The use of event‐related potentials in the study of early cognitive development

The article by Guillaume Thierry is a welcome one, alerting the field to the exciting ways in which event‐related potentials (ERPs) can be used to study cognitive development. It is also timely: there is great interest in the brain sciences, and in how neuroscience can be applied to cognitive development and indeed to education. In my view, however, the article is perhaps too cautious. It does not seem necessary to delay the use of ERPs in cognitive work until all in the field have agreed on the sound characterization of ERP components. It should be possible for further characterization to proceed hand‐in‐hand with data gathering on applied questions. In fact, as partly noted by Thierry, in the auditory domain well‐characterized ERP components are already available, even for infants (e.g. Cheour et al., 1997; Leppänen and Lyytinen, 1997). Furthermore, it is of developmental interest to study older children as well as infants. If ERPs are seen as a tool to complement existing behavioural investigations, rather than as a stand‐alone method to be used independently, then auditory ERPs can certainly be used in current cognitive‐developmental work. Copyright © 2005 John Wiley & Sons, Ltd.     

Conceptual Integration of Arithmetic Operations With Real‐World Knowledge: Evidence From Event‐Related Potentials

Research on language processing has shown that the disruption of conceptual integration gives rise to specific patterns of event‐related brain potentials (ERPs)—N400 and P600 effects. Here, we report similar ERP effects when adults performed cross‐domain conceptual integration of analogous semantic and mathematical relations. In a problem‐solving task, when participants generated labeled answers to semantically aligned and misaligned arithmetic problems (e.g., 6 roses + 2 tulips  = ? vs. 6 roses + 2 vases  = ?), the second object label in misaligned problems yielded an N400 effect for addition (but not division) problems. In a verification task, when participants judged arithmetically correct but semantically misaligned problem sentences to be “unacceptable,” the second object label in misaligned sentences elicited a P600 effect. Thus, depending on task constraints, misaligned problems can show either of two ERP signatures of conceptual disruption. These results show that well‐educated adults can integrate mathematical and semantic relations on the rapid timescale of within‐domain ERP effects by a process akin to analogical mapping.     

Age‐related changes in the control of episodic retrieval: an ERP study of recognition memory in children and adults

We examined developmental aspects of the ability to monitor the temporal context of an item’s previous occurrence while event‐related potentials (ERPs) were recorded. In a continuous recognition task, children between 10 and 12 years and young adults watched a stream of pictures repeated with a lag of 10–15 intervening items and indicated recurrences. In a second run, these already familiar pictures were repeated as non‐targets along with new pictures, while subjects were instructed to indicate only recurrences within the run. Young adults were able to maintain high performance levels in both tasks, whereas children had longer response times and committed a large number of false alarms to non‐targets. ERPs in both age groups showed similar parietal old/new effects for target repetitions within runs. In addition, adults’ ERPs showed similar old/new effects at frontal electrodes for repetitions and non‐targets, presumably reflecting assessments of familiarity, whereas for children repeated relative to first presentations were associated with more negative‐going waveforms at anterior frontal recording sites. Together, these results suggest a continuing maturation of the brain networks assessing novelty or familiarity. Recollection as indexed by parietal old/new effects appeared similar between young adults and children, but the development of controlled episodic retrieval, resulting in recollection of non‐target information, appears to continue well into adolescence.     

Cortical correlates of impaired self-regulation in personality disordered patients with traits of psychopathy

Psychopathic personality disordered patients would, by virtue of a failure to self-regulate, be expected to show diminished amplitudes of feedback-related brain potentials. Among a sample of personality disordered patients detained at different levels of security, those who met a Psychopathy Checklist (PCL) criterion of 25 or above were identified (N = 27). Their event-related brain potentials (ERPs), together with those of their nonpsychopathic counterparts (N = 22) and healthy male controls (N = 20), were measured while they performed a visual Go/No Go task, with feedback given for correct and incorrect performance. Psychopathic patients showed a significantly reduced amplitude of an early frontal negative ERP component maximally evoked by negative feedback, and a high rate of errors of commission. Findings are consistent with the idea that psychopathic patients' unsuccessful attempts to self-regulate reflect a cognitive deficit characterised by a failure to attend and respond to a mismatch between expected and obtained outcomes.     

Atypical brain responses to sounds in children with specific language and reading impairments

This study tested if children with specific language impairment (SLI) or children with specific reading disability (SRD) have abnormal brain responses to sounds. We tested 6‐ to 12‐year‐old children with SLI (N =19), children with SRD (N =55), and age‐matched controls (N =36) for their passive auditory event‐related potentials (ERPs) to tones, rapid tones, vowels and consonant‐vowels. Thirty‐eight percent of the children with SLI or SRD had less typical passive auditory ERPs in the N1–P2 window to sounds in general, rather than to tones, rapid tones, vowels or consonant‐vowels specifically. The ERPs of these children were significantly ‘flatter’ in the N1–P2 region than normal. All the children with flatter ERPs in the N1–P2 region had poor non‐word reading. A subgroup of these poor non‐word readers also had poor non‐word repetition. These findings support the hypothesis that impaired auditory processing is a causal risk factor for both SLI and SRD.     

Previous reward decreases errors of commission on later ‘No‐Go’ trials in children 4 to 12 years of age: evidence for a context monitoring account

Inhibitory control is widely hypothesized to be the cornerstone of executive function in childhood and the central deficit in a number of developmental disorders, including attention‐deficit/hyperactivity disorder (ADHD). However, recent evidence from adults indicates that performance on response inhibition tasks may primarily reflect non‐inhibitory attentional control (context monitoring) processes. Yet it may be that inhibition plays a more central role in childhood – a time when the architecture of cognitive processes might be more transparent due to wide variability in skill level. Here we directly test inhibitory and context monitoring explanations of task performance on a Go/No‐Go task in a large group of children 4–12 years of age. We conclude that traditional inhibitory conceptualizations of task performance on the Go/No‐Go task cannot account for our findings, calling into question evidence supporting a central role for inhibitory control in cognitive development or developmental psychopathology.     

Developmental changes in memory encoding: insights from event‐related potentials

The aim of the present study was to investigate developmental changes in encoding processes between 6‐year‐old children and adults using event‐related potentials (ERPs). Although episodic memory (‘EM’) effects have been reported in both children and adults at retrieval and subsequent memory effects have been established in adults, no previous ERP studies have examined subsequent memory effects in children. This represents a critical gap in the literature because encoding processes, and changes in neural correlates supporting encoding, partially account for age‐related improvements in children's memory performance. Results revealed that subsequent memory effects differed between children and adults temporally, directionally, and topographically. These findings lend support to the hypothesis that encoding processes and their neural correlates are an important source of change in memory development. A video abstract of this article can be viewed at http://youtu.be/sH83_qVimgc .     

The sustained effect of emotional signals on neural processing in 12‐month‐olds

Around the end of the first year of life, infants develop a social referencing ability – using emotional information from others to guide their own behavior. Much research on social referencing has focused on changes in behavior in response to emotional information. The present study was an investigation of the changes in neural responses that underlie social referencing behavior, reflected in event‐related potentials (ERPs). Twenty‐six 12‐month‐olds participated in a single‐session visit in which ERPs were recorded both immediately before and after a behavioral intervention in which infants' caregivers provided positive, negative or neutral information about each of three stimuli (ERP data available for n = 17). After the intervention, infants devoted more neural resources to processing negative versus neutral and positive information, as observed in early and late positive‐going components. Changes in neural responses from the pre‐ to post‐intervention recordings clarify this observation, indicating a sustained response in the negative and positive conditions, and a decrease in the neutral condition, suggesting an attenuation effect in the neutral condition. Further, infants who attended most to the objects in the behavioral intervention showed increased neural responses in the negative condition and decreased responses in the positive condition. Taken together, these findings suggest that infants' neural responses are differentially affected by positive, negative and neutral information. Furthermore, the findings highlight the importance of measuring the change in neural responses to better interpret post‐experience responses.     

Reductions of intimate partner violence resulting from supplementing children with omega‐3 fatty acids: A randomized,double‐blind,placebo‐controlled,stratified, parallel‐group trial

Omega‐3 supplementation has been found to reduce externalizing behavior in children. Reciprocal models of parent‐child behavior suggest that improving child behavior could lead to improvements in parent behavior, however no study has examined whether omega‐3 supplementation in children could reduce intimate partner violence or child maltreatment by their adult caregivers. In this randomized, double‐blind, placebo‐controlled, stratified, parallel group trial, a community sample of children were randomized to receive either a fruit drink containing 1 gm of omega‐3 fats (Smartfish Recharge; Omega‐3 group, n = 100) or the same fruit drink without omega‐3's (Placebo group, n = 100). Child participants, adult caregivers, and research staff were blinded to group assignment. Adult caregivers reported inter‐partner and child‐directed physical assault and psychological aggression at baseline, 6 months (end of treatment) and 12 months (6 months post‐treatment) using the Conflicts Tactics Scale. Caregivers of children in the omega‐3 group reported long‐term reductions in psychological aggression in a group × time interaction. Improvements in adult psychological aggression were correlated with improvements in child externalizing behavior scores. No differences were reported for child maltreatment. This study is the first to show that omega‐3 supplementation in children can reduce inter‐partner psychological aggression among adult caregivers not receiving supplements. Findings suggest that improving child behavior through omega‐3 supplementation could have long‐term benefits to the family system as a whole.

     

The neural correlates of processing newborn and adult faces in 3‐year‐old children

The current study examines the processing of upright and inverted faces in 3‐year‐old children (n = 35). Event‐related potentials (ERPs) were recorded during a passive looking paradigm including adult and newborn face stimuli. We observed three face‐sensitive components, the P1, the N170 and the P400. Inverted faces elicited shorter P1 latency and larger P400 amplitude. P1 and N170 amplitudes were larger for adult faces. To examine the role of experience in the development of face processing, the processing of adult and newborn faces was compared for children with a younger sibling (n = 23) and children without a younger sibling (n = 12). Age of sibling at test correlated negatively with P1 amplitude for adult and newborn faces. This may indicate more efficient processing of different face ages in children with a younger sibling and potentially reflects a more flexible face representation.     

Brain and behavioral inhibitory control of kindergartners facing negative emotions

Inhibitory control (IC) – one of the most critical functions underlying a child's ability to self‐regulate – develops significantly throughout the kindergarten years. Experiencing negative emotions imposes challenges on executive functioning and may specifically affect IC. In this study, we examined kindergartners' IC and its related brain activity during a negative emotional situation: 58 children (aged 5.5–6.5 years) performed an emotion‐induction Go/NoGo task. During this task, we recorded children's performance and brain activity, focusing on the fronto‐central N2 component in the event‐related potential (ERP) and the power of its underlying theta frequency. Compared to Go trials, inhibition of NoGo trials was associated with larger N2 amplitudes and theta power. The negative emotional experience resulted in better IC performance and, at the brain level, in larger theta power. Source localization of this effect showed that the brain activity related to IC during the negative emotional experience was principally generated in the posterior frontal regions. Furthermore, the band power measure was found to be a more sensitive index for children's inhibitory processes than N2 amplitudes. This is the first study to focus on kindergartners' IC while manipulating their emotional experience to induce negative emotions. Our findings suggest that a kindergartner's experience of negative emotion can result in improved IC and increases in associated aspects of brain activity. Our results also suggest the utility of time‐frequency analyses in the study of brain processes associated with response inhibition in young children.     

Preschool children’s interpretation of object‐initial sentences: Neural correlates of their behavioral performance

The acquisition of the function of case‐marking is a key step in the development of sentence processing for German‐speaking children since case‐marking reveals the relations between sentential arguments. In this study, we investigated the development of the processing of case‐marking and argument structures in children at 3, 4;6 and 6 years of age, as well as its processing in adults. Using EEG, we measured event‐related potentials (ERPs) in response to object‐initial compared to subject‐initial German sentences including transitive verbs and case‐marked noun phrases referring to animate arguments. We also tested children’s behavioral competence in a sentence‐picture matching task. Word order and case‐marking were manipulated in German main clauses. Adults’ behavioral performance was close to perfect and their ERPs revealed a negativity for the processing of the topicalized accusative marked noun phrase (NP1) and no effect for the second NP (NP2) in the object‐initial structure. Children’s behavioral data showed a significant above‐chance outcome in the subject‐initial condition for all age groups, but not for the object‐initial condition. In contrast to adults, the ERPs of 3‐year‐olds showed a positivity at NP1, indicating difficulties in processing the non‐canonical object‐initial structures. Children at the age of 4;6 did not differ in the processing patterns of object‐initial vs. subject‐initial sentences at NP1 but showed a slight positivity at NP2. This positivity at NP2, which implies syntactic integration difficulties, is more pronounced in 6‐year‐olds but is absent in adults. At NP1, however, 6‐year‐olds show the same negativity as adults. In sum, the behavioral and electrophysiological findings demonstrate that children in each age group use different strategies, which are indicative of their developmental stage. While 3‐year‐olds merely detect differences in the two sentence structures without being able to use this information for sentence comprehension, 4;6‐year‐olds proceed to use mainly a word‐order strategy, processing NP1 in both conditions in the same manner, which leads to processing difficulties upon detecting case‐marking cues at NP2. At the age of 6, children are able to use case‐marking cues for comprehension but still show enhanced effort for correct thematic‐role assignment.     

ERPs and behavioral inhibition in a Go/No-go task in children with attention-deficit hyperactivity disorder

In order to study the behavioral responses and the brain inhibition process in children with attention-deficit hyperactivity disorder (ADHD), Event-Related Potentials (ERPs) were recorded from 30 scalp electrodes in 21 ADHD and 21 normal boys during performing a Go/No-go task. ADHD children made fewer correct responses to both Go and No-go stimuli than normal controls. The frontal N2 amplitude was larger for No-go stimuli than Go stimuli in both groups, reflecting inhibition of responding. Smaller N2 amplitudes to No-go stimuli were found in ADHD children, but only when the Go/No-go task was performed after a first stimulus-response compatibility (SRC) task. In addition, the controls exhibited a prolonged N2 only when the Go/No-go task was performed second. However, the ADHD subjects exhibited this prolonged N2 when the task was first, but not when it was second. These results suggest an inhibitory regulation problem rather an inhibition deficit in ADHD children.     

Implications of ongoing neural development for the measurement of the error‐related negativity in childhood

Event‐related potentials (ERPs) have been proposed as biomarkers capable of reflecting individual differences in neural processing not necessarily detectable at the behavioral level. However, the role of ERPs in developmental research could be hampered by current methodological approaches to quantification. ERPs are extracted as an average waveform over many trials; however, actual amplitudes would be misrepresented by an average if there was high trial‐to‐trial variability in signal latency. Low signal temporal consistency is thought to be a characteristic of immature neural systems, although consistency is not routinely measured in ERP research. The present study examined the differential contributions of signal strength and temporal consistency across trials in the error‐related negativity (ERN) in 6‐year‐old children, as well as the developmental changes that occur in these measures. The 234 children were assessed annually in kindergarten, 1st, and 2nd grade. At all assessments signal strength and temporal consistency were highly correlated with the average ERN amplitude, and were not correlated with each other. Consistent with previous findings, ERN deflections in the averaged waveform increased with age. This was found to be a function of developmental increases in signal temporal consistency, whereas signal strength showed a significant decline across this time period. In addition, average ERN amplitudes showed low‐to‐moderate stability across the three assessments whereas signal strength was highly stable. In contrast, signal temporal consistency did not evidence rank‐order stability across these ages. Signal strength appears to reflect a stable individual trait whereas developmental changes in temporal consistency may be experientially influenced.     

Comparing Self-Regulation-Associated Event Related Potentials in Preschool Children with and without High Levels of Disruptive Behavior

Deficient self-regulation plays a key role in the etiology of early onset disruptive behavior disorders and signals risk for chronic psychopathology. However, to date, there has been no research comparing preschool children with and without high levels of disruptive behavior using Event Related Potentials (ERPs) associated with specific self-regulation sub-processes. We examined 15 preschool children with high levels of disruptive behavior (35 % female) and 20 peers with low disruptive behavior (50 % female) who completed a Go/No-go task that provided emotionally valenced feedback. We tested whether 4 ERP components: the Error Related Negativity, the Error Positivity, the Feedback Related Negativity, and the No-go N2, differed in preschool children with and without high levels of disruptive behavior. Preschoolers with high levels of disruptive behavior showed less differentiation between the Error Positivity and corresponding waveforms following correct responses at posterior sites. Preschoolers with high and low disruptive behavior also showed differences in Go/No-go N2 waveform amplitudes across electrodes. These findings suggest that preschool children with high levels of disruptive behavior may show abnormal brain activity during certain self-regulation sub-processes, informing potential advances in conceptualizing and treating early disruptive behavior.     

Children prenatally exposed to maternal anxiety devote more attentional resources to neutral pictures

Maternal anxiety during pregnancy can negatively affect fetal neurodevelopment, predisposing the offspring to a higher risk of behavioral and emotional problems later in life. The current study investigates the association between maternal anxiety during pregnancy and child affective picture processing using event‐related brain potentials (ERPs). Mothers reported anxiety during the second trimester using the anxiety subscale of the Symptom Checklist (SCL‐90). At age 4 years, child affective picture processing (N = 86) was measured by recording ERPs during viewing of neutral, pleasant, and unpleasant pictures selected from the International Affective Pictures System. The late positive potential (LPP)—an ERP component reflecting individual differences in affective processing—was used as child outcome. The expected positive association between maternal anxiety and LPP amplitude for unpleasant pictures was not found. Nevertheless, we found a positive association between maternal anxiety during pregnancy and LPP amplitudes for neutral pictures in the middle and late time window at anterior locations (all p < .05). These associations remained significant after adjusting for maternal postnatal anxiety and gestational age at birth and after FDR correction for multiple comparisons. Our study provides neurophysiological evidence that children prenatally exposed to higher maternal anxiety devote more attentional resources to neutral pictures, but not to unpleasant pictures. Possibly, these children show enhanced vigilance for threat when viewing neutral pictures. Although useful in dangerous environments, this enhanced vigilance may predispose children prenatally exposed to higher maternal anxiety to developing behavioral and/or emotional problems later in life. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=kEzYi6IS2HA     

Trait BIS predicts alpha asymmetry and P300 in a Go/No‐Go task

Inspired by the revised Behavioural Inhibition System (BIS) theory the present study probed the association between individual differences in Trait BIS and electroencephalogram indicators of conflict processing/inhibition. Sixty‐nine male participants either high or low in Trait BIS completed a Go/No‐Go task while the electroencephalogram was recorded. As expected, Trait BIS was associated with the No‐Go‐anteriorisation of the P300 event‐related potential (i.e. an index of response inhibition presumably generated in the dorsal anterior cingulate—an area implicated in conflict processing) and with No‐ Go‐related changes towards left frontal alpha activity (i.e. presumably more activity in right prefrontal cortex—an area implicated in response inhibition). These findings support the role of conflict processing attributed to BIS functioning in the revised theory. Copyright © 2009 John Wiley & Sons, Ltd.     

Brain bases of morphological processing in Chinese‐English bilingual children

Can bilingual exposure impact children's neural circuitry for learning to read? To answer this question, we investigated the brain bases of morphological awareness, one of the key spoken language abilities for learning to read in English and Chinese. Bilingual Chinese‐English and monolingual English children (N = 22, ages 7–12) completed morphological tasks that best characterize each of their languages: compound morphology in Chinese (e.g. basket + ball = basketball) and derivational morphology in English (e.g. re + do = redo). In contrast to monolinguals, bilinguals showed greater activation in the left middle temporal region, suggesting that bilingual exposure to Chinese impacts the functionality of brain regions supporting semantic abilities. Similar to monolinguals, bilinguals showed greater activation in the left inferior frontal region [BA 45] in English than Chinese, suggesting that young bilinguals form language‐specific neural representations. The findings offer new insights to inform bilingual and cross‐linguistic models of language and literacy acquisition.     

Parental rearing behavior prospectively predicts adolescents’ risky decision‐making and feedback‐related electrical brain activity

The present study examined the role of parental rearing behavior in adolescents’ risky decision‐making and the brain's feedback processing mechanisms. Healthy adolescent participants (n = 110) completed the EMBU‐C, a self‐report questionnaire on perceived parental rearing behaviors between 2006 and 2008 (T1). Subsequently, after an average of 3.5 years, we assessed (a) risky decision‐making during performance of the Balloon Analogue Risk Task (BART); (b) event‐related brain potentials (ERPs) elicited by positive (gain) and negative feedback (loss) during the BART; and (c) self‐reported substance use behavior (T2). Age‐corrected regression analyses showed that parental rejection at T1 accounted for a unique and significant proportion of the variance in risk‐taking during the BART; the more adolescents perceived their parents as rejecting, the more risky decisions were made. Higher levels of perceived emotional warmth predicted increased P300 amplitudes in response to positive feedback at T2. Moreover, these larger P300 amplitudes (gain) significantly predicted risky decision‐making during the BART. Parental rearing behaviors during childhood thus seem to be significant predictors of both behavioral and electrophysiological indices of risky decision‐making in adolescence several years later. This is in keeping with the notion that environmental factors such as parental rearing are important in explaining adolescents’ risk‐taking propensities.     

Event‐related oscillations (EROs) and event‐related potentials (ERPs) comparison in facial expression recognition

The study aims to explore the significance of event‐related potentials (ERPs) and event‐related brain oscillations (EROs) (delta, theta, alpha, beta, gamma power) in response to emotional (fear, happiness, sadness) when compared with neutral faces during 180–250 post‐stimulus time interval. The ERP results demonstrated that the emotional face elicited a negative peak at approximately 230 ms (N2). Moreover, EEG measures showed that motivational significance of face (emotional vs. neutral) could modulate the amplitude of EROs, but only for some frequency bands (i.e. theta and gamma bands). In a second phase, we considered the resemblance of the two EEG measures by a regression analysis. It revealed that theta and gamma oscillations mainly effect as oscillation activity at the N2 latency. Finally, a posterior increased power of theta was found for emotional faces.