Open AccessThis article is
- freely available
A Low-Cost, Computer-Interfaced Drawing Pad for fMRI Studies of Dysgraphia and Dyslexia
Instrument Development Lab, Center on Human Development and Disability, University of Washington, Seattle, WA 98195, USA
Integrated Brain Imaging Center, Department of Radiology, University of Washington, Seattle, WA 98195, USA
* Author to whom correspondence should be addressed.
Received: 20 March 2013; in revised form: 10 April 2013 / Accepted: 11 April 2013 / Published: 17 April 2013
Abstract: We have developed a pen and writing tablet for use by subjects during fMRI scanning. The pen consists of two jacketed, multi-mode optical fibers routed to the tip of a hollowed-out ball-point pen. The pen has been further modified by addition of a plastic plate to maintain a perpendicular pen-tablet orientation. The tablet is simply a non-metallic frame holding a paper print of continuously varying color gradients. The optical fibers are routed out of the MRI bore to a light-tight box in an adjacent control room. Within the box, light from a high intensity LED is coupled into one of the fibers, while the other fiber abuts a color sensor. Light from the LED exits the pen tip, illuminating a small spot on the tablet, and the resulting reflected light is routed to the color sensor. Given a lookup table of position for each color on the tablet, the coordinates of the pen on the tablet may be displayed and digitized in real-time. While simple and inexpensive, the system achieves sufficient resolution to grade writing tasks testing dysgraphic and dyslexic phenomena.
Keywords: fMRI; MRI-compatible; dygraphia; dyslexia; lexical; handwriting; LabVIEW
Citations to this Article
Cite This Article
MDPI and ACS Style
Reitz, F.; Richards, T.; Wu, K.; Boord, P.; Askren, M.; Lewis, T.; Berninger, V. A Low-Cost, Computer-Interfaced Drawing Pad for fMRI Studies of Dysgraphia and Dyslexia. Sensors 2013, 13, 5099-5108.
Reitz F, Richards T, Wu K, Boord P, Askren M, Lewis T, Berninger V. A Low-Cost, Computer-Interfaced Drawing Pad for fMRI Studies of Dysgraphia and Dyslexia. Sensors. 2013; 13(4):5099-5108.
Reitz, Frederick; Richards, Todd; Wu, Kelvin; Boord, Peter; Askren, Mary; Lewis, Thomas; Berninger, Virginia. 2013. "A Low-Cost, Computer-Interfaced Drawing Pad for fMRI Studies of Dysgraphia and Dyslexia." Sensors 13, no. 4: 5099-5108.