Differences in the memory characteristics of patients with Alzheimer's disease (AD), Huntington's disease (HD), and Parkinson's disease (PD) were investigated with tests that assess learning and retention of words, line-drawn objects, and locations. Large groups of AD, HD, and PD patients were administered the Hopkins Verbal Learning Test-Revised (HVLT-R) and the Hopkins Board (HB). Eight learning and memory measures were subjected to discriminant function analysis. A 91% classification accuracy was achieved for the separation of cortical and subcortical dementias and 79% accuracy for the discrimination of the three groups. The delayed recall of items was the best discriminator. Receiver-operating curve analysis indicated up to 90% sensitivity and 90% specificity in differentiating the three diseases using the discriminant scores. Individual learning and memory measures of the HVLT-R and the HB provided very high sensitivity and specificity in distinguishing cortical versus subcortical dementias and modest accuracy in separating the two subcortical diseases.