The cued-to respond Speed-Accuracy Tradeoff (SAT) paradigm (1) combined with external noise manipulations was used to evaluate the effects of perceptual learning on the temporal dynamics of perceptual decision. Observers were trained in a 2AFC Gabor (+/- 12°) orientation-discrimination task in eight sessions. An auditory beep occurred at one of 8 delays (SOA = 25ms to 800ms) that cued the subjects to respond. Subject's performance was constrained to 79.1% and 70.7% correct at the longest SOA by a 3-to-1 and a 2-to-1 staircase respectively that adjusted the contrast of the signal stimuli. All subjects showed learning, demonstrated by an average reduction of contrast threshold levels of 23% in high noise and 22% in low noise. An elaborated perceptual template model with a dynamic decision process (2) provided very good fits to the data. The best-fitting model included identical time constant and intercept (t0) across all the training sessions. The result suggests that perceptual learning enhances stimulus (in the zero external noise condition) and excludes external noise (in the high external noise condition) without altering the temporal dynamics of perceptual decision.