Smoking deprivation in "early" and "late" smokers and memory functions.

Reports on smoking and nicotine effects upon memory are contradictory: improvement, no change, and impairment have been observed. These inconsistencies may be due at least in part to different types of learning tasks and to experimental designs: in most studies, acute nicotine effects were analysed after previous smoking deprivation. This study compared learning, retention, and retrieval between nonsmoking after previous deprivation and "usual" smoking without previous deprivation. Twenty female smokers (S) participated in two sessions, between 8.00 and 11.00 a.m. The Austin maze and a Word Recognition Task (WRT) were applied. During the WRT, ERP were recorded from Fz and Cz scalp locations. Heart rate, CO, and subjective ratings (dizziness and smoking need) but neither WRT nor maze performance discriminated between deprivation and smoking. However, significant differences were obtained between those Ss who usually start smoking within 1 h after getting up (ES) and those who start later (LS). In maze learning and WRT, LS performed better when deprived than smoking, and ES performed better when smoking than deprived, i.e. when the time of the tests met their usual smoking habits. Results are discussed in terms of a modulation of smoking effects on memory functions by the Ss' internal state.