Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-3-7
pubmed:abstractText
The complex dynamics of the human hand/arm system need to be precisely controlled to produce fine movements such as those found in handwriting. This study employs dynamical systems analysis techniques to further understand how this system is controlled when it is functioning well and when it is compromised through motor function degradation (e.g. from tremor). Seven people with and 16 people without multiple sclerosis (MS) participated in this study. Tremor was assessed using spirography with participants being separated into "tremor" (6 people with and 1 person without MS; 2 male, 5 female; age range 40-68) and control (1 person with and 15 people without MS; 5 male, 11 female, age range 18-59) groups. Participants wrote the pseudo-word "lanordam" six times on a digitizer, in a quiet as well as a noisy, mildly stressful environment. Velocity profiles of the pen tip for the best four trials were concatenated and analyzed to determine their dimensionality (a measure of the number of control variables) and Lyapunov exponents (a measure of predictability). Results indicate that the velocity profiles for people with tremor were lower dimensional and had less predictable dynamics than for controls, with no effect of sound condition. Interpreted in the context of related research, it was speculated that the lower dimensionality reflected the loss of control of variables related to the minimization of movement variability, resulting in less predictable movements.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0167-9457
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
91-110
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:12623182-Adult, pubmed-meshheading:12623182-Age Factors, pubmed-meshheading:12623182-Aged, pubmed-meshheading:12623182-Arousal, pubmed-meshheading:12623182-Attention, pubmed-meshheading:12623182-Biomechanics, pubmed-meshheading:12623182-Computer Graphics, pubmed-meshheading:12623182-Female, pubmed-meshheading:12623182-Handwriting, pubmed-meshheading:12623182-Humans, pubmed-meshheading:12623182-Joints, pubmed-meshheading:12623182-Male, pubmed-meshheading:12623182-Middle Aged, pubmed-meshheading:12623182-Multiple Sclerosis, pubmed-meshheading:12623182-Neural Networks (Computer), pubmed-meshheading:12623182-Neuromuscular Junction, pubmed-meshheading:12623182-Nonlinear Dynamics, pubmed-meshheading:12623182-Psychomotor Performance, pubmed-meshheading:12623182-Reference Values, pubmed-meshheading:12623182-Signal Processing, Computer-Assisted, pubmed-meshheading:12623182-Systems Analysis, pubmed-meshheading:12623182-Tremor
pubmed:year
2003
pubmed:articleTitle
The influence of motor system degradation on the control of handwriting movements: a dynamical systems analysis.
pubmed:affiliation
Motor Control Laboratory, Arizona State University, Tempe, AZ 85287-0404, USA. mitchell.longstaff@asu.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't