Using Cognitive Capacity in Reading Text

Abstract

Use of cognitive capacity in reading was measured with a secondary task. In this technique, reaction times to clicks which occur rarely and unpredictably during a primary task are used to measure the capacity demands of the primary task. As the primary task uses more capacity, less spare capacity is available and secondary task performance declines—reaction time to the clicks slows down. Results for 24 undergraduates showed that reaction times to clicks were slower while subjects were reading than in an otherwise equivalent condition in which they were not reading. This indicates that the reading task uses capacity even though it is very highly practiced.