Son Shuraku, Kubota Manabu, Miyata Jun, Fukuyama Hidenao, Aso Toshihiko, Urayama Shin-ichi, Murai Toshiya, Takahashi Hidehiko
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto 606-8507, Japan.
Human Brain Research Center, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaharacho, Sakyo-ku, Kyoto 606-8507, Japan.
Schizophr Res. 2015 May;164(1-3):221-6. doi: 10.1016/j.schres.2015.03.009. Epub 2015 Mar 29.
Both creativity and schizotypy are suggested to be manifestations of the hyperactivation of unusual or remote concepts/words. However, the results of studies on creativity in schizophrenia are diverse, possibly due to the multifaceted aspects of creativity and difficulties of differentiating adaptive creativity from pathological schizotypy/positive symptoms. To date, there have been no detailed studies comprehensively investigating creativity, positive symptoms including delusions, and their neural bases in schizophrenia. In this study, we investigated 43 schizophrenia and 36 healthy participants using diffusion tensor imaging. We used idea, design, and verbal (semantic and phonological) fluency tests as creativity scores and Peters Delusions Inventory as delusion scores. Subsequently, we investigated group differences in every psychological score, correlations between fluency and delusions, and relationships between these scores and white matter integrity using tract-based spatial statistics (TBSS). In schizophrenia, idea and verbal fluency were significantly lower in general, and delusion score was higher than in healthy controls, whereas there were no group differences in design fluency. We also found positive correlation between phonological fluency and delusions in schizophrenia. By correlation analyses using TBSS, we found that the anterior part of corpus callosum was the substantially overlapped area, negatively correlated with both phonological fluency and delusion severity. Our results suggest that the anterior interhemispheric dysconnectivity might be associated with executive dysfunction, and disinhibited automatic spreading activation in the semantic network was manifested as uncontrollable phonological fluency or delusions. This dysconnectivity could be one possible neural basis that differentiates pathological positive symptoms from adaptive creativity.
创造力和精神分裂症样特质都被认为是异常或遥远概念/词汇过度激活的表现。然而，关于精神分裂症患者创造力的研究结果各不相同，这可能是由于创造力的多面性以及区分适应性创造力与病理性精神分裂症样特质/阳性症状存在困难。迄今为止，尚未有详细研究全面调查精神分裂症患者的创造力、包括妄想在内的阳性症状及其神经基础。在本研究中，我们使用扩散张量成像对43名精神分裂症患者和36名健康参与者进行了调查。我们使用观念、设计和言语（语义和语音）流畅性测试作为创造力得分，使用彼得斯妄想量表作为妄想得分。随后，我们使用基于纤维束的空间统计学（TBSS）研究了各项心理得分的组间差异、流畅性与妄想之间的相关性，以及这些得分与白质完整性之间的关系。在精神分裂症患者中，总体而言观念和言语流畅性显著较低，妄想得分高于健康对照组，而设计流畅性方面没有组间差异。我们还发现精神分裂症患者的语音流畅性与妄想之间存在正相关。通过使用TBSS的相关性分析，我们发现胼胝体前部是显著重叠的区域，与语音流畅性和妄想严重程度均呈负相关。我们的结果表明，半球间前部连接障碍可能与执行功能障碍有关，语义网络中不受抑制的自动扩散激活表现为无法控制的语音流畅性或妄想。这种连接障碍可能是区分病理性阳性症状与适应性创造力的一种可能的神经基础。
