Ironically, some of the best behavioral data on these matters now come from functional brain imaging studies of reward processing (e.g., Adelman et al., 2002; Bjork et al., 2004; Ernst et al., 2005; Fareri et al., 2008; Galvan et al., 2006; May et al., 2004; Van Leijenhorst et al., 2009) and self-regulation (e.g., Durston et al., 2002; Luna et al., 2001; Rubia, et al., 2006; Stevens et al., 2007; Tamm et al., 2002; Velanova et al., 2008). It is true that there are limits on how closely one can mimic real world situations in laboratory paradigms, but these seem no more troublesome to me than the constraints on any experimental research. Indeed, one reason these studies are so important is that in the lab it is possible to construct tasks that have equivalent meaning to people of different ages and, if necessary, to manipulate performance so that brain functioning can be compared both with and without equivalent performance (see Blakemore et al., this issue; Luna et al., this issue).
