nl - does the participant have a significant neurologic disease such as parkinson's disease, multi-infarct dementia, huntington's disease, normal pressure hydrocephalus, brain tumor, progressive supranuclear palsy, seizure disorder, subdural hematoma, multiple sclerosis, or history of significant head trauma followed by persistent neurologic defaults or known structural brain abnormalities.<br>mci - does the participant have a significant neurologic disease other than suspected incipient alzheimer's disease such as...<br>ad - does the participant have a significant neurologic disease other than alzheimer's disease including...