Automatic influences of memory in Alzheimer's disease

Automatic and controlled influences of memory were examined in 12 patients with early Alzheimer's disease (AD) and 12 control subjects. The subjects studied a list of words and then received three-letter word stems in three different retrieval tasks. In an indirect memory task (word-stem completion priming), they were asked to produce the first word that came to mind in response to each stem. In an inclusion task, they were required to produce a studied word in response to each stem, and in an exclusion task they were asked to produce a new, unstudied word for each stem. The performance of the subjects with AD was equal in the inclusion and exclusion conditions, showing no evidence of controlled recollection for the studied words, while their automatic memory as well as priming were preserved. The results provide neuropsychological support for the distinction between controlled and automatic memory processes.