Getting the person to pay attention is not as simple as yes or no because sustained attention is not the same for every activity, every person or even the same person at different times of the day. While there is some predictability about how much attention can be aroused with each ACL, that too has variations. The goal is to get the best and most attention as possible.
Sustained attention is the investment and consumption of energy while doing an action, activity or occupation. The amount can vary and the variations can be explained by reductions or increases in neurophysiological functions or personal choices.
Personal choice is noticeable after attention has been aroused and during the process of sustained attention. You may notice that the amount of energy invested follows a pattern. A common pattern is a decrease in the amount of energy invested within the sustained attention time period, which can be recorded and compared for time of day or changes in the person's medical condition.