Functional magnetic resonance imaging mirrors recovery of visual perception after repetitive tachistoscopic stimulation in patients with partial cortical blindness.
We investigated three patients with partial cortical blindness after brain injury by means of functional magnetic resonance imaging (fMRI) before and after the application of a daily visual stimulation-therapy over a period of 6 months. Before therapy, fMRI data showed a severely reduced blood-oxygen-level-dependent (BOLD) signal in primary visual cortex when compared to healthy volunteers. Following several months of rehabilitative therapy a neuropsychological improvement of visual functions was accompanied by an increase in BOLD signal of residual perilesional regions whereas fMRI data of the control group remained unchanged. A high capacity of functional recovery and synaptic plasticity of surviving perilesional neuronal structures of primary visual cortex followed by an increased input into post-connected visual areas can be discussed as a basis for the reoccurrence of visual functions.
Pleger
Burkhard
B
Department of Neurology, Ruhr-University Bochum, BG-Kliniken Bergmannsheil, Buerkle-de-la-Camp-Platz 1, D-44789 Bochum, Germany. burkhard.v.pleger@ruhr-uni-bochum.de
Foerster
Ann-Freya
AF
Widdig
Walter
W
Henschel
Markus
M
Nicolas
Volkmar
V
Jansen
Andreas
A
Frank
Andreas
A
Knecht
Stefan
S
Schwenkreis
Peter
P
Tegenthoff
Martin
M
D000328:Adult; D019575:Blindness, Cortical / Q000503:physiopathology / Q000628:therapy*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation; D020127:Recovery of Function; D014793:Visual Cortex / Q000503:physiopathology*; D014796:Visual Perception