Influence Of Playback Speed On Learning Effects And Intervention From The Perspective Of Cognitive Load

Playback speed is a technology based on changing the amount of video picture information without distorting the quality of interpretation or lecturer output.There are different theoretical explanations for the role of playback speed on learning: accelerated playback hypothesis,stimulus-driven attention capture theory,and fluency theory support that accelerated play speed can promote learning,while multimedia learning theory and cognitive load theory believe that fast playback will hinder learning.In previous empirical studies,it is found that fast playback has an approximately moderate hindering effect on learning effect,which is mainly reflected in the retention test(d=-0.46)and the transfer test((d=-0.38).However,there is no consensus on the effect of playback speed on learning.If fast play interferes with the learning effect by increasing the cognitive load of learners,can it help learners actively adapt to rapid play by developing their internal resources and using external learning means based on cognitive load? Accordingly,this study explored these questions through three experiments from the eye-movement level.In experiment one,a two-factor between-subject experiment design was used to investigate the influence of playback speed on cognitive load and learning effect from the eye movement level.The experiment revealed that the mental effort of the subjects in the normal speed play group was significantly lower than that of the fast play group.Accordingly,the scores of the retention tests and transfer tests of the normal speed group were significantly higher than that of the fast play group,and the cognitive load was significantly negatively correlated with the learning effect,indicating that the fast play would increase the cognitive load level in the learning process and then interfere with the learning effect.Experiments two and three combined with eye tracking technology,based on cognitive load,tried to explore whether high working memory capacity and cognitive unloading can reduce the cognitive load under fast playback conditions and help them to adapt to fast playback from the perspective of learners’ internal resources and external learning means.Experiment 2 found that under the condition of fast playing,high working memory capacity learners had lower cognitive load,and their scores of retention tests and transfer tests were significantly lower than those of learners with low working memory capacity.Experiment 3 found that in the teaching video of the cognitive unloading part,the subjects of cognitive unloading group had higher cognitive load than that of the control group,and their scores of the retention tests and transfer tests were lower than that of the control group,but the difference was significant at edge,and the difference between the two groups were not significant in the subsequent non-cognitive unloading video part.This study drew the following conclusions:(1)faster playback speed interferes with learning effects by intervening with cognitive load.(2)High working memory capacity can effectively adjust the cognitive load,improve the learning effect of learners,and alleviate the damage of the learning effect caused by the accelerated playback speed.(3)Cognitive unloading will increase the cognitive load in the strategy implementation stage and disturb the learning effect,but there is no obvious interference effect for effect on subsequent learning.