SPECT data in a case of secondary Capgras delusion.

Capgras' delusion (CD) may be secondary to a neurologic lesion, particularly in the right frontal or occipital regions. A 40-year-old woman with multiple sclerosis underwent SPECT during and after an episode of CD. Analysis during delusion showed an uptake defect in the right parietal cortex with an 11% index of asymmetry (normal: < or = 4%). Post-delusion SPECT showed decreased bifrontal and biparietal cortical uptake indices but a normal index of asymmetry. Functional brain imaging may provide clues to the psychopathology of CD.