The current study presents an alternate method of analyzing PET data by means of a correlational approach. Correlational or coupling patterns of regional cerebral glucose metabolism were found for normal subjects and patients with schizophrenia under electric shock stimulation. At two levels (91 mm and 78 mm) significant differences were found between the coupling patterns of normal subjects and patients with schizophrenia. For the normals, the obtained correlational maps were consistent with the sensory input. However, such patterns were not found for the patients with schizophrenia. Therefore it is suggested that the outlined analysis procedure may complement the standard approach of comparing the mean metabolic rates.