Effects Of Sleep Deprivation On Learning And Memory In Healthy Adults: A Functional Magnetic Resonance Imaging Study

Objective To investigate:(1)the changes of sleep deprivation(SD)with different times on human brain regional homogeneity(Re Ho);(2)the effect of SD to the learning and memory network and the neural mechanism of learning and memory network disturbance induced by 36 hours sleep deprivation(SD).Methods Forty six healthy volunteers were recruited in this experiment with self controlled design and divided into two groups.(1)28 healthy individuals participated in this study.Resting-state f MRI scans were collected under rest wakefulness,24 and 36 hours SD.The Re Ho approach was employed to analyze the imaging data,and SPM 8 was used to perform one-way ANOVA,with a p value < 0.001(corrected FDR)and cluster size(k value)> 20 voxels considerate statistic significant.(2)18 young male healthy volunteers were enrolled in this study.Resting state functional magnetic imaging(rs-f MRI)data was collected by blood oxygen level dependence functional magnetic imaging(BOLD-f MRI)during rest wakefulness(RW)and 36 hours SD.Bilateral hippocampus were selected as seed points by REST software ALL template.And then compared the differences of functional connectivity(FC)between bilateral hippocampus and whole brain regions by using paired-t test withinstatistical parametric mapping 8(SPM8)software.Finally,correlation analysis had been done between significant FC of brain regions and WMS MQ values(SD-RW).Results(1)Compared with rest wakefulness,mainly SD induced enhanced brain Re Ho in the right Fusiform?the frontal?Temporal Lobe and the left Thalamus;decreased Re Ho in the right Precuneus?Supramarginal and the left Frontal Middle lobe?Postcentral.With SD times went on,enhanced brain Re Ho were found in Precuneus?Angular and Frontal Sup Medial;and decreased Re Ho were found in the Precentral Gyrus?Temporal Lobe and Medial Frontal Gyrus.(2)Compared with RW,the bilateral hippocampus showed positive connected with the right dorsal posterior cingulate cortex,and showed negative functional connectivity with bilateral postcentral gyrus.The WMS MQ was significantly decreased after 36 hours SD.The connection between bilateral hippocampus and the right posterior cingulate cortex showed negative correlation with the deduction of WMS MQ(left: r =-0.463,P = 0.015;right: r =-0.546,P = 0.003).Conclusion(1)SD caused abnormal changes in whole brain network changes by connection of multiple brain regions,especially the brain regions which are mainly in the Frontal lobe?Temporal Lobe and Thalamus.And the SD times can reflect the changes of Re Ho in functional regions.(2)36 hours SD can reduce the ability of learning and memory.And SD has a significant effect on bilateral hippocampal FC.The FC between bilateral hippocampus and right dorsal posterior cingulate cortex is significant increased while that between bilateral postcentral gyrus is decreased after 36 hours SD.These findings may be the essential neural mechanism of learning and memory by 36 hours SD.