@koantig Maia Szalavitz goes into this in Unbroken Brain, though I couldn’t find the marshmallow test specifically in the index. https://www.amazon.com/Unbroken-Brain-Revolutionary-Understanding-Addiction/dp/1250116449/ref=sr_1_1?ie=UTF8&qid=1528044867&sr=8-1&keywords=unbroken+brain+by+maia+szalavitz She talks a lot about how childhood trauma can shape tendencies towards addictive behavior.