Abstract
Sex differences in cognitive performance have been found for explicit memory tasks (Lewin et al. 2001), but few studies have reported sex differences on perceptual tasks. We investigated differences between young men and women in perceptual learning (PL) of a motion direction discrimination task (Rokem and Silver 2010) using a nap paradigm (Mednick et al. 2003). At 9AM, thresholds were obtained for two directions of motion, followed by 40min of training on one of those two directions of motion. Subjects were classified into one of two groups: nap (60-90 min; with polysomnography) and no-nap. At 4PM, thresholds were reassessed for the trained and untrained directions of motion as well as a direction of motion that was not previously tested. Men who napped (n=28) showed increased learning of the trained direction of motion relative to men who did not nap (n=25) and no learning of the untrained or novel motion directions in either the nap or no-nap conditions. In contrast, women in both the nap (n=42) and no-nap (n=28) conditions showed significant learning of both the trained and untrained motion directions. Women also showed learning for the novel motion direction following a nap, compared to no-nap. In conclusion, extending previous studies (Mednick et al. 2003, 2005), we found that short naps play an important role in the consolidation of PL in motion perception but that this effect is specific to men. Men required sleep to show learning of a trained motion direction, whereas women performed equally well after either wake or sleep. Additionally, men who napped showed high direction specificity for learning of the trained motion direction, whereas women who napped exhibited generalized learning to the untrained and novel motion directions.
Meeting abstract presented at VSS 2012