Article

Imaging the amygdala with functional MRI is confounded by multiple averse
factors, notably signal dropouts due to magnetic inhomogeneity and low
signal-to-noise ratio, making it difficult to obtain consistent activation
patterns in this region. However, even when consistent signal changes are
identified, they are likely to be due to nearby vessels, most notably the basal
vein of rosenthal (BVR). Using an accelerated fMRI sequence with a high temporal
resolution (TR = 333 ms) combined with susceptibility-weighted imaging, we show
how signal changes in the amygdala region can be related to a venous origin. This
finding is confirmed here in both a conventional fMRI dataset (TR = 2000 ms) as
well as in information of meta-analyses, implying that "amygdala activations"
reported in typical fMRI studies are likely confounded by signals originating in
the BVR rather than in the amygdala itself, thus raising concerns about many
conclusions on the functioning of the amygdala that rely on fMRI evidence alone.

Langue : ANGLAIS

Tiré à part : OUI