J Korean Soc Magn Reson Med.  1999 Mar;3(1):41-46.

fMRI of Visual and Motor Stimuli: Difference of Total Activation Depends on Stimulation Paradigm

• Chung SC
• Song IC
• Chang KH
• YU BK
• Mun CW
• Cho ZH

Abstract

PURPOSE
To investigate the difference of total activation in visual area, motor area, and cerebellum according to the stimulation paradigm.
MATERIALS AND METHODS
Functional MR imaging was performed in 5 healthy volunteers with visual and motor activity using EPI technique. LED and Checker-Board stimulation were performed for visual activity. Thumb motion and Finger tapping were performed for motor and cerebellum activity. Stimulus timing was 60sec. off, 120sec. on, 60sec. off. Data processing was carried out by using the cross-correlation method for each pixel. Each pixel was then selected and assumed activated if the correlation coefficient was equal or large than a threshold value. Time course data was obtained by calculating the total activation which was defined as the number of activated pixels x averaged pixel intensity. RESULT: In the case of visual activity with LED stimulation, we found increased total activity of more than 100% compared with Checker-Board stimulation. In the case of motor area and cerebellum with Finger tapping stimulation, we found increased total activity of more than 100% and 150%, respectively compared with Thumb motion stimulation.
CONCLUSION
We found the difference of total activation in visual area, motor area and cerebellum according to the stimulation paradigm.

Keyword

Brain; function; Brain; MR; stimulation paradigm

MeSH Terms

Brain
Cerebellum
Fingers
Healthy Volunteers
Magnetic Resonance Imaging*
Motor Activity
Thumb