Dados do Trabalho

Título

Sleep’s beneficial effect on problem solving is not additionally increased by Targeted Memory Reactivation.

Introdução

The active systems consolidation hypothesis proposes that memories undergo reactivations during sleep that can give rise to qualitative changes of the representations. These changes may allow for the generation of new knowledge such as gaining insights into solutions for problem-solving. Targeted Memory Reactivation (TMR) has been successfully applied to improve memory consolidation during sleep, however, little is known about the effect of TMR on problem-solving

Objetivo

To test whether TMR during slow-wave sleep (SWS) and/or rapid eye movement (REM) sleep increases problem-solving beyond the beneficial sleep effect.

Métodos

Young healthy volunteers participated in one of two experiments. Experiment 1 tested the effect of sleep on problem-solving. Subjects were trained in a videogame-based problem-solving task until being presented with a non-solved challenge. Followed by an incubation interval filled with sleep (n=21) or wakefulness (n=21), subjects were tested on the problem-solving challenge again. Experiment 2 tested the effect of TMR on problem-solving, with subjects receiving auditory TMR either during SWS (SWSstim, n=18), REM sleep (REMstim, n=19) or wakefulness (Wakestim, n=21), using the same protocol as in experiment 1. Control tasks were applied to test for mood, sleepiness, working memory and psychomotor vigilance.

Resultados

In Experiment 1, sleep improved problem-solving, with 61.9% of subjects from the Sleep group being able to solve the problem after the incubation interval in comparison to 23.8% from the Wake group (p=0.013, with a medium effect size of Phi=0.39). Subjects who solved the problem in the Sleep group presented more SWS in comparison to the ones who did not solve the problem (p=0.01). No significant difference was found for control variables. In Experiment 2, TMR did not change the sleep effect on problem-solving: 55.6% of subjects from the SWSstim group and 57.9% from the REMstim group solved the problem, while 57.1% from the Wakestim group did so (p=0.86). No associations with sleep stages were found and there were no significant differences in control variables.

Conclusões

Sleep facilitates problem-solving. However, auditory TMR during sleep does not provide additional benefits, neither TMR during SWS nor during REM sleep. Future studies may test varying protocols of TMR, which may produce different results

Palavras-chave

Problem-solving; Active system consolidation; memory, insight; sleep,