Spontaneous fluctuations of BOLD signal: effect of anesthesia and functional significance
نویسندگان
چکیده
INTRODUCTION Spontaneous fluctuations in BOLD signal are used for functional connectivity [1]. It has been suggested that these spontaneous fluctuations may influence trial-to-trial variability of the evoked BOLD response [2]. Taken together, these studies suggest that the amplitude of the spontaneous fluctuation has significance for the strength of the functional connectivity (between symmetric points in two hemispheres) and the phase of the BOLD signal fluctuation just preceding the stimulus can affect the trial-to-trial variability of the evoked BOLD response. We measured the BOLD signal spontaneous fluctuations and whisker functional responses in rat cortex with two slightly different baseline states (lightly anesthetized and awakened animals) to investigate these suggestions.
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