Faster than an injection, more reinforcing than crack cocaine: Smoking a cigarette speeds nicotine to the brain faster than any other delivery method, giving smokers precise control over their exact nicotine dose with each puff they take. It turns out that those two attributes--speed and control--greatly enhance nicotine's addictive effect on the brain. "It's not just the drug, but how you take it," says Timothy Baker, associate director, University of Wisconsin Center for Tobacco Research and Intervention. "Cigarette smoking introduces nicotine to the pulmonary beds of the lungs, which means it gets to the brain in seconds, without achieving general venous circulation."
Nicotine mimics the neurotransmitter acetylcholine, binding to and activating a subset of receptors (the nicotinic acetylcholine receptors). Nicotine affects the brain in much the same way as cocaine, opiates, and amphetamines do; it is hard to say which drugs are more addictive. Animals can be trained to self-administer ...
