The mean observer similarity for each age bin, as indicated by the average pairwise correlation of observer-specific dwell time distributions across objects. A total of 6,720 participants were included in the analysis; for a more detailed distribution of participants across age groups, please refer to Fig. 2 . Note that for a , c and d , each age bin spans two years. Due to space constraints, only every second tick mark is labelled. The red shading marks age bins with lower sensitivity to developmental changes, which were disregarded for curve fitting ( n < 90 per bin). All error bars indicate 1 s.e.m., and the lines indicate the best-fitting polynomial. The lines above each plot indicate the level of evidence for a given bin to be part of a broad linear change via shades of grey, as shown in the key (sliding window analysis; see main text and Methods ). Panel b adapted from ref. 36 under a Creative Commons license CC BY 4.0 .
