it has been previously recommended that a -30 angle (in reference to AC-PC) helps reduce signal artifact and signal loss i ventral prefrontal cortex and in other artifact prone regions like the amygdala.

[reference: Deichmann et al., 2003. Optimized EPI for fMRI studies of the orbitofrontal cortex.]

i have collected some pilot data and it does appear that signal quality is better with the -30 angle.

i'm curious if there are any concerns with coregistration to a structural scan or template. i guess i'm unfamiliar with how 3dAllineate works and how it would handle a scan that is not collected as straight axial.

example image can be found here (note that because of the angle, a portion of posterior parietal cortex is cut off. this area is not of interest but again i'm not sure if this impacts coregistration quality).

[www.dropbox.com]


thank you,

jatin