The Effects of Task Load on Performance and Cerebral Blood Flow Velocity in a Working Memory and a Visuomotor Task

Abstract

This study examined the use of transcranial Doppler ultrasonography (TCD) as a tool to measure mental effort (as indexed by cerebral blood flow velocity) with increases in task load. Two tasks were chosen for this study based on their applicability to the task of piloting, a working memory (digit span) task and a visuo-motor tracking task. Based on previous findings of a possible relationship between mental workload and cerebral blood flow velocity it was hypothesized that both tasks would exhibit an increase in cerebral blood flow velocity in relation to baseline and that blood flow velocity would increase with increases in task demand. Although performance and subjective measures of mental workload indicated increased levels of effort to perform the digit span and tracking tasks as a function of task load, no systematic change in blood flow velocity was found with task demand in either task. Future work is needed to validate the use of TCD as a workload measurement tool.

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References

Aaslid

(1986). Transcranial Doppler examination techniques. In Aaslid

(Ed.), Transcranial Doppler sonography (pp.39–59). New York: Springer-Verlag.

Comstock

J. R.

Arnegard

R. J.

(1992). The multi-attribute task battery for human operator workload and strategic behavior research. Technical Memorandum 104174. NASA Langley Research Center, Hampton, VA.

Duschek

Schandry

(2003). Functional transcranial Doppler sonography as a tool in psychophysiological research. Psychophysiology, 40, 436–454.

Hitchcock

E. M.

Warm

J. S.

Matthews

Dember

W. N.

Shear

P. K.

Tripp

L. D.

Mayleben

D. W.

Parasuraman

(2003). Automation cueing modulates cerebral blood flow and vigilance in a simulated air traffic control task. Theoretical Issues in Ergonomics Science, 4, 89–112.

Mayleben

D. W.

(1998). Cerebral blood flow velocity during sustained attention. Unpublished doctoral dissertation, University of Cincinnati, Cincinnati, OH.

NASA Ames Research Center (1986). NASA Task Load Index (TLX): Paper and Pencil Version. Moffett Field, CA: NASA Ames Research Center Aerospace Human Factors Research Division.

Norman

D. A.

Bobrow

D. G.

(1975). On data-limited and resource-limited processes. Cognitive Psychology, 7, 44–64.

Nygren

T. E.

(1991). Psychometric properties of subjective workload measurement techniques: Implications for their use in the assessment of perceived and mental workload. Human Factors, 33, 17–31.

Oldfield

R. C.

(1971). The assessment and analysis of handedness. Neuropsychologia, 9, 97–113.

10.

Parasuraman

(2003a). Adaptive automation matched to human mental workload. In Hockey

G. R. J.

Gaillard

A.W.

Burov

(Eds.), Operator functional state: The assessment and prediction of human performance degradation in complex tasks. Amsterdam: IOS Press.

11.

Parasuraman

(2003b). Neuroergonomics: Research and practice. Theoretical Issues in Ergonomics Science, 4, 5–20.

12.

Parasuraman

Byrne

E. A.

(1996). Psychophysiology and adaptive automation. Biological Psychology, 42, 249–268.

13.

Parasuraman

Caggiano

(2002). Mental workload. In Ramachandran

(Ed.), Encyclopedia of the human brain. Vol. 3 (pp.1727). Academic Press.

14.

Scerbo

M. W.

Freeman

F. G.

Mikulka

P. J.

Parasuraman

Di Nocero

Prinzel

L. J.

III (2001). The efficacy of psychophysiological measures for implementing adaptive technology (Technical Report NASA/TP-2001-211018). Hampton, VA: NASA Langley Research Center.

15.

Stroobant

Vingerhoets

(2000). Transcranial Doppler ultrasonography monitoring of cerebral hemodynamics during performance of cognitive tasks: A review. Neuropsychology Review, 10, 213–230.

16.

Vingerhoets

Luppens

(2001). Cerebral blood flow velocity changes during dichotic listening with directed or divided attention: A transcranial Doppler ultrasonography study. Neuropsychologia, 39, 1105–1111.

17.

Wechsler

(1981). Wechsler adult intelligence scale-revised. New York: Psychological Corporation.