EXPLORING VISUOSPATIAL SHORT-TERM-MEMORY DEFECT IN ALZHEIMERS-DISEASE

The present study aimed at controlling two variables that may affect t he visuospatial short-term memory of Alzheimer patients: visuospatial coding efficiency and response modality. Thirty patients affected by A lzheimer-type dementia with relatively spared visuo-perceptual functio ns were tested under three conditions, all of which employed the same kind of stimuli (visuospatial patterns). At all memory tasks, patients achieved scores significantly lower than those of 30 age- and educati on-matched normal subjects. Patients did not benefit from longer prese ntation time, nor did their performance improve with pointing response modality, although they performed perceptual pattern recognition as w ell as did controls. These data confirm that visuospatial immediate me mory capacity is reduced in dementia.