A Resting State FMRI Study On Adolescent Suicide Attempt

PART ONE: A RESTING STATE fMRI STUDY ONADOLESCENT SUICIDE ATTEMPT WITH DEPRESSIVEDISORSER BASED ON ALFF NANLYSISObject: Using ALFF analysis method to compare the brain functionalactivity in resting-state between adolescent depressive patients with andwithout suicide attempts and healthy controls. To investigate therelationship between the abnormalities of local brain functional activity inresting-state and suicide attempt with depressive disorder in adolescence.To explore the potential mechanism of adolescent suicide attempt withdepressive disorder by comparing local synchronization of resting-statefMRI signals.Methods:35adolescent depressive patients with suicide attempt(ATT),18patients without suicide attempt (NAT) and47gender, age andeducation matched healthy controls (HC) performed clinical psychologicalassessment and participated in resting-state functional magnetic resonance(R-fMRI) scan. We compared the differences in the fractional amplitude of low-frequency fiuctuation (ALFF) among the three groups and investigatedthe correlation between clinical measurements and ALFF in the regionsdisplaying significant group differences.Results:1. There was no difference in gender (P=0.602), age(P=0.584) and education (P=0.289) among the three groups, while the threegroups had significant difference in QSA and BIS-11scale. ATT group hadsignificantly higher QSA and BIS-11scores than HC group (P<0.001), aswell as QSA and BIS-11scores were higher in NAT group than HC group.However, there was no difference in HAMD (P=0.082), BDI (P=0.263),BHS (P=0.125) and SSI (P=0.906) scale between ATT group andNATgroup.2. Both the ATT and NAT groups showed an increased ALFF in the leftmiddle occipital gyrus (l-MOG), right middle temporal gyrus (r-MTG) anda decreased ALFF in the right caudate nucleus (r-Cau) compared to theHCgroup. The ATT group demonstrated an increased ALFF in left middlefrontal gyrus (l-MFG), right superior temporal gyrus (r-STG) and the leftmiddle temporal gyrus (l-MTG) relative to NAT and HC groups.3.The ALFF values of right temporal (r-MTG) and left middle temporalgyrus (l-MTG) were positively associated with BIS-11scores(r=0.648,P=0.004; r=0.481, P=0.044) in ATT group; and there were negativecorrelations between ALFF value of left inferior temporal gyrus (l-ITG)and HAMD（r=-0.448，P=0.007）、BDI（r=-0.453，P=0.006） and BHS （r=-0.388，P=0.021） scale in NAT group.Conclusion: Preliminary findings suggest that abnormal ALFF valuesof the left middle frontal gyrus (l-MFG), right superior temporalgyrus(r-STG), left middle temporal gyrus (l-MTG) and right caudatenucleus (r-Cau) may be related to the underling diathesis for suicideattempt. At the same time, the left middle frontal gyrus (l-MFG), leftsuperior temporal gyrus (l-ITG), right supplementary motor area (SMA),left middle middle occipital gyrus (l-MOG) may be involved in thepathophysiological mechanism of depression, and may be relevant tothe neurobiological basis of depression. PART TWO: A RESTING STATE fMRI STUDY ONADOLESCENT SUICIDE ATTEMPT WITHOUTDIAGNOSABLE PSYCHIATRIC DISORDER BASED ONREGIONAL HOMOGENEITY ANALYSISObject: To investigate the brain functional mechanism and neurobiologicalbasis of suicide through the local functional activity analysis method of resting state fMRI.①To explore the difference of local functional activitybetween suicidal adolescence without psychiatric diagnosis (SA group) andhealthy controls (HC group) by using regional homogeneity (ReHo)analysis.②To explore the relationship between the abnormality of localfunctional activity in SA group and clinical characteristics.③To reveal thebrain function network mechanisms of adolescent suicidal behavior.Methods:19suicidal adolescences without psychiatric diagnosis (SAgroup) and20age, sex and educational level matched healthy controls (HCgroup) performed R-fMRI examine and clinical psychological assessmentscale.Using regional homogeneity analysis method to compare the localsynchronization of R-fMRI signals in SA group and HC group. Once again,extract the ReHo value from the group compared significant differences’brain areas and performed correlation analysis with the clinical scale.Results:1. There was no significant difference in age, gender, educationlevel, HAMA, HAMD, QSA scale between the SA group and HC group,but the SA group had significantly higher total Barratt Impulsiveness Scale(BIS-11) scores (P<0.01).2. Compared to HC group, the SA group exhibited significantly lower meanReHo in the left (L) fusiform (BA30) and supraorbital inferior frontal gyri(BA47), L hippocampus (BA35), bilateral parahippocampal (BA37) andmiddle frontal gyri (BA46), right (R) angular gyrus (BA7), and cerebellumposterior lobe (VIII and VI, BA18). Conversely, SA group ReHo was higher in the R supraorbital middle prefrontal gyrus (BA11), R inferiorparietal lobe (BA40), and L precuneus (BA7).3. No significant correlations were found between the ReHo values in anyROI and subject gender, age, years of education, suicide method, BIS totalscore, or SAQ total score.Conclusion: The brain regions in frontal-parietal-cerebellar network,frontal-parietal network，frontal-limbic network and default mode networkare involved in the pathophysiological process,and the Local functionalconnectivity is altered in multiple regions of cerebral cortex, limbic system,and cerebellum of suicidal adolescents. It suggests that there may bespecific neural network underlying suicidal behavior.