Once home, I googled autism awareness, bumper sticker, and entered a whole world of autism products. Bumper stickers, of course. But also tee shirts, jewelry, stickers (I am someone with autism), mugs. Eventually, I exited even more perplexed than I entered.
In general, the digestive system is controlled by both nerves and hormones. The nerves that control digestion are in the submucosa layer of the tissue and in between the muscle layers of the walls of the organ.
It is the medulla oblongata that controls swallowing. It also  controls functions such as breathing and blood pressure. It is the  lower portion of the brainstem.