Objectives: The aim of this study was to investigate whether serum neurofilaments (Nfs),neuron-specific enolase (NSE) and S100 calcium binding protein B (S100B) in patients with chronic insomnia disorder (CID) were:(1) higher than those in healthy individuals;(2) lower in post-therapy CID patients than free-therapy patients;(3) associated with their impaired functions,including poor sleep quality,and reduced cognitive function (comprehensive cognition and memory performance in a specific task).