Yet the most popular and widely viewed instructional videos available onlinelargely fail to leverage the power of gesture, according to a team ofpsychologists from UCLA and California State University, Los Angeles. Theresearchers examined the top one hundred videos on YouTube devoted toexplaining the concept of standard deviation, an important topic in the study ofstatistics. In 68 percent of these recordings, they report, the instructor’s handswere not even visible. In the remaining videos, instructors mostly used theirhands to point or to make emphatic “beat” gestures. They employed symbolicgestures—the type of gesture that is especially helpful in conveying abstractconcepts—in fewer than 10 percent of the videos reviewed.
Symbolic gestures, which are the most valuable for relaying abstract information, are some of the least seen in online digital pedagogy. Slightly more frequent are "beat" gestures that are used for emphatic emphasis, while in the majority of studied online instructional videos the lecturers hands aren't seen on the video at all.