Wesnes and Parrott, 1992). For instance, Roth et al., (1992, p.253.) noted: ‘Smoking and nicotine effects on memory are contradictory. Improvement, no change, and impairment have all been observed’. There are numerous factors that need to be taken into account, with one of the most crucial being nicotine abstinence. When smokers are deprived of nicotine, they typically demonstrate mood and cognitive deficits, so that the apparently positive psychobiological effects of nicotine may often reflect the reversal of abstinence symptoms (Parrott and Garnham, 1998; Williams, 1980).
Sakurai and Kanazawa (2002) investigated the effects of smoking either no, one or two cigarettes, on Buschke’s selective reminding (memory) task, in non-deprived smokers. Performance on both the memory task and two other cognitive tests remained unchanged at the ‘normal’ level of non-smoker controls. It can also be difficult to separate memory from other cognitive functions, so that fluctuations in concentration ability may influence memory skills indirectly (Wesnes and Parrott,
1992, p.148-9). Furthermore plasma nicotine levels fluctuate in parallel with smoke inhalation patterns. This means that memory storage, consolidation and retrieval, are all occurring under constantly changing background levels of nicotine. These factors are extremely difficult to control in acute dose studies, which is why the effects of tobacco smoking on human memory functions remain unclear (Heishman et al., 1993;
Roth et al., 1992; Sherwood, 1994; Waters and Sutton, 2000). Less is known about the chronic effects of cigarette smoking on everyday cognitive function. However given the well-documented