Circuit mechanisms of attention control Animals and humans are subjected constantly to overwhelming barrage of information from the environment, while processing capacity of their nervous system is limited. To overcome this dilemma, their brain dynamically selects and processes, in more detail, the most important stimuli in expense of ignoring others. Several networks in the midbrain and the forebrain are known to be involved in selection of the location for directing gaze and attention. However, how these networks perform required computations is less understood. Here, I will discuss neural computations for competitive stimulus selection in the avian midbrain gaze circuitry. The midbrain network in birds is anatomically well characterized and includes the Optic Tectum (OT; Superior Colliculus (SC) in mammals) and distinct cholinergic, GABAergic and glutamatergic nuclei in the lateral tegmentum. The neurons of these nuclei comprise neural maps of space, encode the relative strengths of stimuli across the entirety of space and many of them differentially signal the location of the strongest stimulus in a switch-like way. The functional properties of these neurons resemble those of a salience map, a core component in computational models for spatial attention and gaze control.

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