Implicit learning in patients with probable Alzheimer's disease.

The purpose of the present study was to determine whether patients with probable Alzheimer's disease (AD) were capable of implicit procedural learning. AD patients and elderly control subjects were given a serial visual reaction time task with an embedded repeating sequence. The AD patients responded more slowly than the controls, but many nonetheless showed learning of the repeating sequence. Patients who failed to learn the sequence were similar in age and overall severity of dementia to those who learned, but they scored lower on some tasks of nonverbal reasoning.