Arousal in its most general sense refers to readiness of a person to perform work. To achieve an optimum level of task performance, it is necessary to have a certain level of stimulation or arousal. This level of stimulation or arousal varies from person to person. There are people who are overloaded by having to do more than one task at a time; on the other hand, there are people who thrive on stress, happy to take on more and more work or challenges. Figure 16 shows the general relationship between arousal and task performance.