Abstract
Visual perceptual learning (VPL) is an enduring improvement in performance following training on a visual task. VPL of texture discrimination is retinotopically specific, and consolidation of this learning is enhanced by rapid eye movement (REM) sleep (Mednick et al., 2003). Interestingly, endogenous acetylcholine (ACh) release is elevated during REM sleep. Cholinergic enhancement increases the magnitude and specificity of VPL for motion direction discrimination, and this benefit is maintained for at least several months after the end of training and drug administration (Rokem & Silver, 2010; 2013). Here, we conducted a double-blind crossover study to determine if cholinergic enhancement would facilitate texture discrimination learning and, if so, at what time scale. Each subject participated in two training sessions in which they were administered either 5 mg of donepezil, which prolongs the signaling of endogenous ACh, or placebo. These training sessions (experimental days 1 & 15) were spaced two weeks apart to allow for complete elimination of the drug (if present). Learning was assessed one day after each training session (short-term: days 2 & 16) and again either 2 or 4 weeks later (long-term: day 29). We also examined specificity of VPL by measuring performance in an untrained visual field location on day 29. Significant VPL was evident in both short- and long-term testing sessions. However, we found no significant effect of training with donepezil compared to placebo for either short- or long-term VPL. Unexpectedly, we found that regardless of drug condition, significantly more VPL was observed in visual field locations that were trained 4 weeks prior compared to those trained 2 weeks prior. This suggests that consolidation of VPL can continue for as long as a few weeks after the end of training.
Meeting abstract presented at VSS 2017