Among a population of nursing home patients with a diagnosis of senile dementia of Alzheimer’s type (SDAT), a subgroup was identified who often became lost and wandered even in familiar surroundings. This subgroup differed from the rest of the SDAT patients on tests of parietal function but not on a generalized test of mental status. Thus, wandering in SDAT patients may be an indication of a specific parietal lobe involvement.