The impact of auditory task complexity on primary task performance in military land vehicle crew

Military land vehicles are becoming more technologically advanced, offering much greater capabilities for command and control on the move. The capabilities afforded by these modern vehicles are likely to place greater cognitive demands on the vehicle operators, and an increased requirement for vehicle crews to communicate effectively. This study explored the influence of a secondary task load on both individual and crew performance. Eight driver/co-driver crews operated a driving simulator over two days, during which the complexity of an auditory secondary task, which incorporated a crew-based communication component, was manipulated. The impact of this manipulation on both individual and crew performance was assessed. The results suggest that participants prioritized and protected performance on their primary task when the complexity of the secondary task was increased, at the cost of declines in their secondary task performance. Implications for the use of modern land vehicles in defense fleets are discussed, along with our research program aimed at further exploring the impact of varying cognitive load on crew performance.