Bilingual children often outperform monolingual children in tasks of cognitive control. This advantage may be a consequence of the fact that bilinguals have more practice controlling attention due to an ongoing need to manage two languages. However, existing evidence is limited because possible differences in ethnicity and socioeconomic status have not been properly controlled. To address this issue, we administered the Simon task to bilingual and monolingual children of identical ethnic and socioeconomic backgrounds. Bilingual and monolingual children performed identically, whereas children from higher SES families were advantaged relative to children from lower SES families. Controlling differences in SES and ethnicity may attenuate the bilingual advantage in cognitive control.

Children of different ages often perseverate, repeating previous behaviors when they are no longer appropriate, despite appearing to know what they should be doing. Using neural network models, we explore an account of these phenomena based on a distinction between active memory (subserved by the prefrontal cortex) and latent memory (subserved by posterior cortex). The models demonstrate how (a) perseveration occurs when an active memory of currently relevant knowledge is insufficiently strong to overcome a latent bias established by previous experience, (b) apparent dissociations between children's knowledge and action may reflect differences in the amount of conflict between active and latent memories that children need to resolve in the tasks, and (c) differences in when children master formally similar tasks (decalage) may result from differences in the strength of children's initial biases. The models help to clarify how prefrontal development may lead to advances in flexible thinking.

Children's understanding of emotion in speech was explored in three experiments. In Experiment 1, 4- to 10-year-old children and adults (N = 165) judged the happiness or sadness of the speaker from cues conveyed by propositional content and affective paralanguage. When the cues conflicted (i.e., a happy situation was described with sad paralanguage), children relied primarily on content, in contrast to adults, who relied on paralanguage. There were gradual developmental changes from 4-year-olds' almost exclusive focus on content to adults' exclusive focus on paralanguage. Children of all ages exhibited greater response latencies to utterances with conflicting cues than to those with nonconflicting cues, indicating that they processed both sources of emotional information. Children accurately labeled the affective paralanguage when the propositional cues to emotion were obscured by a foreign language (Experiment 2, N = 20) or by low-pass filtering (Experiment 3, N = 60). The findings are consistent with children's limited understanding of the communicative functions of affective paralanguage.

The transition from childhood to adulthood is marked by pronounced functional and structural brain transformations that impact cognition and behavior. Here, we use a functional imaging approach to reveal dynamic changes in coupling strength between networks and the expression of discrete brain configurations over human development during rest and a cognitive control task. Although the brain's repertoire of functional states was generally preserved across ages, state-specific temporal features, such as the frequency of expression and the amount of time spent in select states, varied by age in ways that were dependent on condition. Increasing age was associated with greater variability of connection strengths across time at rest, while there was a selective inversion of this effect in higher-order networks during implementation of cognitive control. The results suggest that development is characterized by the modification of dynamic coupling to both maximize and constrain functional variability in response to ongoing cognitive and behavioral requirements.

According to recent accounts, the processing of errors and generally infrequent, surprising (novel) events share a common neuroanatomical substrate. Direct empirical evidence for this common processing network in humans is, however, scarce. To test this hypothesis, we administered a hybrid error-monitoring/novelty-oddball task in which the frequency of novel, surprising trials was dynamically matched to the frequency of errors. Using scalp electroencephalographic recordings and event-related functional magnetic resonance imaging (fMRI), we compared neural responses to errors with neural responses to novel events. In Experiment 1, independent component analysis of scalp ERP data revealed a common neural generator implicated in the generation of both the error-related negativity (ERN) and the novelty-related frontocentral N2. In Experiment 2, this pattern was confirmed by a conjunction analysis of event-related fMRI, which showed significantly elevated BOLD activity following both types of trials in the posterior medial frontal cortex, including the anterior midcingulate cortex (aMCC), the neuronal generator of the ERN. Together, these findings provide direct evidence of a common neural system underlying the processing of errors and novel events. This appears to be at odds with prominent theories of the ERN and aMCC. In particular, the reinforcement learning theory of the ERN may need to be modified because it may not suffice as a fully integrative model of aMCC function. Whenever course and outcome of an action violates expectancies (not necessarily related to reward), the aMCC seems to be engaged in evaluating the necessity of behavioral adaptation.