Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Thumb motor performance varies by movement orientation, direction, and device size during single-handed mobile phone use.

Authors
Trudeau-MB; Udtamadilok-T; Karlson-AK; Dennerlein-JT
Source
Hum Factors 2012 Feb; 54(1):52-59
NIOSHTIC No.
20040482
Abstract
OBJECTIVE: The aim of this study was to determine if thumb motor performance metrics varied by movement orientation, direction, and device size during single-handed use of a mobile phone device. BACKGROUND: With the increased use of mobile phones, understanding how design factors affect and improve performance can provide better design guidelines. METHOD: A repeated measures laboratory experiment of 20 right-handed participants measured the thumb tip's 3-D position relative to a phone during reciprocal tapping tasks across four phone designs and four thumb tip movement orientations. Each movement orientation included two movement directions: an "outward" direction consisting in CMC (carpometacarpal) joint flexion or abduction movements and an "inward" direction consisting in CMC joint extension or adduction movements. Calculated metrics of the thumb's motor performance were Fitts' effective width and index of performance. RESULTS: Index of performance varied significantly across phones, with performance being generally better for the smaller devices. Performance was also significantly higher for adduction-abduction movement orientations compared to flexion-extension, and for "outward" compared to "inward" movement directions. CONCLUSION: For single-handed device use, adduction-abduction-type movements on smaller phones lead to better thumb performance. APPLICATION: The results from this study can be used to design new mobile phone devices and keypad interfaces that optimize specific thumb motions to improve the user-interface experience during single-handed use.
Keywords
Biomechanics; Muscle-function; Musculoskeletal-system; Physical-capacity; Physical-reactions; Physiological-factors; Physiological-function; Author Keywords: biomechanics; Fitts' law; motor control; texting; keypad interface
Contact
Jack T. Dennerlein, Harvard School of Public Health, Department of Environmental Health, 401 Park Drive, Room 404L, Boston, MA 02215
CODEN
HUFAA6
Publication Date
20120201
Document Type
Journal Article
Email Address
jax@hsph.harvard.edu
Funding Type
Grant
Fiscal Year
2012
NTIS Accession No.
NTIS Price
Identifying No.
Grant-Number-R01-OH-008373; Grant-Number-T42-OH-008416; B03282012
Issue of Publication
1
ISSN
0018-7208
Source Name
Human Factors
State
MA; WA
Performing Organization
Harvard University School of Public Health
TOP