Matsunaga Masahiro, Kawamichi Hiroaki, Umemura Tomohiro, Hori Reiko, Shibata Eiji, Kobayashi Fumio, Suzuki Kohta, Ishii Keiko, Ohtsubo Yohsuke, Noguchi Yasuki, Ochi Misaki, Yamasue Hidenori, Ohira Hideki
Department of Health and Psychosocial Medicine, Aichi Medical University School of Medicine, Nagakute, Japan.
Division of Cerebral Integration, Department of System Neuroscience, National Institute for Physiological Sciences, Okazaki, Japan.
Front Neurosci. 2017 Dec 19;11:718. doi: 10.3389/fnins.2017.00718. eCollection 2017.
Happiness is regarded as one of the most fundamental human goals. Given recent reports that positive feelings are contagious (e.g., the presence of a happy person enhances others' happiness) because of the human ability to empathize (i.e., sharing emotions), empathic ability may be a key factor in increasing one's own subjective level of happiness. Based on previous studies indicating that a single nucleotide polymorphism in the serotonin 2A receptor gene [ rs6311 guanine (G) vs. adenine (A)] is associated with sensitivity to emotional stimuli and several mental disorders such as depression, we predicted that the polymorphism might be associated with the effect of sharing happiness. To elucidate the neural and genetic correlates of the effect of sharing happiness, we first performed functional magnetic resonance imaging (fMRI) during a "happy feelings" evocation task (emotional event imagination task), during which we manipulated the valence of the imagined event (positive, neutral, or negative), as well as the presence of a friend experiencing a positive-valence event (presence or absence). We recruited young adult women for this fMRI study because empathic ability may be higher in women than in men. Participants felt happier ( < 0.01) and the mentalizing/theory-of-mind network, which spans the medial prefrontal cortex, temporoparietal junction, temporal poles, and precuneus, was significantly more active ( < 0.05) in the presence condition than in the absence condition regardless of event valence. Moreover, participants with the GG ( < 0.01) and AG ( < 0.05) genotypes of experienced happier feelings as well as greater activation of a part of the mentalizing/theory-of-mind network ( < 0.05) during empathy for happiness (neutral/presence condition) than those with the AA genotype. In a follow-up study with a vignette-based questionnaire conducted in a relatively large sample, male and female participants were presented with the same imagined events wherein their valence and the presence of a friend were manipulated. Results showed genetic differences in happiness-related empathy regardless of sex ( < 0.05). Findings suggest that polymorphisms are associated with the effect of sharing happiness by modulating the activity of the mentalizing/theory-of-mind network.
幸福被视为人类最基本的目标之一。鉴于最近有报道称，由于人类的共情能力（即情感共享），积极情绪具有传染性（例如，一个快乐的人的存在会提升他人的幸福感），共情能力可能是提高个人主观幸福感水平的关键因素。基于先前的研究表明，血清素2A受体基因中的单核苷酸多态性[rs6311鸟嘌呤（G）与腺嘌呤（A）]与对情绪刺激的敏感性以及几种精神障碍（如抑郁症）有关，我们预测这种多态性可能与分享幸福的效果有关。为了阐明分享幸福效果的神经和遗传相关性，我们首先在“快乐情绪”诱发任务（情感事件想象任务）期间进行了功能磁共振成像（fMRI），在此期间我们操纵了想象事件的效价（积极、中性或消极），以及一个经历积极效价事件的朋友的存在与否。我们招募了年轻成年女性参与这项fMRI研究，因为女性的共情能力可能高于男性。无论事件效价如何，在有朋友在场的情况下，参与者感觉更快乐（<0.01），并且跨越内侧前额叶皮质、颞顶联合区、颞极和楔前叶的心理化/心理理论网络显著更活跃（<0.05）。此外，与AA基因型的参与者相比，具有GG（<0.01）和AG（<0.05）基因型的参与者在对幸福的共情（中性/有朋友在场条件）期间感受更快乐，并且心理化/心理理论网络的一部分也有更大的激活（<0.05）。在一项基于相对大样本的基于 vignette 的问卷调查的后续研究中，向男性和女性参与者呈现相同的想象事件，其中操纵了事件的效价和朋友的存在与否。结果表明，无论性别如何，在与幸福相关的共情方面存在基因差异（<0.05）。研究结果表明，多态性通过调节心理化/心理理论网络的活动与分享幸福的效果相关。
