Memory function and the clinical differentiation of dementing disorder.

For the demented patient, relatively accurate bedside diagnosis is feasible by use of a carefully designed neurologic examination coupled with an understanding of the neuroanatomy of memory and related cognitive processes. Further confirmation of the clinical diagnosis by the application of selected laboratory diagnostic procedures can then result in an appropriate plan of treatment. With the promise of continued development of new therapeutic modalities for specific dementing illnesses such as Alzheimer's disease, a parallel improvement in diagnostic precision seems mandatory in order to permit detection of the disease at an earlier stage. A clinical anatomic approach with special emphasis on the understanding and assessment of memory function is suggested as a starting point. It is hoped that the serial examination of a significant number of patients by this method will eventually yield clues to aid in the earlier differential diagnosis of dementia.