Pierce Jordan E, Wig Gagan S, Harp Nicholas R, Neta Maital
Center for Brain, Biology, and Behavior, University of Nebraska-Lincoln, Lincoln, NE, United States.
Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, United States.
Imaging Neurosci (Camb). 2024 Dec 19;2. doi: 10.1162/imag_a_00403. eCollection 2024.
The brain is organized into intrinsically connected functional networks that can be reliably identified during resting-state functional magnetic resonance imaging (fMRI). Healthy aging is marked by decreased network segregation, which is linked to worse cognitive functioning, but aging-related changes in emotion are less well characterized. Valence bias, which represents the tendency to interpret emotionally ambiguous information as positive or negative, is more positive in older than younger adults and is associated with differences in task-based fMRI activation in the amygdala, prefrontal cortex, and a cingulo-opercular (CO) network. Here, we examined valence bias, age, and resting-state network segregation of 12 brain networks in a sample of 221 healthy individuals from 6 to 80 years old. Resting-state network segregation decreased linearly with increasing age, extending prior reports of de-differentiation across the lifespan. Critically, a more positive valence bias was related to lower segregation of the default mode network (DMN), due to stronger functional connectivity of the DMN with CO and, to a lesser extent, the ventral attention network (VAN) in all participants. In contrast to this overall segregation effect, in participants over 39 years old (who tend to show a positive valence bias), bias was also related toconnectivity between the DMN and Reward networks. The present findings indicate that specific interactions between the DMN, a task control network (CO), an emotion processing network (Reward), and, to a weaker extent, an attention network (VAN), support a more positive valence bias, perhaps through regulatory control of self-referential processing and reduced emotional reactivity in aging. The current work offers further insight into the functional brain network alterations that may contribute to affective well-being and dysfunction across the lifespan.
大脑被组织成内在连接的功能网络，在静息态功能磁共振成像（fMRI）期间可以可靠地识别这些网络。健康衰老的特征是网络分离减少，这与较差的认知功能有关，但与衰老相关的情绪变化的特征尚不明确。效价偏差代表将情绪模糊信息解释为积极或消极的倾向，在老年人中比年轻人更积极，并且与杏仁核、前额叶皮层和扣带回-岛盖（CO）网络中基于任务的fMRI激活差异有关。在这里，我们在221名6至80岁的健康个体样本中，研究了12个脑网络的效价偏差、年龄和静息态网络分离情况。静息态网络分离随着年龄的增长呈线性下降，扩展了先前关于整个生命周期去分化的报道。至关重要的是，在所有参与者中，更积极的效价偏差与默认模式网络（DMN）的较低分离有关，这是由于DMN与CO以及在较小程度上与腹侧注意网络（VAN）之间更强的功能连接。与这种整体分离效应相反，在39岁以上的参与者（他们倾向于表现出正性效价偏差）中，偏差也与DMN和奖赏网络之间的连接有关。目前的研究结果表明，DMN、任务控制网络（CO）、情绪处理网络（奖赏）以及在较弱程度上注意网络（VAN）之间的特定相互作用，可能通过对自我参照加工的调节控制和降低衰老过程中的情绪反应性，支持更积极的效价偏差。当前的工作进一步深入了解了可能导致整个生命周期情感幸福感和功能障碍的功能性脑网络改变。
