This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Background: Characterization of the behavioral correlates of neuromorphometry and neurochemistry in older adults has important implications for an improved understanding of the aging process. The objective of this study was to test the hypothesis that a measure of hippocampal neuronal metabolism was associated with verbal memory in nondemented older adults after controlling for hippocampal volume.
Methods: 4-T MRI, proton magnetic resonance spectroscopy (1H MRS), and neuropsychological assessment were conducted in 48 older adults (23 women; mean age 81 years). Average hippocampal N-acetyl aspartate/creatine ratios (NAA/Cr) and hippocampal volumes were obtained. Neuropsychological evaluation included tests of verbal memory (Buschke and Grober Free and Cued Selective Reminding Test–Immediate Recall [FCSRT-IR], Wechsler Memory Scale–Revised Logical Memory subtest) and attention and executive function (Trail Making Test Parts A and B).
Results: Linear regression analysis indicated that after adjusting for age, hippocampal NAA/Cr was a significant predictor of FCSRT-IR performance (β = 0.38, p = 0.01, R 2 = 0.21). Hippocampal volume was also a significant predictor of FCSRT-IR performance after adjusting for age and midsagittal area (β = 0.47, p = 0.01, R 2 = 0.24). In a combined model, hippocampal NAA/Cr (β = 0.33, p = 0.03) and volume (β = 0.35, p = 0.03) were independent predictors of FCSRT-IR performance, accounting for 30% of the variance in memory.
Conclusions: These findings indicate that nondemented older adults with smaller hippocampal volumes and lower levels of hippocampal N-acetyl aspartate/creatine ratio metabolites perform more poorly on a test of verbal memory. The integrity of both the structure and metabolism of the hippocampus may underlie verbal memory function in nondemented elderly.
GLOSSARY: BIMC = Blessed Information-Memory-Concentration test; CDR = Clinical Dementia Rating scale; EAS = Einstein Aging Study; FCSRT-IR = Buschke and Grober Free and Cued Selective Reminding Test–Immediate Recall; FOV = field of view; LM = Wechsler Memory Scale–Revised Logical Memory subtest; MCI = mild cognitive impairment; MR = magnetic resonance; MRS = magnetic resonance spectroscopy; NAA/Cr = N-acetyl aspartate/creatine ratio; TMTA = Trail Making Test Part A; TMTB = Trail Making Test Part B.
AAN Members
We have changed the login procedure to improve access between AAN.com and the Neurology journals. If you are experiencing issues, please log out of AAN.com and clear history and cookies. (For instructions by browser, please click the instruction pages below). After clearing, choose preferred Journal and select login for AAN Members. You will be redirected to a login page where you can log in with your AAN ID number and password. When you are returned to the Journal, your name should appear at the top right of the page.
AAN Non-Member Subscribers
Purchase access
Letters: Rapid online correspondence
REQUIREMENTS
You must ensure that your Disclosures have been updated within the previous six months. Please go to our Submission Site to add or update your Disclosure information.
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.
