Interferência retroativa e esforço cognitivo via dilatação pupilar na consolidação da memória na aprendizagem motora

Abstract

Memory consolidation is crucial for the retention of motor learning. However, it is susceptible to interference. Retroactive Interference (RI), which occurs when more recent memories interfere with the retrieval of older ones, negatively affects the consolidation of motor learning. Nevertheless, it can also strengthen consolidation if the target and interfering information are acquired and recalled together. Another factor involved in consolidation is the level of cognitive effort employed, which is higher in the early stages and lower in the later stages of motor learning. Thus, measuring cognitive effort throughout learning can provide a more accurate understanding of the mental load involved in each phase, contributing to the interpretation of the mechanisms of motor memory consolidation and retention. The aim of the study was to investigate the effect of retroactive interference on the consolidation of a motor skill and its relationship with cognitive effort. The sample consisted of 66 university students, average age of 22.5 years, of both sexes, right-handed, and inexperienced in the tasks. Two tasks were performed: one motor task, serial reaction time (target learning), and one cognitive task, the Rey Auditory Verbal Learning Test (interfering task). Participants were randomized into 3 groups: positive RI effect (GRI+), negative RI effect (GRI-), and no RI effect (GSI). The study was developed in an acquisition phase and a retention test, with a 24-hour interval between them. In the acquisition phase, all 3 groups performed the motor task (72 trials). Afterwards, GRI+ and GRI- performed the cognitive task. In the retention test, GRI+ again performed the cognitive task, followed by the motor task, while GRI- and GSI only performed the motor task. Throughout the practice, an eye tracker was used to monitor pupillary dilation. The variables analyzed were reaction time (RT), movement time (MT), total time (TT) and offline learning. The GRI+ group showed significantly better performance than the GRI- and GSI groups in the retention test for all variables. Pupil dilation was also significantly lower in the GRI+ group, reflecting less cognitive effort employed. It is discussed that performing the cognitive task again in the retention test created a contextual situation similar to that practiced, which contributed to the retrieval of motor memory. These findings highlight the relationship between contextual factors and the stabilization of an acquired motor skill, indicating that contextual characteristics play a fundamental role in both the consolidation and retrieval of motor memory, as well as in the different levels of cognitive effort required during the learning process.