|
Records |
Links |
|
Author |
Friedman, J; Latash, M.L.; Zatsiorsky, V.M. |
|
|
Title |
Directional variability of the isometric force vector produced by the hand in multi-joint planar tasks |
Type |
Journal Article |
|
Year |
2011 |
Publication |
Journal of Motor Behavior |
Abbreviated Journal |
|
|
|
Volume |
43 |
Issue |
6 |
Pages |
451-463 |
|
|
Keywords |
|
|
|
Abstract |
Numerous studies have examined control of force magnitude, but relatively little research has considered force direction control. In this study, subjects applied isometric forces to a handle and we compared within-trial variability when producing force in different directions. The standard deviation (SD) of the force parallel to the prescribed direction of force production increased linearly with the targeted force level, as did the SD of the force perpendicular to the instructed direction. In contrast, the SD of the angle of force production decreased with increased force level. In the four (of eight) instructed force directions where the endpoint force was generated due to a joint torque in only one joint (either the shoulder or elbow) the principal component axes in force space were well aligned with the prescribed direction of force production. In the other directions, the variance was approximately equal along the two force axes. The variance explained by the first principal component was significantly larger in torque space compared to the force space, and mostly corresponded to positive correlation between the joint torques. Such coordinated changes suggest that the torque variability was mainly due to the variability of the common drive to the muscles serving two joints, although this statement needs to be supported by direct studies of muscle activation in the future. |
|
|
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 |
Penn State @ write.to.jason @ |
Serial |
26 |
|
Permanent link to this record |
|
|
|
|
Author |
Awasthi, Bhuvanesh; Friedman, Jason; Williams, Mark A |
|
|
Title |
Reach Trajectories Reveal Delayed Processing of Low Spatial Frequency Faces in Developmental Prosopagnosia |
Type |
Journal Article |
|
Year |
2012 |
Publication |
Cognitive Neuroscience |
Abbreviated Journal |
|
|
|
Volume |
3 |
Issue |
2 |
Pages |
120-130 |
|
|
Keywords |
|
|
|
Abstract |
Developmental prosopagnosia (DP) is characterized by a selective deficit in face recognition despite normal cognitive and neurological functioning. Previous research has established configural processing deficits in DP subjects. Low spatial frequency (LSF) information subserves configural face processing. Using hybrid stimuli, here we examined the evolution of perceptual dynamics and integration of LSF information by DP subjects while they pointed to high spatial frequency (HSF) face targets. Permutation analysis revealed a 230-ms delay in LSF processing by DP subjects as compared to controls. This delayed processing is likely to contribute to the difficulties associated with face recognition in DP subjects and is reflective of their alleged reliance on local rather than global features in face perception. These results suggest that quick and efficient processing of LSF information is critical for the development of normal face perception. |
|
|
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 |
Penn State @ write.to.jason @ |
Serial |
27 |
|
Permanent link to this record |
|
|
|
|
Author |
Flash, T.; Richardson, M. E.; Handzel, A. A.; Liebermann, D. G. |
|
|
Title |
Computational Models and Geometric Approaches in Arm Trajectory Control Studies |
Type |
Book Chapter |
|
Year |
2003 |
Publication |
Progress in Motor Control III: From Basic Science to Applications |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
|
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Human Kinetics |
Place of Publication |
Champaign, Il |
Editor |
M. L. Latash; M. F. Levin |
|
|
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 |
44 |
|
Permanent link to this record |
|
|
|
|
Author |
Liebermann, D.G.; Franks, I. M. |
|
|
Title |
The use of feedback-based technologies in skill acquisition |
Type |
Book Chapter |
|
Year |
2004 |
Publication |
Notational analysis of Sport and Coaching Science |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
|
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
E & FN Spon Pub |
Place of Publication |
|
Editor |
M. Hughes; I.M. Franks |
|
|
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 |
45 |
|
Permanent link to this record |
|
|
|
|
Author |
Carmeli E.; Liebermann, D.G. |
|
|
Title |
The Function of the Aging Hand |
Type |
Book Chapter |
|
Year |
2007 |
Publication |
The Geriatric Rehabilitation Manual |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
|
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier |
Place of Publication |
NY |
Editor |
T. L. Kauffman; M. Moran; J. Barr |
|
|
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 |
46 |
|
Permanent link to this record |