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Fig 1. The color overlays represent regions that have sufficient levels of confidence to interpret the brain activation map. The 3 different rows represent different methods and conditions. The first row shows the SIM method based solely on the static image intensity. The second and third rows are based on a statistical model, BOLD signal intensity change and the temporal SNR. The second row indicates where it is possible to detect a 1% or greater BOLD signal intensity change. The third row represents where a 0.5% or greater BOLD signal intensity change can be detected. Smaller BOLD changes are likely to take place in clinical patients because of abnormal physiology and poor performance because of the presence of a lesion. It is clear that the temporal stability of these data are not sufficient to detect small BOLD changes.