Why cigarettes taste so bad — at firstPreviously, it was thought that the disgust associated with that first cigarette was driven by nicotine, which can stimulate both pleasure and aversion neurons in the brain. But the new results suggest that when a person smokes for the first time, both reward and aversion brain cells are activated. These sensations link back to two populations of brain cells found in the ventral tegmental area (VTA) of the brain, part of the reward system.Taryn Greider, a scientist at the University of Toronto and author on the study, tells Inverse that the main things that lead to smoking feeling good or bad are an increase in the number of receptors in our brains and a change in how the different structures in the brain communicate with each other.