In this study, acoustic startle probe methodology was used to examine the effects of nicotine administration and deprivation on emotional processes associated with drive and motivation (i.e., activation of the defensive system using the startle probe) with respect to genotype at the 5-HTTLPR of the serotonin transporter gene, SLC6A4. The individuals in this study were a sub-sample of a larger study addressing the effects of deprivation and nicotine administration on the acoustic startle response more generally (Cinciripini et al., 2006). Specifically, our aim was to directly test the relationship between the three 5-HTTLPR genotypes (i.e., s/s, s/l, and l/l), overnight nicotine deprivation, acute nicotine administration, and activation of the defensive system using the startle probe.
