Effects of long-term potentiation in the human visual cortex: a functional magnetic resonance imaging study

Applying functional magnetic resonance imaging techniques, hemodynamic responses elicited by slowly flashing checkerboards (0.25 Hz) were measured both before and after a block of rapidly presented checkerboards (9 Hz - a 'photic tetanus') was delivered. It has been shown previously, using electroencephelography, that this photic tetanus potentiates components of the visual-evoked potential. In the present study, hemodynamic responses in the extrastriate visual cortex were significantly increased to checkerboards presented at a low frequency after the administration of the photic tetanus. These results support the idea that long-term potentiation can be demonstrated non-invasively within the human visual cortex and provide evidence that the plastic changes are localized within the secondary visual cortex. NeuroReport 16:1977-1980 (c) 2005 Lippincott Williams & Wilkins.