Ren Ping, Anthony Mia, Chapman Benjamin P, Heffner Kathi, Lin Feng
School of Nursing, University of Rochester Medical Center, Rochester, NY, USA.
Department of Psychiatry, University of Rochester Medical Center, Rochester, NY, USA; Depart of Public Health Science, University of Rochester Medical Center, Rochester, NY, USA.
Neuropsychologia. 2017 May;99:199-206. doi: 10.1016/j.neuropsychologia.2017.03.016. Epub 2017 Mar 14.
Locus of control (LOC) measures the extent to which individuals perceive control over their lives. Those with a more "internal" LOC feel self-sufficient and able to determine important aspects of their own future, while those with a more "external" LOC feel that their lives are governed by events beyond their control. Reduced internal LOC and increased external LOC have been found in cognitive disorders, but the neural substrates of these control perceptions are yet unknown. In the present study, we explored the relationship between amygdala functional connectivity and LOC in 18 amnestic mild cognitive impairment (MCI) and age-, sex-, and education-matched, 22 cognitively healthy controls (HC). Participants completed cognitive challenge tasks (Stroop Word Color task and Dual 1-back) for 20min, and underwent resting-state functional magnetic resonance imaging immediately before and after the tasks. We found significantly lower internal LOC and higher external LOC in the MCI group than the HC group. Compared to HC, MCI group showed significantly stronger positive associations between internal LOC and baseline right amygdala connections (including right middle frontal gyrus and anterior cingulate cortex), and stronger negative associations between internal LOC and change of these right amygdala connections. Across all participants, external LOC explained the relationships between associations of another set of right amygdala connections (including middle cingulate cortex and right superior frontal gyrus), both at baseline and for change, and performance in the cognitive challenge tasks. Our findings indicate that the right amygdala networks might be critical in understanding the neural mechanisms underlying LOC's role in cognitive aging.
控制点(LOC)衡量个体感知对自己生活控制程度的高低。具有更“内控型”LOC的人感到自给自足,能够决定自己未来的重要方面,而具有更“外控型”LOC的人则觉得他们的生活受自身无法控制的事件支配。在认知障碍中已发现内控型LOC降低和外控型LOC增加的情况,但这些控制感知的神经基础尚不清楚。在本研究中,我们探讨了18名遗忘型轻度认知障碍(MCI)患者以及年龄、性别和教育程度匹配的22名认知健康对照者(HC)的杏仁核功能连接与LOC之间的关系。参与者完成了20分钟的认知挑战任务(斯特鲁普文字颜色任务和双重1-back任务),并在任务前后立即进行静息态功能磁共振成像。我们发现MCI组的内控型LOC显著低于HC组,外控型LOC显著高于HC组。与HC相比,MCI组在内控型LOC与基线右侧杏仁核连接(包括右侧额中回和前扣带回皮质)之间显示出显著更强的正相关,在内控型LOC与这些右侧杏仁核连接的变化之间显示出更强的负相关。在所有参与者中,外控型LOC解释了另一组右侧杏仁核连接(包括扣带中部皮质和右侧额上回)在基线和变化时的关联与认知挑战任务表现之间的关系。我们的研究结果表明,右侧杏仁核网络可能在理解LOC在认知衰老中作用的神经机制方面至关重要。