A selective imaging of tinnitus

WE selectively imaged the neural correlates of tinnitus, by contrasting a c ondition with no phantom auditory sensation with a condition during which t innitus is present, using a rare form of tinnitus elicited by eye movements . Using positron emission tomography (PET), we demonstrate that phantom aud itory sensation increases regional cerebral blood flow bilaterally in tempo ro-parietal association auditory areas but not in the primary auditory cort ex. These results confirm that conscious perception does not necessarily re quire activation in primary areas and suggest that the perceptual qualities of tinnitus, e.g. intensity, frequency and spatial localization, are repre sented in temporo-parietal regions. Activation in these regions is compatib le with cortical processing of ascending auditory messages generated at sub cortical levels. (C) 1999 Lippincott Williams & Wilkins.