The Cost of Disruption: Analyzing the Impact of New Tasks on Time-Evolving Cognitive Activity

Certain aspects of cognitive state, such as attention, are known to oscillate and exhibit time-varying dynamics. This has strong implications for future human-system integration since, across domains, there is often a cost to interrupting ongoing processes. However, to date there is little knowledge about the cost of such disruption when considering cognitive resources. We have constructed a predictive model that captures these oscillations and predicts future cognitive state using only a finite history of prior state. We use this model to investigate what happens when ongoing cognitive dynamics are interrupted. We use data in which participants perform an unrestricted visual search task, while an auditory side task is randomly injected. The results show that when the timing of the side task causes a disruption, the participants’ physiology display patterns that have been previously associated with increased cognitive load. This indicates that it is not only the nature of the task that must be considered but also the onset time of the task. When task demands are out of phase with ongoing dynamics there is a cost to this timing error in addition to the challenge of the task itself.