Dementia syndromes: neurobehavioral and neuropsychiatric features.

Dementia is seen in a wide variety of conditions that, in general, lack specific laboratory features. Etiologic classification depends on a combination of historical/clinical and radiologic/EEG considerations. Neurobehavioral and neuropsychiatric characteristics of the dementia syndromes may be key to accurate diagnosis. The diseases that produce dementia syndromes, including degenerative, vascular, myelinoclastic, traumatic, infective, and metabolic disorders, are reviewed, and the principles that permit differential diagnosis are discussed.