Cognitive Workload Research

Goal: Understanding the mechanism of cognitive workload while multitasking, the impact of the secondary task and of the individual difference of cognitive ability

My work: Performed the entire process, from setting the theme, planning and designing the research, preparation, recruiting, conducting experiments and surveys, to data analysis and reporting. 

Outcomes: Delivered the study results, insights obtained, and design implications to ToyotaITC. Here are some examples of design implications:

• Interactions that require touching specific locations have high visual demand and are unsuitable for multitasking situations. Gestures that function anywhere on the screen are preferable.

• While the participants were busy for the primary task (driving), a "batch processing" approach for the secondary task was observed: Instead of progressing one command at a time while receiving system feedback, users frequently exhibited behavior where they pre-planned and submitted several commands in advance. To facilitate such batch processing interactions, an interface where the outcome of actions can be predicted is preferable. (For example, presenting information in increments, skipping a certain number of items at a time instead of continuous scrolling.)

• In voice navigation, "grasping the current position (in the menu structure)" is a challenge. It is considered effective to have features that always return to a fixed position or go back to the last selected option. Setting several reference points is beneficial.

In addition to the project reports, the following international conference papers were published.

[1]   Jiang, H., Mizobuchi, S., & Chignell, M. (2023, October). Lower Executive Function Ability May Lead to Higher Perceived Mental Workload in Driving Scenarios. In Proceedings of the Human Factors and Ergonomics Society Annual Meeting (p. 21695067231192859). Sage CA: Los Angeles, CA: SAGE Publications. https://journals.sagepub.com/doi/pdf/10.1177/21695067231192859

[2]  Mizobuchi, S., Chignell, M., Delange, T.,  and Ho, W. (2014) Sensitivity of a Voluntary Interruption of Occlusion Measure to Cognitive Distraction During a Pedal Tracking Task, Proceedings of the Human Factors and Ergonomics Society Annual Meeting September 2014 (HFES2014), vol. 58 no.1,  pp. 2229-2233. doi:10.1177/1541931214581468. https://doi.org/10.1177/1541931214581468

[3]   Mizobuchi, S., Chignell, M., Canella, D., Eizenman, M., Yoshizu, S., Sannomiya, C., and Nawa, K. (2013) The Effect of Secondary Task Timing and Difficulty on Driving-Related Performance and Modality Selection, Proceedings of the 20th ITS World Congress Tokyo 2013, No. 4171. https://trid.trb.org/view/1322507

[4]   Mizobuchi, S., Chignell, M., Canella, D., Eizenman, M., Yoshizu, S., Sannomiya, C., Nawa, K. (2013) Looking or Listening? : Impacts of Secondary Task Timing and Difficulty on Tracking Performance, Proceedings of the Human Factors and Ergonomics Society Annual Meeting September 2013 (HFES2013), vol. 57 no. 1, pp.1894-1898.  https://doi.org/10.1177/1541931213571422 

[5]   Mizobuchi, S., Chignell, M., Canella, D., and Eizenman, M (2013) Individual Differences in Driving-Related Multitasking, Proceedings of the 3rd International Conference on Driver Distraction and Inattention (DDI2013), No. 72-P. http://www.distractionconference.com/ddi2013-en/program/program-papers

[6]   Mizobuchi, S., Chignell, M., Suzuki, J., Koga, K. & Nawa, K. (2013) Shifting Between Cognitive and Visual Distraction: The Impact of Cognitive Ability on Distraction Caused by Secondary Tasks, Proceedings of the 7th International Driving Symposium on Human Factors in Driver Assessment, Training and Vehicle Design (DA2013), pp142-148. https://doi.org/10.17077/drivingassessment.1480

[7    Mizobuchi, S., Chignell, M., Suzuki, J., Koga, K. & Nawa, K. (2012) The Impact of Central Executive Function Loadings on Driving-Related Performance,  Adjunct Proceeding of the third conference on automotive user interface and interactive vehicular applications (Automotive UI 2012), pp. 68-75. https://www.auto-ui.org/12/proceedings.php

[8]    Mizobuchi, S., Chignell, M., Suzuki, J., Koga, K. and Nawa, K. (2011) Central Executive Functions Likely Mediate the Impact of Device Operation When Driving, Proceeding of the third conference on automotive user interface and interactive vehicular applications (Automotive UI 2011), pp. 129-136. https://doi.org/10.1145/2381416.2381437