Behavioral discrimination and categorization task results. a, The same–different task can give an indication of categorical perception, while (c) the explicit categorization task is necessary to indicate the location of the category boundary: CD, 6.32 with a 95% CI of [6.24–6.41], and PT, 5.52 with a 95% CI of [5.46–5.59]. b,d, RTs are in line with the effect found for both tasks (i.e., show the reversed pattern). *Error bars correspond to standard errors of the mean.