Department of General Psychology, University of Padova, Italy.
Department of General Psychology, University of Padova, Italy; Padova Neuroscience Center, University of Padova, Italy.
Neuroimage Clin. 2022;36:103241. doi: 10.1016/j.nicl.2022.103241. Epub 2022 Oct 19.
Past voxel-based morphometry (VBM) studies demonstrate reduced grey matter volume (GMV) in schizophrenia (SZ) patients' brains in various cortical and subcortical regions. Probably due to SZ symptoms' heterogeneity, these results are often inconsistent and difficult to integrate. We hypothesized that focusing on auditory verbal hallucinations (AVH) - one of the most common SZ symptoms - would allow reducing heterogeneity and discovering further compelling evidence of SZ neural correlates. We carried out two voxel-based meta-analyses of past studies that investigated the structural correlates of AVH in SZ. The review of whole-brain VBM studies published until June 2022 in PubMed and PsychInfo databases yielded (a) 13 studies on correlations between GMV and AVH severity in SZ patients (n = 472; 86 foci), and (b) 11 studies involving comparisons between hallucinating SZ patients (n = 504) and healthy controls (n = 524; 74 foci). Data were analyzed using the Activation Likelihood Estimation method. AVH severity was associated with decreased GMV in patients' left superior temporal gyrus (STG) and left posterior insula. Compared with healthy controls, hallucinating SZ patients showed reduced GMV on the left anterior insula and left inferior frontal gyrus (IFG). Our findings revealed important structural dysfunctions in a left lateralized cluster of brain regions, including the insula and temporo-frontal regions, that significantly contribute to the severity and persistence of AVH. Structural atrophy found in circuits involved in generating and perceiving speech, as well as in auditory signal processing, might reasonably be considered a biological marker of AVH in SZ.
过去的基于体素的形态测量学（VBM）研究表明，精神分裂症（SZ）患者大脑的灰质体积（GMV）在各种皮质和皮质下区域减少。可能由于 SZ 症状的异质性，这些结果往往不一致且难以整合。我们假设专注于听觉言语幻觉（AVH） - SZ 的最常见症状之一 - 将有助于减少异质性并发现更多有力的 SZ 神经相关性证据。我们对过去研究进行了两项基于体素的荟萃分析，这些研究调查了 SZ 中 AVH 的结构相关性。对截至 2022 年 6 月在 PubMed 和 PsychInfo 数据库中发表的全脑 VBM 研究进行综述，得出了以下结果：（a）13 项研究探讨了 SZ 患者 AVH 严重程度与 GMV 之间的相关性（n = 472；86 个焦点）；（b）11 项研究涉及比较有幻觉的 SZ 患者（n = 504）和健康对照组（n = 524；74 个焦点）。使用激活似然估计方法进行数据分析。AVH 严重程度与患者左颞上回（STG）和左后岛叶的 GMV 减少有关。与健康对照组相比，有幻觉的 SZ 患者的左前岛叶和左额下回（IFG）的 GMV 减少。我们的研究结果揭示了大脑左侧区域一个重要的结构功能障碍集群，包括岛叶和颞额区域，这些区域对 AVH 的严重程度和持续时间有重要贡献。在产生和感知言语以及听觉信号处理中涉及的回路中发现的结构萎缩，合理地被认为是 SZ 中 AVH 的生物学标志物。
