ASSESSMENT OF ASSOCIATIVE RELATIONS IN ALZHEIMERS-DISEASE - EVIDENCE FOR PRESERVATION OF SEMANTIC MEMORY

Semantic priming was assessed in Alzheimer's disease (AD), elderly con trol, and young control subjects with three lexical decision, continuo us priming experiments. The stimuli were intracategory, associated pai rs in Experiments 1 and 2 and varied types of associated pairs in Expe riment 3. AD priming effects were equal to those of elderly control su bjects; elderly and young control priming effects were also equal. We interpret this as evidence for the relative preservation of the semant ic memory network in early AD, as in normal aging, at least to the ext ent necessary for normal access of concept nodes and normal automatic spreading activation between concept nodes. In a final study (Experime nt 4) knowledge of the associations between the targets and related pr imes used in Experiments 1 and 2 was explicitly assessed; 20 out of 22 AD subjects showed perfect or close to perfect performance.