دانلود رایگان مقاله نقش زیر شاخه ناحیه هیپوکامپ در حافظه اپیزودیک کلامی و بصری

ABSTRACT

Introduction: Selective hippocampal (HC) subfield atrophy has been reported in older adults with mild cognitive impairment and Alzheimer’s disease. The goal of this study was to investigate the associations between the volume of hippocampal subfields and visual and verbal episodic memory in cognitively normal older adults. Methods: This study was conducted on a subset of 133 participants from the Einstein Aging Study (EAS), a community-based study of non-demented older adults systematically recruited from the Bronx, N.Y. All participants completed comprehensive EAS neuropsychological assessment. Visual episodic memory was assessed using the Complex Figure Delayed Recall subtest from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Verbal episodic memory was assessed using Delayed Recall from the Free and Cued Selective Reminding Test (FCSRT). All participants underwent 3T MRI brain scanning with subsequent automatic measurement of the hemispheric hippocampal subfield volumes (CA1, CA2- CA3,CA4-dente gyrus, presubiculum, and subiculum).We used linear regressions tomodel the association between hippocampal subfield volumes and visual and verbal episodic memory tests while adjusting for age, sex, education, and total intracranial volume. Results: Participants had a mean age of 78.9 (SD = 5.1) and 60.2% were female. Total hippocampal volume was associated with Complex Figure Delayed Recall ( = 0.31, p = 0.001) and FCSRT Delayed Recall ( = 0.27, p = 0.007); subiculum volume was associated with Complex Figure Delayed Recall ( = 0.27, p = 0.002) and FCSRT Delayed Recall ( = 0.24, p = 0.010); CA1 was associated with Complex Figure Delayed Recall ( = 0.26, p < 0.002) and FCSRT Delayed Recall ( = 0.20, p = 0.025). Conclusions: Our findings confirm previous research on the specific roles of CA1 and subiculum in episodic memory. Our results suggest that hippocampal subfields have sensitive roles in the process of visual and verbal episodic memory. © 20

5. Conclusion

In this study we explored associations between delayed visual and verbal recallmeasures using theRBANS Complex Figure subtest and the FCSRT Delayed Recall subtest and hippocampal sub-regions in healthy older adults. Our results showed CA1 and subiculum sub- fields as strongly associated with both verbal and visual episodic memory. Our results suggested that hippocampal atrophy, specifically, CA1 and subiculum may be markers of normative cognitive decline, and thattheR-BANS Complex Figure and the FCSRT delayed recall may provide quick, sensitive insights into the aging brain and its cognitive function. Our results offer clinical applicability by encouraging the use of these neurocognitive tests as prognostic measures in clinical settings to encourage watchful waiting in individuals whose scores are below age-adjusted means, and thus denote risk or even possible impairment, in which case a more active approach and thorough assessment that resorts to imaging procedures as a confirmatory approach for diagnosis may proceed. We suggest future research to use these and other psychometric tests to aid in developing a better understanding of the hippocampus, its subfields, and their functions relating to cognition in humans.