Real-Time Assessment of Mental Workload Using Psychophysiological Measures and Artificial Neural Networks

By Wilson, Glenn F.; Russell, Christopher A. | Human Factors, Winter 2003 | Go to article overview

Real-Time Assessment of Mental Workload Using Psychophysiological Measures and Artificial Neural Networks


Wilson, Glenn F., Russell, Christopher A., Human Factors


INTRODUCTION

Modern complex systems can place very high cognitive demands upon their operators. The rate of information flow, the complex nature of this information, and the number and rate of required decisions can overwhelm the human operator. At the other end of the continuum, automation of tasks can lead to operator complacency and errors of inattention (Billings, 1997). However, current systems are capable of modifying themselves to meet the momentary needs of the operator. This includes assuming some task functions until the operator's mental load is reduced. In other cases, systems can adjust to improve the operator's awareness to relieve boredom or inattention. Adaptive aiding based on the current functional state of the operator can be most beneficial when supplied at the appropriate time and with the consent of the operator (Rouse, 1988). Further, accurate assessment of operator functional state is required in the test and evaluation of new and modified systems (Charlton & O'Brien, 2002). In these situations the critical factor is the accurate and reliable assessment of the operator's functional state. The functional state of an operator is defined as his of her ability to carry out the job at that moment in time.

One method of monitoring operator functional state is by examining the operator's physiology. The various physiological measures provide unique information about several aspects of operator state. Eye blink rate contains valuable information with regard to the visual demands of tasks. Heart rate is useful to determine the operator's global response to task demands (Wilson & Eggemeier, 1991). The electroencephalogram (EEG) provides useful information about both high workload and inattention (Gundel & Wilson, 1992; Kramer, 1991; Sterman & Mann, 1995; Wilson & Eggemeier, 1991). EEG measures have been used to classify patients with regard to types of neuropathy and psychiatric disorders using linear statistical techniques (John, Pricep, Fridman, & Easton, 1988) and artificial neural networks (ANNs; Kloppel, 1994). EEG has also been used to classify drug effects and to detect alcohol intoxification and fatigue (Gevins & Smith, 1999; Herrmann, 1982). Physiological signals are always present and can be unobtrusively collected and, thereby, are able to provide uninterrupted information about operator state (Wilson, 2001, 2002).

Several studies have used psychophysiological measures to classify operator state with regard to mental workload. Most of these studies have employed EEG, cardiac, and eye data. Several of these studies used either simple, single-task paradigms (Gevins et al., 1998; Gevins & Smith, 1999; Nikolaev, Ivanitskii, & Ivanitskii, 1998; Wilson & Fisher, 1995) of relatively few peripheral nervous system variables in the context of complex task performance (Wilson & Fisher, 1991). Others have used complex tasks with skilled operators (Russell & Wilson, 1998; Russell, Wilson, & Monett, 1996; Wilson & Russell, 2003). These papers report overall successful task classification in the 80% to 90% correct range. The success rate of correctly classifying high mental workload or altered operator state is very encouraging. This suggests that these methods could be used to provide accurate and reliable operator functional state assessment during test and evaluation and to implement adaptive aiding systems. Hilburn, Jorna, Byrne, and Parasuraman (1997) used psychophysiological measures to show that adaptive aiding controlled by the task demands of their air traffic control task reduced mental workload. This demonstrates that psychophysiological measures of operator functional state change to show reduced mental workload when adaptive aiding is applied.

Psychophysiological measures have also been used to implement adaptive aiding in laboratory situations designed to detect lowered operator engagement in the task being performed (Freeman, Mikulka, Prinzel, & Scerbo, 1999; Freeman, Mikulka, Scerbo, Prinzel & Clouatre, 2000; Pope, Bogart, & Bartolome, 1995; Prinzel, Scerbo, Freeman, & Mikulka, 1995). …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Real-Time Assessment of Mental Workload Using Psychophysiological Measures and Artificial Neural Networks
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.