Assessing workload in neuropsychology: An illustration with the Tower of Hanoi test

ABSTRACT

Workload is a common and useful construct in human factors research that has been largely overlooked in other areas of psychology, including neuropsychology, where it could be effectively employed both theoretically and practically. A popular subjective measure of workload, the NASA-Task Load Index (NASA-TLX), is illustrated with a computerized version of the Tower of Hanoi (TOH), a typical neuropsychological test of executive function. Reported workload, especially as an overall measure and also for the Mental Demand and Effort subscales, was greater in the more difficult TOH conditions and was positively correlated with number of moves to complete the TOH as well as completion time. Thus, results support the utility or construct validity of the NASA-TLX in reflecting workload states in the individual as well as various demands of the neuropsychological test (the timing, physical demands, etc.). It is argued that workload can be a useful construct in neuropsychological assessment, providing an additional channel of information on patient status. For instance, what does it mean if test performance for a patient is at a typical level (indicating no deficit) but workload is exceptionally high?

KEYWORDS:

• Workload
• mental workload
• assessment
• NASA-Task Load Index
• neuropsychology

Acknowledgments

This paper is partially based on several previous presentations, including Hardy, Spielberg, and Wright (2015) and Hardy et al. (2015). For assistance in data collection, presentations, and so on, we thank (in alphabetical order) Mark Barrett, Chelsea Cowley, Jennifer Hoy, Carlee Kreisel, Jessica Nunnally, Alice Gaverette Olvera, Cassidy Reilly, Joel Schreiber, Travis Scott, Tristan Sguigna, Kimberly Smith, Benjamin Spielberg, and Patricia Stark.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. Three publications in Neuropsychologia involved the concept and term mental workload or workload, but all of these were purely basic cognitive neuroscience studies, none of them included any patients, and all used experimental tasks.

2. Tower of Hanoi performance in the 4-disk TOH, the task setup used in Mataix-Cols and Bartrés-Faz (2002), was fairly comparable in both studies, with their results ranging from a mean of 27.0 moves (SD = 8.9) to 29.9 moves (SD = 16.9). The slightly better performance in our results (M = 25.53, SD = 10.34) could be due to greater overall practice; participants in our study completed the TOH three times versus twice in Mataix-Cols and Bartrés-Faz (2002).