An alternative explanation for the age-related difference in locational preference observed in this study is that conditioning of one-trial ethanol-mediated SOC may simply have been more effective in adults than in adolescents The absence of conditioned motor responses in paired adult subjects might be taken as evidence of a lack of first-order conditioning at this particular age. Furthermore, degree of training was not explicitly varied in these studies. Yet, previous literature indicates that adult rats acquire and express second-order conditioning (e.g., Rescorla, 1980) and are also capable of detecting differences in the present tactile stimuli (i.e., sandpaper and smooth surfaces; Hughes, 2007). Adult rodents are also likely to exhibit better learning performance than adolescents in tasks in which hyperactivity is likely to detract from performance of the conditioning (Spear & Brake, 1983). The conditioned place preference task employed in the present work is probably one of those tasks. Adult subjects also showed an association between behavioral activation during the transfer phase and sandpaper scores. These facts suggest that adults are capable of encoding and acquiring information about the state of
