As described above, each session consisted of a habituation and test block of trials. Participants received an administration of nasal spray prior to each block. Prior to the habituation block all participants received placebo spray. This provided an opportunity for adaptation to any aversive effects of the nasal spray (in addition to habituation to the probes). Prior to the test block, smokers received either nicotine (1 mg) or placebo (0mg) nasal spray counterbalanced within deprivation condition. In all cases the spray was administered following an initial 5-min rest period. Participants self-administered one spray (metered dose) per nostril (either 0 or 0.5 mg nicotine per spray). Participants were blind to the content of the spray. This was followed by a 5-minute absorption period, after which the trial block and physiological recording began. Peak arterial levels of nicotine of about 10 ng/ml have been reported to occur within five minutes of a single application of the nicotine nasal spray (0.5 mg/nostril) (Gourlay & Benowitz, 1997). The nicotine and placebo spray were provided by Pharmacia & Upjohn Inc, and the nicotine spray is marketed as a nicotine replacement product (Nicotrol NS).
