The world is full of options. So how do we know which goal to pursue and how much effort to put in? And how can we keep track of our progress towards these goals? All these questions point to the action of one neurotransmitter in the brain: dopamine. Yes, dopamine has been previously linked to pleasure or “reward”. Dopamine is still widely believed to do all sorts of things such as getting people hooked on drugs or even cell phones. However, by now, it is well-established that altering dopamine in the brain does not change one’s pleasure in receiving rewards. Instead, dopamine comes into play whenever motivated behavior must be adjusted to pursue a goal.
Continue reading “Breaking the shackles of reward: dopamine’s role in exploration”
Many things in life are simple to describe, yet difficult to understand. One such obvious fact is that if one consumes more calories than one expends, this will eventually lead to weight gain and, ultimately, overweight and obesity. But what causes the excess in consumption that has propelled the surge in obesity in the past decades?
Intuitively, it is tempting to assume that overeating is driven by greater pleasure derived from eating. To examine the cause for overindulgence, we often present food cues and track how the brain evaluates them. Such cues range from pictures of palatable food to simple geometric shapes predicting the delivery of chocolate milkshake in the scanner. In line with the “reward surfeit” idea, many studies have observed an increased response to food cues in the brain’s reward circuit in overweight and obese individuals. This is then interpreted as an increased desire elicited by the prospect of food. Continue reading “Too much or too little reward from eating: why do we overeat?”