Ang, Kai Keng; Guan, Cuntai; Wang, Chuanchu; Phua, Kok Soon; Tan, Adrian Hock Guan; Chin, Zheng Yang
EEG data from performing motor imagery are usually collected to calibrate a subject-specific model for classifying the EEG data during the evaluation phase of motor imagery Brain-Computer Interface (BCI). However, there is no direct objective measure to determine if a subject is performing motor imagery correctly for proper calibration. Studies have shown that passive movement, which is directly observable, induces Event-Related Synchronization patterns that are similar to those induced from motor imagery. Hence, this paper investigates the feasibility of calibrating EEG-based motor imagery BCI from passive movement. EEG data of 12 healthy subjects were collected during motor imagery and passive movement of the hand by a haptic knob robot. The calibration models using the Filter Bank Common Spatial Pattern algorithm on the EEG data from motor imagery were compared against using the EEG data from passive movement. The performances were compared based on the 10×10-fold cross-validation accuracies of the calibration data, and off-line session-to-session transfer kappa values to other sessions of motor imagery performed on another day. The results showed that the calibration performed using passive movement yielded higher model accuracy and off-line session-to-session transfer (73.6% and 0.354) than the calibration performed using motor imagery (71.3% and 0.311), and no significant differences were observed between the two groups (p=0.20, 0.23). Hence, this study shows that it is feasible to calibrate EEG-based motor imagery BCI from passive movement.
Paleari, Marco; Luciani, Riccardo; Ariano, Paolo
This work reports on preliminary results about on hand movement recognition with Near InfraRed Spectroscopy (NIRS) and surface ElectroMyoGraphy (sEMG). Either basing on physical contact (touchscreens, data-gloves, etc.), vision techniques (Microsoft Kinect, Sony PlayStation Move, etc.), or other modalities, hand movement recognition is a pervasive function in today environment and it is at the base of many gaming, social, and medical applications. Albeit, in recent years, the use of muscle information extracted by sEMG has spread out from the medical applications to contaminate the consumer world, this technique still falls short when dealing with movements of the hand. We tested NIRS as a technique to get another point of view on the muscle phenomena and proved that, within a specific movements selection, NIRS can be used to recognize movements and return information regarding muscles at different depths. Furthermore, we propose here three different multimodal movement recognition approaches and compare their performances.
Roosink, Meyke; Zijdewind, Inge
Movement observation and imagery are increasingly propagandized for motor rehabilitation. Both observation and imagery are thought to improve motor function through repeated activation of mental motor representations. However, it is unknown what stimulation parameters or imagery conditions are
Minsu Song; Jonghyun Kim
Motor imagery (MI) has been widely used in neurorehabilitation and brain computer interface. The size of event-related desynchronization (ERD) is a key parameter for successful motor imaginary rehabilitation and BCI adaptation. Many studies have used visual guidance for enhancement/ amplification of motor imagery ERD amplitude, but their enhancements were not significant. We propose a novel ERD enhancing paradigm using body-ownership illusion, or also known as rubber hand illusion (RHI). The system was made by motorized, moving rubber hand which can simulate wrist extension. The amplifying effects of the proposed RHI paradigm were evaluated by comparing ERD sizes of the proposed paradigm with motor imagery and actual motor execution paradigms. The comparison result shows that the improvement of ERD size due to the proposed paradigm was statistically significant (pparadigms.
Ionta, Silvio; Perruchoud, David; Draganski, Bogdan; Blanke, Olaf
Different visual stimuli have been shown to recruit different mental imagery strategies. However the role of specific visual stimuli properties related to body context and posture in mental imagery is still under debate. Aiming to dissociate the behavioural correlates of mental processing of visual stimuli characterized by different body context, in the present study we investigated whether the mental rotation of stimuli showing either hands as attached to a body (hands-on-body) or not (hands-only), would be based on different mechanisms. We further examined the effects of postural changes on the mental rotation of both stimuli. Thirty healthy volunteers verbally judged the laterality of rotated hands-only and hands-on-body stimuli presented from the dorsum- or the palm-view, while positioning their hands on their knees (front postural condition) or behind their back (back postural condition). Mental rotation of hands-only, but not of hands-on-body, was modulated by the stimulus view and orientation. Additionally, only the hands-only stimuli were mentally rotated at different speeds according to the postural conditions. This indicates that different stimulus-related mechanisms are recruited in mental rotation by changing the bodily context in which a particular body part is presented. The present data suggest that, with respect to hands-only, mental rotation of hands-on-body is less dependent on biomechanical constraints and proprioceptive input. We interpret our results as evidence for preferential processing of visual- rather than kinesthetic-based mechanisms during mental transformation of hands-on-body and hands-only, respectively. PMID:22479618
Jongsma, Marijtje L A; Meulenbroek, Ruud G J; Okely, Judith; Baas, C Marjolein; van der Lubbe, Rob H J; Steenbergen, Bert
Motor imagery (MI) refers to the process of imagining the execution of a specific motor action without actually producing an overt movement. Two forms of MI have been distinguished: visual MI and kinesthetic MI. To distinguish between these forms of MI we employed an event related potential (ERP) study to measure interference effects induced by hand orientation manipulations in a hand laterality judgement task. We hypothesized that this manipulation should only affect kinesthetic MI but not visual MI. The ERPs elicited by rotated hand stimuli contained the classic rotation related negativity (RRN) with respect to palm view stimuli. We observed that laterally rotated stimuli led to a more marked RRN than medially rotated stimuli. This RRN effect was observed when participants had their hands positioned in either a straight (control) or an inward rotated posture, but not when their hands were positioned in an outward rotated posture. Posture effects on the ERP-RRN have not previously been studied. Apparently, a congruent hand posture (hands positioned in an outward rotated fashion) facilitates the judgement of the otherwise more demanding laterally rotated hand stimuli. These ERP findings support a kinesthetic interpretation of MI involved in solving the hand laterality judgement task. The RRN may be used as a non-invasive marker for kinesthetic MI and seems useful in revealing the covert behavior of MI in e.g. rehabilitation programs.
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.
Imbo, Ineke; Vandierendonck, André; Fias, Wim
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 four-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.
Full Text Available Asperger syndrome (AS is a neurodevelopmental condition within the Autism Spectrum Disorders (ASD characterized by specific difficulties in social interaction, communication and behavioural control. In recent years, it has been suggested that ASD is related to a dysfunction of action simulation processes, but studies employing imitation or action observation tasks provided mixed results. Here, we addressed action simulation processes in adolescents with AS by means of a motor imagery task, the classical hand laterality task (to decide whether a rotated hand image is left or right; mental rotation of letters was also evaluated. As a specific marker of action simulation in hand rotation, we assessed the so-called biomechanical effect, that is the advantage for judging hand pictures showing physically comfortable versus physically awkward positions. We found the biomechanical effect in typically-developing participants but not in participants with AS. Overall performance on both hand laterality and letter rotation tasks, instead, did not differ in the two groups. These findings demonstrated a specific alteration of motor imagery skills in AS. We suggest that impaired mental simulation and imitation of goal-less movements in ASD could be related to shared cognitive mechanisms.
Qiu, Zhaoyang; Allison, Brendan Z; Jin, Jing; Zhang, Yu; Wang, Xingyu; Li, Wei; Cichocki, Andrzej
motor imagery (MI) is a mental representation of motor behavior. The MI-based brain computer interfaces (BCIs) can provide communication for the physically impaired. The performance of MI-based BCI mainly depends on the subject's ability to self-modulate electroencephalogram signals. Proper training can help naive subjects learn to modulate brain activity proficiently. However, training subjects typically involve abstract motor tasks and are time-consuming. to improve the performance of naive subjects during motor imagery, a novel paradigm was presented that would guide naive subjects to modulate brain activity effectively. In this new paradigm, pictures of the left or right hand were used as cues for subjects to finish the motor imagery task. Fourteen healthy subjects (11 male, aged 22-25 years, and mean 23.6±1.16) participated in this study. The task was to imagine writing a Chinese character. Specifically, subjects could imagine hand movements corresponding to the sequence of writing strokes in the Chinese character. This paradigm was meant to find an effective and familiar action for most Chinese people, to provide them with a specific, extensively practiced task and help them modulate brain activity. results showed that the writing task paradigm yielded significantly better performance than the traditional arrow paradigm (p paradigm was easier. the proposed new motor imagery paradigm could guide subjects to help them modulate brain activity effectively. Results showed that there were significant improvements using new paradigm, both in classification accuracy and usability.
Yuan, Han; Perdoni, Christopher; He, Bin
The relationship between primary motor cortex and movement kinematics has been shown in nonhuman primate studies of hand reaching or drawing tasks. Studies have demonstrated that the neural activities accompanying or immediately preceding the movement encode the direction, speed and other information. Here we investigated the relationship between the kinematics of imagined and actual hand movement, i.e. the clenching speed, and the EEG activity in ten human subjects. Study participants were asked to perform and imagine clenching of the left hand and right hand at various speeds. The EEG activity in the alpha (8-12 Hz) and beta (18-28 Hz) frequency bands were found to be linearly correlated with the speed of imagery clenching. Similar parametric modulation was also found during the execution of hand movements. A single equation relating the EEG activity to the speed and the hand (left versus right) was developed. This equation, which contained a linear independent combination of the two parameters, described the time-varying neural activity during the tasks. Based on the model, a regression approach was developed to decode the two parameters from the multiple-channel EEG signals. We demonstrated the continuous decoding of dynamic hand and speed information of the imagined clenching. In particular, the time-varying clenching speed was reconstructed in a bell-shaped profile. Our findings suggest an application to providing continuous and complex control of noninvasive brain-computer interface for movement-impaired paralytics.
Olivia Morgan Lapenta
Full Text Available Motor system neural networks are activated during movement imagery, observation and execution, with a neural signature characterized by suppression of the Mu rhythm. In order to investigate the origin of this neurophysiological marker, we tested whether transcranial direct current stimulation (tDCS modifies Mu rhythm oscillations during tasks involving observation and imagery of biological and non-biological movements. We applied tDCS (anodal, cathodal and sham in 21 male participants (mean age 23.8+3.06, over the left M1 with a current of 2mA for 20 minutes. Following this, we recorded the EEG at C3, C4 and Cz and surrounding C3 and C4 electrodes. Analyses of C3 and C4 showed significant effects for biological vs. non-biological movement (p=0.005, and differential hemisphere effects according to the type of stimulation (p=0.04 and type of movement (p=0.02. Analyses of surrounding electrodes revealed significant interaction effects considering type of stimulation and imagery or observation of biological or non-biological movement (p=0.03. The main findings of this study were (i Mu desynchronization during biological movement of the hand region in the contralateral hemisphere after sham tDCS; (ii polarity-dependent modulation effects of tDCS on the Mu rhythm, i.e. anodal tDCS led to Mu synchronization while cathodal tDCS led to Mu desynchronization during movement observation and imagery (iii specific focal and opposite inter-hemispheric effects, i.e. contrary effects for the surrounding electrodes during imagery condition and also for inter-hemispheric electrodes (C3 vs. C4. These findings provide insights into the cortical oscillations during movement observation and imagery. Furthermore it shows that tDCS can be highly focal when guided by a behavioral task.
Lapenta, Olivia M; Minati, Ludovico; Fregni, Felipe; Boggio, Paulo S
Motor system neural networks are activated during movement imagery, observation and execution, with a neural signature characterized by suppression of the Mu rhythm. In order to investigate the origin of this neurophysiological marker, we tested whether transcranial direct current stimulation (tDCS) modifies Mu rhythm oscillations during tasks involving observation and imagery of biological and non-biological movements. We applied tDCS (anodal, cathodal, and sham) in 21 male participants (mean age 23.8 ± 3.06), over the left M1 with a current of 2 mA for 20 min. Following this, we recorded the EEG at C3, C4, and Cz and surrounding C3 and C4 electrodes. Analyses of C3 and C4 showed significant effects for biological vs. non-biological movement (p = 0.005), and differential hemisphere effects according to the type of stimulation (p = 0.04) and type of movement (p = 0.02). Analyses of surrounding electrodes revealed significant interaction effects considering type of stimulation and imagery or observation of biological or non-biological movement (p = 0.03). The main findings of this study were (1) Mu desynchronization during biological movement of the hand region in the contralateral hemisphere after sham tDCS; (2) polarity-dependent modulation effects of tDCS on the Mu rhythm, i.e., anodal tDCS led to Mu synchronization while cathodal tDCS led to Mu desynchronization during movement observation and imagery (3) specific focal and opposite inter-hemispheric effects, i.e., contrary effects for the surrounding electrodes during imagery condition and also for inter-hemispheric electrodes (C3 vs. C4). These findings provide insights into the cortical oscillations during movement observation and imagery. Furthermore, it shows that tDCS can be highly focal when guided by a behavioral task.
Hyde, Christian; Fuelscher, Ian; Lum, Jarrad A G; Williams, Jacqueline; He, Jason; Enticott, Peter G
It is unclear whether the primary motor cortex (PMC) is involved in the mental simulation of movement [i.e., motor imagery (MI)]. The present study aimed to clarify PMC involvement using a highly novel adaptation of the hand laterality task (HLT). Participants were administered single-pulse transcranial magnetic stimulation (TMS) to the hand area of the left PMC (hPMC) at either 50 ms, 400 ms, or 650 ms post stimulus presentation. Motor-evoked potentials (MEPs) were recorded from the right first dorsal interosseous via electromyography. To avoid the confound of gross motor response, participant response (indicating left or right hand) was recorded via eye tracking. Participants were 22 healthy adults (18 to 36 years), 16 whose behavioral profile on the HLT was consistent with the use of a MI strategy (MI users). hPMC excitability increased significantly during HLT performance for MI users, evidenced by significantly larger right hand MEPs following single-pulse TMS 50 ms, 400 ms, and 650 ms post stimulus presentation relative to baseline. Subsequent analysis showed that hPMC excitability was greater for more complex simulated hand movements, where hand MEPs at 50 ms were larger for biomechanically awkward movements (i.e., hands requiring lateral rotation) compared to simpler movements (i.e., hands requiring medial rotation). These findings provide support for the modulation of PMC excitability during the HLT attributable to MI, and may indicate a role for the PMC during MI. (JINS, 2017, 23, 185-193).
Thomas, F A; Dietz, V; Schrafl-Altermatt, M
Cooperative hand movements (e.g. opening a bottle) are controlled by a task-specific neural coupling, reflected in EMG reflex responses contralateral to the stimulation site. In this study the contralateral reflex responses in forearm extensor muscles to ipsilateral ulnar nerve stimulation was analyzed at various resistance and velocities of cooperative hand movements. The size of contralateral reflex responses was closely related to the level of forearm muscle activation required to accomplish the various cooperative hand movement tasks. This indicates an automatic gain control of neural coupling that allows a rapid matching of corrective forces exerted at both sides of an object with the goal 'two hands one action'.
Girón, Elizabeth Coker; McIsaac, Tara; Nilsen, Dawn
Motor imagery is a type of mental practice that involves imagining the body performing a movement in the absence of motor output. Dance training traditionally incorporates mental practice techniques, but quantitative effects of motor imagery on the performance of dance movements are largely unknown. This pilot study compared the effects of two different imagery modalities, external visual imagery and kinesthetic imagery, on pelvis and hip kinematics during two technical dance movements, plié and sauté. Each of three female dance students (mean age = 19.7 years, mean years of training = 10.7) was assigned to use a type of imagery practice: visual imagery, kinesthetic imagery, or no imagery. Effects of motor imagery on peak external hip rotation varied by both modality and task. Kinesthetic imagery increased peak external hip rotation for pliés, while visual imagery increased peak external hip rotation for sautés. Findings suggest that the success of motor imagery in improving performance may be task-specific. Dancers may benefit from matching imagery modality to technical tasks in order to improve alignment and thereby avoid chronic injury.
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.
Tobing, T. A. M. L.; Prawito, Wijaya, S. K.
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.
Ay, Khitam Mousa; Halaweh, Rami Saleh; Al-Taieb, Mohammad Abu
This study investigates the effect of movement imagery on learning the forearm pass in volleyball. Twenty four mail students from Physical Education Factuly at Jordan University (19 ± 0.5) years of age. After Completed the Movement Imagery Questionnaire-Revised (MIQ-R; Hall & Martin, 1997) the subjects randomly divided into two groups,…
Braun, Susy M.; Wade, Derick T.; Beurskens, Anna J. H. M.
Since the beginning of the new millennium, the use of mental practice and movement imagery within several medical professions in rehabilitation and therapy has received an increased attention. Before this introduction in healthcare, the use of movement imagery was mainly researched in sports science. Mental practice is a complex intervention. When…
Elich, Matthew; And Others
Tested Bandler and Grinder's proposal that eye movement direction and spoken predicates are indicative of sensory modality of imagery. Subjects reported images in the three modes, but no relation between imagery and eye movements or predicates was found. Visual images were most vivid and often reported. Most subjects rated themselves as visual,…
Conson, Massimiliano; Volpicella, Francesco; De Bellis, Francesco; Orefice, Agnese; Trojano, Luigi
A key point in motor imagery literature is that judging hands in palm view recruits sensory-motor information to a higher extent than judging hands in back view, due to the greater biomechanical complexity implied in rotating hands depicted from palm than from back. We took advantage from this solid evidence to test the nature of a phenomenon known as self-advantage, i.e. the advantage in implicitly recognizing self vs. others' hand images. The self-advantage has been actually found when implicitly but not explicitly judging self-hands, likely due to dissociation between implicit and explicit body representations. However, such a finding might be related to the extent to which motor imagery is recruited during implicit and explicit processing of hand images. We tested this hypothesis in two behavioural experiments. In Experiment 1, right-handed participants judged laterality of either self or others' hands, whereas in Experiment 2, an explicit recognition of one's own hands was required. Crucially, in both experiments participants were randomly presented with hand images viewed from back or from palm. The main result of both experiments was the self-advantage when participants judged hands from palm view. This novel finding demonstrate that increasing the "motor imagery load" during processing of self vs. others' hands can elicit a self-advantage in explicit recognition tasks as well. Future studies testing the possible dissociation between implicit and explicit visual body representations should take into account the modulatory effect of motor imagery load on self-hand processing. Copyright © 2017. Published by Elsevier B.V.
Sobierajewicz, Jagna; Przekoracka-Krawczyk, Anna; Jaśkowski, Wojciech; Verwey, Willem B.; van der Lubbe, Rob
Motor imagery has been argued to affect the acquisition of motor skills. The present study examined the specificity of motor imagery on the learning of a fine hand motor skill by employing a modified discrete sequence production task: the Go/NoGo DSP task. After an informative cue, a response
Jongsma, M.A.; Meulenbroek, R.G.J.; Okely, J.; Baas, M.; Baas, M.; van der Lubbe, Robert Henricus Johannes; Steenbergen, B.
Motor imagery (MI) refers to the process of imagining the execution of a specific motor action without actually producing an overt movement. Two forms of MI have been distinguished: visual MI and kinesthetic MI. To distinguish between these forms of MI we employed an event related potential (ERP)
Jongsma, M.L.A.; Meulenbroek, R.G.J.; Okely, J.; Baas, C.M.; Lubbe, R.H.J. van der; Steenbergen, B.
Motor imagery (MI) refers to the process of imagining the execution of a specific motor action without actually producing an overt movement. Two forms of MI have been distinguished: visual MI and kinesthetic MI. To distinguish between these forms of MI we employed an event related potential (ERP)
Jongsma, M.L.A.; Meulenbroek, R.G.; Okely, J.; Baas, C.M.; Lubbe, R.H. van der; Steenbergen, B.
Motor imagery (MI) refers to the process of imagining the execution of a specific motor action without actually producing an overt movement. Two forms of MI have been distinguished: visual MI and kinesthetic MI. To distinguish between these forms of MI we employed an event related potential (ERP)
Marasco, Paul D.; Hebert, Jacqueline S.; Sensinger, Jon W.; Shell, Courtney E.; Schofield, Jonathon S.; Thumser, Zachary C.; Nataraj, Raviraj; Beckler, Dylan T.; Dawson, Michael R.; Blustein, Dan H.; Gill, Satinder; Mensh, Brett D.; Granja-Vazquez, Rafael; Newcomb, Madeline D.; Carey, Jason P.; Orzell, Beth M.
To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement’s progress. This largely non-conscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. Here we report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. PMID:29540617
Jaël S. van Bentum
Full Text Available Suicide and suicidal behavior are major public health concerns, and affect 3–9% of the population worldwide. Despite increased efforts for national suicide prevention strategies, there are still few effective interventions available for reducing suicide risk. In this article, we describe various theoretical approaches for suicide ideation and behavior, and propose to examine the possible effectiveness of a new and innovative preventive strategy. A model of suicidal intrusion (mental imagery related to suicide, also referred to as suicidal flash-forwards is presented describing one of the assumed mechanisms in the etiology of suicide and the mechanism of therapeutic change. We provide a brief rationale for an Eye Movement Dual Task (EMDT treatment for suicidal intrusions, describing techniques that can be used to target these suicidal mental images and thoughts to reduce overall behavior. Based on the available empirical evidence for the mechanisms of suicidal intrusions, this approach appears to be a promising new treatment to prevent suicidal behavior as it potentially targets one of the linking pins between suicidal ideation and suicidal actions.
Full Text Available Improving the sense of immersion is one of the core issues in virtual reality. Perceptual illusions of ownership can be perceived over a virtual body in a multisensory virtual reality environment. Rubber Hand and Virtual Hand Illusions showed that body ownership can be manipulated by applying suitable visual and tactile stimulation. In this study, we investigate the effects of multisensory integration in the Virtual Hand Illusion with active movement. A virtual xylophone playing system which can interactively provide synchronous visual, tactile, and auditory stimulation was constructed. We conducted two experiments regarding different movement conditions and different sensory stimulations. Our results demonstrate that multisensory integration with free active movement can improve the sense of immersion in virtual reality.
Choi, Woong; Li, Liang; Satoh, Satoru; Hachimura, Kozaburo
Improving the sense of immersion is one of the core issues in virtual reality. Perceptual illusions of ownership can be perceived over a virtual body in a multisensory virtual reality environment. Rubber Hand and Virtual Hand Illusions showed that body ownership can be manipulated by applying suitable visual and tactile stimulation. In this study, we investigate the effects of multisensory integration in the Virtual Hand Illusion with active movement. A virtual xylophone playing system which can interactively provide synchronous visual, tactile, and auditory stimulation was constructed. We conducted two experiments regarding different movement conditions and different sensory stimulations. Our results demonstrate that multisensory integration with free active movement can improve the sense of immersion in virtual reality.
Duann, Jeng-Ren; Chiou, Jin-Chern
Electroencephalographic (EEG) event-related desynchronization (ERD) induced by movement imagery or by observing biological movements performed by someone else has recently been used extensively for brain-computer interface-based applications, such as applications used in stroke rehabilitation training and motor skill learning. However, the ERD responses induced by the movement imagery and observation might not be as reliable as the ERD responses induced by movement execution. Given that studies on the reliability of the EEG ERD responses induced by these activities are still lacking, here we conducted an EEG experiment with movement imagery, movement observation, and movement execution, performed multiple times each in a pseudorandomized order in the same experimental runs. Then, independent component analysis (ICA) was applied to the EEG data to find the common motor-related EEG source activity shared by the three motor tasks. Finally, conditional EEG ERD responses associated with the three movement conditions were computed and compared. Among the three motor conditions, the EEG ERD responses induced by motor execution revealed the alpha power suppression with highest strengths and longest durations. The ERD responses of the movement imagery and movement observation only partially resembled the ERD pattern of the movement execution condition, with slightly better detectability for the ERD responses associated with the movement imagery and faster ERD responses for movement observation. This may indicate different levels of involvement in the same motor-related brain circuits during different movement conditions. In addition, because the resulting conditional EEG ERD responses from the ICA preprocessing came with minimal contamination from the non-related and/or artifactual noisy components, this result can play a role of the reference for devising a brain-computer interface using the EEG ERD features of movement imagery or observation.
Spruijt, S.; Jongsma, M.L.; Kamp, J. van der; Steenbergen, B.
A commonly used paradigm to study motor imagery is the hand laterality judgment task. The present study aimed to determine which strategies young children employ to successfully perform this task. Children of 5 to 8 years old (N = 92) judged laterality of back and palm view hand pictures in
Spruijt, S; Jongsma, M.L.A.; van der Kamp, J.; Steenbergen, B.
A commonly used paradigm to study motor imagery is the hand laterality judgment task. The present study aimed to determine which strategies young children employ to successfully perform this task. Children of 5 to 8 years old (N = 92) judged laterality of back and palm view hand pictures in
Roel M Willems
Full Text Available If motor imagery uses neural structures involved in action execution, then the neural correlates of imagining an action should differ between individuals who tend to execute the action differently. Here we report fMRI data showing that motor imagery is influenced by the way people habitually perform motor actions with their particular bodies; that is, motor imagery is ‘body-specific’ (Casasanto, 2009. During mental imagery for complex hand actions, activation of cortical areas involved in motor planning and execution was left-lateralized in right-handers but right-lateralized in left-handers. We conclude that motor imagery involves the generation of an action plan that is grounded in the participant’s motor habits, not just an abstract representation at the level of the action’s goal. People with different patterns of motor experience form correspondingly different neurocognitive representations of imagined actions.
Grabherr, Luzia; Jola, Corinne; Berra, Gilberto; Theiler, Robert; Mast, Fred W
In healthy participants, beneficial effects of motor imagery training on movement execution have been shown for precision, strength, and speed. In the clinical context, it is still debated whether motor imagery provides an effective rehabilitation technique in patients with motor deficits. To compare the effectiveness of two different types of movement training: motor imagery vs. motor execution. Twenty-five patients with hemiparesis were assigned to one of two training groups: the imagery or the execution-training group. Both groups completed a baseline test before they received six training sessions, each of which was followed by a test session. Using a novel and precisely quantifiable test, we assessed how accurately patients performed an upper limb movement. Both training groups improved performance over the six test sessions but the improvement was significantly larger in the imagery group. That is, the imagery group was able to perform more precise movements than the execution group after the sixth training session while there was no difference at the beginning of the training. The results provide evidence for the benefit of motor imagery training in patients with hemiparesis and thus suggest the integration of cognitive training in conventional physiotherapy practice.
Marasco, Paul D; Hebert, Jacqueline S; Sensinger, Jon W; Shell, Courtney E; Schofield, Jonathon S; Thumser, Zachary C; Nataraj, Raviraj; Beckler, Dylan T; Dawson, Michael R; Blustein, Dan H; Gill, Satinder; Mensh, Brett D; Granja-Vazquez, Rafael; Newcomb, Madeline D; Carey, Jason P; Orzell, Beth M
To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement's progress. This largely nonconscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. We report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
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.
Spruijt, Steffie; Jongsma, Marijtje L A; van der Kamp, John; Steenbergen, Bert
A commonly used paradigm to study motor imagery is the hand laterality judgment task. The present study aimed to determine which strategies young children employ to successfully perform this task. Children of 5 to 8 years old (N = 92) judged laterality of back and palm view hand pictures in different rotation angles. Response accuracy and response duration were registered. Response durations of the trials with a correct judgment were fitted to a-priori defined predictive sinusoid models, representing different strategies to successfully perform the hand laterality judgment task. The first model predicted systematic changes in response duration as a function of rotation angle of the displayed hand. The second model predicted that response durations are affected by biomechanical constraints of hand rotation. If observed data could be best described by the first model, this would argue for a mental imagery strategy that does not involve motor processes to solve the task. The second model reflects a motor imagery strategy to solve the task. In line with previous research, we showed an age-related increase in response accuracy and decrease in response duration in children. Observed data for both back and palm view showed that motor imagery strategies were used to perform hand laterality judgments, but that not all the children use these strategies (appropriately) at all times. A direct comparison of response duration patterns across age sheds new light on age-related differences in the strategies employed to solve the task. Importantly, the employment of the motor imagery strategy for successful task performance did not change with age.
Bartoli, Eleonora; Maffongelli, Laura; Jacono, Marco; D'Ausilio, Alessandro
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. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Robinson, Sally; Woods, Martin; Cardona, Francesco; Baglioni, Valentina; Hedderly, Tammy
The aim of this article is to describe a subgroup of children who presented with stereotyped movements in the context of episodes of intense imagery. This is of relevance to current discussions regarding the clinical usefulness of diagnosing motor stereotypies during development. The sample consisted of 10 children (nine males, one female; mean age 8y 6mo [SD 2y 5mo], range 6-15y). Referrals were from acute paediatricians, neurologists, and tertiary epilepsy services. Children were assessed by multidisciplinary teams with expertise in paediatric movement disorders. Stereotypies presented as paroxysmal complex movements involving upper and lower limbs. Imagery themes typically included computer games (60%), cartoons/films (40%), and fantasy scenes (30%). Comorbid developmental difficulties were reported for 80% of children. Brain imaging and electrophysiological investigations had been conducted for 50% of the children before referral to the clinic. The descriptive term 'intense imagery movements' (IIM) was applied if (after interview) the children reported engaging in acts of imagery while performing stereotyped movements. We believe these children may form a common and discrete stereotypy subgroup, with the concept of IIM being clinically useful to ensure the accurate diagnosis and clinical management of this paediatric movement disorder. © 2014 Mac Keith Press.
Mizuguchi, N; Nakata, H; Kanosue, K
To elucidate the neural substrate associated with capabilities for kinesthetic motor imagery of difficult whole-body movements, we measured brain activity during a trial involving both kinesthetic motor imagery and action observation as well as during a trial with action observation alone. Brain activity was assessed with functional magnetic resonance imaging (fMRI). Nineteen participants imagined three types of whole-body movements with the horizontal bar: the giant swing, kip, and chin-up during action observation. No participant had previously tried to perform the giant swing. The vividness of kinesthetic motor imagery as assessed by questionnaire was highest for the chin-up, less for the kip and lowest for the giant swing. Activity in the primary visual cortex (V1) during kinesthetic motor imagery with action observation minus that during action observation alone was significantly greater in the giant swing condition than in the chin-up condition within participants. Across participants, V1 activity of kinesthetic motor imagery of the kip during action observation minus that during action observation alone was negatively correlated with vividness of the kip imagery. These results suggest that activity in V1 is dependent upon the capability of kinesthetic motor imagery for difficult whole-body movements. Since V1 activity is likely related to the creation of a visual image, we speculate that visual motor imagery is recruited unintentionally for the less vivid kinesthetic motor imagery of difficult whole-body movements. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Full Text Available Background Imagery is often beneficial not only in gaining a psychological advantage when competing but also in building self-esteem and self-confidence. The aim of this study was to examine the reliability and validity of the Polish adaptation of the Movement Imagery Questionnaire-3 (MIQ-3, consisting of 12 questions measuring 3 dimensions: visual internal imagery, visual external imagery and kinesthetic imagery. Participants and procedure A sample of athletes (N = 276 – 102 women, 174 men (M = 21.25, SD = 6.35 of various disciplines (football, volleyball, karate, swimming, etc. with different sport experience (from recreation to the national team filled in the MIQ-3 questionnaire in the Polish language. Results The results of the confirmatory factor analysis (CFA with maximum likelihood confirmed that the established three-factor model reflects well the relationships observed in the respondents’ answers (satisfactory value of RMSEA below the recommended value of .05 (RMSEA = .04 and a high value of the index above .90 CFI (CFI = .93. Reliability indicators (composite reliability – CR observed for individual factors indicated a very high internal consistency (external visual imagery = .75, internal visual imagery = .79 and kinesthetic imagery = .82. The results indicated that good stability and internal consistency were maintained over a 3-week period. In addition, analyses were examined across age, level of experience and gender. Conclusions The results of the present study support the psychometric properties of the Polish adaptation of the MIQ-3.
Full Text Available A repetitive movement practice by motor imagery (MI can inﬂuence motor cortical excitability in the electroencephalogram (EEG. The feedback and the feedback environment should be inherently motivating and relevant for the learner and should have an appeal of novelty, real-world relevance or aesthetic value (Ryan and Deci, 2000; Merrill, 2007. This study investigated if a realistic visualization in 3D of upper and lower limb movements can amplify motor related potentials during motor imagery. We hypothesized that a richer sensory visualization might be more effective during instrumental conditioning, resulting in a more pronounced event related desynchronisation (ERD of the upper alpha band (10-12 Hz over the sensorimotor cortices thereby potentially improving MI based BCI protocols for motor rehabilitation. The results show a strong increase of the characteristic patterns of ERD of the upper alpha band components for left and right limb motor imagery present over the sensorimotor areas in both visualization conditions. Overall, significant differences were observed as a function of visualization modality (2D vs. 3D. The largest upper alpha band power decrease was obtained during motor imagery after a 3-dimensional visualization. In total in 12 out of 20 tasks the end-user of the 3D visualization group showed an enhanced upper alpha ERD relative to 2D visualization modality group, with statistical significance in nine tasks.With a realistic visualization of the limb movements, we tried to increase motor cortex activation during MI. Realistic visual feedback, consistent with the participant’s motor imagery, might be helpful for accomplishing successful motor imagery and the use of such feedback may assist in making BCI a more natural interface for motor imagery based BCI rehabilitation.
Full Text Available Further development of an EEG based communication device for patients with disorders of consciousness (DoC could benefit from addressing the following gaps in knowledge – first, an evaluation of different types of motor imagery; second, an evaluation of passive feet movement as a mean of an initial classifier setup; and third, rapid delivery of biased feedback. To that end we investigated whether complex and / or familiar mental imagery, passive, and attempted feet movement can be reliably detected in patients with DoC using EEG recordings, aiming to provide them with a means of communication. Six patients in a minimally conscious state (MCS took part in this study. The patients were verbally instructed to perform different mental imagery tasks (sport, navigation, as well as attempted feet movements, to induce distinctive event-related (desynchronization (ERD/S patterns in the EEG. Offline classification accuracies above chance level were reached in all three tasks (i.e. attempted feet, sport, and navigation, with motor tasks yielding significant (p<0.05 results more often than navigation (sport: 10 out of 18 sessions; attempted feet: 7 out of 14 sessions; navigation: 4 out of 12 sessions. The passive feet movements, evaluated in one patient, yielded mixed results: whereas time-frequency analysis revealed task-related EEG changes over neurophysiological plausible cortical areas, the classification results were not significant enough (p<0.05 to setup an initial classifier for the detection of attempted movements. Concluding, the results presented in this study are consistent with the current state of the art in similar studies, to which we contributed by comparing different types of mental tasks, notably complex motor imagery and attempted feet movements, within patients. Furthermore, we explored new venues, such as an evaluation of passive feet movement as a mean of an initial classifier setup, and rapid delivery of biased feedback.
Sobierajewicz, Jagna; Jaskowski, Wojciech; van der Lubbe, Robert Henricus Johannes
Learning a fine sequential hand motor skill, comparable to playing the piano or learning to type, improves not only due to physical practice, but also due to motor imagery. Previous studies revealed that transcranial direct current stimulation (tDCS) and motor imagery independently affect motor
Burke, Melanie R; Allen, Richard J; Gonzalez, Claudia
Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (e.g., Awh et al, 2006 Neuroscience 139 201-208). 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 10 s) 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 suggesting higher cognitive effort. Fixation duration on target at recall was also influenced by whether spatial location was initially signalled by colour or shape change. Finally, we found that the sequence tasks encouraged longer fixations on the signalled targets than simultaneous viewing during encoding, but no difference was observed during recall. We conclude that the attentional manipulations (colour/shape) mainly affected the eye movement parameters, whereas the memory manipulation (sequential versus simultaneous, number of items) mainly affected the performance of the hand during recall, and thus the latter is more important for ascertaining if an item is remembered or forgotten. In summary, the nature of the stimuli that is used and how it is presented play key roles in determining subject performance and behaviour during spatial memory tasks.
Wright, Tessa; Wormsley, Diane P.; Kamei-Hannan, Cheryl
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…
Frolov, Alexander A; Mokienko, Olesya; Lyukmanov, Roman; Biryukova, Elena; Kotov, Sergey; Turbina, Lydia; Nadareyshvily, Georgy; Bushkova, Yulia
Repeated use of brain-computer interfaces (BCIs) providing contingent sensory feedback of brain activity was recently proposed as a rehabilitation approach to restore motor function after stroke or spinal cord lesions. However, there are only a few clinical studies that investigate feasibility and effectiveness of such an approach. Here we report on a placebo-controlled, multicenter clinical trial that investigated whether stroke survivors with severe upper limb (UL) paralysis benefit from 10 BCI training sessions each lasting up to 40 min. A total of 74 patients participated: median time since stroke is 8 months, 25 and 75% quartiles [3.0; 13.0]; median severity of UL paralysis is 4.5 points [0.0; 30.0] as measured by the Action Research Arm Test, ARAT, and 19.5 points [11.0; 40.0] as measured by the Fugl-Meyer Motor Assessment, FMMA. Patients in the BCI group ( n = 55) performed motor imagery of opening their affected hand. Motor imagery-related brain electroencephalographic activity was translated into contingent hand exoskeleton-driven opening movements of the affected hand. In a control group ( n = 19), hand exoskeleton-driven opening movements of the affected hand were independent of brain electroencephalographic activity. Evaluation of the UL clinical assessments indicated that both groups improved, but only the BCI group showed an improvement in the ARAT's grasp score from 0 [0.0; 14.0] to 3.0 [0.0; 15.0] points ( p exoskeleton-assisted physical therapy can improve post-stroke rehabilitation outcomes. Both maximum and mean values of the percentage of successfully decoded imagery-related EEG activity, were higher than chance level. A correlation between the classification accuracy and the improvement in the upper extremity function was found. An improvement of motor function was found for patients with different duration, severity and location of the stroke.
Pinto, Serge; Mancini, Laura; Jahanshahi, Marjan; Thornton, John S; Tripoliti, Elina; Yousry, Tarek A; Limousin, Patricia
Among the repertoire of motor functions, although hand movement and speech production tasks have been investigated widely by functional neuroimaging, paradigms combining both movements have been studied less so. Such paradigms are of particular interest in Parkinson's disease, in which patients have specific difficulties performing two movements simultaneously. In 9 unmedicated patients with Parkinson's disease and 15 healthy control subjects, externally cued tasks (i.e., hand movement, speech production, and combined hand movement and speech production) were performed twice in a random order and functional magnetic resonance imaging detected cerebral activations, compared to the rest. F-statistics tested within-group (significant activations at P values 10 voxels). For control subjects, the combined task activations comprised the sum of those obtained during hand movement and speech production performed separately, reflecting the neural correlates of performing movements sharing similar programming modalities. In patients with Parkinson's disease, only activations underlying hand movement were observed during the combined task. We interpreted this phenomenon as patients' potential inability to recruit facilitatory activations while performing two movements simultaneously. This lost capacity could be related to a functional prioritization of one movement (i.e., hand movement), in comparison with the other (i.e., speech production). Our observation could also reflect the inability of patients with Parkinson's disease to intrinsically engage the motor coordination necessary to perform a combined task. Copyright © 2011 Movement Disorder Society.
Flávia Priscila de Paiva Silva
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.
Andrew J. Butler
Full Text Available Mental imagery can improve motor performance in stroke populations when combined with physical therapy. Valid and reliable instruments to evaluate the imagery ability of stroke survivors are needed to maximize the benefits of mental imagery therapy. The purposes of this study were to: examine and compare the test-retest intra-rate reliability of the Movement Imagery Questionnaire-Revised, Second Edition (MIQ-RS in stroke survivors and able-bodied controls, examine internal consistency of the visual and kinesthetic items of the MIQ-RS, determine if the MIQ-RS includes both the visual and kinesthetic dimensions of mental imagery, correlate impairment and motor imagery scores, and investigate the criterion validity of the MIQ-RS in stroke survivors by comparing the results to the KVIQ-10. Test-retest analysis indicated good levels of reliability (ICC range: .83–.99 and internal consistency (Cronbach α: .95–.98 of the visual and kinesthetic subscales in both groups. The two-factor structure of the MIQ-RS was supported by factor analysis, with the visual and kinesthetic components accounting for 88.6% and 83.4% of the total variance in the able-bodied and stroke groups, respectively. The MIQ-RS is a valid and reliable instrument in the stroke population examined and able-bodied populations and therefore useful as an outcome measure for motor imagery ability.
Full Text Available Brain-computer interface (BCI has attracted great interests for its effectiveness in assisting disabled people. However, due to the poor BCI performance, this technique is still far from daily-life applications. One of critical issues confronting BCI research is how to enhance BCI performance. This study aimed at improving the motor imagery (MI based BCI accuracy by integrating MI tasks with unilateral tactile stimulation (Uni-TS. The effects were tested on both healthy subjects and stroke patients in a controlled study. Twenty-two healthy subjects and four stroke patients were recruited and randomly divided into a control-group and an enhanced-group. In the control-group, subjects performed two blocks of conventional MI tasks (left hand vs. right hand, with 80 trials in each block. In the enhanced-group, subjects also performed two blocks of MI tasks, but constant tactile stimulation was applied on the non-dominant/paretic hand during MI tasks in the second block. We found the Uni-TS significantly enhanced the contralateral cortical activations during MI of the stimulated hand, whereas it had no influence on activation patterns during MI of the non-stimulated hand. The two-class BCI decoding accuracy was significantly increased from 72.5% (MI without Uni-TS to 84.7% (MI with Uni-TS in the enhanced-group (p < 0.001, paired t-test. Moreover, stroke patients in the enhanced-group achieved an accuracy >80% during MI with Uni-TS. This novel approach complements the conventional methods for BCI enhancement without increasing source information or complexity of signal processing. This enhancement via Uni-TS may facilitate clinical applications of MI-BCI.
Johari, Karim; Behroozmand, Roozbeh
Skilled movement is mediated by motor commands executed with extremely fine temporal precision. The question of how the brain incorporates temporal information to perform motor actions has remained unanswered. This study investigated the effect of stimulus temporal predictability on response timing of speech and hand movement. Subjects performed a randomized vowel vocalization or button press task in two counterbalanced blocks in response to temporally-predictable and unpredictable visual cues. Results indicated that speech and hand reaction time was decreased for predictable compared with unpredictable stimuli. This finding suggests that a temporal predictive code is established to capture temporal dynamics of sensory cues in order to produce faster movements in responses to predictable stimuli. In addition, results revealed a main effect of modality, indicating faster hand movement compared with speech. We suggest that this effect is accounted for by the inherent complexity of speech production compared with hand movement. Lastly, we found that movement inhibition was faster than initiation for both hand and speech, suggesting that movement initiation requires a longer processing time to coordinate activities across multiple regions in the brain. These findings provide new insights into the mechanisms of temporal information processing during initiation and inhibition of speech and hand movement. Copyright © 2017 Elsevier B.V. All rights reserved.
Boonstra, Anne M.; de Vries, Sjoerd J.; Veenstra, Evelien; Tepper, Marga; Feenstra, Wya; Otten, Egbert
The aim of this study was to determine whether there is a practice effect on the Hand Laterality Judgement Task (HLJT). The HLJT task is a mental rotation task that can be used to assess motor imagery ability in stroke patients. Thirty-three healthy individuals performed the HLJT and two control
Boonstra, Anne M.; de Vries, Sjoerd J.; Veenstra, Evelien; Tepper, Marga; Feenstra, Wya; Otten, Egbert
The aim of this study was to determine whether there is a practice effect on the Hand Laterality Judgement Task (HLJT). The HLJT task is a mental rotation task that can be used to assess motor imagery ability in stroke patients. Thirty-three healthy individuals performed the HLJT and two control tasks twice at a 3-week interval. Differences in the…
Keller, Peter E; Dalla Bella, Simone; Koch, Iring
The role of anticipatory auditory imagery in music-like sequential action was investigated by examining timing accuracy and kinematics using a motion capture system. Musicians responded to metronomic pacing signals by producing three unpaced taps on three vertically aligned keys at the given tempo. Taps triggered tones in two out of three blocked feedback conditions, where key-to-tone mappings were compatible or incompatible in terms of spatial and pitch height. Results indicate that, while timing was most accurate without tones, movements were smaller in amplitude and less forceful (i.e., acceleration prior to impact was lowest) when tones were present. Moreover, timing was more accurate and movements were less forceful with compatible than with incompatible auditory feedback. Observing these effects at the first tap (before tone onset) suggests that anticipatory auditory imagery modulates the temporal kinematics of regularly timed auditory action sequences, like those found in music. Such cross-modal ideomotor processes may function to facilitate planning efficiency and biomechanical economy in voluntary action. Copyright 2010 APA, all rights reserved.
Liakhovetskiĭ, V A; Bobrova, E V; Skopin, G N
Transposition errors during the reproduction of a hand movement sequence make it possible to receive important information on the internal representation of this sequence in the motor working memory. Analysis of such errors showed that learning to reproduce sequences of the left-hand movements improves the system of positional coding (coding ofpositions), while learning of the right-hand movements improves the system of vector coding (coding of movements). Learning of the right-hand movements after the left-hand performance involved the system of positional coding "imposed" by the left hand. Learning of the left-hand movements after the right-hand performance activated the system of vector coding. Transposition errors during learning to reproduce movement sequences can be explained by neural network using either vector coding or both vector and positional coding.
Burke, MR; Allen, RJ; Gonzalez, C
© 2012 a Pion publication Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (e.g., Awh et al, 2006 Neuroscience 139 201-208). 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 de...
Melanie Rose Burke; Richard Allen; Matilda Webster; Claudia Gonzalez
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 tar...
Alexander A. Frolov
Full Text Available Repeated use of brain-computer interfaces (BCIs providing contingent sensory feedback of brain activity was recently proposed as a rehabilitation approach to restore motor function after stroke or spinal cord lesions. However, there are only a few clinical studies that investigate feasibility and effectiveness of such an approach. Here we report on a placebo-controlled, multicenter clinical trial that investigated whether stroke survivors with severe upper limb (UL paralysis benefit from 10 BCI training sessions each lasting up to 40 min. A total of 74 patients participated: median time since stroke is 8 months, 25 and 75% quartiles [3.0; 13.0]; median severity of UL paralysis is 4.5 points [0.0; 30.0] as measured by the Action Research Arm Test, ARAT, and 19.5 points [11.0; 40.0] as measured by the Fugl-Meyer Motor Assessment, FMMA. Patients in the BCI group (n = 55 performed motor imagery of opening their affected hand. Motor imagery-related brain electroencephalographic activity was translated into contingent hand exoskeleton-driven opening movements of the affected hand. In a control group (n = 19, hand exoskeleton-driven opening movements of the affected hand were independent of brain electroencephalographic activity. Evaluation of the UL clinical assessments indicated that both groups improved, but only the BCI group showed an improvement in the ARAT's grasp score from 0 [0.0; 14.0] to 3.0 [0.0; 15.0] points (p < 0.01 and pinch scores from 0.0 [0.0; 7.0] to 1.0 [0.0; 12.0] points (p < 0.01. Upon training completion, 21.8% and 36.4% of the patients in the BCI group improved their ARAT and FMMA scores respectively. The corresponding numbers for the control group were 5.1% (ARAT and 15.8% (FMMA. These results suggests that adding BCI control to exoskeleton-assisted physical therapy can improve post-stroke rehabilitation outcomes. Both maximum and mean values of the percentage of successfully decoded imagery-related EEG activity, were higher
Cui, Phil Hengjun; Visell, Yon
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.
Amesz, Sarah; Tessari, Alessia; Ottoboni, Giovanni; Marsden, Jon
To explore the relationship between laterality recognition after stroke and impairments in attention, 3D object rotation and functional ability. Observational cross-sectional study. Acute care teaching hospital. Thirty-two acute and sub-acute people with stroke and 36 healthy, age-matched controls. Laterality recognition, attention and mental rotation of objects. Within the stroke group, the relationship between laterality recognition and functional ability, neglect, hemianopia and dyspraxia were further explored. People with stroke were significantly less accurate (69% vs 80%) and showed delayed reaction times (3.0 vs 1.9 seconds) when determining the laterality of a pictured hand. Deficits either in accuracy or reaction times were seen in 53% of people with stroke. The accuracy of laterality recognition was associated with reduced functional ability (R(2) = 0.21), less accurate mental rotation of objects (R(2) = 0.20) and dyspraxia (p = 0.03). Implicit motor imagery is affected in a significant number of patients after stroke with these deficits related to lesions to the motor networks as well as other deficits seen after stroke. This research provides new insights into how laterality recognition is related to a number of other deficits after stroke, including the mental rotation of 3D objects, attention and dyspraxia. Further research is required to determine if treatment programmes can improve deficits in laterality recognition and impact functional outcomes after stroke.
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.
Xia, Bin; Cao, Lei; Maysam, Oladazimi; Li, Jie; Xie, Hong; Su, Caixia; Birbaumer, Niels
Objective. Two-dimensional movement control is a popular issue in brain-computer interface (BCI) research and has many applications in the real world. In this paper, we introduce a combined control strategy to a binary class-based BCI system that allows the user to move a cursor in a two-dimensional (2D) plane. Users focus on a single moving vector to control 2D movement instead of controlling vertical and horizontal movement separately. Approach. Five participants took part in a fixed-target experiment and random-target experiment to verify the effectiveness of the combination control strategy under the fixed and random routine conditions. Both experiments were performed in a virtual 2D dimensional environment and visual feedback was provided on the screen. Main results. The five participants achieved an average hit rate of 98.9% and 99.4% for the fixed-target experiment and the random-target experiment, respectively. Significance. The results demonstrate that participants could move the cursor in the 2D plane effectively. The proposed control strategy is based only on a basic two-motor imagery BCI, which enables more people to use it in real-life applications.
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.
Helmich, I; Lausberg, H
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
Melanie Rose Burke
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.
O. V. Korzhyk
Full Text Available The academic community is paying more and more attention to the question of the individual characteristics of the brain processes which ensure the manual motor programming of movements performed not only by the leading, but also by the subdominant hand. Researchers do not exclude the existence of the particular parameters of the human brain correlating with manual motor activities. This study involved 136 women at the age of 19–21 years. The testees were divided into two groups according to high and low values of the EEG modal α-frequency determined individually and in a motionless state. We evaluated the coherence status of the EEG frequency components in the motionless state and during movements performed by fingers of the subdominant (left hand in response to rhythmic sound signals. The testing stages involved the sequential execution of motor tasks including clamping and unclamping performed by the fingers of the subdominant hand (such as grasping movements without effort. The testees also performed fingering (a manual response to each stimulus at in different times and not by all the fingers of the hand simultaneously, but separately, one by one, in a given sequence. Clamping and unclamping was executed by the fingers subject to power loading the (additional load on the fingers being 10H. Execution of manual movements by means of the subdominant hand in response to the sensory signals was accompanied by an increase in coherence in the EEG frequency components, especially in the frontal, temporal, and parietal cortexes of the central areas. Women with a low individual α-rate of such a regularity had significantly increased scores at the high (α3-, β- frequencies of the EEG spectrum. At the same time, women in both groups mainly showed a decrease in the coherence coefficients of θ-, α1- and α3-activity in the frontal cortex leads in terms of the execution of the sequential finger movements and movements under power loading. The
Sollfrank, Teresa; Hart, Daniel; Goodsell, Rachel; Foster, Jonathan; Tan, Tele
A repetitive movement practice by motor imagery (MI) can influence motor cortical excitability in the electroencephalogram (EEG). This study investigated if a realistic visualization in 3D of upper and lower limb movements can amplify motor related potentials during subsequent MI. We hypothesized that a richer sensory visualization might be more effective during instrumental conditioning, resulting in a more pronounced event related desynchronization (ERD) of the upper alpha band (10-12 Hz) over the sensorimotor cortices thereby potentially improving MI based brain-computer interface (BCI) protocols for motor rehabilitation. The results show a strong increase of the characteristic patterns of ERD of the upper alpha band components for left and right limb MI present over the sensorimotor areas in both visualization conditions. Overall, significant differences were observed as a function of visualization modality (VM; 2D vs. 3D). The largest upper alpha band power decrease was obtained during MI after a 3-dimensional visualization. In total in 12 out of 20 tasks the end-user of the 3D visualization group showed an enhanced upper alpha ERD relative to 2D VM group, with statistical significance in nine tasks.With a realistic visualization of the limb movements, we tried to increase motor cortex activation during subsequent MI. The feedback and the feedback environment should be inherently motivating and relevant for the learner and should have an appeal of novelty, real-world relevance or aesthetic value (Ryan and Deci, 2000; Merrill, 2007). Realistic visual feedback, consistent with the participant's MI, might be helpful for accomplishing successful MI and the use of such feedback may assist in making BCI a more natural interface for MI based BCI rehabilitation.
Huttunen, P; Savinainen, A; Hänninen, Osmo; Myllylä, R
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.
Full Text Available Motor imagery-based brain-computer interfaces (BCI have shown potential for the rehabilitation of stroke patients; however, low performance has restricted their application in clinical environments. Therefore, this work presents the implementation of a BCI system, coupled to a robotic hand orthosis and driven by hand motor imagery of healthy subjects and the paralysed hand of stroke patients. A novel processing stage was designed using a bank of temporal filters, the common spatial pattern algorithm for feature extraction and particle swarm optimisation for feature selection. Offline tests were performed for testing the proposed processing stage, and results were compared with those computed with common spatial patterns. Afterwards, online tests with healthy subjects were performed in which the orthosis was activated by the system. Stroke patients’ average performance was 74.1 ± 11%. For 4 out of 6 patients, the proposed method showed a statistically significant higher performance than the common spatial pattern method. Healthy subjects’ average offline and online performances were of 76.2 ± 7.6% and 70 ± 6.7, respectively. For 3 out of 8 healthy subjects, the proposed method showed a statistically significant higher performance than the common spatial pattern method. System’s performance showed that it has a potential to be used for hand rehabilitation of stroke patients.
Wiemers, Michael; Fischer, Martin H
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.
Within the domain-general theory of language impairment, this study examined body posture and hand movement imitation in children with specific language impairment (SLI) and in their age-matched peers. Participants included 40 children with SLI (5 years 3 months to 6 years 10 months of age) and 40 children with typical language development (5…
van Houwelingen, J.; Schreven, S.; Smeets, J.J.B.; Clercx, H.J.H.; Beek, P.J.
A literature review is presented about the hydrodynamic effects of different hand and arm movements during swimming with the aim to identify lacunae in current methods and knowledge, and to distil practical guidelines for coaches and swimmers seeking to increase swimming speed. Experimental and
Bekkering, H.; Pratt, J.
Theories in motor control suggest that the parameters specified during the planning of goal-directed hand movements to a visual target are defined in spatial parameters like direction and amplitude. Recent findings in the visual attention literature, however, argue widely for early object-based
Full Text Available Eye and hand movement tracking has been proven to be a successful tool and is widely used to figure out characteristics of human cognition in language or visual processing (Just & Carpenter, 1976 Cognitive Psychology 8441–480. Eye movement has proven to be a successful measure to figure out characteristics of human language and visual processing (Rayner, 1998 Psychological Bulletin 124(3 372–422. Recently, mouse tracking was used for social-cognition-like categorization of sex-atypical faces and studying spoken-language processes (Magnuson, 2005 PNAS 102(28 9995–9996; Spivey et al., 2005 PNAS 102 10393–10398. Here, we present a framework that uses both eye gaze and hand movement simultaneously for analyzing the relation of them during memory retrieval. We tracked eye and mouse movements when the subject was watching a drama and playing a multimodal memory game (MMG, a cognitive task designed to investigate the recall memory mechanisms in watching video dramas (Zhang, 2009 AAAI 2009 Spring Symposium: Agents that Learn from Human Teachers 144–149. Experimental results show that eye tracking and mouse tracking provide complementary information about underlying cognitive processes. Also, we found some interesting patterns in eye-hand movement during multimodal memory recall.
Yu Wei; Yan Zixu; Ma Xiaohai; Zhang Zhaoqi; Lin Chongyu; Zang Yufeng; Weng Xuchu
Objective: To identify the neural substrates of voluntary movements of dominant and subdominant hands by using the whole-brain functional magnetic resonance imaging. Methods: Seven right-handed healthy volunteers were scanned at a Sonata 1.5 Tesla magnetic resonance imaging scanner (Siemens) while they were performing the visually instructive movement tasks with their right and left index fingers. Image data were co-registered to correct head motion, spatially normalized according to the standard coordinates, and spatially smoothed with isotopic Guassian Kernel. Statistical parametric maps (activation maps) for right and left hands were generated respectively by cross-correlation analysis. Results: Voluntary movements of the right/dominant hand mainly activated contralateral primary motor cortex (MI), bilateral supplementary motor area (SMA), bilateral second motor area (MII), and ipsilateral cerebellum, whereas movements of the left/subdominant hand additionally elicited activation in contralateral premotor area (PMC). Moreover, activation volumes in SMA and MII during movements of the subdominant hand were significantly larger than those during movements of the dominant hand. Conclusion: A large set of structures in the cerebral cortex and cerebellum is involved in voluntary movements, as revealed by whole brain-based fMRI. Movements of the subdominant hand are more dependent on higher control areas, such as SMA and PMC, comparing to movements of the dominant hand
Kalckert, Andreas; Ehrsson, H Henrik
The rubber hand illusion is a perceptual illusion in which a model hand is experienced as part of one's own body. In the present study we directly compared the classical illusion, based on visuotactile stimulation, with a rubber hand illusion based on active and passive movements. We examined the question of which combinations of sensory and motor cues are the most potent in inducing the illusion by subjective ratings and an objective measure (proprioceptive drift). In particular, we were interested in whether the combination of afferent and efferent signals in active movements results in the same illusion as in the purely passive modes. Our results show that the illusion is equally strong in all three cases. This demonstrates that different combinations of sensory input can lead to a very similar phenomenological experience and indicates that the illusion can be induced by any combination of multisensory information. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Erden, Mustafa Suphi; Billard, Aude
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.
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
Song, Weiguo; Francis, Joseph Thachil
Motor output mostly depends on sensory input, which also can be affected by action. To further our understanding of how tactile information is processed in the primary somatosensory cortex (S1) in dynamic environments, we recorded neural responses to tactile stimulation of the hand in three awake monkeys under arm/hand passive movement and rest. We found that neurons generally responded to tactile stimulation under both conditions and were modulated by movement: with a higher baseline firing rate, a suppressed peak rate, and a smaller dynamic range during passive movement than during rest, while the area under the response curve was stable across these two states. By using an information theory-based method, the mutual information between tactile stimulation and neural responses was quantified with rate and spatial coding models under the two conditions. The two potential encoding models showed different contributions depending on behavioral contexts. Tactile information encoded with rate coding from individual units was lower than spatial coding of unit pairs, especially during movement; however, spatial coding had redundant information between unit pairs. Passive movement regulated the mutual information, and such regulation might play different roles depending on the encoding strategies used. The underlying mechanisms of our observation most likely come from a bottom-up strategy, where neurons in S1 were regulated through the activation of the peripheral tactile/proprioceptive receptors and the interactions between these different types of information.
Popović Mirjana B.
Full Text Available INTRODUCTION An algorithm to study hand movements in patients with Parkinson's disease (PD who experience temporary, involuntary inability to move a hand have been developed. In literature, this rather enigmatic phenomenon has been described in gait, speech, handwriting and tapping, and noted as motor blocks (MB or freezing episodes. Freezing refers to transient periods in which the voluntary motor activity being attempted by an individual is paused. It is a sudden, unplanned state of immobility that appears to arise from deficits in initiating or simultaneously and sequentially executing movements, in correcting inappropriate movements or in planning movements. The clinical evaluation of motor blocks is difficult because of a variability both within and between individuals and relationship of blocks to time of drug ingestion. In literature the terms freezing, motor block or motor freezing are used in parallel. AIM In clinical settings classical manifestations of Parkinson's Disease (akinesia bradykinesia, rigidity, tremor, axial motor performance and postural instability are typically evaluated. Recently, in literature, new computerized methods are suggested for their objective assessment. We propose monitoring of motor blocks during hand movements to be integrated. For this purpose we have developed a simple method that comprises PC computer, digitizing board and custom made software. Movement analysis is "off line", and the result is the data that describe the number, duration and onset of motor blocks. METHOD Hand trajectories are assessed during simple volitional self paced point-to-point planar hand movement by cordless magnetic mouse on a digitizing board (Drawing board III, 305 x 457 mm, GTCO Cal Comp Inc, Fig. 1. Testing included 8 Parkinsonian patients and 8 normal healthy controls, age matched, with unknown neurologic motor or sensory disorders, Table 1. Three kinematic indicators of motor blocks: 1 duration (MBTJ; 2 onset (t%; and 3
Gonzalez, Jania; Ding, Lei
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 (pEEG 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. PMID:24416360
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.
Dennis, Andrea; Bosnell, Rose; Dawes, Helen; Howells, Ken; Cockburn, Janet; Kischka, Udo; Matthews, Paul; Johansen-Berg, Heidi
Stroke patients often have difficulties in simultaneously performing a motor and cognitive task. Functional imaging studies have shown that movement of an affected hand after stroke is associated with increased activity in multiple cortical areas, particularly in the contralesional hemisphere. We hypothesized patients for whom executing simple movements demands greater selective attention will show greater brain activity during movement. Eight chronic stroke patients performed a behavioral interference test using a visuo-motor tracking with and without a simultaneous cognitive task. The magnitude of behavioral task decrement under cognitive motor interference (CMI) conditions was calculated for each subject. Functional MRI was used to assess brain activity in the same patients during performance of a visuo-motor tracking task alone; correlations between CMI score and movement-related brain activation were then explored. Movement-related activation in the dorsal precentral gyrus of the contralesional hemisphere correlated strongly and positively with CMI score (r(2) at peak voxel=0.92; Pstroke. The results emphasize the importance of considering cognitive context when interpreting brain activity patterns and provide a rationale for further evaluation of integrated cognitive and movement interventions for rehabilitation in stroke.
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.
Full Text Available Levodopa (L-dopa effects on the cardinal and axial symptoms of Parkinson's disease (PD differ greatly, leading to therapeutic challenges for managing the disabilities in this patient's population. In this context, we studied the cerebral networks associated with the production of a unilateral hand movement, speech production, and a task combining both tasks in 12 individuals with PD, both off and on levodopa (L-dopa. Unilateral hand movements in the off medication state elicited brain activations in motor regions (primary motor cortex, supplementary motor area, premotor cortex, cerebellum, as well as additional areas (anterior cingulate, putamen, associative parietal areas; following L-dopa administration, the brain activation profile was globally reduced, highlighting activations in the parietal and posterior cingulate cortices. For the speech production task, brain activation patterns were similar with and without medication, including the orofacial primary motor cortex (M1, the primary somatosensory cortex and the cerebellar hemispheres bilaterally, as well as the left- premotor, anterior cingulate and supramarginal cortices. For the combined task off L-dopa, the cerebral activation profile was restricted to the right cerebellum (hand movement, reflecting the difficulty in performing two movements simultaneously in PD. Under L-dopa, the brain activation profile of the combined task involved a larger pattern, including additional fronto-parietal activations, without reaching the sum of the areas activated during the simple hand and speech tasks separately. Our results question both the role of the basal ganglia system in speech production and the modulation of task-dependent cerebral networks by dopaminergic treatment.
Roze, Emmanuel; Cochen, Valérie; Sangla, Sophie; Bienvenu, Thierry; Roubergue, Anne; Leu-Semenescu, Smaranda; Vidaihet, Marie
Rett syndrome is an X-linked neurodevelopmental disorder resulting in profound psychomotor retardation. It is usually diagnosed by a pediatrician or pediatric neurologist. Adult neurologists may, therefore, overlook the possibility of Rett syndrome in women with psychomotor retardation of unknown etiology. We report the case of a woman diagnosed with Rett syndrome at age 49 years. This report emphasizes the diagnostic value of movement disorders, including hand stereotypies, Parkinsonism, and dystonia, in adults with Rett syndrome.
Pham, Hai Trieu; Pathirana, Pubudu N; Caelli, Terry
The measurement of the range of hand joint movement is an essential part of clinical practice and rehabilitation. Current methods use three finger joint declination angles of the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints. In this paper we propose an alternate form of measurement for the finger movement. Using the notion of reachable space instead of declination angles has significant advantages. Firstly, it provides a visual and quantifiable method that therapists, insurance companies and patients can easily use to understand the functional capabilities of the hand. Secondly, it eliminates the redundant declination angle constraints. Finally, reachable space, defined by a set of reachable fingertip positions, can be measured and constructed by using a modern camera such as Creative Senz3D or built-in hand gesture sensors such as the Leap Motion Controller. Use of cameras or optical-type sensors for this purpose have considerable benefits such as eliminating and minimal involvement of therapist errors, non-contact measurement in addition to valuable time saving for the clinician. A comparison between using declination angles and reachable space were made based on Hume's experiment on functional range of movement to prove the efficiency of this new approach.
Full Text Available Timing of sequential movements is altered in Parkinson disease (PD. Whether timing deficits in internally generated sequential movements in PD depends also on difficulties in motor planning, rather than merely on a defective ability to materially perform the planned movement is still undefined. To unveil this issue, we adopted a modified version of an established test for motor timing, i.e. the synchronization-continuation paradigm, by introducing a motor imagery task. Motor imagery is thought to involve mainly processes of movement preparation, with reduced involvement of end-stage movement execution-related processes. Fourteen patients with PD and twelve matched healthy volunteers were asked to tap in synchrony with a metronome cue (SYNC and then, when the tone stopped, to keep tapping, trying to maintain the same rhythm (CONT-EXE or to imagine tapping at the same rhythm, rather than actually performing it (CONT-MI. We tested both a sub-second and a supra-second inter-stimulus interval between the cues. Performance was recorded using a sensor-engineered glove and analyzed measuring the temporal error and the interval reproduction accuracy index. PD patients were less accurate than healthy subjects in the supra-second time reproduction task when performing both continuation tasks (CONT-MI and CONT-EXE, whereas no difference was detected in the synchronization task and on all tasks involving a sub-second interval. Our findings suggest that PD patients exhibit a selective deficit in motor timing for sequential movements that are separated by a supra-second interval and that this deficit may be explained by a defect of motor planning. Further, we propose that difficulties in motor planning are of a sufficient degree of severity in PD to affect also the motor performance in the supra-second time reproduction task.
Kearns, Michelle; Engelhard, Iris M
A principle characteristic of public speaking anxiety relates to intrusive mental images of potential future disasters. Previous research has found that the self-reported emotionality of such "flashforwards" can be reduced by a cognitively demanding, dual-task (e.g., making eye movements) performed whilst holding the mental image in-mind. The outcome measure in these earlier studies was participants' self-reported emotional intensity of the mental image. The current study (N = 34) explored whether an objective measure of emotionality would yield similar results in students with public speaking anxiety. A script-driven imagery procedure was used to measure psychophysiological responsivity to an audio script depicting a feared (public speaking) scenario before and after an eye movement intervention. Relative to the control condition (imagery only), those who made eye movements whilst holding a mental image of this scenario in-mind demonstrated a significant decrease in heart rate, which acted as a measure of emotionality. These findings add to a previous body of research demonstrating the beneficial qualities of dual-tasks and their potential for treatment of both past and future-oriented anxieties.
Bobrova, E V; Liakhovetskiĭ, V A; Borshchevskaia, E R
The dependence of errors during reproduction of a sequence of hand movements without visual feedback on the previous right- and left-hand performance ("prehistory") and on positions in space of sequence elements (random or ordered by the explicit rule) was analyzed. It was shown that the preceding information about the ordered positions of the sequence elements was used during right-hand movements, whereas left-hand movements were performed with involvement of the information about the random sequence. The data testify to a central mechanism of the analysis of spatial structure of sequence elements. This mechanism activates movement coding specific for the left hemisphere (vector coding) in case of an ordered sequence structure and positional coding specific for the right hemisphere in case of a random sequence structure.
Stock, Vinicius N; Balbinot, Alexandre
Brain-computer interfaces (BCI) provide means of communications and control, in assistive technology, which do not require motor activity from the user. The goal of this study is to promote classification of two types of imaginary movements, left and right hands, in an EMOTIV cap based system, using the Naïve Bayes classifier. A preliminary analysis with respect to results obtained by other experiments in this field is also conducted. Processing of the electroencephalography (EEG) signals is done applying Common Spatial Pattern filters. The EPOC electrodes cap is used for EEG acquisition, in two test subjects, for two distinct trial formats. The channels picked are FC5, FC6, P7 and P8 of the 10-20 system, and a discussion about the differences of using C3, C4, P3 and P4 positions is proposed. Dataset 3 of the BCI Competition II is also analyzed using the implemented algorithms. The maximum classification results for the proposed experiment and for the BCI Competition dataset were, respectively, 79% and 85% The conclusion of this study is that the picked positions for electrodes may be applied for BCI systems with satisfactory classification rates.
Peng, Zhen; Braun, Daniel A.
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
Full Text Available Objectives: This study describes a single subject design (ABA that shows the effective use of constraint induced movement therapy in improvement of quality and performance of in-hand manipulation skills for a 10 year old boy and a 9 years old girl with hemiplegic cerebral palsy, as Dickerson (2007 showed it in arm movement and function. Methods: To determine the effectiveness of CIMT by the use of C-statistic analysis and visual analysis. Approach: The first step was to design a child friendly group activity and home based intervention program through occupation. The possible effectiveness of CIMT was evaluated by daily measurements and video recording of 6 sub skills of in-hand manipulation according to Pont category (2009 in defined activity. Results: For making the treatment more cost effective, families can produce a simple clinical setting at home and participate in their child treatment plan actively. Discussion: A client center intervention will facilitate the use and quality of fingers and hand motion. Also a group activity can motivate participants to participate more and better.
Yaacoub, Charles; Mhanna, Georges; Rihana, Sandy
Electroencephalography is a non-invasive measure of the brain electrical activity generated by millions of neurons. Feature extraction in electroencephalography analysis is a core issue that may lead to accurate brain mental state classification. This paper presents a new feature selection method that improves left/right hand movement identification of a motor imagery brain-computer interface, based on genetic algorithms and artificial neural networks used as classifiers. Raw electroencephalography signals are first preprocessed using appropriate filtering. Feature extraction is carried out afterwards, based on spectral and temporal signal components, and thus a feature vector is constructed. As various features might be inaccurate and mislead the classifier, thus degrading the overall system performance, the proposed approach identifies a subset of features from a large feature space, such that the classifier error rate is reduced. Experimental results show that the proposed method is able to reduce the number of features to as low as 0.5% (i.e., the number of ignored features can reach 99.5%) while improving the accuracy, sensitivity, specificity, and precision of the classifier.
Full Text Available Electroencephalography is a non-invasive measure of the brain electrical activity generated by millions of neurons. Feature extraction in electroencephalography analysis is a core issue that may lead to accurate brain mental state classification. This paper presents a new feature selection method that improves left/right hand movement identification of a motor imagery brain-computer interface, based on genetic algorithms and artificial neural networks used as classifiers. Raw electroencephalography signals are first preprocessed using appropriate filtering. Feature extraction is carried out afterwards, based on spectral and temporal signal components, and thus a feature vector is constructed. As various features might be inaccurate and mislead the classifier, thus degrading the overall system performance, the proposed approach identifies a subset of features from a large feature space, such that the classifier error rate is reduced. Experimental results show that the proposed method is able to reduce the number of features to as low as 0.5% (i.e., the number of ignored features can reach 99.5% while improving the accuracy, sensitivity, specificity, and precision of the classifier.
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.
Wu, Yazhou; He, Qinghua; Huang, Hua; Zhang, Ling; Zhuo, Yu; Xie, Qi; Wu, Baoming
This is a research carried out to explore a pragmatic way of BCI based imaging movement, i. e. to extract the feature of EEG for reflecting different thinking by searching suitable methods of signal extraction and recognition algorithm processing, to boost the recognition rate of communication for BCI system, and finally to establish a substantial theory and experimental support for BCI application. In this paper, different mental tasks for imaging left-right hands movement from 6 subjects were studied in three different time sections (hint keying at 2s, 1s and 0s after appearance of arrow). Then we used wavelet analysis and Feed-forward Back-propagation Neural Network (BP-NN) method for processing and analyzing the experimental data of off-line. Delay time delta t2, delta t1 and delta t0 for all subjects in the three different time sections were analyzed. There was significant difference between delta to and delta t2 or delta t1 (P0.05). The average results of recognition rate were 65%, 86.67% and 72%, respectively. There were obviously different features for imaging left-right hands movement about 0.5-1s before actual movement; these features displayed significant difference. We got higher recognition rate of communication under the hint keying at about 1s after the appearance of arrow. These showed the feasibility of using the feature signals extracted from the project as the external control signals for BCI system, and demon strated that the project provided new ideas and methods for feature extraction and classification of mental tasks for BCI.
de Vries, Paulien M.; de Jong, Bauke M.; Bohning, Daryl E.; Walker, John A.; George, Mark S.; Leenders, Klaus L.
The left parietal cortex contributes to goal-directed hand movement. In this study, we targeted this region with transcranial magnetic stimulation (TMS) to assess the effects on a wider distributed circuitry related to motor control. Ten healthy subjects underwent 3 Tesla functional magnetic
Littel, Marianne; van den Hout, Marcel A; Engelhard, Iris M
Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. During this treatment, patients recall traumatic memories while making horizontal eye movements (EM). Studies have shown that EM not only desensitize negative memories but also positive memories and imagined events. Substance use behavior and craving are maintained by maladaptive memory associations and visual imagery. Preliminary findings have indicated that these mental images can be desensitized by EMDR techniques. We conducted two proof-of-principle studies to investigate whether EM can reduce the sensory richness of substance-related mental representations and accompanying craving levels. We investigated the effects of EM on (1) vividness of food-related mental imagery and food craving in dieting and non-dieting students and (2) vividness of recent smoking-related memories and cigarette craving in daily smokers. In both experiments, participants recalled the images while making EM or keeping eyes stationary. Image vividness and emotionality, image-specific craving and general craving were measured before and after the intervention. As a behavioral outcome measure, participants in study 1 were offered a snack choice at the end of the experiment. Results of both experiments showed that image vividness and craving increased in the control condition but remained stable or decreased after the EM intervention. EM additionally reduced image emotionality (experiment 2) and affected behavior (experiment 1): participants in the EM condition were more inclined to choose healthy over unhealthy snack options. In conclusion, these data suggest that EM can be used to reduce intensity of substance-related imagery and craving. Although long-term effects are yet to be demonstrated, the current studies suggest that EM might be a useful technique in addiction treatment.
Full Text Available Eye movement desensitization and reprocessing (EMDR is an effective treatment for posttraumatic stress disorder. During this treatment, patients recall a traumatic memory while making horizontal eye movements (EM. Studies have shown that EM not only desensitize negative memories, but also positive memories and imagined events. Substance use behavior and craving are maintained by maladaptive memory associations and visual imagery. Preliminary findings have indicated that these mental images can be desensitized by EMDR techniques. We conducted two proof-of-principle studies to investigate whether EM can reduce the sensory richness of substance-related mental representations and accompanying craving levels. We investigated the effects of EM on 1 vividness of food-related mental imagery and food craving in dieting and non-dieting students, and 2 vividness of recent smoking-related memories and cigarette craving in daily smokers. In both experiments, participants recalled the images while making EM or keeping eyes stationary. Image vividness and emotionality, image-specific craving and general craving were measured before and after the intervention. As a behavioral outcome measure, participants in study 1 were offered a snack choice at the end of the experiment.Results of both experiments showed that image vividness and craving increased in the control condition, but remained stable or decreased after the EM intervention. EM additionally reduced image emotionality (exp 2, and affected behavior (exp 1: participants in the EM condition were more inclined to choose healthy over unhealthy snack options. In conclusion, the data suggest that EM can be used to reduce intensity of substance related imagery and craving. Although long-term effects are yet to be demonstrated, the current studies suggest that EM might be a useful technique in addiction treatment.
Keller, Peter E.; Dalla Bella, Simone; Koch, Iring
The role of anticipatory auditory imagery in music-like sequential action was investigated by examining timing accuracy and kinematics using a motion capture system. Musicians responded to metronomic pacing signals by producing three unpaced taps on three vertically aligned keys at the given tempo. Taps triggered tones in two out of three blocked…
Gopal, Atul; Murthy, Aditya
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. Copyright © 2016 the American Physiological Society.
Yang, Ruiduo; Sarkar, Sudeep; Loeding, Barbara
We consider two crucial problems in continuous sign language recognition from unaided video sequences. At the sentence level, we consider the movement epenthesis (me) problem and at the feature level, we consider the problem of hand segmentation and grouping. We construct a framework that can handle both of these problems based on an enhanced, nested version of the dynamic programming approach. To address movement epenthesis, a dynamic programming (DP) process employs a virtual me option that does not need explicit models. We call this the enhanced level building (eLB) algorithm. This formulation also allows the incorporation of grammar models. Nested within this eLB is another DP that handles the problem of selecting among multiple hand candidates. We demonstrate our ideas on four American Sign Language data sets with simple background, with the signer wearing short sleeves, with complex background, and across signers. We compared the performance with Conditional Random Fields (CRF) and Latent Dynamic-CRF-based approaches. The experiments show more than 40 percent improvement over CRF or LDCRF approaches in terms of the frame labeling rate. We show the flexibility of our approach when handling a changing context. We also find a 70 percent improvement in sign recognition rate over the unenhanced DP matching algorithm that does not accommodate the me effect.
Stins, J.F.; Schneider, I.K.; Koole, S.L.; Beek, P.J.
The present study examined the differential effects of kinesthetic imagery (first person perspective) and visual imagery (third person perspective) on postural sway during quiet standing. Based on an embodied cognition perspective, the authors predicted that kinesthetic imagery would lead to
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.
Full Text Available We present an approach for quantitative assessment of the arm/hand movements in patients with Parkinson’s disease (PD, from sensor data acquired with a wearable, wireless armband device (Myo sensor. We propose new Movement Performance Indicators that can be adopted by practitioners for the quantitative evaluation of motor performance and support their clinical evaluations. In addition, specific Movement Performance Indicators can indicate the presence of the bradykinesia symptom. The study includes seventeen PD patients and sixteen age-matched controls. A set of representative arm/hand movements is defined under the supervision of movement disorder specialist. In order to assist the evaluations, and for progress monitoring purposes, as well as for assessing the amount of bradykinesia in PD, a total set of 84 Movement Performance Indicators are computed from the sensor readings. Subsequently, we investigate whether wireless armband device, with the use of the proposed Movement Performance Indicators can be utilized: (1 for objective and precise quantitative evaluation of the arm/hand movements of Parkinson’s patients, (2 for assessment of the bradykinesia motor symptom, and (3 as an adequate low-cost alternative for the sensor glove. We conducted extensive analysis of proposed Movement Performance Indicators and results are indicating following clinically relevant characteristics: (i adequate reliability as measured by ICC; (ii high accuracy in discrimination between the patients and controls, and between the disease stages (support to disease diagnosis and progress monitoring, respectively; (iii substantial difference in comparison between the left-hand and the right-hand movements across controls and patients, as well as between disease stage groups; (iv statistically significant correlation with clinical scales (tapping test and UPDRS-III Motor Score; and (v quantitative evaluation of bradykinesia symptom. Results suggest that the proposed
Full Text Available Tohshin Go1, Asako Mitani21Center for Baby Science, Doshisha University, Kizugawa, Kyoto, Japan; 2Independent Music Therapist (Poco A Poco Music Room, Tokyo, JapanAbstract: Patients with Rett syndrome are known to respond well to music irrespective of their physical and verbal disabilities. Therefore, the relationship between auditory rhythm and their behavior was investigated employing a two-dimensional motion analysis system. Ten female patients aged from three to 17 years were included. When music with a simple regular rhythm started, body rocking appeared automatically in a back and forth direction in all four patients who showed the same rocking motion as their stereotyped movement. Through this body rocking, voluntary movement of the hand increased gradually, and finally became sufficient to beat a tambourine. However, the induction of body rocking by music was not observed in the other six patients who did not show stereotyped body rocking in a back and forth direction. When the music stopped suddenly, voluntary movement of the hand disappeared. When the music changed from a simple regular rhythm to a continuous tone without an auditory rhythm, the periodic movement of both the hand and body prolonged. Auditory rhythm shows a close relationship with body movement and facilitates synchronized body movement. This mechanism was demonstrated to be preserved in some patients with Rett syndrome, and stimulation with music could be utilized for their rehabilitation.Keywords: Rett syndrome, music, auditory rhythm, stereotyped movement, body rocking, voluntary movement
Dalawis, Rando C.; Olayao, Kenneth Deniel R.; Ramos, Evan Geoffrey I.; Samonte, Mary Jane C.
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.
Blesić, S.; Stratimirović, Dj.; Milošević, S.; Marić, J.; Kostić, V.; Ljubisavljević, M.
In this paper we have used the Wavelet Transform (WT) and the Detrended Fluctuation Analysis (DFA) methods to analyze hand tremor movements in essential tremor (ET), in two different recording conditions (before and after the addition of wrist-cuff load). We have analyzed the time series comprised of peak-to-peak (PtP) intervals, extracted from regions around the first three main frequency components of the power spectra (PwS) of the recorded tremors, in order to substantiate results related to the effects of load on ET, to distinguish between multiple sources of ET, and to separate the influence of peripheral factors on ET. Our results show that, in ET, the dynamical characteristics, that is, values of respective scaling exponents, of the main frequency component of recorded tremors change after the addition of load. Our results also show that in all the observed cases the scaling behavior of the calculated functions changes as well-the calculated WT scalegrams and DFA functions display a shift in the position of the crossover when the load is added. We conclude that the difference in behavior of the WT and DFA functions between different conditions in ET could be associated with the expected pathology in ET, or with some additional mechanism that controls movements in ET patients, and causes the observed changes in scaling behavior.
Hogrefe, Katharina; Rein, Robert; Skomroch, Harald; Lausberg, Hedda
Persons with brain damage show deviant patterns of co-speech hand movement behaviour in comparison to healthy speakers. It has been claimed by several authors that gesture and speech rely on a single production mechanism that depends on the same neurological substrate while others claim that both modalities are closely related but separate production channels. Thus, findings so far are contradictory and there is a lack of studies that systematically analyse the full range of hand movements that accompany speech in the condition of brain damage. In the present study, we aimed to fill this gap by comparing hand movement behaviour in persons with unilateral brain damage to the left and the right hemisphere and a matched control group of healthy persons. For hand movement coding, we applied Module I of NEUROGES, an objective and reliable analysis system that enables to analyse the full repertoire of hand movements independent of speech, which makes it specifically suited for the examination of persons with aphasia. The main results of our study show a decreased use of communicative conceptual gestures in persons with damage to the right hemisphere and an increased use of these gestures in persons with left brain damage and aphasia. These results not only suggest that the production of gesture and speech do not rely on the same neurological substrate but also underline the important role of right hemisphere functioning for gesture production. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bock, Otmar; Schott, Nadja; Papaxanthis, Charalambos
Before participating in a space mission, astronauts undergo parabolic-flight and underwater training to facilitate their subsequent adaptation to weightlessness. Unfortunately, similar training methods can’t be used to prepare re-adaptation to planetary gravity. Here, we propose a quick, simple and inexpensive approach that could be used to prepare astronauts both for the absence and for the renewed presence of gravity. This approach is based on motor imagery (MI), a process in which actions are produced in working memory without any overt output. Training protocols based on MI have repeatedly been shown to modify brain circuitry and to improve motor performance in healthy young adults, healthy seniors and stroke victims, and are routinely used to optimize performance of elite athletes. We propose to use similar protocols preflight, to prepare for weightlessness, and late inflight, to prepare for landing. PMID:26042004
Full Text Available Before participating in a space mission, astronauts undergo parabolic-flight and underwater training to facilitate their subsequent adaptation to weightlessness. Unfortunately, similar training methods can’t be used to prepare re-adaptation to planetary gravity. Here, we propose a quick, simple and inexpensive approach that could be used to prepare astronauts both for the absence and for the renewed presence of gravity. This approach is based on motor imagery (MI, a process in which actions are produced in working memory without any overt output. Training protocols based on MI have repeatedly been shown to modify brain circuitry and to improve motor performance in healthy young adults, healthy seniors and stroke victims, and are routinely used to optimize performance of elite athletes. We propose to use similar protocols preflight, to prepare for weightlessness, and late inflight, to prepare for landing.
Burin, Dalila; Livelli, Alessandro; Garbarini, Francesca; Fossataro, Carlotta; Folegatti, Alessia; Gindri, Patrizia; Pia, Lorenzo
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.
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.
Full Text Available The myoelectric prosthetic hand is a powerful tool developed to help people with upper limb loss restore the functions of a biological hand. Recognizing multiple hand motions from only a few electromyography (EMG sensors is one of the requirements for the development of prosthetic hands with high level of usability. This task is highly challenging because both classification rate and misclassification rate worsen with additional hand motions. This paper presents a signal processing technique that uses spectral features and an artificial neural network to classify 17 voluntary movements from EMG signals. The main highlight will be on the use of a small set of low-cost EMG sensor for classification of a reasonably large number of hand movements. The aim of this work is to extend the capabilities to recognize and produce multiple movements beyond what is currently feasible. This work will also show and discuss about how tailoring the number of hand motions for a specific task can help develop a more reliable prosthetic hand system. Online classification experiments have been conducted on seven male and five female participants to evaluate the validity of the proposed method. The proposed algorithm achieves an overall correct classification rate of up to 83%, thus, demonstrating the potential to classify 17 movements from 6 EMG sensors. Furthermore, classifying 9 motions using this method could achieve an accuracy of up to 92%. These results show that if the prosthetic hand is intended for a specific task, limiting the number of motions can significantly increase the performance and usability.
Go, Tohshin; Mitani, Asako
Patients with Rett syndrome are known to respond well to music irrespective of their physical and verbal disabilities. Therefore, the relationship between auditory rhythm and their behavior was investigated employing a two-dimensional motion analysis system. Ten female patients aged from three to 17 years were included. When music with a simple regular rhythm started, body rocking appeared automatically in a back and forth direction in all four patients who showed the same rocking motion as their stereotyped movement. Through this body rocking, voluntary movement of the hand increased gradually, and finally became sufficient to beat a tambourine. However, the induction of body rocking by music was not observed in the other six patients who did not show stereotyped body rocking in a back and forth direction. When the music stopped suddenly, voluntary movement of the hand disappeared. When the music changed from a simple regular rhythm to a continuous tone without an auditory rhythm, the periodic movement of both the hand and body prolonged. Auditory rhythm shows a close relationship with body movement and facilitates synchronized body movement. This mechanism was demonstrated to be preserved in some patients with Rett syndrome, and stimulation with music could be utilized for their rehabilitation.
Wertheim, E H; Habib, C; Cumming, G
Bandler and Grinder's hypothesis that eye-movements reflect sensory processing was examined. 28 volunteers first memorized and then recalled visual, auditory, and kinesthetic stimuli. Changes in eye-positions during recall were videotaped and categorized by two raters into positions hypothesized by Bandler and Grinder's model to represent visual, auditory, and kinesthetic recall. Planned contrast analyses suggested that visual stimulus items, when recalled, elicited significantly more upward eye-positions and stares than auditory and kinesthetic items. Auditory and kinesthetic items, however, did not elicit more changes in eye-position hypothesized by the model to represent auditory and kinesthetic recall, respectively.
Lauritzen, M; Henriksen, L; Lassen, N A
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...... motor area on both sides by 34 +/- 15% (p less than 0.025)....
Full Text Available In this paper, we propose a navigation approach for smartphones that enables visitors of major events to avoid crowded areas or narrow streets and to navigate out of dense crowds quickly. Two types of sensor data are integrated. Real-time optical images acquired and transmitted by an airborne camera system are used to compute an estimation of a crowd density map. For this purpose, a patch-based approach with a Gabor filter bank for texture classification in combination with an interest point detector and a smoothing function is applied. Furthermore, the crowd density is estimated based on location and movement speed of in situ smartphone measurements. This information allows for the enhancement of the overall crowd density layer. The composed density information is input to a least-cost routing workflow. Two possible use cases are presented, namely (i an emergency application and (ii a basic routing application. A prototypical implementation of the system is conducted as proof of concept. Our approach is capable of increasing the security level for major events. Visitors are able to avoid dense crowds by routing around them, while security and rescue forces are able to find the fastest way into the crowd.
Samuel C. Colachis
Full Text Available Individuals with tetraplegia identify restoration of hand function as a critical, unmet need to regain their independence and improve quality of life. Brain-Computer Interface (BCI-controlled Functional Electrical Stimulation (FES technology addresses this need by reconnecting the brain with paralyzed limbs to restore function. In this study, we quantified performance of an intuitive, cortically-controlled, transcutaneous FES system on standardized object manipulation tasks from the Grasp and Release Test (GRT. We found that a tetraplegic individual could use the system to control up to seven functional hand movements, each with >95% individual accuracy. He was able to select one movement from the possible seven movements available to him and use it to appropriately manipulate all GRT objects in real-time using naturalistic grasps. With the use of the system, the participant not only improved his GRT performance over his baseline, demonstrating an increase in number of transfers for all objects except the Block, but also significantly improved transfer times for the heaviest objects (videocassette (VHS, Can. Analysis of underlying motor cortex neural representations associated with the hand grasp states revealed an overlap or non-separability in neural activation patterns for similarly shaped objects that affected BCI-FES performance. These results suggest that motor cortex neural representations for functional grips are likely more related to hand shape and force required to hold objects, rather than to the objects themselves. These results, demonstrating multiple, naturalistic functional hand movements with the BCI-FES, constitute a further step toward translating BCI-FES technologies from research devices to clinical neuroprosthetics.
Frolov, A. A.; Húsek, Dušan; Biryukova, E. V.; Bobrov, P.; Mokienko, O.; Alexandrov, A.V.
Roč. 27, č. 1 (2017), s. 107-137 ISSN 1210-0552 Grant - others:Russian Ministry of Education and Science(RU) RFMEFI60715X0128 Institutional support: RVO:67985807 Keywords : brain computer interface * motor imagery * post-stroke and post-traumatic patients * arm and hand exoskeleton * proportional derivative controller * motor synergy * clinical application Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 0.394, year: 2016
Lee, Dong-Hoon; Lee, Do-Wan; Han, Bong-Soo
The purpose of this study is to elucidate the symmetrical characteristics of corticospinal tract (CST) related with hand movement in bilateral hemispheres using probabilistic fiber tracking method. Seventeen subjects were participated in this study. Fiber tracking was performed with 2 regions of interest, hand activated functional magnetic resonance imaging (fMRI) results and pontomedullary junction in each cerebral hemisphere. Each subject's extracted fiber tract was normalized with a brain template. To measure the symmetrical distributions of the CST related with hand movement, the laterality and anteriority indices were defined in upper corona radiata (CR), lower CR, and posterior limb of internal capsule. The measured laterality and anteriority indices between the hemispheres in each different brain location showed no significant differences with P the measured indices among 3 different brain locations in each cerebral hemisphere with P the hand CST had symmetric structures in bilateral hemispheres. The probabilistic fiber tracking with fMRI approach demonstrated that the hand CST can be successfully extracted regardless of crossing fiber problem. Our analytical approaches and results seem to be helpful for providing the database of CST somatotopy to neurologists and clinical researches.
Zhang, Jiang; Li, Yuyao; Chen, Huafu; Ding, Jurong; Yuan, Zhen
In this study, small-world network analysis was performed to identify the similarities and differences between functional brain networks for right- and left-hand motor imageries (MIs). First, Pearson correlation coefficients among the nodes within the functional brain networks from healthy subjects were calculated. Then, small-world network indicators, including the clustering coefficient, the average path length, the global efficiency, the local efficiency, the average node degree, and the small-world index, were generated for the functional brain networks during both right- and left-hand MIs. We identified large differences in the small-world network indicators between the functional networks during MI and in the random networks. More importantly, the functional brain networks underlying the right- and left-hand MIs exhibited similar small-world properties in terms of the clustering coefficient, the average path length, the global efficiency, and the local efficiency. By contrast, the right- and left-hand MI brain networks showed differences in small-world characteristics, including indicators such as the average node degree and the small-world index. Interestingly, our findings also suggested that the differences in the activity intensity and range, the average node degree, and the small-world index of brain networks between the right- and left-hand MIs were associated with the asymmetry of brain functions.
Godfrey, Sasha Blue; Holley, Rahsaan J; Lum, Peter S
The goals of this pilot study were to quantify the clinical benefits of using the Hand Exoskeleton Rehabilitation Robot for hand rehabilitation after stroke and to determine the population best served by this intervention. Nine subjects with chronic stroke (one excluded from analysis) completed 18 sessions of training with the Hand Exoskeleton Rehabilitation Robot and a preevaluation, a postevaluation, and a 90-day clinical evaluation. Overall, the subjects improved in both range of motion and clinical measures. Compared with the preevaluation, the subjects showed significant improvements in range of motion, grip strength, and the hand component of the Fugl-Meyer (mean changes, 6.60 degrees, 8.84 percentage points, and 1.86 points, respectively). A subgroup of six subjects exhibited lower tone and received a higher dosage of training. These subjects had significant gains in grip strength, the hand component of the Fugl-Meyer, and the Action Research Arm Test (mean changes, 8.42 percentage points, 2.17 points, and 2.33 points, respectively). Future work is needed to better manage higher levels of hypertonia and provide more support to subjects with higher impairment levels; however, the current results support further study into the Hand Exoskeleton Rehabilitation Robot treatment.
Kamrunnahar, M; Schiff, S J
We here investigated a non-linear ensemble Kalman filter (SPKF) application to a motor imagery brain computer interface (BCI). A square root central difference Kalman filter (SR-CDKF) was used as an approach for brain state estimation in motor imagery task performance, using scalp electroencephalography (EEG) signals. Healthy human subjects imagined left vs. right hand movements and tongue vs. bilateral toe movements while scalp EEG signals were recorded. Offline data analysis was conducted for training the model as well as for decoding the imagery movements. Preliminary results indicate the feasibility of this approach with a decoding accuracy of 78%-90% for the hand movements and 70%-90% for the tongue-toes movements. Ongoing research includes online BCI applications of this approach as well as combined state and parameter estimation using this algorithm with different system dynamic models.
Biegstraaten, Marianne; Smeets, Jeroen B J; Brenner, Eli
A pointing movement is executed faster when a subject is allowed to stop at the first target than when the subject has to proceed to a second target ("one-target advantage"). Our hypothesis was that this is because the impact at the target helps to stop the finger when the finger does not have to
Kazemi, Hamed; Kearney, Robert E; Milner, Theodore E
The goal of this study was to investigate the effect of speed on patterns of grip forces during twisting movement involving forearm supination against a torsional load (combined elastic and inertial load). For slow and moderate speed rotations, the grip force increased linearly with load torque. However, for fast rotations in which the contribution of the inertia to load torque was significantly greater than slower movements, the grip force-load torque relationship could be segmented into two phases: a linear ascending phase corresponding to the acceleration part of the movement followed by a plateau during deceleration. That is, during the acceleration phase, the grip force accurately tracked the combined elastic and inertial load. However, the coupling between grip force and load torque was not consistent during the deceleration phase of the movement. In addition, as speed increased, both the position and the force profiles became smoother. No differences in the baseline grip force, safety margin to secure the grasp during hold phase or the overall change in grip force were observed across different speeds.
Mutsaarts, M.J.H.; Steenbergen, B.; Bekkering, H.
It is generally assumed that movements of a part of the body (e.g., hands) are simulated in motor imagery (MI) tasks. This is evidenced by a linear increase in reaction time as a function of the angular rotation of the stimulus. Under the assumption that MI plays a critical role for anticipatory
Reichenbach, Alexandra; Thielscher, Axel; Peer, Angelika
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...
Bek, Judith; Poliakoff, Ellen; Marshall, Hannah; Trueman, Sophie; Gowen, Emma
Action observation activates brain areas involved in performing the same action and has been shown to increase motor learning, with potential implications for neurorehabilitation. Recent work indicates that the effects of action observation on movement can be increased by motor imagery or by directing attention to observed actions. In voluntary imitation, activation of the motor system during action observation is already increased. We therefore explored whether imitation could be further enhanced by imagery or attention. Healthy participants observed and then immediately imitated videos of human hand movement sequences, while movement kinematics were recorded. Two blocks of trials were completed, and after the first block participants were instructed to imagine performing the observed movement (Imagery group, N = 18) or attend closely to the characteristics of the movement (Attention group, N = 15), or received no further instructions (Control group, N = 17). Kinematics of the imitated movements were modulated by instructions, with both Imagery and Attention groups being closer in duration, peak velocity and amplitude to the observed model compared with controls. These findings show that both attention and motor imagery can increase the accuracy of imitation and have implications for motor learning and rehabilitation. Future work is required to understand the mechanisms by which these two strategies influence imitation accuracy.
Smith, Charles D.; Walton, Ashley; Slevin, John T.; Gerhardt, Greg A.; Umberger, Gloria; Smoot, Kyle; Schulze, Emily; Gash, Don
The human movement analysis panel (HMAP) measures separable components of arm motion and simple and complex finger coordination. HMAP testing takes 30 minutes to administer. In separate experiments we have validated the HMAP against the standard grooved pegboard and measures of gait speed, and demonstrated important learning effects over both short durations of days, and longer intervals of months to years in normal subjects of different ages. Stepwise regression demonstrated the strongest co...
Littel, M.; van den Hout, M.A.; Engelhard, I.M.
Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. During this treatment, patients recall traumatic memories while making horizontal eye movements (EM). Studies have shown that EM not only desensitize negative memories but also positive
Farrokhi, Behraz; Erfanian, Abbas
Objective. The primary concern of this study is to develop a probabilistic regression method that would improve the decoding of the hand movement trajectories from epidural ECoG as well as from subdural ECoG signals. Approach. The model is characterized by the conditional expectation of the hand position given the ECoG signals. The conditional expectation of the hand position is then modeled by a linear combination of the conditional probability density functions defined for each segment of the movement. Moreover, a spatial linear filter is proposed for reducing the dimension of the feature space. The spatial linear filter is applied to each frequency band of the ECoG signals and extract the features with highest decoding performance. Main results. For evaluating the proposed method, a dataset including 28 ECoG recordings from four adult Japanese macaques is used. The results show that the proposed decoding method outperforms the results with respect to the state of the art methods using this dataset. The relative kinematic information of each frequency band is also investigated using mutual information and decoding performance. The decoding performance shows that the best performance was obtained for high gamma bands from 50 to 200 Hz as well as high frequency ECoG band from 200 to 400 Hz for subdural recordings. However, the decoding performance was decreased for these frequency bands using epidural recordings. The mutual information shows that, on average, the high gamma band from 50 to 200 Hz and high frequency ECoG band from 200 to 400 Hz contain significantly more information than the average of the rest of the frequency bands ≤ft( pright) for both subdural and epidural recordings. The results of high resolution time-frequency analysis show that ERD/ERS patterns in all frequency bands could reveal the dynamics of the ECoG responses during the movement. The onset and offset of the movement can be clearly identified by the ERD/ERS patterns. Significance
Sun, Xinyao; Byrns, Simon; Cheng, Irene; Zheng, Bin; Basu, Anup
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.
Gabyzon, M Elboim; Engel-Yeger, B; Tresser, S; Springer, S
Virtual reality gaming environments may be used as a supplement to the motor performance assessment tool box by providing clinicians with quantitative information regarding motor performance in terms of movement accuracy and speed, as well as sensory motor integration under different levels of dual tasking. To examine the feasibility of using the virtual reality game `Timocco' as an assessment tool for evaluating goal-directed hand movements among typically developing children. In this pilot study, 47 typically-developing children were divided into two age groups, 4-6 years old and 6-8 years old. Performance was measured using two different virtual environment games (Bubble Bath and Falling Fruit), each with two levels of difficulty. Discriminative validity (age effect) was examined by comparing the performance of the two groups, and by comparing the performance between levels of the games for each group (level effect). Test-retest reliability was examined by reassessing the older children 3-7 days after the first session. The older children performed significantly better in terms of response time, action time, game duration, and efficiency in both games compared to the younger children. Both age groups demonstrated poorer performance at the higher game level in the Bubble Bath game compared to the lower level. A similar level effect was found in the Falling Fruit game for both age groups in response time and efficiency, but not in action time. The performance of the older children was not significantly different between the two sessions at both game levels. The discriminative validity and test-retest reliability indicate the feasibility of using the Timocco virtual reality game as a tool for assessing goal-directed hand movements in children. Further studies should examine its feasibility for use in children with disabilities.
Atzori, Manfredo; Cognolato, Matteo; Müller, Henning
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
Atzori, Manfredo; Cognolato, Matteo; Müller, Henning
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.
Lauritzen, M.; Henriksen, L.; Lassen, N.A.
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-min period at a concentration of 10 mCi/L. The arrival and washout of the radioisotope was recorded during four 1-min periods. Two slices, 2 cm thick, 7 and 12 cm above the orbitomeatal line were obtained in every study. CBF averaged 60 ml/100 g/min (SD +/- 11) in the lower slice and 51 ml/100 g/min (SD +/- 13) in the upper slice. A symmetric pattern comparing right to left sides was found in both slices. Finger tapping and writing with the right hand increased CBF in specific areas of the upper slice: in the contralateral hand area by 35 +/- 15% (p less than 0.025), and in the supplementary motor area on both sides by 34 +/- 15%
Full Text Available The tendency to mimic the behaviour of others is affected by a variety of social factors, and it has been argued that such "mirroring" is often unconsciously deployed as a means of increasing affiliation during interpersonal interactions. However, the relationship between automatic motor imitation and status/power is currently unclear. This paper reports five experiments that investigated whether social status (Experiments 1, 2, and 3 or power (Experiments 4 and 5 had a moderating effect on automatic imitation (AI in finger-movement tasks, using a series of different manipulations. Experiments 1 and 2 manipulated the social status of the observed person using an associative learning task. Experiment 3 manipulated social status via perceived competence at a simple computer game. Experiment 4 manipulated participants' power (relative to the actors in a card-choosing task. Finally, Experiment 5 primed participants using a writing task, to induce the sense of being powerful or powerless. No significant interactions were found between congruency and social status/power in any of the studies. Additionally, Bayesian hypothesis testing indicated that the null hypothesis should be favoured over the experimental hypothesis in all five studies. These findings are discussed in terms of their implications for AI tasks, social effects on mimicry, and the hypothesis of mimicry as a strategic mechanism to promote affiliation.
Brunetti, Riccardo; Del Gatto, Claudia; Cavallina, Clarissa; Farina, Benedetto; Delogu, Franco
The Corsi Block Tapping Task is a widespread test used to assess spatial working memory. Previous research hypothesized that the discrepancy found in some cases between the traditional and the digital (touchscreen) version of the Corsi block tapping task may be due to a direct motor resonance between the experimenter's and the participant's hand movements. However, we hypothesize that this discrepancy might be due to extra movement-related information included in the traditional version, lacking in the digital one. We investigated the effects of such task-irrelevant information using eCorsi, a touchscreen version of the task. In Experiment 1, we manipulate timing in sequence presentation, creating three conditions. In the Congruent condition, the inter-stimulus intervals reflected the physical distance in which the stimuli were spatially placed: The longer the spatial distance, the longer the temporal interval. In the Incongruent condition the timing changed randomly. Finally, in the Isochronous condition every stimulus appeared after a fixed interval, independently from its spatial position. The results showed a performance enhancement in the Congruent condition, suggesting an incidental spatio-temporal binding. In Experiment 2, we added straight lines between each location in the sequences: In the Trajectories condition participants saw trajectories from one spatial position to the other during sequence presentation, while a condition without such trajectories served as control. Results showed better performances in the Trajectories condition. We suggest that the timing and trajectories information play a significant role in the discrepancies found between the traditional and the touchscreen version of the Corsi Block Tapping Task, without the necessity of explanations involving direct motor resonance (e.g. seeing an actual hand moving) as a causal factor.
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.
T. S. Mukhina
Full Text Available Objective: to analyze the characteristics of the functional neuroanatomy of movements in severe traumatic brain injury (STBI patients with varying severity of motor defect versus that in healthy individuals for the study of brain neuroplasticity as a basis of compensation.Patients and methods. Functional magnetic resonance imaging (fMRI, 3T was used to analyze cerebral hemodynamic changes in 28 patients with STBI during an active right-hand finger tapping task. A control group consisted of 17 healthy individuals. The percentage of representation of individual brain structures involved in movements and volume activation (Vox was determined in fMRI responses.Results. The patient group showed a tendency for an increased fMRI response diffusion with the emergence of activation zones (the left frontal and parietal regions, as well as the occiptal and temporal regions of the cerebral hemispheres that are atypical for healthy individuals during motor exercises. This trend is more evident in patients with right-sided hemiparesis.Conclusion. The results of the study clarify the existing ideas about the neurophysiological mechanisms of motor impairment and compensation in traumatic brain injury, which is important for the development and improvement of neurorehabilitation techniques. There is evidence for the hypothesis that the extrapyramidal system may be actively involved in the compensation for post-traumatic musculoskeletal defect, which was earlier proposed by E.V. Sharova et al. (2014.
Full Text Available OBJETIVOS: Assim como a imagética motora, o reconhecimento de partes do corpo aciona representações somatosensoriais específicas. Essas representações são ativadas implicitamente para comparar o corpo com o estímulo. No presente estudo, investigou-se a influência da informação proprioceptiva da postura no reconhecimento de partes do corpo (mãos e propõe-se a utilização dessa tarefa na reabilitação de pacientes neurológicos. MATERIAIS E MÉTODOS: Dez voluntários destros participaram do experimento. A tarefa era reconhecer a lateralidade de figuras da mão apresentada, em várias perspectivas e em vários ângulos de orientação. Para a figura da mão direita, o voluntário pressionava a tecla direita e para a figura da mão esquerda, a tecla esquerda. Os voluntários realizavam duas sessões: uma com as mãos na postura prona e outra com as mãos na postura supina. RESULTADOS: Os tempos de reação manual (TRM eram maiores para as vistas e orientações, nas quais é difícil realizar o movimento real, mostrando que durante a tarefa, existe um acionamento de representações motoras para comparar o corpo com o estímulo. Além disso, existe uma influência da postura do sujeito em vistas e ângulos específicos. CONCLUSÕES: Estes resultados mostram que representações motoras são ativadas para comparar o corpo com o estímulo e que a postura da mão influencia esta ressonância entre estímulo e parte do corpo.OBJECTIVE: Recognition of body parts activates specific somatosensory representations in a way that is similar to motor imagery. These representations are implicitly activated to compare the body with the stimulus. In the present study, we investigate the influence of proprioceptive information relating to body posture on the recognition of body parts (hands. It proposes that this task could be used for rehabilitation of neurological patients. METHODS: Ten right-handed volunteers participated in this experiment. The
Tamaru, Yoshiki; Naito, Yasuo; Nishikawa, Takashi
Elderly people are less able to manipulate objects skilfully than young adults. Although previous studies have examined age-related deterioration of hand movements with a focus on the phase after grasping objects, the changes in the reaching phase have not been studied thus far. We aimed to examine whether changes in hand shape patterns during the reaching phase of grasping movements differ between young adults and the elderly. Ten healthy elderly adults and 10 healthy young adults were examined using the Simple Test for Evaluating Hand Functions and kinetic analysis of hand pre-shaping reach-to-grasp tasks. The results were then compared between the two groups. For kinetic analysis, we measured the time of peak tangential velocity of the wrist and the inter-fingertip distance (the distance between the tips of the thumb and index finger) at different time points. The results showed that the elderly group's performance on the Simple Test for Evaluating Hand Functions was significantly lower than that of the young adult group, irrespective of whether the dominant or non-dominant hand was used, indicating deterioration of hand movement in the elderly. The peak tangential velocity of the wrist in either hand appeared significantly earlier in the elderly group than in the young adult group. The elderly group also showed larger inter-fingertip distances with arch-like fingertip trajectories compared to the young adult group for all object sizes. To perform accurate prehension, elderly people have an earlier peak tangential velocity point than young adults. This allows for a longer adjustment time for reaching and grasping movements and for reducing errors in object prehension by opening the hand and fingers wider. Elderly individuals gradually modify their strategy based on previous successes and failures during daily living to compensate for their decline in dexterity and operational capabilities. © 2017 Japanese Psychogeriatric Society.
Kearns, M.; Engelhard, I.M.
A principle characteristic of public speaking anxiety relates to intrusive mental images of potential future disasters. Previous research has found that the self-reported emotionality of such “flashforwards” can be reduced by a cognitively demanding, dual-task (e.g., making eye movements) performed
Full Text Available Mental rotation of visual images of body parts and abstract shapes can be influenced by simultaneous motor activity. Children in particular seem to have a strong coupling between motor and cognitive processes. We investigated the influence of a rotational hand movement performed by rotating a knob on mental rotation performance in primary school-age children (N= 83; Age range: 7.0-8.3 and 9.0-10.11 years. In addition, we assessed the role of motor ability in this relationship. Boys in the 7-8-year-old group were faster when mentally and manually rotating in the same direction than in the opposite direction. For girls and older children this effect was not found. A positive relationship was found between motor ability and accuracy on the mental rotation task: stronger motor ability related to improved mental rotation performance. In both age groups, children with more advanced motor abilities were more likely to adopt motor processes to solve mental rotation tasks if the mental rotation task was primed by a motor task. Our evidence supports the idea that an overlap between motor and visual cognitive processes in children is influenced by motor ability.
Gallivan, Jason P; McLean, D Adam; Flanagan, J Randall; Culham, Jody C
Planning object-directed hand actions requires successful integration of the movement goal with the acting limb. Exactly where and how this sensorimotor integration occurs in the brain has been studied extensively with neurophysiological recordings in nonhuman primates, yet to date, because of limitations of non-invasive methodologies, the ability to examine the same types of planning-related signals in humans has been challenging. Here we show, using a multivoxel pattern analysis of functional MRI (fMRI) data, that the preparatory activity patterns in several frontoparietal brain regions can be used to predict both the limb used and hand action performed in an upcoming movement. Participants performed an event-related delayed movement task whereby they planned and executed grasp or reach actions with either their left or right hand toward a single target object. We found that, although the majority of frontoparietal areas represented hand actions (grasping vs reaching) for the contralateral limb, several areas additionally coded hand actions for the ipsilateral limb. Notable among these were subregions within the posterior parietal cortex (PPC), dorsal premotor cortex (PMd), ventral premotor cortex, dorsolateral prefrontal cortex, presupplementary motor area, and motor cortex, a region more traditionally implicated in contralateral movement generation. Additional analyses suggest that hand actions are represented independently of the intended limb in PPC and PMd. In addition to providing a unique mapping of limb-specific and action-dependent intention-related signals across the human cortical motor system, these findings uncover a much stronger representation of the ipsilateral limb than expected from previous fMRI findings.
Musicians use different kinds of imagery. This review focuses on kinesthetic imagery, which has been shown to be an effective complement to actively playing an instrument. However, experience in actual movement performance seems to be a requirement for a recruitment of those brain areas representing movement ideation during imagery. An internal model of movement performance might be more differentiated when training has been more intense or simply performed more often. Therefore, with respect to kinesthetic imagery, these strategies are predominantly found in professional musicians. There are a few possible reasons as to why kinesthetic imagery is used in addition to active training; one example is the need for mental rehearsal of the technically most difficult passages. Another reason for mental practice is that mental rehearsal of the piece helps to improve performance if the instrument is not available for actual training as is the case for professional musicians when they are traveling to various appearances. Overall, mental imagery in musicians is not necessarily specific to motor, somatosensory, auditory, or visual aspects of imagery, but integrates them all. In particular, the audiomotor loop is highly important, since auditory aspects are crucial for guiding motor performance. All these aspects result in a distinctive representation map for the mental imagery of musical performance. This review summarizes behavioral data, and findings from functional brain imaging studies of mental imagery of musical performance.
Shibata, E; Kaneko, F
The perceptual integration of afferent inputs from two antagonistic muscles, or the perceptual integration of afferent input and motor imagery are related to the generation of a kinesthetic sensation. However, it has not been clarified how, or indeed whether, a kinesthetic perception would be generated by motor imagery if afferent inputs from two antagonistic muscles were simultaneously induced by tendon vibration. The purpose of this study was to investigate how a kinesthetic perception would be generated by motor imagery during co-vibration of the two antagonistic muscles at the same frequency. Healthy subjects participated in this experiment. Illusory movement was evoked by tendon vibration. Next, the subjects imaged wrist flexion movement simultaneously with tendon vibration. Wrist flexor and extensor muscles were vibrated according to 4 patterns such that the difference between the two vibration frequencies was zero. After each trial, the perceived movement sensations were quantified on the basis of the velocity and direction of the ipsilateral hand-tracking movements. When the difference in frequency applied to the wrist flexor and the extensor was 0Hz, no subjects perceived movements without motor imagery. However, during motor imagery, the flexion velocity of the perceived movement was higher than the flexion velocity without motor imagery. This study clarified that the afferent inputs from the muscle spindle interact with motor imagery, to evoke a kinesthetic perception, even when the difference in frequency applied to the wrist flexor and extensor was 0Hz. Furthermore, the kinesthetic perception resulting from integrations of vibration and motor imagery increased depending on the vibration frequency to the two antagonistic muscles. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Wilhelm, Emmanuelle; Quoilin, Caroline; Petitjean, Charlotte; Duque, Julie
Background: Many previous transcranial magnetic stimulation (TMS) studies have investigated corticospinal excitability changes occurring when choosing which hand to use for an action, one of the most frequent decision people make in daily life. So far, these studies have applied single-pulse TMS eliciting motor-evoked potential (MEP) in one hand when this hand is either selected or non-selected. Using such method, hand choices were shown to entail the operation of two inhibitory mechanisms, suppressing MEPs in the targeted hand either when it is non-selected (competition resolution, CR) or selected (impulse control, IC). However, an important limitation of this “Single-Coil” method is that MEPs are elicited in selected and non-selected conditions during separate trials and thus those two settings may not be completely comparable. Moreover, a more important problem is that MEPs are computed in relation to the movement of different hands. The goal of the present study was to test a “Double-Coil” method to evaluate IC and CR preceding the same hand responses by applying Double-Coil TMS over the two primary motor cortices (M1) at a near-simultaneous time (1 ms inter-pulse interval). Methods: MEPs were obtained in the left (MEPLEFT) and right (MEPRIGHT) hands while subjects chose between left and right hand key-presses in blocks using a Single-Coil or a Double-Coil method; in the latter blocks, TMS was either applied over left M1 first (TMSLRM1 group, n = 12) or right M1 first (TMSRLM1 group, n = 12). Results: MEPLEFT were suppressed preceding both left (IC) and right (CR) hand responses whereas MEPRIGHT were only suppressed preceding left (CR) but not right (IC) hand responses. This result was observed regardless of whether Single-Coil or Double-Coil TMS was applied in the two subject groups. However, in the TMSLRM1 group, the MEP suppression was attenuated in Double-Coil compared to Single-Coil blocks for both IC and CR, when probed with MEPLEFT (elicited by
Balslev, Daniela; Cole, Jonathan; Miall, R Chris
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...
Full Text Available Musicians use different kinds of imagery. This review focuses on kinesthetic imagery, which has been shown to be an effective complement to actively playing an instrument. However, experience in actual movement performance seems to be a requirement for a recruitment of those brain areas representing movement ideation during imagery. An internal model of movement performance might be more differentiated when training has been more intense or simply performed more often. Therefore, with respect to kinesthetic imagery, these strategies are predominantly found in professional musicians. There are a few possible reasons as to why kinesthetic imagery is used in addition to active training; one example is the need for mental rehearsal of the technically most difficult passages. Training difficult passages repeatedly has the potential to induce fatigue in tendons and muscles and can ultimately result in the development of dystonia. Another reason for mental practice is that mental rehearsal of the piece helps to improve performance if the instrument is not available for actual training as is the case for professional musicians when they are travelling to various appearances. Overall, mental imagery in musicians is not necessarily specific to motor, somatosensory, auditory or visual aspects of imagery, but integrates them all. In particular, the audiomotor loop is highly important, since auditory aspects are crucial for guiding motor performance. Furthermore, slight co-movement, for instance of the fingers, usually occurs when imagining musical performance, a situation different to the laboratory condition where movement execution is strictly controlled. All these aspects result in a distinctive representation map for the mental imagery of musical performance. This review summarizes behavioral data, and findings from functional brain imaging studies of mental imagery of musical performance.
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…
Bardolph, Megan; Coulson, Seana
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. PMID:25566041
Kemper, K.; Throop, H.
One of the greatest impacts on the global carbon cycle is changes in land use. Making this concept relevant and inquiry-based for high school students is challenging. Many are familiar with reconstructing paleo-climate from ice core data, but few have a connection to current climate research. Many students ask questions like 'What will our area be like in 20 years?' or 'How much does planting trees help?' while few have the scientific language to engage in a discussion to answer these questions. Our work connects students to climate change research in several ways: first, teacher Keska Kemper engaged in field research with Dr. Heather Throop creating a 'teacher in the field' perspective for students in the classroom. Dr. Throop met with Keska Kemper's students several times to develop an inquiry-based field study. Students predicted and then measured rates of respiration between different soil types in an urban park close to their school. Students then could compare their results from Portland, Oregon to Throop's work across a rain gradient in Australia. Discussions about percent tree cover and soil carbon helped students see connections between land use changes and changes in carbon cycling. Last, students examined satellite imagery to determine percent tree cover and numberss of trees to compare to soil carbon in the same region. Students were able to examine imagery over the last 30 years to visualize land use changes in the greater Portland area.
are significantly associated with age in cohorts of typical and at-risk infantsdiffer significantly at 5–6 months of age, depending on the context: relating either with an object or a person.Environmental and developmental factors shape the developmental trajectories of hand movements in different cohorts: environment for infants with VIMs; stage of development for premature infants and those with West syndrome; and both factors for infants with orality disorders.The curvature of hand movements specifically reflects atypical development in infants with West syndrome when developmental age is considered.We aimed to discriminate between typical and atypical developmental trajectory patterns of at-risk infants in an interactive setting in this observational and longitudinal study, with the assumption that hand movements (HM reflect preverbal communication and its disorders. We examined the developmental trajectories of HM in five cohorts of at-risk infants and one control cohort, followed from ages 2 to 10 months: 25 West syndrome (WS, 13 preterm birth (PB, 16 orality disorder (OD, 14 with visually impaired mothers (VIM, 7 early hospitalization (EH, and 19 typically developing infants (TD. Video-recorded data were collected in three different structured interactive contexts. Descriptors of the hand motion were used to examine the extent to which HM were associated with age and cohort. We obtained four principal results: (i the kinematics of HM (spatial use, curvature, acceleration, and velocity were significantly associated with age in all cohorts; (ii HM significantly differed at 5–6 months of age in TD infants, depending on the context; (iii environmental and developmental factors shaped the developmental trajectories of HM in different cohorts: environment for VIM, development for PB and WS, and both factors for OD and; (iv the curvatures of HM showed atypical development in WS infants when developmental age was considered. These findings support the importance
LeMoyne, Robert; Mastroianni, Timothy
Smartphones and portable media devices are both equipped with sensor components, such as accelerometers. A software application enables these devices to function as a robust wireless accelerometer platform. The recorded accelerometer waveform can be transmitted wireless as an e-mail attachment through connectivity to the Internet. The implication of such devices as a wireless accelerometer platform is the experimental and post-processing locations can be placed anywhere in the world. Gait was quantified by mounting a smartphone or portable media device proximal to the lateral malleolus of the ankle joint. Attributes of the gait cycle were quantified with a considerable accuracy and reliability. The patellar tendon reflex response was quantified by using the device in tandem with a potential energy impact pendulum to evoke the patellar tendon reflex. The acceleration waveform maximum acceleration feature of the reflex response displayed considerable accuracy and reliability. By mounting the smartphone or portable media device to the dorsum of the hand through a glove, Parkinson's disease hand tremor was quantified and contrasted with significance to a non-Parkinson's disease steady hand control. With the methods advocated in this chapter, any aspect of human movement may be quantified through smartphones or portable media devices and post-processed anywhere in the world. These wearable devices are anticipated to substantially impact the biomedical and healthcare industry.
Grangeon, Murielle; Guillot, Aymeric; Sancho, Pierre-Olivier; Picot, Marion; Revol, Patrice; Rode, Gilles; Collet, Christian
To test the effect of a postsurgical motor imagery program in the rehabilitation of a patient with quadriplegia. Crossover design with kinematic analysis. Rehabilitation Hospital of Lyon. Study approved by the local Human Research Ethics Committee. C6-level injured patient (American Spinal Injury Association Impairment Scale grade A) with no voluntary elbow extension (triceps brachialis score 1). The surgical procedure was to transfer the distal insertion of the biceps brachii onto the triceps tendon of both arms. The postsurgical intervention on the left arm included 10 sessions of physical rehabilitation followed by 10 motor imagery sessions of 30 minutes each. The patient underwent 5 sessions a week during 2 consecutive weeks. The motor imagery content included mental representations based on elbow extension involved in goal-directed movements. The rehabilitation period of the right arm was reversed, with motor imagery performed first, followed by physical therapy. The kinematics of upper-limb movements was recorded (movement time and variability) before and after each type of rehabilitation period. A long-term retention test was performed 1 month later. Motor imagery training enhanced motor recovery by reducing hand trajectory variability-that is, improving smoothness. Motor performance then remained stable over 1 month. Motor imagery improved motor recovery when associated with physical therapy, with motor performance remaining stable over the 1-month period. We concluded that motor imagery should be successfully associated with classic rehabilitation procedure after tendon transfer. Physical sessions may thus be shortened if too stressful or painful. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Federal Laboratory Consortium — The Imagery Data Base Facility supports AFRL and other government organizations by providing imagery interpretation and analysis to users for data selection, imagery...
Renata C. M. Lima
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.
Full Text Available Feedback design is an important issue in motor imagery BCI systems. Regardless, to date it has not been reported how feedback presentation can optimize co-adaptation between a human brain and such systems. This paper assesses the effect of realistic visual feedback on users’ BC performance and motor imagery skills. We previously developed a tele-operation system for a pair of humanlike robotic hands and showed that BCI control of such hands along with first-person perspective visual feedback of movements can arouse a sense of embodiment in the operators. In the first stage of this study, we found that the intensity of this ownership illusion was associated with feedback presentation and subjects’ performance during BCI motion control. In the second stage, we probed the effect of positive and negative feedback bias on subjects’ BCI performance and motor imagery skills. Although the subject specific classifier, which was set up at the beginning of experiment, detected no significant change in the subjects’ online performance, evaluation of brain activity patterns revealed that subjects’ self-regulation of motor imagery features improved due to a positive bias of feedback and a possible occurrence of ownership illusion. Our findings suggest that in general training protocols for BCIs, manipulation of feedback can play an important role in the optimization of subjects’ motor imagery skills.
Reinkensmeyer, David J; Wolbrecht, Eric T; Chan, Vicky; Chou, Cathy; Cramer, Steven C; Bobrow, James E
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.
Miller, W. F.; Whisler, F. D.; Robinette, H. R.; Finnie, D.; Cannon, T.
A cost-effective aerial surveillance technique is proposed for detection and identification of suspended solids which would be operational for both governmental monitoring organizations and private individuals operating catfish farms. Sixteen catfish ponds were flown daily for seven days using two hand-held 35 mm cameras with both Kodachrome X and Ektachrome infrared film. Hue, value, and chroma designations were recorded for each pond on each date by three interpreters, and the accepted color was that recorded by at least two of the interpreters, or if there was a three hue range, the median was accepted. Relations between suspended solids and color designations were analyzed graphically, and chroma was discarded due to an apparent lack of correlation. The data obtained were then analyzed by multiple regression. Significant correlations were revealed between hue and value and total and inorganic suspended solids. If perfected, this technique could be developed to sufficent accuracy for large-scale reconnaissance surveys to monitor the quality of rivers and streams.
Karaçizmeli, Cengiz; Çakır, Gökçe; Tükel, Dilek
In this work, the mechatronic based robotic hand is controlled by the position data taken from the glove which has flex sensors mounted to capture finger bending of the human hand. The angular movement of human hand’s fingers are perceived and processed by a microcontroller, and the robotic hand is controlled by actuating servo motors. It has seen that robotic hand can simulate the movement of the human hand that put on the glove, during tests have done. This robotic hand can be used not only...
Gatti, R; Tettamanti, A; Gough, P M; Riboldi, E; Marinoni, L; Buccino, G
Both motor imagery and action observation have been shown to play a role in learning or re-learning complex motor tasks. According to a well accepted view they share a common neurophysiological basis in the mirror neuron system. Neurons within this system discharge when individuals perform a specific action and when they look at another individual performing the same or a motorically related action. In the present paper, after a short review of literature on the role of action observation and motor imagery in motor learning, we report the results of a kinematics study where we directly compared motor imagery and action observation in learning a novel complex motor task. This involved movement of the right hand and foot in the same angular direction (in-phase movement), while at the same time moving the left hand and foot in an opposite angular direction (anti-phase movement), all at a frequency of 1Hz. Motor learning was assessed through kinematics recording of wrists and ankles. The results showed that action observation is better than motor imagery as a strategy for learning a novel complex motor task, at least in the fast early phase of motor learning. We forward that these results may have important implications in educational activities, sport training and neurorehabilitation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
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.
Efeito das terapias associadas de imagem motora e de movimento induzido por restrição na hemiparesia crônica: estudo de caso Effects of associated therapies of motor imagery and constraint-induced movement in chronic hemiparesis: a case study
Claudia Morais Trevisan
Full Text Available Este estudo analisa os efeitos da associação das terapias de imagem motora e de movimento induzido por restrição na reeducação funcional do membro superior (MS de um paciente com deficit sensorial e motor determinado por acidente vascular encefálico (AVE. A terapia de imagem motora (IM consistiu em: 1o, estimulo visual do espelho, em 3 sessões semanais de 30 a 60 minutos por 4 semanas; e 2o, IM com prática mental, em 3 sessões semanais de 15 minutos por 3 semanas. Por último foi aplicada a terapia de indução ao movimento por restrição do membro superior não-afetado por 14 dias, em 10 dos quais foi feita atividade funcional do membro parético por 6 horas diárias. Além da avaliação clinica da sensibilidade e medida da força de preensão palmar, antes do tratamento e após cada modalidade de terapia foi medida a amplitude de movimentos de ombro, cotovelo e punho e aplicada a escala de avaliação motora (EAM. Os escores dos quatro momentos da coleta foram comparados estatisticamente. Após o tratamento os resultados mostraram diferença significativa (pThis study assessed the efficacy of the association of motor imagery and constraint-induced movement therapies in functional rehabilitation of the upper limb in a patient with somatosensory and motor deficits following stroke. Motor imagery (MI therapy, i.e., mental simulation of body image, consisted in: 1st, mirror visual stimulus, at three 30-60-minute weekly sessions for four weeks; and 2nd, MI with mental practice, at three 15-minute sessions per week for three weeks. Lastly, constraint-induced movement therapy was applied for 14 days, in 10 of which the patient underwent 6 hours daily of paretic limb functional training. The patient was assessed at baseline and at the end of each therapy modality as to clinical examination of sensation; hand grip strength; shoulder, elbow and wrist range of motion; and the motor assessment scale (MAS was applied. Scores obtained at the
Rodrigues, E C; Lemos, T; Gouvea, B; Volchan, E; Imbiriba, L A; Vargas, C D
The aim of this study was to investigate the effect of imagining an action implicating the body axis in the kinesthetic and visual motor imagery modalities upon the balance control system. Body sway analysis (measurement of center of pressure, CoP) together with electromyography (EMG) recording and verbal evaluation of imagery abilities were obtained from subjects during four tasks, performed in the upright position: to execute bilateral plantar flexions; to imagine themselves executing bilateral plantar flexions (kinesthetic modality); to imagine someone else executing the same movement (visual modality), and to imagine themselves singing a song (as a control imagery task). Body sway analysis revealed that kinesthetic imagery leads to a general increase in CoP oscillation, as reflected by an enhanced area of displacement. This effect was also verified for the CoP standard deviation in the medial-lateral direction. An increase in the trembling displacement (equivalent to center of pressure minus center of gravity) restricted to the anterior-posterior direction was also observed to occur during kinesthetic imagery. The visual imagery task did not differ from the control (sing) task for any of the analyzed parameters. No difference in the subjects' ability to perform the imagery tasks was found. No modulation of EMG data were observed across imagery tasks, indicating that there was no actual execution during motor imagination. These results suggest that motor imagery performed in the kinesthetic modality evokes motor representations involved in balance control. Copyright (c)10 IBRO. Published by Elsevier Ltd. All rights reserved.
Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi
Brain computer interfaces (BCIs) have been developed and implemented in many areas as a new communication channel between the human brain and external devices. Despite their rapid growth and broad popularity, the inaccurate performance and cost of user-training are yet the main issues that prevent their application out of the research and clinical environment. We previously introduced a BCI system for the control of a very humanlike android that could raise a sense of embodiment and agency in the operators only by imagining a movement (motor imagery) and watching the robot perform it. Also using the same setup, we further discovered that the positive bias of subjects' performance both increased their sensation of embodiment and improved their motor imagery skills in a short period. In this work, we studied the shared mechanism between the experience of embodiment and motor imagery. We compared the trend of motor imagery learning when two groups of subjects BCI-operated different looking robots, a very humanlike android's hands and a pair of metallic gripper. Although our experiments did not show a significant change of learning between the two groups immediately during one session, the android group revealed better motor imagery skills in the follow up session when both groups repeated the task using the non-humanlike gripper. This result shows that motor imagery skills learnt during the BCI-operation of humanlike hands are more robust to time and visual feedback changes. We discuss the role of embodiment and mirror neuron system in such outcome and propose the application of androids for efficient BCI training.
Full Text Available Brain computer interfaces (BCIs have been developed and implemented in many areas as a new communication channel between the human brain and external devices. Despite their rapid growth and broad popularity, the inaccurate performance and cost of user-training are yet the main issues that prevent their application out of the research and clinical environment. We previously introduced a BCI system for the control of a very humanlike android that could raise a sense of embodiment and agency in the operators only by imagining a movement (motor imagery and watching the robot perform it. Also using the same setup, we further discovered that the positive bias of subjects' performance both increased their sensation of embodiment and improved their motor imagery skills in a short period. In this work, we studied the shared mechanism between the experience of embodiment and motor imagery. We compared the trend of motor imagery learning when two groups of subjects BCI-operated different looking robots, a very humanlike android's hands and a pair of metallic gripper. Although our experiments did not show a significant change of learning between the two groups immediately during one session, the android group revealed better motor imagery skills in the follow up session when both groups repeated the task using the non-humanlike gripper. This result shows that motor imagery skills learnt during the BCI-operation of humanlike hands are more robust to time and visual feedback changes. We discuss the role of embodiment and mirror neuron system in such outcome and propose the application of androids for efficient BCI training.
Eisenmann, Jonathan; Parent, Rick
In this paper we present experiments and results pertaining to the perception of depth in stereoscopic viewing of synthetic imagery. In computer animation, typical synthetic imagery is highly textured and uses stylized illumination of abstracted material models by abstracted light source models. While there have been numerous studies concerning stereoscopic capabilities, conventions for staging and cinematography in stereoscopic movies have not yet been well-established. Our long-term goal is to measure the effectiveness of various cinematography techniques on the human visual system in a theatrical viewing environment. We would like to identify the elements of stereoscopic cinema that are important in terms of enhancing the viewer's understanding of a scene as well as providing guidelines for the cinematographer relating to storytelling. In these experiments we isolated stereoscopic effects by eliminating as many other visual cues as is reasonable. In particular, we aim to empirically determine what types of movement in synthetic imagery affect the perceptual depth sensing capabilities of our viewers. Using synthetic imagery, we created several viewing scenarios in which the viewer is asked to locate a target object's depth in a simple environment. The scenarios were specifically designed to compare the effectiveness of stereo viewing, camera movement, and object motion in aiding depth perception. Data were collected showing the error between the choice of the user and the actual depth value, and patterns were identified that relate the test variables to the viewer's perceptual depth accuracy in our theatrical viewing environment.
Greve, L; Pfau, T; Dyson, S
Equine movement symmetry is changed when turning, which may induce alterations in thoracolumbosacral kinematics; however, this has not previously been investigated. Our objectives were to document thoracolumbar movement in subjectively sound horses comparing straight lines with circles on both reins and to relate these observations to the objectively determined symmetry/asymmetry of hindlimb gait. Fourteen non-lame horses were assessed prospectively in a non-random, cross-sectional survey. The horses were trotted in straight lines and lunged on both reins and inertial sensor data collected at landmarks: withers, T13 and T18, L3, tubera sacrale, and left and right tubera coxae. Data were processed using published methods; angular motion range of motion (ROM; flexion-extension, axial rotation, lateral bending) and translational ROM (dorsoventral and lateral) and symmetry within each stride were assessed. The dorsoventral movement of the back exhibited a sinusoidal pattern with two oscillations per stride. Circles induced greater asymmetry in dorsoventral movement within each stride (mean ± standard deviation, up to 9 ± 6%) compared with straight lines (up to 6 ± 6%). The greatest amplitude of dorsoventral movement (119 ± 14 mm in straight lines vs. 126 ± 20 mm in circles) occurred at T13. Circles induced greater flexion-extension ROM (>1.3°; P = 0.002), lateral bending (>16°; P 16 mm; P = 0.002) compared with straight lines. Circles induced a movement pattern similar to an inside hindlimb lameness, which was significantly associated with the circle-induced greater asymmetry of dorsoventral movement of the thoracolumbar region (P = 0.03). Moving in a circle induces measurable changes in thoracolumbar movement compared with moving in straight lines, associated with alterations in the hindlimb gait. Copyright © 2017 Elsevier Ltd. All rights reserved.
Toppi, J.; Risetti, M.; Quitadamo, L. R.; Petti, M.; Bianchi, L.; Salinari, S.; Babiloni, F.; Cincotti, F.; Mattia, D.; Astolfi, L.
Objective. It is well known that to acquire sensorimotor (SMR)-based brain-computer interface (BCI) control requires a training period before users can achieve their best possible performances. Nevertheless, the effect of this training procedure on the cortical activity related to the mental imagery ability still requires investigation to be fully elucidated. The aim of this study was to gain insights into the effects of SMR-based BCI training on the cortical spectral activity associated with the performance of different mental imagery tasks. Approach. Linear cortical estimation and statistical brain mapping techniques were applied on high-density EEG data acquired from 18 healthy participants performing three different mental imagery tasks. Subjects were divided in two groups, one of BCI trained subjects, according to their previous exposure (at least six months before this study) to motor imagery-based BCI training, and one of subjects who were naive to any BCI paradigms. Main results. Cortical activation maps obtained for trained and naive subjects indicated different spectral and spatial activity patterns in response to the mental imagery tasks. Long-term effects of the previous SMR-based BCI training were observed on the motor cortical spectral activity specific to the BCI trained motor imagery task (simple hand movements) and partially generalized to more complex motor imagery task (playing tennis). Differently, mental imagery with spatial attention and memory content could elicit recognizable cortical spectral activity even in subjects completely naive to (BCI) training. Significance. The present findings contribute to our understanding of BCI technology usage and might be of relevance in those clinical conditions when training to master a BCI application is challenging or even not possible.
Cabral-Sequeira, Audrey Sartori; Coelho, Daniel Boari; Teixeira, Luis Augusto
This experiment was designed to evaluate the effects of pure motor imagery training (MIT) and its combination with physical practice on learning an aiming task with the more affected arm in adolescents suffering from cerebral palsy. Effect of MIT was evaluated as a function of side of hemiparesis. The experiment was accomplished by 11- to 16-year-old participants (M = 13.58 years), who suffered left (n = 16) or right (n = 15) mild hemiparesis. They were exposed to pure MIT (day 1) followed by physical practice (day 2) on an aiming task demanding movement accuracy and speed. Posttraining movement kinematics of the group receiving MIT were compared with movement kinematics of the control group after receiving recreational activities (day 1) and physical practice (day 2). Kinematic analysis showed that MIT led to decreased movement time and straighter hand displacements to the target. Performance achievements from MIT were increased with further physical practice, leading to enhanced effects on motor learning. Retention evaluation indicated that performance improvement from pure MIT and its combination with physical practice were stable over time. Performance achievements were equivalent between adolescents with either right or left hemiparesis, suggesting similar capacity between these groups to achieve performance improvement from pure imagery training and from its association with physical practice. Our results suggest that motor imagery training is a procedure potentially useful to increase motor learning achievements in individuals suffering from cerebral palsy.
Peters, Chris; Allan, Stuart
the gradual disappearance of media from personal consciousness in a digital age. If ceaselessness is a defining characteristic of the current era, our analysis reveals that the use of smartphone cameras is indicative of people affectively and self-consciously deploying the technology to try to arrest......User-based research into the lived experiences associated with smartphone camera practices – in particular, the taking, storing, curating, and sharing of personal imagery in the digital media sphere – remains scarce, especially in contrast to their increasing ubiquity. Accordingly, this article...... social bonds, and encompass a future-oriented perspective. Relatedly, in terms of photographic composition, visual content tends to circulate around the social presence of others, boundedness of event, perceived aesthetic value, and intended shareability. Our findings question certain formulations about...
Full Text Available EEG-based discrimination between different motor imagery states has been subject of a number of studies in healthy subjects. We investigated the EEG of 15 patients with complete spinal cord injury during imagined right hand, left hand, and feet movements. In detail we studied pair-wise discrimination functions between the 3 types of motor imagery. The following classification accuracies (mean ± SD were obtained: left versus right hand 65.03% ± 8.52, left hand versus feet 68.19% ± 11.08, and right hand versus feet 65.05% ± 9.25. In 5 out of 8 paralegic patients, the discrimination accuracy was greater than 70% but in only 1 out of 7 tetraplagic patients. The present findings provide evidence that in the majority of paraplegic patients an EEG-based BCI could achieve satisfied results. In tetraplegic patients, however, it is expected that extensive training-sessions are necessary to achieve a good BCI performance at least in some subjects.
Rameckers, E.A.A.; Speth, L.A.; Duysens, J.E.J.; Vles, J.S.; Smits-Engelsman, B.C.M.
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
Iftime-Nielsen, Simona Denisia; Christensen, Mark Schram; Vingborg, Rune Jersin
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...
Full Text Available Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS for developing Brain-Computer Interface (BCI by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM, so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity.
Anil Ufuk Batmaz
Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions 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.
Wong, Sarah Shi Hui; Lim, Stephen Wee Hun
We empirically investigated the effect of mental imagery on young children's music compositional creativity. Children aged 5 to 8 years participated in two music composition sessions. In the control session, participants based their composition on a motif that they had created using a sequence of letter names. In the mental imagery session, participants were given a picture of an animal and instructed to imagine the animal's sounds and movements, before incorporating what they had imagined into their composition. Six expert judges independently rated all music compositions on creativity based on subjective criteria (consensual assessment). Reliability analyses indicated that the expert judges demonstrated a high level of agreement in their ratings. The mental imagery compositions received significantly higher creativity ratings by the expert judges than did the control compositions. These results provide evidence for the effectiveness of mental imagery in enhancing young children's music compositional creativity.
Lim, Stephen Wee Hun
We empirically investigated the effect of mental imagery on young children’s music compositional creativity. Children aged 5 to 8 years participated in two music composition sessions. In the control session, participants based their composition on a motif that they had created using a sequence of letter names. In the mental imagery session, participants were given a picture of an animal and instructed to imagine the animal’s sounds and movements, before incorporating what they had imagined into their composition. Six expert judges independently rated all music compositions on creativity based on subjective criteria (consensual assessment). Reliability analyses indicated that the expert judges demonstrated a high level of agreement in their ratings. The mental imagery compositions received significantly higher creativity ratings by the expert judges than did the control compositions. These results provide evidence for the effectiveness of mental imagery in enhancing young children’s music compositional creativity. PMID:28296965
Trojan, Jörg; Diers, Martin; Fuchs, Xaver; Bach, Felix; Bekrater-Bodmann, Robin; Foell, Jens; Kamping, Sandra; Rance, Mariela; Maaß, Heiko; Flor, Herta
Mirror training and movement imagery have been demonstrated to be effective in treating several clinical conditions, such as phantom limb pain, stroke-induced hemiparesis, and complex regional pain syndrome. This article presents an augmented reality home-training system based on the mirror and imagery treatment approaches for hand training. A head-mounted display equipped with cameras captures one hand held in front of the body, mirrors this hand, and displays it in real time in a set of four different training tasks: (1) flexing fingers in a predefined sequence, (2) moving the hand into a posture fitting into a silhouette template, (3) driving a "Snake" video game with the index finger, and (4) grasping and moving a virtual ball. The system records task performance and transfers these data to a central server via the Internet, allowing monitoring of training progress. We evaluated the system by having 7 healthy participants train with it over the course of ten sessions of 15-min duration. No technical problems emerged during this time. Performance indicators showed that the system achieves a good balance between relatively easy and more challenging tasks and that participants improved significantly over the training sessions. This suggests that the system is well suited to maintain motivation in patients, especially when it is used for a prolonged period of time.
Kondo, Toshiyuki; Saeki, Midori; Hayashi, Yoshikatsu; Nakayashiki, Kosei; Takata, Yohei
Event-related desynchronization (ERD) of the electroencephalogram (EEG) from the motor cortex is associated with execution, observation, and mental imagery of motor tasks. Generation of ERD by motor imagery (MI) has been widely used for brain-computer interfaces (BCIs) linked to neuroprosthetics and other motor assistance devices. Control of MI-based BCIs can be acquired by neurofeedback training to reliably induce MI-associated ERD. To develop more effective training conditions, we investigated the effect of static and dynamic visual representations of target movements (a picture of forearms or a video clip of hand grasping movements) during the BCI neurofeedback training. After 4 consecutive training days, the group that performed MI while viewing the video showed significant improvement in generating MI-associated ERD compared with the group that viewed the static image. This result suggests that passively observing the target movement during MI would improve the associated mental imagery and enhance MI-based BCIs skills. Copyright © 2014 Elsevier B.V. All rights reserved.
Full Text Available Abstract Background Synchrony of coupled oscillations of ipsilateral hand and foot may be achieved by controlling the interlimb phase difference through a crossed kinaesthetic feedback between the two limbs, or by an independent linkage of each limb cycle to a common clock signal. These alternative models may be experimentally challenged by comparing the behaviour of the two limbs when they oscillate following an external time giver, either alone or coupled together. Results Ten subjects oscillated their right hand and foot both alone and coupled (iso- or antidirectionally, paced by a metronome. Wrist and ankle angular position and Electromyograms (EMG from the respective flexor and extensor muscles were recorded. Three phase delays were measured: i the clk-mov delay, between the clock (metronome beat and the oscillation peak; ii the neur (neural delay, between the clock and the motoneurone excitatory input, as inferred from the EMG onset; and iii the mech (mechanical delay between the EMG onset and the corresponding point of the limb oscillation. During uncoupled oscillations (0.4 Hz to 3.0 Hz, the mech delay increased from -7° to -111° (hand and from -4° to -83° (foot. In contrast, the clk-mov delay remained constant and close to zero in either limb since a progressive advance of the motoneurone activation on the pacing beat (neur advance compensated for the increasing mech delay. Adding an inertial load to either extremity induced a frequency dependent increase of the limb mechanical delay that could not be completely compensated by the increase of the neural phase advance, resulting in a frequency dependent increment of clk-mov delay of the hampered limb. When limb oscillations were iso- or antidirectionally coupled, either in the loaded or unloaded condition, the three delays did not significantly change with respect to values measured when limbs were moved separately. Conclusion The absence of any significant effect of limb coupling on
Farm Service Agency, Department of Agriculture — The NAIP 2015 Imagery Feedback web application allows users to make comments and observations about the quality of the 2015 National Agriculture Imagery Program...
Farm Service Agency, Department of Agriculture — Map showing coverage of current Resource imagery projects. High resolution/large scale Resource imagery is typically acquired for the U.S. Forest Service and other...
... All Topics A-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 Stiff Hands Email to a friend * required fields ...
... All Topics A-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 Hand Infections Email to a friend * required fields ...
Kim, Hongsuk H.; Elman, Gregory C.
Sets of Thematic Mapper (TM) imagery taken over the Washington, DC metropolitan area during the months of November, March and May were converted into a form of ground reflectance imagery. This conversion was accomplished by adjusting the incident sunlight and view angles and by applying a pixel-by-pixel correction for atmospheric effects. Seasonal color changes of the area can be better observed when such normalization is applied to space imagery taken in time series. In normalized imagery, the grey scale depicts variations in surface reflectance and tonal signature of multi-band color imagery can be directly interpreted for quantitative information of the target.
Full Text Available In this study, an earphone-type interface named “earable TEMPO” was developed for hands-free operation, wherein the user can control the device by simply pushing the tongue against the roof of the mouth for about one second. This interface can be used to start and stop the music from a portable audio player. The earable TEMPO uses an earphone-type sensor equipped with a light emitting diode (LED and a phototransistor to optically measure shape variations that occur in the external auditory meatus when the tongue is pressed against the roof of the mouth. To evaluate the operation of the earable TEMPO, experiments were performed on five subjects (men and women aged 22–58 while resting, chewing gum (representing mastication, and walking. The average accuracy was 100% while resting and chewing and 99% while walking. The precision was 100% under all conditions. The average recall value of the five subjects was 92%, 90%, and 48% while resting, masticating, and walking, respectively. All subjects were reliably able to perform the action of pressing the tongue against the roof of the mouth. The measured shape variations in the ear canal were highly reproducible, indicating that this method is suitable for various applications such as controlling a portable audio player.
Full Text Available This article offers an anthropological analysis of a conflict over the use of a set of 'healing chains' and other focal objects kept in the Orthodox Christian monastery of Saints Kosmas and Damian in Kuklen, Bulgaria. In a nutshell, the conflict captures the leading religious imageries propagated by the custodians of the monastery on the one hand, and the spiritual leaders of a new religious movement, so-called Deunovians, on the other. The analysis helps situate some of the significant changes currently affecting the religious culture of Orthodox Christians in Bulgaria within a broader social and cultural context.
... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is ... Hand Therapist? Media Find a Hand Surgeon Home Anatomy ... DESCRIPTION The bones of the hand serve as a framework. This framework supports the muscles that make the wrist and fingers move. When ...
Patel, Vrajeshri; Thukral, Poojita; Burns, Martin K; Florescu, Ionut; Chandramouli, Rajarathnam; Vinjamuri, Ramana
Recently, the need for more secure identity verification systems has driven researchers to explore other sources of biometrics. This includes iris patterns, palm print, hand geometry, facial recognition, and movement patterns (hand motion, gait, and eye movements). Identity verification systems may benefit from the complexity of human movement that integrates multiple levels of control (neural, muscular, and kinematic). Using principal component analysis, we extracted spatiotemporal hand synergies (movement synergies) from an object grasping dataset to explore their use as a potential biometric. These movement synergies are in the form of joint angular velocity profiles of 10 joints. We explored the effect of joint type, digit, number of objects, and grasp type. In its best configuration, movement synergies achieved an equal error rate of 8.19%. While movement synergies can be integrated into an identity verification system with motion capture ability, we also explored a camera-ready version of hand synergies-postural synergies. In this proof of concept system, postural synergies performed well, but only when specific postures were chosen. Based on these results, hand synergies show promise as a potential biometric that can be combined with other hand-based biometrics for improved security.
Full Text Available Recently, the need for more secure identity verification systems has driven researchers to explore other sources of biometrics. This includes iris patterns, palm print, hand geometry, facial recognition, and movement patterns (hand motion, gait, and eye movements. Identity verification systems may benefit from the complexity of human movement that integrates multiple levels of control (neural, muscular, and kinematic. Using principal component analysis, we extracted spatiotemporal hand synergies (movement synergies from an object grasping dataset to explore their use as a potential biometric. These movement synergies are in the form of joint angular velocity profiles of 10 joints. We explored the effect of joint type, digit, number of objects, and grasp type. In its best configuration, movement synergies achieved an equal error rate of 8.19%. While movement synergies can be integrated into an identity verification system with motion capture ability, we also explored a camera-ready version of hand synergies—postural synergies. In this proof of concept system, postural synergies performed well, but only when specific postures were chosen. Based on these results, hand synergies show promise as a potential biometric that can be combined with other hand-based biometrics for improved security.
Pfurtscheller, G.; Scherer, R.; Müller-Putz, G.R.; Lopes da Silva, F.H.
Multi-channel electroencephalography recordings have shown that a visual cue, indicating right hand, left hand or foot motor imagery, can induce a short-lived brain state in the order of about 500 ms. In the present study, 10 able-bodied subjects without any motor imagery experience (naive subjects)
Pesyna, Colin; Pundi, Krishna; Flanders, Martha
The neural control of hand movement involves coordination of the sensory, motor, and memory systems. Recent studies have documented the motor coordinates for hand shape, but less is known about the corresponding patterns of somatosensory activity. To initiate this line of investigation, the present study characterized the sense of hand shape by evaluating the influence of differences in the amount of grasping or twisting force, and differences in forearm orientation. Human subjects were asked to use the left hand to report the perceived shape of the right hand. In the first experiment, six commonly grasped items were arranged on the table in front of the subject: bottle, doorknob, egg, notebook, carton, and pan. With eyes closed, subjects used the right hand to lightly touch, forcefully support, or imagine holding each object, while 15 joint angles were measured in each hand with a pair of wired gloves. The forces introduced by supporting or twisting did not influence the perceptual report of hand shape, but for most objects, the report was distorted in a consistent manner by differences in forearm orientation. Subjects appeared to adjust the intrinsic joint angles of the left hand, as well as the left wrist posture, so as to maintain the imagined object in its proper spatial orientation. In a second experiment, this result was largely replicated with unfamiliar objects. Thus, somatosensory and motor information appear to be coordinated in an object-based, spatial-coordinate system, sensitive to orientation relative to gravitational forces, but invariant to grasp forcefulness.
... from conditions such as carpal tunnel syndrome and tennis elbow , as well as from chronic problems such as ... Tools Advice from a Certified Hand Therapist on Tennis Elbow Advice from a Certified Hand Therapist: Living with( ...
Gao, Lin; Cheng, Wei; Zhang, Jinhua; Wang, Jue
Brain-computer interface (BCI) systems provide an alternative communication and control approach for people with limited motor function. Therefore, the feature extraction and classification approach should differentiate the relative unusual state of motion intention from a common resting state. In this paper, we sought a novel approach for multi-class classification in BCI applications. We collected electroencephalographic (EEG) signals registered by electrodes placed over the scalp during left hand motor imagery, right hand motor imagery, and resting state for ten healthy human subjects. We proposed using the Kolmogorov complexity (Kc) for feature extraction and a multi-class Adaboost classifier with extreme learning machine as base classifier for classification, in order to classify the three-class EEG samples. An average classification accuracy of 79.5% was obtained for ten subjects, which greatly outperformed commonly used approaches. Thus, it is concluded that the proposed method could improve the performance for classification of motor imagery tasks for multi-class samples. It could be applied in further studies to generate the control commands to initiate the movement of a robotic exoskeleton or orthosis, which finally facilitates the rehabilitation of disabled people.
... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is ... Hand Therapist? Media Find a Hand Surgeon Home Anatomy Bones Joints Muscles Nerves Vessels Tendons Anatomy The upper extremity is ...
Konnaris, C; Gavriel, C; Thomik, AAC; Aldo Faisal, A
Our dexterous hand is a fundmanetal human feature that distinguishes us from other animals by enabling us to go beyond grasping to support sophisticated in-hand object manipulation. Our aim was the design of a dexterous anthropomorphic robotic hand that matches the human hand's 24 degrees of freedom, under-actuated by seven motors. With the ability to replicate human hand movements in a naturalistic manner including in-hand object manipulation. Therefore, we focused on the development of a no...
Zhang, Shen; Zheng, Yanchun; Wang, Daifa; Wang, Ling; Ma, Jianai; Zhang, Jing; Xu, Weihao; Li, Deyu; Zhang, Dan
Motor imagery is one of the most investigated paradigms in the field of brain-computer interfaces (BCIs). The present study explored the feasibility of applying a common spatial pattern (CSP)-based algorithm for a functional near-infrared spectroscopy (fNIRS)-based motor imagery BCI. Ten participants performed kinesthetic imagery of their left- and right-hand movements while 20-channel fNIRS signals were recorded over the motor cortex. The CSP method was implemented to obtain the spatial filters specific for both imagery tasks. The mean, slope, and variance of the CSP filtered signals were taken as features for BCI classification. Results showed that the CSP-based algorithm outperformed two representative channel-wise methods for classifying the two imagery statuses using either data from all channels or averaged data from imagery responsive channels only (oxygenated hemoglobin: CSP-based: 75.3±13.1%; all-channel: 52.3±5.3%; averaged: 64.8±13.2%; deoxygenated hemoglobin: CSP-based: 72.3±13.0%; all-channel: 48.8±8.2%; averaged: 63.3±13.3%). Furthermore, the effectiveness of the CSP method was also observed for the motor execution data to a lesser extent. A partial correlation analysis revealed significant independent contributions from all three types of features, including the often-ignored variance feature. To our knowledge, this is the first study demonstrating the effectiveness of the CSP method for fNIRS-based motor imagery BCIs. Copyright © 2017 Elsevier B.V. All rights reserved.
Hand osteoarthritis (OA) is a common chronic disorder causing pain and limitation of mobility of affected joints. The prevalence of hand OA increases with age and more often affects females. Clinical signs obviously do not correlate with radiographic findings - symptomatic hand OA affects approximately 26 % of adult subjects, but radiographic changes can be found in up to two thirds of females and half of males older than 55 years.Disease course differ among individual patients. Hand OA is a heterogeneous disease. Nodal hand OA is the most common subtype affecting interphalangeal joints, thumb base OA affects first carpometacarpal joint. Erosive OA represents a specific subtype of hand OA, which is associated with joint inflammation, more pain, functional limitation and erosive findings on radiographs.Treatment of OA is limited. Analgesics and nonsteroidal anti-inflammatory drugs are the only agents reducing symptoms. New insights into the pathogenesis of disease should contribute to the development of novel effective treatment of hand OA.
Steenbergen, B.; Nimwegen, M.L. van; Crajé, M.C.
A recent study showed that motor imagery was compromised after right congenital hemiparesis. In that study, posture of the displayed stimuli and the actual posture of the hand making the response were incongruent. Ample evidence exists that such an incongruency may negatively influence laterality
There are different motor sets, which a human subject can be in or act from: he or she can be in a self-initiated voluntary movement set (action) or in a response set (re-action). Also, imagery sets are available that are necessary for the acquisition and practice of skill. Most important are such imagery sets for rehearsal in theatre, dance, music, sports, combat, etc.
Calhoun, Tracy; Melendrez, Dave
The Human Exploration Science Office (KX) provides leadership for NASA's Imagery Integration (Integration 2) Team, an affiliation of experts in the use of engineering-class imagery intended to monitor the performance of launch vehicles and crewed spacecraft in flight. Typical engineering imagery assessments include studying and characterizing the liftoff and ascent debris environments; launch vehicle and propulsion element performance; in-flight activities; and entry, landing, and recovery operations. Integration 2 support has been provided not only for U.S. Government spaceflight (e.g., Space Shuttle, Ares I-X) but also for commercial launch providers, such as Space Exploration Technologies Corporation (SpaceX) and Orbital Sciences Corporation, servicing the International Space Station. The NASA Integration 2 Team is composed of imagery integration specialists from JSC, the Marshall Space Flight Center (MSFC), and the Kennedy Space Center (KSC), who have access to a vast pool of experience and capabilities related to program integration, deployment and management of imagery assets, imagery data management, and photogrammetric analysis. The Integration 2 team is currently providing integration services to commercial demonstration flights, Exploration Flight Test-1 (EFT-1), and the Space Launch System (SLS)-based Exploration Missions (EM)-1 and EM-2. EM-2 will be the first attempt to fly a piloted mission with the Orion spacecraft. The Integration 2 Team provides the customer (both commercial and Government) with access to a wide array of imagery options - ground-based, airborne, seaborne, or vehicle-based - that are available through the Government and commercial vendors. The team guides the customer in assembling the appropriate complement of imagery acquisition assets at the customer's facilities, minimizing costs associated with market research and the risk of purchasing inadequate assets. The NASA Integration 2 capability simplifies the process of securing one
Bruno, Valentina; Fossataro, Carlotta; Garbarini, Francesca
Motor imagery (MI) is the mental simulation of an action without any overt movement. Functional evidences show that brain activity during MI and motor execution (ME) largely overlaps. However, the role of the primary motor cortex (M1) during MI is controversial. Effective connectivity techniques show a facilitation on M1 during ME and an inhibition during MI, depending on whether an action should be performed or suppressed. Conversely, Transcranial Magnetic Stimulation (TMS) studies report facilitatory effects during both ME and MI. The present TMS study shed light on MI mechanisms, by manipulating the instructions given to the participants. In both Experimental and Control groups, participants were asked to mentally simulate a finger-thumb opposition task, but only the Experimental group received the explicit instruction to avoid any unwanted fingers movements. The amplitude of motor evoked potentials (MEPs) to TMS during MI was compared between the two groups. If the M1 facilitation actually pertains to MI per se, we should have expected to find it, irrespective of the instructions. Contrariwise, we found opposite results, showing facilitatory effects (increased MEPs amplitude) in the Control group and inhibitory effects (decreased MEPs amplitude) in the Experimental group. Control experiments demonstrated that the inhibitory effect was specific for the M1 contralateral to the hand performing the MI task and that the given instructions did not compromise the subjects' MI abilities. The present findings suggest a crucial role of motor inhibition when a "pure" MI task is performed and the subjects are explicitly instructed to avoid overt movements. Copyright © 2018 Elsevier Ltd. All rights reserved.
National Oceanic and Atmospheric Administration, Department of Commerce — This digital ortho-imagery dataset is a survey of coastal California. The project area consists of approximately 3774 square miles. The project design of the digital...
National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is in response to natural disasters. The aerial photography missions were conducted by the NOAA Remote Sensing Division. The majority...
The Omni-Hand was developed by Ross-Hime Designs, Inc. for Marshall Space Flight Center (MSFC) under a Small Business Innovation Research (SBIR) contract. The multiple digit hand has an opposable thumb and a flexible wrist. Electric muscles called Minnacs power wrist joints and the interchangeable digits. Two hands have been delivered to NASA for evaluation for potential use on space missions and the unit is commercially available for applications like hazardous materials handling and manufacturing automation. Previous SBIR contracts resulted in the Omni-Wrist and Omni-Wrist II robotic systems, which are commercially available for spray painting, sealing, ultrasonic testing, as well as other uses.
A bowel movement is the last stop in the movement of food through your digestive tract. Your stool passes out of ... what you eat and drink. Sometimes a bowel movement isn't normal. Diarrhea happens when stool passes ...
Atzori, Manfredo; Gijsberts, Arjan; Caputo, Barbara; Muller, Henning
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.
Dorota M. Jankowska
Full Text Available Over the decades, creativity and imagination research developed in parallel, but they surprisingly rarely intersected. This paper introduces a new theoretical model of creative imagination, which bridges creativity and imagination research, as well as presents a new psychometric instrument, called the Test of Creative Imagery Abilities (TCIA, developed to measure creative imagery abilities understood in accordance with this model. Creative imagination is understood as constituted by three interrelated components: vividness (the ability to create images characterized by a high level of complexity and detail, originality (the ability to produce unique imagery, and transformativeness (the ability to control imagery. TCIA enables valid and reliable measurement of these three groups of abilities, yielding the general score of imagery abilities and at the same time making profile analysis possible. We present the results of eight studies on a total sample of more than 1,700 participants, showing the factor structure of TCIA using confirmatory factor analysis, as well as provide data confirming this instrument’s validity and reliability. The availability of TCIA for interested researchers may result in new insights and possibilities of integrating the fields of creativity and imagination science.
Anuar, Nurwina; Williams, Sarah E; Cumming, Jennifer
The present study aimed to examine whether physical and environment elements of PETTLEP imagery relate to the ability to image five types of sport imagery (i.e. skill, strategy, goal, affect and mastery). Two hundred and ninety participants (152 males, 148 females; M age = 20.24 years, SD = 4.36) from various sports completed the Sport Imagery Ability Questionnaire (SIAQ), and a set of items designed specifically for the study to assess how frequently participants incorporate physical (e.g. 'I make small movements or gestures during the imagery') and environment (e.g. 'I image in the real training/competition environment') elements of PETTLEP imagery. Structural equation modelling tested a hypothesised model in which imagery priming (i.e. the best fitting physical and environment elements) significantly and positively predicted imagery ability of the different imagery types (skill, β = 0.38; strategy, β = 0.23; goal, β = 0.21; affect, β = 0.25; mastery, β = 0.22). The model was a good fit to the data: χ 2 (174) = 263.87, p environment elements is associated with better skill, strategy, goal, affect and mastery imagery ability. The findings extend models of imagery use by indicating that how athletes images may influence their imagery ability.
Williams, Jacqueline; Reid, Susan M.; Reddihough, Dinah S.; Anderson, Vicki
In addition to motor execution problems, children with hemiplegia have motor planning deficits, which may stem from poor motor imagery ability. This study aimed to provide a greater understanding of motor imagery ability in children with hemiplegia using the hand rotation task. Three groups of children, aged 8-12 years, participated: right…
van der Lubbe, Rob; Sobierajewicz, Jagna; Jongsma, Marijtje; Przekoracka-Krawczyk, Anna
Motor imagery may be defined as the generation of an image of the acting self that lacks the final execution of a movement. This image is thought to be a simulation of the intended action from a first-person perspective. Recent studies with a Go/NoGo version of the discrete sequence production
Lovchik, Christopher Scott (Inventor); Diftler, Myron A. (Inventor)
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.
McCoy, Scott W.; Coe, Jeffrey A.; Kean, Jason W.; Tucker, Greg E.; Staley, Dennis M.; Wasklewicz, Thad A.
Debris flows initiated by surface-water runoff during short duration, moderate- to high-intensity rainfall are common in steep, rocky, and sparsely vegetated terrain. Yet large uncertainties remain about the potential for a flow to grow through entrainment of loose debris, which make formulation of accurate mechanical models of debris-flow routing difficult. Using a combination of in situ measurements of debris flow dynamics, video imagery, tracer rocks implanted with passive integrated transponders (PIT) and pre- and post-flow 2-cm resolution digital terrain models (terrain data presented in a companion paper by STALEY et alii, 2011), we investigated the entrainment and transport response of debris flows at Chalk Cliffs, CO, USA. Four monitored events during the summer of 2009 all initiated from surface-water runoff, generally less than an hour after the first measurable rain. Despite reach-scale morphology that remained relatively constant, the four flow events displayed a range of responses, from long-runout flows that entrained significant amounts of channel sediment and dammed the main-stem river, to smaller, short-runout flows that were primarily depositional in the upper basin. Tracer-rock travel-distance distributions for these events were bimodal; particles either remained immobile or they travelled the entire length of the catchment. The long-runout, large-entrainment flow differed from the other smaller flows by the following controlling factors: peak 10-minute rain intensity; duration of significant flow in the channel; and to a lesser extent, peak surge depth and velocity. Our growing database of natural debris-flow events can be used to develop linkages between observed debris-flow transport and entrainment responses and the controlling rainstorm characteristics and flow properties.
Ibler, K.S.; Jemec, G.B.E.; Flyvholm, M.-A.
Background. Healthcare workers are at increased risk of developing hand eczema. Objectives. To investigate the prevalence and severity of self-reported hand eczema, and to relate the findings to demographic data, occupation, medical speciality, wards, shifts, and working hours. Patients/materials......Background. Healthcare workers are at increased risk of developing hand eczema. Objectives. To investigate the prevalence and severity of self-reported hand eczema, and to relate the findings to demographic data, occupation, medical speciality, wards, shifts, and working hours. Patients...... dermatitis, younger age, male sex (male doctors), and working hours. Eighty nine per cent of subjects reported mild/moderate lesions. Atopic dermatitis was the only factor significantly related to severity. Sick leave was reported by 8% of subjects, and notification to the authorities by 12%. Conclusions...... or severity, but cultural differences between professions with respect to coping with the eczema were significant. Atopic dermatitis was related to increased prevalence and severity, and preventive efforts should be made for healthcare workers with atopic dermatitis....
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.
Farm Service Agency, Department of Agriculture — The NAIP 2015 Imagery Feedback map allows users to make comments and observations about the quality of the 2015 National Agriculture Imagery Program (NAIP)...
Farm Service Agency, Department of Agriculture — The NAIP 2017 Imagery Feedback map allows users to make comments and observations about the quality of the 2017 National Agriculture Imagery Program (NAIP)...
Wesp, R; Hesse, J; Keutmann, D; Wheaton, K
Recent theories suggest alternatives to the commonly held belief that the sole role of gestures is to communicate meaning directly to listeners. Evidence suggests that gestures may serve a cognitive function for speakers, possibly acting as lexical primes. We observed that participants gestured more often when describing a picture from memory than when the picture was present and that gestures were not influenced by manipulating eye contact of a listener. We argue that spatial imagery serves a short-term memory function during lexical search and that gestures may help maintain spatial images. When spatial imagery is not necessary, as in conditions of direct visual stimulation, reliance on gestures is reduced or eliminated.
Dinstein, Ilan; Thomas, Cibu; Humphreys, Kate; Minshew, Nancy; Behrmann, Marlene; Heeger, David J
It has been proposed that individuals with autism have difficulties understanding the goals and intentions of others because of a fundamental dysfunction in the mirror neuron system. Here, however, we show that individuals with autism exhibited not only normal fMRI responses in mirror system areas during observation and execution of hand movements but also exhibited typical movement-selective adaptation (repetition suppression) when observing or executing the same movement repeatedly. Movement selectivity is a defining characteristic of neurons involved in movement perception, including mirror neurons, and, as such, these findings argue against a mirror system dysfunction in autism. Copyright 2010 Elsevier Inc. All rights reserved.
Hayashi, M; Katoh, K; Hori, T
The relationships between hypnagogic imagery and EEG activity were studied. 7 subjects (4 women and 3 men) reported the content of hypnagogic imagery every minute and the hypnagogic EEGs were classified into 5 stages according to Hori's modified criteria. The content of the hypnagogic imagery changed as a function of the hypnagogic EEG stages.
Pelgrims, Barbara; Michaux, Nicolas; Olivier, Etienne; Andres, Michael
Motor imagery (MI) mostly activates the same brain regions as movement execution (ME) including the primary motor cortex (Brodmann area 4, BA4). However, whether BA4 is functionally relevant for MI remains controversial. The finding that MI tasks are impaired by BA4 virtual lesions induced by transcranial magnetic stimulation (TMS) supports this view, though previous studies do not permit to exclude that BA4 is also involved in other processes such as hand recognition. Additionally, previous works largely underestimated the possible negative consequences of TMS-induced muscle twitches on MI task performance. Here we investigated the role of BA4 in MI by interfering with the function of the left or right BA4 in healthy subjects performing a MI task in which they had to make laterality judgements on rotated hand drawings. We used a subthreshold repetitive TMS protocol and monitored electromyographic activity to exclude undesirable effects of hand muscle twitches. We found that BA4 virtual lesions selectively increased reaction times in laterality judgments on hand drawings, leaving unaffected a task of equal difficulty, involving judgments on letters. Interestingly, the effects of virtual lesions of left and right BA4 on MI task performance were the same irrespective of the laterality (left/right) of hand drawings. A second experiment allowed us to rule out the possibility that BA4 lesions affect visual or semantic processing of hand drawings. Altogether, these results indicate that BA4 contribution to MI tasks is specifically related to the mental simulation process and further emphasize the functional coupling between ME and MI. Copyright © 2010 Wiley-Liss, Inc.
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of full-disk images of the sun in Calcium (Ca) II K wavelength (393.4 nm). Ca II K imagery reveal magnetic structures of the sun from about 500...
Dinstein, Ilan; Thomas, Cibu; Humphreys, Kate; Minshew, Nancy; Behrmann, Marlene; Heeger, David J.
It has been proposed that individuals with autism have difficulties understanding the goals and intentions of others because of a fundamental dysfunction in the mirror neuron system. Here, however, we show that individuals with autism exhibited not only normal fMRI responses in mirror system areas during observation and execution of hand movements, but also exhibited typical movement-selective adaptation (repetition suppression) when observing or executing the same movement repeatedly. Moveme...
Lebon, Florent; Horn, Ulrike; Domin, Martin; Lotze, Martin
Motor imagery (MI) is the mental simulation of action frequently used by professionals in different fields. However, with respect to performance, well-controlled functional imaging studies on MI training are sparse. We investigated changes in fMRI representation going along with performance changes of a finger sequence (error and velocity) after MI training in 48 healthy young volunteers. Before training, we tested the vividness of kinesthetic and visual imagery. During tests, participants were instructed to move or to imagine moving the fingers of the right hand in a specific order. During MI training, participants repeatedly imagined the sequence for 15 min. Imaging analysis was performed using a full-factorial design to assess brain changes due to imagery training. We also used regression analyses to identify those who profited from training (performance outcome and gain) with initial imagery scores (vividness) and fMRI activation magnitude during MI at pre-test (MI pre ). After training, error rate decreased and velocity increased. We combined both parameters into a common performance index. FMRI activation in the left inferior parietal lobe (IPL) was associated with MI and increased over time. In addition, fMRI activation in the right IPL during MI pre was associated with high initial kinesthetic vividness. High kinesthetic imagery vividness predicted a high performance after training. In contrast, occipital activation, associated with visual imagery strategies, showed a negative predictive value for performance. Our data echo the importance of high kinesthetic vividness for MI training outcome and consider IPL as a key area during MI and through MI training. © 2018 Wiley Periodicals, Inc.
... Loss of coordination; Coordination impairment; Ataxia; Clumsiness; Uncoordinated movement ... Smooth graceful movement requires a balance between different muscle groups. A part of the brain called the cerebellum manages this balance.
Full Text Available Avulsion of skin from the hand or fingers is an injury that has a dramatic presentation. The entire musculo-skeletal unit of the finger is intact, and the patient can often move the parts of his naked hand quite normally. The challenge for the reconstructive surgeon lies in resurfacing the hand or finger with a good quality pliable sensate skin cover while preserving the movements and function of the hand. Traditionally, skin grafting has been the standard method of reconstruction in such injuries. However, skin grafting does have many disadvantages, too. This article deals with the features of such injuries, management protocols and other reconstructive options available in the armamentarium of the hand surgeon.
Maamer Slimani, David Tod, Helmi Chaabene, Bianca Miarka, Karim Chamari
Full Text Available The aims of the present review were to (i provide a critical overview of the current literature on the effects of mental imagery on muscular strength in healthy participants and patients with immobilization of the upper extremity (i.e., hand and anterior cruciate ligament (ACL, (ii identify potential moderators and mediators of the “mental imagery-strength performance” relationship and (iii determine the relative contribution of electromyography (EMG and brain activities, neural and physiological adaptations in the mental imagery-strength performance relationship. This paper also discusses the theoretical and practical implications of the contemporary literature and suggests possible directions for future research. Overall, the results reveal that the combination of mental imagery and physical practice is more efficient than, or at least comparable to, physical execution with respect to strength performance. Imagery prevention intervention was also effective in reducing of strength loss after short-term muscle immobilization and ACL. The present review also indicates advantageous effects of internal imagery (range from 2.6 to 136.3% for strength performance compared with external imagery (range from 4.8 to 23.2%. Typically, mental imagery with muscular activity was higher in active than passive muscles, and imagining “lifting a heavy object” resulted in more EMG activity compared with imagining “lifting a lighter object”. Thus, in samples of students, novices, or youth male and female athletes, internal mental imagery has a greater effect on muscle strength than external mental imagery does. Imagery ability, motivation, and self-efficacy have been shown to be the variables mediating the effect of mental imagery on strength performance. Finally, the greater effects of internal imagery than those of external imagery could be explained in terms of neural adaptations, stronger brain activation, higher muscle excitation, greater somatic
Rosanne Lynn Rademaker
Full Text Available Visual imagery has been closely linked to brain mechanisms involved in perception. Can visual imagery, like visual perception, improve by means of training? Previous research has demonstrated that people can reliably evaluate the vividness of single episodes of sensory imagination – might the metacognition of imagery also improve over the course of training? We had participants imagine colored Gabor patterns for an hour a day, over the course of five consecutive days, and again two weeks after training. Participants rated the subjective vividness and effort of their mental imagery on each trial. The influence of imagery on subsequent binocular rivalry dominance was taken as our measure of imagery strength. We found no overall effect of training on imagery strength. Training did, however, improve participant’s metacognition of imagery. Trial-by-trial ratings of vividness gained predictive power on subsequent rivalry dominance as a function of training. These data suggest that, while imagery strength might be immune to training in the current context, people’s metacognitive understanding of mental imagery can improve with practice.
On this poster some reasons of slope movements on the territory of the Slovak Republic are presented. Slope movements induced deterioration of land and forests, endangering of towns villages, and communications as well as hydro-engineering structures. Methods of preventing and stabilisation of slope movements are presented.
Full Text Available Research in sports, dance and rehabilitation has shown that Basic Action Concepts (BACs are fundamental building blocks of mental action representations. BACs are based on chunked body postures related to common functions for realizing action goals. In this paper, we outline issues in research methodology and an experimental method, SDA-M (structural dimensional analysis of mental representation, to assess action-relevant representational structures that reflect the organization of BACs. The SDA-M reveals a strong relationship between cognitive representation and performance if complex actions are performed. We show how the SDA-M can improve motor imagery training and how it contributes to our understanding of coaching processes. The SDA-M capitalizes on the objective measurement of individual mental movement representations before training and the integration of these results into the motor imagery training. Such motor imagery training based on mental representations has been applied successfully in professional sports such as golf, volleyball, gymnastics, windsurfing, and recently in the rehabilitation of patients who have suffered a stroke.
Adams, I.L.; Steenbergen, B.; Lust, J.M.; Smits-Engelsman, B.C.
BACKGROUND: Previous studies have shown that the predictive control of movements is impaired in children with Developmental Coordination Disorder (DCD), most likely due to a deficit in the internal modeling of movements. Motor imagery paradigms have been used to test this internal modeling deficit.
Adams, I.L.J.; Steenbergen, B.; Lust, J.M.; Smits-Engelsman, B.C.M.
Background: Previous studies have shown that the predictive control of movements is impaired in children with Developmental Coordination Disorder (DCD), most likely due to a deficit in the internal modeling of movements. Motor imagery paradigms have been used to test this internal modeling deficit.
Worthem, A. V.; Madore, B.; Imahori, G.; Woolard, J.; Sellars, J.; Halbach, A.; Helmricks, D.; Quarrick, J.
NOAA's National Geodetic Survey (NGS) and Remote Sensing Division acquired and rapidly disseminated emergency response imagery related to the three recent hurricanes Harvey, Irma, and Maria. Aerial imagery was collected using a Trimble Digital Sensor System, a high-resolution digital camera, by means of NOAA's King Air 350ER and DeHavilland Twin Otter (DHC-6) Aircraft. The emergency response images are used to assess the before and after effects of the hurricanes' damage. The imagery aids emergency responders, such as FEMA, Coast Guard, and other state and local governments, in developing recovery strategies and efforts by prioritizing areas most affected and distributing appropriate resources. Collected imagery is also used to provide damage assessment for use in long-term recovery and rebuilding efforts. Additionally, the imagery allows for those evacuated persons to see images of their homes and neighborhoods remotely. Each of the individual images are processed through ortho-rectification and merged into a uniform mosaic image. These remotely sensed datasets are publically available, and often used by web-based map servers as well as, federal, state, and local government agencies. This poster will show the imagery collected for these three hurricanes and the processes involved in getting data quickly into the hands of those that need it most.
Scherer, Reinhold; Faller, Josef; Friedrich, Elisabeth V C; Opisso, Eloy; Costa, Ursula; Kübler, Andrea; Müller-Putz, Gernot R
Brain-computer interfaces (BCIs) translate oscillatory electroencephalogram (EEG) patterns into action. Different mental activities modulate spontaneous EEG rhythms in various ways. Non-stationarity and inherent variability of EEG signals, however, make reliable recognition of modulated EEG patterns challenging. Able-bodied individuals who use a BCI for the first time achieve - on average - binary classification performance of about 75%. Performance in users with central nervous system (CNS) tissue damage is typically lower. User training generally enhances reliability of EEG pattern generation and thus also robustness of pattern recognition. In this study, we investigated the impact of mental tasks on binary classification performance in BCI users with central nervous system (CNS) tissue damage such as persons with stroke or spinal cord injury (SCI). Motor imagery (MI), that is the kinesthetic imagination of movement (e.g. squeezing a rubber ball with the right hand), is the "gold standard" and mainly used to modulate EEG patterns. Based on our recent results in able-bodied users, we hypothesized that pair-wise combination of "brain-teaser" (e.g. mental subtraction and mental word association) and "dynamic imagery" (e.g. hand and feet MI) tasks significantly increases classification performance of induced EEG patterns in the selected end-user group. Within-day (How stable is the classification within a day?) and between-day (How well does a model trained on day one perform on unseen data of day two?) analysis of variability of mental task pair classification in nine individuals confirmed the hypothesis. We found that the use of the classical MI task pair hand vs. feed leads to significantly lower classification accuracy - in average up to 15% less - in most users with stroke or SCI. User-specific selection of task pairs was again essential to enhance performance. We expect that the gained evidence will significantly contribute to make imagery-based BCI technology
Full Text Available Brain-computer interfaces (BCIs translate oscillatory electroencephalogram (EEG patterns into action. Different mental activities modulate spontaneous EEG rhythms in various ways. Non-stationarity and inherent variability of EEG signals, however, make reliable recognition of modulated EEG patterns challenging. Able-bodied individuals who use a BCI for the first time achieve - on average - binary classification performance of about 75%. Performance in users with central nervous system (CNS tissue damage is typically lower. User training generally enhances reliability of EEG pattern generation and thus also robustness of pattern recognition. In this study, we investigated the impact of mental tasks on binary classification performance in BCI users with central nervous system (CNS tissue damage such as persons with stroke or spinal cord injury (SCI. Motor imagery (MI, that is the kinesthetic imagination of movement (e.g. squeezing a rubber ball with the right hand, is the "gold standard" and mainly used to modulate EEG patterns. Based on our recent results in able-bodied users, we hypothesized that pair-wise combination of "brain-teaser" (e.g. mental subtraction and mental word association and "dynamic imagery" (e.g. hand and feet MI tasks significantly increases classification performance of induced EEG patterns in the selected end-user group. Within-day (How stable is the classification within a day? and between-day (How well does a model trained on day one perform on unseen data of day two? analysis of variability of mental task pair classification in nine individuals confirmed the hypothesis. We found that the use of the classical MI task pair hand vs. feed leads to significantly lower classification accuracy - in average up to 15% less - in most users with stroke or SCI. User-specific selection of task pairs was again essential to enhance performance. We expect that the gained evidence will significantly contribute to make imagery-based BCI
Srzich, Alexander J; Byblow, Winston D; Stinear, James W; Cirillo, John; Anson, J Greg
Marked distortions in sense of agency can be induced by hypnosis in susceptible individuals, including alterations in subjective awareness of movement initiation and control. These distortions, with associated disability, are similar to those experienced with Conversion Disorder (CD), an observation that has led to the hypothesis that hypnosis and CD share causal mechanisms. The purpose of this review is to explore the relationships among motor imagery (MI), hypnotic susceptibility, and CD, then to propose how MI ability may contribute to hypnotic responding and CD. Studies employing subjective assessments of mental imagery have found little association between imagery abilities and hypnotic susceptibility. A positive association between imagery abilities and hypnotic susceptibility becomes apparent when objective measures of imagery ability are employed. A candidate mechanism to explain motor responses during hypnosis is kinaesthetic MI, which engages a strategy that involves proprioception or the "feel" of movement when no movement occurs. Motor suppression imagery (MSI), a strategy involving inhibition of movement, may provide an alternate objective measurable phenomenon that underlies both hypnotic susceptibility and CD. Evidence to date supports the idea that there may be a positive association between kinaesthetic MI ability and hypnotic susceptibility. Additional evidence supports a positive association between hypnotic susceptibility and CD. Disturbances in kinaesthetic MI performance in CD patients indicate that MI mechanisms may also underlie CD symptoms. Further investigation of the above relationships is warranted to explain these phenomena, and establish theoretical explanations underlying sense of agency. Copyright © 2016. Published by Elsevier Ltd.
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…
Aarts, P.B.M.; Jongerius, P.H.; Geerdink-van Nistelrooij, Y.A. van; Limbeek, J. van; Geurts, A.C.H.
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
Cacola, Priscila; Roberson, Jerroed; Gabbard, Carl
Studies show that as we enter older adulthood (greater than 64 years), our ability to mentally represent action in the form of using motor imagery declines. Using a chronometry paradigm to compare the movement duration of imagined and executed movements, we tested young-, middle-aged, and older adults on their ability to perform sequential finger…
Beudel, M.; Zijlstra, S.; Mulder, Th.; Zijdewind, I.; de Jong, B. M.
Secondary sensorimotor regions are involved in sensorimotor integration and movement preparation. These regions take part in parietal-premotor circuitry that is not only active during motor execution but also during movement observation and imagery. This activation particularly occurs when observed
Dystonia; Involuntary slow and twisting movements; Choreoathetosis; Leg and arm movements - uncontrollable; Arm and leg movements - uncontrollable; Slow involuntary movements of large muscle groups; Athetoid movements
Earnest, Darrell; Radtke, Susan; Scott, Siri
In this article, the authors first present the Hands Together! task. The mathematics in this problem concerns the relationship of hour and minute durations as reflected in the oft-overlooked proportional movements of the two hands of an analog clock. The authors go on to discuss the importance of problem solving in general. They then consider…
PATIENT EDUCATION patienteducation.osumc.edu Non-Drug Pain Relief: Imagery Relaxation helps lessen tension. One way to help decrease pain is to use imagery. Imagery is using your imagination to create a ...
Bozeman, Richard J., Jr.
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.
Roberts, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pope, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
This report details the work performed in FY11 under project LL11-GS-PD06, “Benchmark Imagery for Assessing Geospatial Semantic Extraction Algorithms.” The original LCP for the Benchmark Imagery project called for creating a set of benchmark imagery for verifying and validating algorithms that extract semantic content from imagery. More specifically, the first year was slated to deliver real imagery that had been annotated, the second year to deliver real imagery that had composited features, and the final year was to deliver synthetic imagery modeled after the real imagery.
Imagery rescripting is a powerful technique that can be successfully applied in the treatment of personality disorders. For personality disorders, imagery rescripting is not used to address intrusive images but to change the implicational meaning of schemas and childhood experiences that underlie the patient's problems. Various mechanisms that may…
Braun, Niclas; Emkes, Reiner; Thorne, Jeremy D; Debener, Stefan
Neurofeedback-guided motor imagery training (NF-MIT) has been suggested as a promising therapy for stroke-induced motor impairment. Whereas much NF-MIT research has aimed at signal processing optimization, the type of sensory feedback given to the participant has received less attention. Often the feedback signal is highly abstract and not inherently coupled to the mental act performed. In this study, we asked whether an embodied feedback signal is more efficient for neurofeedback operation than a non-embodiable feedback signal. Inspired by the rubber hand illusion, demonstrating that an artificial hand can be incorporated into one's own body scheme, we used an anthropomorphic robotic hand to visually guide the participants' motor imagery act and to deliver neurofeedback. Using two experimental manipulations, we investigated how a participant's neurofeedback performance and subjective experience were influenced by the embodiability of the robotic hand, and by the neurofeedback signal's validity. As pertains to embodiment, we found a promoting effect of robotic-hand embodiment in subjective, behavioral, electrophysiological and electrodermal measures. Regarding neurofeedback signal validity, we found some differences between real and sham neurofeedback in terms of subjective and electrodermal measures, but not in terms of behavioral and electrophysiological measures. This study motivates the further development of embodied feedback signals for NF-MIT.
Braun, Niclas; Emkes, Reiner; Thorne, Jeremy D.; Debener, Stefan
Neurofeedback-guided motor imagery training (NF-MIT) has been suggested as a promising therapy for stroke-induced motor impairment. Whereas much NF-MIT research has aimed at signal processing optimization, the type of sensory feedback given to the participant has received less attention. Often the feedback signal is highly abstract and not inherently coupled to the mental act performed. In this study, we asked whether an embodied feedback signal is more efficient for neurofeedback operation than a non-embodiable feedback signal. Inspired by the rubber hand illusion, demonstrating that an artificial hand can be incorporated into one’s own body scheme, we used an anthropomorphic robotic hand to visually guide the participants’ motor imagery act and to deliver neurofeedback. Using two experimental manipulations, we investigated how a participant’s neurofeedback performance and subjective experience were influenced by the embodiability of the robotic hand, and by the neurofeedback signal’s validity. As pertains to embodiment, we found a promoting effect of robotic-hand embodiment in subjective, behavioral, electrophysiological and electrodermal measures. Regarding neurofeedback signal validity, we found some differences between real and sham neurofeedback in terms of subjective and electrodermal measures, but not in terms of behavioral and electrophysiological measures. This study motivates the further development of embodied feedback signals for NF-MIT. PMID:27869190
Wang, Tao; He, Bin
The recognition of mental states during motor imagery tasks is crucial for EEG-based brain computer interface research. We have developed a new algorithm by means of frequency decomposition and weighting synthesis strategy for recognizing imagined right- and left-hand movements. A frequency range from 5 to 25 Hz was divided into 20 band bins for each trial, and the corresponding envelopes of filtered EEG signals for each trial were extracted as a measure of instantaneous power at each frequency band. The dimensionality of the feature space was reduced from 200 (corresponding to 2 s) to 3 by down-sampling of envelopes of the feature signals, and subsequently applying principal component analysis. The linear discriminate analysis algorithm was then used to classify the features, due to its generalization capability. Each frequency band bin was weighted by a function determined according to the classification accuracy during the training process. The present classification algorithm was applied to a dataset of nine human subjects, and achieved a success rate of classification of 90% in training and 77% in testing. The present promising results suggest that the present classification algorithm can be used in initiating a general-purpose mental state recognition based on motor imagery tasks.
Full Text Available ... has been rented. This feature is not available right now. Please try again later. Published on May ... 34 How The Clean Hands - Safe Hands System Works - Duration: 3:38. Clean Hands-Safe Hands 5, ...
van Bentum, J.S.; Sijbrandij, M.; Huibers, M.J.H.; Huisman, A.; Arntz, A.; Holmes, E.A.; Kerkhof, A.J.F.M.
Suicide and suicidal behavior are major public health concerns, and affect 3-9% of the population worldwide. Despite increased efforts for national suicide prevention strategies, there are still few effective interventions available for reducing suicide risk. In this article, we describe various
van Bentum, J.S.
Suicide and suicidal behavior are major public health concerns, and affect 3–9% of the population worldwide. Despite increased efforts for national suicide prevention strategies, there are still few effective interventions available for reducing suicide risk. In this article, we describe various
The author describes the development of protest movements in postwar Germay and outlines two essential overlapping 'flow cycles'. The first of these was characterised by the restaurative postwar years. It culminated and ended in the students' revolt. This revolt is at the same time the start of a second cycle of protest which encompasses all subsequent individual movement and is initated by an economic, political and sociocultural procrastination of modernisation. This cycle culminates in the late 70s and early 80s and clearly lost momentum over the last few years. The follwoing phases and themes are described profoundly: against restauration and armament in the 1950; the revolutionary impatience of the students' movement, politisation of everyday life by the womens' movement and citizens' action groups, antinuclear- and ecological movement, differentiation and stabilisation of the movement in the 70s and 80s; break-up and continuity in the German protest behaviour. The paper contains a detailed chronicle of protest activities since 1945. (orig.) [de
Full Text Available Accumulating evidence indicates that motor imagery and motor execution share common neural networks. Accordingly, mental practices in the form of motor imagery have been implemented in rehabilitation regimes of stroke patients with favorable results. Because direct monitoring of motor imagery is difficult, feedback of cortical activities related to motor imagery (neurofeedback could help to enhance efficacy of mental practice with motor imagery. To determine the feasibility and efficacy of a real-time neurofeedback system mediated by near-infrared spectroscopy (NIRS, two separate experiments were performed. Experiment 1 was used in five subjects to evaluate whether real-time cortical oxygenated hemoglobin signal feedback during a motor execution task correlated with reference hemoglobin signals computed off-line. Results demonstrated that the NIRS-mediated neurofeedback system reliably detected oxygenated hemoglobin signal changes in real-time. In Experiment 2, 21 subjects performed motor imagery of finger movements with feedback from relevant cortical signals and irrelevant sham signals. Real neurofeedback induced significantly greater activation of the contralateral premotor cortex and greater self-assessment scores for kinesthetic motor imagery compared with sham feedback. These findings suggested the feasibility and potential effectiveness of a NIRS-mediated real-time neurofeedback system on performance of kinesthetic motor imagery. However, these results warrant further clinical trials to determine whether this system could enhance the effects of mental practice in stroke patients.
Herholz, Sibylle C; Lappe, Claudia; Knief, Arne; Pantev, Christo
The present study investigated musical imagery in musicians and nonmusicians by means of magnetoencephalography (MEG). We used a new paradigm in which subjects had to continue familiar melodies in their mind and then judged if a further presented tone was a correct continuation of the melody. Incorrect tones elicited an imagery mismatch negativity (iMMN) in musicians but not in nonmusicians. This finding suggests that the MMN component can be based on an imagined instead of a sensory memory trace and that imagery of music is modulated by musical expertise.
Farm Service Agency, Department of Agriculture — The APFO Historical Availability ArcGIS Online web map provides an easy to use reference of what historical imagery is available by county from the Aerial...
Fred Walter Mast
Full Text Available We are able to extract detailed information from mental images that we were not explicitly aware of during encoding. For example, we can discover a new figure when we rotate a previously seen image in our mind. However, such discoveries are not really new but just new interpretations. In two recent publications, we have shown that mental imagery can lead to perceptual learning (Tartaglia et al., 2009, 2012. Observers imagined the central line of a bisection stimulus for thousands of trials. This training enabled observers to perceive bisection offsets that were invisible before training. Hence, it seems that perceptual learning via mental imagery leads to new percepts. We will argue, however, that these new percepts can occur only within known models. In this sense, perceptual learning via mental imagery exceeds new discoveries in mental images. Still, the effects of mental imagery on perceptual learning are limited. Only perception can lead to really new perceptual experience.
.... Army tactical applications. An important tactical application of infrared (IR) hyperspectral imagery is the detection of low-contrast targets, including those targets that may employ camouflage, concealment, and deception (CCD) techniques 1, 2...
Bradford, Brian N.; Sanchez-Reyes, Pedro J.
In this publication we present an automated detection method for ocean surface oil, like that which existed in the Gulf of Mexico as a result of the April 20, 2010 Deepwater Horizon drilling rig explosion. Regions of surface oil in airborne imagery are isolated using red, green, and blue bands from multispectral data sets. The oil shape isolation procedure involves a series of image processing functions to draw out the visual phenomenological features of the surface oil. These functions include selective color band combinations, contrast enhancement and histogram warping. An image segmentation process then separates out contiguous regions of oil to provide a raster mask to an analyst. We automate the detection algorithm to allow large volumes of data to be processed in a short time period, which can provide timely oil coverage statistics to response crews. Geo-referenced and mosaicked data sets enable the largest identified oil regions to be mapped to exact geographic coordinates. In our simulation, multispectral imagery came from multiple sources including first-hand data collected from the Gulf. Results of the simulation show the oil spill coverage area as a raster mask, along with histogram statistics of the oil pixels. A rough square footage estimate of the coverage is reported if the image ground sample distance is available.
Tang, Rixin; Zhu, Hong
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
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 limb...
Like all music performance, percussion playing requires high control over timing and sound properties. Specific to percussionists, however, is the need to adjust the movement to different instruments with varying physical properties and tactile feedback to the player. Furthermore, the well defined...... note onsets and short interaction times between player and instrument do not allow for much adjustment once a stroke is initiated. The paper surveys research that shows a close relationship between movement and sound production, and how playing conditions such as tempo and the rebound after impact...
Zich, Catharina; Debener, Stefan; De Vos, Maarten; Frerichs, Stella; Maurer, Stefanie; Kranczioch, Cornelia
The mental practice of movements has been suggested as a promising add-on therapy to facilitate motor recovery after stroke. In the case of mentally practised movements, electroencephalogram (EEG) can be utilized to provide feedback about an otherwise covert act. The main target group for such an intervention are elderly patients, though research so far is largely focused on young populations (study therefore aimed to examine the influence of age on the neural correlates of covert movements (CMs) in a real-time EEG neurofeedback framework. CM-induced event-related desynchronization (ERD) was studied in young (mean age: 23.6 years) and elderly (mean age: 62.7 years) healthy adults. Participants performed covert and overt hand movements. CMs were based on kinesthetic motor imagery (MI) or quasi-movements (QM). Based on previous studies investigating QM in the mu frequency range (8-13Hz) QM were expected to result in more lateralized ERD% patterns and accordingly higher classification accuracies. Independent of CM strategy the elderly were characterized by a significantly reduced lateralization of ERD%, due to stronger ipsilateral ERD%, and in consequence, reduced classification accuracies. QM were generally perceived as more vivid, but no differences were evident between MI and QM in ERD% or classification accuracies. EEG feedback enhanced task-related activity independently of strategy and age. ERD% measures of overt and covert movements were strongly related in young adults, whereas in the elderly ERD% lateralization is dissociated. In summary, we did not find evidence in support of more pronounced ERD% lateralization patterns in QM. Our finding of a less lateralized activation pattern in the elderly is in accordance to previous research and with the idea that compensatory processes help to overcome neurodegenerative changes related to normal ageing. Importantly, it indicates that EEG neurofeedback studies should place more emphasis on the age of the potential end
Novack, Miriam A; Wakefield, Elizabeth M; Goldin-Meadow, Susan
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. Copyright © 2015 Elsevier B.V. All rights reserved.
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Mizuguchi, Nobuaki; Nakata, Hiroki; Kanosue, Kazuyuki
We utilized functional magnetic resonance imaging (fMRI) to evaluate the common brain region of motor imagery for the right and left upper and lower limbs. The subjects were instructed to repeatedly imagined extension and flexion of the right or left hands/ankles. Brain regions, which included the supplemental motor area (SMA), premotor cortex and parietal cortex, were activated during motor imagery. Conjunction analysis revealed that the left SMA and inferior frontal gyrus (IFG)/ventral premotor cortex (vPM) were commonly activated with motor imagery of the right hand, left hand, right foot, and left foot. This result suggests that these brain regions are activated during motor imagery in an effector independent manner. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Bilgin, Süleyman; Üser, Yavuz; Mercan, Muhammet
Today's technology has increased the interest in robotic systems andincrease the number of studies realized in this area. There are many studies on robotic systems inseveral fields to facilitate human life in the literature. In this study, arobot hand is designed to repeat finger movements depending upon flexiblesensors mounted on any wearable glove. In the literature, various sensors thatdetect the finger movement are used. The sensor that detects the angle of thefingers has b...
This thesis describes the measurement of brain-tissue functions in patients with movement disorders using positron emission tomography (PET). This scanning technique is a method for direct in vivo quantitation of the regional tissue content of positron emitting radionuclides in brain (or other organs) in an essentially non-invasive way. Ch. 2 outlines some general features of PET and describes the scanner which has been used for the studies in this thesis. Also the tracer methodology, as applied to data investigations of movement disorders, are discussed. Ch. 3 contains the results of the PET investigations which were performed in the study of movement disorders. The results are presented in the form of 12 papers. The main goals of these studies were the understanding of the pathophysiology of Parkinson's disease, Huntington's chorea, Steele-Richardson-Olzewski syndrome and special case reports. Ch. 4 summarizes the results of these publications and Ch. 5 concludes the main part of this thesis with a general discussion of movement disorders in relation to PET investigations. 697 refs.; 60 figs.; 31 tabs
Pedersen, Inge Nygaard
This chapter/article describes the historical development of the disciplin Psychodynamic Movement. The importance of this disciplin for self-experience and for training in developing a therapist identy for the music therapy students are emphasized. Prototypeexercises developed and simplified...
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....
Singer, Harvey S
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. Copyright © 2011 Elsevier B.V. All rights reserved.
Slimani, Maamer; Tod, David; Chaabene, Helmi; Miarka, Bianca; Chamari, Karim
The aims of the present review were to (i) provide a critical overview of the current literature on the effects of mental imagery on muscular strength in healthy participants and patients with immobilization of the upper extremity (i.e., hand) and anterior cruciate ligament (ACL), (ii) identify potential moderators and mediators of the “mental imagery-strength performance” relationship and (iii) determine the relative contribution of electromyography (EMG) and brain activities, neural and physiological adaptations in the mental imagery-strength performance relationship. This paper also discusses the theoretical and practical implications of the contemporary literature and suggests possible directions for future research. Overall, the results reveal that the combination of mental imagery and physical practice is more efficient than, or at least comparable to, physical execution with respect to strength performance. Imagery prevention intervention was also effective in reducing of strength loss after short-term muscle immobilization and ACL. The present review also indicates advantageous effects of internal imagery (range from 2.6 to 136.3%) for strength performance compared with external imagery (range from 4.8 to 23.2%). Typically, mental imagery with muscular activity was higher in active than passive muscles, and imagining “lifting a heavy object” resulted in more EMG activity compared with imagining “lifting a lighter object”. Thus, in samples of students, novices, or youth male and female athletes, internal mental imagery has a greater effect on muscle strength than external mental imagery does. Imagery ability, motivation, and self-efficacy have been shown to be the variables mediating the effect of mental imagery on strength performance. Finally, the greater effects of internal imagery than those of external imagery could be explained in terms of neural adaptations, stronger brain activation, higher muscle excitation, greater somatic and
Kilintari, Marina; Narayana, Shalini; Babajani-Feremi, Abbas; Rezaie, Roozbeh; Papanicolaou, Andrew C
The aim of this study was to identify brain regions involved in motor imagery and differentiate two alternative strategies in its implementation: imagining a motor act using kinesthetic or visual imagery. Fourteen adults were precisely instructed and trained on how to imagine themselves or others perform a movement sequence, with the aim of promoting kinesthetic and visual imagery, respectively, in the context of an fMRI experiment using block design. We found that neither modality of motor imagery elicits activation of the primary motor cortex and that each of the two modalities involves activation of the premotor area which is also activated during action execution and action observation conditions, as well as of the supplementary motor area. Interestingly, the visual and the posterior cingulate cortices show reduced BOLD signal during both imagery conditions. Our results indicate that the networks of regions activated in kinesthetic and visual imagery of motor sequences show a substantial, while not complete overlap, and that the two forms of motor imagery lead to a differential suppression of visual areas. Copyright © 2016 Elsevier B.V. All rights reserved.
properties specific to a given viewing angle can be depicted. In a set of perceptual control experiments, subjects scanned a visible display by (a) simply moving their eyes from one object to another, (b) sweeping an imaginary rifle sight over the display, or (c) tracking an imaginary point moving from one object to another. Eye-movement times varied linearly with 2-D interobject distance, as did time to scan with an imaginary rifle sight; time to tract a point varied independently with the 3-D and 2-D interobject distances. These results are compared with the analogous image scanning results to argue that imagery and perception share some representational structures but that mental image scanning is a process distinct from eye movements or eye-movement commands.
Aru, Jaan; Vasser, Madis; Zafra, Raul; Kulu, Sander
We investigated the "human octopus" phenomenon where subjects controlled virtual supernumerary hands through hand tracking technology and virtual reality. Four experiments were developed to study how subjects (n=10) operate with different number and behaviour of supernumerary hands. The behaviours involved inserting movement delays to the virtual hands and adjusting their movement scale or position. It was found that having more hands to operate with does not necessarily mean higher success r...
Invitto, Sara; Faggiano, Chiara; Sammarco, Silvia; De Luca, Valerio; De Paolis, Lucio T
In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user's hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects). After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP) components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning.
King, Andrea C; Smith, Lia J; Fridberg, Daniel J; Matthews, Alicia K; McNamara, Patrick J; Cao, Dingcai
Use and awareness of electronic nicotine delivery systems (ENDS; also known as electronic cigarettes or e-cigarettes) has increased rapidly in recent years, particularly among young adults. As use of ENDS resembles traditional smoking in both hand-to-mouth movements and inhalation and exhalation behaviors, we determined whether exposure to e-cigarette use via video exposure would act as a cue to elicit urge and desire for a combustible cigarette. Young adult smokers (mean age of 26.3 ± 4.1 years) were randomized to view a brief video montage of advertisements depicting either e-cigarette vaping (n = 38) or bottled water drinking (n = 40). Pre- and postcue exposure assessments were conducted in a controlled laboratory setting without other smoking or vaping cues present or behaviors allowed. Primary outcomes included change from pre-exposure baseline in smoking urge (Brief Questionnaire of Smoking Urges) and desire for a combustible and e-cigarette (visual analogue scales). Results showed that relative to exposure to the bottled water video, exposure to the ENDS video significantly increased smoking urge (p e-cigarette (p < .001). These findings provide preliminary evidence that passive exposure to video imagery of ENDS use may generalize as a condition cue and evoke urges for a combustible cigarette in young adult smokers. It remains to be determined whether such increases in urge and desire correspond to increases in actual smoking behavior. (c) 2016 APA, all rights reserved).
Full Text Available In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user’s hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects. After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning.
Zhang, Zhiwen; Duan, Feng; Zhou, Xin; Meng, Zixuan
Motor imagery (MI) electroencephalograph (EEG) signals are widely applied in brain-computer interface (BCI). However, classified MI states are limited, and their classification accuracy rates are low because of the characteristics of nonlinearity and nonstationarity. This study proposes a novel MI pattern recognition system that is based on complex algorithms for classifying MI EEG signals. In electrooculogram (EOG) artifact preprocessing, band-pass filtering is performed to obtain the frequency band of MI-related signals, and then, canonical correlation analysis (CCA) combined with wavelet threshold denoising (WTD) is used for EOG artifact preprocessing. We propose a regularized common spatial pattern (R-CSP) algorithm for EEG feature extraction by incorporating the principle of generic learning. A new classifier combining the K-nearest neighbor (KNN) and support vector machine (SVM) approaches is used to classify four anisomerous states, namely, imaginary movements with the left hand, right foot, and right shoulder and the resting state. The highest classification accuracy rate is 92.5%, and the average classification accuracy rate is 87%. The proposed complex algorithm identification method can significantly improve the identification rate of the minority samples and the overall classification performance. PMID:28874909
Ahn, Sangtae; Ahn, Minkyu; Cho, Hohyun; Jun, Sung Chan
Objective. We propose a new hybrid brain-computer interface (BCI) system that integrates two different EEG tasks: tactile selective attention (TSA) using a vibro-tactile stimulator on the left/right finger and motor imagery (MI) of left/right hand movement. Event-related desynchronization (ERD) from the MI task and steady-state somatosensory evoked potential (SSSEP) from the TSA task are retrieved and combined into two hybrid senses. Approach. One hybrid approach is to measure two tasks simultaneously; the features of each task are combined for testing. Another hybrid approach is to measure two tasks consecutively (TSA first and MI next) using only MI features. For comparison with the hybrid approaches, the TSA and MI tasks are measured independently. Main results. Using a total of 16 subject datasets, we analyzed the BCI classification performance for MI, TSA and two hybrid approaches in a comparative manner; we found that the consecutive hybrid approach outperformed the others, yielding about a 10% improvement in classification accuracy relative to MI alone. It is understood that TSA may play a crucial role as a prestimulus in that it helps to generate earlier ERD prior to MI and thus sustains ERD longer and to a stronger degree; this ERD may give more discriminative information than ERD in MI alone. Significance. Overall, our proposed consecutive hybrid approach is very promising for the development of advanced BCI systems.
Sharma, Nikhil; Jones, P S; Carpenter, T A; Baron, Jean-Claude
Motor Imagery (MI) is an attractive but intriguing means to access the motor network. There are marked inconsistencies in the functional imaging literature regarding the degree, extent and distribution of the primary motor cortex (BA 4) involvement during MI as compared to Executed Movement (EM), which may in part be related to the diverse role of BA 4 and its two subdivisions (i.e., 4a and 4p) in motor processes as well as to methodological issues. Here we used fMRI with monitoring of compliance to show that in healthy volunteers optimally screened for their ability to perform MI the contralateral BA 4 is involved during MI of a finger opposition sequence (2, 3, 4, 5; paced at 1 Hz), albeit less than during EM of the same sequence, and in a location sparing the hand area. Furthermore, both 4a and 4p subdivisions were found to be involved in MI, but the relative involvement of BA 4p appeared more robust and closer to that seen with EM. We suggest that during MI the role of BA 4 and its subdivisions may be non-executive, perhaps related to spatial encoding, though clearly further studies are needed. Finally, we report a similar hemispheric activation balance within BA 4 with both tasks, which extends the commonalities between EM and MI.
Liu, Rensong; Zhang, Zhiwen; Duan, Feng; Zhou, Xin; Meng, Zixuan
Motor imagery (MI) electroencephalograph (EEG) signals are widely applied in brain-computer interface (BCI). However, classified MI states are limited, and their classification accuracy rates are low because of the characteristics of nonlinearity and nonstationarity. This study proposes a novel MI pattern recognition system that is based on complex algorithms for classifying MI EEG signals. In electrooculogram (EOG) artifact preprocessing, band-pass filtering is performed to obtain the frequency band of MI-related signals, and then, canonical correlation analysis (CCA) combined with wavelet threshold denoising (WTD) is used for EOG artifact preprocessing. We propose a regularized common spatial pattern (R-CSP) algorithm for EEG feature extraction by incorporating the principle of generic learning. A new classifier combining the K -nearest neighbor (KNN) and support vector machine (SVM) approaches is used to classify four anisomerous states, namely, imaginary movements with the left hand, right foot, and right shoulder and the resting state. The highest classification accuracy rate is 92.5%, and the average classification accuracy rate is 87%. The proposed complex algorithm identification method can significantly improve the identification rate of the minority samples and the overall classification performance.
Invitto, Sara; Faggiano, Chiara; Sammarco, Silvia; De Luca, Valerio; De Paolis, Lucio T.
In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user’s hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects). After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP) components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning. PMID:26999151
van Rompay, T.J.L.; Fransen, M.L.; Borgelink, B.G.D.
Inspired by the increasing importance of packaging design for product and brand management, this study tests effects of movement visuals and location of imagery on sensorial product impressions. Participants were exposed to a packaging variant for a fictitious brand of washing powder. Subsequently,
van Rompay, Thomas Johannes Lucas; Fransen, M.L.; Borgelink, Bianca G.D.
Inspired by the increasing importance of packaging design for product and brand management, this study tests effects of movement visuals and location of imagery on sensorial product impressions. Participants were exposed to a packaging variant for a fictitious brand of washing powder. Subsequently,
Briggs, G.F. Hole, G.J. & Land, M.F.
The effects of imagery-induced distraction on hazard perception and eye movements were investigated in 2 simulated driving experiments. Experiment 1: sixty participants viewed and responded to 2 driving films containing hazards. Group 1 completed the task without distraction; group 2 completed a
Fai Chen Chen
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.
... All Topics A-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 Osteoarthritis Email to a friend * required fields From * ...
... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is ... Hand Therapist? Media Find a Hand Surgeon Home Anatomy ... hands, being composed of many types of tissue, including blood vessels, nerves, skin and skin-related tissues, bones, and muscles/tendons/ligaments, may show changes that reflect a ...
Hollins, M; Favorov, O
The existence of a tactile movement aftereffect was established in a series of experiments on the palmar surface of the hand and fingers of psychophysical observers. During adaptation, observers cupped their hand around a moving drum for up to 3 min; following this period of stimulation, they typically reported an aftereffect consisting of movement sensations located on and deep to the skin, and lasting for up to 1 min. Preliminary experiments comparing a number of stimulus materials mounted on the drum demonstrated that a surface approximating a low-spatial-frequency square wave, with a smooth microtexture, was especially effective at inducing the aftereffect; this adapting stimulus was therefore used throughout the two main experiments. In Experiment 1, the vividness of the aftereffect produced by 2 min of adaptation was determined under three test conditions: with the hand (1) remaining on the now stationary drum; (2) in contact with a soft, textured surface; or (3) suspended in air. Subjects' free magnitude estimates of the peak vividness of the aftereffect were not significantly different across conditions; each subject experienced the aftereffect at least once under each condition. Thus the tactile movement aftereffect does not seem to depend critically on the ponditions of stimulation that obtain while it is being experienced. In Experiment 2, the vividness and duration of the aftereffect were measured as a function of the duration of the adapting stimulus. Both measures increased steadily over the range of durations explored (30-180 sec). In its dependence on adapting duration, the aftereffect resembles the waterfall illusion in vision. An explanation for the tactile movement aftereffect is proposed, based on the model of cortical dynamics of Whitsel et al. (1989, 1991). With assumed modest variation of one parameter across individuals, this application of the model is able to account both for the data of the majority of subjects, who experienced the
Laursen, Hilmar Dyrborg; Nielsen, Birgitte Lund
Som del af det internationale EU finansierede projekt Hand in Hand, der fokuserer på de såkaldte SEI-kompetencer (Social, Emotional, Intercultural), er dansk policy i relation til elevernes sociale, emotionelle og interkulturelle læring kortlagt i denne rapport. Der refereres bl.a. til "elevernes...
Farm Service Agency, Department of Agriculture — The AgSat Imagery Collection Footprints map shows the imagery footprints which have been collected under the USDA satellite blanket purchase agreement. Click on a...
D. Pecher (Diane); S. van Dantzig (Saskia); H.N.J. Schifferstien (Hendrik)
textabstractAccording to theories of grounded cognition, conceptual representation and perception share processing mechanisms. We investigated whether this overlap is due to conscious perceptual imagery. Participants filled out questionnaires to assess the vividness of their imagery (Questionnaire
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
Jurjen van der Helden
Full Text Available Mankind is unique in her ability for observational learning, i.e. the transmission of acquired knowledge and behavioral repertoire through observation of others' actions. In the present study we used electrophysiological measures to investigate brain mechanisms of observational learning. Analysis investigated the possible functional coupling between occipital (alpha and motor (mu rhythms operating in the 10 Hz frequency range for translating "seeing" into "doing". Subjects observed movement sequences consisting of six consecutive left or right hand button presses directed at one of two target-buttons for subsequent imitation. Each movement sequence was presented four times, intervened by short pause intervals for sequence rehearsal. During a control task subjects observed the same movement sequences without a requirement for subsequent reproduction. Although both alpha and mu rhythms desynchronized during the imitation task relative to the control task, modulations in alpha and mu power were found to be largely independent from each other over time, arguing against a functional coupling of alpha and mu generators during observational learning. This independence was furthermore reflected in the absence of coherence between occipital and motor electrodes overlaying alpha and mu generators. Instead, coherence analysis revealed a pair of symmetric fronto-parietal networks, one over the left and one over the right hemisphere, reflecting stronger coherence during observation of movements than during pauses. Individual differences in fronto-parietal coherence were furthermore found to predict imitation accuracy. The properties of these networks, i.e. their fronto-parietal distribution, their ipsilateral organization and their sensitivity to the observation of movements, match closely with the known properties of the mirror neuron system (MNS as studied in the macaque brain. These results indicate a functional dissociation between higher order areas for
Reina, G Anthony; Schwartz, Andrew B
Previous paradigms have used reaching movements to study coupling of eye-hand kinematics. In the present study, we investigated eye-hand kinematics as curved trajectories were drawn at normal speeds. Eye and hand movements were tracked as a monkey traced ellipses and circles with the hand in free space while viewing the hand's position on a computer monitor. The results demonstrate that the movement of the hand was smooth and obeyed the 2/3 power law. Eye position, however, was restricted to 2-3 clusters along the hand's trajectory and fixed approximately 80% of the time in one of these clusters. The eye remained stationary as the hand moved away from the fixation for up to 200 ms and saccaded ahead of the hand position to the next fixation along the trajectory. The movement from one fixation cluster to another consistently occurred just after the tangential hand velocity had reached a local minimum, but before the next segment of the hand's trajectory began. The next fixation point was close to an area of high curvature along the hand's trajectory even though the hand had not reached that point along the path. A visuo-motor illusion of hand movement demonstrated that the eye movement was influenced by hand movement and not simply by visual input. During the task, neural activity of pre-motor cortex (area F4) was recorded using extracellular electrodes and used to construct a population vector of the hand's trajectory. The results suggest that the saccade onset is correlated in time with maximum curvature in the population vector trajectory for the hand movement. We hypothesize that eye and arm movements may have common, or shared, information in forming their motor plans.
Full Text Available Background: Alien hand syndrome (AHS is a disorder of involuntary, yet purposeful, hand movements that may be accompanied by agnosia, aphasia, weakness, or sensory loss. We herein review the most reported cases, current understanding of the pathophysiology, and treatments.Methods: We performed a PubMed search in July of 2014 using the phrases “alien hand syndrome,” “alien hand syndrome pathophysiology,” “alien hand syndrome treatment,” and “anarchic hand syndrome.” The search yielded 141 papers (reviews, case reports, case series, and clinical studies, of which we reviewed 109. Non‐English reports without English abstracts were excluded.Results: Accumulating evidence indicates that there are three AHS variants: frontal, callosal, and posterior. Patients may demonstrate symptoms of multiple types; there is a lack of correlation between phenomenology and neuroimaging findings. Most pathologic and functional imaging studies suggest network disruption causing loss of inhibition as the likely cause. Successful interventions include botulinum toxin injections, clonazepam, visuospatial coaching techniques, distracting the affected hand, and cognitive behavioral therapy.Discussion: The available literature suggests that overlap between AHS subtypes is common. The evidence for effective treatments remains anecdotal, and, given the rarity of AHS, the possibility of performing randomized, placebo‐controlled trials seems unlikely. As with many other interventions for movement disorders, identifying the specific functional impairments caused by AHS may provide the best guidance towards individualized supportive care.
Linares Scarcerieau, Carlo Andrei
Agreement and movement go hand in hand in a number of constructions across languages, and this correlation has played an important role in syntactic theory. The current standard approach to this "movement-agreement connection" is the Agree+EPP model, whose EPP component has often been questioned on conceptual grounds. The goal of this…
Tolston, Michael T; Shockley, Kevin; Riley, Michael A; Richardson, Michael J
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.
Yao, Lin; Meng, Jianjun; Zhang, Dingguo; Sheng, Xinjun; Zhu, Xiangyang
A hybrid modality brain-computer interface (BCI) is proposed in this paper, which combines motor imagery with selective sensation to enhance the discrimination between left and right mental tasks, e.g., the classification between left/ right stimulation sensation and right/ left motor imagery. In this paradigm, wearable vibrotactile rings are used to stimulate both the skin on both wrists. Subjects are required to perform the mental tasks according to the randomly presented cues (i.e., left hand motor imagery, right hand motor imagery, left stimulation sensation or right stimulation sensation). Two-way ANOVA statistical analysis showed a significant group effect (F (2,20) = 7.17, p = 0.0045), and the Benferroni-corrected multiple comparison test (with α = 0.05) showed that the hybrid modality group is 11.13% higher on average than the motor imagery group, and 10.45% higher than the selective sensation group. The hybrid modality experiment exhibits potentially wider spread usage within ten subjects crossed 70% accuracy, followed by four subjects in motor imagery and five subjects in selective sensation. Six subjects showed statistically significant improvement ( Benferroni-corrected) in hybrid modality in comparison with both motor imagery and selective sensation. Furthermore, among subjects having difficulties in both motor imagery and selective sensation, the hybrid modality improves their performance to 90% accuracy. The proposed hybrid modality BCI has demonstrated clear benefits for those poorly performing BCI users. Not only does the requirement of motor and sensory anticipation in this hybrid modality provide basic function of BCI for communication and control, it also has the potential for enhancing the rehabilitation during motor recovery.
The purpose of this presentation was to inform the ISS International Partners of the new NASA Agency Video, Audio and Imagery Library (AVAIL) website. AVAIL is a new resource for the public to search for and download NASA-related imagery, and is not intended to replace the current process by which the International Partners receive their Space Station imagery products.
Clark, Robert L.
Thirty-two students at the University of Oregon were tested to determine the effects of media on mental imagery and memory. The model incorporates a dual coding hypothesis, and five single and multiple channel treatments were used. (Author/JEG)
Davison, Kevin G.
This article suggests utilizing dialectical imagery, as understood by German social philosopher Walter Benjamin, as an additional qualitative data analysis strategy for research into the postmodern condition. The use of images mined from research data may offer epistemological transformative possibilities that will assist in the demystification of…
Selected verses from Abdullah Yusuf Ali's English language translation of the meaning of the Quran have been used as a literary text to teach both descriptive and figurative imagery (including similes, metaphors and symbols) to students at the undergraduate level in an Islamic institution. The technique--Illustrating and Designing for teaching…
Peppler, Kylie; Bender, Sophia
The maker movement consists of a growing culture of hands-on making, creating, designing, and innovating. A hallmark of the maker movement is its do-it-yourself (or do-it-with-others) mindset that brings individuals together around a range of activities, both high- and low-tech, all involving some form of creation or repair. The movement's…
Thompson, Sarah; Nicholson, Lindsey; Klug, Christoph; Rieg, Lorenzo; Sailer, Rudolf; Bucher, Tilman; Brauchle, Jörg
In the high, steep terrain of the Khumbu Himal, Nepal, snow avalanches play an important role in glacier mass balance, and rockfall supplies much of the rock material that forms the extensive debris covers on glaciers in the region. Information on the frequency and size of gravitational mass movements is helpful for understanding current and future glacier behaviour but currently lacking. In this study we use a combination of high resolution Pleiades optical satellite imagery in conjunction with airborne HDR imagery of slopes in deep shadow or overexposed snow slopes, provided by the German Aerospace Center (DLR) MACS system (see Brauchle et al., MM3.2/GI2.12/GMPV6.4/HS11.13/NH8.9/SSS12.24), to undertake a qualitative observational study of the gravitational processes evident in these sets of imagery. We classify the features found and discuss their likely frequency in the context of previously published research findings. Terrain analysis based upon digital terrain models derived from the same Pleiades imagery is used to investigate the slope angle, degree of confinement, curvature and aspect of observed avalanche and rock fall tracks. This work presents a first overview of the types of gravitational slides affecting glaciers of the Khumbu Himal. Subsequent research efforts will focus on attempting to quantify volumes of mass movement using repeat satellite imagery.
Chen, Ya-Ting; Tsou, Kuo-Su; Chen, Hao-Ling; Wong, Ching-Ching; Fan, Yang-Teng; Wu, Chien-Te
Whether action representation in individuals with autism spectrum disorder (ASD) is deficient remains controversial, as previous studies of action observation or imitation report conflicting results. Here we investigated the characteristics of action representation in adolescents with ASD through motor imagery (MI) using a hand rotation and an…
Full Text Available ... to promote or encourage adherence to CDC hand hygiene recommendations. It is a component of the Clean ... aims to address myths and misperceptions about hand hygiene and empower patients to play a role in ...
Full Text Available ... intended to promote or encourage adherence to CDC hand hygiene recommendations. It is a component of the Clean ... also aims to address myths and misperceptions about hand hygiene and empower patients to play a role in ...
... intended to promote or encourage adherence to CDC hand hygiene recommendations. It is a component of the Clean ... also aims to address myths and misperceptions about hand hygiene and empower patients to play a role in ...
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Kwak, M.; Frens, J.W.
This one-day studio revolves around the exploration of expressive movement qualities in shape-change by means of physical sketching and prototyping. It is a hands-on studio where participants first explore expressive movement qualities and interaction scenarios with a generic shape-changing platform
Yazaji, Eskandar Alex
Hand hygiene is one of the major players in preventing healthcare associated infections. However, healthcare workers compliance with hand hygiene continues to be a challenge. This article will address strategies to help improving hand hygiene compliance. Keywords: hand hygiene; healthcare associated infections; multidisciplinary program; system change; accountability; education; feedback(Published: 18 July 2011)Citation: Journal of Community Hospital Internal Medicine Perspectives 2011, 1: 72...
Full Text Available Motor imagery is a mental representation of an action without its physical execution. Recently, the simultaneous movement of the body has been added to the mental simulation. This refers to dynamic motor imagery (dMI. This study was aimed at analyzing the temporal features for static and dMI in different locomotor conditions (natural walking, NW, light running, LR, lateral walking, LW, backward walking, BW, and whether these performances were more related to all the given conditions or present only in walking. We have been also evaluated the steps performed in the dMI in comparison with the ones performed by real locomotion. Twenty healthy participants (29.3 ± 5.1 y. old were asked to move towards a visualized target located at 10mt. In dMI, no significant temporal differences respect the actual locomotion were found for all the given tasks (NW: p=0.058, LR: p=0.636, BW: p=0.096; LW: p=0,487. Significant temporal differences between static imagery and actual movements were found for LR (p<0.001 and LW (p<0.001, due to an underestimation of time needed to achieve the target in imagined locomotion. Significant differences in terms of number of steps among tasks were found for LW (p<0.001 and BW (p=0.036, whereas neither in NW (p=0.124 nor LR (p=0.391 between dMI and real locomotion.Our results confirmed that motor imagery is a task-dependent process, with walking being temporally closer than other locomotor conditions. Moreover, the time records of dynamic motor imagery are nearer to the ones of actual locomotion respect than the ones of static motor imagery. Keywords: Walking, dynamic motor imagery, human locomotion, chronometry.
Amemiya, Kaoru; Naito, Eiichi
It is generally believed that the human right cerebral hemisphere plays a dominant role in corporeal awareness, which is highly associated with conscious experience of the physical self. Prompted by our previous findings, we examined whether the right frontoparietal activations often observed when people experience kinesthetic illusory limb movement are supported by a large-scale brain network connected by a specific branch of the superior longitudinal fasciculus fiber tracts (SLF I, II, and III). We scanned brain activity with functional magnetic resonance imaging (MRI) while nineteen blindfolded healthy volunteers experienced illusory movement of the right stationary hand elicited by tendon vibration, which was replicated after the scanning. We also scanned brain activity when they executed and imagined right hand movement, and identified the active brain regions during illusion, execution, and imagery in relation to the SLF fiber tracts. We found that illusion predominantly activated the right inferior frontoparietal regions connected by SLF III, which were not substantially recruited during execution and imagery. Among these regions, activities in the right inferior parietal cortices and inferior frontal cortices showed right-side dominance and correlated well with the amount of illusion (kinesthetic illusory awareness) experienced by the participants. The results illustrated the predominant involvement of the right inferior frontoparietal network connected by SLF III when people recognize postural changes of their limb. We assume that the network bears a series of functions, specifically, monitoring the current status of the musculoskeletal system, and building-up and updating our postural model (body schema), which could be a basis for the conscious experience of the physical self. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Goldberg, Judith L
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. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.
Salisbury, Curt Michael; Dullea, Kevin J.
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.
Holmes, Emily A; Blackwell, Simon E; Burnett Heyes, Stephanie; Renner, Fritz; Raes, Filip
Mental imagery is an experience like perception in the absence of a percept. It is a ubiquitous feature of human cognition, yet it has been relatively neglected in the etiology, maintenance, and treatment of depression. Imagery abnormalities in depression include an excess of intrusive negative mental imagery; impoverished positive imagery; bias for observer perspective imagery; and overgeneral memory, in which specific imagery is lacking. We consider the contribution of imagery dysfunctions to depressive psychopathology and implications for cognitive behavioral interventions. Treatment advances capitalizing on the representational format of imagery (as opposed to its content) are reviewed, including imagery rescripting, positive imagery generation, and memory specificity training. Consideration of mental imagery can contribute to clinical assessment and imagery-focused psychological therapeutic techniques and promote investigation of underlying mechanisms for treatment innovation. Research into mental imagery in depression is at an early stage. Work that bridges clinical psychology and neuroscience in the investigation of imagery-related mechanisms is recommended.
Keller, Martin; Taube, Wolfgang; Lauber, Benedikt
Motor imagery and actual movements share overlapping activation of brain areas but little is known about task-specific activation of distinct motor pathways during mental simulation of movements. For real contractions, it was demonstrated that the slow(er) motor pathways are activated differently in ballistic compared to tonic contractions but it is unknown if this also holds true for imagined contractions. The aim of the present study was to assess the activity of fast and slow(er) motor pathways during mentally simulated movements of ballistic and tonic contractions. H-reflexes were conditioned with transcranial magnetic stimulation at different interstimulus intervals to assess the excitability of fast and slow(er) motor pathways during a) the execution of tonic and ballistic contractions, b) motor imagery of these contraction types, and c) at rest. In contrast to the fast motor pathways, the slow(er) pathways displayed a task-specific activation: for imagined ballistic as well as real ballistic contractions, the activation was reduced compared to rest whereas enhanced activation was found for imagined tonic and real tonic contractions. This study provides evidence that the excitability of fast and slow(er) motor pathways during motor imagery resembles the activation pattern observed during real contractions. The findings indicate that motor imagery results in task- and pathway-specific subliminal activation of distinct subsets of neurons in the primary motor cortex. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.
Faber, T.W.; van Elk, M.; Jonas, K.J.
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
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.
Ron-Angevin, Ricardo; Velasco-Álvarez, Francisco; Fernández-Rodríguez, Álvaro; Díaz-Estrella, Antonio; Blanca-Mena, María José; Vizcaíno-Martín, Francisco Javier
Certain diseases affect brain areas that control the movements of the patients' body, thereby limiting their autonomy and communication capacity. Research in the field of Brain-Computer Interfaces aims to provide patients with an alternative communication channel not based on muscular activity, but on the processing of brain signals. Through these systems, subjects can control external devices such as spellers to communicate, robotic prostheses to restore limb movements, or domotic systems. The present work focus on the non-muscular control of a robotic wheelchair. A proposal to control a wheelchair through a Brain-Computer Interface based on the discrimination of only two mental tasks is presented in this study. The wheelchair displacement is performed with discrete movements. The control signals used are sensorimotor rhythms modulated through a right-hand motor imagery task or mental idle state. The peculiarity of the control system is that it is based on a serial auditory interface that provides the user with four navigation commands. The use of two mental tasks to select commands may facilitate control and reduce error rates compared to other endogenous control systems for wheelchairs. Seventeen subjects initially participated in the study; nine of them completed the three sessions of the proposed protocol. After the first calibration session, seven subjects were discarded due to a low control of their electroencephalographic signals; nine out of ten subjects controlled a virtual wheelchair during the second session; these same nine subjects achieved a medium accuracy level above 0.83 on the real wheelchair control session. The results suggest that more extensive training with the proposed control system can be an effective and safe option that will allow the displacement of a wheelchair in a controlled environment for potential users suffering from some types of motor neuron diseases.
Fatone, Gina A.; Clayton, Martin; Leante, Laura; Rahaim, Matt
Musical action is also physical action. This is obvious in cases such as moving the arm to direct a bow across a cello string, turning the hand to control the vibrations of a drumhead or inclining the cartilages of the larynx to raise the pitch of a sung note. In addition to producing sound, however, physical motion can also serve as a means of conceiving and conveying music: motion is linked in turn to visual imagery and other aspects of the conceptualization of music. Auditor...
Winlove, Crawford I P; Milton, Fraser; Ranson, Jake; Fulford, Jon; MacKisack, Matthew; Macpherson, Fiona; Zeman, Adam
Visual imagery is a form of sensory imagination, involving subjective experiences typically described as similar to perception, but which occur in the absence of corresponding external stimuli. We used the Activation Likelihood Estimation algorithm (ALE) to identify regions consistently activated by visual imagery across 40 neuroimaging studies, the first such meta-analysis. We also employed a recently developed multi-modal parcellation of the human brain to attribute stereotactic co-ordinates to one of 180 anatomical regions, the first time this approach has been combined with the ALE algorithm. We identified a total 634 foci, based on measurements from 464 participants. Our overall comparison identified activation in the superior parietal lobule, particularly in the left hemisphere, consistent with the proposed 'top-down' role for this brain region in imagery. Inferior premotor areas and the inferior frontal sulcus were reliably activated, a finding consistent with the prominent semantic demands made by many visual imagery tasks. We observed bilateral activation in several areas associated with the integration of eye movements and visual information, including the supplementary and cingulate eye fields (SCEFs) and the frontal eye fields (FEFs), suggesting that enactive processes are important in visual imagery. V1 was typically activated during visual imagery, even when participants have their eyes closed, consistent with influential depictive theories of visual imagery. Temporal lobe activation was restricted to area PH and regions of the fusiform gyrus, adjacent to the fusiform face complex (FFC). These results provide a secure foundation for future work to characterise in greater detail the functional contributions of specific areas to visual imagery. Copyright © 2017. Published by Elsevier Ltd.
Matheson, Eloise; Brooker, Graham
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
Yocky, David A.; Wahl, Daniel E.; Jakowatz, Charles V,
While typical SAR imaging employs a co-located (monostatic) RADAR transmitter and receiver, bistatic SAR imaging separates the transmitter and receiver locations. The transmitter and receiver geometry determines if the scattered signal is back scatter, forward scatter, or side scatter. The monostatic SAR image is backscatter. Therefore, depending on the transmitter/receiver collection geometry, the captured imagery may be quite different that that sensed at the monostatic SAR. This document presents imagery and image products formed from captured signals during the validation stage of the bistatic SAR research. Image quality and image characteristics are discussed first. Then image products such as two-color multi-view (2CMV) and coherent change detection (CCD) are presented.
Galbraith, Amy E. [Univ. of Arizona, Tucson, AZ (United States)
This dissertation studies the feasibility of enhancing the spatial resolution of multi-look remotely-sensed imagery using an iterative resolution enhancement algorithm known as Projection Onto Convex Sets (POCS). A multi-angle satellite image modeling tool is implemented, and simulated multi-look imagery is formed to test the resolution enhancement algorithm. Experiments are done to determine the optimal con guration and number of multi-angle low-resolution images needed for a quantitative improvement in the spatial resolution of the high-resolution estimate. The important topic of aliasing is examined in the context of the POCS resolution enhancement algorithm performance. In addition, the extension of the method to multispectral sensor images is discussed and an example is shown using multispectral confocal fluorescence imaging microscope data. Finally, the remote sensing issues of atmospheric path radiance and directional reflectance variations are explored to determine their effect on the resolution enhancement performance.
Nielsen, Kathleen; Henderson, Sheila; Barnett, Anna L.; Abbott, Robert D.; Berninger, Virginia
Movement, which draws on motor skills and executive functions for managing them, plays an important role in literacy learning (e.g., movement of mouth during oral reading and movement of hand and fingers during writing); but relatively little research has focused on movement skills in students with specific learning disabilities as the current…
Matthews, Natasha L; Collins, Kathleen P; Thakkar, Katharine N; Park, Sohee
The ability to form mental images that reconstruct former perceptual experiences is closely related to working memory (WM) ability. However, whereas WM deficits are established as a core feature of schizophrenia, an independent body of work suggests that mental imagery ability is enhanced in the disorder. Across two experiments we investigated mental imagery in schizophrenia and its relationship with WM. In Experiment 1, individuals with schizophrenia (SZ: n=15) and matched controls (CO: n=14) completed a mental imagery generation and inspection task and a spatial delayed-response WM task. In Experiment 2, SZ (n=16) and CO (n=16) completed a novel version of the mental imagery task modified to increase WM maintenance demand. In Experiment 1, SZ demonstrated enhanced mental imagery performance, as evidenced by faster response times relative to CO, with preserved accuracy. However, enhanced mental imagery in SZ was accompanied by impaired WM as assessed by the delayed-response task. In Experiment 2, when WM maintenance load was increased, SZ no longer showed superior imagery performance. We found evidence for enhanced imagery manipulation in SZ despite their WM maintenance deficit. However, this imagery enhancement was abolished when WM maintenance demands were increased. This profile of enhanced imagery manipulation but impaired maintenance could be used to implement novel remediation strategies in the disorder.
Full Text Available Visible/Infrared Imaging Radiometer Suite (VIIRS Imagery from the Suomi National Polar-orbiting Partnership (S-NPP satellite is the finest spatial resolution (375 m multi-spectral imagery of any operational meteorological satellite to date. The Imagery environmental data record (EDR has been designated as a Key Performance Parameter (KPP for VIIRS, meaning that its performance is vital to the success of a series of Joint Polar Satellite System (JPSS satellites that will carry this instrument. Because VIIRS covers the high-latitude and Polar Regions especially well via overlapping swaths from adjacent orbits, the Alaska theatre in particular benefits from VIIRS more than lower-latitude regions. While there are no requirements that specifically address the quality of the EDR Imagery aside from the VIIRS SDR performance requirements, the value of VIIRS Imagery to operational users is an important consideration in the Cal/Val process. As such, engaging a wide diversity of users constitutes a vital part of the Imagery validation strategy. The best possible image quality is of utmost importance. This paper summarizes the Imagery Cal/Val Team’s quality assessment in this context. Since users are a vital component to the validation of VIIRS Imagery, specific examples of VIIRS imagery applied to operational needs are presented as an integral part of the post-checkout Imagery validation.
Miller, H.; Sexton, N.; Koontz, L.
Landsat satellites provide high-quality, multi-spectral imagery of the surface of the Earth. These moderate-resolution, remotely sensed images are not just pictures, but contain many layers of data collected at different points along the visible and invisible light spectrum. These data can be manipulated to reveal what the Earth’s surface looks like, including what types of vegetation are present or how a natural disaster has impacted an area (Fig. 1).
Jarus, T; Poremba, R
The purpose of this study was to investigate hand function evaluations. Factor analysis with varimax rotation was used to assess the fundamental characteristics of the items included in the Jebsen Hand Function Test and the Smith Hand Function Evaluation. The study sample consisted of 144 subjects without disabilities and 22 subjects with Colles fracture. Results suggest a four factor solution: Factor I--pinch movement; Factor II--grasp; Factor III--target accuracy; and Factor IV--activities of daily living. These categories differentiated the subjects without Colles fracture from the subjects with Colles fracture. A hand function evaluation consisting of these four factors would be useful. Such an evaluation that can be used for current clinical purposes is provided.
Thomsen, J. F.; Mikkelsen, S.; Andersen, JH
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...... (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......, controlling for potential personal and psychosocial confounders. All participants were re-examined three times during a follow-up period of three years. RESULTS: Force but not repetition and position was related to hand-wrist pain and possible tendonitis in the baseline analyses showing an exposure...
Yang, Fang; Feldman, Anatol G
It is known that hand transport and grasping are functionally different but spatially coordinated components of reach-to-grasp (RTG) movements. As an extension of this notion, we suggested that body segments involved in RTG movements are controlled as a coherent ensemble by a global minimization process associated with the necessity for the hand to reach the motor goal. Different RTG components emerge following this process without pre-programming. Specifically, the minimization process may result from the tendency of neuromuscular elements to diminish the spatial gap between the actual arm-hand configuration and its virtual (referent) configuration specified by the brain. The referent configuration is specified depending on the object shape, localization, and orientation. Since the minimization process is gradual, it can be interrupted and resumed following mechanical perturbations, at any phase during RTG movements, including hand closure. To test this prediction of the minimization hypothesis, we asked subjects to reach and grasp a cube placed within the reach of the arm. Vision was prevented during movement until the hand returned to its initial position. As predicted, by arresting wrist motion at different points of hand transport in randomly selected trials, it was possible to halt changes in hand aperture at any phase, not only during hand opening but also during hand closure. Aperture changes resumed soon after the wrist was released. Another test of the minimization hypothesis was made in RTG movements to an object placed beyond the reach of the arm. It has previously been shown (Rossi et al. in J Physiol 538:659-671, 2002) that in such movements, the trunk motion begins to contribute to hand transport only after a critical phase when the shifts in the referent arm configuration have finished (at about the time when hand velocity is maximal). The minimization rule suggests that when the virtual contribution of the arm to hand transport is completed
Koeneman, E J; Schultz, R S; Wolf, S L; Herring, D E; Koeneman, J B
Intensive repetitive therapy improves function and quality of life for stroke patients. Intense therapies to overcome upper extremity impairment are beneficial, however, they are expensive because, in part, they rely on individualized interaction between the patient and rehabilitation specialist. The development of a pneumatic muscle driven hand therapy device, the Mentortrade mark, reinforces the need for volitional activation of joint movement while concurrently offering knowledge of results about range of motion, muscle activity or resistance to movement. The device is well tolerated and has received favorable comments from stroke survivors, their caregivers, and therapists.
Michida, Nanae; Hayashi, Mitsuo; Hori, Tadao
The purpose of this study was to examine the influence of hypnagogic imagery on the information processes of external tone stimuli during the sleep onset period with the use of event-related potentials. Event-related potentials to tone stimuli were compared between conditions with and without the experience of hypnagogic imagery. To control the arousal level when the tone was presented, a certain criterion named the electroencephalogram stage was used. Stimuli were presented at electroencephalogram stage 4, which was characterized by the appearance of a vertex sharp wave. Data were collected in the sleep laboratory at Hiroshima University. Eleven healthy university and graduate school students participated in the study. N/A. Experiments were performed at night. Reaction times to tone stimuli were measured, and only trials with shorter reaction times than 5000 milliseconds were analyzed. Electroencephalograms were recorded from Fz, Cz, Pz, Oz, T5 and T6. There were no differences in reaction times and electroencephalogram spectra between the conditions of with and without hypnagogic imagery. These results indicated that the arousal levels were not different between the 2 conditions. On the other hand, the N550 amplitude of the event-related potentials in the imagery condition was lower than in the no-imagery condition. The decrease in the N550 amplitude in the imagery condition showed that experiences of hypnagogic imagery exert some influence on the information processes of external tone stimuli. It is possible that the processing of hypnagogic imagery interferes with the processing of external stimuli, lowering the sensitivity to external stimuli.
Accidental self-inflicted knife injuries to digits are a common cause of tendon and nerve injury requiring hand surgery. There has been an apparent increase in avocado related hand injuries. Classically, the patients hold the avocado in their non-dominant hand while using a knife to cut\\/peel the fruit with their dominant hand. The mechanism of injury is usually a stabbing injury to the non-dominant hand as the knife slips past the stone, through the soft avocado fruit. Despite their apparent increased incidence, we could not find any cases in the literature which describe the “avocado hand”. We present a case of a 32-year-old woman who sustained a significant hand injury while preparing an avocado. She required exploration and repair of a digital nerve under regional anaesthesia and has since made a full recovery.
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.
Gabbard, Carl; Cordova, Alberto; Lee, Sunghan
We examined the question-is the intention of completing a simulated motor action the same as the intention used in processing overt actions? Participants used motor imagery to estimate distance reachability in two conditions: Imagery-Only (IO) and Imagery-Execution (IE). With IO (red target) only a verbal estimate using imagery was given. With IE (green target) participants knew that they would actually reach after giving a verbal estimate and be judged on accuracy. After measuring actual maximum reach, used for the comparison, imagery targets were randomly presented across peripersonal- (within reach) and extrapersonal (beyond reach) space. Results indicated no difference in overall accuracy by condition, however, there was a significant distinction by space; participants were more accurate in peripersonal space. Although more research is needed, these findings support an increasing body of evidence suggesting that the neurocognitive processes (in this case, intention) driving motor imagery and overt actions are similar.
Dietz, P E; Evans, B
The authors classified 1,760 heterosexual pornographic magazines according to the imagery of the cover photographs. Covers depicting only a woman posed alone predominated in 1970 but constituted only 10.7% of the covers in 1981. Bondage and domination imagery was the most prevalent nonormative imagery and was featured in 17.2% of the magazines. Smaller proportions of material were devoted to group sexual activity (9.8%), tranvestism and transsexualism (4.4%), and other nonnormative imagery. The authors suggest that pornographic imagery is an unobtrusive measure of the relative prevalence of those paraphilias associated with preferences for specific types of visual imagery and for which better data are lacking.
Diepgen, T L; Andersen, Klaus Ejner; Brandao, F M
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...... A classification system for hand eczema is proposed. Conclusions It is suggested that this classification be used in clinical work and in clinical trials....
Full Text Available The Very High Resolution (VHR satellite imageries such us Pleiades, WorldView-2, GeoEye-1 used for precise mapping purpose must be corrected from any distortion to achieve the expected accuracy. Orthorectification is performed to eliminate geometric errors of the VHR satellite imageries. Orthorectification requires main input data such as Digital Elevation Model (DEM and Ground Control Point (GCP. The VHR systematic-ortho imageries were generated using SRTM 30m DEM without using any GCP data. The accuracy value differences of VHR systematic-ortho imageries and VHR orthorectified imageries using GCP currently is not exactly defined. This study aimed to identified the accuracy comparison of VHR systematic-ortho imageries against orthorectified imageries using GCP. Orthorectified imageries using GCP created by using Rigorous model. Accuracy evaluation is calculated by using several independent check points.
Lum, Peter S; Godfrey, Sasha B; Brokaw, Elizabeth B; Holley, Rahsaan J; Nichols, Diane
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.
Homer, Sophie R; Deeprose, Catherine; Andrade, Jackie
This study sought to reconcile two lines of research. Previous studies have identified a prevalent and causal role of negative imagery in social phobia and public speaking anxiety; others have demonstrated that lateral eye movements during visualisation of imagery reduce its vividness, most likely by loading the visuospatial sketchpad of working memory. It was hypothesised that using eye movements to reduce the intensity of negative imagery associated with public speaking may reduce anxiety resulting from imagining a public speaking scenario compared to an auditory control task. Forty undergraduate students scoring high in anxiety on the Personal Report of Confidence as a Speaker scale took part. A semi-structured interview established an image that represented the participant's public speaking anxiety, which was then visualised during an eye movement task or a matched auditory task. Reactions to imagining a hypothetical but realistic public speaking scenario were measured. As hypothesised, representative imagery was established and reduced in vividness more effectively by the eye movement task than the auditory task. The public speaking scenario was then visualised less vividly and generated less anxiety when imagined after performing the eye movement task than after the auditory task. Self-report measures and a hypothetical scenario rather than actual public speaking were used. Replication is required in larger as well as clinical samples. Visuospatial working memory tasks may preferentially reduce anxiety associated with personal images of feared events, and thus provide cognitive resistance which reduces emotional reactions to imagined, and potentially real-life future stressful experiences. Copyright © 2015 Elsevier Ltd. All rights reserved.
Full Text Available Traditionally, philosophers have appealed to the phenomenological similarity between visual experience and visual imagery to support the hypothesis that there is significant overlap between the perceptual and imaginative domains. The current evidence, however, is inconclusive: while evidence from transcranial brain stimulation seems to support this conclusion, neurophysiological evidence from brain lesion studies (e.g., from patients with brain lesions resulting in a loss of mental imagery but not a corresponding loss of perception and vice versa indicates that there are functional and anatomical dissociations between mental imagery and perception. Assuming that the mental imagery and perception do not overlap, at least, to the extent traditionally assumed, then the question arises as to what exactly mental imagery is and whether it parallels perception by proceeding via several functionally distinct mechanisms. In this review, we argue that even though there may not be a shared mechanism underlying vision for perception and conscious imagery, there is an overlap between the mechanisms underlying vision for action and unconscious visual imagery. On the basis of these findings, we propose a modification of Kosslyn’s model of imagery that accommodates unconscious imagination and explore possible explanations of the quasi-pictorial phenomenology of conscious visual imagery in light of the fact that its underlying neural substrates and mechanisms typically are distinct from those of visual experience.
Many philosophers use findings about sensory substitution devices in the grand debate about how we should individuate the senses. The big question is this: Is "vision" assisted by (tactile) sensory substitution really vision? Or is it tactile perception? Or some sui generis novel form of perception? My claim is that sensory substitution assisted "vision" is neither vision nor tactile perception, because it is not perception at all. It is mental imagery: visual mental imagery triggered by tactile sensory stimulation. But it is a special form of mental imagery that is triggered by corresponding sensory stimulation in a different sense modality, which I call "multimodal mental imagery."
André Luiz Felix Rodacki
Full Text Available The aim of this study was to evaluate changes in motor imagery ability in response to a specific dart throwing training. Twelve subjects (17-22 years with no previous experience in dart throwing or imagery agreed to participate. Changes in imagery ability were assessed using the Sports Imagery Questionnaire before (pretreatment and after (post-treatment an imagery training program consisting of 10 sessions. Retention (RET was assessed 2 weeks after training. The program included mental exercises designed to develop vivid images, to control one’s own images, and to increase perception about performance. Comparison of the imagery training conditions (training alone, training accompanied, observing a colleague, and during assessment showed no differences between the pretreatment, post-treatment and RET evaluations. Although imagery ability did not respond to training, significant differences between imagery domains (visual, auditory, kinesthetic, and animic were found (p<0.05, except between the visual and animic domains (p=0.58. These differences might be related to subject’s domain preference subject during the imagery process and to the nature of the task in which the skill technique used seems to be a relevant aspect.
... Publications Patient Organizations International Parkinson and Movement Disorder Society National Institute of Mental Health (NIMH) See all related organizations Publications Order NINDS Publications Definition Psychogenic movement is an unwanted muscle movement such ...
Full Text Available ... 585 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 413,097 ... 089,212 views 4:50 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 26,032 views ...
Davidsen, Jacob; Christiansen, Ellen Tove
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 acce...
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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
Full Text Available ... 585 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 412,760 ... 536,963 views 1:46 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 25,574 views ...
Full Text Available ... today; no cure tomorrow - Duration: 3:10. World Health Organization 74,478 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 411,292 views 5:46 Hand Washing Technique - ...
Full Text Available ... 029 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 412,404 ... 081,511 views 4:50 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 25,194 views ...
Full Text Available ... today; no cure tomorrow - Duration: 3:10. World Health Organization 75,362 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 412,404 views 5:46 Hand Washing Technique - ...
Full Text Available ... 585 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 413,097 ... 086,746 views 4:50 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 25,802 views ...
Full Text Available ... 453 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 413,702 ... 28,656 views 3:40 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 26,480 views ...
Full Text Available ... 362 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 412,404 ... 219,427 views 1:27 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 25,194 views ...
Full Text Available ... 03. R Mayer 371,490 views 4:03 The psychological trick behind getting people to say yes - Duration: 8:06. PBS NewsHour 606,671 views 8:06 Should You Really Wash Your Hands? - Duration: 4:51. Gross Science 57,828 views 4:51 Healthcare Worker Hand ...
Full Text Available ... 585 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 413,097 ... 28,656 views 3:40 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 26,032 views ...
Chouk, Mickaël; Vidon, Claire; Deveza, Elise; Verhoeven, Frank; Pelletier, Fabien; Prati, Clément; Wendling, Daniel
Intravenous drug addiction is responsible for many complications, especially cutaneous and infectious. There is a syndrome, rarely observed in rheumatology, resulting in "puffy hands": the puffy hand syndrome. We report two cases of this condition from our rheumatologic consultation. Our two patients had intravenous drug addiction. They presented with an edema of the hands, bilateral, painless, no pitting, occurring in one of our patient during heroin intoxication, and in the other 2 years after stopping injections. In our two patients, additional investigations (biological, radiological, ultrasound) were unremarkable, which helped us, in the context, to put the diagnosis of puffy hand syndrome. The pathophysiology, still unclear, is based in part on a lymphatic toxicity of drugs and their excipients. There is no etiological treatment but elastic compression by night has improved edema of the hands in one of our patients. Copyright © 2016 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.
Federal Emergency Management Agency, Department of Homeland Security — This data set contains 1-meter resolution imagery derived from the 2005 National Agriculture Imagery Program (NAIP) statewide aerial imagery acquisition. Data have...
Thematic Mapping from Satellite Imagery: A Guidebook discusses methods in producing maps using satellite images. The book is comprised of five chapters; each chapter covers one stage of the process. Chapter 1 tackles the satellite remote sensing imaging and its cartographic significance. Chapter 2 discusses the production processes for extracting information from satellite data. The next chapter covers the methods for combining satellite-derived information with that obtained from conventional sources. Chapter 4 deals with design and semiology for cartographic representation, and Chapter 5 pre
A hand-actuated insertion tool includes a handle assembly, an elongated hollow tubular outer support tube, an elongated inner pull rod, and a coupling arrangement. The handle assembly has a first handle member and a second handle member pivoted to a member for movement between unactuated and actuated positions. The tube is attached in a fixed relation to a handle member. The rod is mounted within the tube for sliding movement relative thereto between home and retracted positions. The coupling arrangement pivotally connects the rod to the second handle member such that the rod will undergo sliding movement from the home position to the retracted positions relative to the tube as the second handle member is moved from the unactuated position to the actuated position adjacent to the first handle member. (author)
Ikeda, Kohei; Higashi, Toshio; Sugawara, Kenichi; Tomori, Kounosuke; Kinoshita, Hiroshi; Kasai, Tatsuya
The effect of visual and auditory enhancements of finger movement on corticospinal excitability during motor imagery (MI) was investigated using the transcranial magnetic stimulation technique. Motor-evoked potentials were elicited from the abductor digit minimi muscle during MI with auditory, visual and, auditory and visual information, and no…
Adams, I.L.J.; Lust, J.M.; Wilson, P.H.; Steenbergen, B.
Children with impaired motor coordination (or Development Coordination Disorder - DCD) have difficulty with the predictive control of movements, evidenced by cross-sectional studies that show impaired motor imagery and action planning abilities. What remains unclear is whether this deficit in
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.
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.
In this paper, the author discusses the regulatory role of the state and legal norms, in market economy, especially in so-called transition countries. Legal policy, and other questions of the state and free market economy are here closely connected, because the state must ensure with legal norms that economic processes are not interrupted: only the state can establish the legal basis for a market economy. The free market’s invisible hand is acting in questions such as: what is to be produced,...
Ma, Zhou; Ben-Tzvi, Pinhas; Danoff, Jerome
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.
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.
Faber, Tim W; van Elk, Michiel; Jonas, Kai J
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.
Reeder Anthony I
Full Text Available Abstract Background To examine the extent and nature of alcohol imagery on New Zealand (NZ television, a content analysis of 98 hours of prime-time television programs and advertising was carried out over 7 consecutive days' viewing in June/July 2004. The main outcome measures were number of scenes in programs, trailers and advertisements depicting alcohol imagery; the extent of critical versus neutral and promotional imagery; and the mean number of scenes with alcohol per hour, and characteristics of scenes in which alcohol featured. Results There were 648 separate depictions of alcohol imagery across the week, with an average of one scene every nine minutes. Scenes depicting uncritical imagery outnumbered scenes showing possible adverse health consequences of drinking by 12 to 1. Conclusion The evidence points to a large amount of alcohol imagery incidental to storylines in programming on NZ television. Alcohol is also used in many advertisements to market non-alcohol goods and services. More attention needs to be paid to the extent of alcohol imagery on television from the industry, the government and public health practitioners. Health education with young people could raise critical awareness of the way alcohol imagery is presented on television.
Stratton, Valerie N.; Zalanowski, Annette
Paired associate memory was tested with imagery and repetition instructions, with and without background music. Subjects were 64 students enrolled in an introductory psychology course. Music was found to have no effect with imagery instructions, but significantly improved performance with the repetition instructions. Music had different effects on…
Polland, Mark J.
In order to investigate the relationship between mental imagery and creative problem solving, a study of 44 separate accounts reporting mental imagery experiences associated with creative discoveries were examined. The data included 29 different scientists, among them Albert Einstein and Stephen Hawking, and 9 artists, musicians, and writers,…
Keogh, Rebecca; Pearson, Joel
Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage. PMID:22195024
Full Text Available Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.
Keogh, Rebecca; Pearson, Joel
Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.
Fisker, Maja H; Ebbehøj, Niels E; Vejlstrup, Søren Grove
Objective Occupational hand eczema has adverse health and socioeconomic impacts for the afflicted individuals and society. Prevention and treatment strategies are needed. This study aimed to assess the effectiveness of an educational intervention on sickness absence, quality of life and severity...... of hand eczema. Methods PREVEX (PreVention of EXema) is an individually randomized, parallel-group superiority trial investigating the pros and cons of one-time, 2-hour, group-based education in skin-protective behavior versus treatment as usual among patients with newly notified occupational hand eczema...
van Rompay, Thomas J.L.; Fransen, M.L.; Borgelink, B.; Brassett, J.; McDonnell, J.; Malpass, M.; Hekkert, P.P.M.; Ludden, G.D.S.
Based on embodiment research linking visual-spatial design parameters to symbolic meaning portrayal, this study investigates to what extent location of imagery on product packaging and visual devices portraying movement (i.e., an arrow indicating movement along an upward-headed or downward-headed
Lowe, Robyn; Menzies, Ross; Packman, Ann; O'Brian, Sue; Onslow, Mark
Adults who stutter are at risk of developing a range of psychological conditions. Social anxiety disorder is the most common anxiety disorder associated with stuttering. Observer perspective imagery is one cognitive process involved in the maintenance of some anxiety disorders. This involves viewing images as if looking at the self from the perspective of another. In contrast, the field perspective involves looking out from the self at the surrounding environment. The purpose of this study was to assess the presence of observer perspective imagery with stuttering. The authors administered the Hackmann, Surawy and Clark (1998) semi-structured interview to 30 adults who stutter and 30 controls. Group images and impressions were compared for frequency, perspective recalled and emotional valence. The stuttering group was significantly more likely than controls to recall images and impressions from an observer rather than a field perspective for anxious situations. It is possible the present results could reflect the same attentional processing bias that occurs with anxiety disorders in the non-stuttering population. These preliminary results provide an explanation for the persistence of conditions such as social anxiety disorder with stuttering. Clinical implications are discussed.
Flynn, Theresa A; Jones, Brittney A; Ausderau, Karla K
We examined the effects of a guided imagery intervention on perceived stress in pregnant adolescents. Thirty-five pregnant adolescents recruited from a local alternative education program participated in a guided imagery intervention. Participants listened to a pregnancy-specific guided imagery recording on four separate occasions during their pregnancies. Perceived stress was measured immediately before and after each session using the Perceived Stress Measure-9 (PSM-9). Participants' pre- and postsession PSM-9 scores for three of the four sessions demonstrated a significant reduction in stress. Participants' baseline stress levels also decreased significantly across the four listening sessions. The greatest reductions in stress within and between sessions occurred in the early sessions, with effects diminishing over time. Pregnant teens experienced initial short- and long-term stress reduction during a guided imagery intervention, supporting the use of guided imagery to reduce stress in pregnant adolescents. Copyright © 2016 by the American Occupational Therapy Association, Inc.
Rohde, S.; Weidauer, S.; Lanfermann, H.; Zanella, F.
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.)
Carmen Gago Alvarez
Full Text Available The purpose of this paper is to prove that, through exuberant sensuous imagery - the strange tropical setting, the mystery of elements, light and darkness - Joseph Conrad, in his short-story "The Lagoon" describes and transmits Impressionistically, the dramatic story of a men surprised by his own act of cowardice, a man divided between loyalty to his own blood and love. This man, Arsat suffers a blockaded feeling towards himself because he failed to act when he had the occasion, and he missed it: he left his brother to die in the hands of the enemy while he. Arsat, escaped with his love Diamelen, to live in the "shadows" of "The Lagoon" - his own psychological, subconscious guilty conscience. The story starts with a description of nature, as motionless, and undefined as the plot still is: The forests, somber and dull, stood motionless and silent... In the stillness of the air ... minute blossoms seemed do have been bewitched into an immobility perfect and final. Nothing moved on the river (1 The purpose of this paper is to prove that, through exuberant sensuous imagery - the strange tropical setting, the mystery of elements, light and darkness - Joseph Conrad, in his short-story "The Lagoon" describes and transmits Impressionistically, the dramatic story of a men surprised by his own act of cowardice, a man divided between loyalty to his own blood and love. This man, Arsat suffers a blockaded feeling towards himself because he failed to act when he had the occasion, and he missed it: he left his brother to die in the hands of the enemy while he. Arsat, escaped with his love Diamelen, to live in the "shadows" of "The Lagoon" - his own psychological, subconscious guilty conscience. The story starts with a description of nature, as motionless, and undefined as the plot still is: The forests, somber and dull, stood motionless and silent... In the stillness of the air ... minute blossoms seemed do have been bewitched into an
Full Text Available ... Clean Hands Count Centers for Disease Control and Prevention (CDC) Loading... Unsubscribe from Centers for Disease Control and Prevention (CDC)? Cancel Unsubscribe Working... Subscribe Subscribed Unsubscribe 65K ...
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2015 Annals of Medical and Health Sciences Research | Published by Wolters Kluwer - Medknow. 473. Introduction ... diabetes.[2,3] Tropical diabetic hand syndrome is a terminology .... the importance of seeking medical attention immediately.
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Bhuyan, M. K.; Kar, Mithun Kumar; Neog, Debanga Raj
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.
Choi, Junyeong; Park, Jungsik; Park, Hanhoon; Park, Jong-Il
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.
Felix, Márcia Marques Dos Santos; Ferreira, Maria Beatriz Guimarães; da Cruz, Luciana Falcão; Barbosa, Maria Helena
To identify the evidence in the literature about relaxation therapy with guided imagery for postoperative pain management. Integrative review. PubMed, Lilacs, Cochrane, Embase, Web of Science, Scopus and Cinahl, between August 2006 and December 2016. Descriptors: Postoperative Pain, Imagery (Psychotherapy) and Guided Imagery. original studies published in English, Spanish and Portuguese. 291 studies were identified and eight were selected. Descriptive data analysis, presented in detail, with a summary of the knowledge produced in each study. In the primary studies included, the use of guided imagery associated with other complementary therapies was highlighted: hand and foot "M" technique, education on postoperative pain management with analgesic drugs, relaxation exercises, respiration exercises, meditation, soothing biorhythmic music combined with positive and encouraging assertions and music with nature sounds. The knowledge synthesis resulting from this study indicates that evidence could be identified on the use of guided imagery associated with relaxation therapy as a complementary approach to drug analgesia in postoperative pain control strengthens its indication for nursing practice. This evidence, however, demonstrates that the quality of the use of this therapy is limited, and it is necessary to carry out new randomized clinical studies to fill the existing gaps in this topic. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
Full Text Available Introduction: The present study assessed whether motor imagery (MI produces electromyographic activation in specific muscles of the upper limb during a hand grasping and arm-lifting task in healthy volunteers, patients after stroke, or with Parkinson's disease. Electromyographic (EMG activation was compared under three conditions: MI, physical execution (PE, and rest. The task is clinically relevant unilateral executed movement using open muscle chains.Methods: In a cross-sectional study EMG activation was measured in four muscles: M. deltoideus pars clavicularis, M. biceps brachii, M. extensor digitorum, M. flexor carpi radialis. MI ability was evaluated with mental rotation, mental chronometry and the Kinaesthetic and Visual Imagery Questionnaire. Cognitive performance was screened with the Mini-Mental State Examination.Results: Twenty-two participants (11 females, age 52.6 ±15.8, age range 21 to 72 were included: ten healthy volunteers, seven patients after stroke (time after stroke onset 16.3 ± 24.8 months, and five patients with Parkinson's disease (disease duration 60.4 ± 24.5 months. Overall Mini-Mental State Examination scores ranged between 27 and 30. An increased EMG activation during MI compared to rest condition was observed in M. deltoideus pars clavicularis and M. biceps brachii across all participants (p-value = 0.001, p = 0.007. Seven participants (two healthy volunteers, three patients after stroke and two patients with Parkinson's disease showed a EMG activation during MI of the hand grasping and arm-lifting task in at least one of the target muscles. No correlation between EMG activation during MI and scores of three MI ability assessments were found.Conclusions: The findings suggest that MI can yield subliminal EMG activation. However, that might vary on individual basis. It remains unclear what parameters contribute to or inhibit an EMG activation during MI. Future investigations should determine factors that influence
Shafir, Tal; Tsachor, Rachelle P; Welch, Kathleen B
We have recently demonstrated that motor execution, observation, and imagery of movements expressing certain emotions can enhance corresponding affective states and therefore could be used for emotion regulation. But which specific movement(s) should one use in order to enhance each emotion? This study aimed to identify, using Laban Movement Analysis (LMA), the Laban motor elements (motor characteristics) that characterize movements whose execution enhances each of the basic emotions: anger, fear, happiness, and sadness. LMA provides a system of symbols describing its motor elements, which gives a written instruction (motif) for the execution of a movement or movement-sequence over time. Six senior LMA experts analyzed a validated set of video clips showing whole body dynamic expressions of anger, fear, happiness and sadness, and identified the motor elements that were common to (appeared in) all clips expressing the same emotion. For each emotion, we created motifs of different combinations of the motor elements common to all clips of the same emotion. Eighty subjects from around the world read and moved those motifs, to identify the emotion evoked when moving each motif and to rate the intensity of the evoked emotion. All subjects together moved and rated 1241 motifs, which were produced from 29 different motor elements. Using logistic regression, we found a set of motor elements associated with each emotion which, when moved, predicted the feeling of that emotion. Each emotion was predicted by a unique set of motor elements and each motor element predicted only one emotion. Knowledge of which specific motor elements enhance specific emotions can enable emotional self-regulation through adding some desired motor qualities to one's personal everyday movements (rather than mimicking others' specific movements) and through decreasing motor behaviors which include elements that enhance negative emotions.
Full Text Available We have recently demonstrated that motor execution, observation and imagery of movements expressing certain emotions can enhance corresponding affective states and therefore could be used for emotion regulation. But which specific movement(s should one use in order to enhance each emotion? This study aimed to identify, using Laban Movement Analysis (LMA, the Laban motor elements (motor characteristics that characterize movements whose execution enhances each of the basic emotions: anger, fear happiness, and sadness. LMA provides a system of symbols describing its motor elements, which gives a written instruction (motif for the execution of a movement or movement-sequence over time. Six senior LMA experts analyzed a validated set of video clips showing whole body dynamic expressions of anger, fear, happiness and sadness, and identified the motor elements that were common to (appeared in all clips expressing the same emotion. For each emotion, we created motifs of different combinations of the motor elements common to all clips of the same emotion. Eighty subjects from around the world read and moved those motifs, to identify the emotion evoked when moving each motif and to rate the intensity of the evoked emotion. All subjects together moved and rated 1241 motifs, which were produced from 29 different motor elements. Using logistic regression, we found a set of motor elements associated with each emotion which, when moved, predicted the feeling of that emotion. Each emotion was predicted by a unique set of motor elements and each motor element predicted only one emotion. Knowledge of which specific motor elements enhance specific emotions can enable emotional self-regulation through adding some desired motor qualities to one’s personal everyday movements (rather than mimicking others’ specific movements and through decreasing motor behaviors which include elements that enhance negative emotions.
Debarnot, Ursula; Guillot, Aymeric
When people listen to music, they hear beat and a metrical structure in the rhythm; these perceived patterns enable coordination with the music. A clear correspondence between the tempo of actual movement (e.g., walking) and that of music has been demonstrated, but whether similar coordination occurs during motor imagery is unknown. Twenty participants walked naturally for 8m, either physically or mentally, while listening to slow and fast music, or not listening to anything at all (control condition). Executed and imagined walking times were recorded to assess the temporal congruence between physical practice (PP) and motor imagery (MI). Results showed a difference when comparing slow and fast time conditions, but each of these durations did not differ from soundless condition times, hence showing that body movement may not necessarily change in order to synchronize with music. However, the main finding revealed that the ability to achieve temporal congruence between PP and MI times was altered when listening to either slow or fast music. These data suggest that when physical movement is modulated with respect to the musical tempo, the MI efficacy of the corresponding movement may be affected by the rhythm of the music. Practical applications in sport are discussed as athletes frequently listen to music before competing while they mentally practice their movements to be performed. Copyright © 2014 Elsevier B.V. All rights reserved.
Boyer, Doug M; Yapuncich, Gabriel S; Chester, Stephen G B; Bloch, Jonathan I; Godinot, Marc
Questions surrounding the origin and early evolution of primates continue to be the subject of debate. Though anatomy of the skull and inferred dietary shifts are often the focus, detailed studies of postcrania and inferred locomotor capabilities can also provide crucial data that advance understanding of transitions in early primate evolution. In particular, the hand skeleton includes characteristics thought to reflect foraging, locomotion, and posture. Here we review what is known about the early evolution of primate hands from a comparative perspective that incorporates data from the fossil record. Additionally, we provide new comparative data and documentation of skeletal morphology for Paleogene plesiadapiforms, notharctines, cercamoniines, adapines, and omomyiforms. Finally, we discuss implications of these data for understanding locomotor transitions during the origin and early evolutionary history of primates. Known plesiadapiform species cannot be differentiated from extant primates based on either intrinsic hand proportions or hand-to-body size proportions. Nonetheless, the presence of claws and a different metacarpophalangeal [corrected] joint form in plesiadapiforms indicate different grasping mechanics. Notharctines and cercamoniines have intrinsic hand proportions with extremely elongated proximal phalanges and digit rays relative to metacarpals, resembling tarsiers and galagos. But their hand-to-body size proportions are typical of many extant primates (unlike those of tarsiers, and possibly Teilhardina, which have extremely large hands). Non-adapine adapiforms and omomyids exhibit additional carpal features suggesting more limited dorsiflexion, greater ulnar deviation, and a more habitually divergent pollex than observed plesiadapiforms. Together, features differentiating adapiforms and omomyiforms from plesiadapiforms indicate increased reliance on vertical prehensile-clinging and grasp-leaping, possibly in combination with predatory behaviors in
Bisignani, W.T.; Greenhouse, S.C.
A research programme is described which has as its objective the automated characterization of neurological tissue regions from autoradiographs by utilizing hybrid-resolution image processing techniques. An experimental system is discussed which includes raw imagery, scanning an digitizing equipments, feature-extraction algorithms, and regional characterization techniques. The parameters extracted by these algorithms are presented as well as the regional characteristics which are obtained by operating on the parameters with statistical sampling techniques. An approach is presented for validating the techniques and initial experimental results are obtained from an anlysis of an autoradiograph of a region of the hypothalamus. An extension of these automated techniques to other biomedical research areas is discussed as well as the implications of applying automated techniques to biomedical research problems. (author)
Telles, Thiago; Barroso, Renato; Barbosa, Augusto Carvalho; Salgueiro, Diego Fortes de Souza; Colantonio, Emilson; Andries Júnior, Orival
This study investigated the effects of hand paddles, parachute and hand paddles plus parachute on the inter-limb coordination of butterfly swimming. Thirteen male swimmers were evaluated in four random maximal intensity conditions: without equipment, with hand paddles, with parachute and with hand paddles + parachute. Arm and leg stroke phases were identified by 2D video analysis to calculate the total time gap (T1: time between hands' entry in the water and high break-even point of the first undulation; T2: time between the beginning of the hand's backward movement and low break-even point of the first undulation; T3: time between the hand's arrival in a vertical plane to the shoulders and high break-even point of the second undulation; T4: time between the hand's release from the water and low break-even point of the second undulation). The swimming velocity was reduced and T1, T2 and T3 increased in parachute and hand paddles + parachute. No changes were observed in T4. Total time gap decreased in parachute and hand paddles + parachute. It is concluded that hand paddles do not influence the arm-to-leg coordination in butterfly, while parachute and hand paddles + parachute do change it, providing a greater propulsive continuity.
Gravano, Silvio; Zago, Myrka; Lacquaniti, Francesco
There is considerable evidence that gravitational acceleration is taken into account in the interaction with falling targets through an internal model of Earth gravity. Here we asked whether this internal model is accessed also when target motion is imagined rather than real. In the main experiments, naïve participants grasped an imaginary ball, threw it against the ceiling, and caught it on rebound. In different blocks of trials, they had to imagine that the ball moved under terrestrial gravity (1g condition) or under microgravity (0g) as during a space flight. We measured the speed and timing of the throwing and catching actions, and plotted ball flight duration versus throwing speed. Best-fitting duration-speed curves estimate the laws of ball motion implicit in the participant's performance. Surprisingly, we found duration-speed curves compatible with 0g for both the imaginary 0g condition and the imaginary 1g condition, despite the familiarity with Earth gravity effects and the added realism of performing the throwing and catching actions. In a control experiment, naïve participants were asked to throw the imaginary ball vertically upwards at different heights, without hitting the ceiling, and to catch it on its way down. All participants overestimated ball flight durations relative to the durations predicted by the effects of Earth gravity. Overall, the results indicate that mental imagery of motion does not have access to the internal model of Earth gravity, but resorts to a simulation of visual motion. Because visual processing of accelerating/decelerating motion is poor, visual imagery of motion at constant speed or slowly varying speed appears to be the preferred mode to perform the tasks. Copyright © 2017 Elsevier Ltd. All rights reserved.
Full Text Available Since a few years, micro UAS (unmanned aerial systems with vertical take off and landing capabilities like quadro- or octocopter are used as sensor platform for Aerophotogrammetry. Since the restricted payload of micro UAS with a total weight up of 5 kg (payload only up to 1.5 kg, these systems are often equipped with small format cameras. These cameras can be classified as amateur cameras and it is often the case, that these systems do not meet the requirements of a geometric stable camera for photogrammetric measurement purposes. However, once equipped with a suitable camera system, an UAS is an interesting alternative to expensive manned flights for small areas. The operating flight height of the above described UAS is about 50 up to 150 meters above ground level. This low flight height lead on the one hand to a very high spatial resolution of the aerial imagery. Depending on the cameras focal length and the sensor's pixel size, the ground sampling distance (GSD is usually about 1 up to 5 cm. This high resolution is useful especially for the automatic generation of homologous tie-points, which are a precondition for the image alignment (bundle block adjustment. On the other hand, the image scale depends on the object's height and the UAV operating height. Objects like mine heaps or construction sites show high variations of the object's height. As a result, operating the UAS with a constant flying height will lead to high variations in the image scale. For some processing approaches this will lead to problems e.g. the automatic tie-point generation in stereo image pairs. As precondition to all DEM generating approaches, first of all a geometric stable camera, sharp images are essentially. Well known calibration parameters are necessary for the bundle adjustment, to control the exterior orientations. It can be shown, that a simultaneous on site camera calibration may lead to misaligned aerial images. Also, the success rate of an automatic tie
Full Text Available Eczema, the commonest disorders afflicting the hands, is also the commonest occupational skin disease (OSD. In the dermatology outpatient departments, only the severe cases are diagnosed since patients rarely report with early hand dermatitis. Mild forms are picked up only during occupational screening. Hand eczema (HE can evolve into a chronic condition with persistent disease even after avoiding contact with the incriminated allergen / irritant. The important risk factors for hand eczema are atopy (especially the presence of dermatitis, wet work, and contact allergy. The higher prevalence in women as compared to men in most studies is related to environmental factors and is mainly applicable to younger women in their twenties. Preventive measures play a very important role in therapy as they enable the affected individuals to retain their employment and livelihood. This article reviews established preventive and therapeutic options and newer drugs like alitretinoin in hand eczema with a mention on the etiology and morphology. Identifying the etiological factors is of paramount importance as avoiding or minimizing these factors play an important role in treatment.
Ma, Chaolin; Ma, Xuan; Fan, Jing; He, Jiping
It is disputed whether those neurons in the primary motor cortex (M1) that encode hand orientation constitute an independent channel for orientation control in reach-to-grasp behaviors. Here, we trained two monkeys to reach forward and grasp objects positioned in the frontal plane at different orientation angles, and simultaneously recorded the activity of M1 neurons. Among the 2235 neurons recorded in M1, we found that 18.7% had a high correlation exclusively with hand orientation, 15.9% with movement direction, and 29.5% with both movement direction and hand orientation. The distributions of neurons encoding hand orientation and those encoding movement direction were not uniform but coexisted in the same region. The trajectory of hand rotation was reproduced by the firing patterns of the orientation-related neurons independent of the hand reaching direction. These results suggest that hand orientation is an independent component for the control of reaching and grasping activity.
With the rising popularity of personal mobile devices, from smartphones to tablets, an increasing number of colleges are asking students and teachers to bring their own technology to class. The so-called bring your own device, or BYOD, movement promises easier access to resources such as textbooks and educational services for students, and…
Hall, C. R.; Munroe-Chandler, K. J.; Fishburne, G. J.; Hall, N. D.
Athletes of all ages report using imagery extensively to enhance their sport performance. The Sport Imagery Questionnaire (Hall, Mack, Paivio, & Hausenblas, 1998) was developed to assess cognitive and motivational imagery used by adult athletes. No such instrument currently exists to measure the use of imagery by young athletes. The aim of the…
Hand Hygiene When and How August 2009 How to handrub? How to handwash? RUB HANDS FOR HAND HYGIENE! WASH HANDS WHEN VISIBLY SOILED Duration of the ... its use. When? YOUR 5 MOMENTS FOR HAND HYGIENE 1 BEFORETOUCHINGA PATIENT 2 B P ECFLOER R ...
Vasilyev, Anatoly; Liburkina, Sofya; Yakovlev, Lev; Perepelkina, Olga; Kaplan, Alexander
Motor imagery (MI) is considered to be a promising cognitive tool for improving motor skills as well as for rehabilitation therapy of movement disorders. It is believed that MI training efficiency could be improved by using the brain-computer interface (BCI) technology providing real-time feedback on person's mental attempts. While BCI is indeed a convenient and motivating tool for practicing MI, it is not clear whether it could be used for predicting or measuring potential positive impact of the training. In this study, we are trying to establish whether the proficiency in BCI control is associated with any of the neurophysiological or psychological correlates of motor imagery, as well as to determine possible interrelations among them. For that purpose, we studied motor imagery in a group of 19 healthy BCI-trained volunteers and performed a correlation analysis across various quantitative assessment metrics. We examined subjects' sensorimotor event-related EEG events, corticospinal excitability changes estimated with single-pulse transcranial magnetic stimulation (TMS), BCI accuracy and self-assessment reports obtained with specially designed questionnaires and interview routine. Our results showed, expectedly, that BCI performance is dependent on the subject's capability to suppress EEG sensorimotor rhythms, which in turn is correlated with the idle state amplitude of those oscillations. Neither BCI accuracy nor the EEG features associated with MI were found to correlate with the level of corticospinal excitability increase during motor imagery, and with assessed imagery vividness. Finally, a significant correlation was found between the level of corticospinal excitability increase and kinesthetic vividness of imagery (KVIQ-20 questionnaire). Our results suggest that two distinct neurophysiological mechanisms might mediate possible effects of motor imagery: the non-specific cortical sensorimotor disinhibition and the focal corticospinal excitability increase
Fooken, Jolande; Lalonde, Kathryn M; Mann, Gurkiran K; Spering, Miriam
Eye and hand movements are closely linked when performing everyday actions. We conducted a perceptual-motor training study to investigate mutually beneficial effects of eye and hand movements, asking whether training in one modality benefits performance in the other. Observers had to predict the future trajectory of a briefly presented moving object, and intercept it at its assumed location as accurately as possible with their finger. Eye and hand movements were recorded simultaneously. Different training protocols either included eye movements or a combination of eye and hand movements with or without external performance feedback. Eye movement training did not transfer across modalities: Irrespective of feedback, finger interception accuracy and precision improved after training that involved the hand, but not after isolated eye movement training. Conversely, eye movements benefited from hand movement training or when external performance feedback was given, thus improving only when an active interceptive task component was involved. These findings indicate only limited transfer across modalities. However, they reveal the importance of creating a training task with an active sensorimotor decision to improve the accuracy and precision of eye and hand movements.
Pavlov, Alexey N.; Maksimenko, Vladimir A.; Runnova, Anastasiya E.; Khramova, Marina V.; Pisarchik, Alexander N.
We study abilities of the wavelet-based multifractal analysis in recognition specific dynamics of electrical brain activity associated with real and imaginary movements. Based on the singularity spectra we analyze electroencephalograms (EEGs) acquired in untrained humans (operators) during imagination of hands movements, and show a possibility to distinguish between the related EEG patterns and the recordings performed during real movements or the background electrical brain activity. We discuss how such recognition depends on the selected brain region.
El Haj, Mohamad; Nandrino, Jean-Louis; Antoine, Pascal; Boucart, Muriel; Lenoble, Quentin
This study assessed whether specific eye movement patterns are observed during emotional autobiographical retrieval. Participants were asked to retrieve positive, negative and neutral memories while their scan path was recorded by an eye-tracker. Results showed that positive and negative emotional memories triggered more fixations and saccades but shorter fixation duration than neutral memories. No significant differences were observed between emotional and neutral memories for duration and amplitude of saccades. Positive and negative retrieval triggered similar eye movement (i.e., similar number of fixations and saccades, fixation duration, duration of saccades, and amplitude of saccades). Interestingly, the participants reported higher visual imagery for emotional memories than for neutral memories. The findings demonstrate similarities and differences in eye movement during retrieval of neutral and emotional memories. Eye movement during autobiographical retrieval seems to be triggered by the creation of visual mental images as the latter are indexed by autobiographical reconstruction. Copyright © 2016. Published by Elsevier B.V.
Santello, Marco; Bianchi, Matteo; Gabiccini, Marco; Ricciardi, Emiliano; Salvietti, Gionata; Prattichizzo, Domenico; Ernst, Marc; Moscatelli, Alessandro; Jörntell, Henrik; Kappers, Astrid M. L.; Kyriakopoulos, Kostas; Albu-Schäffer, Alin; Castellini, Claudio; Bicchi, Antonio
The term 'synergy' - from the Greek synergia - means 'working together'. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project ;The Hand Embodied; (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.
O. A. Mokienko
Full Text Available The aim of study was to assess the feasibility of motor imagery supported brain-computer interface in patients with hemiparesis. 13 patients with central paresis of the hand and 15 healthy volunteers were learning to control EEG-based interface with feedback. No differences on interface control quality were found between patients and healthy subjects. The trainings were accompanied by the desynchronization of sensorimotor rhythm. In patients with cortical damage the source of EEG-activity was dislocated.
Krutik, Vitaliy; Doo, Burt; Townsend, William T.; Hauptman, Traveler; Crowell, Adam; Zenowich, Brian; Lawson, John
A robotic device has a base and at least one finger having at least two links that are connected in series on rotary joints with at least two degrees of freedom. A brushless motor and an associated controller are located at each joint to produce a rotational movement of a link. Wires for electrical power and communication serially connect the controllers in a distributed control network. A network operating controller coordinates the operation of the network, including power distribution. At least one, but more typically two to five, wires interconnect all the controllers through one or more joints. Motor sensors and external world sensors monitor operating parameters of the robotic hand. The electrical signal output of the sensors can be input anywhere on the distributed control network. V-grooves on the robotic hand locate objects precisely and assist in gripping. The hand is sealed, immersible and has electrical connections through the rotary joints for anodizing in a single dunk without masking. In various forms, this intelligent, self-contained, dexterous hand, or combinations of such hands, can perform a wide variety of object gripping and manipulating tasks, as well as locomotion and combinations of locomotion and gripping.
Recent research findings indicate that with older adulthood, there are functional decrements in spatial cognition and more specially, in the ability to mentally represent and effectively plan motor actions. A typical finding is a significant over- or underestimation of one's actual physical abilities with movement planning-planning that has implications for movement efficiency and physical safety. A practical, daily life example is estimation of reachability--a situation that for the elderly may be linked with fall incidence. A strategy used to mentally represent action is the use of motor imagery--an ability that also declines with advancing older age. This brief review highlights research findings on mental representation and motor imagery in the elderly and addresses the implications for improving movement efficiency and lowering the risk of movement-related injury. © The Author(s) 2013.
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Lund, Tamara Theresia; Agner, Tove
Hand eczema is a common disease, it affects young people, is often work-related, and the burden of the disease is significant for the individual as well as for society. Factors to be considered when choosing a treatment strategy are, among others, whether the eczema is acute or chronic, the sever...
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This video shows kids how to properly wash their hands, one of the most important steps we can take to avoid getting sick and spreading germs to others. Created: 3/8/2010 by Centers for Disease Control and Prevention (CDC). Date Released: 3/8/2010.
Full Text Available ... no cure tomorrow - Duration: 3:10. World Health Organization 75,585 views 3:10 Wash 'Em - Hand ... soap and water - Duration: 1:27. World Health Organization 224,180 views 1:27 The five moments ...
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Kauffman, J.A.; Slump, Cornelis H.; Bernelot Moens, H.J.
Biometric verification and identification methods of medical images can be used to find possible inconsistencies in patient records. Such methods may also be useful for forensic research. In this work we present a method for identifying patients by their hand radiographs. We use active appearance
Full Text Available ... today; no cure tomorrow - Duration: 3:10. World Health Organization 72,885 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Jefferson Health 410,052 views 5:46 'It's in your ...
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In this paper we discuss manipulatives and hands-on investigations for Calculus involving volume, arc length, and surface area to motivate and develop formulae which can then be verified using techniques of integration. Pre-service teachers in calculus courses using these activities experience a classroom in which active learning is encouraged and…
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Pankiewicz, Philip R.
Presents five hands-on activities that allow students to detect, measure, reduce, and eliminate moisture. Students make a humidity detector and a hygrometer, examine the effects of moisture on different substances, calculate the percent of water in a given food, and examine the absorption potential of different desiccants. (MDH)
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Full Text Available ... action today; no cure tomorrow - Duration: 3:10. World Health Organization 72,319 views 3:10 Wash 'Em - Hand ... handwash? With soap and water - Duration: 1:27. World Health Organization 205,878 views 1:27 Germ Smart - Wash ...
Weisgarber, Sherry L.; Van Doren, Lisa; Hackathorn, Merrianne; Hannibal, Joseph T.; Hansgen, Richard
This publication is a collection of 13 hands-on activities that focus on earth science-related activities and involve students in learning about growing crystals, tectonics, fossils, rock and minerals, modeling Ohio geology, geologic time, determining true north, and constructing scale-models of the Earth-moon system. Each activity contains…
Full Text Available ... Queue __count__/__total__ It’s YouTube. Uninterrupted. Loading... Want music and videos with zero ads? Get YouTube Red. ... 384 views 1:19 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Thomas Jefferson University & Jefferson ...
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Full Text Available ... Gorin 243,451 views 2:57 Hand Hygiene Dance - Duration: 3:15. mohd hafiz 34,146 views ... Language: English Location: United States Restricted Mode: Off History Help Loading... Loading... Loading... About Press Copyright Creators ...
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Full Text Available ... Em - Hand Hygiene Music Video - Duration: 5:46. Thomas Jefferson University & Jefferson Health 408,436 views 5: ... Prevention (CDC) 97,277 views 5:12 Loading more suggestions... Show more Language: English Location: United States ...
Mathews, Catherine E.; Monroe, Louise Nelson
A professional school and university collaboration enables elementary students and their teachers to explore hydrology concepts and realize the beneficial functions of wetlands. Hands-on experiences involve young students in determining water quality at field sites after laying the groundwork with activities related to the hydrologic cycle,…
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Full Text Available ... News 581,131 views 18:49 Just Good Music 24/7 ● Classic Live Radio classics. 1,406 ... 611,013 views 1:46 Hand hygiene FULL music video - Duration: 2:33. AlfredHealthTV 26,798 views ...
... work properly. There are many kinds of eye movement disorders. Two common ones are Strabismus - a disorder ... in "crossed eyes" or "walleye." Nystagmus - fast, uncontrollable movements of the eyes, sometimes called "dancing eyes" Some ...
... of Delirium Additional Content Medical News Overview of Movement Disorders By Hector A. Gonzalez-Usigli, MD, Professor ... Neurology, HE UMAE Centro Médico Nacional de Occidente; Movement Disorders Clinic, Neurology at IMSS Alberto Espay, MD, ...
National Oceanic and Atmospheric Administration, Department of Commerce — All imagery was collected during the 2012 Spring flying season during leaf-off conditions for deciduous vegetation in the State of Georgia. The sun angle was at...
Moran, Daniel J; O'Brien, Richard M
An emetophobic child is nonresponsive to conventional systematic desensitization and has her anxiety responses counterconditioned by using Competence Imagery instead of physical relaxation responses while progressing through her fear hierarchy.
Santo F. Di Nuovo
Full Text Available Mental Imagery (i.e., processing of objects’ properties and spatial relations, including the ability of mentally rotating and manipulating objects in the space, is relevant for movement and its development, and particularly for rehabilitation of motor skills. Few studies aimed at assessing the efficacy of imagery training used objective scores of Mental Imagery skills, preferring self-evaluations of these abilities reported by the subjects themselves. The aim of the paper was to explore the relevance of Mental Imagery, assessed by objective tests, in predicting the improvement of balance skills, after a standard rehabilitative training in orthopaedic settings; taking into account also emotional variables as anxiety and depression. A controlled study was conducted assessing the changes in balance skills after rehabilitative training. The sample was composed of 30 orthopaedic inpatients (females 66.7%, age range 47-91 years. To measure the dependent variable for pre-post assessment, B-scale from Performance-oriented mobility assessment test (POMA was used. Independent variables were measured using Mental Imagery Test, Mini-Mental State Examination, Hamilton Depression Rating Scale and Hamilton Anxiety Rating Scales. The best predictor of improvement in balance after rehabilitation is the Mental Imagery test, followed by age and mental efficiency. Anxiety predicts negatively the improvement, while education and depression appear to influence less the rehabilitation process. In conclusion, the study demonstrates that mental imagery is relevant in helping balance rehabilitation. A training of this function could be essential for clinical practice; the trainers should assess preliminarily the subject's attitude and ability to use mental imagery, with the aim of optimizing the rehabilitative process.
Haith, Adrian M; Pakpoor, Jina; Krakauer, John W
Initiating a movement in response to a visual stimulus takes significantly longer than might be expected on the basis of neural transmission delays, but it is unclear why. In a visually guided reaching task, we forced human participants to move at lower-than-normal reaction times to test whether normal reaction times are strictly necessary for accurate movement. We found that participants were, in fact, capable of moving accurately ∼80 ms earlier than their reaction times would suggest. Reaction times thus include a seemingly unnecessary delay that accounts for approximately one-third of their duration. Close examination of participants' behavior in conventional reaction-time conditions revealed that they generated occasional, spontaneous errors in trials in which their reaction time was unusually short. The pattern of these errors could be well accounted for by a simple model in which the timing of movement initiation is independent of the timing of movement preparation. This independence provides an explanation for why reaction times are usually so sluggish: delaying the mean time of movement initiation relative to preparation reduces the risk that a movement will be initiated before it has been appropriately prepared. Our results suggest that preparation and initiation of movement are mechanistically independent and may have a distinct neural basis. The results also demonstrate that, even in strongly stimulus-driven tasks, presentation of a stimulus does not directly trigger a movement. Rather, the stimulus appears to trigger an internal decision whether to make a movement, reflecting a volitional rather than reactive mode of control. Copyright © 2016 the authors 0270-6474/16/363007-10$15.00/0.
Riisgaard Hansen, Thomas; Eriksson, Eva; Lykke-Olesen, Andreas
In this paper we explore the space in which movement based interaction takes place. We have in several projects explored how fixed and mobile cameras can be used in movement based interaction and will shortly describe these projects. Based on our experience with working with movement......-based interaction we will briefly introduce and discuss how learning, mapping and multi-user interaction are important when designing movement based interaction....
Calculation of temporal height changes for the determination of recent vertical crustal movements in northern, western, and southern Germany is described. Precise geodetic measurements and their analysis for the determination of recent crustal movements in north-eastern Iceland, western Venezuela, and central Peru are described. Determination of recent vertical crustal movements by leveling and gravity data; geodetic modeling of deformations and recent crustal movements; geodetic modeling of plate motions; and instrumental developments in geodetic measuring are discussed.
Buckley, Theresa M.
Electronic neural networks proposed for use in controlling robotic and prosthetic hands and exoskeletal or glovelike electromechanical devices aiding intact but nonfunctional hands. Specific to patient, who activates grasping motion by voice command, by mechanical switch, or by myoelectric impulse. Patient retains higher-level control, while lower-level control provided by neural network analogous to that of miniature brain. During training, patient teaches miniature brain to perform specialized, anthropomorphic movements unique to himself or herself.
Bonde, Lars Ole
4 original research articles, one essay, a classical article and two clinical papers documenting the development of theory, research and clinical practice within the receptive music therapy model [The Bonny Method of] Guided Imagery and Music.......4 original research articles, one essay, a classical article and two clinical papers documenting the development of theory, research and clinical practice within the receptive music therapy model [The Bonny Method of] Guided Imagery and Music....
Keogh, Rebecca; Pearson, Joel
Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance ...
Full Text Available Computer interaction via visually guided hand or finger movements is a ubiquitous part of daily computer usage in work or gaming. Surprisingly, however, little is known about the performance effects of using virtual limb representations versus simpler cursors. In this study 26 healthy right-handed adults performed cued index finger flexion-extension movements towards an on-screen target while wearing a data glove. They received each of four different types of real-time visual feedback: a simple circular cursor, a point light pattern indicating finger joint positions, a cartoon hand and a fully shaded virtual hand. We found that participants initiated the movements faster when receiving feedback in the form of a hand than when receiving circular cursor or point light feedback. This overall difference was robust for three out of four hand versus circle pairwise comparisons. The faster movement initiation for hand feedback was accompanied by a larger movement amplitude and a larger movement error. We suggest that the observed effect may be related to priming of hand information during action perception and execution affecting motor planning and execution. The results may have applications in the use of body representations in virtual reality applications.
The article examines the role of social movements in the development of scientific knowledge. Interactions between social movements and science in broad, historical terms are discussed. The relations between the new social movements of the 1960s and 1970s and changes in the contemporary scientific...
Holmes, Emily A; Mathews, Andrew
Mental imagery has been considered relevant to psychopathology due to its supposed special relationship with emotion, although evidence for this assumption has been conspicuously lacking. The present review is divided into four main sections: (1) First, we review evidence that imagery can evoke emotion in at least three ways: a direct influence on emotional systems in the brain that are responsive to sensory signals; overlap between processes involved in mental imagery and perception which can lead to responding "as if" to real emotion-arousing events; and the capacity of images to make contact with memories for emotional episodes in the past. (2) Second, we describe new evidence confirming that imagery does indeed evoke greater emotional responses than verbal representation, although the extent of emotional response depends on the image perspective adopted. (3) Third, a heuristic model is presented that contrasts the generation of language-based representations with imagery and offers an account of their differing effects on emotion, beliefs and behavior. (4) Finally, based on the foregoing review, we discuss the role of imagery in maintaining emotional disorders, and its uses in psychological treatment. Copyright 2010 Elsevier Ltd. All rights reserved.
Puhan Milo A
Full Text Available Abstract Background Evaluation of how Motor Imagery and conventional therapy (physiotherapy or occupational therapy compare to conventional therapy only in their effects on clinically relevant outcomes during rehabilitation of persons with stroke. Design Systematic review of the literature Methods We conducted an electronic database search in seven databases in August 2005 and also hand-searched the bibliographies of studies that we selected for the review. Two reviewers independently screened and selected all randomized controlled trials that compare the effects of conventional therapy plus Motor Imagery to those of only conventional therapy on stroke patients. The outcome measurements were: Fugl-Meyer Stroke Assessment upper extremity score (66 points and Action Research Arm Test upper extremity score (57 points. Due to the high variability in the outcomes, we could not pool the data statistically. Results We identified four randomized controlled trials from Asia and North America. The quality of the included studies was poor to moderate. Two different Motor imagery techniques were used (three studies used audiotapes and one study had occupational therapists apply the intervention. Two studies found significant effects of Motor Imagery in the Fugl-Meyer Stroke Assessment: Differences between groups amounted to 11.0 (1.0 to 21.0 and 3.2 (-4 to 10.3 respectively and in the Action Research Arm Test 6.1 (-6.2 to 18.4 and 15.8 (0.5 to 31.0 respectively. One study did not find a significant effect in the Fugl-Meyer Stroke Assessment and Color trail Test (p = 0.28 but in the task-related outcomes (p > 0.001. Conclusion Current evidence suggests that Motor imagery provides additional benefits to conventional physiotherapy or occupational therapy. However, larger and methodologically sounder studies should be conducted to assess the benefits of Motor imagery.
36 children in Grade 5 and 59 university students, all native speakers of Japanese, studied three types of priming stimuli in a mixed list: words written in hiragana (Japanese syllabary used in writing), words written in kanji (Chinese characters also used in writing), and pictures. They were then given a task involving completion of hiragana-word fragments: the task involved studied and nonstudied items. For both children and university students, words in hiragana produced the largest priming effects, that is, the words that had appeared in hiragana in the preceding study phase were generated more often in the test phase of word completion than the other two types of priming stimuli. This confirms that the perceptual priming effect depends much on data-driven processing. For both age groups, words in kanji produced nearly half the priming effects seen for hiragana-words. On the other hand, pictures had no priming effect for children but they had a similar effect to kanji-words for students. The discrepancy between kanji-words and pictures for children suggests that the former force the subject to read the words, which, possibly, activates the hiragana-words, while the latter do not necessarily force labelling the pictures. Among three kinds of imagery tests, the Verbalizer-Visualizer Questionnaire predicted priming scores for children and the Questionnaire upon Mental Imagery did so for students, but the Test of Visual Imagery Control did not predict the scores for either age group. This shows that children reporting habitual use of imagery and adults reporting vivid imagery have more pronounced perceptual priming effects. We conclude that the imagery ability based on self-judgments reflects real characteristics of the perceptual representation system of Tulving and Schacter (1990).
Li, Wenjing; Lieberman, Rich W.; Nie, Sixiang; Xie, Yihua; Eldred, Michael; Oyama, Jody
Diagnosing cervical cancer in a woman is a multi-step procedure involving examination of the cervix, possible biopsy and follow-up. It is open to subjective interpretation and highly dependent upon the skills of cytologists, colposcopists, and pathologists. In an effort to reduce the subjectiveness of the colposcopist-directed biopsy and to improve the diagnostic accuracy of colposcopy, we have developed new colposcopic imaging systems with accompanying computer aided diagnostic (CAD) techniques to guide a colposcopist in deciding if and where to biopsy. If the biopsy's histopathology, the identification of the disease state at the cellular and near-cellular level, is to be used as the gold standard for CAD, then the location of the histopathologic analysis must match exactly to the location of the biopsy tissue in the digital image. Otherwise, no matter how perfect the histopathology and the quality of the digital imagery, the two data sets cannot be matched and the true sensitivity and specificity of the CAD cannot be ascertained. We report here on new approaches to preserving, continuously, the location and orientation of a biopsy sample with respect to its location in the digital image of the cervix so as to preserve the exact spatial relationship throughout the mechanical aspects of the histopathologic analysis. This new approach will allow CAD to produce a linear diagnosis and pinpoint the location of the tissue under examination.
Nakano, Hideki; Kodama, Takayuki; Ukai, Kazumasa; Kawahara, Satoru; Horikawa, Shiori; Murata, Shin
In this study, we aimed to (1) translate the English version of the Kinesthetic and Visual Imagery Questionnaire (KVIQ), which assesses motor imagery ability, into Japanese, and (2) investigate the reliability and validity of the Japanese KVIQ. We enrolled 28 healthy adults in this study. We used Cronbach’s alpha coefficients to assess reliability reflected by the internal consistency. Additionally, we assessed validity reflected by the criterion-related validity between the Japanese KVIQ and the Japanese version of the Movement Imagery Questionnaire-Revised (MIQ-R) with Spearman’s rank correlation coefficients. The Cronbach’s alpha coefficients for the KVIQ-20 were 0.88 (Visual) and 0.91 (Kinesthetic), which indicates high reliability. There was a significant positive correlation between the Japanese KVIQ-20 (Total) and the Japanese MIQ-R (Total) (r = 0.86, p < 0.01). Our results suggest that the Japanese KVIQ is an assessment that is a reliable and valid index of motor imagery ability.
Full Text Available Non-invasive EEG-based Brain-Computer Interfaces (BCI can be promising for the motor neuro-rehabilitation of paraplegic patients. However, this shall require detailed knowledge of the abnormalities in the EEG signatures of paraplegic patients. The association of abnormalities in different subgroups of patients and their relation to the sensorimotor integration are relevant for the design, implementation and use of BCI systems in patient populations. This study explores the patterns of abnormalities of movement related cortical potentials (MRCP during motor imagery tasks of feet and right hand in patients with paraplegia (including the subgroups with/without central neuropathic pain and complete/incomplete injury patients and the level of distinctiveness of abnormalities in these groups using pattern classification. The most notable observed abnormalities were the amplified execution negativity and its slower rebound in the patient group. The potential underlying mechanisms behind these changes and other minor dissimilarities in patients’ subgroups, as well as the relevance to BCI applications, are discussed. The findings are of interest from a neurological perspective as well as for BCI-assisted neuro-rehabilitation and therapy.
Debarnot, Ursula; Maley, Laura; De Rossi, Danilo; Guillot, Aymeric
The present study aimed to investigate whether an interference task might impact the sleep-dependent consolidation process of a mentally learned sequence of movements. Thirty-two participants were subjected to a first training session through motor imagery (MI) or physical practice (PP) of a finger sequence learning task. After 2 h, half of the…
Full Text Available Stroke is a leading cause of disability worldwide. In this paper, a novel robot-assisted rehabilitation system based on motor imagery electroencephalography (EEG is developed for regular training of neurological rehabilitation for upper limb stroke patients. Firstly, three-dimensional animation was used to guide the patient image the upper limb movement and EEG signals were acquired by EEG amplifier. Secondly, eigenvectors were extracted by harmonic wavelet transform (HWT and linear discriminant analysis (LDA classifier was utilized to classify the pattern of the left and right upper limb motor imagery EEG signals. Finally, PC triggered the upper limb rehabilitation robot to perform motor therapy and gave the virtual feedback. Using this robot-assisted upper limb rehabilitation system, the patient's EEG of upper limb movement imagination is translated to control rehabilitation robot directly. Consequently, the proposed rehabilitation system can fully explore the patient's motivation and attention and directly facilitate upper limb post-stroke rehabilitation therapy. Experimental results on unimpaired participants were presented to demonstrate the feasibility of the rehabilitation system. Combining robot-assisted training with motor imagery-based BCI will make future rehabilitation therapy more effective. Clinical testing is still required for further proving this assumption.
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van der Kamp, J.; de Wit, M.M.; Masters, R.S.W.
We investigated whether the control of movement of the left hand is more likely to involve the use of allocentric information than movements performed with the right hand. Previous studies (Gonzalez et al. in J Neurophys 95:3496-3501, 2006; De Grave et al. in Exp Br Res 193:421-427, 2009) have
Full Text Available BACKGROUND: Motor imagery training is a promising rehabilitation strategy for stroke patients. However, few studies had focused on the neural mechanisms in time course of its cognitive process. This study investigated the cognitive alterations after left hemispheric ischemic stroke during motor imagery task. METHODOLOGY/PRINCIPAL FINDINGS: Eleven patients with ischemic stroke in left hemisphere and eleven age-matched control subjects participated in mental rotation task (MRT of hand pictures. Behavior performance, event-related potential (ERP and event-related (desynchronization (ERD/ERS in beta band were analyzed to investigate the cortical activation. We found that: (1 The response time increased with orientation angles in both groups, called "angle effect", however, stoke patients' responses were impaired with significantly longer response time and lower accuracy rate; (2 In early visual perceptual cognitive process, stroke patients showed hypo-activations in frontal and central brain areas in aspects of both P200 and ERD; (3 During mental rotation process, P300 amplitude in control subjects decreased while angle increased, called "amplitude modulation effect", which was not observed in stroke patients. Spatially, patients showed significant lateralization of P300 with activation only in contralesional (right parietal cortex while control subjects showed P300 in both parietal lobes. Stroke patients also showed an overall cortical hypo-activation of ERD during this sub-stage; (4 In the response sub-stage, control subjects showed higher ERD values with more activated cortical areas particularly in the right hemisphere while angle increased, named "angle effect", which was not observed in stroke patients. In addition, stroke patients showed significant lower ERD for affected hand (right response than that for unaffected hand. CONCLUSIONS/SIGNIFICANCE: Cortical activation was altered differently in each cognitive sub-stage of motor imagery after
Rosén, Birgitta; Ehrsson, H Henrik; Antfolk, Christian; Cipriani, Christian; Sebelius, Fredrik; Lundborg, Göran
Hand prostheses that are currently available on the market are used by amputees to only a limited extent, partly because of lack of sensory feedback from the artificial hand. We report a pilot study that showed how amputees can experience a robot-like advanced hand prosthesis as part of their own body. We induced a perceptual illusion by which touch applied to the stump of the arm was experienced from the artificial hand. This illusion was elicited by applying synchronous tactile stimulation to the hidden amputation stump and the robotic hand prosthesis in full view. In five people who had had upper limb amputations this stimulation caused referral touch sensation from the stump to the artificial hand, and the prosthesis was experienced more like a real hand. We also showed that this illusion can work when the amputee controls the movements of the artificial hand by recordings of the arm muscle activity with electromyograms. These observations indicate that the previously described "rubber hand illusion" is also valid for an advanced hand prosthesis, even when it has a robotic-like appearance.
Zhou, Aibao; Zhang, Yanchi; Yin, Yulong; Yang, Yang
Certain situations may not only cause people to misjudge external information but also distort people's perception of themselves. The present study is the first to report the mirrored hand illusion which could be generated when the experimenter imitated the fist-clenching movements of the subject synchronously. The subjects formed the illusion that the experimenter's hand was "something I can control" when being imitated synchronously. In addition, a sense of ownership over the alien hand was established by integrating multisensory signals and comparing these signals with preexisting body presentations. This method might represent a new avenue for research on the formation of self-consciousness. © The Author(s) 2015.
Longcamp, Marieke; Boucard, Céline; Gilhodes, Jean-Claude; Anton, Jean-Luc; Roth, Muriel; Nazarian, Bruno; Velay, Jean-Luc
Fast and accurate visual recognition of single characters is crucial for efficient reading. We explored the possible contribution of writing memory to character recognition processes. We evaluated the ability of adults to discriminate new characters from their mirror images after being taught how to produce the characters either by traditional pen-and-paper writing or with a computer keyboard. After training, we found stronger and longer lasting (several weeks) facilitation in recognizing the orientation of characters that had been written by hand compared to those typed. Functional magnetic resonance imaging recordings indicated that the response mode during learning is associated with distinct pathways during recognition of graphic shapes. Greater activity related to handwriting learning and normal letter identification was observed in several brain regions known to be involved in the execution, imagery, and observation of actions, in particular, the left Broca's area and bilateral inferior parietal lobules. Taken together, these results provide strong arguments in favor of the view that the specific movements memorized when learning how to write participate in the visual recognition of graphic shapes and letters.
De Visser, H.; Herder, J.L.
This paper presents the design of a body-powered voluntary closing prosthetic hand. It is argued that the movement of the fingers before establishing a grip is much less relevant for good control of the object held than the distribution of forces once the object has been contacted. Based on this
Full Text Available Vaughan P Nicholson,1 Justin WL Keogh,2–4 Nancy L Low Choy1 1School of Physiotherapy, Australian Catholic University, Brisbane, QLD, Australia; 2Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia; 3Human Potential Centre, AUT University, Auckland, New Zealand; 4Cluster for Health Improvement, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sunshine Coast, QLD, Australia Purpose: To investigate the influence of a single session of locomotor-based motor imagery training on motor learning and physical performance. Patients and methods: Thirty independent adults aged >65 years took part in the randomized controlled trial. The study was conducted within an exercise science laboratory. Participants were randomly divided into three groups following baseline locomotor testing: motor imagery training, physical training, and control groups. The motor imagery training group completed 20 imagined repetitions of a locomotor task, the physical training group completed 20 physical repetitions of a locomotor task, and the control group spent 25 minutes playing mentally stimulating games on an iPad. Imagined and physical performance times were measured for each training repetition. Gait speed (preferred and fast, timed-up-and-go, gait variability and the time to complete an obstacle course were completed before and after the single training session. Results: Motor learning occurred in both the motor imagery training and physical training groups. Motor imagery training led to refinements in motor planning resulting in imagined movements better matching the physically performed movement at the end of training. Motor imagery and physical training also promoted improvements in some locomotion outcomes as demonstrated by medium to large effect size improvements after training for fast gait speed and timed-up-and-go. There were no training effects on gait variability. Conclusion: A single session
Carbone, Giuseppe; Rossi, Cesare; Savino, Sergio
This paper describes two robotic hands that have been\\ud developed at University Federico II of Naples and at the\\ud University of Cassino. FEDERICA Hand and LARM Hand\\ud are described in terms of design and operational features.\\ud In particular, careful attention is paid to the differences\\ud between the above-mentioned hands in terms of transmission\\ud systems. FEDERICA Hand uses tendons and pulleys\\ud to drive phalanxes, while LARM Hand uses cross four-bar\\ud linkages. Results of experime...
Daluja, Sachin; Golenberg, Lavie; Cao, Alex; Pandya, Abhilash K; Auner, Gregory W; Klein, Michael D
Robotic surgery has gradually gained acceptance due to its numerous advantages such as tremor filtration, increased dexterity and motion scaling. There remains, however, a significant scope for improvement, especially in the areas of surgeon-robot interface and autonomous procedures. Previous studies have attempted to identify factors affecting a surgeon's performance in a master-slave robotic system by tracking hand movements. These studies relied on conventional optical or magnetic tracking systems, making their use impracticable in the operating room. This study concentrated on building an intrinsic movement capture platform using microcontroller based hardware wired to a surgical robot. Software was developed to enable tracking and analysis of hand movements while surgical tasks were performed. Movement capture was applied towards automated movements of the robotic instruments. By emulating control signals, recorded surgical movements were replayed by the robot's end-effectors. Though this work uses a surgical robot as the platform, the ideas and concepts put forward are applicable to telerobotic systems in general.