Therefore, it has been proposed that humans organize the regularities embedded in the environment in separate hypothesis spaces 3, 24 one such hypothesis space is based on probabilities, while another is based on deterministic rules (i.e., serial order-based regularities). Previous empirical studies suggested that the acquisition of at least two types of regularities can be differentiated: (1) statistical, probability-based regularities, and (2) serial order-based regularities 17, 21, 22, 23. Learning of regularities is not a monolithic process. The available information in our environment, which can be detected, extracted, and consolidated is diverse thus, our brain has to process several information streams simultaneously during both learning and consolidation. The present study follows this well-established behavioral test protocol to assess long-term memory performance and implements a 1-year offline period between the sessions. Consolidation can be expressed by successfully retained knowledge after the offline period (no forgetting, i.e., performance is similar in the learning and testing sessions) or by learning-dependent, delayed performance gains after the offline period, termed offline learning (i.e., performance is better in the testing session than in the learning session) 20. In the present study, we aim to investigate the long-term (1-year) consolidation of two types of regularities in neurotypical children.īehaviorally, consolidation is measured by contrasting memory performance at the end of the learning session with performance at the beginning of a subsequent testing session, without additional practice between the two sessions (i.e., during the offline periods). Although everyday experiences suggest that the representation of the acquired regularities and skills is persistent even for a more extended period (months or years), it has been rarely tested empirically, especially from a developmental perspective. Several studies investigated the consolidation of regularities and skills with a 1-min, 1-h, 4-h, 12-h, 24-h or 1-week delay 11, 12, 13, 14, 15, 16, 17, 18, 19. The initially unstable representations of the detected and extracted regularities are converted into a more stable form via consolidation, allowing information to be preserved and retained later 10. Extraction of regularities is argued to be the basis of several motor and cognitive skills, including language 3, 5, 6, 7, 8, 9. These findings offer indirect evidence for the developmental invariance model of skill consolidation.ĭetecting and extracting various kinds of regularities embedded in our environment is a fundamental component underlying human learning in all ages, enabling us to adapt to our surroundings and to predict future events 1, 2, 3, 4. Our study demonstrates that the representation of probability-based and serial order-based regularities remains stable over a long period of time. The successful retention was independent of age. Participants successfully acquired both probability-based and serial order-based regularities and retained both types of knowledge over the 1-year period.
They were then retested on the same task 1 year later without any practice between the sessions. Short-term consolidation effects were controlled by retesting their performance after a 5-h delay. Participants performed a visuomotor four-choice reaction time task designed to measure the acquisition of probability-based and serial order-based regularities simultaneously. Here, we aimed to test the long-term memory performance of probability-based and serial order-based regularities over a 1-year offline period in neurotypical children between the age of 9 and 15. However, long-term (months or year-long) memory performance of such knowledge has received relatively less attention and has not been assessed in children yet.
Memory performance of probability-based and/or serial order-based regularities over short periods (from minutes to weeks) has been widely investigated across the lifespan. At least two types of regularities contribute to acquiring skills: (1) statistical, probability-based regularities, and (2) serial order-based regularities. Extraction of environmental patterns underlies human learning throughout the lifespan and plays a crucial role not only in cognitive but also perceptual, motor, and social skills.