Is a ‘Complex’ Task Really Complex? Validating the Assumption of Cognitive Task Complexity

Abstract

In research on task‐based learning and teaching, it has traditionally been assumed that differing degrees of cognitive task complexity can be inferred through task design and/or observations of differing qualities in linguistic production elicited by second language (L2) communication tasks. Without validating this assumption, however, it is unclear at best whether the designed or inferred difference in complexity, the key independent variable, is realized as intended. Accordingly, this study adopted diverse methods from cognitive psychology for independently measuring cognitive task complexity, including: dual‐task methodology, time estimation, and self‐rating. Fifty‐three English‐L2 speakers in Japan, representing distinct proficiency levels, narrated 4 picture sequences, each containing differing numbers of characters. While performing the primary story‐telling task, participants simultaneously completed a secondary task of reacting to a color change. After each story‐telling, they also estimated their time‐on‐task and rated their perceptions of task difficulty and mental effort. Results revealed that only large differences in the task design feature (i.e., number of elements) were detectable in terms of independent measures of cognitive complexity. This finding underscores the importance of validating the assumptions about the relationship between task design and its putative effects on cognitive complexity. Findings also indicated a potential interaction among proficiency, task designs, and measures of cognitive load.

‘One Task Fits All’? The Roles of Task Complexity, Modality, and Working Memory Capacity in L2 Performance

“…Results from the Perceived Complexity Questionnaire revealed that both native speakers and L2 learners perceived more complex tasks as being significantly more complex (i.e., requiring more mental effort) than less complex tasks. These results offer additional evidence supporting the adequacy of subjective complexity self-ratings as valid measures of cognitive task demands (Révész et al, 2015;Sasayama, 2016). The present study also found differences between natives' and nonnatives' complexity ratings for less complex tasks, which support the claim that factors related to L2 proficiency and/or processing capacity may interact with perceptions of task demands (Bachman, 2002).…”

“…5 Distributions for the questionnaire data were found to be normal across groups, with no severe skewness or kurtosis. 6 The present study also collected retrospective timeon-task estimations (Baralt, 2013;Sasayama, 2016) as a supplementary measure of cognitive load, but data were not entered into the final analysis due to low reliability: Although participants were not informed beforehand that they would have to estimate task time, it is very probable that they expected to do so in the second task. As a result, participants might have estimated time retrospectively for the first task but prospectively for the second task.…”

“…A third possible explanation for these varied findings is that in most studies the difference in task complexity between tasks was not assessed (for exceptions, see Michel, ; Révész, ; Robinson, ). As has been argued in the literature (e.g., Révész, ; Sasayama, ), in order to evaluate the role of task complexity, it seems crucial to obtain independent measures of task‐generated cognitive costs, that is, to establish whether the complex version of the task posed greater cognitive demands. To date, the most common method to achieve this has been to employ self‐rated questionnaires of perceived task complexity (see Révész, Michel, & Gilabert, ; Sasayama, , for descriptions and validations of other methods).…”

L2 Learners’ and Professionals’ Perceptions of Cognitive Task Complexity : Towards Developing an Index of Task Difficulty

“…According to Sasayama (2016), TD is largely associated with "the actual effort engaged in by the individual as opposed to the supposed demand imposed by a task" (p. 232). This suggests a possible interaction between the learner's mental effort needed during their performance and the manipulation of task design.…”

“…While TC can be defined as "the cognitive load of a second language (L2) communication task" (Sasayama, 2016, p. 231) imposed on learners, TD is seen as the extent to which a task is perceived difficult based on learners' individual factors (Robinson, 2015). Research on perceptions of TD (e.g., Ishikawa, 2011;Révész & Gurzynski-Weiss, 2016;Robinson, 2001;Robinson, 2007;Sasayama, 2016;Tavakoli, 2009a;Tavakoli, 2009b;Tavakoli & Skehan, 2005) has focused on exploring the impact of different task characteristics and conditions on learners' and/or teachers' perceptions of TD. This line of research has been motivated by two TC models: Skehan's (1998Skehan's ( , 2015 Limited Attentional Capacity Model and Robinson's (2007Robinson's ( , 2015 Cognition Hypothesis.…”