Mental Effort

Purpose-The purpose of this study is to investigate the effectiveness of diagrammatic visualisation techniques versus sentential learning contexts in an accounting subject using the theoretical lens of cognitive load theory (CLT). Design/methodology/approach-The present study used four groups of students; two groups completed a task using diagrammatic visualisation learning materials, with one of the groups undertaking their leaning activities collaboratively and another on an individual basis, whereas two comparison groups were given a sentential learning context without diagrams, with one group undertaking their leaning activities collaboratively and the other individually. In addition to performance grades, cognitive load selfreport scores were also elicited from participants. Findings-The findings of this study indicate support for diagrammatic visualisation techniques for students working collaboratively. Compared with sentential learners, the authors find significantly improved test performance for students who work collaboratively in a diagrammatic visualisation environment. Students in the visualisation environments obtained higher grades than those in the sentential group. In terms of mental effort, students in the visualisation conditions reported the lowest cognitive load. Practical implications-The authors conclude that diagrammatic visualisation learning techniques enhance student performance outcomes, particularly for those who work collaboratively. CLT assists in the understanding of the mental processes involved in learning. Instructional designers need to consider CLT when developing diagrammatic visualisation material to enable students to obtain the best possible learning outcomes. Originality/value-This study addresses a gap in the literature by examining the use of diagrammatic visualisation materials as an alternative to text when learning accounting. The study explores the effect of visualisation material on students' cognitive load by analysing their mental effort. The study contributes useful findings on visualisation as a conduit to enhancing the understanding of accounting using CLT principles.

In our anxiogenic and stressful world, the maintenance of an optimal cognitive performance is a constant challenge. It is particularly true in complex working environments (e.g. flight deck, air traffic control tower), where individuals have sometimes to cope with a high mental workload and stressful situations. Several models (i.e. processing efficiency theory, cognitive-energetical framework) have attempted to provide a conceptual basis on how human performance is modulated by high workload and stress/anxiety. These models predict that stress can reduce human cognitive efficiency, even in the absence of a visible impact on the task performance. Performance may be protected under stress thanks to compensatory effort, but only at the expense of a cognitive cost. Yet, the psychophysiological cost of this regulation remains unclear. We designed two experiments involving pupil diameter, cardiovascular and prefrontal oxygenation measurements. Participants performed the Toulouse N-back Task that intensively engaged both working memory and mental calculation processes under the threat (or not) of unpredictable aver-sive sounds. The results revealed that higher task difficulty (higher n level) degraded the performance and induced an increased tonic pupil diameter, heart rate and activity in the lateral prefrontal cortex, and a decreased phasic pupil response and heart rate variability. Importantly, the condition of stress did not impact the performance, but at the expense of a psychophysiological cost as demonstrated by lower phasic pupil response, and greater heart rate and prefrontal activity. Prefrontal cortex seems to be a central region for mitigating the influence of stress because it subserves crucial functions (e.g. inhibition, working memory) that can promote the engagement of coping strategies. Overall, findings confirmed the psychophysiological cost of both mental effort and stress. Stress likely triggered increased motivation and the recruitment of additional cognitive resources that minimize its aversive effects on task performance (effectiveness), but these compensatory efforts consumed resources that caused a loss of cognitive efficiency (ratio between performance effectiveness and mental effort).

In Learning and Instruction, 27, 50-62.  Argument-counterargument integration (Nussbaum, 2008) refers to the process of evaluating, refuting, and synthesizing arguments on two sides of an issue when creating justification for an overall conclusion. This study compared the cognitive load of two critical thinking strategies related to argument-counterargument integration:  (a) constructing design claims that minimize disadvantages of an alternative, and (b) weighing refutations (which weaken an argument by arguing that there are more important values at stake).  College students (N = 285) first completed the Need for Cognition (NFC) scale and were then presented with materials summarizing arguments and counterarguments on the topic of grading class participation.  Participants completed a small, integrative essay justifying a stand on the issue, and completed the Mental Effort Rating Scale (Paas, 1992).  Participants who generated complex weighing refutations reported more mental effort than those constructing complex design claims (and the control group), with a stronger relationship with those high in NFC.  The need to coordinate disparate elements in working memory may explain the higher load associated with constructing weighing refutations.  Students may need more (and different types of) scaffolding in using this strategy than when constructing a design claim, which is a more sequential process.