Influences of cognitive support on episodic remembering: tracing the process of loss from normal aging to Alzheimer's disease.

Normal older adults, incident Alzheimer's disease (AD) patients, and prevalent AD patients were examined across a 3-year interval in episodic memory tasks that varied in terms of study time, organizability, and retrieval cues. There were marked overall preclinical deficits among the incident AD patients, although these patients were as effective as the normal older adults in utilizing more study time, organizability, and retrieval cues to improve memory at baseline. When these patients were diagnosed with AD at follow-up, they showed negligible gains from increased study time and organizability when memory was assessed with free recall, although they profited from the provision of retrieval cues. This pattern of results was also seen in the prevalent AD patients at both times of measurement. These results indicate that a general impairment of episodic memory may precede reductions in cognitive reserve capacity in the early development of AD.