[Purpose] The purpose of the current study was to compare the effectiveness of motor
sequential learning according to two different types of practice schedules, distributed
practice schedule (two 12-hour inter-trial intervals) and massed practice schedule (two
10-minute inter-trial intervals) using a serial reaction time (SRT) task. [Subjects and
Methods] Thirty healthy subjects were recruited and then randomly and evenly assigned to
either the distributed practice group or the massed practice group. All subjects performed
three consecutive sessions of the SRT task following one of the two different types of
practice schedules. Distributed practice was scheduled for two 12-hour inter-session
intervals including sleeping time, whereas massed practice was administered for two
10-minute inter-session intervals. Response time (RT) and response accuracy (RA) were
measured in at pre-test, mid-test, and post-test. [Results] For RT, univariate analysis
demonstrated significant main effects in the within-group comparison of the three tests as
well as the interaction effect of two groups × three tests, whereas the between-group
comparison showed no significant effect. The results for RA showed no significant
differences in neither the between-group comparison nor the interaction effect of two
groups × three tests, whereas the within-group comparison of the three tests showed a
significant main effect. [Conclusion] Distributed practice led to enhancement of motor
skill acquisition at the first inter-session interval as well as at the second
inter-interval the following day, compared to massed practice. Consequentially, the
results of this study suggest that a distributed practice schedule can enhance the
effectiveness of motor sequential learning in 1-day learning as well as for two days
learning formats compared to massed practice.