Habituation of the BOLD response in fMRI of the human auditory and visual cortex
Elliott M, Bloy L, Hulvershorn J
University of Pennsylvania
An event-related fMRI study which activated the primary auditory and visual cortices was examined for trends in habituation of the BOLD hemodynamic response during the course of the experiment. In both functional regions, the average time-to-peak of the BOLD response decreased significantly with increasing stimulus count. Converely, the amplitude of the BOLD response increased during the experiment, though statistical significance was only observed in the visual cortex. Unlike other studies which have shown reduced and delayed responses (habituation) to successive lengthy stimuli, this result reveals that brief event-related stimuli produced a larger and faster response, consistent with a neuro-vascular priming effect.