Years later Dr. Mischel reached out to the participants of his study who were then in their 40s. He found that those who showed less self-control by taking the single marshmallow in the initial study were more likely to develop problems with relationships, stress, and drug abuse later in life. Dr. Mischel carried out the experiment again with the same participants in order to see which parts of the brain were active during the process of self-control. The participants received scans through M.R.I to show brain activity. The results showed that those who exhibited lower levels of self-control had higher brain activity in the ventral striatum, the area that deals with positive rewards.