Morgan comes from a very superstitious family. Her mother grew up in Northern Virginia (with some time spent in Washingon D.C.) and her father grew up in Pennsylvania. Morgan herself was born in Montclair, New Jersey. Her family then moved to Arizona, where she spent her childhood before moving to Las Vegas as a teenager. Her family has very strong belief in the supernatural and she shared with me some of their superstitions.

“Hold your feet up in the air while riding over a bridge or train tracks; press your hands against the ceiling when traveling under them, or through a tunnel. (And hold your breath while inside a tunnel!) – The first ones were made up by my mother’s best friend when they were children; the logic was that it’d keep the bridge from collapsing, etc. My youngest sister has been trying to popularize the idea of pressing your hands against the side of the car if a train passes by that side, to keep the train from toppling over, but it hasn’t been catching on.”
The superstitions about holding up the bridge or keeping the train on its tracks are definitely examples of magical thinking, more specifically Homeopathic (sympathetic) magic, which operates on the principal that “like produces like.” In this case, Morgan’s family uses a symbolic representation of an action to try and affect the entire situation. Potentially, the reason her sister is having trouble getting the new tradition to catch on is because magical thinking in the United States has waned as modernity progresses (probably, in this particular case, thanks to advances in engineering and architecture that have all but removed the threat of an imminent structural collapse).
The holding one’s breath inside a tunnel is a custom that appears in some form or another throughout most of the United States. Sometimes the belief is that if the person makes it to the end of the tunnel, he or she has the right to make a wish (like passing a challenge and receiving a reward). In this case, the breath-holding seems to be a in the interest of protection, as though the tension in one’s lungs and face could carry over and strengthen the tunnel. (This would not the be first breath-holding superstition that relates to protection; traditionally- particularly in the American South- one holds one’s breath while passing by a graveyard both to pay respect to those who do not have breath themselves and to avoid breathing in spirits with malicious intent.)