|   | 
Details
   web
Records
Author Friedman, Jason; Flash, Tamar
Title Trajectory of the index finger during grasping Type Journal Article
Year 2009 Publication Experimental Brain Research Abbreviated Journal Exp Brain Res
Volume 196 Issue 4 Pages 497-509
Keywords
Abstract The trajectory of the index finger during grasping movements was compared to the trajectories predicted by three optimization-based models. The three models consisted of minimizing the integral of the weighted squared joint derivatives along the path (inertia-like cost), minimizing torque change, and minimizing angular jerk. Of the three models, it was observed that the path of the fingertip and the joint trajectories, were best described by the minimum angular jerk model. This model, which does not take into account the dynamics of the finger, performed equally well when the inertia of the finger was altered by adding a 20 g weight to the medial phalange. Thus, for the finger, it appears that trajectories are planned based primarily on kinematic considerations at a joint level.
Address Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, Israel, write.to.jason@gmail.com
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 (down) 1432-1106 ISBN Medium
Area Expedition Conference
Notes PMID:19521692 Approved no
Call Number Penn State @ write.to.jason @ Serial 17
Permanent link to this record
 

 
Author Shaklai, S.; Mimouni-Bloch, A.; Levin, M.; Friedman, J.
Title Development of finger force coordination in children Type Journal Article
Year 2017 Publication Experimental Brain Research Abbreviated Journal
Volume 235 Issue 12 Pages 3709–3720
Keywords
Abstract Coordination is often observed as body parts moving together. However, when producing force with multiple fingers, the optimal coordination is not to produce similar forces with each finger, but rather for each finger to correct mistakes of other fingers. In this study, we aim to determine whether and how this skill develops in children aged 4-12 years. We measured this sort of coordination using the uncontrolled manifold hypothesis (UCM). We recorded finger forces produced by 60 typically developing children aged between 4 and 12 years in a finger-pressing task. The children controlled the height of an object on a screen by the total amount of force they produced on force sensors. We found that the synergy index, a measure of the relationship between “good” and “bad” variance, increased linearly as a function of age. This improvement was achieved by a selective reduction in “bad” variance rather than an increase in “good” variance. We did not observe differences between males and females, and the synergy index was not able to predict outcomes of upper limb behavioral tests after controlling for age. As children develop between the ages of 4 and 12 years, their ability to produce negative covariation between their finger forces improves, likely related to their improved ability to perform dexterous tasks.
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 (down) 1432-1106 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Shaklai2017 Serial 86
Permanent link to this record
 

 
Author Krasovsky, T.; Weiss, P.L.; Zuckerman, O.; Bar, A.; Keren-Capelovitch, T.; Friedman, J.
Title DataSpoon: Validation of an Instrumented Spoon for Assessment of Self-Feeding Type Journal Article
Year 2020 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)
Volume 20 Issue 7 Pages
Keywords concurrent validity; feasibility; kinematics; outcome assessment; rehabilitation
Abstract Clinically feasible assessment of self-feeding is important for adults and children with motor impairments such as stroke or cerebral palsy. However, no validated assessment tool for self-feeding kinematics exists. This work presents an initial validation of an instrumented spoon (DataSpoon) developed as an evaluation tool for self-feeding kinematics. Ten young, healthy adults (three male; age 27.2 +/- 6.6 years) used DataSpoon at three movement speeds (slow, comfortable, fast) and with three different grips: “natural”, power and rotated power grip. Movement kinematics were recorded concurrently using DataSpoon and a magnetic motion capture system (trakSTAR). Eating events were automatically identified for both systems and kinematic measures were extracted from yaw, pitch and roll (YPR) data as well as from acceleration and tangential velocity profiles. Two-way, mixed model Intraclass correlation coefficients (ICC) and 95% limits of agreement (LOA) were computed to determine agreement between the systems for each kinematic variable. Most variables demonstrated fair to excellent agreement. Agreement for measures of duration, pitch and roll exceeded 0.8 (excellent agreement) for >80% of speed and grip conditions, whereas lower agreement (ICC < 0.46) was measured for tangential velocity and acceleration. A bias of 0.01-0.07 s (95% LOA [-0.54, 0.53] to [-0.63, 0.48]) was calculated for measures of duration. DataSpoon enables automatic detection of self-feeding using simple, affordable movement sensors. Using movement kinematics, variables associated with self-feeding can be identified and aid clinical reasoning for adults and children with motor impairments.
Address Department of Physical Therapy, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
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 (down) 1424-8220 ISBN Medium
Area Expedition Conference
Notes PMID:32283624; PMCID:PMC7180859 Approved no
Call Number Serial 104
Permanent link to this record
 

 
Author Melzer, I.; Liebermann, D.G.; Krasovsky, T.; Oddsson, L.I.E.
Title Cognitive load affects lower limb force-time relations during voluntary rapid stepping in healthy old and young adults Type Journal Article
Year 2010 Publication The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences Abbreviated Journal J Gerontol A Biol Sci Med Sci
Volume 65 Issue 4 Pages 400-406
Keywords *Accidental Falls; Adult; Aged; Aged, 80 and over; Aging/*physiology; Attention/physiology; Cognition/*physiology; Gait/*physiology; Humans; Postural Balance/*physiology; Reaction Time
Abstract BACKGROUND: Quick step execution may prevent falls when balance is lost; adding a concurrent task delays this function. We investigate whether push-off force-time relations during the execution of rapid voluntary stepping is affected by a secondary task in older and young adults. METHODS: Nineteen healthy older adults and 12 young adults performed rapid voluntary stepping under single- and dual-task conditions. Peak power, peak force, and time to peak force during preparatory and swing phases of stepping were extracted from center of pressure and ground reaction force data. RESULTS: For dual-task condition compared with single-task condition, older adults show a longer time to reach peak force during the preparation and swing phases compared with young adults (approximately 25% vs approximately 10%, respectively). Peak power and peak force were not affected by a concurrent attention-demanding task. CONCLUSION: Older adults have difficulty allocating sufficient attention for fast muscle recruitment when concurrently challenged by an attention-demanding task.
Address Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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 (down) 1079-5006 ISBN Medium
Area Expedition Conference
Notes PMID:19939911 Approved no
Call Number Serial 50
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 (down) 1058-2746 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 75
Permanent link to this record