Subjective cognitive effort: a model of states, traits, and time.

Self-regulation theories were used to develop a dynamic model of the determinants of subjective cognitive effort. The authors assessed the roles of malleable states and stable individual differences. Subjective cognitive effort and perceived difficulty were measured while individuals performed an air traffic control task. As expected, Conscientiousness moderated the effort trajectory. Individuals with high Conscientiousness maintained subjective cognitive effort at high levels for longer than their counterparts. There were also individual differences in reactions to perceptions of task difficulty. The intra-individual relationship between perceived difficulty and subjective cognitive effort was stronger for individuals with low ability or low Conscientiousness than for their counterparts. A follow-up study showed that the measures of perceived difficulty and subjective cognitive effort were sensitive to a task difficulty manipulation as well as that the relationship between perceived difficulty and subjective cognitive effort held after controlling for self-set goal level. These findings contribute to the self-regulation literature by identifying factors that influence changes in subjective cognitive effort during skill acquisition.