When you lose certain sensory cues, that you have been extensively conditioned/trained to interpret,.
As part of one of our Human Factors Workshops we were shown a video of an F-16 pilot in combat being locked up and fired upon by multiple SAM sites (he escaped). The interesting thing about the whole sequence (which lasted for around two minutes) was that all he had to do to escape the Missile Engagement Zone was take up a southerly heading - that was it, no requirement to pop chaff and flares, no altitude changes, no power changes - just fly South for thirty seconds. His wingman was yelling at him over the radio to follow him and fly south.
The pilot of the F-16 had reached a point of sensory overload, adrenalin was flowing, breathing rate had gone up and gotten shallower and he was scared - result, the higher brain functions had shut down and the guy was flying a fast jet using what the neuroscientists call "the caveman path". Didn't matter what he'd been conditioned/trained to interpret - as a species we have had millions of years to evolve but we are still hard wired to avoid being eaten by large animals on the African savannah - instinctively we know that the best way to avoid the large 300 pound tawny cat bearing down on us is to jink because we know it can outrun us in a straight line. As a result of his hard wired response, the pilot elected to jink his aircraft left and right but remain in the MEZ with missiles leaving contrails all around the aircraft. He eventually got a grip of his caveman instincts and flew south out of the MEZ.
It was a salutory reminder that even highly trained and conditioned people can reach overload under stress and that cockpits need to be designed bearing those situations in mind.