Detectability of the BOLD signal
نویسندگان
چکیده
Introduction The BOLD signal is a weak signal, and hence if no BOLD signal is found in an area this does not automatically mean there is no neural activity in that area. Signal dropout, artifacts, instability, physiological noise, RF-coil inhomogeneity etc. can all reduce the SNR locally leading to decreased detectability of the BOLD signal. Here we illustrate that calculation of the spatial distribution of the detection thresholds allows us to assign a degree of confidence to the activations as well as identify areas where detectability of functional activation is compromised.
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