Functional MRI in feigned visual loss

Abstract

This single-subject study studied the ability of functional magnetic resonance imaging (fMRI) to discern normal visual condition compared to feigned visual loss and induced-refractive blur condition. Under the normal binocular vision condition, activation of the parieto-occipital area reflected normal patterns of blood oxygenation level-dependent (BOLD) signals in the visual pathway. During the feigned/functional visual loss and refractive-induced blur condition, there was hypoactivation in the parieto-occipital visual pathway. This study showed that the subject could strongly influence the fMRI results, thus, further investigation and protocol refinement are needed to maximize the ability of fMRI to reliably serve as a clinical diagnostic tool in individual functional patients.