Nicotine Builds Brain Links Between Smoking, Environmental Cues

It's no accident that smokers associate certain situations, behaviors and activities with smoking: researchers say that nicotine actually helps cement links between environmental cues and smoking in the brain, HealthDay News reported Sept. 9.

“Our brains normally make these associations between things that support our existence and environmental cues so that we conduct behaviors leading to successful lives. The brain sends a reward signal when we act in a way that contributes to our well being,” said study co-author John A. Dani of the Baylor College of Medicine. “However, nicotine commandeers this subconscious learning process in the brain so we begin to behave as though smoking is a positive action.”

Researchers exposed mice to nicotine and compared their brain activity when they were in an area where they received the drug and an area where they received a saline solution. “The brain activity change was just amazing,” Dani said. “Compared to injections of saline, nicotine strengthened neuronal connections — sometimes up to 200 percent. This strengthening of connections underlies new memory formation.”

The study appears in the Sept. 10, 2009 issue of the journal Neuron.