The effect of video playback speed on learning and mind-wandering in younger and older adults

Prior work has demonstrated that watching videos at faster speeds does not significantly impair learning in younger adults; however, it was previously unclear how increased video speed impacts memory in older adults. Additionally, we investigated the effects of increased video speed on mind-wandering. We presented younger and older adults with a pre-recorded video lecture and manipulated the video to play at different speeds. After watching the video, participants predicted their performance on a memory test covering the material from the video and then completed said memory test. We demonstrated that although younger adults can watch lecture videos at faster speeds without significant deficits in memory, older adults' test performance is generally impaired when watching at faster speeds. Additionally, faster playback speeds seem to reduce mind-wandering (and mind-wandering was generally reduced in older adults relative to younger adults), potentially contributing to younger adults' preserved memory at faster speeds. Thus, while younger adults can watch videos at faster speeds without significant consequences, we advise against older adults watching at faster speeds.