title:
Rapid functional imaging of emotional
perception
speaker:
Dean Sabatinelli, Department
of Psychology & Bioimaging Research Center, Univeristy of Georgia
abstract:
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.