Poster E123, Monday, March 27, 2:30 – 4:30 pm, Pacific Concourse
Tagging the neurophysiological mechanisms of competition between task-relevant and concurrent emotionally arousing task-irrelevant visual information using simultaneously recorded electrocortical and hemodynamic signals
Nathan Petro1, L. Forest Gruss1, Siyang Yin1, Mingzhou Ding1, Andreas Keil1; 1University of Florida
Task-irrelevant emotional stimuli lead to decreased performance on concurrent visually cued task-relevant stimuli, suggesting that emotionally arousing information attracts attention at the cost of less emotional yet task-relevant stimuli. This cost is associated with attenuated electrocortical potentials evoked by task-relevant visual cues. However, not well understood are the precise neurophysiological networks which underlie cost-related changes in visuocortical activity and the resolution of competition to maintain attention toward task-relevant visual information. The current project recorded electroencephalography during simultaneous functional magnetic resonance imaging, to co-register temporally precise evoked electrocortical potentials with the exquisite spatial resolution of hemodynamic changes. Participants were instructed to report instances of coherent among otherwise incoherent motion of a random-dot kinematogram, which flickered on-and-off at a rate of 4.6 Hz for a duration of 11.61 seconds to drive a steady-state visual evoked potential (ssVEP), a measure of continuous visuocortical engagement, while a concurrent and spatially overlapping background picture depicting scenes varying in emotional valence was presented and flickered on-and-off at 6 Hz, driving a separate ssVEP. These two ssVEPs, when transformed into the frequency domain and estimated on a single trial basis, can separately index the visuocortical processing of the task-relevant and -irrelevant stimuli. These estimates were used to construct predictive models of whole-brain BOLD activity. Ongoing analyses indicate that task-relevant ssVEPs predict BOLD in circumscribed visual and anterior cortical sites, whereas task-irrelevant pictures predict activation in more widespread visual and temporal cortex. Future analyses aim to identify how these regions interact toward resolving competition costs.
Topic Area: PERCEPTION & ACTION: Vision