Department of Radiation Sciences, Umeå University, Umeå, Sweden; Department of Integrative Medical Biology, Umeå University, Umeå, Sweden; Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden; UiO Center for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, Oslo, Norway.
German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.
Neurobiol Aging. 2020 Oct;94:217-226. doi: 10.1016/j.neurobiolaging.2020.06.005. Epub 2020 Jun 12.
Heterogeneity in episodic memory functioning in aging was assessed with a pattern-completion functional magnetic resonance imaging task that required reactivation of well-consolidated face-name memory traces from fragmented (partial) or morphed (noisy) face cues. About half of the examined individuals (N = 101) showed impaired (chance) performance on fragmented faces despite intact performance on complete and morphed faces, and they did not show a pattern-completion response in hippocampus or the examined subfields (CA1, CA23, DGCA4). This apparent pattern-completion deficit could not be explained by differential hippocampal atrophy. Instead, the impaired group displayed lower cortical volumes, accelerated reduction in mini-mental state examination scores, and lower general cognitive function as defined by longitudinal measures of visuospatial functioning and speed-of-processing. In the full sample, inter-individual differences in visuospatial functioning predicted performance on fragmented faces and hippocampal CA23 subfield activity over 25 years. These findings suggest that visuospatial functioning in middle age can forecast pattern-completion deficits in aging.
采用模式完成功能磁共振成像任务来评估衰老过程中情景记忆功能的异质性,该任务要求从碎片化(部分)或变形(嘈杂)的面部提示中重新激活已充分巩固的面孔-名字记忆痕迹。大约一半的被检查个体(N=101)在碎片化面孔上表现出受损(随机)的表现,尽管在完整和变形面孔上表现正常,并且他们在海马体或检查的亚区(CA1、CA23、DGCA4)中没有表现出模式完成反应。这种明显的模式完成缺陷不能用海马体萎缩的差异来解释。相反,受损组显示出较低的皮质体积、简易精神状态检查评分的加速降低以及较低的一般认知功能,这是通过纵向测量视空间功能和处理速度来定义的。在整个样本中,视空间功能的个体差异可以预测 25 年内对碎片化面孔的表现和海马体 CA23 亚区的活动。这些发现表明,中年时的视空间功能可以预测衰老过程中的模式完成缺陷。