[5] For time-on-task measurements, the type of activity used in the test affects the results, as people are generally capable of a longer attention span when they are doing something that they find enjoyable or intrinsically motivating.A research study that consisted of 10,430 males and females ages 10 to 70 observed sustained attention time across a lifespan.The data collected from the study concluded that attention span is not one singular linear equation; at age 15 it is recorded that attention-span-related abilities diverge.Over the course of the study, collected evidence additionally found that, in humans, attention span is at its highest level when a person is in their early 40s, then gradually declines in old age.The study also found that student awareness and productivity increased after a two-day weekend but substantially decreased after summer break.