What happens when we switch tasks: pupil dilation in multitasking

Area of Science:

• Cognitive Psychology
• Human-Computer Interaction
• Neuroscience

Background:

• Multitasking research often overlooks self-interruptions, despite their prevalence in real-world work.
• Understanding the cognitive load of self-initiated task switching is crucial for optimizing work environments.

Purpose of the Study:

• To contrast the cognitive processes involved in self-interruptions versus external interruptions.
• To investigate the temporal dynamics and costs associated with the decision to self-interrupt during multitasking.

Main Methods:

• Three multitasking experiments were conducted, measuring pupil size changes during task switching.
• Participants engaged in primary and secondary tasks, with conditions involving self-initiated and externally-initiated interruptions.

Main Results:

• Increased pupil dilation was observed seconds before self-interruptions, suggesting a significant decision-making period.
• Participants were significantly slower in self-interruption blocks compared to external interruption blocks.
• The decision to switch tasks incurs a cognitive cost, impacting performance speed.

Conclusions:

• The cognitive decision to self-interrupt is time-consuming and costly.
• Task switching efficiency may be improved through targeted training interventions.
• Implementing forced task switches after subtask completion could enhance overall productivity over user-initiated switches.