Dopamine is a pleasure chemical. Technically, it is a hormone and a neurotransmitter.
Research shows if you do an activity every day for three weeks, thereafter your brain releases dopamine each time you continue repeating the activity.
A college friend, whose father was a psychologist, used to say you create a new habit by doing something 21 times in a row. I wondered if his assertion came from legitimate research, or if it was a type of declaration or placebo effect, i.e. say it is so, and it will be so. Obviously, his assertion came from legit research.
This stuff is important to know. It helps us understand the process of both forming and breaking habits. Knowledge is power.
Jann, of Second Life:
That pesky brain of yours was set-up to develop habits so that it can conserve energy. The brain spends its energy on breathing, coordinated motion, and actually thinking. Our little 3lb brains revert to habits when given the chance because habits require less energy than change. How do we develop habits? Rebecca and her brain scientist friends explain: It's dopamine. You see, you do something you like or gives you pleasure ... and you get a dopamine surge. Rebecca explains that some of that dopamine travels to the area of your brain where memories are formed and creates a memory connecting that thing that gave you pleasure with a reward. It becomes "salient." It doesn't matter whether its good for you. The short story, the more you do it, the more the frontal lobe fires until after a certain point, the brain makes it a habit . The further problem with this is that dopamine also controls desire, decision making and motivation. Beginning to see the big picture now? Eventually, the brain will release the dopamine when in the environment of the pleasure or if something reminds it of that thing. Then you get that "Jonesing" feeling.