Do picture books affect counting directionality in preliterate children? Developmental course and potential mechanisms Santiago De Torres, Julio Ramón Jiménez Carvelo, Ana María Rivera, Laura Serrano Chica, Francisca Mental number line Preliterate children Development This study was funded by grants PSI2015-67531-P to Julio Santiago, and PID2021-126589OB-I00 to Francisca Serrano, MCIN/AEI/ 10.13039/501100011033 and “ERDF (European Regional Development Fund) A way of making Europe.” Why the number line in preliterate children is already consistent with the direction of the script? Here we aimed to 1) show that being read a mirror-printed picture book is able to change lateral biases in counting; 2) trace the development of preliterate biases; and 3) test the role of mental model construction processes. Spanish-speaking 3 and 4 year-olds (N = 155, white, 87 female) carried out a task of counting a row of objects and a task in which they built a toy scene before and after being exposed to a mirror-reversed storybook. The left-to-right or right-to-left direc­ tionality of their responses was recorded. Only the older group showed pre-test lateral biases. The mirror book changed the lateral biases in counting, and induced a congruent, but smaller change in the model construction task. The two tasks did not correlate, against the implication of shared mechanisms in them. 2026-03-06T07:35:54Z 2026-03-06T07:35:54Z 2026-03-05 journal article Santiago, J.; Jiménez, A.; Rivera, L. & Serrano, F. (2026). Do picture books affect counting directionality in preliterate children? Developmental course and potential mechanisms. Journal of Experimental Child Psychology, 267, 106495. https://doi.org/10.1016/j.jecp.2026.106495 0022-0965 https://hdl.handle.net/10481/111921 10.1016/j.jecp.2026.106495 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional Elsevier