The sensitivity of delay-related decision-making to various pharmacological manipulations of monoamine transmission are shown and compared with the effects on impulsive action in Table 2. Serotonin neurotransmission has often been implicated in delay-related decision-making. In general, lesion-induced decreases in serotonin result in an increased preference for the small-immediate- reward, while pharmacologically-induced serotonin release increases preference for the large-but-delayed reward.207–209 However, other studies have also shown serotonin antagonism to decrease delay discounting and forebrain serotonin depletion to have no effect on performance.116, 178 No studies have explored the role for -2A and -2C subtype serotonin receptors in delay-related decision making.
