Snakes and MRI machines figure together in several scientific studies. Here are two of them:
“Contour extraction from cardiac MRI studies using snakes,” S. Ranganath, IEEE Trans Med Imaging. 1995;14(2):328-38.
and
“Fear Thou Not: Activity of Frontal and Temporal Circuits in Moments of Real-Life Courage,” Uri Nili, Hagar Goldberg, Abraham Weizman and Yadin Dudai, Neuron, Volume 66, Issue 6, 949-962, 24 June 2010. The authors, at the Weizmann Institute, explain (and also present video):
“In this study, volunteers who fear snakes had to bring a live snake into close proximity with their heads while their brains were scanned using functional magnetic resonance imaging (fMRI). Bringing the snake closer was associated with a dissociation between subjective fear and somatic arousal.”
BONUS: Snakes on a plane: