It has been suggested that cognitive functions such as executive function would be associated with the manner of interregional relationship in D1R expression [15], and therefore it would be worthwhile investigating the interregional patterns of bindings for studies of neuropsychiatric disorders in which cognitive dysfunction based on DA system dysregulation is considered to exist, such as schizophrenia and Parkinson’s disease. Here, DRD1 is linked to schizophrenia.