Here is the breakdown:They believed the cigarette contained nicotine but received a placebo. They believed the cigarette did not contain nicotine but received a nicotine cigarette. They believed the cigarette contained nicotine and received nicotine. The scans showed significant neural activity that correlated to both craving and learning signals when participants smoked a nicotine cigarette and believed its nicotine content was genuine. Reduced cravingsThe smokers who got the nicotine, or simply believed they did, reported reduced cravings and the scan recorded increased neural activity.

Source: CBC News September 13, 2016 19:18 UTC