2010 Fiscal Year Final Research Report
MR-Tractography study of the pathogenesis of arousal impairment in hypersomnia
Project/Area Number |
21791161
|
Research Category |
Grant-in-Aid for Young Scientists (B)
|
Allocation Type | Single-year Grants |
Research Field |
Psychiatric science
|
Research Institution | 財団法人神経研究所 (2010) Neuropsychiatric Research Institute (2009) |
Principal Investigator |
NAKAMURA Masaki 財団法人神経研究所, 研究部, 研究員 (70375054)
|
Project Period (FY) |
2009 – 2010
|
Research Abstract |
We applied the voxel-based statistic approach by SPM8 for FA/ADC image and gray/white matter images obtained on MRI to estimate the brain microstructural change in narcolepsy and idiopathic hypersomnia, both which chief compliant is excessive daytime sleepiness. As a results, narcolepsy, regardless with or without cataplexy, showed reduced white matter volume of midbrain where the neural nuclei associated with maintenance of arousal exist, higher ADC in bilateral amygdala and left medial frontal area. Sleep efficiency showed negative correlation with ADC and FA in mainly right limbic area. These results indicate that the degree of axonal change is related with the disturbance in sleep maintenance system. Additionally, the pathogenesis of cataplexy might associated with abnormality in right precentral gyrus, right inferior frontal gyrus, right precuneus and left cerebellar tonsil. On the other hand, idiopathic hypersomnia showed FA abnormality in white matter distally along cerebral cortex of occipital, frontal and temporal area. As a conclusion, the mechanism of excessive daytime sleepiness is thought to be distinct between narcolepsy and idhiopathic hypersomnia.
|