Uncovering the latent structure of human time perception

One of the ongoing controversies in interval timing concerns whether human time perception relies on multiple distinct mechanisms. This debate centres around whether subsecond and suprasecond timing may be attributed to a single semi-uniform timing system or separate and interacting cognitive systems. Whereas past studies offer valuable insights, this study overcomes previous limitations by adopting multiple convergent statistical approaches in a design with strong statistical power. We conducted two online experiments involving participants reproducing temporal intervals ranging from 400 to 2400 ms (Experiment 1; N = 302) and 1000 to 2000 ms (Experiment 2; N = 302). We contrasted the application of exploratory factor analysis and structural equation modelling to differentiate distinct latent structures underlying duration reproduction patterns. Additionally, we compared the model outcomes with results from changepoint analysis models fitted to individual participants' data. In both experiments, these analyses yielded evidence for a two-factor model comprising a general timing factor spanning the full interval range and a second factor capturing the regression to the mean of presented stimulus intervals (central tendency bias). We observed a low proportion of detected changepoints, further supporting the limited evidence for a hypothesized discontinuity between distinct underlying systems, while also finding that changepoint detection patterns were predicted by latent factor scores. These results suggest that the central tendency bias should be considered when investigating potential discontinuities in interval timing systems. Our work contributes to the integration of factor analytic and computational modelling approaches in the study of time perception and has implications for the measurement and interpretation of interval timing in a range of contexts.