Concurrent diagnosis of organic brain syndrome, dementia, mental retardation, or significant sensory deficit Concurrent diagnosis of organic brain syndrome, dementia, mental retardation, or significant sensory deficit Concurrent diagnosis of organic brain syndrome, dementia, mental retardation, or significant sensory deficit Diagnosis of mental retardation. Concurrent diagnosis of organic brain syndrome, dementia, mental retardation, or significant sensory deficit Those with concurrent diagnosis of organic brain syndrome, dementia, mental retardation, non-English speaking, or significant sensory deficit History of mental retardation unrelated to brain tumor