Functional Connectivity And Activity Flow In Dorsolateral Prefrontal Region In Schizophrenia Patients

Schizophrenia has an extremely serious negative impact on society and a huge burden on patients and their families.However,there is no unified and effective treatment for schizophrenia in clinical treatment.A number of factors contribute to treatment difficulties,perhaps the most critical of which is the symptom diversity of schizophrenia,involving multiple affective,cognitive,and motor aspects.Schizophrenia has brain dysfunction,particularly in frontal regions involved in coordinating brain signals.Based on the sensory gating hypothesis,we propose that abnormal visual processing can cause brain activity in attentional regions,but this phenomenon has not been found in previous studies.Alternatively,the dorsolateral prefrontal(DLPFC)has been shown to be associated with attention shifting.Therefore,this study focused on the functional connectivity and laterality of DLPFC in patients with schizophrenia.In addition,the distributed information flow of abnormal activation was studied by combining the method of activity flow mapping with the visual stimulation task.At the same time,whether the DLPFC is involved in visual processing in schizophrenia was explored.Firstly,the DLPFC was divided into four subregions,and the functional connectivity between subregions and whole brain voxels was calculated.Laterality indices of functional connectivity were then calculated separately for different subregions.The results showed that the DLPFC functional connectivity was significantly decreased in schizophrenia compared with healthy controls.Specifically,the main differences were distributed in the putamen,inferior frontal gyrus and superior cerebellar peduncle.In the laterality analysis,we found that schizophrenia patients showed significantly decreased laterality in most regions of the DLPFC,including caudate nucleus,middle frontal gyrus,insula,and precentral gyrus,compared with healthy controls.However,schizophrenia patients showed increased laterality in functional connectivity with the left putamen.These results suggest that the DLPFC plays an important role in schizophrenia and there is asymmetry in functional connectivity.Moreover,the laterality differences within the striatum suggest that there may be functional compensation.Secondly,the distribution of dysfunction in schizophrenia and whether there is abnormal sensory gating during visual processing were explored in combination with visual tasks.Firstly,the task-state data were used for activation analysis using the general linear model,and then the results of repeated measures ANOVA and DLPFC were used as the region of interest to calculate the activity flow map.Finally,the activity flow map was used to predict the actual activation.The results showed that the activation differences between the two groups were mainly concentrated in the visual cortex and hippocampus.After the construction of the abnormal region activity flow map,it was found that the contributions of different regions to the abnormal brain areas were not the same,and the contributions of attention network and frontoparietal network in the visual activation area of schizophrenia patients were significantly reduced.Predicted activation reproduces group differences in regions of difference,suggesting that distributed activity flow is an important part of constructing regional activation.Finally,the DLPFC was found to be involved to some extent in the processing of basal visual stimuli in schizophrenia but not in healthy subjects.These findings may confirm the rationality of sensory gating hypothesis to a certain extent.After basic vision,patients with schizophrenia cannot filter useless information reasonably through gating and activate higher networks such as attention network,resulting in visual processing disorders.In addition,due to the abnormality of sensory gating,patients with schizophrenia receive too much redundant information,resulting in slow information processing and cognitive impairment.It shows that using the activity flow mapping model to study the pathophysiology of schizophrenia is valuable and provides new methods and directions for future research.In conclusion,the present study explored the important role of DLPFC in schizophrenia patients by combining resting state and task state.The results showed that there was suprathreshold disconnection in the DLPFC and subthreshold activity was involved in visual information processing in schizophrenia.It is hoped that this study can enhance the understanding of DLPFC in patients with schizophrenia and provide new ideas for studying the pathophysiology of schizophrenia in the future.