Symptoms, which develop primarily in young adults, include hemorrhaging, headaches and seizures, as well as neurological problems such as memory loss, paralysis, and loss of motor skills or speech capability. These symptoms can occur even if the arteriovenous malformations do not rupture or bleed.People who have a subarachnoid hemorrhage (a type of stroke) can develop more serious problems and may need immediate treatment. As many as 45% of people with a subarachnoid hemorrhage will experience severe headaches as an early symptom. About 50% may faint or become unconscious. Other early symptoms include stiff neck, vomiting, nausea, seizures, or mental status changes.
