The Semantic Object Retrieval Test (SORT) in normal aging and Alzheimer disease.

OBJECTIVE: To characterize performance on a test of semantic object retrieval (Semantic Object Retrieval Test-SORT) in healthy, elderly subjects and patients with Alzheimer disease (AD).

BACKGROUND: Although the initial presentation of patients with AD often reflects impairment in delayed recall for verbally encoded memory, common complaints of patients with early AD are actually related to semantic memory impairment.

DESIGN: Thirty-eight AD patients and 121 healthy aging controls enrolled in an Alzheimer's Disease Center received a battery of standard neuropsychologic tests including the SORT.

RESULTS: Compared with normal controls, AD patients had SORT memory impairments with significantly more false positive memory errors, fewer correctly produced names, and more substitutions in the name production aspect of the test. SORT had robust test-retest reliability in normals.

CONCLUSIONS: The SORT task provides a direct, specific assessment of semantic memory, and has now been administered to 121 healthy, aging controls for normative ranges of performance, and to AD patients. The task detected semantic memory deficits in approximately half of patients with mild-moderate AD, which is comparable to other studies assessing semantic deficits in AD with less specific measures.