Citation

Szalma JL, Hancock PA. Proc. Hum. Factors Ergon. Soc. Annu. Meet. 2006; 50(16): 1609-1613.

Copyright

(Copyright © 2006, Human Factors and Ergonomics Society, Publisher SAGE Publishing)

DOI

10.1177/154193120605001620

PMID

unavailable

Abstract

Observers were provided the illusion of choice by permitting them to 'choose' an easy or a hard version of a vigilance task. Participants were then assigned at random to either the condition they expressed preference for or their non-preferred condition. Participants in the comparison control condition were not offered the opportunity to choose. Task demand was manipulated using event rate variation, divided into high and low event rates. Results indicated that permitting participants a choice regarding 'difficulty level' and subsequently assigning them to that level enhanced signal detections but did not reduce their perceived workload and stress. In contrast, offering a choice and then assigning observers to their non-preferred condition impaired performance relative to a condition in which no choice was provided. This pattern of effects was more pronounced at the low compared to the high event rate. These results confirm the importance of motivational effects in vigilance and the impact choice has on performance in tasks requiring sustained attention.

Language: en