Inclusion Criteria:

For part 1 of the study:

Participants fulfilling all of the following inclusion criteria are eligible for the study:

   - Consent of the patient or consent of patient's next of kin (plus consent of an
   independent physician if patient is unable to consent)

   - Aneurysmal SAH

   - Age: ≥18

   - Time of aSAH known (IMPORTANT: at least approximated. Time of aSAH refers to the bleed
   that lead to hospital admission; warning leaks in the patient history are not
   considered aSAH in this context)

   - Complete aneurysm occlusion therapy within 48h after aSAH

   - Glasgow coma scale (GCS) ≥ 13 points at time point 48h - 72h after aSAH

   - Fluent language skills in either English, German, French, or Italian

For part 2 of the study:

Participants fulfilling all of the following inclusion criteria are eligible for the study:

   - Consent of the patient or consent of patient's next of kin (plus consent of an
   independent physician if patient is unable to consent)

   - Age: ≥18

   - Acute brain injury that requires a in-patient treatment, e.g. for (surgical) treatment
   of a brain tumor, a cerebral hemorrhage, a hydrocephalus, stroke, or traumatic brain
   injury, with stable neurological and general health status

   - Glasgow coma scale (GCS) ≥ 13 points

   - Fluent language skills in either English, German, French, or Italian

Exclusion Criteria:

For part 1 of the study:

The presence of any one of the following exclusion criteria will lead to exclusion of the
participant:

   - SAH due to any other cause than aneurysm or structural abnormality of the brain
   (arterio-venous malformation, dural arterio-venous fistula, cavernous malformation,
   dissection, tumor, trauma)

   - Comatose patients or patients with a reduced vigilance of GCS < 13 at time point 48h -
   72h after aSAH

   - No aneurysm occlusion therapy within 48h after aSAH

   - Clear signs of arterial vasospasm in the initial (CT-)angiography; indicating that
   aSAH had occurred already several days prior to admission

   - Neurologic or psychiatric diseases other than aSAH that can potentially influence the
   test-performance of a patient on the MoCA (e.g., dementia, multiple sclerosis, bipolar
   disorder)

   - Foreseeable difficulties in follow-up due to geographic reasons (e.g., patients living
   abroad)

   - Patients who are not fluent in English, German, French, or Italian

   - Patients requiring sedative or other medication that would interfere with the
   neuropsychological evaluation

For part 2 of the study:

The presence of any one of the following exclusion criteria will lead to exclusion of the
participant:

   - Instable neurological or general health-status of the patient, that makes a transport
   of the patient on the ICU or the office for neuropsychological testing impossible

   - Suspected fluctuation of the neurological condition and the vigilance of the patient
   between first and second testing

   - Known psychiatric disease that can potentially influence the test-performance on the
   MoCA (e.g., dementia, bipolar disorder)

   - Patients who are not fluent in English, German, French, or Italian

   - Patients requiring sedative or other medication that would interfere with the
   neuropsychological evaluation