Neural Correlates of Narcolepsy Disorder: An Activation Estimation Likelihood Meta-Analysis

Narcolepsy, a second prevalent sleep disorder, is characterized by excessive daytime sleepiness, lack of muscle tone triggered by strong emotions that is called cataplexy, sleep paralysis and hallucinations. [1] Narcolepsy also impairs the quality of life and productivity of patients, and increases the risk of accidents. [2] Several structural and functional neuroimaging studies have been conducted in patients with narcolepsy, but they have reported diverse results. Thus, we aimed to determine convergent patterns of abnormal brain function and structure of narcolepsy disorder. Method Based on the preferred reporting for systematic reviews and meta-analyses statement, we had studied 1931 papers from PubMed, Scopus and Ovid databases and retrieved 19 eligible neuroimaging studies. Then, we performed activation estimation likelihood (ALE) meta-analysis to test the convergence among their findings. [3]Results We mainly found a cluster of 73 voxels that shows structural atrophy and dysfunction in frontal orbital cortex, right amygdala and Parahippocampal gyrus - anterior division (p-value 0.007). Conclusions These regions are associated to processing of memory, emotion and decision making. Therefore, these regions and functions play a key role in pathophysiology of narcolepsy.