Neuronal networks in mental diseases and neuropathic pain: Beyond brain derived neurotrophic factor and collapsin response mediator proteins

Abstract

The brain is a complex network system that has the capacity to support emotion, thought, action, learning and memory, and is characterized by constant activity, constant structural remodeling, and constant attempt to compensate for this remodeling. The basic insight that emerges from complex network organization is that substantively different networks can share common key organizational principles. Moreover, the interdependence of network organization and behavior has been successfully demonstrated for several specific tasks. From this viewpoint, increasing experimental/clinical observations suggest that mental disorders are neural network disorders. On one hand, single psychiatric disorders arise from multiple, multifactorial molecular and cellular structural/functional alterations spreading throughout local/global circuits leading to multifaceted and heterogeneous clinical symptoms. On the other hand, various mental diseases may share functional deficits across the same neural circuit as reflected in the overlap of symptoms throughout clinical diagnoses. An integrated framework including experimental measures and clinical observations will be necessary to formulate a coherent and comprehensive understanding of how neural connectivity mediates and constraints the phenotypic expression of psychiatric disorders.

Keywords: Neuron; Network; Synapse; Schizophrenia; Bipolar; Depression; Stress; Pain; Collapsin response mediator proteins

Core tip: Increasing evidences suggest that mental diseases are neural network disorders. Neurites and synapses represent the sub-cellular elements organizing these networks, and the molecules that regulate their formation, retraction and adaptive remodeling may contribute to the pathology of mental disorders. Various syndromes may share alterations of functional network leading to symptoms overlapping through clinical diagnoses.