Memory Modulation Factors in Hippocampus Exposed to Radiation.

IF 1.1 Q4 MEDICINE, RESEARCH & EXPERIMENTAL
Sovremennye Tehnologii v Medicine Pub Date : 2021-01-01 Epub Date: 2021-08-28 DOI:10.17691/stm2021.13.4.01
O A Krotkova, A Y Kuleva, M V Galkin, M Y Kaverina, Y V Strunina, G V Danilov
{"title":"Memory Modulation Factors in Hippocampus Exposed to Radiation.","authors":"O A Krotkova,&nbsp;A Y Kuleva,&nbsp;M V Galkin,&nbsp;M Y Kaverina,&nbsp;Y V Strunina,&nbsp;G V Danilov","doi":"10.17691/stm2021.13.4.01","DOIUrl":null,"url":null,"abstract":"<p><p>Although the key scene of the hippocampus in memory processes is obvious, the specificity of its participation in information processing is far from being established. Current advanced neuroimaging enables to operate with precise morphometric parameters. <b>The aim of the study</b> was to reveal fine memory rearrangements under mechanical impact on the hippocampus by a neoplasm and radiation exposure in the course of therapy.</p><p><strong>Materials and methods: </strong>We used a homogeneous sample of 28 patients with parasellar meningiomas adjacent to hippocampus. In 10 patients (5 with left-sided and 5 with right-sided meningiomas), the tumor was located near the hippocampus but exhibited no mechanical effect on it. In 18 patients (10 with left-sided and 8 with right-sided tumors), the neoplasm compressed the adjacent hippocampus. The control group consisted of 39 healthy subjects. All three groups were comparable in age, education, and gender characteristics. In order to control tumor growth, the patients underwent radiotherapy when the hippocampus involuntary was exposed to a dose comparable to that in the tumor (30 sessions with a single focal dose of 1.8 Gy, total dose - 54.0 Gy).Based on the literature data on hippocampus involved in mnestic processes, a special methodology to investigate memory was developed. Incorrect responses the subjects made when identifying previously memorized images were classified as neutralizing the novelty factor of an identified stimulus or as wrongly emphasizing its novelty.</p><p><strong>Results: </strong>At the first observation point (before radiation therapy) all groups underwent a complete standardized neuropsychological examination and performed a battery of cognitive tests. The overall results of the tests assessing attention, memory, thinking processes, and neurodynamic indicators corresponded to standard values. A mild brain compression by the tumor without brain tissue destruction was not accompanied by focal neuropsychological symptoms and deficit manifestations in the cognitive sphere. However, as early as in the first observation point, the number of \"pattern separation\" errors in the clinical group was significantly higher than that in healthy subjects.The second observation point (immediately after radiotherapy) and the third observation point - 6 months after the treatment - showed that, in general, the patients' cognitive sphere condition was not deteriorating, and in a number of parameters was characterized by positive dynamics, apparently associated with some tumor reduction due to the therapy provided. However, the distribution of errors in the original method significantly changed. When previously memorized stimuli were recognized, the errors neutralizing the novelty factor of the evaluated stimulus increased, while the number of errors with overestimating the stimuli novelty decreased.All tendencies hypothetically (according to the published data) associated with the changes in functional activity of the hippocampus were more pronounced in the subgroup of patients with mechanical impact of the tumor on hippocampus.</p><p><strong>Conclusion: </strong>The continuous flow of impressions any person has at any moment of his activity is most likely marked by the hippocampus in a continuum \"old-similar-new\". The present study has shown that mechanical impact on the hippocampus combined with radiation exposure changes the range of assessments towards the prevailing labeling \"old, previously seen, already known\".</p>","PeriodicalId":51886,"journal":{"name":"Sovremennye Tehnologii v Medicine","volume":"13 4","pages":"6-13"},"PeriodicalIF":1.1000,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8482834/pdf/","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Sovremennye Tehnologii v Medicine","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.17691/stm2021.13.4.01","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2021/8/28 0:00:00","PubModel":"Epub","JCR":"Q4","JCRName":"MEDICINE, RESEARCH & EXPERIMENTAL","Score":null,"Total":0}
引用次数: 1

Abstract

Although the key scene of the hippocampus in memory processes is obvious, the specificity of its participation in information processing is far from being established. Current advanced neuroimaging enables to operate with precise morphometric parameters. The aim of the study was to reveal fine memory rearrangements under mechanical impact on the hippocampus by a neoplasm and radiation exposure in the course of therapy.

Materials and methods: We used a homogeneous sample of 28 patients with parasellar meningiomas adjacent to hippocampus. In 10 patients (5 with left-sided and 5 with right-sided meningiomas), the tumor was located near the hippocampus but exhibited no mechanical effect on it. In 18 patients (10 with left-sided and 8 with right-sided tumors), the neoplasm compressed the adjacent hippocampus. The control group consisted of 39 healthy subjects. All three groups were comparable in age, education, and gender characteristics. In order to control tumor growth, the patients underwent radiotherapy when the hippocampus involuntary was exposed to a dose comparable to that in the tumor (30 sessions with a single focal dose of 1.8 Gy, total dose - 54.0 Gy).Based on the literature data on hippocampus involved in mnestic processes, a special methodology to investigate memory was developed. Incorrect responses the subjects made when identifying previously memorized images were classified as neutralizing the novelty factor of an identified stimulus or as wrongly emphasizing its novelty.

Results: At the first observation point (before radiation therapy) all groups underwent a complete standardized neuropsychological examination and performed a battery of cognitive tests. The overall results of the tests assessing attention, memory, thinking processes, and neurodynamic indicators corresponded to standard values. A mild brain compression by the tumor without brain tissue destruction was not accompanied by focal neuropsychological symptoms and deficit manifestations in the cognitive sphere. However, as early as in the first observation point, the number of "pattern separation" errors in the clinical group was significantly higher than that in healthy subjects.The second observation point (immediately after radiotherapy) and the third observation point - 6 months after the treatment - showed that, in general, the patients' cognitive sphere condition was not deteriorating, and in a number of parameters was characterized by positive dynamics, apparently associated with some tumor reduction due to the therapy provided. However, the distribution of errors in the original method significantly changed. When previously memorized stimuli were recognized, the errors neutralizing the novelty factor of the evaluated stimulus increased, while the number of errors with overestimating the stimuli novelty decreased.All tendencies hypothetically (according to the published data) associated with the changes in functional activity of the hippocampus were more pronounced in the subgroup of patients with mechanical impact of the tumor on hippocampus.

Conclusion: The continuous flow of impressions any person has at any moment of his activity is most likely marked by the hippocampus in a continuum "old-similar-new". The present study has shown that mechanical impact on the hippocampus combined with radiation exposure changes the range of assessments towards the prevailing labeling "old, previously seen, already known".

Abstract Image

Abstract Image

Abstract Image

辐射照射下海马记忆调节因子的研究。
虽然海马体在记忆过程中的关键场景是显而易见的,但其参与信息加工的特异性还远未确定。目前先进的神经成像技术能够精确地进行形态学参数的操作。该研究的目的是揭示在治疗过程中肿瘤和辐射暴露对海马体的机械影响下的精细记忆重排。材料和方法:我们使用了28例邻近海马的鞍旁脑膜瘤患者的均匀样本。在10例患者(5例左侧脑膜瘤,5例右侧脑膜瘤)中,肿瘤位于海马附近,但未对其产生机械作用。在18例患者中(10例左侧肿瘤,8例右侧肿瘤),肿瘤压迫邻近的海马。对照组为39名健康受试者。这三组在年龄、教育程度和性别特征上具有可比性。为了控制肿瘤生长,患者接受了与肿瘤相当剂量的海马非自愿放射治疗(30次,单局剂量1.8 Gy,总剂量- 54.0 Gy)。在文献资料的基础上,提出了一种特殊的记忆研究方法。被试在识别先前记忆的图像时做出的错误反应被归类为抵消已识别刺激的新颖性因素或错误地强调其新颖性。结果:在第一个观察点(放疗前),所有组均进行了完整的标准化神经心理学检查,并进行了一系列认知测试。评估注意力、记忆、思维过程和神经动力学指标的测试总体结果符合标准值。轻度脑压迫肿瘤,无脑组织破坏,不伴有局灶性神经心理症状和认知领域的缺陷表现。然而,早在第一个观察点,临床组的“模式分离”错误次数就明显高于健康组。第二个观察点(放疗后立即)和第三个观察点(治疗后6个月)显示,总体而言,患者的认知领域状况没有恶化,并且在许多参数中具有积极的动态特征,显然与治疗提供的肿瘤减少有关。但是,原方法的误差分布发生了明显变化。当先前记忆的刺激被识别时,抵消被评估刺激新颖性因素的错误增加,而高估刺激新颖性因素的错误减少。所有假设(根据已发表的数据)与海马体功能活动变化相关的趋势在肿瘤对海马体产生机械影响的患者亚组中更为明显。结论:任何人在其活动的任何时刻所拥有的连续不断的印象流最有可能被海马体标记为连续的“旧-相似-新”。目前的研究表明,对海马体的机械影响与辐射暴露相结合,改变了对“旧的、以前见过的、已经知道的”这一普遍标签的评估范围。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Sovremennye Tehnologii v Medicine
Sovremennye Tehnologii v Medicine MEDICINE, RESEARCH & EXPERIMENTAL-
CiteScore
1.80
自引率
0.00%
发文量
38
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信