N400 Component Of Event-related Potential Research Articles

Neural correlates of recalled sadness, joy, and fear states: a source reconstruction EEG study.

The capacity to understand the others' emotional states, particularly if negative (e.g. sadness or fear), underpins the empathic and social brain. Patients who cannot express their emotional states experience social isolation and loneliness, exacerbating distress. We investigated the feasibility of detecting non-invasive scalp-recorded electrophysiological signals that correspond to recalled emotional states of sadness, fear, and joy for potential classification. The neural activation patterns of 20 healthy and right-handed participants were studied using an electrophysiological technique. Analyses were focused on the N400 component of Event-related potentials (ERPs) recorded during silent recall of subjective emotional states; Standardized weighted Low-resolution Electro-magnetic Tomography (swLORETA) was employed for source reconstruction. The study classified individual patterns of brain activation linked to the recollection of three distinct emotional states into seven regions of interest (ROIs). Statistical analysis (ANOVA) of the individual magnitude values revealed the existence of a common emotional circuit, as well as distinct brain areas that were specifically active during recalled sad, happy and fearful states. In particular, the right temporal and left superior frontal areas were more active for sadness, the left limbic region for fear, and the right orbitofrontal cortex for happy affective states. In conclusion, this study successfully demonstrated the feasibility of detecting scalp-recorded electrophysiological signals corresponding to internal and subjective affective states. These findings contribute to our understanding of the emotional brain, and have potential applications for future BCI classification and identification of emotional states in LIS patients who may be unable to express their emotions, thus helping to alleviate social isolation and sense of loneliness.

The Future of Psychotherapy Research and Neuroscience: Introducing the 4E/MoBI Approach to the Study of Patient–Therapist Interaction

The integration of neuroscience and psychotherapy research has long been a topic of interest in the field of mental health. A significant challenge in psychotherapy research is understanding the dyadic interaction between patient and therapist. This interaction is complex, emerging from a myriad of multi-level factors such as gestures, verbal communication, mentalization, and environmental influences. This article aims to present a roadmap for the future integration of neuroscience and psychotherapy research, addressing the complexities of human interaction. We introduce the 4E/MoBI approach, a framework that combines theoretical and methodological tools to study the dynamics of the brain, body, and environment in real-world settings. This approach emphasizes the use of physiological systems (e.g., heart and brain), behavioral interactions (e.g., conversations and eye-tracking), and environmental video recordings. Additionally, the scalable experimental design (SED) heuristic is discussed as a method to blend controlled experiments with real-world scenarios, allowing for the parametric testing of neurobehavioral markers. As a practical demonstration of the SED heuristic within the 4E/MoBI framework, a concrete experimental example using the N170 event-related potential (ERP) component is presented. While the N170 ERP component is not posited as the foundational marker in the field, it serves to illustrate the application of hypothesis-driven designs and analyses. The 4E/MoBI approach offers a promising avenue for the integration of neuroscience and psychotherapy research. By addressing existing gaps, such as the physiology and phenomenology of expertise in psychotherapy, this framework can foster a virtuous relationship between the two disciplines, paving the way for more comprehensive and nuanced understandings of therapeutic interactions.

The key role of the right posterior fusiform gyrus in music reading: an electrical neuroimaging study on 90 readers

IntroductionIn this study, we employed a combined electromagnetic recording technique, i.e., electroencephalogram (EEG)/event-related potentials (ERPs) plus standardized weighted low-resolution electromagnetic tomography (swLORETA), to investigate the neural mechanism subserving the orthographic processing of symbols in language and music. While much is known about word processing, the current literature remains inconclusive regarding music reading, as its mechanisms appear to be left lateralized in some cases (as suggested by music-alexia clinical case reports) and either right-sided or bilateral in others, depending on the study and the methodology used.MethodsIn this study, 90 right-handed participants with varying musical abilities and sexes performed an attentional selection task that involved the recognition of target letters and musical notes, while their EEG signals were recorded from 128 sites.ResultsThe occipito/temporal N170 component of ERPs (170–210 ms) was found strictly left-sided during letter selection and bilateral (with a right-hemispheric tendency) during note selection. Source reconstruction data indicated the preponderant engagement of the right posterior fusiform gyrus (BA19) for processing musical notes. Also involved were other brain regions belonging to the word reading circuit, including the left-sided visual word form area (VWFA) and frontal eye-fields (FEFs).DiscussionThis finding provides an explanation for the infrequent appearance of musical alexia cases (previously observed only in patients with left hemispheric lesions). It also suggests how musical literacy could be a rehabilitative and preventive factor for dyslexia, by promoting neuroplasticity and bilaterality in the reading areas.

Sensory Attenuation Deficit and Auditory Hallucinations in Schizophrenia: A Causal Mechanism or a Risk Factor? Evidence From Meta-Analyses on the N1 Event-Related Potential Component

BackgroundSensory attenuation (SA), the dampened perception of self-generated sensory information, is typically associated with reduced event-related potential signals, such as for the N1 component of auditory event-related potentials. SA, together with efficient monitoring of intentions and actions, should facilitate the distinction between self-generated and externally generated sensory events, thereby optimizing interaction with the world. According to many, SA is deficient in schizophrenia. The question arises whether altered SA reflects a sufficient mechanism to explain positive symptoms such as auditory hallucinations. A systematic association of reduced auditory SA in hallucinating patients would support this hypothesis. MethodsWe conducted a series of meta-analyses on 15 studies on auditory SA in which the N1 component of event-related potential–electroencephalogram signals was measured during talking (self-generated sensory signals condition) or when listening to prerecorded vocalizations (externally generated sensory signals condition). ResultsWe found that individuals with schizophrenia did show some auditory SA because their N1 signal was significantly attenuated in talking conditions compared with listening conditions. However, the magnitude of such attenuation was reduced in individuals with schizophrenia compared to healthy control participants. This phenomenon generalizes independently from the stage of the disease, the severity of positive symptoms, and whether patients have auditory hallucinations or not. ConclusionsThese findings suggest that reduced SA cannot be a sufficient mechanism for explaining positive symptoms such as auditory hallucinations in schizophrenia. Because reduced SA was also present in participants at risk of schizophrenia, reduced SA may represent a risk factor for the disorder. We discuss the implications of these results for clinical-cognitive models of schizophrenia.

Influence of conflicting prior information on action anticipation in soccer players: an ERP study.

Prior probability information and visual kinematic information are essential for action anticipation in athletes. The aims of this study were to examine how conflicting prior information influences anticipatory judgment in athletes vs. non-athletes and to explore the underlying cognitive mechanisms. The aim of Experiment 1 was to determine the moment when prior information influenced action anticipation in athletes vs. non-athletes. To that end, 17 semi-elite soccer goalkeepers and 18 non-athletes received prior information about the probability of the direction that a player on a video would kick a ball into the goal. Participants then anticipated the trajectory of the ball when the action of the player's kick on the video was truncated at the moment the foot contacted the ball (time T) or one frame (T-1; 50 ms) or two frames (T-2; 100 ms) before the foot-ball contact. The aim of Experiment 2 was to elucidate the adaptive cognitive-motor behavior exhibited by highly trained soccer players at the moment when their anticipatory performance was most influenced by prior information. Experiment 2 included 27 different semi-elite soccer players with many years of experience as a goalkeeper and 27 different non-athletes. Participants anticipated the direction of the kick when the kinematic action of the kicker at the moment the anticipatory performance of the participants was most influenced by prior information (as determined in Experiment 1) was congruent, incongruent, or neutral. Action anticipation accuracy and response time were evaluated for both experiments, whereas event-related potential components N1, N2, and P3 were assessed only in Experiment 2. The results of Experiment 1 showed that anticipatory accuracy was significantly higher among athletes than non-athletes and that anticipatory accuracy with directional information given was significantly higher than that when no prior information was given or when prior information without directional information was given (p < 0.001) for both T-1 (p's ≤ 0.034) and T-2 (p's < 0.001) occlusion points. In Experiment 2 using those two video occlusion times, the amplitude of the N1 component, which reflects selective attention to stimulus properties, was significantly higher in athletes than in non-athletes (p < 0.001). The amplitude of the N2 component, which has been associated with conflict monitoring, for the incongruent condition was significantly higher than that for both neutral (p < 0.001) and congruent (p < 0.001) conditions in athletes. Non-athletes exhibited no significant N2 amplitude differences for any prior information condition. Integrating prior information enhanced action anticipation in semi-elite soccer players, particularly 50 and 100 ms before the foot-ball contact. Semi-elite soccer players prioritized early selective attention and conflict monitoring of kinematic information, facilitating action anticipation using the prior information.

Using transcranial direct current stimulation (tDCS) to selectively modulate the face inversion effect and N170 event-related potentials.

We report a large study (n = 72) using combined transcranial direct current stimulation-electroencephalography (tDCS-EEG) to investigate the modulation of perceptual learning indexed by the face inversion effect. Participants were engaged with an old/new recognition task involving intermixed upright and inverted, normal and Thatcherized faces. The accuracy results showed anodal tDCS delivered at the Fp3 scalp area (cathode/reference electrode placed at Fp2) increased the behavioural inversion effect for normal faces versus sham/control and this covaried with a modulation of the N170 event-related potential component. A reduced inversion effect for normal faces was found on the N170 latency and amplitude versus sham/control, extending recent work that combined tDCS and EEG in circumstances where the behavioural face inversion effect was reduced. Our results advance understanding of the neural mechanisms responsible for perceptual learning by revealing a dissociation between the N170 amplitude and latency in response to the tDCS-induced modulation of the face inversion effect. The behavioural modulation of the inversion effect tracks the modulation of the N170 amplitudes, albeit it is negatively correlated (i.e., reduced inversion effect-larger N170 amplitude inversion effect, increased inversion effect-reduced N170 amplitude inversion effect). For the N170 latencies, the inversion effect is reduced by the tDCS protocol we use irrespective of any modulation of the behavioural inversion effect.

Neural correlates of face processing among preschoolers with fragile X syndrome, autism spectrum disorder, autism siblings, and typical development.

The current study examined patterns of event-related potential (ERP) responses during a face processing task in groups of preschoolers uniquely impacted by autism spectrum disorder (ASD), including (1) children with ASD; (2) children with fragile X syndrome (FXS); (3) children with familial risk for ASD, but without a diagnosis (i.e., ASIBs); and (4) a low-risk control (LRC) group. Children with FXS have a high incidence of ASD diagnoses, but there have been no studies of the ERP response to faces in children with FXS and little work focused on children with ASD who have cognitive impairment. The current study examined children's ERP responses to faces and houses in four groups: LRC (N = 28, age = 5.2 years), ASIB (N = 23, age = 5.5 years), FXS (N = 19, age = 5.82 years), and ASD (N = 23, age = 5.5 years). The FXS and ASD groups were characterized by the presence of cognitive impairment. Pictures of upright and inverted faces and houses were presented while recording EEG with a 128-channel system. The N170 occurred at about 200 ms post stimulus onset, was largest on the posterior-lateral electrodes, and was larger for faces than houses. The P1 and N170 ERP components were larger for the FXS group than for the other three groups. The N170 ERP amplitude for the ASD and ASIB groups was smaller than both the LRC and FXS groups, and the LRC and FXS groups had the largest N170 responses on the right side. No difference was found in N170 latency between groups. The similarity of the ASD and ASIB responses suggest a common genetic or environmental origin of the reduced response. Although children with FXS have a high incidence of ASD outcomes, they differed from ASD and ASIB children in this study. Specifically, the children with FXS were hyperresponsive to all stimulus types while the ASD and ASIB groups showed attenuated responses for specific stimuli.

Auditory cortical responses to abrupt lateralization shifts do not reflect the activity of hemifield-specific units involved in opponent coding of auditory space

Recent studies show that the classical model based on axonal delay-lines may not explain interaural time difference (ITD) based spatial coding in humans. Instead, a population-code model called “opponent channels model” (OCM) has been suggested. This model comprises two competing channels respectively for the two auditory hemifields, each with a sigmoidal tuning curve. Event-related potentials (ERPs) to ITD-changes are used in some studies to test the predictions of this model by considering the sounds before and after the change as adaptor and probe stimuli, respectively. It is assumed in these studies that the former stimulus causes adaptation of the neurons selective to its side, and that the ERP N1–P2 response to the ITD-change is the specific response of the neurons with selectivity to the side of probe sound. However, these ERP components are known as a global, non-specific acoustic change complex of cortical origin evoked by any change in the auditory environment. It probably does not genuinely reflect the activity of some stimulus-specific neuronal units that have escaped the refractory effect of the preceding adaptor, which means a violation of the crucial assumption in an adaptor-probe paradigm. To assess this viewpoint, we conducted two experiments. In the first one, we recorded ERPs to abrupt lateralization shifts of click trains having various pre- and post-shift ITDs within the physiological range of −600μs to +600μs. Magnitudes of the ERP components P1, N1, and P2 to these ITD-shifts did not comply with the additive behavior of partial probe responses presumed for an adaptor-probe paradigm, casting doubt on the accuracy of testing sensory coding models by using ERPs to abrupt lateralization changes. Findings of the second experiment, involving ERPs to conjoint outwards/transverse shift stimuli also supported this conclusion.

A randomized cross-over trial investigating the neurocognitive effects of acute exercise on face recognition in children with autism spectrum disorder.

Difficulties in face recognition contribute to social-cognitive problems in autistic children. Evidence on behavioral interventions targeting this cognitive domain is limited. In non-autistic individuals, a single exercise session is known to elicit temporary benefits for several cognitive functions. Our study investigates whether acute aerobic exercise influences face recognition in autistic children. In a randomized order, 29 participants completed a 20-min moderately-intense cycling bout on an ergometer and a control condition. Before and after each condition, participants categorized Mooney faces and instruments during a computerized cognitive task. Simultaneously, the N170 component of event-related potentials and pupil size were recorded using electroencephalography and eyetracking, respectively. As indicated by a greater increase of reaction time in the exercise compared to the control condition, the results revealed impaired face recognition following aerobic exercise. This effect was accompanied by a lower decrease of the positive N170 amplitude and a trend towards a greater constriction of the pupil size in the exercise compared to the control condition. Our findings highlight the interplay of the physiological state and face recognition in autistic children. Exercise-induced impairments in this social-cognitive ability may be due to an interference with the learning effect that is typically seen for the structural encoding of faces.

Neurophysiological indices of face processing in people with psychosis and their siblings: An event-related potential study.

People with schizophrenia experience difficulties with social interactions. One contributor to these social deficits is dysfunction in processing facial features and facial emotional expressions. However, it is not known whether face processing deficits are evident in those with other psychotic disorders or in those genetically at-risk for psychosis (i.e., first-degree relatives of those with psychosis). We assessed event-related potentials (ERPs) during a facial and emotion processing task in 100 people with a diagnosis of schizophrenia or another psychotic condition (PSY), 32 of their siblings (SIB) and 45 healthy comparison participants (CTL). In separate blocks, participants identified the sex (male or female) or emotion (happy, angry, neutral) of faces. In a comparison condition, participants indicated whether buildings had one or two floors. ERPs were examined in two stages. First, we compared ERPs across the emotion, sex and building identification conditions. Second, we compared ERPs among the three different facial emotions. PSY exhibited significantly lower amplitudes over parietal-occipital regions between 111 and 151 ms when viewing faces but not buildings than CTL, consistent with a face-selective N170 ERP component deficit. The SIB group was intermediate for faces, but not significantly different than PSY or CTL. During emotion identification, all three groups showed increased N170 amplitudes to angry and happy versus neutral expressions, with no group differences. In follow up analyses, we examined differences between PSY with or without affective psychosis, and differences between those with schizophrenia versus other psychotic disorders; there were no significant differences in these analyses. Face processing deficits assessed with ERPs were observed in a group of diverse psychotic disorders, though deficits were not seen to be modulated by facial emotion expression. Additionally, N170 deficits are not evident in siblings of those with PSY.

Neural Indicators of Visual Andauditory Recognition of Imitative Words on Different De-Iconization Stages.

The research aims to reveal neural indicators of recognition for iconic words and the possible cross-modal multisensory integration behind this process. The goals of this research are twofold: (1) to register event-related potentials (ERP) in the brain in the process of visual and auditory recognition of Russian imitative words on different de-iconization stages; and (2) to establish whether differences in the brain activity arise while processing visual and auditory stimuli of different nature. Sound imitative (onomatopoeic, mimetic, and ideophonic) words are words with iconic correlation between form and meaning (iconicity being a relationship of resemblance). Russian adult participants (n = 110) were presented with 15 stimuli both visually and auditorily. The stimuli material was equally distributed into three groups according to the criterion of (historical) iconicity loss: five explicit sound imitative (SI) words, five implicit SI words and five non-SI words. It was established that there was no statistically significant difference between visually presented explicit or implicit SI words and non-SI words respectively. However, statistically significant differences were registered for auditorily presented explicit SI words in contrast to implicit SI words in the N400 ERP component, as well as implicit SI words in contrast to non-SI words in the P300 ERP component. We thoroughly analyzed the integrative brain activity in response to explicit IS words and compared it to that in response to implicit SI and non-SI words presented auditorily. The data yielded by this analysis showed the N400 ERP component was more prominent during the recognition process of the explicit SI words received from the central channels (specifically Cz). We assume that these results indicate a specific brain response associated with directed attention in the process of performing cognitive decision making tasks regarding explicit and implicit SI words presented auditorily. This may reflect a higher level of cognitive complexity in identifying this type of stimuli considering the experimental task challenges that may involve cross-modal integration process.

Electrocortical effects of detachment and reinterpretation on the regulation of negative emotion

Research has suggested a contradictory effect between detachment and reinterpretation, two distinct tactics of cognitive reappraisal, in the regulation of negative emotion. The reasons for this contradictory effect remain unclear. The present study explored the differences between these tactics in terms of potential early processes and neural mechanisms, comparing psychophysiological differences using event-related potentials (ERPs) in the regulation of negative emotion. Thirty college students were required to perform an emotion regulation task, in which they naturally viewed or applied a given emotion regulation strategy towards negative pictures. The results demonstrated that both tactics reduced emotional experiences (decrease of arousal and increase of valence). Reinterpretation was associated with reductions in the late positive potential (LPP) in the late time window, while detachment was not. Detachment showed a lower amplitude in the N1 and N2 ERP components and a higher P2 amplitude than reinterpretation. The differences in early ERP components (N1, N2, and P2) predicted the reduction of LPP amplitude. These findings reveal the differential effects of these tactics on emotional experience and neural responses and highlight the significance of early processes on emotion across the time course of cognitive reappraisal.

Stereotyping Among Graduate Students in Mental Health Fields: An EEG Study

Counselors are obligated to work effectively with diverse groups, yet stereotyping and biases can impede counselors’ efforts. Understanding implicit processes in social cognition among counselors is important because implicit stereotyping and biases can negatively influence counselors’ work. Investigation of cognitive processes through electroencephalography (EEG) can illuminate implicit tendencies that potentially lead to microaggressions toward clients. In this study, we tested the hypothesis that graduate students in mental health fields would show indicators of stereotyping in a priming experiment that measured stereotyping implicitly. Both neural (N400 event-related potential component) and behavioral (reaction time) measures were used as indexes for stereotyping. The results showed neural and behavioral markers of stereotyping toward Black men and White women in a sample of graduate students in mental health fields composed of mostly White women. Implications for counseling practice and research are discussed.

[Specificity of visual event-related potentials to subthreshold presentation of erotic pictures in pedophilia].

To study visual event-related potentials (ERPs) associated with presentation of erotic pictures in backward masking condition in order to investigate perception, attention and information processing underlying the initiation and maintenance of abnormal sexual behavior in pedophilia. Participants (58 males committed sexual offenses against children) were divided into the pedophilia group (n=38) and the control group without disorders of sexual preference (n=20). Three types of stimuli were used: neutral pictures of nature (S1), adult heterosexual erotic pictures (S2) and erotic pictures with children (S3). Posterior N1 (N140) and anterior N1 (N120) and P3 (P320) ERP components were included in analysis. In both groups, the perception of erotic stimuli was accompanied by a significant increase in the amplitude and prolongation of the latency of the N140 and P320 components (p<0.001). N140 changes were characterized by right-hemispheric bias in both groups, however, asymmetry was observed for amplitude in the control group, and for latency - in the pedophilia group; besides, reactivity to S3 stimuli was weaker than to S2 ones in the pedophilia group. N120 amplitude was elevated significantly in response to S2 stimuli in the control group, and no changes were found in the pedophilia group. Between-group differences were revealed for early negative components N140 and N120, which parameters were entered as predictors into classification model based on discriminant analysis. The obtained accuracy of model was 87.23%. The specificity of neurophysiological reactions to erotic pictures in pedophilic patients corroborates the concept of disease as general neurodevelopmental disorder.

ERP indicators of situational empathy pain

This study aimed to validate a recent conceptualization proposed by Coll and colleagues (2017a) that defines empathic response as a situational, cognitively complex process requiring emotion identification and affective sharing. Sixty right-handed women university students (18–29 years) voluntarily participated in the study. We measured ratings for empathy pain to assess the individual differences in empathy. At the same time, we collected peak amplitudes of the event-related potentials (ERPs) components to empathic stimulations of painful faces or hand stimuli and neutral images. Electrophysiological results proved that the P2, N170, N2, and P3 ERP components were associated with the modulation of empathic responses. Participants with low empathic responses (p < 0.05) disclosed a larger frontal central N2 for the painful hands than for painful faces (p < .05) and a reduced temporoparietal N170 for painful hands compared to neutral ones. Furthermore, our results highlighted higher frontal central P3a and P3b to painful stimuli than controls (p ≤ 0.01). We explained these findings assuming that in identifying the emotional value of a stimulus, the emotional content can modulate the reorientation of attention and the in-memory updating process associated with the empathic response. Results are in line with Coll and colleagues' conceptualization of the empathic response that includes two cognitive processes, the identification of emotions, and affective sharing, related to the recognition of the emotional state of the other in the self.

Aging-Related Dissociation of Spatial and Temporal N400 in Sentence-Level Semantic Processing: Evidence From Source Analyses.

Age-related differences in sentence-level lexical-semantic processes have been extensively studied, based on the N400 component of event-related potential (ERP). However, there is still a lack of understanding in this regard at the brain-region level. This study explores aging effects on sentence-level semantic processing by comparing the characteristics of the N400 ERP component and brain engagement patterns within individual N400 time windows for two age groups (16 younger adults aged 24.38 ± 3.88 years and 15 older adults aged 67.00 ± 5.04 years) during sentence processing with different plausibility conditions. Our results demonstrated that the N400 effect according to the plausibility condition occurred in different temporal windows in the two age groups, with a delay in the older group. Moreover, it was identified that there was a distinct difference between the groups in terms of the source location of the condition-dependent N400 effect even though no significant difference was derived in its magnitude itself at the sensor-level. Interestingly, the source analysis results indicated that the two groups involved different functional networks to resolve the same semantic violations: the younger group activated the regions corresponding to the typical lexical-semantic network more, whereas the older group recruited the regions belonging to the multiple-demand network more. The findings of this study could be used as a basis for understanding the aging brain in a linguistic context.

Spatial selectivity of the visual duration aftereffect in the sub-second range: An event-related potentials study

Prolonged adaptation to one duration biases the perception of subsequent durations in a phenomenon known as duration adaptation. There is controversy regarding the neural substrates of the visual duration aftereffect: some researchers have argued that duration adaptation occurs in early visual cortical areas, whereas others have argued for high-level visual areas. Investigation of spatial selectivity of the duration aftereffect could help reveal the neural mechanisms underlying duration adaptation. In the present study, we used event-related potentials (ERPs) to demonstrate spatial selectivity of the visual duration aftereffect in the sub-second range. We measured the duration aftereffect at a 20° adapt-test distance that spanned 10° on either side of fixation. Our results revealed that duration adaptation first affected the N1 ERP component and then influenced the contingent negative variation (CNV) component. Moreover, the CNV component showed position effects in the temporal encoding stage, and the post-stimulus positive component was subject to a duration effect but not a position effect. These findings indicate that sub-second duration coding is closely linked to the early processing of the visual cortex. Moreover, the adaptation not only affects the earlier temporal coding stage, but also the later temporal processing stage.

Identifying Age Based Maturation in the ERP Response to Faces in Children With Autism: Implications for Developing Biomarkers for Use in Clinical Trials.

Recent proposals have suggested the potential for neural biomarkers to improve clinical trial processes in neurodevelopmental conditions; however, few efforts have identified whether chronological age-based adjustments will be necessary (as used in standardized behavioral assessments). Event-related potentials (ERPs) demonstrate early differences in the processing of faces vs. objects in the visual processing system by 4 years of age and age-based improvement (decreases in latency) through adolescence. Additionally, face processing has been proposed to be related to social skills as well as autistic social-communication traits. While previous reports suggest delayed latency in individuals with autism spectrum disorder (ASD), extensive individual and age based heterogeneity exists. In this report, we utilize a sample of 252 children with ASD and 118 children with typical development (TD), to assess the N170 and P100 ERP component latencies (N170L and P100L, respectively), to upright faces, the face specificity effect (difference between face and object processing), and the inversion effect (difference between face upright and inverted processing) in relation to age. First, linear mixed models (LMMs) were fitted with fixed effect of age at testing and random effect of participant, using all available data points to characterize general age-based development in the TD and ASD groups. Second, LMM models using only the TD group were used to calculate age-based residuals in both groups. The purpose of residualization was to assess how much variation in ASD participants could be accounted for by chronological age-related changes. Our data demonstrate that the N170L and P100L responses to upright faces appeared to follow a roughly linear relationship with age. In the ASD group, the distribution of the age-adjusted residual values suggest that ASD participants were more likely to demonstrate slower latencies than would be expected for a TD child of the same age, similar to what has been identified using unadjusted values. Lastly, using age-adjusted values for stratification, we found that children who demonstrated slowed age-adjusted N170L had lower verbal and non-verbal IQ and worse face memory. These data suggest that age must be considered in assessing the N170L and P100L response to upright faces as well, and these adjusted values may be used to stratify children within the autism spectrum.

Event-Related Potentials to Speech Relate to Speech Sound Production and Language in Young Children

ABSTRACT This research was funded through the American Speech and Hearing Foundation’s 2012 StudentResearch Grant in Early Childhood Language Development awarded to Vanessa Harwood as well as an anonymous generous donation to Haskins Laboratories. Electrophysiological measures of language within early childhood provide important information about neurolinguistic development. We investigated associations between amplitude and latency of the P1 and N2 event-related potential components in response to spoken pseudowords, and clinical measures of language performance within a sample of 58 typically developing children between 24 and 48 months. N2 amplitude differences between repeated and new tokens were correlated with measures of expressive and receptive language and speech sound production. Phonemic sensitivity measured by the N2 component may reflect the integrity of neural networks that are important for speech perception and production in young children.

Neural mechanisms of inhibitory control deficits in obesity revealed by P3 but not N2 event-related potential component

The lack of inhibitory control toward foods may cause unhealthy eating behavior and lead to obesity. However, previous research failed to reach consensus on the alterations in event-related potential (ERP) markers of inhibitory control, i.e., N2 and P3. We hypothesized that the ERP effects of inhibitory control reported in previous food-based Go/NoGo studies might be obscured by non-inhibitory processes associated with stimulus probability. We designed two food-based Go/NoGo tasks composed of stimuli with the same type and frequency of occurrence (60% non-foods, 20% high-calorie foods, 20% low-calorie foods), one with response inhibition toward high- and the other toward low-calorie foods. Such an experimental design allowed us to isolate neural activity associated with inhibitory control from that associated with non-inhibitory processes by constructing ERP difference waves between NoGo and Go trials with the same frequency of occurrence. Electroencephalography data were collected from 32 obese participants and 29 normal-weight controls. Obese participants showed significantly lower accuracy in NoGo trials than normal-weight controls in both tasks. ERP data suggested inhibition-related effects for P3 (P3d) but not N2 in the difference waves, and obese participants showed significantly decreased P3d amplitudes than normal-weight controls in both tasks. In addition, we found that across both groups, individuals with larger waist-to-hip ratios showed smaller P3d amplitudes in both tasks, while such correlations between body mass index and P3d amplitude were only observed in the high-calorie task. Our findings suggest that the decreased effect of P3, not N2, might reflect the neural substrate of inhibitory control deficits in obese people. Thus, P3 could serve as an important neural marker in the future development of new therapeutic strategy that aims to improve inhibitory control in obesity.