A New Test of Scanning and Monitoring Ability: Methods and Initial Results

Civil Aerospace Medical Institute1992PDFTech ReportRevzin, A.M.Rasmussen, P.G.Civil Aeromedical InstituteUnited States. Office of Aviation MedicineCivil Aerospace Medical InstituteUnited StatesAir traffic controlHuman errorMonitoringAbilitiesVisionPerformance testsVigilanceAir traffic controlAbilityVigilance (Psychology)Performance--TestingVisionErrorsDOT/FAA/AM-92/12Most tasks in the FAA's Air Traffic Control (ATC) system involve long duration scanning and monitoring for continuously changing events occurring within a large visual space. Errors occur, so it is important to understand the causes of such errors to minimize or eliminate them by changing task design or improving personnel selection. This study describes a new system for testing scanning and monitoring abilities. The system, as currently implemented is basically a character identification task. The characters are presented at random intervals and locations within two or more "WorkAreas." The WorkAreas are defined as rectangular areas on a microcomputer display screen. They are filled with a constantly changing random dot pattern and may be located anywhere on the screen.The subject's task is to press a designated key on the computer keypad when a specified target character appears. Parametric manipulations can evaluate the effects on performance of many variables, including angular separation of WorkAreas, differential workloads in the WorkAreas, and effects of visual noise. We found a highly significant performance decrement as a function of increasing angular separation of WorkAreas. This is congruent with prior studies, which we interpret as a validation of our test procedure. We did not find practice effects, fatigue effects, or selective attention effects between WorkAreas.119