Presentation description

Memory consolidation, the process by which newly learned information is transformed into robust memories, was historically thought to be a slow process that developed over time periods spanning hours to days following completion of learning sessions. However, more recent research has shown that consolidation may occur faster, i.e., during the seconds of rest interleaved with bouts of practice during initial learning. Previous research aiming at optimizing consolidation has never considered these early windows of plasticity. The goal of this study was to use Target Memory Reactivation (TMR), an intervention known to boost the slow consolidation process, to modulate fast consolidation occurring during the rest periods interspersed within task practice. In TMR protocols, sensory stimuli (e.g. sounds) that are associated with the learned material during the learning episode are presented offline, during the consolidation interval, to reactivate the encoded memory trace. Thirty young healthy adults performed a training session on a bimanual audio-motor finger tapping task in which auditory tones were associated with each key press to create an association between a sequence of finger taps and a unique melody. Participants were distributed in 3 groups according to the TMR condition, i.e., according to the stimulation administered during the inter-practice rest periods. In the congruent group, auditory stimuli that matched the melody of their assigned sequence was administered during rest. In the incongruent control group, the auditory stimulation consisted in random tones. In the no stimulation control group, no auditory stimuli was administered. All groups were retested on the task 24hrs after training. Preliminary findings suggest a trend towards increased fast consolidation in the congruent group compared to the two control groups while also revealing decreased gains at the 24hr retest. This suggests there may be consolidation processes happening during these early plasticity windows which have a competitive relationship with traditional slower consolidation.