## Abstract A pairedโstimuli paradigm combined with fMRI was utilized to study the effect of gradient acoustic noise on fMRI response in the human primary visual cortex (V1) in terms of the auditoryโvisual crossโmodal neural interaction. The gradient noise generated during the fMRI acquisition was
Effects of the acoustic noise of the gradient systems on fMRI: A study on auditory, motor, and visual cortices
โ Scribed by Zang-Hee Cho; Soon-Chul Chung; Dae-Woon Lim; Edward K. Wong
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 610 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0740-3194
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
MR acoustic, or sound, noise due to gradient pulsing has been one of the problems in MRI, both in patient scanning as well as in many areas of psychiatric and neuroscience research, such as brain fMRI. Especially in brain fMRI, sound noise is one of the serious noise sources that obscures the small signals obtainable from the subtle changes occurring in oxygenation status in the cortex and blood capillaries. Therefore, we have studied the effects of acoustic, or sound, noise arising in fMR imaging of the auditory, motor, and visual cortices. The results show that the effects of acoustic noise on motor and visual responses are opposite. That is, for motor activity, there is an increased total motor activation, whereas for visual stimulation, the corresponding (visual) cortical activity is diminished substantially when the subject is exposed to a loud acoustic sound. Although the current observations are preliminary and require more experimental confirmation, it seems that the observed acousticโnoise effects on brain functions, such as in the motor and visual cortices, are new observations and could have significant consequences in data observation and interpretation in future fMRI studies.
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