how long is a person attention span
1 Some state that the average human attention span is approximately 5 minutes; others state that most healthy teenagers and adults are unable to sustain attention on one thing for more than about 20 minutes at a time, although they can choose repeatedly to re-focus on the same thing. Transient attention is a short-term response to a stimulus that temporarily attracts/distracts attention. 2  Researchers disagree on the exact amount of human transient attention span; some say it may be as short as 8 seconds.