As in our previous studies (Cooper et al. 2014 (link); Wallin and Wood 2015 (link)), rats received daily injections sc of 7.5 mg/kg testosterone (Steraloids, RI) or vehicle (3% ethanol and 13% cyclodextrin (RBI, MA) 5 d/wk, beginning at 5 weeks of age. Pubertal treatment mirrors patterns of human use, where 4–6% of high school boys in the United States have used AAS (Johnston et al., 2013 ). Furthermore, AAS have the strongest behavioral effects in rodents when introduced in adolescence (Salas-Ramirez et al., 2008 (link)). Injections were delivered immediately before rats were placed in the operant chambers. Rats received injections for at least two weeks prior to behavioral testing, and daily injections continued for the duration of the experiment (Figure 1B). testosterone was used because it is the endogenous AAS, and accounts for the largest number of adverse analytical findings (55.5%) in urine tests by World Anti-Doping Agency-accredited laboratories (WADA 2012 ). At 7.5 mg/kg, this dose approximates a heavy steroid dose in humans, and has been used to test effects on rodent discounting behavior (Cooper et al. 2014 (link); Wallin and Wood 2015 (link); Wallin et al, 2015 (link); Wood et al, 2013 (link)).