Subjects who are decisionally impaired are considered a potentially vulnerable population. irbs must ensure that:

The IRB must ensure, when designing a study, that those who are impaired are not subject to coercion or undue influence upon their responses. In addition, they are to be ensured that they are being equitably selected by the researchers, and that their capacity to consent is measured properly and that the consent itself truly is voluntary.

It’s because it’s was very fun