It turns out that dopamine is a chemical on double duty in the brain. Along with its role in motor commands, it also serves as the main messenger in the reward systems, guiding a person toward food, drink, mates, and all things useful for survival. Because of its role in the reward system, imbalances in dopamine can trigger gambling, overeating, and drug addiction - behaviors that result from a reward system gone awry.
David EaglemanI spent my adult life as a scientist, and science is, essentially, the most successful approach we have to try and understand the vast mysteries around.
David EaglemanEven though the outside world has not changed, your brain dynamically presents different interpretations.
David EaglemanThe deep secret of the brain is that not only the spinal cord but the entire central nervous system works this way: internally generated activity is modulated by sensory input. In this view, the difference between being awake and being asleep is merely that the data coming in from the eyes anchors the perception.
David Eagleman