If you want to form good habits -- like going to the gym and eating healthy -- then you need to train your brain by repeating actions until they stick a new study suggests. The researchers have created a model which shows that forming good (and bad) habits depends more on how often you perform an action than on how much satisfaction you get from it. Psychologists have been trying to understand what drives our habits for over a century and one of the recurring questions is how much habits are a product of what we want versus what we
