Visual stimulus presentation using fiber optics in the MRI scanner

• Published in: Journal of neuroscience methods Vol. 169; no. 1; pp. 76 - 83
• Main Authors: Huang, Ruey-Song, Sereno, Martin I.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 30.03.2008
• Subjects: 3-D stimuli; Algorithms; Brain Mapping - instrumentation; Brain Mapping - methods; Electronics - instrumentation; Electronics - methods; Face - physiology; Fiber Optic Technology - instrumentation; Fiber Optic Technology - methods; Fiber optics; fMRI; Humans; Image Processing, Computer-Assisted - instrumentation; Image Processing, Computer-Assisted - methods; Magnetic Resonance Imaging - instrumentation; Magnetic Resonance Imaging - methods; Magnetics - instrumentation; Near-face space; Neuropsychological Tests; Optical Fibers; Orientation - physiology; Peripersonal space; Photic Stimulation - instrumentation; Photic Stimulation - methods; Psychomotor Performance - physiology; Saccades - physiology; Software; Space Perception - physiology; Visual Cortex - anatomy & histology; Visual Cortex - physiology; Visual Fields - physiology; Visual Perception - physiology; fMRI; 3-D stimuli; Peripersonal space; Near-face space; Fiber optics
• ISSN: 0165-0270; 1872-678X
• DOI: 10.1016/j.jneumeth.2007.11.024

Imaging the neural basis of visuomotor actions using fMRI is a topic of increasing interest in the field of cognitive neuroscience. One challenge is to present realistic three-dimensional (3-D) stimuli in the subject's peripersonal space inside the MRI scanner. The stimulus generating apparatus must be compatible with strong magnetic fields and must not interfere with image acquisition. Virtual 3-D stimuli can be generated with a stereo image pair projected onto screens or via binocular goggles. Here, we describe designs and implementations for automatically presenting physical 3-D stimuli (point-light targets) in peripersonal and near-face space using fiber optics in the MRI scanner. The feasibility of fiber-optic based displays was demonstrated in two experiments. The first presented a point-light array along a slanted surface near the body, and the second presented multiple point-light targets around the face. Stimuli were presented using phase-encoded paradigms in both experiments. The results suggest that fiber-optic based displays can be a complementary approach for visual stimulus presentation in the MRI scanner.