van Dam Wessel O, Decker Scott L, Durbin Jeffery S, Vendemia Jennifer M C, Desai Rutvik H
Department of Psychology, University of South Carolina, USA.
Department of Psychology, University of South Carolina, USA.
Neuroimage. 2015 Sep;118:174-82. doi: 10.1016/j.neuroimage.2015.05.017. Epub 2015 May 14.
Working memory (WM) is one of the key constructs in understanding higher-level cognition. We examined whether patterns of activity in the resting state of individual subjects are correlated with their off-line working and short-term memory capabilities. Participants completed a resting-state fMRI scan and off-line working and short-term memory (STM) tests with both verbal and visual materials. We calculated fractional amplitude of low frequency fluctuations (fALFF) from the resting state data, and also computed connectivity between seeds placed in frontal and parietal lobes. Correlating fALFF values with behavioral measures showed that the fALFF values in a widespread fronto-parietal network during rest were positively correlated with a combined memory measure. In addition, STM showed a significant correlation with fALFF within the right angular gyrus and left middle occipital gyrus, whereas WM was correlated with fALFF values within the right IPS and left dorsomedial cerebellar cortex. Furthermore, verbal and visuospatial memory capacities were associated with dissociable patterns of low-frequency fluctuations. Seed-based connectivity showed correlations with the verbal WM measure in the left hemisphere, and with the visual WM measure in the right hemisphere. These findings contribute to our understanding of how differences in spontaneous low-frequency fluctuations at rest are correlated with differences in cognitive performance.
工作记忆（WM）是理解高级认知的关键结构之一。我们研究了个体受试者静息状态下的活动模式是否与其离线工作记忆和短期记忆能力相关。参与者完成了一次静息态功能磁共振成像扫描以及使用言语和视觉材料进行的离线工作记忆和短期记忆（STM）测试。我们从静息状态数据中计算低频波动分数振幅（fALFF），并计算置于额叶和顶叶的种子之间的连通性。将fALFF值与行为测量结果进行关联，结果显示静息期间广泛的额顶网络中的fALFF值与综合记忆测量结果呈正相关。此外，STM与右侧角回和左侧枕中回内的fALFF显著相关，而WM与右侧顶内沟和左侧背内侧小脑皮质内的fALFF值相关。此外，言语和视觉空间记忆能力与低频波动的可分离模式相关。基于种子的连通性显示与左半球的言语WM测量相关，与右半球的视觉WM测量相关。这些发现有助于我们理解静息时自发低频波动的差异如何与认知表现的差异相关。
