Neuroimaging on methamphetamine users with psychiatric symptoms

A long-term abuse of methamphetamine causes psychiatric symptoms, such as psychosis and anxiety disorder-like symptoms. Some of the symptoms are persistent for long time of period even after cessation of the methamphetamine use. We employed positron emission tomography (PET) studies to clarify the changes in the brain dopaminergic systems of methamphetamine abusers and the relations of the changes to their psychiatric symptoms. It was indicated that persistent reduction of dopamine transporter density in the caudate/putamen, nucleus accumbens and prefrontal cortex in the abusers, whereas the density of dopamine D2 receptors were not different from the control subjects. The results also suggested the reduction of dopamine transporter density may be closely associated with duration of methamphetamine use and severity of persistent psychiatric symptoms in methamphetamine users.