Mechanistic framework of how midbrain and forebrain networks interact to control spatial attention
By Prof Sridharan Devrajan, Senior Fellow
Indian Institute of Science, Bangalore
Our environment bombards us with an abundance of sensory information.Attention is our remarkable ability to select the most relevant information, at each moment in time, to shape behavior. Attention can operate through two distinct mechanisms -- by enabling us to perceive objects better (sensitivity), or by prioritizing the most important objects to engage with (bias). How these two mechanisms operate in the brain remains unknown. This study reveals that the bias mechanism is controlled by the superior colliculus, a highly conserved vertebrate midbrain structure. To demonstrate this, we developed a behavioral model for multi-choice attention tasks and analyzed data from many experiments that briefly activated or inactivated the superior colliculus during attention. These findings represent a key step towards understanding how attention works in the brain.
Does the Superior Colliculus Control Perceptual Sensitivity or Choice Bias during Attention? Evidence from a Multialternative Decision Framework. Devarajan Sridharan, Nicholas A. Steinmetz, Tirin Moore and Eric I. Knudsen. Journal of Neuroscience. January 2017