The best-studied temporal tasks in humans are interval and duration discrimination (Divenyi & Danner 1977, Getty 1975, Wright et al. 1997). In a typical interval discrimination task two brief tones separated by a standard interval (T, e.g., 100 ms) or longer interval (T + T) are presented to the subject. The presentation order of the short and long intervals is randomized. The subject may be asked to make a judgment as to whether the longer interval was the first or second.T can be varied adaptively to estimate the interval discrimination threshold. Duration discrimination tasks are similar, except each stimulus is a continuous tone (filled interval).