Final answer:
Controlled processes require selective attention because they are complex tasks that need focused mental effort. For instance, searching for misplaced keys with a specific color and size illustrates this selective focus. The 'selective attention test' also shows how concentrating on one aspect can lead to missing other details.
Step-by-step explanation:
Controlled processes require selective attention due to their complex, effortful, and deliberate nature. An example of this is the act of looking for misplaced keys. If you had a yellow key fob, you would selectively search for an object of a certain size and color in probable locations. This illustrates how selective attention allows us to focus on specific details that are relevant to the task at hand, ignoring others. The Simons and Chabris "selective attention test" demonstrates how our focus on one task can make us overlook other stimuli, encompassing the concept of inattentional blindness. Such focused attention demands significant mental energy and can lead to increased blood flow to the brain, reflecting the intensive nature of controlled processes.