Schizophrenia with a positive family history is called familial-schizophrenia (PFS), which is considered to be more caused by genetic factors, while schizophrenia with a negative family history is called sporadic-schizophrenia (PSS), which is considered to be more caused by environmental factors. Previous studies have shown that there are some differences in clinical symptoms between familial schizophrenia and sporadic schizophrenia [1, 2]; In addition, structural magnetic resonance imaging studies show that the density of thalamic gray matter in patients with familial schizophrenia is lower than that in healthy controls and sporadic schizophrenia [3]. However, are there any differences between the two types of schizophrenia in terms of brain functional network? On the basis of reference [4], this paper studies the brain functional network and topological structure of patients with familial schizophrenia and sporadic schizophrenia by resting magnetic vibration technology, in order to reveal the difference of brain function between them. The author here analyzes the analysis methods and results of this paper, hoping to inspire all friends and help your research.
research method
26 patients with PSS, 26 patients with PFS and 26 controls were collected in the hospital, and resting fMRI was collected.
The fMRI data of subjects were preprocessed by SPM8 software, and the functional connection matrix between 90 ROI brain regions was constructed by GRETNA software. Specifically, Pearson correlation coefficient between 90 AAL brain region BOLD signals is calculated, and a Pearson correlation coefficient matrix of 90*90 is obtained for each object.
For the obtained functional connection matrix, the researcher calculated the following topological parameters of each functional connection matrix by using the analysis method of graph theory: network clustering coefficient Cp, characteristic path length Lp, normalized clustering coefficient γ, normalized characteristic path length λ, small world δ coefficient δ, global efficiency Eglob and local efficiency Eloc.
Finally, the researcher uses the analysis method of network-based statistics (NBS) to study the sub-networks with significant differences between different test groups.
research results
Compared with healthy people, the standardized aggregation coefficient γ, small-world coefficient δ and local efficiency Eloc of familial schizophrenia patients were significantly decreased. . Compared with PSS patients, the Eloc of PFS patients is also significantly lower, and the specific results are shown in figure 1.
Compared with HC, PFS showed significantly increased nodal centrality in the following brain regions: right middle cingulate gyrus (MCC) and middle occipital gyrus (Mog); However, in the following brain regions: bilateral middle frontal gyrus (MFG), left insula (INS), hippocampus (Cal), caudate nucleus (Cauda), putamen (Put), hippocampus (Hg) and right thalamus (T), as shown in Figure 2.
Compared with healthy subjects, PSS showed significantly increased nodal connections in the following brain regions: bilateral supplementary motor area (SMA), middle part of superior frontal gyrus (SFGM), left parahippocampal gyrus (pH), right cuneiform lobe (Cun) and MOG；; However, in the following brain regions: left olfactory cortex (OLF), ins, cal, right mfg, central accessory lobe (PCL) and Put, as shown in Figure 3.
Compared with PSS patients, PFS patients showed significantly increased node centrality in the following brain regions: right upper parity gyrus (SPL), superior marginal gyrus (SMG) and PCL；; However, in the following brain regions: left cau, left hg, right orbital part (IFG circle) infected with frontal gyrus, SMA and th. See Figure 4 for details.
The researchers used the method of the National Bureau of Statistics. Compared with HC, PFS patients show a subnet with significantly lower functional connectivity, as shown in Figure 5A. However, PSS patients showed subnetworks with significantly reduced functional connection strength, as shown in fig. 5B.
Finally, the researcher analyzed the correlation between the calculated brain functional network index and the clinical data score PANSS, and the results are shown in Figure 6. The results showed that the normalized clustering coefficient γ and small-world coefficient δ of PFS patients were negatively correlated with PANSS negative scores. For PSS patients, PCL node efficiency. R brain region is negatively correlated with PANSS negative score, while the node centrality of Cal is negatively correlated with PANSS negative score. L brain region is significantly correlated with PANSS positive score.
abstract
In this paper, the functional relationship of resting fMRI is combined with graph theory to reveal the differences of brain functional networks between two types of schizophrenia (PSS and PFS). The results showed that compared with PSS patients, PFS patients showed significantly reduced local efficiency (Eloc) and significantly increased node centrality in the following brain regions: right superior parietal gyrus (SPL), superior marginal gyrus (SMG) and PCL, but in the following brain regions: left cau, left hg, right orbital region of infected frontal gyrus (IFG _ ORB), SMA and th, the node centrality was significantly reduced. Combined with previous studies, these results show that PFS and PSS are different not only in clinical manifestations and brain structure, but also in functional networks, which may be mainly caused by different factors.