The impact of pain on subsequent effort and cognitive performance

Theoretical accounts of pain and empirical evidence indicate that pain and cognitive control share common neurocognitive processes. Numerous studies have examined the interactions between pain and cognitive performance when they occur simultaneously, typically showing analgesic effects of task performance and impaired performance due to pain. However, the sequential impact of pain on cognitive control and effort remains less clear. This study investigated the influence of a first task including painful vs. non-painful thermal stimuli on effort-related cardiac response and performance in a subsequent moderately difficult cognitive task. Drawing on the hypothesis that experiencing pain should recruit cognitive resources and reduce perceived ability, we predicted lower task performance and/or stronger compensatory effort in the subsequent cognitive task after the painful than after the non-painful first task. Results support our predictions regarding the effect of pain on subsequent cognitive performance, which was moderately lower after the painful task. However, such a decrease in task proficiency was not associated with a comparable decrease in perceived capacity or increase in effort-related cardiac reactivity. Nevertheless, further correlational analyses indicated that effort mobilization and perceived capacity were significantly related to pain ratings. Moderate pain was associated with stronger effort during the cognitive task whereas high pain led to disengagement, i.e., a low effort. Moreover, in line with our predictions, higher pain ratings were associated with lower self-reported capacity to perform the cognitive task. We discuss these findings regarding the relationship between effort and performance; the impact of fatigue on motivation; and interindividual variability in these after-effects.