0234 Effects of a Post-Deprivation Nap on Peripheral Levels of Cortisol and Interleukin-6 Following 24-Hour Sleep Deprivation (original) (raw)

a MEGA-PRESS sequence within three a priori voxels of interest: the ventromedial prefrontal cortex (vmPFC), dorsolateral prefrontal cortex (dlPFC) and parietal-occipital region. Spectra were collected for a variety of brain metabolites, including gamma-Aminobutyric acid (GABA). MRS data were processed using LCModel software and expressed as a ratio to creatine. A 10-min psychomotor vigilance test (PVT) was administered hourly throughout SD. The first three PVT bouts served as a measure of baseline performance. Individual mean response speed on the PVT was normalized to baseline and used as an index of subject-specific resilience to SD. Due to technical complications, dlPFC MRS data was unavailable for n=9 subjects and parietal-occipital MRS data was unavailable for n=3 subjects. Results: A Pearson's partial correlation, controlling for gender, showed that baseline levels of GABA in the vmPFC were significantly correlated with resilience index (r=0.38, p=0.015), such that higher levels of GABA were associated with greater resilience. GABA levels in the dlPFC (r=0.17, p=0.358) and parietal-occipital region (r=0.15, p=0.389) were not significantly correlated with resilience. Conclusion: Subjects with higher versus lower GABA levels in the vmPFC were more resilient to PVT impairment during SD. These findings suggest that inhibitory neurotransmitters, such as GABA, are potential predictors of resilience to SD-induced performance impairment. Elevated levels of GABA in the vmPFC may reduce sensitivity to distractions, allowing for improved sustained attention and optimal performance. Support (If Any): 0234