Here is an excellent article from the University of Michigan, a nice and quick 6 page study that goes over many elements of nicotine and how it affects the central nervous system. We have posted many studies on how nicotine improves cognition, but it is also vital to know how it affects the other parts of our systems. Here are a few interesting points in the article above: ""Dose-dependent neurotransmitter and neuroendocrine effects occur as plasma nicotine levels rise when a cigarette is smoked. Circulating levels of norepinephrine and epinephrine increase, and the bioavailability of dopamine is altered as well. "" ""In rats, subcutaneous administration of nicotine has been shown to produce dose-dependent increases in cerebral glucose uptake, indicating heightened brain metabolic activity."" ""The impact of nicotine on the central nervous system is neuroregulatory in nature, with cascading effects on physiological and biochemical functions."" ""(Figure 1 shows the effects of smoking a typical cigarette [approximately 1 mg nicotine content].) Even when there is only a modest increase in plasma nicotine level (as seen in individuals who have already smoked several cigarettes during the day), a profound increase in circulating norepinephrine levels is observed."" ""Several of the neuroregulators that exhibit altered bioavailability in response to nicotine are known to have behavioral manifestations . Control of sympathetic tone via norepinephrine mediation in the locus coeruleus, for example, may facilitate ability to focus and concentrate. Central acetylcholine release has been shown to be involved in memory and task performance, thereby implicating the cholinergic component of the nervous system. In addition to its antidiuretic and vasoconstrictive effects, arginine vasopressin has been associated with memory consolidation and retrieval."