Shift from offline to online learning definitively reveals age-related changes in sequential learning.

One of the methods most commonly used to assess implicit learning is the Serial Reaction Time Task (SRTT), which involves learning a visuo-motor sequence. However, the developmental trajectory of sequence learning and its underlying processes continues to be a matter of debate. Du et al. (2017) showed that adults primarily rely on online learning mechanisms, whereas the learning gains of 6-year-old children mainly occur during offline periods (i.e., rest intervals). Interestingly, 10-year-olds showed a mixed pattern, combining both online and offline learning processes. These findings suggest differential learning strategies (Du et al., 2016). However, Du et al.’s (2017) results were obtained using an atypical version of the SRTT (i.e., foot responses). This raises the question of whether the observed developmental changes reflect genuine age-related shifts in learning strategies or, instead, age-specific sensitivities to task design. To address this issue, we conducted a partial replication of Du et al. (2017) using a touch-screen SRTT specifically adapted to minimize age-related biases (Experiment 1). We also investigated the effect of explicit instruction on these developmental learning patterns (Experiment 2). Findings confirm age-related differences in learning dynamics. Moreover, results show that online learning was directly related to explicit knowledge assessed with verbal reports, as well as with generation and recognition tasks. Finally, providing explicit instructions disrupted established learning patterns, interfering, in particular, with sequence acquisition in 10-year-olds. These findings are discussed in terms of how individual (i.e., age) and contextual (i.e., task instructions) factors may influence the balance between online and offline learning.