How Do Children Deal With Conflict? A Developmental Study of Sequential Conflict Modulation

Contextual adaptation of cognitive flexibility in kindergartners and fourth graders

This study investigated the development of children's ability to find the optimal balance between flexibility and stability as a function of the frequency of required task switches. This question was addressed in two situations contrasting the dynamics of engagement of reconfiguration processes (reactive vs. proactive). A cued task-switching paradigm was presented to kindergartners and fourth graders, who are known to differ in their preferential mode of control engagement. Flexibility adaptation was examined through the modulation of switching costs by switch proportion, the so-called list-wide switch proportion (LWSP) effect. When the situation forced the use of reactive control (Experiment 1: simultaneous presentation of the cue and the stimulus), we found the LWSP effect with a greater magnitude in kindergartners than in fourth graders. In the situation inducing proactive control (Experiment 2: task cue presented before and until the stimulus), flexibility adaptation was obtained when error rates were considered but not response times. By demonstrating that even young children are capable of flexibility adaptation to contextual demands, these findings support the hypothesis that implicitly triggered adaptation of control may develop as early as the end of the preschool years despite the immaturity of cognitive control during this period.

Developmental changes in impulse control: Trial-by-trial EMG dissociates the evolution of impulse strength from its subsequent suppression

Goal-oriented behavior can be disrupted by irrelevant information that automatically activates incorrect responses. While behavioral errors reveal response capture in such situations, they are only the tip of the iceberg. Additional subliminal activations of the incorrect responses (partial errors) can be revealed on correctly responded trials thanks to electromyography (EMG). In the current study, for the first time, EMG recorded in children was combined with distributional analyses. This allowed to investigate the properties of incorrect response activations and to highlight developmental changes in impulse control. A sample of 114 children aged 6-14 years was studied. Children performed a Simon task in which the irrelevant stimulus-position automatically activates a response that might be compatible or incompatible with the correct one. On incompatible trials, the automatic response activation must be overcome by controlled response selection. As previously observed in adults, our approach revealed the presence of an automatic EMG activation of the incorrect response elicited by the irrelevant stimulus dimension. Further, it revealed another independent source at the origin of incorrect response activations: the tendency to guess for response alternation. Both sources increased the frequency of early incorrect EMG activations, indicating impulsive responding. In addition, the influence of both sources decreased with increasing age. Thus, development is marked by improved ability to manage distractibility on the one hand and decreased tendency to rely on a guessing strategy on the other.

Preschoolers are capable of fine-grained implicit cognitive control: Evidence from development of the context-specific proportion congruency effect

Whereas much of the developmental literature has focused on the difficulties of young children in regulating their behavior, an increasing base of evidence suggests that children may be capable of surprisingly flexible engagement of cognitive control when based on implicit experience with the situation. One of the most fine-grained examples of implicit cognitive control in adults is the context-specific proportion congruency (CSPC) effect-the finding that interference in a conflict task is reduced for stimuli that are presented in a context (e.g., a spatial location) where stimuli are generally incongruent. Can such a subtle modulation of control be observed in children? In Experiment 1 (N = 180), we showed that this effect exists in preschoolers for two different types of context manipulation and that its magnitude is at least as large as in older children. In Experiment 2 (N = 40), we confirmed that the effect transfers to unbiased stimuli, indicating that it is not attributable to contingency learning of stimulus-response associations and can be taken to actually reflect cognitive control. These results support the possibility that implicit cognitive control (implemented without explicit intentions and without requiring subject awareness) can be functionally distinct from explicit control and that even very young children can implement fine-grained cognitive control when it is based on implicit cues.

Dynamic Adjustments of Midfrontal Control Signals in Adults and Adolescents

During task performance, our level of cognitive control is dynamically adjusted to task demands as reflected, for example, by the congruency sequence effect (CSE) in conflict tasks. Although brain areas related to cognitive control show protracted maturation across adolescence, previous studies found that adolescents show similar behavioral CSEs to adults. In the present study, we investigated whether there are age-related changes in the neural underpinnings of dynamic control adjustments using electroencephalography. Early adolescents (ages 12-14, N = 30) and young adults (ages 25-27, N = 29) completed a confound-minimized flanker task optimized for the detection of sequential control adjustments. The CSE was observed in midfrontal theta power thought to capture anterior cingulate cortex-mediated monitoring processes but was not modulated significantly by age. Adolescents, however, showed a smaller congruency effect in the power and cross-trial temporal consistency of midfrontal theta oscillations than adults. No age differences were observed in phase-based connectivity between midfrontal and lateral frontal regions in the theta band. These findings provide strong support for the role of midfrontal theta oscillations in conflict monitoring and reactive control and suggest that the cognitive system of early adolescents initially responds less reliably to the occurrence of conflict than that of adults.

Different temporal dynamics after conflicts and errors in children and adults

After perceiving cognitive conflicts or errors, children as well as adults adjust their performance in terms of reaction time slowing on subsequent actions, resulting in the so called post-conflict slowing and post-error slowing, respectively. The development of these phenomena has been studied separately and with different methods yielding inconsistent findings. We aimed to assess the temporal dynamics of these two slowing phenomena within a single behavioral task. To do so, 9-13-year-old children and young adults performed a Simon task in which every fifth trial was incongruent and thus induced cognitive conflict and, frequently, also errors. We compared the reaction times on four trials following a conflict or an error. Both age groups slowed down after conflicts and did so even more strongly after errors. Disproportionally high reaction times on the first post-error trial were followed by a steady flattening of the slowing. Generally, children slowed down more than adults. In addition to highlighting the phenomenal and developmental robustness of post-conflict and post-error slowing these findings strongly suggest increasingly efficient performance adjustment through fine-tuning of cognitive control in the course of development.

Attentional Reorientation and Inhibition Adjustment in a Verbal Stroop Task: A Lifespan Approach to Interference and Sequential Congruency Effect

Several parameters influence the interference effect elicited in a Stroop task, especially contextual information. Contextual effects in the Stroop paradigms are known as the Gratton or Sequential congruency effect (SCE). This research aims at isolating two processes contributing to the SCE in a Stroop paradigm, namely attentional reorientation from the color to the word and vice-versa, as well as inhibition (engagement/disengagement from one trial to the next one). To this end, in Study 1 subprocesses of the SCE were isolated. Specifically, attentional reorientation and inhibition were segregated by submitting young adults to a discrete verbal Stroop task including neutral trials. In Study 2, the same procedure was applied to 124 participants aged from 10 to 80 years old to analyze how interference, SCE, and the aforementioned decomposition of attention and inhibition change across the lifespan. In both studies, the Gratton effect was only partially replicated, while both attentional reorientation and inhibition effects were observed, supporting the idea that these two processes contribute to SCE on top of conflict monitoring and of other processes highlighted in different theories (contingency learning, feature integration, and repetition expectancy). Finally, the classical age-related evolution was replicated in Study 2 on raw interference scores, but no age effect was observed when processing speed was taken into account, nor on the isolated attentional reorientation and inhibition processes, which is in line with the hypothesis of stability of the inhibition processes over age.