1) To understand how subcortical structures that encode reward predictions, and cortical structures that underpin visual attention operations, interface when sensory cues predict future decision-related outcomes.
The fellow has successful applied state-of-the-art modelling of neural circuitry to determine that the striatum modulates its influence on cortical activity when expectations predict decision-related outcomes. The fellow has compared theories for how the brain may encode and combine distinct expectations to guide visual selection, and has found that that expectations are encoded independently to influence visual selection, suggesting summation of expectations to build priorities for visual exploration across any scene. She has further identified that individuals for systematic subtypes in how they are influenced by value cues, with some people showing a reactive, counterfactual response, rather than an anticipatory coding of the visual scene. The fellow has completed data collection for a high-resolution imaging study that assesses the extent to which information pertaining to visual expectations is present in the striatum.
2) To ascertain whether a causal role can be established for subcortical brain regions when such predictions guide visual-selection
The fellow has developed a paradigm and a methodology to assess the causal role of the systems governed by the basal ganglia, in healthy participants, using a dopamine-intervention study. This has resulted in the formation of a novel collaboration. The study is registered on the open science framework.
3) To understand the scope of striatal influence on the cortical dynamics (i.e. ongoing neural communication) that underpin visual attention operations
The fellow has established the protocols for this study and has run a development version using EEG (in preparation for MEG). The results of this project have established that the brain normalises across learned value associations to influence visual priorities across a visual scene, and that this occurs to update violated expectations, rather than in anticipation to upcoming visual events. These results are currently being written up for publication. The fellow has also collaborated to identify that asymmetries in striatal structure predict visual attention biases as captured in the oscillatory dynamics of the MEG signal.
The action has resulted in 3 publications (Journal of Cognition, eNeuro, Attention, Perception & Psychophysics), a textbook chapter, 6 conference presentations, 8 invited talks, and 4 newspaper articles/media interviews.
