| Home | [1–10] << 11 12 13 14 15 16 17 18 19 20 >> [21–21] |
|
| Records | |||||
|---|---|---|---|---|---|
| Author | Harel Arzi; Tal Krasovsky; Moshe Pritsch; Dario G. Liebermann | ||||
| Title | Movement control in patients with shoulder instability: a comparison between patients after open surgery and nonoperated patients | Type | Journal Article | ||
| Year | 2014 | Publication | Journal of Shoulder and Elbow Surgery | Abbreviated Journal | |
| Volume | 23 | Issue | 7 | Pages | 982–992 |
| Keywords | Smoothness; kinesthesis; arm kinematics; shoulder instability; open surgery | ||||
| Abstract | Background Open surgery to correct shoulder instability is deemed to facilitate recovery of static and dynamic motor functions. Postoperative assessments focus primarily on static outcomes (e.g., repositioning accuracy). We introduce kinematic measures of arm smoothness to assess shoulder patients after open surgery and compare them with nonoperated patients. Performance among both groups of patients was hypothesized to differ. Postsurgery patients were expected to match healthy controls. Methods All participants performed pointing movements with the affected/dominant arm fully extended at fast, preferred, and slow speeds (36 trials per subject). Kinematic data were collected (100 Hz, 3 seconds), and mixed-design analyses of variance (group, speed) were performed with movement time, movement amplitude, acceleration time, and model-observed similarities as dependent variables. Nonparametric tests were performed for number of velocity peaks. Results Nonoperated and postsurgery patients showed similarities at preferred and faster movement speeds but not at slower speed. Postsurgery patients were closer to maximally smoothed motion and differed from healthy controls mainly during slow arm movements (closer to maximal smoothness, larger movement amplitude, shorter movement time, and lower number of peaks; i.e., less movement fragmentation). Conclusions Arm kinematic analyses suggest that open surgery stabilizes the shoulder but does not necessarily restore normal movement quality. Patients with recurrent anterior shoulder instability (RASI) seem to implement a “safe” but nonadaptive mode of action whereby preplanned stereotypical movements may be executed without depending on feedback. Rehabilitation of RASI patients should focus on restoring feedback-based movement control. Clinical assessment of RASI patients should include higher order kinematic descriptors. |
||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor  |
|||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 74 | |||
| Permanent link to this record | |||||
| Author | Uri, O.; Pritsch, M.; Oran, A.; Liebermann, D.G. | ||||
| Title | Upper limb kinematics after arthroscopic and open shoulder stabilization | Type | Journal Article | ||
| Year | 2014 | Publication | Journal of Shoulder and Elbow Surgery | Abbreviated Journal | Journal of Shoulder and Elbow Surgery |
| Volume | Issue | Pages | |||
| Keywords | |||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor |
|||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1058-2746 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 75 | |||
| Permanent link to this record | |||||
| Author | Noy, L.; Alon, U.; Friedman, J. | ||||
| Title | Corrective jitter motion shows similar individual frequencies for the arm and the finger | Type | Journal Article | ||
| Year | 2015 | Publication | Experimental Brain Research | Abbreviated Journal | Exp Brain Res |
| Volume | 233 | Issue | 4 | Pages | 1307-1320 |
| Keywords | |||||
| Abstract | A characteristic of visuomotor tracking of non-regular oscillating stimuli are high-frequency jittery corrective motions, oscillating around the tracked stimuli. However, the properties of these corrective jitter responses are not well understood. For example, does the jitter response show an idiosyncratic signature? What is the relationship between stimuli properties and jitter properties? Is the jitter response similar across effectors with different inertial properties? To answer these questions, we measured participants' jitter frequencies in two tracking tasks in the arm and the finger. Thirty participants tracked the same set of eleven non-regular oscillating stimuli, vertically moving on a screen, once with forward-backward arm movements (holding a tablet stylus) and once with upward-downward index finger movements (with a motion tracker attached). Participants' jitter frequencies and tracking errors varied systematically as a function of stimuli frequency and amplitude. Additionally, there were clear individual differences in average jitter frequencies between participants, ranging from 0.7 to 1.15 Hz, similar to values reported previously. A comparison of individual jitter frequencies in the two tasks showed a strong correlation between participants' jitter frequencies in the finger and the arm, despite the very different inertial properties of the two effectors. This result suggests that the corrective jitter response stems from common neural processes. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor |
|||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0014-4819 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:25630905 | Approved | no | ||
| Call Number | Serial | 76 | |||
| Permanent link to this record | |||||
| Author | Portnoy, S.; Rosenberg, L.; Alazraki, T.; Elyakim, E.; Friedman, J. | ||||
| Title | Differences in Muscle Activity Patterns and Graphical Product Quality in Children Copying and Tracing Activities on Horizontal or Vertical Surfaces | Type | Journal Article | ||
| Year | 2015 | Publication | Journal of Electromyography and Kinesiology | Abbreviated Journal | Journal of Electromyography and Kinesiology |
| Volume | 25 | Issue | 3 | Pages | 540�547 |
| Keywords | Motor equivalence; Electromyography; Tablet; Occupational Therapy; Muscle fatigue; Motor control | ||||
| Abstract | The observation that a given task, e.g. producing a signature, looks similar when created by different motor commands and different muscles groups is known as motor equivalence. Relatively little data exists regarding the characteristics of motor equivalence in children. In this study, we compared the level of performance when performing a tracing task and copying figures in two common postures: while sitting at a desk and while standing in front of a wall, among preschool children. In addition, we compared muscle activity patterns in both postures. Specifically, we compared the movements of 35 five- to six-year old children, recording the same movements of copying figures and path tracing on an electronic tablet in both a horizontal orientation, while sitting, and a vertical orientation, while standing. Different muscle activation patterns were observed between the postures, however no significant difference in the performance level was found, providing evidence of motor equivalence at this young age. The study presents a straightforward method of assessing motor equivalence that can be extended to other stages of development as well as motor disorders. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor |
|||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1050-6411 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 77 | |||
| Permanent link to this record | |||||
| Author | Zopf, R.; Friedman, J.; Williams, M.A. | ||||
| Title | The plausibility of visual information for hand ownership modulates multisensory synchrony perception | Type | Journal Article | ||
| Year | 2015 | Publication | Abbreviated Journal | Experimental Brain Research | |
| Volume | 233 | Issue | 8 | Pages | 2311-2321 |
| Keywords | Multisensory perception; Temporal synchrony perception; Virtual hand; Body representations; Body ownership; Sensory predictions | ||||
| Abstract | We are frequently changing the position of our bodies and body parts within complex environments. How does the brain keep track of one’s own body? Current models of body ownership state that visual body ownership cues such as viewed object form and orientation are combined with multisensory information to correctly identify one’s own body, estimate its current location and evoke an experience of body ownership. Within this framework, it may be possible that the brain relies on a separate perceptual analysis of body ownership cues (e.g. form, orientation, multisensory synchrony). Alternatively, these cues may interact in earlier stages of perceptual processing—visually derived body form and orientation cues may, for example, directly modulate temporal synchrony perception. The aim of the present study was to distinguish between these two alternatives. We employed a virtual hand set-up and psychophysical methods. In a two-interval force-choice task, participants were asked to detect temporal delays between executed index finger movements and observed movements. We found that body-specifying cues interact in perceptual processing. Specifically, we show that plausible visual information (both form and orientation) for one’s own body led to significantly better detection performance for small multisensory asynchronies compared to implausible visual information. We suggest that this perceptual modulation when visual information plausible for one’s own body is present is a consequence of body-specific sensory predictions. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Springer Berlin Heidelberg | Place of Publication | Editor |
||
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0014-4819 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 78 | |||
| Permanent link to this record | |||||