In a world where time is the most valuable resource, more and more people are getting used to listening to podcasts, audiobooks, or educational videos at an accelerated speed. This practice is especially actively used by young people. But does rapid consumption of content really help to better absorb information, or, on the contrary, harm memory and concentration? Scientists from Canada and the USA tried to answer this question.
What are the advantages?
Fast playback is convenient. It allows you to get more done in the same amount of time or review the material again. For students, this can mean extra hours of practice or preparation. What’s more, listening at 1.5x speed can even help you focus better — there’s no time for distraction.
But there is a flip side
The human brain works with new information in several stages: first it "encodes" it, then stores it, and later reproduces it. And it is at the first stage - when we try to understand the meaning of what we hear - that difficulties arise at high speed. After all, the load on working memory increases sharply.
Our brains can technically process up to 450 words per minute (twice the normal speed of speech). But if information comes in too fast, some of it doesn't have time to be fully processed—and simply "disappears.".
What the research says
A recent meta-analysis included 24 experiments comparing the perception of educational videos at different speeds. The results are as follows:
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At 1.25x or 1.5x speed, the level of absorption almost does not change.
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At 2x speed, it decreases noticeably.
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At 2.5x, up to 17% of information is lost.
That is, a slight acceleration is quite acceptable, but on condition that the listener does not lose pleasure from the process.
Age matters
A particularly interesting observation: older people perform worse on fast-paced content. In the 61–94 age group, the deterioration in performance at accelerated speeds was noticeably stronger than in the 18–36 age group. This is likely due to a decline in cognitive functions, particularly working memory.
What about the long-term impact?
Scientists still can't say for sure whether high-speed training can reduce the negative effects. There is speculation that getting used to a fast pace can even train cognitive endurance. But whether this leads to increased mental fatigue is an open question.
And, ultimately, pleasure
Research also shows that even if memory doesn't suffer at 1.5x speed, people may simply not like it. Reduced enjoyment of the process reduces motivation, which directly affects the quality of learning.
So while scientists continue to study, the best advice is to listen to yourself. If the pace doesn't hurt your learning or your comfort level, go for it. But if the speed turns studying into stress, it might be time to slow down.
