title: Rapid functional imaging of emotional perception
speaker: Dean Sabatinelli, Department of Psychology & Bioimaging Research Center, Univeristy of Georgia
Human and animal research supports a perspective in which the emotional discrimination of visual stimuli originates via transaction between amygdala and inferotemporal visual cortex (IT). Work in our lab has used very fast functional MRI (100 – 300 ms) to identify changes in hemodynamic signal intensity during emotional and nonemotional picture perception to support this model, and begin to describe the relative activation timing across a range of neural structures relevant to the emotional discrimination process. Recent work includes combines 4 successive 4-slice functional acquisitions (yielding an effective whole-brain sampling rate of 300 ms) with an in-out spiral functional pulse sequence in an effort to maintain temporal resolution and maximize data quality in orbitofrontal cortex (OFC), a cortical region implicated in animal studies of emotional learning. Data from a large sample of healthy participants replicates the relative timing of emotional discrimination in amygdala, IT, frontal eye fields, and intraparietal sulcus, and suggests an early OFC sensitivity to scenes of threat, concomitant with amygdala.