Analysis of verbal memory and learning by means of selective reminding procedure in Alzheimer and multi-infarct dementias

Abstract

Several studies aimed at defining the characteristics of memory impairment resulting from different etiologic forms of dementia have been inconclusive. These unsatisfactory results might be due to the enrollment of various groups of demented patients not matched for disease severity, as well as the use of different psychometric procedures. The object of the present study was to verify the existence of a different pattern of verbal memory impairment that might be useful in clinical practice in two groups of AD and MID patients who were matched for degree of cognitive deterioration. Thirty-seven AD and 41 MID patients were assessed for memory and learning by means of the Supraspan Verbal Learning test (Selective Reminding by Buschke-Fuld), which provides a simultaneous analysis of storage, retention and retrieval abilities. Twenty-four normal subjects were studied as a control group. No differences in storage and retrieval mean scores were found between the two groups. AD patients showed a higher mean score in random retrieval; the mean score in selective retrieval at the end of learning was significantly higher in MID patients, suggesting a more impaired retrieval from long-term storage in AD than in MID patients. Intrusions, defined as inappropriate recurrences from preceding tests, were observed more frequently in AD patients. The presence of intrusions and the delayed retrieval score showed a good level of sensitivity and specificity in the differential diagnosis between the two groups.