The Semantic Object Retrieval Test (SORT) in amnestic mild cognitive impairment.
BACKGROUND
Between 10% and 15% of patients with the amnestic variety of Mild Cognitive Impairment (MCI) convert to Alzheimer disease (AD) per year.


OBJECTIVE
Characterize cognitive markers that may herald conversion from MCI to AD and directly assess semantic memory in patients meeting criteria for amnestic MCI.


METHODS
Thirty-five amnestic MCI patients and 121 healthy aging controls enrolled at an Alzheimer Disease Center received a battery of standard neuropsychologic tests, and the Semantic Object Retrieval Test (SORT), a test that we have developed for the assessment of semantic memory and subsequent name production, and that has been shown to be able to differentiate between normals and patients with AD.


RESULTS
On the basis of normative data from the SORT, the MCI subjects could be divided into 2 groups: 10 patients (29%) with a significant semantic impairment (SI+) and 25 without a semantic memory deficit (SI-). There was a significant correlation between all SORT variables and performance on the Boston Naming Test. In this MCI population, significantly impaired SORT performance was associated with a relative decrease in performance on tests of frontal lobe functions, although disruption of thalamic-related processes cannot be excluded as an etiology for semantic memory impairment.


CONCLUSIONS
The SORT is a specific test of semantic memory, and is a sensitive measure of semantic memory deficits in patients who otherwise meet criteria for amnestic MCI. Using this specific assessment tool, a significant number of MCI patients were found to have semantic memory deficits. As these patients may be early in the course of possible progression toward dementia, the SORT or other tests of semantic memory may provide important diagnostic or prognostic information in patients with MCI.
Kraut
Michael A
MA
Department of Radiology, Division of Neuroradiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Cherry
Barbara
B
Pitcock
Jeffery A
JA
Anand
Raksha
R
Li
Juan
J
Vestal
Lindsey
L
Henderson
Victor W
VW
Hart
John
J
D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D003704:Dementia / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D007807:Language Tests; D008297:Male; D008569:Memory Disorders / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D012016:Reference Values; D012307:Risk Factors; D012660:Semantics; D012720:Severity of Illness Index; D014706:Verbal Learning / Q000502:physiology