Distractions, task prioritization, loss of situational awareness, or disorientation.

Bottom line

Once information flow exceeds the pilot’s ability to process the information mentally, any additional information becomes unattended or displaces other tasks and information already being processed. When a pilot becomes task saturated, there is no awareness of input from various sources, so decisions may be made on incomplete information and the possibility of error increases. When a work overload situation exists, a pilot needs to stop, think, slow down, and prioritize.