is brought about by an integration of timing information with movements. Investigations on the millisecond time scale distinguish two forms of time control, event-based timing and emergent timing. While event-based timing asserts the existence of a central internal timekeeper for the control of repetitive movements, the emergent timing perspective claims that timing emerges from dynamic control of nontemporal movements parameters. We have recently demonstrated that the precision of an isochronous performance, defined as performance of repeated movements having a uniform duration, was insensible to auditory stimuli of various characteristics (Bravi et al., 2014). Such finding has led us to investigate whether the application of an elastic therapeutic tape (Kinesio® Tex taping; KTT) used for treating athletic injuries and a variety of physical disorders, is able to reduce the timing variability of repetitive rhythmic movement. Young healthy subjects, tested with and without KTT, have participated in sessions in which sets of repeated isochronous wrist's flexion-extensions (IWFEs) were performed under various auditory conditions and during their recall. Kinematics was recorded and temporal parameters were extracted and analyzed. Our results show that the application of KTT decreases the variability of rhythmic movements by a 2-fold effect: on the one hand KTT provides extra proprioceptive information activating cutaneous mechanoreceptors, on the other KTT biases toward the emergent timing thus modulating the processes for rhythmic movements. Therefore, KTT appears able to render movements less audio dependent by relieving, at least partially, the central structures from time control and making available more resources for an augmented performance. PMID:25309355

  6. A little elastic for a better performance: kinesiotaping of the motor effector modulates neural mechanisms for rhythmic movements

    Directory of Open Access Journals (Sweden)

    Riccardo eBravi

    2014-09-01

    Full Text Available A rhythmic motor performance is brought about by an integration of timing information with movements. Investigations on the millisecond time scale distinguish two forms of time control, event-based timing and emergent timing. While event-based timing asserts the existence of a central internal timekeeper for the control of repetitive movements, the emergent timing perspective claims that timing emerges from dynamic control of nontemporal movements parameters. We have recently demonstrated that the precision of an isochronous performance, defined as performance of repeated movements having a uniform duration, was insensible to auditory stimuli of various characteristics (Bravi et al., 2014. Such finding has led us to investigate whether the application of an elastic therapeutic tape (Kinesio® Tex taping; KTT used for treating athletic injuries and a variety of physical disorders, is able to reduce the timing variability of repetitive rhythmic movement. Young healthy subjects, tested with and without KTT, have participated in sessions in which sets of repeated isochronous wrist's flexion-extensions (IWFEs were performed under various auditory conditions and during their recall. Kinematics was recorded and temporal parameters were extracted and analyzed. Our results show that the application of KTT decreases the variability of rhythmic movements by a twofold effect: on the one hand KTT provides extra proprioceptive information activating cutaneous mechanoreceptors, on the other KTT biases toward the emergent timing thus modulating the processes for rhythmic movements. Therefore, KTT appears able to render movements less audio dependent by relieving, at least partially, the central structures from time control and making available more resources for an augmented performance.

  7. A little elastic for a better performance: kinesiotaping of the motor effector modulates neural mechanisms for rhythmic movements.

    Science.gov (United States)

    Bravi, Riccardo; Quarta, Eros; Cohen, Erez J; Gottard, Anna; Minciacchi, Diego

    2014-01-01

    A rhythmic motor performance is brought about by an integration of timing information with movements. Investigations on the millisecond time scale distinguish two forms of time control, event-based timing and emergent timing. While event-based timing asserts the existence of a central internal timekeeper for the control of repetitive movements, the emergent timing perspective claims that timing emerges from dynamic control of nontemporal movements parameters. We have recently demonstrated that the precision of an isochronous performance, defined as performance of repeated movements having a uniform duration, was insensible to auditory stimuli of various characteristics (Bravi et al., 2014). Such finding has led us to investigate whether the application of an elastic therapeutic tape (Kinesio® Tex taping; KTT) used for treating athletic injuries and a variety of physical disorders, is able to reduce the timing variability of repetitive rhythmic movement. Young healthy subjects, tested with and without KTT, have participated in sessions in which sets of repeated isochronous wrist's flexion-extensions (IWFEs) were performed under various auditory conditions and during their recall. Kinematics was recorded and temporal parameters were extracted and analyzed. Our results show that the application of KTT decreases the variability of rhythmic movements by a 2-fold effect: on the one hand KTT provides extra proprioceptive information activating cutaneous mechanoreceptors, on the other KTT biases toward the emergent timing thus modulating the processes for rhythmic movements. Therefore, KTT appears able to render movements less audio dependent by relieving, at least partially, the central structures from time control and making available more resources for an augmented performance.

  8. Quantifying repetitive speech in autism spectrum disorders and language impairment.

    Science.gov (United States)

    van Santen, Jan P H; Sproat, Richard W; Hill, Alison Presmanes

    2013-10-01

    We report on an automatic technique for quantifying two types of repetitive speech: repetitions of what the child says him/herself (self-repeats) and of what is uttered by an interlocutor (echolalia). We apply this technique to a sample of 111 children between the ages of four and eight: 42 typically developing children (TD), 19 children with specific language impairment (SLI), 25 children with autism spectrum disorders (ASD) plus language impairment (ALI), and 25 children with ASD with normal, non-impaired language (ALN). The results indicate robust differences in echolalia between the TD and ASD groups as a whole (ALN + ALI), and between TD and ALN children. There were no significant differences between ALI and SLI children for echolalia or self-repetitions. The results confirm previous findings that children with ASD repeat the language of others more than other populations of children. On the other hand, self-repetition does not appear to be significantly more frequent in ASD, nor does it matter whether the child's echolalia occurred within one (immediate) or two turns (near-immediate) of the adult's original utterance. Furthermore, non-significant differences between ALN and SLI, between TD and SLI, and between ALI and TD are suggestive that echolalia may not be specific to ALN or to ASD in general. One important innovation of this work is an objective fully automatic technique for assessing the amount of repetition in a transcript of a child's utterances.

  9. Alien Hand Syndrome.

    Science.gov (United States)

    Hassan, Anhar; Josephs, Keith A

    2016-08-01

    Alien hand syndrome (AHS) is a rare disorder of involuntary limb movement together with a sense of loss of limb ownership. It most commonly affects the hand, but can occur in the leg. The anterior (frontal, callosal) and posterior variants are recognized, with distinguishing clinical features and anatomical lesions. Initial descriptions were attributed to stroke and neurosurgical operations, but neurodegenerative causes are now recognized as most common. Structural and functional imaging and clinical studies have implicated the supplementary motor area, pre-supplementary motor area, and their network connections in the frontal variant of AHS, and the inferior parietal lobule and connections in the posterior variant. Several theories are proposed to explain the pathophysiology. Herein, we review the literature to update advances in the understanding of the classification, pathophysiology, etiology, and treatment of AHS.

  10. Varianish: Jamming with Pattern Repetition

    Directory of Open Access Journals (Sweden)

    Jort Band

    2014-10-01

    Full Text Available In music, patterns and pattern repetition are often regarded as a machine-like task, indeed often delegated to drum Machines and sequencers. Nevertheless, human players add subtle differences and variations to repeated patterns that are musically interesting and often unique. Especially when looking at minimal music, pattern repetitions create hypnotic effects and the human mind blends out the actual pattern to focus on variation and tiny differences over time. Varianish is a musical instrument that aims at turning this phenomenon into a new musical experience for musician and audience: Musical pattern repetitions are found in live music and Varianish generates additional (musical output accordingly that adds substantially to the overall musical expression. Apart from the theory behind the pattern finding and matching and the conceptual design, a demonstrator implementation of Varianish is presented and evaluated.

  11. Efficient human hand kinematics for manipulation tasks

    OpenAIRE

    Cobos Guzmán, Salvador; Ferre Perez, Manuel; Sanchez-Uran Gonzalez, Miguel Angel; Ortego la Moneda, Javier; Peña, César

    2008-01-01

    This work is focused on obtaining efficient human hand models that are suitable for manipulation tasks. A 24 DoF kinematic model of the human hand is defined to realistic movements. This model is based on the human skeleton. Dynamic and Static constraints have been included in order to improve the movement realism. Two simplified hand models with 9 and 6 DoF have been developed according to the constraints predefined. These simplified models involve some errors in reconstructing the hand post...

  12. REPETITIVE CLUSTER-TILTED ALGEBRAS

    Institute of Scientific and Technical Information of China (English)

    Zhang Shunhua; Zhang Yuehui

    2012-01-01

    Let H be a finite-dimensional hereditary algebra over an algebraically closed field k and CFm be the repetitive cluster category of H with m ≥ 1.We investigate the properties of cluster tilting objects in CFm and the structure of repetitive clustertilted algebras.Moreover,we generalize Theorem 4.2 in [12](Buan A,Marsh R,Reiten I.Cluster-tilted algebra,Trans.Amer.Math.Soc.,359(1)(2007),323-332.) to the situation of CFm,and prove that the tilting graph KCFm of CFm is connected.

  13. 10 Hz rTMS over right parietal cortex alters sense of agency during self-controlled movements

    Science.gov (United States)

    Ritterband-Rosenbaum, Anina; Karabanov, Anke N.; Christensen, Mark S.; Nielsen, Jens Bo

    2014-01-01

    A large body of fMRI and lesion-literature has provided evidence that the Inferior Parietal Cortex (IPC) is important for sensorimotor integration and sense of agency (SoA). We used repetitive transcranial magnetic stimulation (rTMS) to explore the role of the IPC during a validated SoA detection task. 12 healthy, right-handed adults were included. The effects of rTMS on subjects' SoA during self-controlled movements were explored. The experiment consisted of 1/3 self-controlled movements and 2/3 computer manipulated movements that introduced uncertainty as to whether the subjects were agents of an observed movement. Subjects completed three sessions, in which subjects received online rTMS over the right IPC (active condition), over the vertex (CZ) (sham condition) or no TMS but a sound-matched control. We found that rTMS over right IPC significantly altered SoA of the non-perturbed movements. Following IPC stimulation subjects were more likely to experience self-controlled movements as being externally perturbed compared to the control site (P = 0.002) and the stimulation-free control (P = 0.042). The data support the importance of IPC activation during sensorimotor comparison in order to correctly determine the agent of movements. PMID:25009489

  14. 10 Hz rTMS over right parietal cortex alters sense of agency during self-generated movements

    Directory of Open Access Journals (Sweden)

    Anina eRitterband-Rosenbaum

    2014-06-01

    Full Text Available A large body of fMRI and lesion-literature has provided evidence that the Inferior Parietal Cortex (IPC is important for sensorimotor integration and sense of agency (SoA. We used repetitive transcranial magnetic stimulation (rTMS to explore the role of the IPC during a validated SoA detection task. 12 healthy, right-handed adults were included. The effects of rTMS on subjects’ SoA during self-generated movements were explored. The experiment consisted of 1/3 self-generated movements and 2/3 computer manipulated movements that introduced uncertainty as to whether the subjects were agents of an observed movement. Subjects completed three sessions, in which subjects received online rTMS over the right IPC (active condition, over the vertex (CZ (sham condition or no TMS but a sound-matched control. We found that rTMS over right IPC significantly altered SoA of the non-perturbed movements. Following IPC stimulation subjects were more likely to experience self-generated movements as being externally perturbed compared to the control site (P=0.002 and the stimulation-free control (P=0.042. The data support the importance of IPC activation during sensorimotor comparison in order to correctly determine the agent of movements.

  15. Relationship between postural control and restricted, repetitive behaviors in autism spectrum disorders

    OpenAIRE

    Krestin eRadonovich; Fournier, Kimberly A.; Christopher J. Hass

    2013-01-01

    Restricted, repetitive behaviors (RRBs) are one of the core diagnostic criteria of autism spectrum disorders (ASD), and include simple repetitive motor behaviors and more complex cognitive behaviors, such as compulsions and restricted interests. In addition to the core symptoms, impaired movement is often observed in ASD. Research suggests that the postural system in individuals with ASD is immature and may never reach adult levels. RRBs have been related to postural sway in individuals with...

  16. Repetitive elements in parasitic protozoa

    Directory of Open Access Journals (Sweden)

    Clayton Christine

    2010-05-01

    Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

  17. Movement Strategies in a Haptic Search Task

    NARCIS (Netherlands)

    van Polanen, V.; Bergmann Tiest, W.M.; Kappers, A.M.L.

    2011-01-01

    Movement strategies were investigated in a haptic search task where participants indicated whether a target was present among a varying number of items. Hand movements were classified according to two criteria into three movement types. Results indicated that an easy search was performed with a para

  18. Action planning with two-handed tools.

    Science.gov (United States)

    Herwig, Arvid; Massen, Cristina

    2009-09-01

    In tool use, the intended external goals have to be transformed into bodily movements by taking into account the target-to-movement mapping implemented by the tool. In bimanual tool use, this mapping may depend on the part of the tool that is operated and the effector used (e.g. the left and right hand at the handle bar moving in opposite directions in order to generate the same bicycle movement). In our study, we investigated whether participants represent the behaviour of the tool or only the effector-specific mapping when using two-handed tools. In three experiments, participants touched target locations with a two-jointed lever, using either the left or the right hand. In one condition, the joint of the lever was constant and switching between hands was associated with switching the target-to-movement-mapping, whereas in another condition, switching between hands was associated with switching the joint, but the target-to-movement-mapping remained constant. Results indicate pronounced costs of switching hands in the condition with constant joint, whereas they were smaller with constant target-to-movement mapping. These results suggest that participants have tool-independent representations of the effector-specific mappings.

  19. Repetition suppression and repetition priming are processing outcomes.

    Science.gov (United States)

    Wig, Gagan S

    2012-01-01

    Abstract There is considerable evidence that repetition suppression (RS) is a cortical signature of previous exposure to the environment. In many instances RS in specific brain regions is accompanied by improvements in specific behavioral measures; both observations are outcomes of repeated processing. In understanding the mechanism by which brain changes give rise to behavioral changes, it is important to consider what aspect of the environment a given brain area or set of areas processes, and how this might be expressed behaviorally.

  20. Autism and exergaming: effects on repetitive behaviors and cognition.

    Science.gov (United States)

    Anderson-Hanley, Cay; Tureck, Kimberly; Schneiderman, Robyn L

    2011-01-01

    Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR); in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum.

  1. Cohesive Function of Lexical Repetition in Text

    Institute of Scientific and Technical Information of China (English)

    张莉; 卢沛沛

    2013-01-01

    Lexical repetition is the most direct form of lexical cohesion,which is the central device for making texts hang together. Although repetition is the most direct way to emphasize,it performs the cohesive effect more apparently.

  2. Hand controller commonality evaluation process

    Science.gov (United States)

    Stuart, Mark A.; Bierschwale, John M.; Wilmington, Robert P.; Adam, Susan C.; Diaz, Manuel F.; Jensen, Dean G.

    1993-01-01

    Hand controller selection for NASA's Orbiter and Space Station Freedom is an important area of human-telerobot interface design and evaluation. These input devices will control remotely operated systems that include large crane-like manipulators (e.g., Remote Manipulator System or RMS), smaller, more dexterous manipulators (e.g., Flight Telerobotic Servicer or FTS), and free flyers (e.g., Orbital Maneuvering Vehicle or OMV). Candidate hand controller configurations for these systems vary in many ways: shape, size, number of degrees-of-freedom (DOF), operating modes, provision of force reflection, range of movement, and 'naturalness' of use. Unresolved design implementation issues remain, including such topics as how the current Orbiter RMS rotational and translational rate hand controllers compare with the proposed Space Station Freedom hand controllers, the advantages that position hand controllers offer for these applications, and whether separate hand controller configurations are required for each application. Since previous studies contain little empirical hand controller task performance data, a controlled study is needed that tests Space Station Freedom candidate hand controllers during representative tasks. This study also needs to include anthropometric and biomechanical considerations.

  3. Executed and Imagined Bimanual Movements: A Study across Different Ages

    Science.gov (United States)

    Piedimonte, Alessandro; Garbarini, Francesca; Rabuffetti, Marco; Pia, Lorenzo; Berti, Anna

    2014-01-01

    Movements with both hands are essential to our everyday life, and it has been shown that performing asymmetric bimanual movements produces an interference effect between hands. There have been many studies--using varying methods--investigating the development of bimanual movements that show that this skill continues to evolve during childhood and…

  4. Modified Constraint-Induced Movement Therapy combined with Bimanual Training (mCIMT-BiT) in children with unilateral spastic cerebral palsy: how are improvements in arm-hand use established?

    NARCIS (Netherlands)

    Aarts, P.B.M.; Jongerius, P.H.; Geerdink, Y.A.; Limbeek, J. van; Geurts, A.C.H.

    2011-01-01

    A recent randomized controlled trial indicated that modified Constraint-Induced Movement Therapy followed by Bimanual Training (mCIMT-BiT) is an effective intervention to improve spontaneous use of the affected upper limb in children with unilateral spastic cerebral palsy (CP). The present study aim

  5. Modified Constraint-Induced Movement Therapy Combined with Bimanual Training (mCIMT-BiT) in Children with Unilateral Spastic Cerebral Palsy: How Are Improvements in Arm-Hand Use Established?

    Science.gov (United States)

    Aarts, Pauline B.; Jongerius, Peter H.; Geerdink, Yvonne A.; van Limbeek, Jacques; Geurts, Alexander C.

    2011-01-01

    A recent randomized controlled trial indicated that modified Constraint-Induced Movement Therapy followed by Bimanual Training (mCIMT-BiT) is an effective intervention to improve spontaneous use of the affected upper limb in children with unilateral spastic cerebral palsy (CP). The present study aimed to investigate how the above-mentioned…

  6. The effect of low frequency repetitive transcranial magnetic stimulation on acute cerebral infarction patients movement function recovery%低频重复经颅磁刺激对急性脑梗死患者运动功能恢复的影响

    Institute of Scientific and Technical Information of China (English)

    宁耀超; 孙辉

    2013-01-01

    目的 探讨低频重复经颅磁刺激(rTMS)对急性脑梗死患者运动功能恢复的影响,以期能为低频rTMS治疗急性脑梗死的深入研究及临床应用提供一定参考依据.方法 选取60例急性脑梗死伴单侧肢体运动功能障碍患者,按随机数字表法分为低频rTMS组与对照组,每组30例,两组均给予常规药物治疗及康复训练,低频rTMS组在以上治疗基础上加用低频rTMS治疗10d,观察两组患者治疗前、治疗后10d、治疗后40d时美国国立卫生院神经功能缺损评分(NIHSS)、Fugl-Meyer运动量表(FMA)评分及Barthel指数(BI)评分变化.结果 低频rTMS组治疗前NIHSS、BI评分和FMA评分分别为(16.44±3.29)、(36.69±5.97)、(31.06±7.43)分,对照组分别为(16.38±4.01)、(35.98±6.41)、(30.87±8.56)分,两组比较差异无统计学意义(P>0.05).低频rTMS组治疗后10d NIHSS评分、BI评分和FMA评分分别为(8.13±2.18)、(56.04±5.21)、(48.42±7.73)分,对照组分别为(11.23±1.97)、(50.12±4.88)、(42.12±8.61)分;低频rTMS组治疗后40d NIHSS、BI评分和FMA评分分别为(3.11±0.53)、(73.29±5.34)、(61.63±8.36)分,对照组分别为(5.62±0.98)、(63.96±4.46)、(52.45±7.61)分.两组治疗后10、40d NIHSS均较治疗前明显下降,BI及FMA评分均较治疗前明显升高,差异有统计学意义(P<0.05);低频rTMS组治疗后10、40d NIHSS、BI评分和FMA评分与对照组比较差异均有统计学意义(P<0.05).结论 低频rTMS对急性脑梗死患者运动功能恢复有明显的促进作用.%Objective To investigate low frequency repetitive transcranial magnetic stimulation (rTMS) on acute cerebral infarction (ACI) patients movement function recovery,in order to provide certain reference basis about the further research on low frequency rTMS treatment ACI and clinical application.Methods Sixty patients of ACI with unilateral limb movement function disorder were divided into low frequency rTMS group and control group by table of

  7. Scan patterns when viewing natural scenes: emotion, complexity, and repetition.

    Science.gov (United States)

    Bradley, Margaret M; Houbova, Petra; Miccoli, Laura; Costa, Vincent D; Lang, Peter J

    2011-11-01

    Eye movements were monitored during picture viewing, and effects of hedonic content, perceptual composition, and repetition on scanning assessed. In Experiment 1, emotional and neutral pictures that were figure-ground compositions or more complex scenes were presented for a 6-s free viewing period. Viewing emotional pictures or complex scenes prompted more fixations and broader scanning of the visual array, compared to neutral pictures or simple figure-ground compositions. Effects of emotion and composition were independent, supporting the hypothesis that these oculomotor indices reflect enhanced information seeking. Experiment 2 tested an orienting hypothesis by repeatedly presenting the same pictures. Although repetition altered specific scan patterns, emotional, compared to neutral, picture viewing continued to prompt oculomotor differences, suggesting that motivationally relevant cues enhance information seeking in appetitive and defensive contexts. Copyright © 2011 Society for Psychophysiological Research.

  8. Plasticity-Inducing TMS Protocols to Investigate Somatosensory Control of Hand Function

    Directory of Open Access Journals (Sweden)

    M. Jacobs

    2012-01-01

    Full Text Available Hand function depends on sensory feedback to direct an appropriate motor response. There is clear evidence that somatosensory cortices modulate motor behaviour and physiology within primary motor cortex. However, this information is mainly from research in animals and the bridge to human hand control is needed. Emerging evidence in humans supports the notion that somatosensory cortices modulate motor behaviour, physiology and sensory perception. Transcranial magnetic stimulation (TMS allows for the investigation of primary and higher-order somatosensory cortices and their role in control of hand movement in humans. This review provides a summary of several TMS protocols in the investigation of hand control via the somatosensory cortices. TMS plasticity inducing protocols reviewed include paired associative stimulation, repetitive TMS, theta-burst stimulation as well as other techniques that aim to modulate cortical excitability in sensorimotor cortices. Although the discussed techniques may modulate cortical excitability, careful consideration of experimental design is needed to isolate factors that may interfere with desired results of the plasticity-inducing protocol, specifically events that may lead to metaplasticity within the targeted cortex.

  9. Circuit For Control Of Electromechanical Prosthetic Hand

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

    Proposed circuit for control of electromechanical prosthetic hand derives electrical control signals from shoulder movements. Updated, electronic version of prosthesis, that includes two hooklike fingers actuated via cables from shoulder harness. Circuit built around favored shoulder harness, provides more dexterous movement, without incurring complexity of computer-controlled "bionic" or hydraulically actuated devices. Additional harness and potentiometer connected to similar control circuit mounted on other shoulder. Used to control stepping motor rotating hand about prosthetic wrist to one of number of angles consistent with number of digital outputs. Finger-control signals developed by circuit connected to first shoulder harness transmitted to prosthetic hand via sliprings at prosthetic wrist joint.

  10. Investigating repetition and change in musical rhythm by functional MRI.

    Science.gov (United States)

    Danielsen, A; Otnæss, M K; Jensen, J; Williams, S C R; Ostberg, B C

    2014-09-05

    Groove-based rhythm is a basic and much appreciated feature of Western popular music. It is commonly associated with dance, movement and pleasure and is characterized by the repetition of a basic rhythmic pattern. At various points in the musical course, drum breaks occur, representing a change compared to the repeated pattern of the groove. In the present experiment, we investigated the brain response to such drum breaks in a repetitive groove. Participants were scanned with functional magnetic resonance imaging (fMRI) while listening to a previously unheard naturalistic groove with drum breaks at uneven intervals. The rhythmic pattern and the timing of its different parts as performed were the only aspects that changed from the repetitive sections to the breaks. Differences in blood oxygen level-dependent activation were analyzed. In contrast to the repetitive parts, the drum breaks activated the left cerebellum, the right inferior frontal gyrus (RIFG), and the superior temporal gyri (STG) bilaterally. A tapping test using the same stimulus showed an increase in the standard deviation of inter-tap-intervals in the breaks versus the repetitive parts, indicating extra challenges for auditory-motor integration in the drum breaks. Both the RIFG and STG have been associated with structural irregularity and increase in musical-syntactical complexity in several earlier studies, whereas the left cerebellum is known to play a part in timing. Together these areas may be recruited in the breaks due to a prediction error process whereby the internal model is being updated. This concurs with previous research suggesting a network for predictive feed-forward control that comprises the cerebellum and the cortical areas that were activated in the breaks.

  11. A Hands-Free Interface for Controlling Virtual Electric-Powered Wheelchairs

    Directory of Open Access Journals (Sweden)

    Tauseef Gulrez

    2016-03-01

    Full Text Available This paper focuses on how to provide mobility to people with motor impairments with the integration of robotics and wearable computing systems. The burden of learning to control powered mobility devices should not fall entirely on the people with disabilities. Instead, the system should be able to learn the user's movements. This requires learning the degrees of freedom of user movement, and mapping these degrees of freedom onto electric-powered wheelchair (EPW controls. Such mapping cannot be static because in some cases users will eventually improve with practice. Our goal in this paper is to present a hands-free interface (HFI that can be customized to the varying needs of EPW users with appropriate mapping between the users' degrees of freedom and EPW controls. EPW users with different impairment types must learn how to operate a wheelchair with their residual body motions. EPW interfaces are often customized to fit their needs. An HFI utilizes the signals generated by the user's voluntary shoulder and elbow movements and translates them into an EPW control scheme. We examine the correlation of kinematics that occur during moderately paced repetitive elbow and shoulder movements for a range of motion. The output of upper-limb movements (shoulder and elbows was tested on six participants, and compared with an output of a precision position tracking (PPT optical system for validation. We find strong correlations between the HFI signal counts and PPT optical system during different upper-limb movements (ranged from r = 0.86 to 0.94. We also tested the HFI performance in driving the EPW in a virtual reality environment on a spinal-cord-injured (SCI patient. The results showed that the HFI was able to adapt and translate the residual mobility of the SCI patient into efficient control commands within a week's training. The results are encouraging for the development of more efficient HFIs, especially for wheelchair users.

  12. Atypical presentation of NREM arousal parasomnia with repetitive episodes.

    Science.gov (United States)

    Trajanovic, N N; Shapiro, C M; Ong, A

    2007-08-01

    The case report describes a distinct variant of non-REM (Rapid Eye Movement) arousal parasomnia, sleepwalking type, featuring repetitive abrupt arousals, mostly from slow-wave sleep, and various automatisms and semi-purposeful behaviours. The frequency of events and distribution throughout the night presented as a continuous status of parasomnia ('status parasomnicus'). The patient responded well to treatment typically administered for adult NREM parasomnias, and after careful review of the clinical presentation, objective findings and treatment outcome, sleep-related epilepsy was ruled out in favour of parasomnia.

  13. Circuit considerations for repetitive railguns

    Energy Technology Data Exchange (ETDEWEB)

    Honih, E.M.

    1986-01-01

    Railgun electromagnetic launchers have significant military and scientific potential. They provide direct conversion of electrical energy to projectile kinetic energy, and they offer the hope of achieving projectile velocities greatly exceeding the limits of conventional guns. With over 10 km/sec already demonstrated, railguns are attracting attention for tactical and strategic weapons systems and for scientific equation-of-state research. The full utilization of railguns will require significant improvements in every aspect of system design - projectile, barrel, and power source - to achieve operation on a large scale. This paper will review fundamental aspects of railguns, with emphasis on circuit considerations and repetitive operation.

  14. 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

    mixed-effects models as viable alternatives to conventional analysis frameworks. The model is then combined with a novel factor-analysis model that estimates the low-dimensional subspace within which movements vary when the task demands vary. Our framework enables us to visualize different dimensions......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...... 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....

  15. 原地双手头上抛掷实心球错误动作解析——基于鞭打动作原理%Place Both Hands Head Proves Wrong Action Casting Analytical——Based on the Beat Movement Theory

    Institute of Scientific and Technical Information of China (English)

    李浩然

    2012-01-01

    Both hands head proves is essentially throwing technical movements throwing javelin technique the last part of the action,that is,from "the full bow" to equipment to make moves,belong to the scourge process.Hands head throwing the formation and proves wrong action scourge action correctly or not has the very big relations.Using whipped movement theory analysis proves wrong action of casting,facilitate students to understand.%双手头上抛掷实心球技术动作实质上是投掷标枪技术动作的最后一部分,即从"满弓"到器械出手,属于鞭打用力过程。双手头上抛掷实心球错误动作的产生与鞭打动作正确与否有很大关系。运用鞭打动作原理解析抛掷实心球的错误动作,便于学生理解。

  16. Eventful places in the 2011 movements

    DEFF Research Database (Denmark)

    Risager, Bjarke Skærlund

    as locale, location and sense of place, I show how the 2011 movements re-created the occupied places of Tahrir Square, Zuccotti Park and elsewhere along these three dimensions of place. This re-creation, I suggest, can be grasped as an attempt to transform a hegemonic place, a node in hegemonic structures......Inspired by the Occupy movement, the Egyptian revolutionaries and other of the 2011 social movements, this paper investigates the relationship between social movement and place. Drawing on first-hand accounts from these movements, I argue that the relationship between movement and place...... is dialectical and mutually constitutive: the physical and symbolic characteristics of place influence the formation of the movement and its actions while the latter re-creates the place. This is a corrective to a dominant approach in social movement studies to see movements as a ‘dependent variable...

  17. The effects of subthreshold 1 Hz repetitive TMS on cortico-cortical and interhemispheric coherence

    NARCIS (Netherlands)

    Strens, L.H.; Oliviero, A.; Bloem, B.R.; Gerschlager, W.; Rothwell, J.C.; Brown, P.

    2002-01-01

    OBJECTIVES: Repetitive transcranial magnetic stimulation (rTMS) shows promise as a treatment for various movement and psychiatric disorders. Just how rTMS may have persistent effects on cortical function remains unclear. We hypothesised that it may act by modulating cortico-cortical and interhemisph

  18. Environmental conditions associated with repetitive behavior in a group of African elephants.

    Science.gov (United States)

    Hasenjager, Matthew J; Bergl, Richard A

    2015-01-01

    Repetitive movement patterns are commonly observed in zoo elephants. The extent to which these behaviors constitute a welfare concern varies, as their expression ranges from stereotypies to potentially beneficial anticipatory behaviors. Nevertheless, their occurrence in zoo animals is often viewed negatively. To better identify conditions that prompt their performance, observations were conducted on six African elephants (Loxodonta africana) at the North Carolina Zoo. Individuals spent most of their time engaged in feeding, locomotion, resting, and repetitive behavior. Both generalized estimating equation and zero-inflated negative binomial models were used to identify factors associated with increased rates of repetitive behavior. Time of day in conjunction with location on- or off-exhibit best explained patterns of repetitive behavior. Repetitive behaviors occurred at a lower rate in the morning when on-exhibit, as compared to afternoons on-exhibit or at any time of day off-exhibit. Increased repetitive behavior rates observed on-exhibit in the afternoon prior to the evening transfer and feeding were possibly anticipatory responses towards those events. In contrast, consistently elevated frequencies of repetitive behavior off-exhibit at all times of day could be related to differences in exhibit complexity between off-exhibit and on-exhibit areas, as well as a lack of additional foraging opportunities. Our study contributes valuable information on captive elephant behavior and represents a good example of how behavioral research can be employed to improve management of zoo animals.

  19. Improving Hand Function in Stroke Survivors: A Pilot Study of Contralaterally Controlled Functional Electrical Stimulation in Chronic Hemiplegia

    Science.gov (United States)

    Knutson, Jayme S.; Harley, Mary Y.; Hisel, Terri Z.; Chae, John

    2014-01-01

    Objective To assess the feasibility of a new stroke rehabilitation therapy for the hemiparetic hand. Design Case series. Pre- and post-intervention assessment with 1 and 3 month follow-ups. Setting Clinical research laboratory of a large public hospital. Participants Three subjects with chronic (> 6 mo post-CVA) upper extremity hemiplegia. Intervention Subjects used an electrical stimulator to cause the paretic hand extensor muscles to contract and thereby open the hand. The subjects controlled the intensity of the stimulation, and thus the degree of hand opening, by volitionally opening the unimpaired contralateral hand, which was detected by an instrumented glove. For 6 weeks the subjects used the stimulator to perform active repetitive hand opening exercises 2 hours daily at home and functional tasks 1½ hours twice a week in the laboratory. Outcome Measures Maximum voluntary finger extension, maximum voluntary isometric finger extension moment, finger movement control, and Box and Block score at pre- and post-treatment, and at 1 month and 3 months post-treatment. Results Maximum voluntary finger extension increased from baseline to end-of-treatment and from end-of-treatment to 1 month follow-up in two subjects. Maximum voluntary isometric finger extension moment, finger movement control, and Box and Block score increased from baseline to end-of-treatment and from end-of-treatment to 1 month follow-up in all 3 subjects. The improvements generally declined at 3 months. Conclusions The results suggest a positive effect on motor impairment, meriting further investigation of the intervention. PMID:17398254

  20. Evidence for right-hand feeding biases in a left-handed population.

    Science.gov (United States)

    Flindall, Jason W; Stone, Kayla D; Gonzalez, Claudia L R

    2015-05-01

    We have recently shown that actions with similar kinematic requirements, but different end-state goals may be supported by distinct neural networks. Specifically, we demonstrated that when right-handed individuals reach-to-grasp food items with intent to eat, they produce smaller maximum grip apertures (MGAs) than when they grasp the same item with intent to place it in a location near the mouth. This effect was restricted to right-handed movements; left-handed movements showed no difference between tasks. The current study investigates whether (and to which side) the effect may be lateralized in left-handed individuals. Twenty-one self-identified left-handed participants grasped food items of three different sizes while grasp kinematics were captured via an Optotrak Certus motion capture array. A main effect of task was identified wherein the grasp-to-eat action generated significantly smaller MGAs than did the grasp-to-place action. Further analysis revealed that similar to the findings in right-handed individuals, this effect was significant only during right-handed movements. Upon further inspection however, we found individual differences in the magnitude and direction of the observed lateralization. These results underscore the evolutionary significance of the grasp-to-eat movement in producing population-level right-handedness in humans as well as highlighting the heterogeneity of the left-handed population.

  1. Kinematic analysis of movement imitation in apraxia

    National Research Council Canada - National Science Library

    Hermsdörfer, J; Mai, N; Spatt, J; Marquardt, C; Veltkamp, R; Goldenberg, G

    1996-01-01

    Accuracy of the final position and kinematics of movement were analysed during the imitation of meaningless gestures in patients with unilateral brain lesions who performed with the hand ipsilateral...

  2. Corticospinal excitability in human voluntary movement

    NARCIS (Netherlands)

    Elswijk, G.A.F. van

    2008-01-01

    The research described in this thesis addressed the neurophysiologic changes in the human corticospinal system during preparation and execution of voluntary hand movements. The experiments involved transcranial magnetic stimulation (TMS) of the motor cortex combined with electromyography (EMG) and e

  3. What makes a movement a gesture?

    Science.gov (United States)

    Novack, Miriam A; Wakefield, Elizabeth M; Goldin-Meadow, Susan

    2016-01-01

    Theories of how adults interpret the actions of others have focused on the goals and intentions of actors engaged in object-directed actions. Recent research has challenged this assumption, and shown that movements are often interpreted as being for their own sake (Schachner & Carey, 2013). Here we postulate a third interpretation of movement-movement that represents action, but does not literally act on objects in the world. These movements are gestures. In this paper, we describe a framework for predicting when movements are likely to be seen as representations. In Study 1, adults described one of three scenes: (1) an actor moving objects, (2) an actor moving her hands in the presence of objects (but not touching them) or (3) an actor moving her hands in the absence of objects. Participants systematically described the movements as depicting an object-directed action when the actor moved objects, and favored describing the movements as depicting movement for its own sake when the actor produced the same movements in the absence of objects. However, participants favored describing the movements as representations when the actor produced the movements near, but not on, the objects. Study 2 explored two additional features-the form of an actor's hands and the presence of speech-like sounds-to test the effect of context on observers' classification of movement as representational. When movements are seen as representations, they have the power to influence communication, learning, and cognition in ways that movement for its own sake does not. By incorporating representational gesture into our framework for movement analysis, we take an important step towards developing a more cohesive understanding of action-interpretation.

  4. Digital repetitive control under varying frequency conditions

    OpenAIRE

    Ramos Fuentes, Germán Andrés

    2012-01-01

    The tracking/rejection of periodic signals constitutes a wide field of research in the control theory and applications area and Repetitive Control has proven to be an efficient way to face this topic; however, in some applications the period of the signal to be tracked/rejected changes in time or is uncertain, which causes and important performance degradation in the standard repetitive controller. This thesis presents some contributions to the open topic of repetitive control workin...

  5. Physiological responses to four hours of low-level repetitive work.

    Science.gov (United States)

    Garde, A Helene; Hansen, Ase M; Jensen, Bente R

    2003-12-01

    The study investigated physiological responses to 4 hours of standardized low-level repetitive work. It was hypothesized that accumulative effects not observed after 1 hour could be found after 4 hours of repetitive work. Ten healthy women performed intermittent (5 seconds + 5 seconds) handgrip contractions at 10% of the maximal voluntary contraction combined with mental demands for concentration and attention. Muscle activity in the working forearm muscles, cardiovascular responses, and concentrations of biomarkers in biological fluids were recorded along with exerted force, performance, and ratings of perceived physical exertion (RPE), and perceived mental exertion. The urinary epinephrine, norepinephrine, and cortisol concentrations were higher during the repetitive task than on a reference day, but only the norepinephrine concentrations increased progressively during the 4 hours. In accordance, the RPE recorded for the hand, forearm, and shoulder regions increased progressively. For the remaining physiological measures, no accumulative changes were found. Forearm muscle activity was higher during a mental reference task with lower exerted force than during the repetitive task. The variation in exerted force was higher during the repetitive task than during a force reference task without mental demands. The urinary biomarkers were increased during the repetitive task. However, only norepinephrine increased progressively during the 4 hours. Forearm muscle activity during a mental reference task with low exerted force indicated attention-related muscle activity. Finally, it was indicated that repetitive work including high demands for attention is performed at the expense of the precision of the exerted force.

  6. 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.

  7. Intrinsic hand muscles and digit independence on the preferred and non-preferred hands of humans.

    Science.gov (United States)

    Reilly, Karen T; Hammond, Geoffrey R

    2006-09-01

    Although the superior dexterity of one hand is an almost ubiquitous human experience, it is unclear which characteristics of the motor system controlling the preferred hand produce this superior dexterity. Between-species studies show that greater dexterity is associated with a motor system that permits more independent movements of the digits. If between-hand dexterity differences are mediated by the same mechanism as between-species dexterity differences, then there should be asymmetries within the corticospinal tracts of humans that would result in between-hand independence differences. The evidence for asymmetries in the corticospinal tracts is sparse, and if an asymmetry does exist, it appears to be limited to the control of intrinsic hand muscles. We wondered, therefore, whether there might be a difference in the degree of independent control on the two hands during performance of a task that primarily uses intrinsic hand muscles. We examined digit individuation when subjects produced abduction or adduction forces with a single digit in isolation. Consistent with previous studies in which forces or movements in single digits were generated primarily by extrinsic hand muscles, we found no difference between the individuation of the digits on the preferred and non-preferred hands. We suggest that whereas independence differences underlie large dexterity differences between species, they do not underlie the more subtle dexterity differences between the preferred and non-preferred hands. Instead, the neural substrate for handedness might be asymmetrical connectivity within M1, with more profuse connections within the dominant than non-dominant M1 imparting a greater potential for excitatory and inhibitory interactions between movement representations which might then result in the more efficient coordination of hand and arm movements of the preferred hand.

  8. [Repetition and fear of dying].

    Science.gov (United States)

    Lerner, B D

    1995-03-01

    In this paper a revision is made of the qualifications of Repetition (R) in Freuds work, i.e. its being at the service of the Pleasure Principle and, beyond it, the binding of free energy due to trauma. Freud intends to explain with this last concept the "fort-da" and the traumatic dreams (obsessively reiterated self-reproaches may be added to them). The main thesis of this work is that R. is not only a defense against the recollection of the ominous past (as in the metaphorical deaths of abandonment and desertion) but also a way of maintaining life and identify fighting against the inescapable omninous future (known but yet experienced), i.e. our own death. Some forms of R. like habits, identificatory behaviors and sometimes even magic, are geared to serve the life instinct. A literary illustration shows this desperate fight.

  9. Pressure rig for repetitive casting

    Science.gov (United States)

    Vasquez, Peter (Inventor); Hutto, William R. (Inventor); Philips, Albert R. (Inventor)

    1989-01-01

    The invention is a pressure rig for repetitive casting of metal. The pressure rig performs like a piston for feeding molten metal into a mold. Pressure is applied to an expandable rubber diaphragm which expands like a balloon to force the metal into the mold. A ceramic cavity which holds molten metal is lined with blanket-type insulating material, necessitating only a relining for subsequent use and eliminating the lengthy cavity preparation inherent in previous rigs. In addition, the expandable rubber diaphragm is protected by the insulating material thereby decreasing its vulnerability to heat damage. As a result of the improved design the life expectancy of the pressure rig contemplated by the present invention is more than doubled. Moreover, the improved heat protection has allowed the casting of brass and other alloys with higher melting temperatures than possible in the conventional pressure rigs.

  10. Automatic Chloroplast Movement Analysis.

    Science.gov (United States)

    Johansson, Henrik; Zeidler, Mathias

    2016-01-01

    In response to low or high intensities of light, the chloroplasts in the mesophyll cells of the leaf are able to increase or decrease their exposure to light by accumulating at the upper and lower sides or along the side walls of the cell respectively. This movement, regulated by the phototropin blue light photoreceptors phot1 and phot2, results in a decreased or increased transmission of light through the leaf. This way the plant is able to optimize harvesting of the incoming light or avoid damage caused by excess light. Here we describe a method that indirectly measures the movement of chloroplasts by taking advantage of the resulting change in leaf transmittance. By using a microplate reader, quantitative measurements of chloroplast accumulation or avoidance can be monitored over time, for multiple samples with relatively little hands-on time.

  11. Programming of left hand exploits task set but that of right hand depends on recent history.

    Science.gov (United States)

    Tang, Rixin; Zhu, Hong

    2017-07-01

    There are many differences between the left hand and the right hand. But it is not clear if there is a difference in programming between left hand and right hand when the hands perform the same movement. In current study, we carried out two experiments to investigate whether the programming of two hands was equivalent or they exploited different strategies. In the first experiment, participants were required to use one hand to grasp an object with visual feedback or to point to the center of one object without visual feedback on alternate trials, or to grasp an object without visual feedback and to point the center of one object with visual feedback on alternating trials. They then performed the tasks with the other hand. The result was that previous pointing task affected current grasping when it was performed by the left hand, but not the right hand. In experiment 2, we studied if the programming of the left (or right) hand would be affected by the pointing task performed on the previous trial not only by the same hand, but also by the right (or left) hand. Participants pointed and grasped the objects alternately with two hands. The result was similar with Experiment 1, i.e., left-hand grasping was affected by right-hand pointing, whereas right-hand grasping was immune from the interference from left hand. Taken together, the results suggest that when open- and closed-loop trials are interleaved, motor programming of grasping with the right hand was affected by the nature of the online feedback on the previous trial only if it was a grasping trial, suggesting that the trial-to-trial transfer depends on sensorimotor memory and not on task set. In contrast, motor programming of grasping with the left hand can use information about the nature of the online feedback on the previous trial to specify the parameters of the movement, even when the type of movement that occurred was quite different (i.e., pointing) and was performed with the right hand. This suggests that

  12. Virtual immersion for post-stroke hand rehabilitation therapy.

    Science.gov (United States)

    Tsoupikova, Daria; Stoykov, Nikolay S; Corrigan, Molly; Thielbar, Kelly; Vick, Randy; Li, Yu; Triandafilou, Kristen; Preuss, Fabian; Kamper, Derek

    2015-02-01

    Stroke is the leading cause of serious, long-term disability in the United States. Impairment of upper extremity function is a common outcome following stroke, often to the detriment of lifestyle and employment opportunities. While the upper extremity is a natural target for therapy, treatment may be hampered by limitations in baseline capability as lack of success may discourage arm and hand use. We developeda virtual reality (VR) system in order to encourage repetitive task practice. This system combined an assistive glove with a novel VR environment. A set of exercises for this system was developed to encourage specific movements. Six stroke survivors with chronic upper extremity hemiparesis volunteered to participate in a pilot study in which they completed 18 one-hour training sessions with the VR system. Performance with the system was recorded across the 18 training sessions. Clinical evaluations of motor control were conducted at three time points: prior to initiation of training, following the end of training, and 1 month later. Subjects displayed significant improvement on performance of the virtual tasks over the course of the training, although for the clinical outcome measures only lateral pinch showed significant improvement. Future expansion to multi-user virtual environments may extend the benefits of this system for stroke survivors with hemiparesis by furthering engagement in the rehabilitation exercises.

  13. Elbow joint variability for different hand positions of the round off in gymnastics.

    Science.gov (United States)

    Farana, Roman; Irwin, Gareth; Jandacka, Daniel; Uchytil, Jaroslav; Mullineaux, David R

    2015-02-01

    The aim of the present study was to conduct within-gymnast analyses of biological movement variability in impact forces, elbow joint kinematics and kinetics of expert gymnasts in the execution of the round-off with different hand positions. Six international level female gymnasts performed 10 trials of the round-off from a hurdle step to a back-handspring using two hand potions: parallel and T-shape. Two force plates were used to determine ground reaction forces. Eight infrared cameras were employed to collect the kinematic data automatically. Within gymnast variability was calculated using biological coefficient of variation (BCV) discretely for ground reaction force, kinematic and kinetic measures. Variability of the continuous data was quantified using coefficient of multiple correlations (CMC). Group BCV and CMC were calculated and T-test with effect size statistics determined differences between the variability of the two techniques examined in this study. The major observation was a higher level of biological variability in the elbow joint abduction angle and adduction moment of force in the T-shaped hand position. This finding may lead to a reduced repetitive abduction stress and thus protect the elbow joint from overload. Knowledge of the differences in biological variability can inform clinicians and practitioners with effective skill selection. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Mixed Movements

    DEFF Research Database (Denmark)

    Brabrand, Helle

    2010-01-01

    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...... 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...... as possible operational moves....

  15. Differential modulation of STN-cortical and cortico-muscular coherence by movement and levodopa in Parkinson's disease.

    Science.gov (United States)

    Hirschmann, J; Özkurt, T E; Butz, M; Homburger, M; Elben, S; Hartmann, C J; Vesper, J; Wojtecki, L; Schnitzler, A

    2013-03-01

    Previous research suggests that oscillatory coupling between cortex, basal ganglia and muscles plays an important role in motor behavior. Furthermore, there is evidence that oscillatory coupling is altered in patients with movement disorders such as Parkinson's disease (PD). In this study, we performed simultaneous magnetoencephalography (MEG), local field potential (LFP) and electromyogram (EMG) recordings in PD patients selected for therapeutic subthalamic nucleus (STN) stimulation. Patients were recorded (i) after withdrawal of anti-parkinsonian medication (OFF) and (ii) after levodopa administration (ON). We analyzed STN-cortical and cortico-muscular coherence during static forearm contraction and repetitive hand movement in order to evaluate modulations of coherence by movement and medication. Based on previous results from studies investigating resting state coherence in PD patients, we selected primary motor cortex (M1) and superior temporal gyrus (STG) as regions of interest. We found beta coherence between M1 and STN to be suppressed by administration of levodopa. M1-muscular coherence was strongly reduced in the alpha and beta band during repetitive movement compared to static contraction, but was unaffected by administration of levodopa. Strong STG-STN but not STG-muscular coherence could be observed in the alpha band. Coherence with STG was modulated neither by movement nor by medication. Finally, we found both M1-STN and M1-muscular beta coherence to be negatively correlated with UPDRS akinesia and rigidity sub-scores in the OFF state. The present study provides new insights into the functional roles of STN-cortical and cortico-muscular coherence and their relationship to PD symptoms. The results indicate that STN-cortical and cortico-muscular coupling are correlated, but can be modulated independently. Moreover, they show differences in their frequency-specific topography. We conclude that they represent partly independent sub-loops within the motor

  16. Hand kinematics of piano playing.

    Science.gov (United States)

    Furuya, Shinichi; Flanders, Martha; Soechting, John F

    2011-12-01

    Dexterous use of the hand represents a sophisticated sensorimotor function. In behaviors such as playing the piano, it can involve strong temporal and spatial constraints. The purpose of this study was to determine fundamental patterns of covariation of motion across joints and digits of the human hand. Joint motion was recorded while 5 expert pianists played 30 excerpts from musical pieces, which featured ∼50 different tone sequences and fingering. Principal component analysis and cluster analysis using an expectation-maximization algorithm revealed that joint velocities could be categorized into several patterns, which help to simplify the description of the movements of the multiple degrees of freedom of the hand. For the thumb keystroke, two distinct patterns of joint movement covariation emerged and they depended on the spatiotemporal patterns of the task. For example, the thumb-under maneuver was clearly separated into two clusters based on the direction of hand translation along the keyboard. While the pattern of the thumb joint velocities differed between these clusters, the motions at the metacarpo-phalangeal and proximal-phalangeal joints of the four fingers were more consistent. For a keystroke executed with one of the fingers, there were three distinct patterns of joint rotations, across which motion at the striking finger was fairly consistent, but motion of the other fingers was more variable. Furthermore, the amount of movement spillover of the striking finger to the adjacent fingers was small irrespective of the finger used for the keystroke. These findings describe an unparalleled amount of independent motion of the fingers.

  17. Epithelial topography for repetitive tooth formation

    Directory of Open Access Journals (Sweden)

    Marcia Gaete

    2015-12-01

    Full Text Available During the formation of repetitive ectodermally derived organs such as mammary glands, lateral line and teeth, the tissue primordium iteratively initiates new structures. In the case of successional molar development, new teeth appear sequentially in the posterior region of the jaw from Sox2+ cells in association with the posterior aspect of a pre-existing tooth. The sequence of molar development is well known, however, the epithelial topography involved in the formation of a new tooth is unclear. Here, we have examined the morphology of the molar dental epithelium and its development at different stages in the mouse in vivo and in molar explants. Using regional lineage tracing we show that within the posterior tail of the first molar the primordium for the second and third molar are organized in a row, with the tail remaining in connection with the surface, where a furrow is observed. The morphology and Sox2 expression of the tail retains characteristics reminiscent of the earlier stages of tooth development, such that position along the A-P axes of the tail correlates with different temporal stages. Sox9, a stem/progenitor cell marker in other organs, is expressed mainly in the suprabasal epithelium complementary with Sox2 expression. This Sox2 and Sox9 expressing molar tail contains actively proliferating cells with mitosis following an apico-basal direction. Snail2, a transcription factor implicated in cell migration, is expressed at high levels in the tip of the molar tail while E-cadherin and laminin are decreased. In conclusion, our studies propose a model in which the epithelium of the molar tail can grow by posterior movement of epithelial cells followed by infolding and stratification involving a population of Sox2+/Sox9+ cells.

  18. 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 define...

  19. Characterization and distribution of repetitive elements in association with genes in the human genome.

    Science.gov (United States)

    Liang, Kai-Chiang; Tseng, Joseph T; Tsai, Shaw-Jenq; Sun, H Sunny

    2015-08-01

    Repetitive elements constitute more than 50% of the human genome. Recent studies implied that the complexity of living organisms is not just a direct outcome of a number of coding sequences; the repetitive elements, which do not encode proteins, may also play a significant role. Though scattered studies showed that repetitive elements in the regulatory regions of a gene control gene expression, no systematic survey has been done to report the characterization and distribution of various types of these repetitive elements in the human genome. Sequences from 5' and 3' untranslated regions and upstream and downstream of a gene were downloaded from the Ensembl database. The repetitive elements in the neighboring of each gene were identified and classified using cross-matching implemented in the RepeatMasker. The annotation and distribution of distinct classes of repetitive elements associated with individual gene were collected to characterize genes in association with different types of repetitive elements using systems biology program. We identified a total of 1,068,400 repetitive elements which belong to 37-class families and 1235 subclasses that are associated with 33,761 genes and 57,365 transcripts. In addition, we found that the tandem repeats preferentially locate proximal to the transcription start site (TSS) of genes and the major function of these genes are involved in developmental processes. On the other hand, interspersed repetitive elements showed a tendency to be accumulated at distal region from the TSS and the function of interspersed repeat-containing genes took part in the catabolic/metabolic processes. Results from the distribution analysis were collected and used to construct a gene-based repetitive element database (GBRED; http://www.binfo.ncku.edu.tw/GBRED/index.html). A user-friendly web interface was designed to provide the information of repetitive elements associated with any particular gene(s). This is the first study focusing on the gene

  20. Chloroplast movement.

    Science.gov (United States)

    Wada, Masamitsu

    2013-09-01

    Chloroplast movement is important for plant survival under high light and for efficient photosynthesis under low light. This review introduces recent knowledge on chloroplast movement and shows how to analyze the responses and the moving mechanisms, potentially inspiring research in this field. Avoidance from the strong light is mediated by blue light receptor phototropin 2 (phot2) plausibly localized on the chloroplast envelop and accumulation at the week light-irradiated area is mediated by phot1 and phot2 localized on the plasma membrane. Chloroplasts move by chloroplast actin (cp-actin) filaments that must be polymerized by Chloroplast Unusual Positioning1 (CHUP1) at the front side of moving chloroplast. To understand the signal transduction pathways and the mechanism of chloroplast movement, that is, from light capture to motive force-generating mechanism, various methods should be employed based on the various aspects. Observation of chloroplast distribution pattern under different light condition by fixed cell sectioning is somewhat an old-fashioned technique but the most basic and important way. However, most importantly, precise chloroplast behavior during and just after the induction of chloroplast movement by partial cell irradiation using an irradiator with either low light or strong light microbeam should be recorded by time lapse photographs under infrared light and analyzed. Recently various factors involved in chloroplast movement, such as cp-actin filaments and CHUP1, could be traced in Arabidopsis transgenic lines with fluorescent protein tags under a confocal laser scanning microscope (CLSM) and/or a total internal reflection fluorescence microscope (TIRFM). These methods are listed and their advantages and disadvantages are evaluated.

  1. Comparing repetition-based melody segmentation models

    NARCIS (Netherlands)

    Rodríguez López, M.E.; de Haas, Bas; Volk, Anja

    2014-01-01

    This paper reports on a comparative study of computational melody segmentation models based on repetition detection. For the comparison we implemented five repetition-based segmentation models, and subsequently evaluated their capacity to automatically find melodic phrase boundaries in a corpus of 2

  2. Task Repetition and Second Language Speech Processing

    Science.gov (United States)

    Lambert, Craig; Kormos, Judit; Minn, Danny

    2017-01-01

    This study examines the relationship between the repetition of oral monologue tasks and immediate gains in L2 fluency. It considers the effect of aural-oral task repetition on speech rate, frequency of clause-final and midclause filled pauses, and overt self-repairs across different task types and proficiency levels and relates these findings to…

  3. Repetitions: A Cross-Cultural Study.

    Science.gov (United States)

    Murata, Kumiko

    1995-01-01

    This study investigated how repetition is used in conversation among native speakers of British English, native speakers of Japanese, and Japanese speakers of English. Five interactional functions of repetition (interruption-orientated, solidarity, silence-avoidance, hesitation, and reformulation) were identified, as well as the cultural factors…

  4. Hand Dominance and Common Hand Conditions.

    Science.gov (United States)

    Lutsky, Kevin; Kim, Nayoung; Medina, Juana; Maltenfort, Mitchell; Beredjiklian, Pedro K

    2016-05-01

    The goals of this study were to (1) assess how frequently patients present for evaluation of common hand disorders in relation to hand dominance and (2) evaluate the effect of hand dominance on function in patients with these conditions. The authors hypothesized that (1) the majority of patients who seek evaluation would have a condition that affects the dominant hand, and (2) disability scores would be worse if the dominant hand is involved. They retrospectively reviewed the records of consecutive patients who presented for treatment to their institution with unilateral symptoms of 5 common disorders of the hand: carpal tunnel syndrome (CTS), de Quervain's tenosynovitis (DEQ), lateral epicondylitis (LE), hand osteoarthritis (OA), and trigger finger (TF). The authors assessed the effect of diagnosis and hand dominance on Disabilities of the Arm, Shoulder and Hand (DASH) scores. The study group comprised 1029 patients (379 men and 650 women) with a mean age of 59.5 years. Ninety percent were right-hand dominant. The dominant and nondominant hands were affected with relatively equal frequency for CTS, DEQ, OA, and TF (range, 45%-53%). Patients with LE had a significantly higher incidence of dominant hand involvement. Men had lower DASH scores than women by an average of 7.9 points, and DASH scores were significantly but slightly higher for the overall group (3.2 points) when the dominant side was affected. Men with LE and women with TF and OA had significantly higher DASH scores when their dominant extremity was affected. Common hand disorders such as CTS, DEQ, OA, and TF affect the dominant and nondominant hands in roughly equivalent proportions, whereas LE is more common on the dominant side. Dominant hand involvement results in significantly worse DASH scores, although the magnitude of this is relatively small. Women have significantly higher DASH scores than men for the conditions evaluated. [Orthopedics. 2016; 39(3):e444-e448.].

  5. Use of a pneumatic glove for hand rehabilitation following stroke.

    Science.gov (United States)

    Connelly, Lauri; Stoykov, Mary Ellen; Jia, Yicheng; Toro, Maria L; Kenyon, Robert V; Kamper, Derek G

    2009-01-01

    Hand impairment is common following stroke and is often resistant to traditional therapy methods. Successful interventions have stressed the importance of repeated practice to facilitate rehabilitation. Thus, we have developed a servo-controlled glove to assist extension of individual digits to promote practice of grasp-and-release movements with the hand. This glove, the PneuGlove, permits free movement of the arm throughout its workspace. A novel immersive virtual reality environment was created for training movement in conjunction with the device. Seven stroke survivors with chronic hand impairment participated in 18 training sessions with the PneuGlove over 6 weeks. Overall, subjects displayed a significant 6-point improvement in the upper extremity score on the Fugl-Meyer assessment and this increase was maintained at the evaluation held one month after conclusion of all training (p hand/wrist score (3.8-point increase, p rehabilitative training of hand movements after stroke.

  6. Investigation of Fatigability during Repetitive Robot-Mediated Arm Training in People with Multiple Sclerosis.

    Directory of Open Access Journals (Sweden)

    Deborah Severijns

    Full Text Available People with multiple sclerosis (MS are encouraged to engage in exercise programs but an increased experience of fatigue may impede sustained participation in training sessions. A high number of movements is, however, needed for obtaining optimal improvements after rehabilitation.This cross-sectional study investigated whether people with MS show abnormal fatigability during a robot-mediated upper limb movement trial. Sixteen people with MS and sixteen healthy controls performed five times three minutes of repetitive shoulder anteflexion movements. Movement performance, maximal strength, subjective upper limb fatigue and surface electromyography (median frequency and root mean square of the amplitude of the electromyography (EMG signal of the anterior deltoid were recorded during or in-between these exercises. After fifteen minutes of rest, one extra movement bout was performed to investigate how rest influences performance.A fifteen minutes upper limb movement protocol increased the perceived upper limb fatigue and induced muscle fatigue, given a decline in maximal anteflexion strength and changes of both the amplitude and the median frequency of EMG the anterior deltoid. In contrast, performance during the 3 minutes of anteflexion movements did not decline. There was no relation between changes in subjective fatigue and the changes in the amplitude and the median frequency of the anterior deltoid muscle, however, there was a correlation between the changes in subjective fatigue and changes in strength in people with MS. People with MS with upper limb weakness report more fatigue due to the repetitive movements, than people with MS with normal upper limb strength, who are comparable to healthy controls. The weak group could, however, keep up performance during the 15 minutes of repetitive movements.Albeit a protocol of repetitive shoulder anteflexion movements did not elicit a performance decline, fatigue feelings clearly increased in both

  7. Digital repetitive control under varying frequency conditions

    CERN Document Server

    Ramos, Germán A; Olm, Josep M

    2013-01-01

    The tracking/rejection of periodic signals constitutes a wide field of research in the control theory and applications area. Repetitive Control has proven to be an efficient way to face this topic. However, in some applications the frequency of the reference/disturbance signal is time-varying or uncertain. This causes an important performance degradation in the standard Repetitive Control scheme. This book presents some solutions to apply Repetitive Control in varying frequency conditions without loosing steady-state performance. It also includes a complete theoretical development and experimental results in two representative systems. The presented solutions are organized in two complementary branches: varying sampling period Repetitive Control and High Order Repetitive Control. The first approach allows dealing with large range frequency variations while the second allows dealing with small range frequency variations. The book also presents applications of the described techniques to a Roto-magnet plant and...

  8. 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......-effects model for analyzing temporally continuous signals that contain systematic effects in both timing and path. Identifiability issues of path relative to timing are overcome by using maximum likelihood estimation in which the most likely separation of space and time is chosen given the variation found...

  9. Etiological factors of carpal tunnel syndrome in subjects occupationally exposed to monotype wrist movements

    Directory of Open Access Journals (Sweden)

    Magdalena Lewańska

    2014-04-01

    Full Text Available Background: Carpal tunnel syndrome (CTS is the most common neuropathy of upper limbs and a leading cause of upper extremity musculoskeletal disorders, in terms of work exposure, repetitive and forceful exertions of the hand and use of vibrating hand tools. The aim of the study was to evaluate etiological factors of carpal tunnel syndrome in subjects occupationally exposed to monotype movements in wrist. Material and Methods: We conducted the retrospective analysis of 300 patients (261 women, 39 men, mean age 52 years (standard deviation: ±6.93 hospitalized with the suspicion of occupational CTS. Results: The study revealed high percentage (68.7% of diseases and systemic factors involved in the pathogenesis of CTS in the analyzed population, especially obesity (32%, thyroid diseases (28.7%, hormone replacement therapy and/or oophorectomy (16.3% and diabetes mellitus (12%. In 111 patients the coexistence of at least a couple of potential etiological factors of the neuropathy was recognized. Clinical analysis and occupational exposure allowed to diagnose occupational carpal tunnel syndrome in 18 (6% patients only. The undeniable long-term (20.2±9.3 years occupational exposure to repetitive, forceful movements in the wrist was observed in this group. Conclusion: The results of our study indicated that non-occupational etiological factors of CTS predominated and in 37% of patients at least several factors were found. The analysis showed the high prevalence of CTS in workers employed in various sectors of industry, including so called "blue collar" workers. Our study confirmed the multifactorial etiology of carpal tunnel syndrome, however, occupational agents contributed to only 6% of cases. Med Pr 2014;65(2:261–270

  10. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... children, parents, and public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand Hygiene Saves Lives Hand Hygiene Saves Lives Transcript [28 KB, 2 pages] High ...

  11. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... including, children, parents, and public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand Hygiene Saves Lives Hand Hygiene Saves Lives Transcript [28 KB, 2 pages] High ...

  12. Hand Hygiene Saves Lives

    Science.gov (United States)

    ... including, children, parents, and public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand Hygiene Saves Lives Hand Hygiene Saves Lives Transcript [28 KB, 2 pages] High ...

  13. Guideline Implementation: Hand Hygiene.

    Science.gov (United States)

    Goldberg, Judith L

    2017-02-01

    Performing proper hand hygiene and surgical hand antisepsis is essential to reducing the rates of health care-associated infections, including surgical site infections. The updated AORN "Guideline for hand hygiene" provides guidance on hand hygiene and surgical hand antisepsis, the wearing of fingernail polish and artificial nails, proper skin care to prevent dermatitis, the wearing of jewelry, hand hygiene product selection, and quality assurance and performance improvement considerations. This article focuses on key points of the guideline to help perioperative personnel make informed decisions about hand hygiene and surgical hand antisepsis. The key points address the necessity of keeping fingernails and skin healthy, not wearing jewelry on the hands or wrists in the perioperative area, properly performing hand hygiene and surgical hand antisepsis, and involving patients and visitors in hand hygiene initiatives. Perioperative RNs should review the complete guideline for additional information and for guidance when writing and updating policies and procedures.

  14. Strategies for Using Repetition as a Powerful Teaching Tool

    Science.gov (United States)

    Saville, Kirt

    2011-01-01

    Brain research indicates that repetition is of vital importance in the learning process. Repetition is an especially useful tool in the area of music education. The success of repetition can be enhanced by accurate and timely feedback. From "simple repetition" to "repetition with the addition or subtraction of degrees of freedom," there are many…

  15. Strategies for Using Repetition as a Powerful Teaching Tool

    Science.gov (United States)

    Saville, Kirt

    2011-01-01

    Brain research indicates that repetition is of vital importance in the learning process. Repetition is an especially useful tool in the area of music education. The success of repetition can be enhanced by accurate and timely feedback. From "simple repetition" to "repetition with the addition or subtraction of degrees of freedom," there are many…

  16. Repetition priming from moving faces.

    Science.gov (United States)

    Lander, Karen; Bruce, Vicki

    2004-06-01

    Recent experiments have suggested that seeing a familiar face move provides additional dynamic information to the viewer, useful in the recognition of identity. In four experiments, repetition priming was used to investigate whether dynamic information is intrinsic to the underlying face representations. The results suggest that a moving image primes more effectively than a static image, even when the same static image is shown in the prime and the test phases (Experiment 1). Furthermore, when moving images are presented in the test phase (Experiment 2), there is an advantage for moving prime images. The most priming advantage is found with naturally moving faces, rather than with those shown in slow motion (Experiment 3). Finally, showing the same moving sequence at prime and test produced more priming than that found when different moving sequences were shown (Experiment 4). The results suggest that dynamic information is intrinsic to the face representations and that there is an advantage to viewing the same moving sequence at prime and test.

  17. Biomimetic hand exotendon device (BiomHED) for functional hand rehabilitation in stroke.

    Science.gov (United States)

    Lee, Sang Wook; Landers, Katlin A; Park, Hyung-Soon

    2013-06-01

    Significant functional impairment of the hand is commonly observed among stroke survivors. In order to restore the functional use of the affected hand, we developed a biomimetic device that assists in generating functional movements of the hand. The device is actuated by exotendons that replicate the kinetic functional of the hand muscle-tendons, therefore it can reproduce the spatial finger joint coordination patterns of the functional manual tasks (e.g., power grip and pinch) with a reduced number of actuators. The system includes a thumb actuation mechanism, whose action is coordinated with finger exotendons to perform various manual tasks, thereby restoring the functional use of the hand. This paper presents the design of the device and the preliminary data of the functional movement generation by the system.

  18. Bilaterally impaired hand dexterity with posterior cortical atrophy

    Directory of Open Access Journals (Sweden)

    Nages Nagaratnam, MD, FRACP, FRCPA, FACC

    2015-12-01

    Full Text Available A 79-year- old man presented with bilaterally impaired hand movements pertaining to handling of objects although hand movements without the use of objects were preserved, findings consistent with tactile apraxia. His hand and finger movements were slow and clumsy. He had an isolated optic ataxia, a component of Balint's syndrome. The computed tomography scan showed enlargement of the posterior horns of the lateral ventricles. He had recurrent falls probably owing to visual attentional deficits, which may be present in patients with posterior cortical atrophy. The findings can be deemed to fall within the posterior cortical atrophy spectrum. The underlying mechanisms are discussed.

  19. 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.

  20. Antinuclear movement

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Hee; Im, Jaeg Yeong

    1988-08-15

    This book is for antinuclear movement. So, this book introduces many articles on nuclear issues of Asia and the pacific area. The titles of articles are the crusades of Reagan by Werner Plaha, contending between super powers in Europe by Alva Reimer Myrdal, claims of resistance by Daniel Ellsberg, nuclear and the Korean Peninsula by Go, Seung Woo, Liberation but of belief of nuclear weapon by Lee, Young Hee and nuclear weapon in Korea by peter Haze.

  1. Evidence of common and separate eye and hand accumulators underlying flexible eye-hand coordination.

    Science.gov (United States)

    Jana, Sumitash; Gopal, Atul; Murthy, Aditya

    2017-01-01

    Eye and hand movements are initiated by anatomically separate regions in the brain, and yet these movements can be flexibly coupled and decoupled, depending on the need. The computational architecture that enables this flexible coupling of independent effectors is not understood. Here, we studied the computational architecture that enables flexible eye-hand coordination using a drift diffusion framework, which predicts that the variability of the reaction time (RT) distribution scales with its mean. We show that a common stochastic accumulator to threshold, followed by a noisy effector-dependent delay, explains eye-hand RT distributions and their correlation in a visual search task that required decision-making, while an interactive eye and hand accumulator model did not. In contrast, in an eye-hand dual task, an interactive model better predicted the observed correlations and RT distributions than a common accumulator model. Notably, these two models could only be distinguished on the basis of the variability and not the means of the predicted RT distributions. Additionally, signatures of separate initiation signals were also observed in a small fraction of trials in the visual search task, implying that these distinct computational architectures were not a manifestation of the task design per se. Taken together, our results suggest two unique computational architectures for eye-hand coordination, with task context biasing the brain toward instantiating one of the two architectures. Previous studies on eye-hand coordination have considered mainly the means of eye and hand reaction time (RT) distributions. Here, we leverage the approximately linear relationship between the mean and standard deviation of RT distributions, as predicted by the drift-diffusion model, to propose the existence of two distinct computational architectures underlying coordinated eye-hand movements. These architectures, for the first time, provide a computational basis for the flexible

  2. Constraint Study for a Hand Exoskeleton: Human Hand Kinematics and Dynamics

    Directory of Open Access Journals (Sweden)

    Fai Chen Chen

    2013-01-01

    Full Text Available In the last few years, the number of projects studying the human hand from the robotic point of view has increased rapidly, due to the growing interest in academic and industrial applications. Nevertheless, the complexity of the human hand given its large number of degrees of freedom (DoF within a significantly reduced space requires an exhaustive analysis, before proposing any applications. The aim of this paper is to provide a complete summary of the kinematic and dynamic characteristics of the human hand as a preliminary step towards the development of hand devices such as prosthetic/robotic hands and exoskeletons imitating the human hand shape and functionality. A collection of data and constraints relevant to hand movements is presented, and the direct and inverse kinematics are solved for all the fingers as well as the dynamics; anthropometric data and dynamics equations allow performing simulations to understand the behavior of the finger.

  3. Mirror symmetric bimanual movement priming can increase corticomotor excitability and enhance motor learning.

    Directory of Open Access Journals (Sweden)

    Winston D Byblow

    Full Text Available Repetitive mirror symmetric bilateral upper limb may be a suitable priming technique for upper limb rehabilitation after stroke. Here we demonstrate neurophysiological and behavioural after-effects in healthy participants after priming with 20 minutes of repetitive active-passive bimanual wrist flexion and extension in a mirror symmetric pattern with respect to the body midline (MIR compared to an control priming condition with alternating flexion-extension (ALT. Transcranial magnetic stimulation (TMS indicated that corticomotor excitability (CME of the passive hemisphere remained elevated compared to baseline for at least 30 minutes after MIR but not ALT, evidenced by an increase in the size of motor evoked potentials in ECR and FCR. Short and long-latency intracortical inhibition (SICI, LICI, short afferent inhibition (SAI and interhemispheric inhibition (IHI were also examined using pairs of stimuli. LICI differed between patterns, with less LICI after MIR compared with ALT, and an effect of pattern on IHI, with reduced IHI in passive FCR 15 minutes after MIR compared with ALT and baseline. There was no effect of pattern on SAI or FCR H-reflex. Similarly, SICI remained unchanged after 20 minutes of MIR. We then had participants complete a timed manual dexterity motor learning task with the passive hand during, immediately after, and 24 hours after MIR or control priming. The rate of task completion was faster with MIR priming compared to control conditions. Finally, ECR and FCR MEPs were examined within a pre-movement facilitation paradigm of wrist extension before and after MIR. ECR, but not FCR, MEPs were consistently facilitated before and after MIR, demonstrating no degradation of selective muscle activation. In summary, mirror symmetric active-passive bimanual movement increases CME and can enhance motor learning without degradation of muscle selectivity. These findings rationalise the use of mirror symmetric bimanual movement as a

  4. Movement constraints on interpersonal coordination and communication.

    Science.gov (United States)

    Tolston, Michael T; Shockley, Kevin; Riley, Michael A; Richardson, Michael J

    2014-10-01

    The present study investigated how constraining movement affects interpersonal coordination and joint cognitive performance. Pairs of participants worked cooperatively to solve picture-puzzle tasks in which they conversed to identify differences between pictures in 3 degree-of-constraint conditions: both participants were free to move their hands (free-free; FF); both participants' hands were restrained (restrained-restrained; RR); and the hands of 1 participant were free while the hands of the other participant were restrained (free-restrained; FR). Eye tracking data were collected, and movement was measured at the waist, hand, and head. Data were analyzed using Cross-Recurrence Quantification Analysis (CRQ). Postural sway coordination, gaze coordination, and task performance were predicted to be highest in FF, followed by RR, and then by FR. Results showed the asymmetric FR condition generally exhibited lesser degrees of coordination than the symmetric Conditions FF and RR, and that the patterning of coordination in the symmetric conditions varied across the measured body segments. These results demonstrate that movement restraints affect not only interpersonal postural coordination, but also joint attention. Additionally, significant positive relationships were found between task performance and total amount of anterior-posterior movement measured at the head, hand and waist; number of utterances; and number of differences pairs found in the puzzles. These findings indicate a relationship between movement and task performance consistent with the hypotheses that both interpersonal coordination and cognitive performance are sensitive to local action constraints.

  5. 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

  6. Continuous passive movement does not influence motor maps in healthy adults

    Directory of Open Access Journals (Sweden)

    Michelle Nadine McDonnell

    2015-04-01

    Full Text Available Hand weakness following stroke is often associated with a reduced representation of the hand in the primary motor cortex. Meaningful sensory input can induce sensorimotor reorganisation in the brain, but the effect of continuous passive motion on the cortical representation is unknown. The purpose of this study was to determine whether repeated sessions of continuous passive movement (CPM of the thumb induce a lasting increase in the motor cortical representation of a thumb muscle in healthy adults. Thirteen right-handed healthy adults (mean age 24.3 ± 4.3 yrs participated in the study. Single-pulse Transcranial Magnetic Stimulation (TMS was delivered over the motor area of the target muscle (abductor pollicis brevis before and/or after a thirty minute session of thumb CPM administered on three consecutive days. TMS was also delivered five days after cessation of the CPM intervention. The response to TMS (motor evoked potential was recorded in the target muscle with surface EMG. Resting motor threshold, motor evoked potential amplitude at a specified intensity, and the area and volume of the cortical representation of the target muscle were measured. Thumb CPM had no significant effect on TMS parameters (p > 0.05 all measures and performance of an attention task remained unchanged within and across CPM sessions. The results suggest that three sessions of repetitive passive thumb movement is not sufficient to induce a change in the cortical representation of the thumb and is unlikely to reverse the decreased representation of the affected hand following stroke.

  7. Trichotillomania, stereotypic movement disorder, and related disorders.

    Science.gov (United States)

    Stein, Dan J; Garner, Joseph P; Keuthen, Nancy J; Franklin, Martin E; Walkup, John T; Woods, Douglas W

    2007-08-01

    Trichotillomania is currently classified as an impulse control disorder not otherwise classified, whereas body-focused behaviors other than hair-pulling may be diagnosed as stereotypic movement disorder. A number of disorders characterized by repetitive, body-focused behaviors (eg, skin-picking) are prevalent and disabling and may have phenomenological and psychobiological overlap. Such disorders deserve greater recognition in the official nosology, and there would seem to be clinical utility in classifying them in the same diagnostic category.

  8. Mechatronic hands prosthetic and robotic design

    CERN Document Server

    Chappell, Paul Hammond

    2016-01-01

    This book describes the technical design characteristics of the main components that go into forming an artificial hand whether it is a simple design that does not have a natural appearance or a more complicated design where there are multiple movements of the fingers and thumb.

  9. Corticospinal modulations during bimanual movement with different relative phases

    Directory of Open Access Journals (Sweden)

    Yoshifumi eNomura

    2016-03-01

    Full Text Available The purpose of this study was to investigate corticospinal modulation of bimanual movement with different relative phases (RPs. The participants rhythmically abducted and adducted the right index finger (unimanual movement or both index fingers (bimanual movement with a cyclic duration of 1 s. The RP of bimanual movement, defined as the time difference between one hand movement and the other hand movement, was 0°, 90°, or 180°. Motor evoked potentials in the right flexor dorsal interosseous muscle elicited by transcranial magnetic stimulation were obtained during unimanual or bimanual movement. Corticospinal excitability in the first dorsal interosseous muscle during bimanual movement with 90° RP was higher than that during unimanual movement or bimanual movement with 0° or 180° RP. The correlation between muscle activity level and corticospinal excitability during bimanual movement with 90° RP was smaller than that during unimanual movement or bimanual movement with 0° or 180° RP. The higher corticospinal excitability during bimanual movement with 90° RP may be caused by the greater effort expended to execute a difficult task, the involvement of interhemispheric interaction, a motor binding process, or task acquisition. The lower dependency of corticospinal excitability on the muscle activity level during bimanual movement with 90° RP may reflect the minor corticospinal contribution to bimanual movement with an RP that is not in the attractor state.

  10. Stereotyped movement disorder in ICD-11.

    Science.gov (United States)

    Stein, Dan J; Woods, Douglas W

    2014-01-01

    According to current proposals for ICD-11, stereotyped movement disorder will be classified in the grouping of neurodevelopmental disorders, with a qualifier to indicate whether self-injury is present, similar to the classification of stereotypic movement disorder in DSM-5. At the same time, the WHO ICD-11 Working Group on the Classification of Obsessive-Compulsive and Related Disorders has proposed a grouping of body-focused repetitive behavior disorders within the obsessive-compulsive and related disorders (OCRD) cluster to include trichotillomania and skin-picking disorder. DSM-5 has taken a slightly different approach: trichotillomania and excoriation (skin picking) disorder are included in the OCRD grouping, while body-focused repetitive behavior disorder is listed under other specified forms of OCRD. DSM-5 also includes a separate category of nonsuicidal self-injury in the section on "conditions for further study." There are a number of unresolved nosological questions regarding the relationships among stereotyped movement disorder, body-focused repetitive behavior disorders, and nonsuicidal self-injury. In this article, we attempt to provide preliminary answers to some of these questions as they relate to the ICD-11 classification of mental and behavioral disorders.

  11. A vacuum-sealed, gigawatt-class, repetitively pulsed high-power microwave source

    Science.gov (United States)

    Xun, Tao; Fan, Yu-wei; Yang, Han-wu; Zhang, Zi-cheng; Chen, Dong-qun; Zhang, Jian-de

    2017-06-01

    A compact L-band sealed-tube magnetically insulated transmission line oscillator (MILO) has been developed that does not require bulky external vacuum pump for repetitive operations. This device with a ceramic insulated vacuum interface, a carbon fiber array cathode, and non-evaporable getters has a base vacuum pressure in the low 10-6 Pa range. A dynamic 3-D Monte-Carlo model for the molecular flow movement and collision was setup for the MILO chamber. The pulse desorption, gas evolution, and pressure distribution were exactly simulated. In the 5 Hz repetition rate experiments, using a 600 kV diode voltage and 48 kA beam current, the average radiated microwave power for 25 shots is about 3.4 GW in 45 ns pulse duration. The maximum equilibrium pressure is below 4.0 × 10-2 Pa, and no pulse shortening limitations are observed during the repetitive test in the sealed-tube condition.

  12. Repetitive Bibliographical Information in Relational Databases.

    Science.gov (United States)

    Brooks, Terrence A.

    1988-01-01

    Proposes a solution to the problem of loading repetitive bibliographic information in a microcomputer-based relational database management system. The alternative design described is based on a representational redundancy design and normalization theory. (12 references) (Author/CLB)

  13. Computer-Related Repetitive Stress Injuries

    Science.gov (United States)

    ... on the shoulder Epicondylitis: elbow soreness often called "tennis elbow" Ganglion cyst: swelling or lump in the wrist ... Bones, Muscles, and Joints Carpal Tunnel Syndrome Medial Epicondylitis Repetitive Stress Injuries Contact Us Print Resources Send ...

  14. Digital repetitive control under varying frequency conditions

    OpenAIRE

    Ramos Fuentes, Germán Andrés

    2012-01-01

    Premi extraordinari doctorat curs 2011-2012, àmbit d’Enginyeria Industrial The tracking/rejection of periodic signals constitutes a wide field of research in the control theory and applications area and Repetitive Control has proven to be an efficient way to face this topic; however, in some applications the period of the signal to be tracked/rejected changes in time or is uncertain, which causes and important performance degradation in the standard repetitive controller. This the...

  15. Movement planning of video and of manual aiming movements.

    Science.gov (United States)

    Bédard, Patrick; Proteau, Luc

    2005-01-01

    We studied aiming performance of adults for video- and manual aiming tasks when they had visual information about the location of the starting base or when they had not. In video-aiming, foveating the starting base and then the target prior to movement initiation (Foveation) resulted in less aiming bias and variability than when the starting base was not visible (PNV), or visible without the participants foveating it prior to movement initiation (PSV). In manual aiming, Foveation and PSV procedures resulted in identical results but reduced aiming bias and variability in comparison to the PNV procedures. The results indicate that participants had difficulty in transforming the locations of the starting base and of the target when seen on a vertical screen into an appropriate movement trajectory. Successive foveation of the starting base and of the target facilitated this transformation, resulting in direction variability being reduced by more than half in comparison to the PNV and PSV conditions. This suggests that in video-aiming the efference copy of the saccade can be used by the CNS to approximate the hand trajectory in the workspace and/or in joint coordinates (Jouffrais and Boussaoud, 1999). Hand trajectory could be readily available in manual aiming if the target location can be recoded directly in hand-coordinates as recently suggested by Buneo et al. (2002).

  16. Ictal unilateral hyperkinetic proximal lower limb movements: an independent lateralising sign suggesting ipsilateral seizure onset.

    Science.gov (United States)

    Teotónio, Rute; Rodionov, Roman; McEvoy, Andrew W; Duncan, John; Diehl, Beate; Wehner, Tim

    2013-06-01

    Our aim was to determine the lateralising value of ictal repetitive unilateral hyperkinetic proximal lower limb movements. Among 16 patients with ictal hyperkinetic features who underwent intracranial EEG between 2008 and 2011 in our centre, three had repetitive unilateral hyperkinetic proximal lower limb movements, sometimes associated with "hemiballic-like" movements of the ipsilateral upper limb. There were no other consistent lateralising signs. In all patients, these movements were ipsilateral to the ictal onset zone and started a few seconds after electroencephalographic seizure onset. In two patients, intracranial EEG showed seizure onset within the parietal lobe and mesial temporal ictal onset was recorded in a third. Two patients underwent resection and became seizure-free. Our results suggest that unilateral ictal repetitive hyperkinetic proximal lower limb movements may be an independent lateralising sign to the ipsilateral hemisphere.

  17. Responsibility and hand washing behaviour.

    Science.gov (United States)

    Taylor, Jasmine; Purdon, Christine

    2016-06-01

    Recent research suggests that compulsions persist due to a self-perpetuating mechanism of poor memory confidence and repetition. However, most of this work has examined checking compulsions and findings may not generalize well to washing compulsions. This study examined the role of responsibility in the persistence of washing behaviour. Hand washing was examined in undergraduates (n = 80) high and low in contamination fears (CF) under conditions of high or low responsibility (RL). Wash duration and number of visits to objects/locations key to the wash (e.g., soap) were examined. Overvalued responsibility predicted washing duration across groups. Neither wash duration nor number of visits was associated with memory for the wash. Wash duration predicted post-wash certainty that the wash had prevented harm, but only in the high CF group, and that effect varied according to RL: longer wash duration predicted greater certainty under conditions of low RL but predicted less certainty under conditions of high RL. Greater repetition predicted poorer sensory confidence, but only in the high CF group under high RL conditions. The data were collected in an analogue sample of modest size. Replication in a clinical sample is required. Self-perpetuating mechanisms identified in perseverative checking seem to also be present in perseverative washing, but only under conditions of high responsibility. Sensory confidence may be more important to perseverative washing than memory confidence. More research is required to understand self-perpetuating mechanisms at play when washing to under conditions of high responsibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Reduced asymmetry in motor skill learning in left-handed compared to right-handed individuals.

    Science.gov (United States)

    McGrath, Robert L; Kantak, Shailesh S

    2016-02-01

    Hemispheric specialization for motor control influences how individuals perform and adapt to goal-directed movements. In contrast to adaptation, motor skill learning involves a process wherein one learns to synthesize novel movement capabilities in absence of perturbation such that they are performed with greater accuracy, consistency and efficiency. Here, we investigated manual asymmetry in acquisition and retention of a complex motor skill that requires speed and accuracy for optimal performance in right-handed and left-handed individuals. We further determined if degree of handedness influences motor skill learning. Ten right-handed (RH) and 10 left-handed (LH) adults practiced two distinct motor skills with their dominant or nondominant arms during separate sessions two-four weeks apart. Learning was quantified by changes in the speed-accuracy tradeoff function measured at baseline and one-day retention. Manual asymmetry was evident in the RH group but not the LH group. RH group demonstrated significantly greater skill improvement for their dominant-right hand than their nondominant-left hand. In contrast, for the LH group, both dominant and nondominant hands demonstrated comparable learning. Less strongly-LH individuals (lower EHI scores) exhibited more learning of their dominant hand. These results suggest that while hemispheric specialization influences motor skill learning, these effects may be influenced by handedness.

  19. Clinical observation on modified constraint-induced movement therapy(mCIMT)and constraint-induced movement therapy (CIMT) on rehabilitation of hand function and ability of daily living in patients with stroke%改良和传统强制性运动疗法对脑卒中偏瘫患者上肢运动功能疗效的临床观察

    Institute of Scientific and Technical Information of China (English)

    刘永平; 王文清; 程子辉; 高江华; 滕晓东; 瓮长水; 毕胜

    2011-01-01

    目的 观察改良强制性运动疗法和强制性运动疗法对脑卒中偏瘫患者手功能和日常生活能力的影响.方法 选取58例符合入选标准的脑卒中偏瘫患者,随机分为改良组(27例)和强制组(31例).强制组和改良组采用限制健侧肢体动作,在治疗期间要求患者穿戴吊带和夹板,每天清醒时固定时间不少于90%,强制组每日6 h,每周训练5 d,连续2周;改良组在治疗环境中进行,每日2 h,每周3次,其它时间在日常生活活动中进行训练,连续10周.治疗前、后分别采用简易上肢机能检查量表(STEF)和Barthel指数(BI)评价患者的上肢运动功能.结果 两组患者在治疗前,STEF和Barthel指数中的10项评分差异均无统计学意义(P>0.05).经过治疗后,组内评分比较,差异均有统计学意义(P0.05),BI差异有统计学意义(P<0.01).结论 改良强制性运动疗法和强制性运动疗法可以有效提高偏瘫患者上肢的灵活性和运动速度.改良强制性运动疗法在改善日常生活活动能力方面明显优于强制性运动疗法.%Objective To study the influence of modified constraint - induced movement therapy( mCIMT ) and constraint - induced movement therapy ( CIMT ) on rehahilitation of hand function and ability of daily living in patients with stroke. Methods Fifty - eight patients with stroke were randomly divided into mCIMT group ( n =27 ) and CIMT group ( n = 31 ). The movement of unimpaired extremities in patients of CIMT group and mCIMT group had been restricted by placing them in slings for 90% waking hours in a whole day for training. Patients in CIMT treatment group were exercised for 6 h/d. 5 days a week for 2 weeks in a row. and patients in mCIMT group were exercised for 2 h/d, 3 days a week, and they were also exercised in daily living at least 2 hours every day for ten consecutive weeks. All patients in these two groups were assessed by scale of STEF( Simple Test for Evaluating Hand Function )and

  20. Implementation of specific motor expertise during a mental rotation task of hands.

    Science.gov (United States)

    Habacha, Hamdi; Molinaro, Corinne; Tabben, Montassar; Lejeune-Poutrain, Laure

    2014-11-01

    Mental rotation of the hands classically induces kinesthetic effects according to the direction of the rotation, with faster response times to the hands' medial rotations compared with lateral rotations, and is thus commonly used to induce engagement in motor imagery (MI). In the present study, we compared the performances of table tennis players (experts on hand movements), who commonly execute and observe fast hand movements, to those of soccer players (non-experts on hand movements) on a mental rotation task of hands. Our results showed a significant effect of the direction of rotation (DOR) confirming the engagement of the participants in MI. In addition, only hand movement experts were faster when the task figures corresponded to their dominant hand compared with the non-dominant hand, revealing a selective effect of motor expertise. Interestingly, the effect of the DOR collapsed in hand movement experts only when the task figures corresponded to their dominant hand, but it is noteworthy that lateral and medial rotations of the right-hand stimuli were not faster than medial rotations of the left-hand stimuli. These results are discussed in relation to possible strategies during the task. Overall, the present study highlights the embodied nature of the mental rotation task of hands by revealing selective effects of motor expertise.

  1. Coordinated Flexibility: How Initial Gaze Position Modulates Eye-Hand Coordination and Reaching

    Science.gov (United States)

    Adam, Jos J.; Buetti, Simona; Kerzel, Dirk

    2012-01-01

    Reaching to targets in space requires the coordination of eye and hand movements. In two experiments, we recorded eye and hand kinematics to examine the role of gaze position at target onset on eye-hand coordination and reaching performance. Experiment 1 showed that with eyes and hand aligned on the same peripheral start location, time lags…

  2. The Prevalence and Phenomenology of Repetitive Behavior in Genetic Syndromes

    Science.gov (United States)

    Moss, Joanna; Oliver, Chris; Arron, Kate; Burbidge, Cheryl; Berg, Katy

    2009-01-01

    We investigated the prevalence and phenomenology of repetitive behavior in genetic syndromes to detail profiles of behavior. The Repetitive Behaviour Questionnaire (RBQ) provides fine-grained identification of repetitive behaviors. The RBQ was employed to examine repetitive behavior in Angelman (N = 104), Cornelia de Lange (N = 101), Cri-du-Chat…

  3. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand ... High resolution [22.9 MB] Open Captioned [14.5 MB] Request a higher resolution file Copy the ...

  4. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... future Salt Matters: Preserving Choice, Protecting Health More Information Hand Hygiene Clean Hands Basics Send Us Feedback ... 2013 Page last updated: November 22, 2013 Content source: Centers for Disease Control and Prevention Page maintained ...

  5. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... 22.9 MB] Open Captioned [14.5 MB] Request a higher resolution file Copy the code below ... future Salt Matters: Preserving Choice, Protecting Health More Information Hand Hygiene Clean Hands Basics Send Us Feedback ...

  6. Arthritis of the Hand

    Science.gov (United States)

    .org Arthritis of the Hand Page ( 1 ) The hand and wrist have multiple small joints that work together to ... a shoelace. When the joints are affected by arthritis, activities of daily living can be difficult. Arthritis ...

  7. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... Tricky Treats Hygiene Fight Germs. Wash Your Hands! Go with the Flow Hand Hygiene Saves Lives Wash ... Wes Studi: Signs (:30) Traveler’s Health Way to Go Way to Go: Many Healthy Returns (4:00) ...

  8. Clinical application of gradient echo sequences with prolonged repetition times

    Energy Technology Data Exchange (ETDEWEB)

    Tiling, R.; Fink, U.; Deimling, M.; Bauer, W.M.; Yousry, T.; Krauss, B.

    1988-09-01

    Studies designed to optimise image contrasts of gradient echo sequences showed, that especially repetition times between 250 and 500 ms in combination with adequate echo times and flip angles provide new image contrasts. The clinical purpose of gradient echo sequences with longer TR was systematically evaluated in 450 patients. A major advantage of GE sequences was the low signal intensity of fat and bone tissue. On the other hand differnt pathologic changes showed a high signal intensity in comparison to T/sub 2/ weighted spin echo sequences as well. With the possibility of multiple slices GE sequences were of outstanding diagnostic value especially in MR of soft tissue and of the musculoskeletal system. T/sub 2/ weighted SE sequences provided no additional informations and could therefore be omitted in a great number of examinations.

  9. The Cardiopulmonary effect of passive movement

    Directory of Open Access Journals (Sweden)

    L. Loram

    2002-02-01

    Full Text Available Eleven articles were reviewed on the cardiopulmonary effects of passive movements. These included two articles on theneurological effects of passive movements. Of the eleven articles, four were considered to have level II evidence in accordance with Sackett’s rules of evidence. There was little consensus regarding the rate or duration of passive movements. There were some suggestions that upper limb movement produces a greater ventilatory response than lower limb movement. There was a statistically significant increase (p< 0.05 in minute ventilation when the movement was done at a rate of 40 repetitions per minute or more, but this change may not be clinically significant. Passive movements were not detrimental to neurosurgical patients with a normal or slightly elevated intracranial pressure, although the values of the intracranial pressure were not stated.  The studies were limited in that eight of the eleven had small sample sizes and most studies were conducted using normal subjects. Further studies with higher levels of evidence need to be  conducted to verify any results reported to date in the literature. Studies that are relevant to clinical practice also need to be conducted in populations such as sedated intensive care patients.

  10. Likelihood methods and classical burster repetition

    CERN Document Server

    Graziani, C; Graziani, Carlo; Lamb, Donald Q

    1995-01-01

    We develop a likelihood methodology which can be used to search for evidence of burst repetition in the BATSE catalog, and to study the properties of the repetition signal. We use a simplified model of burst repetition in which a number N_{\\rm r} of sources which repeat a fixed number of times N_{\\rm rep} are superposed upon a number N_{\\rm nr} of non-repeating sources. The instrument exposure is explicitly taken into account. By computing the likelihood for the data, we construct a probability distribution in parameter space that may be used to infer the probability that a repetition signal is present, and to estimate the values of the repetition parameters. The likelihood function contains contributions from all the bursts, irrespective of the size of their positional errors --- the more uncertain a burst's position is, the less constraining is its contribution. Thus this approach makes maximal use of the data, and avoids the ambiguities of sample selection associated with data cuts on error circle size. We...

  11. Hands in Systemic Disease

    Science.gov (United States)

    ... Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is ... nerves, skin and skin-related tissues, bones, and ... a systemic diseases. The hands may show changes noticed by the patient or ...

  12. Robotic hand and fingers

    Energy Technology Data Exchange (ETDEWEB)

    Salisbury, Curt Michael; Dullea, Kevin J.

    2017-06-06

    Technologies pertaining to a robotic hand are described herein. The robotic hand includes one or more fingers releasably attached to a robotic hand frame. The fingers can abduct and adduct as well as flex and tense. The fingers are releasably attached to the frame by magnets that allow for the fingers to detach from the frame when excess force is applied to the fingers.

  13. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... Matters: Preserving Choice, Protecting Health (4:30) Salt Matters: Preserving Choice, Protecting Health (2:00) Tricky Treats Hygiene Fight Germs. Wash Your Hands! Go with the Flow Hand Hygiene Saves Lives Wash Your Hands Physical Activity Knees Lifted High Making Health Easier: Active ...

  14. The hands of the projectionist.

    Science.gov (United States)

    Cartwright, Lisa

    2011-09-01

    This essay considers the work of projection and the hand of the projectionist as important components of the social space of the cinema as it comes into being in the nineteenth century and the early decades of the twentieth. I bring the concept ofMaurice Merleau-Ponty on the place of the body as an entity that applies itself to the world "like a hand to an instrument" into a discussion of the pre-cinematic projector as an instrument that we can interpret as evidence of the experience of the work of the projectionist in the spirit of film theory and media archaeology, moving work on instrumentation in a different direction from the analysis of the work of the black box in laboratory studies. Projection is described as a psychological as well as a mechanical process. It is suggested that we interpret the projector not simply in its activity as it projects films, but in its movement from site to site and in the workings of the hand of its operator behind the scenes. This account suggests a different perspective on the cinematic turn of the nineteenth century, a concept typically approached through the study of the image, the look, the camera, and the screen.

  15. An educational approach to an epidemic of repetitive motion injuries among office workers

    Energy Technology Data Exchange (ETDEWEB)

    Halunen, L.J.

    1988-09-23

    Among office workers, repetitive motion injuries such as tendonitis, muscle fatigue, and nerve irritation (caused by poor posture and arm/hand positioning while performing repetitive tasks) are a fairly new phenomenon. Office workers and their managers are not prepared to respond properly to the identification and treatment of these injuries. We found an unusually high incidence within one department at a large research facility--the Lawrence Livermore National Laboratory--and developed an educational approach to reduce the frequency and severity of these injuries. Our approach was to inform the workers and managers about the origins and severity of repetitive motion injuries and their effect on the work force. Classes in ergonomic adjustment of video workstations were scheduled for all personnel who had jobs that required heavy keyboard use. The individual's responsibility in reporting any symptoms of repetitive motion injury was emphasized. We stressed to management the seriousness of the problem, the desirability of obtaining improved equipment workers may need, or the possibility of arranging a lighter workload for those showing symptoms of repetitive motion injuries. We followed these classes and briefings with additional videotaped material and written guidelines, pamphlets, and articles for further study and discussion. Early results indicate that informed workers in a supportive environment detect symptoms earlier, and therefore recover more quickly; managers who understand the problem and are able to respond positively gain better labor relations as well as lower injury rates. 4 refs., 2 figs.

  16. Commentary : Coordination of eye and hand in time and space

    NARCIS (Netherlands)

    Bekkering, H; Sailer, U; Hyona, J; Munoz, DP; Heide, W; Radach, R

    2002-01-01

    Every day of our lives starts with a succession of actions that require eye-hand coordination. From the time we try to turn off the, alarm clock and get dressed, to putting toothpaste on the brush and preparing coffee: all these goal-directed hand movements need to be coordinated with the

  17. Visuomotor transformations for eye-hand coordination.

    Science.gov (United States)

    Henriques, D Y P; Medendorp, W P; Khan, A Z; Crawford, J D

    2002-01-01

    In recent years the scientific community has come to appreciate that the early cortical representations for visually guided arm movements are probably coded in a visual frame, i.e. relative to retinal landmarks. While this scheme accounts for many behavioral and neurophysiological observations, it also poses certain problems for manual control. For example, how are these oculocentric representations updated across eye movements, and how are they then transformed into useful commands for accurate movements of the arm relative to the body? Also, since we have two eyes, which is used as the reference point in eye-hand alignment tasks like pointing? We show that patterns of errors in human pointing suggest that early oculocentric representations for arm movement are remapped relative to the gaze direction during each saccade. To then transform these oculocentric representations into useful commands for accurate movements of the arm relative to the body, the brain correctly incorporates the three-dimensional, rotary geometry of the eyes when interpreting retinal images. We also explore the possibility that the eye-hand coordination system uses a strategy like ocular dominance, but switches alignment between the left and right eye in order to maximize eye-hand coordination in the best field of view. Finally, we describe the influence of eye position on eye-hand alignment, and then consider how head orientation influences the linkage between oculocentric visual frames and bodycentric motor frames. These findings are framed in terms of our 'conversion-on-demand' model, which suggests a virtual representation of egocentric space, i.e. one in which only those representations selected for action are put through the complex visuomotor transformations required for interaction with actual objects in personal space.

  18. Augmented robotic device for EVA hand manoeuvres

    Science.gov (United States)

    Matheson, Eloise; Brooker, Graham

    2012-12-01

    During extravehicular activities (EVAs), pressurised space suits can lead to difficulties in performing hand manoeuvres and fatigue. This is often the cause of EVAs being terminated early, or taking longer to complete. Assistive robotic gloves can be used to augment the natural motion of a human hand, meaning work can be carried out more efficiently with less stress to the astronaut. Lightweight and low profile solutions must be found in order for the assistive robotic glove to be easily integrated with a space suit pressure garment. Pneumatic muscle actuators combined with force sensors are one such solution. These actuators are extremely light, yet can output high forces using pressurised gases as the actuation drive. Their movement is omnidirectional, so when combined with a flexible exoskeleton that itself provides a degree of freedom of movement, individual fingers can be controlled during flexion and extension. This setup allows actuators and other hardware to be stored remotely on the user's body, resulting in the least possible mass being supported by the hand. Two prototype gloves have been developed at the University of Sydney; prototype I using a fibreglass exoskeleton to provide flexion force, and prototype II using torsion springs to achieve the same result. The gloves have been designed to increase the ease of human movements, rather than to add unnatural ability to the hand. A state space control algorithm has been developed to ensure that human initiated movements are recognised, and calibration methods have been implemented to accommodate the different characteristics of each wearer's hands. For this calibration technique, it was necessary to take into account the natural tremors of the human hand which may have otherwise initiated unexpected control signals. Prototype I was able to actuate the user's hand in 1 degree of freedom (DOF) from full flexion to partial extension, and prototype II actuated a user's finger in 2 DOF with forces achieved

  19. The interosseous muscles: the foundation of hand function.

    Science.gov (United States)

    Liss, Frederic E

    2012-02-01

    The interosseous muscles of the hand can be thought of as the cornerstone of hand function, as they provide a "foundation" for all intrinsic and extrinsic hand movements. Innervated by the ulnar nerve and organized in dorsal and palmar layers, these pivotal muscles have small excursion yet great impact on finger balance, grip, and pinch function, particularly when impaired by denervation and/or contracture. This article gives an overview of the functional anatomy and pathologic dysfunction of the interosseous muscles within the context of this Hand Clinics issue on the intrinsic muscular function of the hand. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. EMG-BASED SYSTEM FOR BASIC HAND MOVEMENT RECOGNITION

    Directory of Open Access Journals (Sweden)

    JHONATAN CAMACHO NAVARRO

    2012-01-01

    Full Text Available Este artículo presenta un sistema que permite identificar de forma automática, en sujetos sanos, y haciendo uso de señales electromiográficas superficiales en estado estable, los siguientes movimientos básicos de la mano: apertura, cierre, flexión, extensión, pronación y supinación, incluyendo la condición de reposo. La discriminación de los diferentes movimientos se realiza a partir de una metodología modular de reconocimiento de patrones que incluye el uso de la transformada wavelet discreta, análisis de componentes principales y máquinas de soporte vectorial. La identificación fue realizada off-line cada 256 ms mediante una interfaz hardware-software conformada por un sistema de adquisición de señales de dos canales diferenciales y algoritmos programados en Matlab® y LabVIEW®. El sistema fue entrenado y evaluado para cinco sujetos de diferente género, edad y complexión física, obteniendo tasas de acierto de hasta el 99.25 %.

  1. Freedom Now! Radical Jazz and Social Movements

    Directory of Open Access Journals (Sweden)

    Przemysław Pluciński

    2014-01-01

    Full Text Available Music is obviously not only an aesthetic phenomenon. It is embeddedin a dense network of social relations. However, its social involvementis rather ambiguous, particularly since the second half of the twentiethcentury. On the one hand, music is one of the main elements of culturalcapitalism and a part of the system of domination. On the other hand,music provokes, (coproduces or possibly strengthens and coexists witha number of counterdiscourses and social projects of counterhegemoniccharacter.The main objective of the paper is to examine relationships between both, revolutionary jazz and revolutionary social movements, namely the civil rights movement, but above all radical movements, especially black power movement. The crucial questions I am interested in are problems of selforganization, performative social practices, as well as alternatives elaborated by radical-oriented jazz circles in various social dimensions, for instance economic or symbolic.

  2. Emergent structured transition from variation to repetition in a biologically-plausible model of learning in basal ganglia.

    Directory of Open Access Journals (Sweden)

    Ashvin eShah

    2014-02-01

    Full Text Available Often, when animals encounter an unexpected sensory event, they transition from executing a variety of movements to repeating the movement(s that may have caused the event. According to a recent theory of action discovery (Redgrave and Gurney 2006, repetition allows the animal to represent those movements, and the outcome, as an action for later recruitment. The transition from variation to repetition often follows a non-random, structured, pattern. While the structure of the pattern can be explained by sophisticated cognitive mechanisms, simpler mechanisms based on dopaminergic modulation of basal ganglia (BG activity are thought to underlie action discovery (Redgrave and Gurney 2006. In this paper we ask the question: can simple BG-mediated mechanisms account for a structured transition from variation to repetition, or are more sophisticated cognitive mechanisms always necessary?To address this question, we present a computational model of BG-mediated biasing of behavior. In our model, unlike most other models of BG function, the BG biases behaviour through modulation of cortical response to excitation; many possible movements are represented by the cortical area; and excitation to the cortical area is topographically-organized. We subject the model to simple reaching tasks, inspired by behavioral studies, in which a location to which to reach must be selected. Locations within a target area elicit a reinforcement signal. A structured transition from variation to repetition emerges from simple BG-mediated biasing of cortical response to excitation. We show how the structured pattern influences behavior in simple and complicated tasks. We also present analyses that describe the structured transition from variation to repetition due to BG-mediated biasing and from biasing that would be expected from a type of cognitive biasing, allowing us to compare behaviour resulting from these types of biasing and make connections with future behavioural

  3. Static hand gesture recognition from a video

    Science.gov (United States)

    Rokade, Rajeshree S.; Doye, Dharmpal

    2011-10-01

    A sign language (also signed language) is a language which, instead of acoustically conveyed sound patterns, uses visually transmitted sign patterns to convey meaning- "simultaneously combining hand shapes, orientation and movement of the hands". Sign languages commonly develop in deaf communities, which can include interpreters, friends and families of deaf people as well as people who are deaf or hard of hearing themselves. In this paper, we proposed a novel system for recognition of static hand gestures from a video, based on Kohonen neural network. We proposed algorithm to separate out key frames, which include correct gestures from a video sequence. We segment, hand images from complex and non uniform background. Features are extracted by applying Kohonen on key frames and recognition is done.

  4. A synergy-based hand control is encoded in human motor cortical areas.

    Science.gov (United States)

    Leo, Andrea; Handjaras, Giacomo; Bianchi, Matteo; Marino, Hamal; Gabiccini, Marco; Guidi, Andrea; Scilingo, Enzo Pasquale; Pietrini, Pietro; Bicchi, Antonio; Santello, Marco; Ricciardi, Emiliano

    2016-02-15

    How the human brain controls hand movements to carry out different tasks is still debated. The concept of synergy has been proposed to indicate functional modules that may simplify the control of hand postures by simultaneously recruiting sets of muscles and joints. However, whether and to what extent synergic hand postures are encoded as such at a cortical level remains unknown. Here, we combined kinematic, electromyography, and brain activity measures obtained by functional magnetic resonance imaging while subjects performed a variety of movements towards virtual objects. Hand postural information, encoded through kinematic synergies, were represented in cortical areas devoted to hand motor control and successfully discriminated individual grasping movements, significantly outperforming alternative somatotopic or muscle-based models. Importantly, hand postural synergies were predicted by neural activation patterns within primary motor cortex. These findings support a novel cortical organization for hand movement control and open potential applications for brain-computer interfaces and neuroprostheses.

  5. Social Movements, Civil Society and Corporations

    DEFF Research Database (Denmark)

    de Bakker, Frank; Hond, Frank den; King, Brayden

    2013-01-01

    The relationships between social movements and civil society on the one hand, and the corporate world on the other hand, are often shaped by conflict over the domination of economic, cultural and social life. How this conflict plays out, in current as well as in historical times and places......, is the central question that unites the papers in this special issue. In this essay, we review the differences and points of contact between the study of social movements, civil society and corporations, and offer an agenda for future research at this intersection that also frames the papers in the special issue...

  6. When Eye Movements Express Memory for Old and New Scenes in the Absence of Awareness and Independent of Hippocampus

    Science.gov (United States)

    Smith, Christine N.; Squire, Larry R.

    2017-01-01

    Eye movements can reflect memory. For example, participants make fewer fixations and sample fewer regions when viewing old versus new scenes (the repetition effect). It is unclear whether the repetition effect requires that participants have knowledge (awareness) of the old-new status of the scenes or if it can occur independent of knowledge about…

  7. When Eye Movements Express Memory for Old and New Scenes in the Absence of Awareness and Independent of Hippocampus

    Science.gov (United States)

    Smith, Christine N.; Squire, Larry R.

    2017-01-01

    Eye movements can reflect memory. For example, participants make fewer fixations and sample fewer regions when viewing old versus new scenes (the repetition effect). It is unclear whether the repetition effect requires that participants have knowledge (awareness) of the old-new status of the scenes or if it can occur independent of knowledge about…

  8. Enhanced accuracy in novel mirror drawing after repetitive transcranial magnetic stimulation-induced proprioceptive deafferentation

    DEFF Research Database (Denmark)

    Balslev, Daniela; Christensen, Lars O.D.; Lee, Ji-hang

    2004-01-01

    a performance benefit. In this study, we tested whether deafferentation induced by repetitive transcranial magnetic stimulation (rTMS) can improve mirror tracing skills in normal subjects. Hand trajectory error during novel mirror drawing was compared across two groups of subjects that received either 1 Hz r......TMS over the somatosensory cortex contralateral to the hand or sham stimulation. Mirror tracing was more accurate after rTMS than after sham stimulation. Using a position-matching task, we confirmed that rTMS reduced proprioceptive acuity and that this reduction was largest when the coil was placed...

  9. Robotic approaches for rehabilitation of hand function after stroke.

    Science.gov (United States)

    Lum, Peter S; Godfrey, Sasha B; Brokaw, Elizabeth B; Holley, Rahsaan J; Nichols, Diane

    2012-11-01

    The goal of this review was to discuss the impairments in hand function after stroke and present previous work on robot-assisted approaches to movement neurorehabilitation. Robotic devices offer a unique training environment that may enhance outcomes beyond what is possible with conventional means. Robots apply forces to the hand, allowing completion of movements while preventing inappropriate movement patterns. Evidence from the literature is emerging that certain characteristics of the human-robot interaction are preferable. In light of this evidence, the robotic hand devices that have undergone clinical testing are reviewed, highlighting the authors' work in this area. Finally, suggestions for future work are offered. The ability to deliver therapy doses far higher than what has been previously tested is a potentially key advantage of robotic devices that needs further exploration. In particular, more efforts are needed to develop highly motivating home-based devices, which can increase access to high doses of assisted movement therapy.

  10. Longitudinal Follow-Up of Mirror Movements after Stroke: A Case Study

    Directory of Open Access Journals (Sweden)

    Hiroyuki Ohtsuka

    2015-01-01

    Full Text Available Mirror movement (MM, or visible involuntary movements of a relaxed hand during voluntary fine finger movements of an activated opposite hand, can be observed in the hand that is on the unaffected side of patients with stroke. In the present study, we longitudinally examined the relationship between voluntary movement of the affected hand and MM in the unaffected hand in a single case. We report a 73-year-old woman with a right pontine infarct and left moderate hemiparesis. MM was observed as an extension movement of the unaffected right index finger during extension movement of the affected left index finger. The affected right index movement was found to increase, while MM of the unaffected left index finger was observed to decrease with time. These results indicate that the assessment of MM might be useful for studying the process of motor recovery in patients with stroke.

  11. Human hand descriptions and gesture recognition for object manipulation.

    Science.gov (United States)

    Cobos, Salvador; Ferre, Manuel; Sánchez-Urán, M Ángel; Ortego, Javier; Aracil, Rafael

    2010-06-01

    This work focuses on obtaining realistic human hand models that are suitable for manipulation tasks. A 24 degrees of freedom (DoF) kinematic model of the human hand is defined. The model reasonably satisfies realism requirements in simulation and movement. To achieve realism, intra- and inter-finger constraints are obtained. The design of the hand model with 24 DoF is based upon a morphological, physiological and anatomical study of the human hand. The model is used to develop a gesture recognition procedure that uses principal components analysis (PCA) and discriminant functions. Two simplified hand descriptions (nine and six DoF) have been developed in accordance with the constraints obtained previously. The accuracy of the simplified models is almost 5% for the nine DoF hand description and 10% for the six DoF hand description. Finally, some criteria are defined by which to select the hand description best suited to the features of the manipulation task.

  12. Stereotypic movement disorder: easily missed.

    Science.gov (United States)

    Freeman, Roger D; Soltanifar, Atefeh; Baer, Susan

    2010-08-01

    To expand the understanding of stereotypic movement disorder (SMD) and its differentiation from tics and autistic stereotypies. Forty-two children (31 males, mean age 6y 3mo, SD 2y 8mo; 11 females, mean age 6y 7mo, SD 1y 9mo) consecutively diagnosed with SMD, without-self-injurious behavior, intellectual disability, sensory impairment, or an autistic spectrum disorder (ASD), were assessed in a neuropsychiatry clinic. A list of probe questions on the nature of the stereotypy was administered to parents (and to children if developmentally ready). Questionnaires administered included the Stereotypy Severity Scale, Short Sensory Profile, Strengths and Difficulties Questionnaire, Repetitive Behavior Scale--Revised, and the Developmental Coordination Disorder Questionnaire. The stereotyped movement patterns were directly observed and in some cases further documented by video recordings made by parents. The probe questions were used again on follow-up at a mean age of 10 years 7 months (SD 4y 4mo). Mean age at onset was 17 months. Males exceeded females by 3:1. Family history of a pattern of SMD was reported in 13 and neuropsychiatric comorbidity in 30 (attention-deficit-hyperactivity disorder in 16, tics in 18, and developmental coordination disorder in 16). Obsessive-compulsive disorder occurred in only two. The Short Sensory Profile correlated with comorbidity (p<0.001), the Stereotypy Severity Scale (p=0.009), and the Repetitive Behavior Scale (p<0.001); the last correlated with the Stereotypy Severity Scale (p=0.001). Children (but not their parents) liked their movements, which were usually associated with excitement or imaginative play. Mean length of follow-up was 4 years 8 months (SD 2y 10mo). Of the 39 children followed for longer than 6 months, the behavior stopped or was gradually shaped so as to occur primarily privately in 25. Misdiagnosis was common: 26 were initially referred as tics, 10 as ASD, five as compulsions, and one as epilepsy. Co-occurring facial

  13. Telerehabilitation approach for patients with hand impairment.

    Science.gov (United States)

    Staszuk, Arleta; Wiatrak, Benita; Tadeusiewicz, Ryszard; Karuga-Kuźniewska, Ewa; Rybak, Zbigniew

    2016-01-01

    Telerehabilitation is one of the newest branches of telemedicine which has been developed because patients need regular trainings outside the medical institution but still under specialist supervision. It helps maintain regularity of exercises and reduces costs. The professional and advanced systems for telerehabilitation are presented in papers, however, there is still lack of development of minor systems which provide therapeutic values and are more accessible to people. Therefore we focus on a solution for hand telerehabilitation of poststroke patients, based solely on a personal computer and camera. We focused on the manipulative hand (fingers, metacarpus, wrist) movements trainings for patients with cerebral palsy. The contact between patient and physiotherapist is provided by using web cameras and web service. Additionally, the camera can be used to monitor the effectiveness of performed exercises. Computer vision system keeps track of the patient's hand movement. The digital image processing is used to detect if the patient performs exercises correctly. We created web service and software application TeleReh that provides therapeutic values for the hand impaired people. The system created was evaluated by three physiotherapists, one doctor and a cerebral palsy patient. Our solution applies to all patients who have undergone basic rehabilitation in hospital and need to continue hand rehabilitation at home. The main advantages are: easy adaptation to the individual needs and abilities, monitoring the progress by using automatically generated reports after each training session. It is worth noticing that discussion between IT specialists, rehabilitants and patients was necessary to achieve good results.

  14. Rethinking optimal control of human movements

    OpenAIRE

    Huh, Dongsung

    2012-01-01

    The complex bio-mechanics of human body is capable of generating an unlimited repertoire of movements, which on one hand yields highly versatile motor behavior but on the other hand presents a formidable control problem for the brain. Understanding the computational process that allows us to easily perform various motor tasks with a high degree of coordination is of central interest to both neuroscience and robotics control. In recent decades, it became widely accepted that the observed movem...

  15. Fingertip Detection for Hand Pose Recognition

    Directory of Open Access Journals (Sweden)

    M.K. Bhuyan

    2012-03-01

    Full Text Available In this paper, a novel algorithm is proposed for fingertip detection and finger type recognition. The algorithm is applied for locating fingertips in hand region extracted by Bayesian rule based skincolor segmentation. Morphological operations are performed in the segmented hand region by observing key geometric features. A probabilistic modeling of the geometric features of finger movement has made the finger type recognition process significantly robust. Proposed method can be employed in a variety of applications like sign language recognition and human robot interactions.

  16. Gaze anchoring to a pointing target is present during the entire pointing movement and is driven by a non-visual signal

    NARCIS (Netherlands)

    Neggers, SFW; Bekkering, H

    2001-01-01

    A well-coordinated pattern of eye and hand movements can be observed during goal-directed arm movements. Typically, a saccadic eye movement precedes the arm movement, and its occurrence is temporally correlated with the start of the arm movement. Furthermore, the coupling of gaze and aiming movement

  17. The neurobiology of repetitive behavior : of mice…

    NARCIS (Netherlands)

    Langen, Marieke; Kas, Martien J H; Staal, Wouter G; van Engeland, Herman; Durston, Sarah

    2011-01-01

    Repetitive and stereotyped behavior is a prominent element of both animal and human behavior. Similar behavior is seen across species, in diverse neuropsychiatric disorders and in key phases of typical development. This raises the question whether these similar classes of behavior are caused by simi

  18. Large-scale detection of repetitions.

    Science.gov (United States)

    Smyth, W F

    2014-05-28

    Combinatorics on words began more than a century ago with a demonstration that an infinitely long string with no repetitions could be constructed on an alphabet of only three letters. Computing all the repetitions (such as ∙∙∙TTT ∙∙∙ or ∙∙∙ CGACGA ∙∙∙ ) in a given string x of length n is one of the oldest and most important problems of computational stringology, requiring time in the worst case. About a dozen years ago, it was discovered that repetitions can be computed as a by-product of the Θ(n)-time computation of all the maximal periodicities or runs in x. However, even though the computation is linear, it is also brute force: global data structures, such as the suffix array, the longest common prefix array and the Lempel-Ziv factorization, need to be computed in a preprocessing phase. Furthermore, all of this effort is required despite the fact that the expected number of runs in a string is generally a small fraction of the string length. In this paper, I explore the possibility that repetitions (perhaps also other regularities in strings) can be computed in a manner commensurate with the size of the output.

  19. Verbal Repetitions and Echolalia in Alzheimer's Discourse

    Science.gov (United States)

    Da Cruz, Fernanda Miranda

    2010-01-01

    This article reports on an investigation of echolalic repetition in Alzheimer's disease (AD). A qualitative analysis of data from spontaneous conversations with MHI, a woman with AD, is presented. The data come from the DALI Corpus, a corpus of spontaneous conversations involving subjects with AD. This study argues that echolalic effects can be…

  20. Neurobehavioural Correlates of Abnormal Repetitive Behaviour

    Directory of Open Access Journals (Sweden)

    R. A. Ford

    1991-01-01

    Full Text Available Conditions in which echolalia and echopraxia occur are reviewed, followed by an attempt to elicit possible mechanisms of these phenomena. A brief description of stereotypical and perseverative behaviour and obsessional phenomena is given. It is suggested that abnormal repetitive behaviour may occur partly as a result of central dopaminergic dysfunction.

  1. Reducing Repetitive Speech: Effects of Strategy Instruction.

    Science.gov (United States)

    Dipipi, Caroline M.; Jitendra, Asha K.; Miller, Judith A.

    2001-01-01

    This article describes an intervention with an 18-year-old young woman with mild mental retardation and a seizure disorder, which focused on her repetitive echolalic verbalizations. The intervention included time delay, differential reinforcement of other behaviors, and self-monitoring. Overall, the intervention was successful in facilitating…

  2. Verbal Repetitions and Echolalia in Alzheimer's Discourse

    Science.gov (United States)

    Da Cruz, Fernanda Miranda

    2010-01-01

    This article reports on an investigation of echolalic repetition in Alzheimer's disease (AD). A qualitative analysis of data from spontaneous conversations with MHI, a woman with AD, is presented. The data come from the DALI Corpus, a corpus of spontaneous conversations involving subjects with AD. This study argues that echolalic effects can be…

  3. Hand eczema classification

    DEFF Research Database (Denmark)

    Diepgen, T L; Andersen, Klaus Ejner; Brandao, F M;

    2008-01-01

    Summary Background Hand eczema is a long-lasting disease with a high prevalence in the background population. The disease has severe, negative effects on quality of life and sometimes on social status. Epidemiological studies have identified risk factors for onset and prognosis, but treatment...... of the disease is rarely evidence based, and a classification system for different subdiagnoses of hand eczema is not agreed upon. Randomized controlled trials investigating the treatment of hand eczema are called for. For this, as well as for clinical purposes, a generally accepted classification system...... for hand eczema is needed. Objectives The present study attempts to characterize subdiagnoses of hand eczema with respect to basic demographics, medical history and morphology. Methods Clinical data from 416 patients with hand eczema from 10 European patch test clinics were assessed. Results...

  4. THE INFLUENCE OF LOWER LIMB MOVEMENT ON UPPER LIMB MOVEMENT SYMMETRY WHILE SWIMMING THE BREASTSTROKE

    Directory of Open Access Journals (Sweden)

    M. Jaszczak

    2011-09-01

    Full Text Available This study 1 examined the influence of lower limb movement on upper limb movement symmetry, 2 determined the part of the propulsion phase displaying the greatest hand movement asymmetry, 3 diagnosed the range of upper limb propulsion phase which is the most prone to the influence of the lower limbs while swimming the breaststroke. Twenty-four participants took part in two tests. Half of them performed an asymmetrical leg movement. The propulsion in the first test was generated by four limbs while in the second one only by the upper limbs. The pressure differentials exerted by the water on the back and on the palm of the right and left hand were measured. Then, the asymmetry coefficient of the hand movement was determined. No changes in the level of the asymmetry index in participants performing correct (symmetrical lower limb movement were observed. Incorrect (asymmetrical leg motion resulted in an increase of hand asymmetry. It could be concluded that lower limb faults neutralize upper limb performance when swimming on a rectilinear path. However, most asymmetrical arm performance should be identified with the conversion of propulsion into recovery. Nevertheless, its proneness to influence improper leg performance might be expected at the beginning of arm propulsion.

  5. Hand deburring guide

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.K.

    1979-07-01

    Appropriate hand deburring techniques have always been difficult to define because of the infinite variety of part shapes, sizes, materials, and burr conditions. This guide, however, has been prepared to assist those responsible for hand deburring. The purpose of the guide is to define Bendix Kansas City burr specifications and inspection practices; to define the results of practical tests on hand deburring; to define some typical in-house practices; and to define the in-house tools available for this work.

  6. 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.

  7. Hand Hygiene: An Update.

    Science.gov (United States)

    Bolon, Maureen K

    2016-09-01

    The medical field has long recognized the importance of hand hygiene in preventing health care-associated infections, yet studies indicate that this important task is performed only 40% of the time. Health care workers cite several barriers to optimal performance of hand hygiene, but the time required to perform this task is foremost among them. Introduction of alcohol-based hand rubs, bundled interventions, and incorporation of technologies designed to monitor and promote hand hygiene all represent promising advances in this field. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. [Optimizing surgical hand disinfection].

    Science.gov (United States)

    Kampf, G; Kramer, A; Rotter, M; Widmer, A

    2006-08-01

    For more than 110 years hands of surgeons have been treated before a surgical procedure in order to reduce the bacterial density. The kind and duration of treatment, however, has changed significantly over time. Recent scientific evidence suggests a few changes with the aim to optimize both the efficacy and the dermal tolerance. Aim of this article is the presentation and discussion of new insights in surgical hand disinfection. A hand wash should be performed before the first disinfection of a day, ideally at least 10 min before the beginning of the disinfection as it has been shown that a 1 min hand wash significantly increases skin hydration for up to 10 min. The application time may be as short as 1.5 min depending on the type of hand rub. Hands and forearms should be kept wet with the hand rub for the recommended application time in any case. A specific rub-in procedure according to EN 12791 has been found to be suitable in order to avoid untreated skin areas. The alcohol-based hand rub should have a proven excellent dermal tolerance in order to ensure appropriate compliance. Considering these elements in clinical practice can have a significant impact to optimize the high quality of surgical hand disinfection for prevention of surgical site infections.

  9. Movement Data Anonymity through Generalization

    Directory of Open Access Journals (Sweden)

    Anna Monreale

    2010-08-01

    Full Text Available Wireless networks and mobile devices, such as mobile phones and GPS receivers, sense and track the movements of people and vehicles, producing society-wide mobility databases. This is a challenging scenario for data analysis and mining. On the one hand, exciting opportunities arise out of discovering new knowledge about human mobile behavior, and thus fuel intelligent info-mobility applications. On other hand, new privacy concerns arise when mobility data are published. The risk is particularly high for GPS trajectories, which represent movement of a very high precision and spatio-temporal resolution: the de-identification of such trajectories (i.e., forgetting the ID of their associated owners is only a weak protection, as generally it is possible to re-identify a person by observing her routine movements. In this paper we propose a method for achieving true anonymity in a dataset of published trajectories, by defining a transformation of the original GPS trajectories based on spatial generalization and k-anonymity. The proposed method offers a formal data protection safeguard, quantified as a theoretical upper bound to the probability of re-identification. We conduct a thorough study on a real-life GPS trajectory dataset, and provide strong empirical evidence that the proposed anonymity techniques achieve the conflicting goals of data utility and data privacy. In practice, the achieved anonymity protection is much stronger than the theoretical worst case, while the quality of the cluster analysis on the trajectory data is preserved.

  10. A moving robotic hand system for whole-glove permeation and penetration: captan and nitrile gloves.

    Science.gov (United States)

    Phalen, Robert; Hee, Shane Que

    2008-04-01

    The aim of this study was to develop a robotic hand to test the influence of hand movement on the permeation/penetration of captan through disposable nitrile rubber gloves. An available robotic hand was modified to within one standard deviation of the anthropometric 50th percentile male hand. Permeation tests used a nylon inspection glove interposed between medium-size outer and inner nitrile gloves, the latter protected the hand. Permeation of an aqueous emulsion (217 mg/mL) of captan was conducted at 35 degrees C +/- 0.7 degrees C. A new surface wipe technique facilitated collection of captan from the inner surface of the exposed nitrile gloves, a technique favored above rinse methods that extracted captan from within the glove. With hand movement, the permeated mass of captan collected after 8 hr ranged from 1.6 to 970 microg (Brand A) and 8.6 +/- 1.2 microg (Brand B). Without hand movement, the corresponding masses ranged from 1.4 to 8.4 microg (Brand A) and 11 +/- 3 mg (Brand B). These results were not significantly different at p captan with no movement. Hand movement did not appear to significantly affect the permeation of captan through nitrile gloves. However, hand movement did influence physical and/or chemical degradation, resulting in glove failures. The robotic hand simulated normal hand motions, was reliable, and could be used to assess the influence of hand movement on the permeation of nonvolatile components through gloves. Future research should continue to investigate the influence of hand movement and additional work factors on the permeation, penetration, and physical integrity of protective gloves.

  11. Anticipatory Eye Movements in Congkak

    Directory of Open Access Journals (Sweden)

    Sheryl Chong

    2011-05-01

    Full Text Available Congkak is a traditional Malaysian board game involving two players taking turns to pick up marbles from a series of holes on the board. We used this game as a model to explore the role of anticipatory eye movements during natural actions (in this case serially picking up/putting marbles as novices learnt the game. Prior work on eye and hand movements in natural behaviour shows that much of the demand on the visual system is computed at the moment it is needed and doesn't depend on information acquired from previous fixations. Vision is driven by the task demands. However, anticipatory fixations to upcoming targets of manipulation have recently been shown to confer spatial accuracy and influence the eye-hand latency. We find that experience with the game also influences the deployment of these anticipatory “look-ahead” fixations, and that their influence on eye-hand latency varies with experience. Results suggest that as our experience in Congkak grows, so does our knowledge of the space relationships necessary for task success.

  12. [Hand surgery training].

    Science.gov (United States)

    Moutet, F; Haloua, J P

    2003-10-01

    Training of the hand surgeon HAND SURGEON A CONCEPT: The hand surgeon is supposed to be in charge of all the hand lesions regarding, skeleton, muscles, tendons, nerves and vessels. He has to be able to insure reparation and coverage of all of them. So he is involved in all the structures, which insure integrity and function of the hand. PURPOSE AND WAYS OF TRAINING: To obtain the asked ability, the hand surgeon training has to be global and sustained by two underlying surgical specialities: orthopedic surgery and plastic and reconstructive surgery. From 2000 after many years of dealings, a Right to the Title in Hand Surgery was born. This Right to the Title wants to be the formal recognition of the specific training of the hand surgeon. For the well-recognized ancient hand surgeons they need to be confirmed by one's peers. Now a day the hand surgeon has to satisfy to this specific training: Passed the complete training and exam of the Orthopedic or Plastic surgery board. Spent at least 6 months as resident in the other underlying specialty. Passed a microsurgery examination. Passed one of the four national Hand Surgery diplomas (DIU/Inter-Universitary Diploma). The examinations have been harmonized. A common formation is delivered regarding hand surgery, the way of examination is the same and the formation is 2 years long. The final exam is presented in front of board of examiners where a teacher of one of the other three national diplomas is present. Spent at least 2 years in a formative hand surgery unit, listed by the French College of Hand Surgeons, as senior surgeon. Those requirements are heavy to assume and need a heavy personal involvement. That seems to be necessary to have an ability level as high as possible. Emergency surgery practice is absolutely necessary in this training. All the 17 university formative hand surgery units listed by the French College of Hand Surgeons are members of the FESUM (European Federation of the Emergency Hand Units

  13. Effects of low-frequency repetitive transcranial magnetic stimulation and neuromuscular electrical stimulation on upper extremity motor recovery in the early period after stroke: a preliminary study.

    Science.gov (United States)

    Tosun, Aliye; Türe, Sabiha; Askin, Ayhan; Yardimci, Engin Ugur; Demirdal, Secil Umit; Kurt Incesu, Tülay; Tosun, Ozgur; Kocyigit, Hikmet; Akhan, Galip; Gelal, Fazıl Mustafa

    2017-07-01

    To assess the efficacy of inhibitory repetitive transcranial magnetic stimulation (rTMS) and neuromuscular electrical stimulation (NMES) on upper extremity motor function in patients with acute/subacute ischemic stroke. Twenty-five ischemic acute/subacute stroke subjects were enrolled in this randomized controlled trial. Experimental group 1 received low frequency (LF) rTMS to the primary motor cortex of the unaffected side + physical therapy (PT) including activities to improve strength, flexibility, transfers, posture, balance, coordination, and activities of daily living, mainly focusing on upper limb movements; experimental group 2 received the same protocol combined with NMES to hand extensor muscles; and the control group received only PT. Functional magnetic resonance imaging (fMRI) scan was used to evaluate the activation or inhibition of the affected and unaffected primary motor cortex. No adverse effect was reported. Most of the clinical outcome scores improved significantly in all groups, however no statistically significant difference was found between groups due to the small sample sizes. The highest percent improvement scores were observed in TMS + NMES group (varying between 48 and 99.3%) and the lowest scores in control group (varying between 13.1 and 28.1%). Hand motor recovery was significant in both experimental groups while it did not change in control group. Some motor cortex excitability changes were also observed in fMRI. LF-rTMS with or without NMES seems to facilitate the motor recovery in the paretic hand of patients with acute/subacute ischemic stroke. TMS or the combination of TMS + NMES may be a promising additional therapy in upper limb motor training. Further studies with larger numbers of patients are needed to establish their effectiveness in upper limb motor rehabilitation of stroke.

  14. Complementary Hand Responses Occur in Both Peri- and Extrapersonal Space.

    Directory of Open Access Journals (Sweden)

    Tim W Faber

    Full Text Available Human beings have a strong tendency to imitate. Evidence from motor priming paradigms suggests that people automatically tend to imitate observed actions such as hand gestures by performing mirror-congruent movements (e.g., lifting one's right finger upon observing a left finger movement; from a mirror perspective. Many observed actions however, do not require mirror-congruent responses but afford complementary (fitting responses instead (e.g., handing over a cup; shaking hands. Crucially, whereas mirror-congruent responses don't require physical interaction with another person, complementary actions often do. Given that most experiments studying motor priming have used stimuli devoid of contextual information, this space or interaction-dependency of complementary responses has not yet been assessed. To address this issue, we let participants perform a task in which they had to mirror or complement a hand gesture (fist or open hand performed by an actor depicted either within or outside of reach. In three studies, we observed faster reaction times and less response errors for complementary relative to mirrored hand movements in response to open hand gestures (i.e., 'hand-shaking' irrespective of the perceived interpersonal distance of the actor. This complementary effect could not be accounted for by a low-level spatial cueing effect. These results demonstrate that humans have a strong and automatic tendency to respond by performing complementary actions. In addition, our findings underline the limitations of manipulations of space in modulating effects of motor priming and the perception of affordances.

  15. Hand Rehabilitation Learning System With an Exoskeleton Robotic Glove.

    Science.gov (United States)

    Ma, Zhou; Ben-Tzvi, Pinhas; Danoff, Jerome

    2016-12-01

    This paper presents a hand rehabilitation learning system, the SAFE Glove, a device that can be utilized to enhance the rehabilitation of subjects with disabilities. This system is able to learn fingertip motion and force for grasping different objects and then record and analyze the common movements of hand function including grip and release patterns. The glove is then able to reproduce these movement patterns in playback fashion to assist a weakened hand to accomplish these movements, or to modulate the assistive level based on the user's or therapist's intent for the purpose of hand rehabilitation therapy. Preliminary data have been collected from healthy hands. To demonstrate the glove's ability to manipulate the hand, the glove has been fitted on a wooden hand and the grasping of various objects was performed. To further prove that hands can be safely driven by this haptic mechanism, force sensor readings placed between each finger and the mechanism are plotted. These experimental results demonstrate the potential of the proposed system in rehabilitation therapy.

  16. Wash Your Hands

    Science.gov (United States)

    ... don't have soap and clean, running water? Washing hands with soap and water is the best way to get rid of germs in most situations. If soap and water are not available, use an alcohol-based hand sanitizer [423 KB] that contains at least 60% alcohol. ...

  17. Pneumatically actuated hand tool

    NARCIS (Netherlands)

    Cool, J.C.; Rijnsaardt, K.A.

    1996-01-01

    Abstract of NL 9401195 (A) Pneumatically actuated hand tool for carrying out a mechanical operation, provided with an exchangeable gas cartridge in which the gas which is required for pneumatic actuation is stored. More particularly, the hand tool is provided with at least one pneumatic motor, at

  18. HAND INJURIES IN VOLLEYBALL

    NARCIS (Netherlands)

    BHAIRO, NH; NIJSTEN, MWN; VANDALEN, KC; TENDUIS, HJ

    We studied the long-term sequelae of hand injuries as a result of playing volleyball. In a retrospective study, 226 patients with injuries of the hand who were seen over a 5-year period at our Trauma Department, were investigated. Females accounted for 66 % of all injuries. The mean age was 26

  19. Hand measuring eqipment

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This note is used in connection with a 3 x 2 hours laboratory exercise as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The laboratory includes a demonstration of a series of hand measuring tools as well as a number of exercises, illustrating the use of hand measuring equipment...

  20. HAND INJURIES IN VOLLEYBALL

    NARCIS (Netherlands)

    BHAIRO, NH; NIJSTEN, MWN; VANDALEN, KC; TENDUIS, HJ

    1992-01-01

    We studied the long-term sequelae of hand injuries as a result of playing volleyball. In a retrospective study, 226 patients with injuries of the hand who were seen over a 5-year period at our Trauma Department, were investigated. Females accounted for 66 % of all injuries. The mean age was 26 years

  1. Hand Hygiene: When and How

    Science.gov (United States)

    ... handrub? How to handwash? RUB HANDS FOR HAND HYGIENE! WASH HANDS WHEN VISIBLY SOILED Duration of the entire procedure: ... from its use. When? YOUR 5 MOMENTS FOR HAND HYGIENE 1 BEFORETOUCHINGA PATIENT 2 B P ECFLOER R ...

  2. Robotic training and kinematic analysis of arm and hand after incomplete spinal cord injury: a case study.

    Science.gov (United States)

    Kadivar, Z; Sullivan, J L; Eng, D P; Pehlivan, A U; O'Malley, M K; Yozbatiran, N; Francisco, G E

    2011-01-01

    Regaining upper extremity function is the primary concern of persons with tetraplegia caused by spinal cord injury (SCI). Robotic rehabilitation has been inadequately tested and underutilized in rehabilitation of the upper extremity in the SCI population. Given the acceptance of robotic training in stroke rehabilitation and SCI gait training, coupled with recent evidence that the spinal cord, like the brain, demonstrates plasticity that can be catalyzed by repetitive movement training such as that available with robotic devices, it is probable that robotic upper-extremity training of persons with SCI could be clinically beneficial. The primary goal of this pilot study was to test the feasibility of using a novel robotic device for the upper extremity (RiceWrist) and to evaluate robotic rehabilitation using the RiceWrist in a tetraplegic person with incomplete SCI. A 24-year-old male with incomplete SCI participated in 10 sessions of robot-assisted therapy involving intensive upper limb training. The subject successfully completed all training sessions and showed improvements in movement smoothness, as well as in the hand function. Results from this study provide valuable information for further developments of robotic devices for upper limb rehabilitation in persons with SCI. © 2011 IEEE

  3. Regular use of a hand cream can attenuate skin dryness and roughness caused by frequent hand washing

    Directory of Open Access Journals (Sweden)

    Kampf Günter

    2006-02-01

    Full Text Available Abstract Background Aim of the study was to determine the effect of the regular use of a hand cream after washing hands on skin hydration and skin roughness. Methods Twenty-five subjects washed hands and forearms with a neutral soap four times per day, for 2 minutes each time, for a total of two weeks. One part of them used a hand cream after each hand wash, the others did not (cross over design after a wash out period of two weeks. Skin roughness and skin hydration were determined on the forearms on days 2, 7, 9 and 14. For skin roughness, twelve silicon imprint per subject and time point were taken from the stratum corneum and assessed with a 3D skin analyzer for depth of the skin relief. For skin hydration, five measurements per subject and time point were taken with a corneometer. Results Washing hands lead to a gradual increase of skin roughness from 100 (baseline to a maximum of 108.5 after 9 days. Use of a hand cream after each hand wash entailed a decrease of skin roughness which the lowest means after 2 (94.5 and 14 days (94.8. Skin hydration was gradually decreased after washing hands from 79 (baseline to 65.5 after 14 days. The hand wash, followed by use of a hand cream, still decreased skin hydration after 2 days (76.1. Over the next 12 days, however, skin hydration did not change significantly (75.6 after 14 days. Conclusion Repetitive and frequent hand washing increases skin dryness and roughness. Use of a hand cream immediately after each hand wash can confine both skin dryness and skin roughness. Regular use of skin care preparations should therefore help to prevent both dry and rough skin among healthcare workers in clinical practice.

  4. Finger tips detection for two handed gesture recognition

    Science.gov (United States)

    Bhuyan, M. K.; Kar, Mithun Kumar; Neog, Debanga Raj

    2011-10-01

    In this paper, a novel algorithm is proposed for fingertips detection in view of two-handed static hand pose recognition. In our method, finger tips of both hands are detected after detecting hand regions by skin color-based segmentation. At first, the face is removed in the image by using Haar classifier and subsequently, the regions corresponding to the gesturing hands are isolated by a region labeling technique. Next, the key geometric features characterizing gesturing hands are extracted for two hands. Finally, for all possible/allowable finger movements, a probabilistic model is developed for pose recognition. Proposed method can be employed in a variety of applications like sign language recognition and human-robot-interactions etc.

  5. Creative movement as a holistic teaching approach in primary school

    OpenAIRE

    Geršak, Vesna

    2016-01-01

    Creative movement is an active approach to teaching, using the body to learn numerous topics. It can be defined as an approach in which children use movement to express, form and create a variety of learning content in a range of school subjects. When talking about creative movement as an approach to teaching subjects on the school curriculum, the focus rests firmly on the following two areas: movement, on the one hand, and arts concepts, on the other. When implementing creative movement in t...

  6. Movement disorders and sleep.

    Science.gov (United States)

    Driver-Dunckley, Erika D; Adler, Charles H

    2012-11-01

    This article summarizes what is currently known about sleep disturbances in several movement disorders including Parkinson disease, essential tremor, parkinsonism, dystonia, Huntington disease, myoclonus, and ataxias. There is an association between movement disorders and sleep. In some cases the prevalence of sleep disorders is much higher in patients with movement disorder, such as rapid eye movement sleep behavior disorder in Parkinson disease. In other cases, sleep difficulties worsen the involuntary movements. In many cases the medications used to treat patients with movement disorder disturb sleep or cause daytime sleepiness. The importance of discussing sleep issues in patients with movement disorders cannot be underestimated.

  7. Illumination-invariant hand gesture recognition

    Science.gov (United States)

    Mendoza-Morales, América I.; Miramontes-Jaramillo, Daniel; Kober, Vitaly

    2015-09-01

    In recent years, human-computer interaction (HCI) has received a lot of interest in industry and science because it provides new ways to interact with modern devices through voice, body, and facial/hand gestures. The application range of the HCI is from easy control of home appliances to entertainment. Hand gesture recognition is a particularly interesting problem because the shape and movement of hands usually are complex and flexible to be able to codify many different signs. In this work we propose a three step algorithm: first, detection of hands in the current frame is carried out; second, hand tracking across the video sequence is performed; finally, robust recognition of gestures across subsequent frames is made. Recognition rate highly depends on non-uniform illumination of the scene and occlusion of hands. In order to overcome these issues we use two Microsoft Kinect devices utilizing combined information from RGB and infrared sensors. The algorithm performance is tested in terms of recognition rate and processing time.

  8. iHand: an interactive bare-hand-based augmented reality interface on commercial mobile phones

    Science.gov (United States)

    Choi, Junyeong; Park, Jungsik; Park, Hanhoon; Park, Jong-Il

    2013-02-01

    The performance of mobile phones has rapidly improved, and they are emerging as a powerful platform. In many vision-based applications, human hands play a key role in natural interaction. However, relatively little attention has been paid to the interaction between human hands and the mobile phone. Thus, we propose a vision- and hand gesture-based interface in which the user holds a mobile phone in one hand but sees the other hand's palm through a built-in camera. The virtual contents are faithfully rendered on the user's palm through palm pose estimation, and reaction with hand and finger movements is achieved that is recognized by hand shape recognition. Since the proposed interface is based on hand gestures familiar to humans and does not require any additional sensors or markers, the user can freely interact with virtual contents anytime and anywhere without any training. We demonstrate that the proposed interface works at over 15 fps on a commercial mobile phone with a 1.2-GHz dual core processor and 1 GB RAM.

  9. Development of Artificial Hand Gripper by using Microcontroller

    Directory of Open Access Journals (Sweden)

    A. M. Mohd Ali

    2011-12-01

    Full Text Available This paper focuses on the development of a measurement hand gripper to help handicap patient due to accident and diseases. Basically, when the patient needed to perform exercises they must get an appointment with a doctor. Normally this will take few weeks or months. This is because the rehabilitation devices at Physiotherapy Department in hospital are very limited. From this problem, we suggest to develop a reasonably cheap home-based rehabilitation measurement devices which can perform the task of assisting paralyze patient at home. The basic movement of the patient was limited from a wrist, elbow and shoulder. The development of this project involves the designing of a sensors equipped Smart Glove and a measurement hand gripper device. The hand gripper device will move based on a human operator’s finger movement using the Smart Glove. The purpose of our project is to design and develop a master-slave system robotic hand which can be a substitution for the paralyzed hand in therapy to aid in recovery process of patients upper limb function. The project involves an Arduino microcontroller for the instrumentation, communication and controlling applications. A series of flex sensors are fitted in a master glove to get readings from the movement of human fingers. Microcontroller will further use this information to control multiple servos that controls the movement of slave robotic hand.

  10. A repetitive elements perspective in Polycomb epigenetics.

    Directory of Open Access Journals (Sweden)

    Valentina eCasa

    2012-10-01

    Full Text Available Repetitive elements comprise over two-thirds of the human genome. For a long time, these elements have received little attention since they were considered non functional. On the contrary, recent evidence indicates that they play central roles in genome integrity, gene expression and disease. Indeed, repeats display meiotic instability associated with disease and are located within common fragile sites, which are hotspots of chromosome rearrangements in tumors. Moreover, a variety of diseases have been associated with aberrant transcription of repetitive elements. Overall this indicates that appropriate regulation of repetitive elements’ activity is fundamental.Polycomb group (PcG proteins are epigenetic regulators that are essential for the normal development of multicellular organisms. Mammalian PcG proteins are involved in fundamental processes, such as cellular memory, cell proliferation, genomic imprinting, X-inactivation, and cancer development. PcG proteins can convey their activity through long-distance interactions also on different chromosomes. This indicates that the 3D organization of PcG proteins contributes significantly to their function. However, it is still unclear how these complex mechanisms are orchestrated and which role PcG proteins play in the multi-level organization of gene regulation. Intriguingly, the greatest proportion of Polycomb-mediated chromatin modifications is located in genomic repeats and it has been suggested that they could provide a binding platform for Polycomb proteins.Here, these lines of evidence are woven together to discuss how repetitive elements could contribute to chromatin organization in the 3D nuclear space.

  11. Emotional arousal enhances word repetition priming

    OpenAIRE

    Thomas, Laura A.; LaBar, Kevin S.

    2005-01-01

    Three experiments were conducted to determine if emotional content increases repetition priming magnitude. In the study phase of Experiment 1, participants rated high-arousing negative (taboo) words and neutral words for concreteness. In the test phase, they made lexical decision judgements for the studied words intermixed with novel words (half taboo, half neutral) and pseudowords. In Experiment 2, low-arousing negative (LAN) words were substituted for the taboo words, and in Experiment 3 al...

  12. The Rhythms of Echo. Variations on Repetition

    Directory of Open Access Journals (Sweden)

    Rosa María Aradra Sánchez

    2015-04-01

    Full Text Available This paper presents a study on the echo as metric and rhetorical procedure. It makes a brief tour through some of the poetic manifestations of echo in the Spanish literary tradition, and a brief tour through the attention that metric theory has paid to this phenomenon. Then it stops at the possibilities that rhetoric offers for its analysis from the generic approach of the discursive repetition phenomena.

  13. Active Appearance Model Based Hand Gesture Recognition

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper addresses the application of hand gesture recognition in monocular image sequences using Active Appearance Model (AAM). For this work, the proposed algorithm is conposed of constructing AAMs and fitting the models to the interest region. In training stage, according to the manual labeled feature points, the relative AAM is constructed and the corresponding average feature is obtained. In recognition stage, the interesting hand gesture region is firstly segmented by skin and movement cues.Secondly, the models are fitted to the image that includes the hand gesture, and the relative features are extracted.Thirdly, the classification is done by comparing the extracted features and average features. 30 different gestures of Chinese sign language are applied for testing the effectiveness of the method. The Experimental results are given indicating good performance of the algorithm.

  14. Posterior alien hand syndrome: case report

    Energy Technology Data Exchange (ETDEWEB)

    Rohde, S.; Weidauer, S.; Lanfermann, H.; Zanella, F. [Institute of Neuroradiology, Johann Wolfgang Goethe University, Schleusenweg 2-16, 60528 Frankfurt am Main (Germany)

    2002-11-01

    The alien hand syndrome (AHS) is involuntary uncontrolled movement of an arm with a sense of estrangement from the limb itself. AHS was initially used to describe interhemispheric disconnection phenomena in patients with lesions in the anterior corpus callosum, but it has been found in patients with posterior cerebral lesions without involvement of the corpus callosum, for example parietal infarcts or corticobasal degeneration. The posterior alien hand syndrome is less frequent and presents with nonpurposive behaviour like lifting the arm or writhing fingers. We report an 80-year-old woman with a posterior AHS of the dominant right hand. MRI showed atrophy of the pre- and postcentral gyri without involvement of the corpus callosum. We discuss the aetiology of the posterior AHS and the differences from the anterior varieties. (orig.)

  15. Hand in motion reveals mind in motion

    Directory of Open Access Journals (Sweden)

    Jonathan eFreeman

    2011-04-01

    Full Text Available Recently, researchers have measured hand movements en route to choices on a screen to understand the dynamics of a broad range of psychological processes. We review this growing body of research and explain how manual action exposes the real-time unfolding of underlying cognitive processing. We describe how simple hand motions may be used to continuously index participants’ tentative commitments to different choice alternatives during the evolution of a behavioral response. As such, hand-tracking can provide unusually high-fidelity, real-time motor traces of the mind. These motor traces cast novel theoretical and empirical light onto a wide range of phenomena and serve as a potential bridge between far-reaching areas of psychological science—from language, to high-level cognition and learning, to social cognitive processes.

  16. Repetitive behaviour in autism: Imaging pathways and trajectories

    NARCIS (Netherlands)

    Langen, M.J.G.

    2009-01-01

    Repetitive behaviour in autism: Imaging pathways and trajectories Repetitive and rigid behaviour is one of the core symptoms of autism, a severe and lifelong child psychiatric disorder. Although repetitive behaviour symptoms often form a significant impairment for affected individuals, systematic st

  17. Neural Correlates of Restricted, Repetitive Behaviors in Autism Spectrum Disorders

    Science.gov (United States)

    2014-12-01

    Restrictive Repetitive Behaviors in Autism Spectrum Disorder . Authors: T.Q.Nguyen, B...Manoach. Functional Connectivity of the Dorsal Anterior Cingulate Cortex Predicts Restrictive Repetitive Behaviors in Autism Spectrum Disorder We...Introduction: Although restricted , repetitive behaviors (RRBs) are a highly disabling core feature of Autism Spectrum Disorders (ASDs), they

  18. Lingual Kinematics during Rapid Syllable Repetition in Parkinson's Disease

    Science.gov (United States)

    Wong, Min Ney; Murdoch, Bruce E.; Whelan, Brooke-Mai

    2012-01-01

    Background: Rapid syllable repetition tasks are commonly used in the assessment of motor speech disorders. However, little is known about the articulatory kinematics during rapid syllable repetition in individuals with Parkinson's disease (PD). Aims: To investigate and compare lingual kinematics during rapid syllable repetition in dysarthric…

  19. Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation

    Science.gov (United States)

    Cattani, Amanda Malvessi; Siqueira, Franciele Maboni; Guedes, Rafael Lucas Muniz; Schrank, Irene Silveira

    2016-01-01

    Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5’ upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile. PMID:28005945

  20. Modeling repetitive motions using structured light.

    Science.gov (United States)

    Xu, Yi; Aliaga, Daniel G

    2010-01-01

    Obtaining models of dynamic 3D objects is an important part of content generation for computer graphics. Numerous methods have been extended from static scenarios to model dynamic scenes. If the states or poses of the dynamic object repeat often during a sequence (but not necessarily periodically), we call such a repetitive motion. There are many objects, such as toys, machines, and humans, undergoing repetitive motions. Our key observation is that when a motion-state repeats, we can sample the scene under the same motion state again but using a different set of parameters; thus, providing more information of each motion state. This enables robustly acquiring dense 3D information difficult for objects with repetitive motions using only simple hardware. After the motion sequence, we group temporally disjoint observations of the same motion state together and produce a smooth space-time reconstruction of the scene. Effectively, the dynamic scene modeling problem is converted to a series of static scene reconstructions, which are easier to tackle. The varying sampling parameters can be, for example, structured-light patterns, illumination directions, and viewpoints resulting in different modeling techniques. Based on this observation, we present an image-based motion-state framework and demonstrate our paradigm using either a synchronized or an unsynchronized structured-light acquisition method.