[Functional magnetic resonance tomography of psychological functions exemplified by experimentally induced emotions]

Changes in regional cerebral blood oxygenation during experimentally modified psychological activation can be measured with functional magnetic resonance imaging (fMRI). fMRI is a new imaging technique for perfusion-based signal intensities of the brain without the necessity of radioactivity and with superior anatomical and temporal resolution compared to positron emission tomography (PET). In this study a T2* FLASH sequence (TR 240ms, TE 60ms, slice thickness 4 mm, alpha = 40 degrees, matrix 64 x 128) was used to investigate changes in signal intensity within the temporal lobe and the amygdala during experimentally induced emotions. Visual stimuli of happy [sad] facial portraits were presented to volunteers to induce changes in the subjects' mood while lying in the tomograph. In agreement with a previous PET study, a significant increase in signal intensity in the left amygdala was found during induction of a sad mood, while no comparable effect was visible during induction of a happy mood.