Attention span

Attention span is the amount of concentrated time one can spend on a task without becoming distracted. Most educators and psychologists agree that the ability to focus and sustain attention on a task is crucial for the achievement of one's goals.

Estimates for the length of human attention span are highly variable and depend on the precise definition of attention being used.

Attention span, as measured by sustained attention, or the time spent continuously on task, varies with age. Older children are capable of longer periods of attention than younger children.

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. Attention is also increased if the person is able to perform the task fluently, compared to a person who has difficulty performing the task, or to the same person when he or she is just learning the task. Fatigue, hunger, noise, and emotional stress reduce the time focused on the task. Common estimates for sustained attention to a freely chosen task range from about five minutes for a two-year-old child, to a maximum of around 20 minutes in older children and adults.

After losing attention from a topic, a person may restore it by taking a rest, doing a different kind of activity, changing mental focus, or deliberately choosing to re-focus on the first topic.

Many different tests for attention span have been used in different populations and in different times. Some tests measure short-term, focused attention abilities (which is typically normal in people with ADHD), and others provide information about how easily distracted the test-taker is (typically a significant problem in people with ADHD). Tests like the DeGangi's Test of Attention in Infants (TAI) and Wechsler Intelligence Scale for Children-IV (WISC-IV) are commonly used to test for attention-related issues in young children when interviews and observations are inadequate. Older tests, like the Continuous Performance Test and the Porteus Maze Test, have been rejected by some experts. These tests are typically criticized as not actually measuring attention, or as being inappropriate for some populations, or as not providing clinically useful information.

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