An Investigation Of The Functional Connectivity Patterns Of Insula Subparts And Related Factors In Young Males After Sleep Deprivation

Research background and purpose:The insula is a key hub for higher-ordered cognitive functions.Sleep deprivation(SD)induces aberrant insular functional connectivity(FC).The insula comprises at least 3 functionally distinct subregions-anterior dorsal(dAI),anterior ventral(vAI)and posterior insula(PI).Previous studies have only assessed impact of SD on anterior insular FC,leaving the FC of PI unknown.It is also unclear whether bilateral insular subregions are equally affected.This study aims to examine the FC across 3 insular subregions in young males after 36-hour SD.Materials and Methods:A total of 54 healthy young men completed 36-hour SD.Two sessions of psychomotor vigilance task(PVT),Epworth Sleepiness Scale(ESS),Profile of Mood States(POMS)and 3T resting-state functional magnetic resonance imaging(rs-fMRI)scans were arranged.Results:1.After 36-hour sleep deprivation,the anterior insula showed enhanced connectivity with the cerebellum,middle frontal gyrus,putamen,and postcentral gyrus,while showing decreased connectivity with the temporal lobes,angular gyrus,Calcarine sulcus,anterior cingulum,and medial orbitofrontal gyrus.The posterior insula had increased connectivity with the middle frontal gyrus,inferior temporal gyrus,and inferior parietal gyrus,but showed an anti correlation with the middle temporal regions,posterior cingulum,and angular gyrus.2.The paired-t test revealed a statistically different PVT performance after 36 hours of sleep deprivation:a greater number of lapses and false starts was reported.Mean response time,median response time and standard deviation response time were larger.There was also an increase in maximum response time,minimum response time,fastest and slowest 10%response time.3.After 36-hour sleep deprivation,there was a statistically increase scores in Epworth Sleepiness Scale.4.After 36-hour sleep deprivation,there was a statistically increase in total scores in total mood disturbance,tension,anger,fatigue,depression and confusion;but a decrease in vigor and self-esteem.5.The correlation analysis indicated weak correlations between changes in functional connectivity,scales and PVT performance,but Bonferroni multiple comparisons correction reported all P>0.05.Conclusion:1.After 36-hour sleep deprivation,the whole brain functional connectivity of insula subregions displayed aberrant patterns.2.A worse sustained attention after 36-hour sleep deprivation was observed.3.There was an increase in subjective sleepiness after 36-hour sleep deprivation.4.There was a more negative mood after 36-hour sleep deprivation.5.There were weak correlations between altered functional connectivity,changes in rating scale scores and PVT performance,but they did not survive Bonferroni multiple comparisons correction.Future studies should improve trial designs to further explain/verify the our results.