Luke Tousignant

What does hemispheric spatial neglect tell us about the role of attention in visual feature binding?

Started June 10, 2025

Abstract or project description

The human brain allows us to combine distinct sensory inputs into a unified perception. This process, known as feature binding, relies on complex neural architecture. In visual processing, these functions include the coordination of visual information with spatial awareness. The parietal cortex is thought to be a critical brain region for visual feature binding, and particularly critical for spatial attention. Spatial attention can be thought of as a mental frame that holds shards of information together. When it acts, it organizes all the information we take in, and links it together, creating our unique experience. When this framework is disrupted, your perception crumbles, and can’t link features properly. Here we show that damage to the parietal cortex leads to binding failures due to the impairment of the brain’s ability to direct and apply spatial attention, as demonstrated through behavioral experiments and neuroimaging studies. In particular, lesion studies offer insight into how damage to the area results in a distorted perception. Conditions such as hemineglect and Balint’s Syndrome, which arise from lesions in the parietal cortex, present consistent evidence of binding failure due to attentional impairment. These findings demonstrate attention’s key role in visual feature binding. Evidence from brain lesion studies additionally demonstrates the parietal cortex’s key role in visual attention. Together, these functions construct our perception, without which our visual reality weakens.