Figure 5.

A, Visualization of the impact of spatial resolution, localized shimming, and smoothing on the global mean BOLD signal intensity and tSNR. The mean BOLD response is increased in the neighborhood of the NFA (approximate NFA location is marked by black circles) by the higher spatial resolution. The tSNR is generally higher with the lower resolution; however, this effect is not as severe near the NFA. Smoothing increases the tSNR, particularly in the high-resolution images, so that, after preprocessing the tSNR near the NFA is largest in the high-resolution images. Images were created using Caret (Van Essen et al., 2001). B, Example of the position of the recorded volume (yellow box) and of the area where the localized shimming was performed (green box).