Effects of Cognitive Appraisal and Mental Workload Factors on Performance in an Arithmetic Task

Abstract

We showed in a previous study an additive interaction between intrinsic and extraneous cognitive loads and of participants' alertness in an 1-back working memory task. The interaction between intrinsic and extraneous cognitive loads was only observed when participants' alertness was low (i.e. in the morning). As alertness is known to reflect an individual's general functional state, we suggested that the working memory capacity available for germane cognitive load depends on a participant's functional state, in addition to intrinsic and extraneous loads induced by the task and task conditions. The relationships between the different load types and their assessment by specific load measures gave rise to a modified cognitive load model. The aim of the present study was to complete the model by determining to what extent and at what processing level an individual's characteristics intervene in order to implement efficient strategies in a working memory task. Therefore, the study explored participants' cognitive appraisal of the situation in addition to the load factors considered previously-task difficulty, time pressure and alertness. Each participant performed a mental arithmetic task in four different cognitive load conditions (crossover of two task difficulty conditions and of two time pressure conditions), both while their alertness was low (9 a.m.) and high (4 p.m.). Results confirmed an additive effect of task difficulty and time pressure, previously reported in the 1-back memory task, thereby lending further support to the modified cognitive load model. Further, in the high intrinsic and extraneous load condition, performance was reduced on the morning session (i.e. when alertness was low) on one hand, and in those participants' having a threat appraisal of the situation on the other hand. When these factors were included into the analysis, a performance drop occurred in the morning irrespective of cognitive appraisal, and with threat appraisal in the afternoon (i.e. high alertness). Taken together, these findings indicate that mental overload can be the result of a combination of subject-related characteristics, including alertness and cognitive appraisal, in addition to well-documented task-related components (intrinsic and extraneous load). As the factors investigated in the study are known to be critically involved in a number of real job-activities, the findings suggest that solutions designed to reduce incidents and accidents at work should consider the situation from a global perspective, including individual characteristics, task parameters, and work organization, rather than dealing with each factor separately.

Measuring mental workload with the NASA-TLX needs to examine each dimension rather than relying on the global score: an example with driving

“…Cognitive load theory has been tested on many occasions in the fields of educational psychology and the psychology of learning (for a review, see Chanquoy, Tricot, and Sweller 2007). In recent years, it has at long last been applied to the field of ergonomics (Debué and van de Leemput 2014; Galy et al 2012;Galy and Mélan 2015;Mélan and Cascino 2014),…”

“…Some aspects of mental workload therefore depend on features of the task. In previous studies (Debué and van de Leemput, 2014;Galy et al 2012;Galy and Mélan 2015), parallels were drawn with Sweller (1988)'s intrinsic load, which is directly dependent upon task demand, and extraneous load, which is determined by the context in which this task is performed.…”

“…It is possibly that this category of mental workload is even more reliant on the availability of cognitive resources than the two others on which it therefore depends. For instance, a specific task performed in a given context necessarily generates a degree of intrinsic and extraneous load, so if the task is difficult and the context unfavourable, these two types of load will be very high, draining cognitive resources and leaving very little left for germane load Galy and Mélan 2015;Young, Watcher, Cate, O'Sullivan, and Irby, 2016). Even if intrinsic and extraneous loads do not use up all the resources, the remainder is not necessarily allocated to germane load.…”

“…Previous researches (Galy, Cariou, and Mélan 2012;Galy and Mélan 2015) had shown that performance on tasks such as mental arithmetic or memorization can only be explained if mental workload is broken down into several different categories. In these studies, the authors controlled the participants' level of alertness and/or cognitive appraisal of the task, and manipulated task difficulty and time pressure.…”

“…A further factor that has a major effect on germane load is the level of activation, as the individual's activation state is thought to determine the amount of available resources Galy and Mélan 2015). According to Thayer (1986)'s model of multidimensional activation, arousal is the product of two separate but interconnected processes, namely alertness and tension.…”