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Amnestic mild cognitive impairment represents an early stage of Alzheimer's disease, and characterization of physiological alterations in mild cognitive impairment is an important step toward accurate diagnosis and intervention of this condition. To investigate the extent of neurodegeneration in patients with mild cognitive impairment, whole-brain cerebral metabolic rate of oxygen in absolute units of µmol O 2 /min/100 g was quantified in 44 amnestic mild cognitive impairment and 28 elderly controls using a novel, non-invasive magnetic resonance imaging method. We found a 12.9% reduction ( p = 0.004) in cerebral metabolic rate of oxygen in mild cognitive impairment, which was primarily attributed to a reduction in the oxygen extraction fraction, by 10% ( p = 0.016). Global cerebral blood flow was not found to be different between groups. Another aspect of vascular function, cerebrovascular reactivity, was measured by CO 2 -inhalation magnetic resonance imaging and was found to be equivalent between groups. Therefore, there seems to be a global, diffuse diminishment in neural function in mild cognitive impairment, while their vascular function did not show a significant reduction.

This investigation examined the relationship of the word list from the CERAD neuropsychological battery to the California Verbal Learning Test (CVLT) in a sample of 138 subjects with Probable Alzheimer's disease (AD). Results revealed modest but statistically significant associations between the two measures on many key variables. Total words learned showed the strongest association, with lower correlations for delayed recall, intrusion errors, and recognition variables. As expected, the CERAD and CVLT assess similar aspects of verbal learning in patients with AD. However, the modest level of many of the correlations suggests that caution should be exercised in applying the same interpretive strategies derived on more comprehensive measures to shorter ones.