Bahri Maryam, Farrahi Hassan, Mahdavinataj Hami, Batouli Seyed Amir Hossein
Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Kavosh Cognitive Behavior Sciences and Addiction Research Center, Department of Psychiatry, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
Front Psychol. 2024 Sep 3;15:1377342. doi: 10.3389/fpsyg.2024.1377342. eCollection 2024.
Working memory (WM) as one of the executive functions is an essential neurocognitive ability for daily life. Findings have suggested that aging is often associated with working memory and neural decline, but the brain structures and resting-state brain networks that mediate age-related differences in WM remain unclear.
A sample consisting of 252 healthy participants in the age range of 20 to 70years was used. Several cognitive tasks, including the n-back task and the forward and backward digit span tests were used. Also, resting-state functional imaging, as well as structural imaging using a 3T MRI scanner, were performed, resulting in 85 gray matter volumes and five resting-state networks, namely the anterior and posterior default mode, the right and left executive control, and the salience networks. Also, mediation analyses were used to investigate the role of gray matter volumes and resting-state networks in the relationship between age and WM.
Behaviorally, aging was associated with decreased performance in the digit span task. Also, aging was associated with a decreased gray matter volume in 80 brain regions, and with a decreased activity in the anterior default mode network, executive control, and salience networks. Importantly, the path analysis showed that the GMV of the medial orbitofrontal, precentral, parieto-occipital, amygdala, middle occipital, posterior cingulate, and thalamus areas mediated the age-related differences in the forward digit span task, and the GMV of superior temporal gyrus mediated the age-related differences in the backward digit span task.
This study identified the brain structures mediating the relationship between age and working memory, and we hope that our research provides an opportunity for early detection of individuals at risk of age-related memory decline.
工作记忆作为执行功能之一，是日常生活中一项重要的神经认知能力。研究结果表明，衰老通常与工作记忆和神经衰退有关，但介导工作记忆中与年龄相关差异的脑结构和静息态脑网络仍不清楚。
使用了一个由252名年龄在20至70岁之间的健康参与者组成的样本。采用了几种认知任务，包括n-back任务以及顺背和倒背数字广度测试。此外，还进行了静息态功能成像以及使用3T MRI扫描仪的结构成像，得到了85个灰质体积和五个静息态网络，即前后默认模式、左右执行控制和突显网络。同时，采用中介分析来研究灰质体积和静息态网络在年龄与工作记忆关系中的作用。
在行为方面，衰老与数字广度任务表现下降有关。此外，衰老与80个脑区的灰质体积减少以及前默认模式网络、执行控制网络和突显网络的活动减少有关。重要的是，路径分析表明，内侧眶额、中央前回、顶枕叶、杏仁核、枕中回、后扣带回和丘脑区域的灰质体积介导了顺背数字广度任务中与年龄相关的差异，颞上回的灰质体积介导了倒背数字广度任务中与年龄相关的差异。
本研究确定了介导年龄与工作记忆关系的脑结构，我们希望我们的研究为早期发现有年龄相关记忆衰退风险的个体提供机会。
