الفهرس 
Anatomy of the BrainOnly 14 pages are availabe for public view
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Abstract
Schizophrenia is a prevalent psychiatric disorder. It is one of the world’s 10 leading causes of disability assessed by DALYs scale, and despite current progress in research and treatment, continues to be a major etiologic, diagnostic, and therapeutic challenge. It has been estimated that around 1% of the world population suffers from this chronic and disabling disorder (1). The onset of schizophrenia usually occurs in late adolescence or early adult life, meaning great losses in educational, social, and economic outcomes for individuals and for society as a whole. Currently available evidence suggests that schizophrenia occurs as the result of a combination of genetic, environmental, and social risk factors (2, 3). The clinical presentation of schizophrenia is heterogeneous and its manifestations vary among patients and during the course of the disorder. Symptoms can be divided into five dimensions or syndromes: positive (delusions and hallucinations), negative (affective flattening, avolition, social isolation, and alogy), cognitive (executive dysfunction, memory and attention), disorganization (disorganized speech and behaviour) and affective (depression, anxiety, dysphoria and mania) (4, 5). Functional neuroimaging studies have proved to be an invaluable source of information about the physiopathology of schizophrenia. Many of these studies use radiation-based tracers, like positron emission tomography (PET) and single-photon emission computed tomography (SPECT). In addition, a growing number of studies have been carried out using newer functional magnetic resonance imaging (fMRI) methods that are able to effectively evaluate brain function without the use of radiation. Bloodoxygen level dependency (BOLD) and arterial spin labeling (ASL) are among these methods.