Related Experiment Video
Updated: Jun 8, 2026
Eye Movement Monitoring of Memory
Published on: August 15, 2010
Impaired visual recognition memory in amnestic mild cognitive impairment is associated with mesiotemporal metabolic
Mira Didic1, Jean-Philippe Ranjeva, Emmanuel Barbeau
1Service de Neurologie et de Neuropsychologie, Pôle de neurosciences cliniques, Assistance Publique des Hôpitaux de Marseille, Hôpitaux de la Timone, CMRR PACA Ouest & INSERM U751, Faculté de Médecine, Université de la Méditerranée, Marseille, France. mira.didic@ap-hm.fr
Abstract:
In the early stages of Alzheimer's disease (AD), neurofibrillary tangles develop in the mesial temporal lobe (MTL), first in the anterior subhippocampal (perirhinal/entorhinal) cortex and then in the hippocampal formation. This region plays a key role in visualrecognition memory (VRM). VRM has been reported to be impaired in patients with amnestic mild cognitive impairment (aMCI). The aim of the present study was to determine if an impairment of VRM is associated with metabolic changes in the MTL using magnetic resonance spectroscopic imaging and if evaluating VRM can contribute to the early diagnosis of AD. 28 patients with aMCI and 28 controls underwent a full neuropsychological assessment including an evaluation of VRM using the DMS48. NAA/mIno ratios, reduced in patients with AD and associated with the severity of pathological changes, were determined in the MTL. aMCI-patients were further divided into two subgroups according to their VRM performance. aMCI-patients showed decreased NAA/mIno levels in the right hippocampus compared with controls. aMCI-patients with impaired VRM showed decreased NAA/mIno ratios in the MTL bilaterally, including a region that sampled the left anterior subhippocampal cortex, compared to controls. No changes were found in aMCI patients with normal VRM. Performance on the DMS48 correlated with NAA/mIno levels in the anterior MTL. Clinical 6-year follow-up data (available for 78.6% of the aMCI-patients) indicates that impaired performance on the DMS48 could predict conversion to AD with a sensitivity and specificity of 81.8%. These findings provide further evidence that impaired VRM, as a hallmark of MTL dysfunction, may contribute to the early diagnosis of AD.
Insights
Impaired visual recognition memory (VRM) in mild cognitive impairment is linked to metabolic changes in the mesial temporal lobe (MTL). This VRM test may help predict Alzheimer
Area of Science:
- Neuroscience
- Biochemistry
- Medical Imaging
Background:
- Early Alzheimer's disease (AD) involves neurofibrillary tangles in the mesial temporal lobe (MTL), affecting visual recognition memory (VRM).
- Amnestic mild cognitive impairment (aMCI) patients often exhibit VRM deficits, suggesting early neuropathological changes.
- Metabolic alterations in the MTL are implicated in AD progression, but their direct link to VRM impairment needs further investigation.
Purpose of the Study:
- To investigate the association between VRM impairment and metabolic changes in the MTL in aMCI patients using magnetic resonance spectroscopic imaging (MRSI).
- To assess the potential of VRM evaluation as an early diagnostic tool for Alzheimer's disease (AD).
- To correlate metabolic markers in the MTL with VRM performance and predict future conversion to AD.
Main Methods:
- 28 aMCI patients and 28 controls underwent comprehensive neuropsychological assessment, including VRM evaluation using the DMS48 test.
- Magnetic resonance spectroscopic imaging (MRSI) was employed to measure N-acetylaspartate/myo-inositol (NAA/mIno) ratios in the MTL.
- aMCI patients were subgrouped based on VRM performance; metabolic data were analyzed in relation to VRM scores and clinical follow-up.
Main Results:
- aMCI patients exhibited reduced NAA/mIno ratios in the right hippocampus compared to controls.
- aMCI patients with impaired VRM showed significantly decreased bilateral MTL NAA/mIno ratios, including the anterior subhippocampal cortex.
- DMS48 performance correlated with NAA/mIno levels in the anterior MTL, and impaired VRM predicted conversion to AD with 81.8% accuracy over 6 years.
Conclusions:
- Impaired VRM in aMCI is associated with specific metabolic reductions in the MTL, particularly the anterior subhippocampal cortex.
- VRM deficits serve as a key indicator of MTL dysfunction and may represent an early hallmark of Alzheimer's disease.
- The DMS48 test, by evaluating VRM, shows promise as a predictive tool for early AD diagnosis and monitoring disease progression.
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