Research Summary

Cortical and sub-cortical mechanisms of visuospatial selective attention

The natural world inundates our senses with copious information. The capacity for selective attention enables us to “select” the most important information, while “filtering" out irrelevant, distracting information. What are the neural mechanisms by which attention works in the brain, and how do these mechanisms shape behavior?

Here, we seek to understand how key cortical and sub-cortical brain regions — prefrontal cortex (PFC), posterior parietal cortex (PPC), superior colliculus and thalamus — interact to control attention. We propose that these brain regions dynamically organize into functionally coupled networks to enable distinct aspects of attention control: target enhancement and distractor suppression via sensitivity and bias control. Additionally, we will investigate how neural oscillations, in the gamma and alpha frequency ranges, in these regions contribute to attention.

To address these objectives we will employ cutting-edge neurotechnologies: functional MRI (fMRI) and diffusion-weighted MRI to characterize brain activity and connectivity, concurrent electrophysiology and fMRI (EEG-fMRI) to identify neural sources of gamma and alpha oscillations, and concurrent transcranial magnetic stimulation and fMRI (TMS-fMRI) to identify the causal role of these brain regions and brain oscillations in attention. The results will advance our understanding of how attention works in the brain, both in health and disease.

Figure Legend: (Left) Activation of the prefrontal cortex and parietal cortex (top) and the default-mode network (bottom) as measured with functional magnetic resonance imaging (fMRI) during an attention task. (Middle) Whole brain connectome as measured with diffusion MRI followed by tractography. (Right) Alpha-band oscillations measured with scalp electroencephalography (EEG) Briefer legend: The brain's functional connectivity (left), anatomical connections (middle) and oscillatory dynamics (right) during attention, as measured with magnetic resonance imaging and electroencephalography.