I've had computer based neuro-psych testing done as part of my most recent Neuro-Psych Assessment. Don't worry about it. It may cause you to get fatigued but that is an integral part of the test. It measure various responses by presenting questions or sequences for you to respond to.

If you start to get fatigued, just do as good as you can. If your scores start to drop, the result will show this. It will be a good indicator of your brain's current function level.

It is not uncommon for you to need a few days to recover from the effort and stress loads. As I said, stressing your brain is integral to the test.

Plan a normal day with no unusual preparations. Relax and just do the tests. There will likely be multiple tests with short breaks between them for the technician to set up the next test sequence.

Relax and just do what you can.

My best to you.