left superior frontal gyrus in patients with PD and VH. 8 Importantly, these reports compared patients with and without hallucination but did not actually scan any patient in the midst of an active hallucination. We believe that our study is the first to assess a patient with PDD by SPECT during VH. Our results demonstrated significantly increased rCBF in the left superior and middle temporal and inferior frontal gyri. Further, the pattern was not seen after treatment with neuroleptic and resolution of VH.
VH in our patient comprised well-formed objects such as humans, animals, and vivid complex visual images. The temporal lobe has been implicated in the generation of complex visual images, which may contribute to vivid, complex symptoms. 9 The superior and middle temporal gyri are involved in the integration of different types of visual information, 10 and the superior temporal gyrus has been suggested to have a role in the top-down control of visual processing, which might lead to VH. 11 Pathologically, high densities of Lewy bodies in the temporal lobes are strongly associated with florid VH in PD. 12 Our findings also suggested that the superior and middle temporal gyri are related to VH. Moreover, one functional study showed that hallucinating patients with PD had significantly greater cortical activity levels in the superior and inferior frontal cortices, including the frontal eye fields, during visual stimulation than non-hallucinating patients. 13 Our findings in the inferior frontal gyrus may also be related to VH.