Humans increasingly use automated decision aids. However, environmental uncertainty means that automated advice can be incorrect, creating the potential for humans to action incorrect advice or to disregard correct advice. We present a quantitative model of the cognitive process by which humans use automation when deciding whether aircraft would violate minimum separation. The model closely fitted the performance of twenty-four participants, whom each made 2400 conflict detection decisions (conflict vs non-conflict), either manually (with no assistance) or with the assistance of 90% reliable automation. When the decision aid was correct, conflict detection accuracy improved, but when the decision aid was incorrect, accuracy and response time were impaired. The model indicated that participants integrated advice into their decision process by inhibiting evidence accumulation toward the task response incongruent with that advice, thereby ensuring that decisions could not be made solely on automated advice without first sampling information from the task environment
