Clinical anatomy of the precuneus and pathogenesis of the schizophrenia.

Recent evidence has shown that the precuneus plays a role in the pathogenesis of schizophrenia. The precuneus is a structure of the parietal lobe's medial and posterior cortex, representing a central hub involved in multimodal integration processes. Although neglected for several years, the precuneus is highly complex and crucial for multimodal integration. It has extensive connections with different cerebral areas and is an interface between external stimuli and internal representations. In human evolution, the precuneus has increased in size and complexity, allowing the development of higher cognitive functions, such as visual-spatial ability, mental imagery, episodic memory, and other tasks involved in emotional processing and mentalization. This paper reviews the functions of the precuneus and discusses them concerning the psychopathological aspects of schizophrenia. The different neuronal circuits, such as the default mode network (DMN), in which the precuneus is involved and its alterations in the structure (grey matter) and the disconnection of pathways (white matter) are described.

Cell adhesion molecules in the pathogenesis of the schizophrenia.

The causes of schizophrenia remain obscure and complex to identify. Alterations in dopaminergic and serotonergic neurotransmission are, to date, the primary pharmacological targets in treatment. Underlying abnormalities in neural networks have been identified as cell adhesion molecules (CAMs) involved in synaptic remodeling and interplay between neurons-neurons and neurons-glial cells. Among the CAMs, several families have been identified, such as integrins, selectins, cadherins, immunoglobulins, nectins, and the neuroligin-neurexin complex. In this paper, cell adhesion molecules involved in the pathogenesis of schizophrenia will be described.