Pick’s disease is a rare, progressive and irreversible form of dementia. Dementia means that the brain does not function normally and patients can have difficulty with language, behavior, cognition (thinking), judgment, and memory.Memory changes are seen in other forms of dementia like Alzheimer’s disease.ementia means that the brain does not function normally and patients can have difficulty with language, behavior, cognition (thinking), judgment, and memory. Memory changes are seen in other forms of dementia like Alzheimer’s disease.