Correlation Between Cognitive Impairment And Brain Structure And Function In Patients With Early-onset Schizophrenia

Background and objective: Early-onset schizophrenia（EOS）refers to schizophrenia with onset before the age of 18.Its prevalence is low,but its onset is insidious,with severe symptoms and poor prognosis.EOS seriously affect the physical and mental development of adolescent patients,resulting in a more severe disease burden.As a core feature of schizophrenia,cognitive impairment is more severe in patients with EOS than in adults with schizophrenia.Previous studies have shown that both brain structure and function in EOS patients are affected by the disease.At present,there are few neuroimaging studies exploring the cognitive impairment of EOS from the perspective of brain structure and function,and the underlying neuropathological mechanism of cognitive impairment in EOS patients is still unclear.Therefore,this study intends to explore the correlation between cognitive impairment and brain regions in EOS patients from the perspective of brain structure and function,and to provide potential neural targets for the treatment and intervention of patients with early-onset schizophrenia in the future.Methods: 43 adolescent patients aged 13-18 years who met the ICD-10 diagnostic criteria for schizophrenia were collected,and 18 healthy adolescent volunteers were recruited through posters.Two psychiatric graduate students who have undergone consistent training completed the collection of general data of the two groups of subjects,used the Stroop color word test to evaluate the subjects’ executive function,used the Theory of Mind Picture-Sequencing Task to evaluate the subjects’ theory of mind ability,and completed structural and resting-state functional image scans of the subjects.The brain structure and function of the subjects were evaluated by gray matter volume（GMV）and amplitude of low-frequency fluctuation（ALFF）analysis methods,respectively.Two-sample t-test was used to compare the differences in cognitive function levels between EOS patients and healthy controls,and correlation analysis was used to evaluate the correlation between cognitive function indicators and brain imaging indicators in the two groups,respectively.Results:（1）Compared with the healthy control group,Stroop-point（t =3.843,P <0.001）,Stroop-word（t =2.885,P =0.005）and Stroop-color word（t =3.888,P < 0.001）in the EOS group were higher,and the difference was statistically significant（P < 0.05）;primary belief（t =-2.988,P =0.005）,primary false belief（t =-4.521,P < 0.001）,secondary false belief（t =-2.025,P =0.047）,reciprocity（t =-2.834,P =0.006）,deception（t =-2.443,P =0.018）,detection of deception（t =-2.892,P =0.006）and total scores（t =-5.113,P <0.001）were lower,and the difference was statistically significant（P <0.05）.There were no significant differences between two groups in the scores of secondary belief（t =-0.644,P =0.522）,three-level false beliefs（t =-1.836,P =0.071）,and sense of reality（t =462,P =0.646）（P >0.05）.（2）In the GMV analysis,after controlling the covariates such as age,gender,years of education,and total intracranial volume（TIV）,the study found that the Stroop-word in the EOS group was positively correlated with the GMV of the right middle frontal gyrus（cluster-level FWE correction,adjusted P < 0.05,partial correlation coefficient pr = 0.629,P <0.001）.There were no correlations between other cognitive function indicators and GMV in EOS patients（not corrected for cluster-level FWE）.In the partial correlation analysis based on region of interest（ROI）,there was no significant correlation between Stroop-word and the GMV of the right middle frontal gyrus in healthy controls（pr =-0.324,P =0.258）.（3）In the ALFF analysis,controlling for age,gender,years of education,and frame-wise displacement（FD）as covariates,the study found that the TOM-sense of reality in the EOS group was negatively correlated with the ALFF of the left hippocampus（cluster-level FWE correction,adjusted P < 0.05,pr =-0.647,P <0.001）and the left precentral gyrus（cluster-level FWE correction,adjusted P < 0.05,pr=-0.724,P <0.001）.There were no correlations between other cognitive function indicators and ALFF in the EOS patients（not corrected for cluster-level FWE）.And the ROI-based partial correlation analysis found that the TOM-sense of reality in the healthy controls was not significantly correlated with the ALFF in the left hippocampus（pr =-0.071,P =0.810）and left precentral gyrus（pr =-0.232,P =0.425）.Conclusion: Compared with normal peers,EOS patients have the impaired executive function and theory of mind ability.The impaired executive function is associated with increased gray matter volume of the right middle frontal gyrus,and the impaired theory of mind ability is associated with functional abnormalities in the left hippocampus and left precentral gyrus,revealing the possible neural mechanism of cognitive impairment in EOS patients.