Attention Network Test (ANT)

Attention is often subdivided by researchers into a number of separate systems. Although there is certainly some interaction between them, these systems play different roles in terms of their effect on information processing and the control of behavior. Further, there is evidence that different attentional systems are associated with different, largely nonoverlapping brain regions and rely to a large extent on different neurotransmitter systems. One such framework advanced by Michael Posner and colleagues defines three separate attention systems or networks: alerting, orienting, and executive control.

The alerting system is responsible for helping the organism reach and maintain an alert state. This state, which is separate from arousal, is characterized by a readiness to perceive and process incoming stimuli. The alerting system has been associated with superior parietal, right frontal, and thalamic brain regions and the norepinephrine neurotransmitter system.

The orienting systemis...