Movement Control and Neuroplasticity Research Group, KU Leuven, Belgium; IRCCS San Camillo Hospital, Venice, Italy.
Department of General Psychology, University of Padova, Italy; Padova Neuroscience Center, University of Padova, Italy.
J Psychiatr Res. 2022 Nov;155:24-32. doi: 10.1016/j.jpsychires.2022.08.006. Epub 2022 Aug 9.
Although alterations of the default mode network (DMN) in schizophrenia (SZ) have been largely investigated, less research has been carried out on DMN alterations in different sub-phenotypes of this disorder. The aim of this pilot study was to compare DMN features among SZ patients with and without auditory verbal hallucinations (AVH). Three groups of 17 participants each were considered: patients with hallucinations (AVH-SZ), patients without hallucinations (nAVH-SZ) and age-matched healthy controls (HC). The DMN spatial pattern was similar between the nAVH-SZ and HC, but the comparison between these two groups and the AVH-SZ group revealed alterations in the left Angular Gyrus (lAG) node of the DMN. Using a novel approach based on normalized fractional Amplitude of Low-Frequency Fluctuations (fALFF), the AVH-SZ subgroup showed altered spectral activity in the DMN compared with the other two groups, especially in the lower-frequency bands (0.017-0.04 Hz). Significant positive correlations were found for both SZ groups collapsed, and for the nAVH-SZ group alone between delusional scores (PANSS-P1) and slow fALFF bands of the DMN. Narrowing the analysis to the ROI centered on the lAG, significant correlations were found in the AVH-SZ group for hallucination scores (PANSS-P3) and Slow-5 and Slow-4 (both positive), and Slow-3 (negative) fALFF bands. Our results reveal the central role of the lAG in relation to hallucinations, an important cortical area connecting auditory cortex with several hubs (including frontal linguistic centers) and involved in auditory process monitoring.
尽管精神分裂症（SZ）的默认模式网络（DMN）改变已经得到了广泛研究，但对该障碍不同亚表型的 DMN 改变的研究较少。本初步研究旨在比较有和无听觉言语幻觉（AVH）的 SZ 患者的 DMN 特征。考虑了三组每组 17 名参与者：有幻觉的患者（AVH-SZ）、无幻觉的患者（nAVH-SZ）和年龄匹配的健康对照者（HC）。nAVH-SZ 和 HC 之间的 DMN 空间模式相似，但与这两组相比，nAVH-SZ 和 AVH-SZ 之间的比较显示 DMN 中的左角回（lAG）节点发生了改变。使用基于归一化低频波动分数振幅（fALFF）的新方法，AVH-SZ 亚组与其他两组相比，DMN 中的频谱活动发生了改变，特别是在较低的频率带（0.017-0.04 Hz）。对于两个 SZ 组的合并组和 nAVH-SZ 组单独使用，均发现了妄想分数（PANSS-P1）和 DMN 的慢 fALFF 带之间的显著正相关。将分析范围缩小到以 lAG 为中心的 ROI，在 AVH-SZ 组中，幻觉分数（PANSS-P3）和慢 fALFF 带 Slow-5 和 Slow-4（均为阳性）与 Slow-3（阴性）之间存在显著相关性。我们的结果揭示了 lAG 在与幻觉相关的重要作用，这是一个连接听觉皮层与几个中枢（包括额叶语言中枢）的重要皮质区域，并参与听觉过程监测。
