How is the concept “disorders of brain function” related to Fred’s presenting symptoms?

Chapter 20

Fifty-four–year-old Fred is complaining of a headache that started about 2 weeks ago. For the past 2 days, the headache has increased in severity, and he is photophobic and has uncial rigidity and projectile vomiting. CT scan results show an arteriovenous malformation in the basal artery and a small hemorrhagic bleed in the middle meningeal artery.