Dudina Anastasiia N, Tomyshev Alexander S, Ilina Ekaterina V, Romanov Dmitriy V, Lebedeva Irina S
Mental Health Research Center, 34 Kashirskoye Sh, Moscow 115522, Russian Federation.
Mental Health Research Center, 34 Kashirskoye Sh, Moscow 115522, Russian Federation.
Prog Neuropsychopharmacol Biol Psychiatry. 2025 Jan 10;136:111185. doi: 10.1016/j.pnpbp.2024.111185. Epub 2024 Oct 30.
Despite the high clinical role of delusions as a transnosological psychopathological phenomenon, the number of experimental studies on the different types of delusions across schizophrenia spectrum is still relatively small, and their results are somehow inconsistent. We aimed to understand the current state of knowledge regarding the structural and functional brain alterations in delusions to determine whether particular types of delusions are associated with specific brain changes and to identify common alterations underlying the formation and persistence of delusions regardless of their content.
For this systematic review, we followed PRISMA guidelines to search in PubMed for English papers published between 1953 and September 30, 2023. The initial inclusion criteria for screening purposes were articles that investigated delusions or subclinical delusional beliefs in schizophrenia spectrum disorders, high clinical or genetic risk for schizophrenia using fMRI, sMRI or/and dwMRI methods. Exclusion criteria during the screening phase were articles that investigated lesion-induced or substance-induced delusions, delusions in Alzheimer's disease and other neurocognitive disorders, single case studies and non-human studies. The publication metadata were uploaded to the web-tool for working on systematic reviews, Rayyan. For each of the studies, a table was filled out with detailed information.
We found 1752 records, of which 95 full-text documents were reviewed and included in the current paper. Both nonspecific and particular types of delusions were associated with widespread structural and functional alterations. The most prominent areas affected across all types of delusions were the superior temporal cortex (predominantly left language processing areas), anterior cingulate/medial prefrontal cortex and insula. The most reproducible findings in paranoia may be alterations in the functioning of the amygdala and its interactions with other regions. Somatic delusions and delusional infestation were mostly characterized by alterations in the insula and thalamus.
The data are ambiguous; however, in general the predictive processing framework seems to be the most widely accepted approach to explaining different types of delusions. Aberrant prediction errors signaling during processing of social, self-generated and sensory information may lead to inaccuracies in assessing the intentions of others, self-relevancy of ambiguous stimuli, misattribution of self-generated actions and unusual sensations, which could provoke delusional ideation with persecutory, reference, control and somatic content correspondingly. However, currently available data are still insufficient to draw conclusions about the specific biological mechanisms of predictive coding account of delusions. Thus, further studies exploring more homogeneous groups and interaction of diagnoses by types of delusions are needed. There are also some limitations in this review. Studies that investigate delusions induced by lesions, substance abuse or neurodegeneration and studies using modalities other than fMRI, sMRI or dwMRI were not included in the review. Due to the relatively small number of publications, we systematized them based on a certain type of delusions, while the results could also be affected by the diagnosis of patients, the presence and type of therapy, illness duration etc.
尽管妄想作为一种跨疾病的精神病理现象具有很高的临床意义，但针对精神分裂症谱系中不同类型妄想的实验研究数量仍然相对较少，且结果存在一定的不一致性。我们旨在了解目前关于妄想中大脑结构和功能改变的知识现状，以确定特定类型的妄想是否与特定的大脑变化相关，并识别出无论妄想内容如何，其形成和持续存在背后的共同改变。
对于本系统评价，我们遵循PRISMA指南，在PubMed中搜索1953年至2023年9月30日期间发表的英文论文。筛选的初始纳入标准是使用功能磁共振成像（fMRI）、结构磁共振成像（sMRI）或/和扩散加权磁共振成像（dwMRI）方法研究精神分裂症谱系障碍中的妄想或亚临床妄想信念、精神分裂症的高临床或遗传风险的文章。筛选阶段的排除标准是研究病变诱发或物质诱发的妄想、阿尔茨海默病和其他神经认知障碍中的妄想、单病例研究和非人类研究的文章。将发表的元数据上传到用于系统评价的网络工具Rayyan。为每项研究填写了包含详细信息的表格。
我们找到了1752条记录，其中95篇全文文献经过评审并纳入了本文。非特异性和特定类型的妄想均与广泛的结构和功能改变相关。在所有类型的妄想中受影响最显著的区域是颞上叶皮质（主要是左侧语言处理区域）、前扣带回/内侧前额叶皮质和脑岛。在偏执妄想中最可重复的发现可能是杏仁核功能及其与其他区域相互作用的改变。躯体妄想和被感染妄想主要以脑岛和丘脑的改变为特征。
数据尚不明确；然而，总体而言，预测加工框架似乎是解释不同类型妄想最被广泛接受的方法。在处理社会、自我产生和感觉信息期间异常的预测误差信号可能导致在评估他人意图、模糊刺激的自我相关性、自我产生行为的错误归因和异常感觉方面出现不准确，这可能相应地引发带有迫害、牵连、控制和躯体内容的妄想观念。然而，目前可用的数据仍不足以就妄想的预测编码解释的具体生物学机制得出结论。因此，需要进一步研究探索更同质的群体以及按妄想类型进行诊断的相互作用。本评价也存在一些局限性。研究病变、药物滥用或神经退行性变诱发的妄想的研究以及使用fMRI、sMRI或dwMRI以外方式的研究未纳入本评价。由于出版物数量相对较少，我们根据某种类型的妄想对它们进行了系统化整理，而结果也可能受到患者诊断、治疗的存在和类型、病程等因素的影响。
