Contributions of Body-Bound, Brain-Bound, and Control Resources to Cognitive Workload
I will discuss parts of two experiments designed to test the relative impact of body-bound (e.g., eye movements, motor movements), brain-bound (e.g., memory, visual, auditory), and control (proactive versus reactive) processes on dual task performance. Experiments were conducted in a paradigm that combines a visual tracking task with an n-back style memory task with Experiment two imposing the same demands on body-bound components across high and low workload conditions. Results suggest that eye movement behavior, and not an overload of visual processing cause most of the effects discovered. However, memory load seems to affect the brain's ability to exert proactive control over eye movements, resulting in hard to predict performance effects. These results are analyzed at the timescale of immediate interactive behavior and suggest that understanding these control functions may be the key to understanding how workload affects performance in a variety of tasks.