The “Zone of Proximal Development” (ZPD; Vygotsky, 1978) represents the difference between a learner’s current and potential levels of mastery. While in the ZPD, learners experience facilitating levels of workload, motivation, and anxiety. During scenario-based training, instructors often attempt to keep learners in the ZPD by dynamically modifying the scenario’s difficulty. Doing so, however, requires real-time measures of individual and team Cognitive Load (CL), which have been heretofore unavailable.
Using wireless COTS neurophysiological monitors, we generated real-time measures of Average Cognitive Load (ACL; the arithmetic mean of each team member’s CL) and Cognitive Load Balance (CLB; the extent to which one or more team members was significantly over- or under-loaded vs. the rest of the team). We then integrated these measures with high-definition video and expert observer ratings to provide a holistic view of team workload and performance.
The validation study included 16 medical teams. Three members of each team – the surgeon, the scrub nurse, and the anesthesiologist – were outfitted with the CL monitors. Each team completed several clinical simulations of varying (low, medium, and high) difficulty. During each simulation, we measured the teams’ ACL and CLB in real time. During a typical 12-minute scenario, we collected nearly 600 streaming CL values per measure, per team. In addition, expert observers rated the teams’ performance, and counted the number of appropriate and inappropriate technical behaviors. At the end of each scenario, the team members self-reported their perceived levels of stress and workload.
Mean ACL and CLB scores (calculated per team, per scenario) differentiated the low-, medium-, and high-difficulty scenarios, respectively. In addition, as the teams’ workload increased: observer ratings of the teams’ performance decreased; the number of appropriate technical behaviors decreased; the number of inappropriate technical behaviors increased; and self-reported workload and stress increased. Implications and lessons learned are discussed.