Why do parietal cortex neurons become more active when an animal pays attention to a visual target?

Neurons in the parietal cortex exhibit increased activity when an animal pays attention to a visual target because these neurons are highly dependent on the state of vigilance. When an animal is merely waiting or lacks a specific focus, these neurons remain inactive or minimally active. However, when the animal is actively looking at a visual target to detect a change and obtain a reward, the neurons become engaged to facilitate the task.1

This activity is part of a broader tracking system involving the superior colliculus and the temporal and parietal cortices, which enables the eyes and head to follow moving objects and maintain them within the visual field. While some parietal neurons respond to specific visual stimuli or eye movements, their heightened response during goal-oriented behavior reflects the recruitment of neural resources necessary to process task-relevant information and perform the required action.12