Duhigg begins Chapter 1 with a case study. In 1993, Professor Larry Squire at the University of California, San Diego, began to study a man named Eugene Pauly, a 71-year-old man who had been seriously affected by an earlier case of viral encephalitis. The virus harmed the medial temporal lobe in Eugene’s brain, meaning his short-term and long-term memory were almost totally gone. What made Eugene’s case especially interesting for Squire and other researchers was the patient’s ability to slowly form new habits despite the fact that his damaged brain did not hold memories.

Squire made a major contribution to memory research with Eugene when he proved that new habits can be performed even without the active knowledge of the person. Habits, Duhigg writes, “emerge without our permission” (26). Squire’s findings joined other scientific research in the 1990s coming from the Massachusetts Institute of Technology, where scientists began to analyze where in the brain habits are formed. They determined that the basal ganglia, a small ball in the base of the brain near the spinal column, controls habit formation and other automatic behaviors, such as fight or flight. Using memory experiments on rats, scientists determined that the basal ganglia “stored habits even while the rest of the brain went to sleep” (15).