The pulvinar nucleus of the thalamus in the brain processes information about attended targets, while gating out information about unattended targets. These findings, reported in Nature Communications this week, reveal new insights into how the brain maintains visual attention.
The pulvinar nucleus has long been implicated in visual attention. However, much of this insight has been gained from subjects who have suffered lesions to the pulvinar nucleus, such as stroke patients. Jason Fischer and David Whitney image the brains of healthy human subjects while they are presented with visual stimuli. They find that when behaviourally relevant stimuli compete for attentional resources within the same visual field of each subject, the pulvinar nucleus becomes activated by attended objects rather than by ignored objects. They note that the visual cortex responds to both attended and ignored targets, and so these findings reveal a unique role of the pulvinar nucleus in filtering out visual distracters.