When measuring operator states the predictive power of cardiovascular and respiratory measures in relation to mental workload has been questioned. One of the main questions is to what extent do cardiovascular measures actually reflect mental workload. This question arises because good measures of mental workload should be sensitive to changes in mental effort alone and not to other influences o...

The importance of the reuse of components and materials from post-consumer products has been widely recognized in the literature and in practice. In this paper, we address the problem of choosing the appropriate channel structure for the recollection of post-consumer products from customers. Specifically, we consider a manufacturer who has three options for collecting such products: (a) she can...

This study examines effects of momentary changes in mental effort on cardiovascular and eye activity measures. A total of 19 male pilots performed an instrument flight task. Task load was manipulated by having the pilots perform flight manoeuvres of varying complexity. Multilevel analyses demonstrated clear effects of momentary changes in mental effort on both the cardiovascular and the eye act...

This study examines effects of momentary changes in mental effort on cardiovascular and eye activity measures. A total of 19 male pilots performed an instrument flight task. Task load was manipulated by having the pilots perform flight manoeuvres of varying complexity. Multilevel analyses demonstrated clear effects of momentary changes in mental effort on both the cardiovascular and the eye act...

The aim of this study was to assess dual-task performance in TBI patients, under different experimental conditions, with or without explicit emphasis on one of two tasks. Results were compared with measurement of the subjective mental effort required to perform each task. Forty-three severe TBI patients at the subacute or chronic phase performed two tasks under single- and dual-task conditions:...

This research investigates how people’s perceptions of information retrieval (IR) systems, their perceptions of search tasks, and their perceptions of self-efficacy influence the amount of invested mental effort (AIME) they put into using two different IR systems: a Web search engine and a library system. It also explores the impact of mental effort on an end user’s search experience. To assess...

Networked games are susceptible to delays which degrade the playing experience. A version of Pong was developed to test how delay and delay visualization affect gamers’ mental effort, enjoyment and task performance. A predictor display shadowing the paddle was contrasted experimentally to no visualization at two levels of delay. The experiment showed that higher levels of delay increase the men...

In the present article, we explore whether people's mental representation of progress level can function as a self-regulation mechanism that helps motivate continued effort in the pursuit. We propose that when individuals have just started pursuing a goal and have accumulated only limited progress, they exaggerate the achieved progress level in their mental representation to signal a higher cha...

This paper examines a dual-task method for the assessment of mental effort during online searching, having the users engage in two tasks simultaneously. Searching was assigned as a primary task and a visual observation was set up as a secondary task. The study participants were asked to perform two searches, one on the Web and the other in a webbased library system. Perceived search difficulty ...