Neural dynamics of distraction under competition in visual cortex

• Applicant: Professor Dr. Matthias M. Müller
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 495392039

The project aims to systematically investigate temporal neural dynamics of attentional resource allocation in competitive contexts. We studied competitive interactions of attentional resource allocation between top-down and bottom-up processes in early visual cortex indexed by top-down driven selective attention to a foreground task and bottom-up driven capture of attention triggered by emotional and non-emotional complex scenes. At the core of all studies is our conceptual framework "distraction under competition (DUC)" that integrates two influential concepts in cognitive neuroscience (i.e., sensory gain and biased competition) by the factor of time. During the first funding period, using Steady-State Visual Evoked Potentials (SSVEP). we completed 3 studies composed of 5 experiments. Results demonstrated a time delayed shift of attentional resources from the top-down driven foreground through competitive interactions that was preceded by a sensory gain bottom-up driven SSVEP amplitude enhancement of the emotional background distractors. Modeling of SSVEP amplitude dynamics with our proposed DUC model supported a time-delayed shift of attentional resources much better than the assumption of a time-invariant shift that is at the core of almost all contemporary attentional models. In the second funding period, we plan to manipulate saliency of background distractors in a more controlled manner compared to what is possible with complex scenes. To this end, we will use low-level stimuli such as groups of bars with different orientations that form a figure or Gabor patches for a more fine-grained saliency manipulation. This is motivated by our hypothesis that distractor sensory gain needs to cross a certain threshold to trigger competitive interactions with the foreground task. Our classical frequency-tagged SSVEPs distraction paradigm will provide a unique tool for further understanding neural temporal dynamics of competition as a function of distractor saliency. A second aim is to refine our modelling approach by implementing new and further control variables to model these predictions. At the end of the project, we are convinced that our work will not only further our understanding of competitive temporal neural dynamics in early visual cortex, but also might provide new theoretical ideas/guidelines for research in other fields, such as visual search or temporal attention or even for the modeling world, to incorporate such a time delayed process of facilitation and suppression into their models.

• DFG Programme: Research Grants