Positron Emission Tomography in Schizophrenia: A New Perspective

Abstract

PET is an important functional imaging technique that can be used to investigate neurotransmitter receptors and transporters directly by mapping human brain function. PET is increasingly being used greatly to advance our understanding of the neurobiology and pathophysiology of schizophrenia. Methods: This review focuses on the use of PET tracers and kinetic modeling in identifying regional brain abnormalities and regions associated with cognitive functioning in schizophrenia. A variety of PET tracers have been used to identify brain abnormalities, including 11 C, 15 O-water, 18 F-fallypride, and L-3,4-dihydroxy-6-18 F-fluorophenylalanine ( 18 F-FDOPA). Results: Some studies have used compartmental modeling to determine tracer binding kinetics. The most consistent findings show a difference in the dopamine content in the prefrontal cortex, anterior cingulate gyrus, and hippocampus between healthy controls and patients with schizophrenia. Studies also show a higher density of D 2 receptors in the striatum and neural brain dysconnectivity. Conclusion: Future investigations integrating clinical, imaging, genetic, and cognitive aspects are warranted to gain a better understanding of the pathophysiology of this disorder.

Prefrontal Cortex Governs Normalcy and Psychiatric Illness: Neuroimaging Evidence

“…This is consistent with the observations from studies of people with schizophrenia and obsessive-compulsive disorder [5,15].…”

“…Diminished metabolic activity in prefrontal cortex has been shown in schizophrenia [14][15][16], depression [9,17], in depression associated with diabetes [18], depression associated with Parkinson's disease, depression associated with stroke, depression associated with Huntington's disease, bipolar disorder [19], addictive behavior [20], obsessivecompulsive disorder [21], chronic pain [22]. Reduced functional connectivity within cortical limbic loop has been shown in obsessive compulsive disorder [23,24] and depression [9,17,25].…”

What insights can we gain from studying early-onset schizophrenia? The neurodevelopmental pathway and beyond

“…Few studies have used positron emission tomography to investigate neurobiological and neurochemical mechanisms underlying EOS [14], possibly because of ionizing radiation exposure and the need for ready access to a cyclotron (for a review, see [57]). …”

Theory of Mind in the Early Course of Schizophrenia

“…Several lines of evidence support a dysregulation of subcortical dopamine system as an etiology of schizophrenia [104][105][106]. The role of dopamine transmission in impairments in the ToM in schizophrenia has been explored between genes encoding dopamine receptor D2 (DRD2) and the enzyme of catecholamine metabolism, catechol-Omethyltransferase (COMT).…”