WORKING-MEMORY AND ONLINE SENTENCE COMPREHENSION IN PATIENTS WITH ALZHEIMERS-DISEASE

We examined the ability of patients with dementia of the Alzheimer's t ype (DAT) and normal controls to perform a sentence acceptability judg ment task that required determining the I referent for a reflexive pro noun. Performance on three different sentence types that differed in t erms of syntactic complexity was assessed. Subjects performed the task alone and under two different dual-task conditions which required con tinuous, externally paced responses. DAT patients were move affected t han controls by the dual-task conditions, but were not disproportionat ely impaired on the more complex sentence types. The failure of DAT pa tients to be disproportionately affected on the most complex sentence types in the dual-task conditions provides evidence for the separation of the processing resources that are used in sentence comprehension f rom those involved in other tasks.