Cognitive Neuroscience Laboratory, Shirley Ryan AbilityLab, Chicago, IL, USA.
Cognitive Neuroscience Laboratory, Shirley Ryan AbilityLab, Chicago, IL, USA.
Neuropsychologia. 2017 Dec;107:68-75. doi: 10.1016/j.neuropsychologia.2017.11.007. Epub 2017 Nov 7.
Machiavellianism - a personality trait that is characterized by a tendency to distrust, deceive and exploit others - has been the focus of growing attention in psychological research. Neuroimaging studies of Machiavellianism highlight the influence of the dorsolateral prefrontal cortex (dlPFC) on Machiavellianism tendencies. However, knowledge regarding the causal role of the left and right dlPFC on Machiavellianism is still obscure. Here, we measured general Machiavellian tendencies, as well as two subscales (i.e., Machiavellian Views and Machiavellian Tactics) in a large sample of brain-injured patients (N = 129) and non-brain-injured control participants (N = 37) to determine whether Machiavellianism tendencies can be altered by brain damage. We analyzed Machiavellianism tendencies as a function of lesion location, with patients separated into four groups based on dlPFC damage: left dlPFC damage, right dlPFC damage, non-dlPFC damage, and healthy controls. We found that left dlPFC damage increased Machiavellianism in general, and Machiavellian perspective (views) in particular, but did not modulate behavior (tactics). Critically, left dlPFC damage predicted higher levels of Machiavellianism after controlling for general and emotional intelligence, linguistic abilities, empathy and psychopathology. These findings establish a causal role of the left dlPFC in modulating Machiavellian views, and indicate that one can hold Machiavellian views without necessarily endorsing Machiavellian tactics.
马基雅维利主义——一种以不信任、欺骗和利用他人为特征的人格特质——一直是心理学研究关注的焦点。马基雅维利主义的神经影像学研究强调了背外侧前额叶皮层（dlPFC）对马基雅维利主义倾向的影响。然而，关于左、右 dlPFC 对马基雅维利主义的因果作用的知识仍然不清楚。在这里，我们在一个大样本的脑损伤患者（N=129）和非脑损伤对照组参与者（N=37）中测量了一般马基雅维利主义倾向，以及两个亚量表（即马基雅维利主义观点和马基雅维利主义策略），以确定马基雅维利主义倾向是否可以通过脑损伤改变。我们分析了马基雅维利主义倾向作为病变位置的函数，将患者分为四组，基于 dlPFC 损伤：左 dlPFC 损伤、右 dlPFC 损伤、非 dlPFC 损伤和健康对照组。我们发现，左 dlPFC 损伤总体上增加了马基雅维利主义，特别是马基雅维利主义观点（观点），但没有调节行为（策略）。关键的是，在控制一般和情绪智力、语言能力、同理心和精神病理学后，左 dlPFC 损伤预测了更高水平的马基雅维利主义。这些发现确立了左 dlPFC 在调节马基雅维利主义观点方面的因果作用，并表明一个人可以持有马基雅维利主义观点，而不一定赞同马基雅维利主义策略。
