Larger P3 Research Articles

The influence of social power on neural responses to emotional conflict.

BackgroundMajor power theories assume that social power can play an important role in an individual’s goal-related behaviors. However, the specific psychological mechanisms through which this occurs remain unclear. Some studies suggested that having power enhanced individuals’ goal-related behaviors, by contrast, other studies suggested that low-power individuals were associated with a greater performance in goal-directed tasks. We were particularly interested in how social power changes individuals’ goal-related behaviors during an emotional face-word Stroop task.MethodSocial power was primed by asking participants to recall a past situation in which they were in a position of power (high-power individuals), or a situation in which they were lacking power (low-power individuals). Afterward, participants were asked to complete an emotional face-word Stroop task. In the task, words representing specific emotions were written in a prominent red color across a face, and these words and facial expressions were either congruent or incongruent. The participant’s task was to judge the emotion of the face while ignoring the red emotional words.ResultsOur behavioral data showed that these individuals displayed faster reaction time and better accuracy in congruent conditions, slower reaction time for fearful faces and worse accuracy for happy faces in both incongruent and congruent conditions. The event-related potential analyses showed that, compared with low-power individuals, high-power individuals showed greater P1 amplitudes when faced with emotional stimuli (both incongruent and congruent conditions), indicating that power affects individuals’ attention in the early sensory processing of emotional stimuli. For the N170 component, low-power individuals showed more negative amplitudes when facing emotional stimuli, indicated that low-power individuals paid more attention to the construct information of emotional stimuli. For the N450 component, compared with congruent conditions, incongruent conditions elicited more negative amplitudes for both high- and low-power individuals. More importantly, fearful faces provoked enhanced P1 amplitudes in incongruent conditions than in congruent conditions only for low-power individuals, while, happy faces elicited larger P1 amplitudes in congruent conditions than in incongruent conditions only for high-power individuals. The findings suggested that during the initial stage of stimuli processing low-power individuals are more sensitive to negative stimuli than high-power individuals.ConclusionThese findings provided electrophysiological evidence that the differences in the emotional conflict process between high- and low-power individuals mainly lies in the early processing stages of emotional information. Furthermore, evidence from P1 and N170 showed that there was also a redistribution of attentional resources in low-power individuals.

Working memory impairment in children orphaned by parental HIV/AIDS: An event-related potentials study

ABSTRACT A large body of literature has established that children orphaned by HIV/AIDS (‘AIDS orphans’) face numerous challenges, such as parental death, poverty, disrupted school attendance and stigma. All of these early life adversities can have long-lasting effects on brain function, especially the executive functions. Working memory, as one of the most studied aspects of executive functions, is also reported to be impaired in children with early adversity. However, limited data are available regarding how early life adverse events affect the neural dynamic associated with working memory processing in AIDS orphans. This study applied the electroencephalogram (EEG) technique to investigate the working memory process in 81 AIDS orphans and 62 non-orphan controls with n-back tasks. Results from EEG analysis and time-frequency analysis showed that AIDS orphans displayed smaller N2 and larger P2, P3 activation as well as enhanced theta and attenuated alpha band oscillations compared to the controls. The present findings indicated a deficit in working memory process in AIDS orphans and suggested that this deficit might be due to the impairments in attention allocation, detection and classification of stimuli and updating process in working memory.

An Event-Related Brain Potential (ERP) Study of Complex Anaphora in Spanish.

This study examines the event- related brain potential (ERP) of 25 Mexican monolingual Spanish-speakers when reading Spanish sentences with single entity anaphora or complex anaphora. Complex anaphora is an expression that refer to propositions, states, facts or events while, a single entity anaphora is an expression that refers back to a concrete object. Here we compare the cognitive cost in processing a single entity anaphora [éstafeminine; La renuncia (resignation)] from a complex anaphora [estoneuter; La renuncia fue aceptada (The resignation was accepted)]. Ésta elicited a larger positive peak at 200 ms, and esto elicited a larger frontal negativity around 400 ms. The positivity resembles the P200 component, and its amplitude is thought to represent an interaction between predictive qualities in sentence processing (i.e., graphical similarity and frequency of occurrence). Unlike parietal negativities (typical N400), frontal negativities are thought to represent the ease by which pronouns are linked with its antecedent, and how easy the information is recovered from short-term memory. Thus, the complex anaphora recruited more cognitive resources than the single entity anaphora. We also included an ungrammatical control sentence [éstemasculine; La renuncia (resignation)] to better understand the unique processes behind complex anaphoric resolution, as opposed to just general difficulty in sentence processing. In this case, event-related potentials (ERPs) elicited by éstemasculine and éstafeminine were compared. Again, ésta elicited a larger P200. However, different from the experimental condition, a left anterior negativity (LAN) effect was observed for éste; the ungrammatical condition. Altogether, the present research provides electrophysiological evidence indicating that demonstrative pronouns with different morphosyntactic features (i.e., gender) and discourse parameters (i.e., single entity or complex referent) interact during the first stage of anaphoric processing of anaphora. This stage initiated as early as 200 milliseconds after the pronoun onset and probably ends around 400 ms.

Abnormally Large Baseline P300 Amplitude Is Associated With Conversion to Psychosis in Clinical High Risk Individuals With a History of Autism: A Pilot Study.

Psychosis rates in autism spectrum disorder (ASD) are 5–35% higher than in the general population. The overlap in sensory and attentional processing abnormalities highlights the possibility of related neurobiological substrates. Previous research has shown that several electroencephalography (EEG)-derived event-related potential (ERP) components that are abnormal in schizophrenia, including P300, are also abnormal in individuals at Clinical High Risk (CHR) for psychosis and predict conversion to psychosis. Yet, it is unclear whether P300 is similarly sensitive to psychosis risk in help-seeking CHR individuals with ASD history. In this exploratory study, we leveraged data from the North American Prodrome Longitudinal Study (NAPLS2) to probe for the first time EEG markers of longitudinal psychosis profiles in ASD. Specifically, we investigated the P300 ERP component and its sensitivity to psychosis conversion across CHR groups with (ASD+) and without (ASD–) comorbid ASD. Baseline EEG data were analyzed from 304 CHR patients (14 ASD+; 290 ASD–) from the NAPLS2 cohort who were followed longitudinally over two years. We examined P300 amplitude to infrequent Target (10%; P3b) and Novel distractor (10%; P3a) stimuli from visual and auditory oddball tasks. Whereas P300 amplitude attenuation is typically characteristic of CHR and predictive of conversion to psychosis in non-ASD sample, in our sample, history of ASD moderated this relationship such that, in CHR/ASD+ individuals, enhanced – rather than attenuated - visual P300 (regardless of stimulus type) was associated with psychosis conversion. This pattern was also seen for auditory P3b amplitude to Target stimuli. Though drawn from a small sample of CHR individuals with ASD, these preliminary results point to a paradoxical effect, wherein those with both CHR and ASD history who go on to develop psychosis have a unique pattern of enhanced neural response during attention orienting to both visual and target stimuli. Such a pattern stands out from the usual finding of P300 amplitude reductions predicting psychosis in non-ASD CHR populations and warrants follow up in larger scale, targeted, longitudinal studies of those with ASD at clinical high risk for psychosis.

How Social Power Affects the Processing of Angry Expressions: Evidence From Behavioral and Electrophysiological Data.

With the help of event-related potentials (ERPs), the present study used an oddball paradigm to investigate how both individual and target power modulate neural responses to angry expressions. Specifically, participants were assigned into a high-power or low-power condition. Then, they were asked to detect a deviant angry expression from a high-power or low-power target among a series of neutral expressions, while behavioral responses and electroencephalogram (EEG) were recorded. The behavioral results showed that high-power individuals responded faster to detect angry expressions than low-power individuals. The ERP analysis showed that high-power individuals showed larger P3 amplitudes in response to angry expressions than low-power individuals did. Target power increased the amplitudes of the P1, VPP, N3, and P3 in response to angry expressions did, but decreased the amplitudes of the N1 and N170 in response to angry expressions. The present study extended previous studies by showing that having more power could enhance individuals’ neural responses to angry expressions in the late-stage processes, and individuals could show stronger neural responses to angry expressions from high-power persons in both the early‐ and late-stage processes.

Abnormally Large Baseline P300 Amplitude Is Associated With Conversion to Psychosis in Clinical High Risk Individuals With a History of Autism: A Pilot Study

Abnormally Large Baseline P300 Amplitude Is Associated With Conversion to Psychosis in Clinical High Risk Individuals With a History of Autism: A Pilot Study

ERP and behavioural measures of cognitive effort associated to forget negative and neutral words

The cognitive effort associated with remembering (R) vs forgetting (F) neutral and negative words was analyzed through a visual detection task integrated in an item-method directed forgetting task. Thirty-three younger adults participated in the experiment while their electrophysiological activity was registered in the study phase. The results shown: (1) negative words evoked more positive ERPs than neutral words on frontal regions, suggesting a preferential processing of negative words. (2) F-cues evoked more positive ERPs than R-cues did for neutral rather than negative words between 500 and 900 ms. This effect could reflect the difficulty in implementing inhibitory mechanisms on negative words. (3) At visual detection task, RTs for post-F probes were longer than for post-R probes. In 350–550 ms time window, ERPs were more positive for post-F probes than post-R probes in over right frontal regions and left medial parietal regions. Additionally, larger P2 were evoked by post-F negative probes than by post-R negative and post-F neutral ones. (4) In recognition test, participants recognized more negative TBF words than neutral ones. The ERP and behavioral results indicate that forgetting is more difficult than remembering, especially when words have a negative content, which implies a greater recruitment of parietal and frontal regions.

Acute moderate-intensity exercise generally enhances neural resources related to perceptual and cognitive processes: A randomized controlled ERP study

ObjectivesTo examine the effect of acute exercise on multiple ERP components in young adults and to determine whether acute moderate-intensity exercise exerts a general or selective effect on a cognitive task requiring basic information processing and the inhibitory aspect of executive function. DesignA randomized controlled trial design. MethodsForty young adults were randomly assigned to one of two experimental groups: (a) an acute bout of moderate-intensity exercise (n = 20) or (b) a non-exercise control (n = 20). The participants completed congruent and incongruent trials of a flanker task at baseline and after the treatments (exercise or control) while event-related potentials (ERPs) were recorded. ResultsAcute moderate-intensity exercise facilitated response times for both congruent and incongruent flanker conditions. Larger P2, N2c, and P3 amplitudes were observed under both conditions following the exercise. No effects on accuracy or latency were found. ConclusionThese findings suggest that acute moderate-intensity exercise generally influences basic information processing and the inhibitory aspect of executive function in healthy young adults. The ERP data imply that general facilitation occurs in the perceptual, stimulus classification and evaluation processes.

The effect of shared distinctiveness on source memory: An event-related potential study

An illusory correlation (IC) is the erroneous perception that two actually uncorrelated categories are correlated. The Shared Distinctiveness Approach (SDA) explains ICs with heightened accessibility of distinctive category combinations in episodic memory. However, empirical evidence for this approach is heterogeneous. In the present event-related potential (ERP) study, we exploited the fact that more distinctive items elicit larger P300 responses than less distinctive items, which potentially predict subsequent memory performance differences for such items. Distinctiveness at encoding was created by presenting words that differed from frequently presented, positive words in valence, font color, or both. We hypothesized that shared distinctiveness (deviation in both color and valence) would lead to an enhanced P300 subsequent memory effect (SME), better source memory performance, and an overestimation of the frequency of shared distinctive items. Behavioral results indicated the presence of shared distinctiveness effects on source memory and frequency estimation. Unexpectedly, memory also was enhanced for positive items in the frequent color. This pattern also was reflected in the P300 for highly positive and negative items. However, shared distinctiveness did not modulate the P300 SME, indicating that the processing of distinctive features might only indirectly contribute to better encoding. This study shows that shared distinctiveness indeed is associated with better source memory and ICs. Because effects were observed for the most frequent and the least frequent category combination, our results imply that the processing of distinctiveness might involve attention allocation to diametrical category combinations, thereby accentuating the differences between the categories.

Long-Term Musical Training Alters Auditory Cortical Activity to the Frequency Change.

Objective: The ability to detect frequency variation is a fundamental skill necessary for speech perception. It is known that musical expertise is associated with a range of auditory perceptual skills, including discriminating frequency change, which suggests the neural encoding of spectral features can be enhanced by musical training. In this study, we measured auditory cortical responses to frequency change in musicians to examine the relationships between N1/P2 responses and behavioral performance/musical training.Methods: Behavioral and electrophysiological data were obtained from professional musicians and age-matched non-musician participants. Behavioral data included frequency discrimination detection thresholds for no threshold-equalizing noise (TEN), +5, 0, and −5 signal-to-noise ratio settings. Auditory-evoked responses were measured using a 64-channel electroencephalogram (EEG) system in response to frequency changes in ongoing pure tones consisting of 250 and 4,000 Hz, and the magnitudes of frequency change were 10%, 25% or 50% from the base frequencies. N1 and P2 amplitudes and latencies as well as dipole source activation in the left and right hemispheres were measured for each condition.Results: Compared to the non-musician group, behavioral thresholds in the musician group were lower for frequency discrimination in quiet conditions only. The scalp-recorded N1 amplitudes were modulated as a function of frequency change. P2 amplitudes in the musician group were larger than in the non-musician group. Dipole source analysis showed that P2 dipole activity to frequency changes was lateralized to the right hemisphere, with greater activity in the musician group regardless of the hemisphere side. Additionally, N1 amplitudes to frequency changes were positively related to behavioral thresholds for frequency discrimination while enhanced P2 amplitudes were associated with a longer duration of musical training.Conclusions: Our results demonstrate that auditory cortical potentials evoked by frequency change are related to behavioral thresholds for frequency discrimination in musicians. Larger P2 amplitudes in musicians compared to non-musicians reflects musical training-induced neural plasticity.

Relationship of regular physical activity with neuroelectric indices of interference processing in young adults.

The relationship of physical activity with interference processing was examined using behavioral and neuroelectrical measures in young adults divided into more active and less active groups. The participants completed Stroop (i.e., color-naming) and reverse Stroop (i.e., word-meaning) tasks that differed in the level of difficulty while event-related potentials were assessed. In the low interference Stroop task, participants were asked to respond to the ink color of the word, while the meaning was either congruent or incongruent with the color. In the high interference reverse Stroop task, participants had to indicate the meaning of colored words while ignoring the color of the font. The results indicated that young adults in the more active group exhibited a shorter response time (RT) and a lower intra-individual variability of RT than did those in the less active group. These behavioral differences were associated with larger P2 and P3 and smaller N450 amplitudes in the Stroop task and with larger P2 and N2 and smaller N450 amplitudes in the reverse Stroop task. No differences were observed in the contingent negative variation (CNV) between the groups. These findings suggest that, for young adults, regular physical activity is positively associated with a better neural efficiency in resource allocation for tasks that require the ability to inhibit cognitive interference and provide evidence for the potential neural mechanisms underlying the improved Stroop performance.

Event-Related Potential to Conscious and Nonconscious Emotional Face Perception in Females with Autistic-Like Traits.

This study explored the electrocortical correlates of conscious and nonconscious perceptions of emotionally laden faces in neurotypical adult women with varying levels of autistic-like traits (Autism Spectrum Quotient—AQ). Event-related potentials (ERPs) were recorded during the viewing of backward-masked images for happy, neutral, and sad faces presented either below (16 ms—subliminal) or above the level of visual conscious awareness (167 ms—supraliminal). Sad compared to happy faces elicited larger frontal-central N1, N2, and occipital P3 waves. We observed larger N1 amplitudes to sad faces than to happy and neutral faces in High-AQ (but not Low-AQ) scorers. Additionally, High-AQ scorers had a relatively larger P3 at the occipital region to sad faces. Regardless of the AQ score, subliminal perceived emotional faces elicited shorter N1, N2, and P3 latencies than supraliminal faces. Happy and sad faces had shorter N170 latency in the supraliminal than subliminal condition. High-AQ participants had a longer N1 latency over the occipital region than Low-AQ ones. In Low-AQ individuals (but not in High-AQ ones), emotional recognition with female faces produced a longer N170 latency than with male faces. N4 latency was shorter to female faces than male faces. These findings are discussed in view of their clinical implications and extension to autism.

To move or not to move: An ERP study on the processing of fictive and literal motion expressions

This study used electroencephalographic evoked response potentials to investigate the processing of fictive motion and literal motion during natural language comprehension. A hypothesis is that the motion component of a verb is preserved in both literal and fictive motion constructions (‘The army/The bridge crossed the river’). However, the incorporation of a motion-event frame into fictive motion constructions requires reanalysis or reconstruction both syntactically and semantically. Comparing fictive motion constructions to literal motion constructions revealed a larger P300 at presentation of the subject noun phrase, a larger P600 at motion verbs, and an N400 modulation on the sentence-final complement noun phrases. These results suggest that the processing of fictive motion requires increased cognitive effort relative to literal motion condition, particularly computations related to thematic role assignment and semantic unification to construct a motion-event frame involving mental simulation of motion.

P300 response modulation reflects breaches of non-probabilistic expectations

In oddball paradigms, infrequent stimuli elicit larger P300 event related potentials (ERPs) than frequent ones. One hypothesis is that P300 modulations reflect the degree of “surprise” associated with unexpected stimuli. That is the P300 represents how unlikely the stimulus is and this signal is then used to update the observer’s expectations. It could be hypothesized that P300 is modulated by any factor affecting an observer’s expectations, not only target probability. Alternatively, the P300 may reflect an evaluative process engaged whenever a discrepancy between task context and sensory inputs arises, irrespective of the latter probability. In previous ERP studies, stimulus probability was often the only determinant of task set confounding the effects of stimulus probability and set stimulus discrepancy. In this study, we used a speeded luminance detection task. The target was preceded by a central cue that predicted its location. The probability that the target was valid, i.e. would appear at the cued location was manipulated by varying the reliability of the cue. Reaction times were modulated by probabilistic expectations based on cue reliability and target validity while P300 was affected by target validity only. We conclude that increased P300 amplitude reflects primarily breaches of non-probabilistic expectations, rather than target probability.

Scanning acoustic short-term memory: Evidence for two subsystems with different time-course and memory strength

We studied the cognitive processes involved in pure acoustic memory retrieval using ERPs and independent component analysis (ICA) of the ERPs. We used a modified Sternberg task with pure tones as memory items, with 3 memory set size conditions (2, 4, or 6 tones), and a control condition in which no task-relevant tone was presented (tones replaced by white-noise segments). Participants reported the presence or absence of a probe tone in the memory set. EEG signals were recorded using a BioSemi ActiveTwo system, with 64 active electrodes following the 10–10 system and average-mastoids reference. A P3 component, at electrode POz, was elicited by the probe when items were to be held in memory, no P3 was observed in control trials. With an increase in memory load, P3 amplitude decreased, accuracy was lower, and response time (RT) longer. There was a clear recency effect, in the electrophysiological and behavioral results reflected in a larger P3, shorter RT, and higher accuracy, when the probe matched the last tone of a sequence than when it matched any of the other presented tones, regardless of memory load. P3 amplitude and behavioral results were similar across all the other serial positions and loads. The results suggest that acoustic memory for pure tones is mediated by two subsystems: one encoding the last item with high probability, and another for all other serial positions. ICA of the ERPs isolated parieto-occipital ICA components with larger activations for probes that matched the last serial position than for earlier ones, and an anterior component that had little activation for the last serial positions and large activations for all earlier ones, corroborating the two-systems theory.

Sensitivity to negative feedback among children and adolescents: An ERP study comparing developmental differences between high-worriers and low-worriers.

Neurodevelopmental imbalance models suggest that asynchrony in the maturation of interconnections between brain regions contributes to adolescents being more sensitive to emotionally salient events (e.g., negative feedback) than children. There may, however, be important individual differences to consider when investigating sensitivity to negative feedback. For example, worriers tend to have a greater sensitivity to negative feedback than low-worriers. Thus, it may be that adolescents' sensitivity to negative feedback is tied to worry. One way to test this question is to compare worriers to nonworriers separately for both children and adolescents. If only adolescent worriers are sensitive to negative feedback (i.e., low-worriers are not), then sensitivity to negative feedback may be linked to higher rates of worry. If however, adolescent nonworriers also have a sensitivity, then adolescents in general may be sensitive to negative feedback. The current study (N = 100, Mage = 11.26, standard deviation = 1.71) used event-related potentials (ERPs) to investigate neural differences in sensitivity to negative feedback among adolescents and children with high and low levels of worry. For both children and adolescents, worriers had a larger P3 amplitude to negative feedback than nonworriers. This difference, however, was smaller among the adolescents (i.e., adolescent nonworriers also had a large P3 amplitude to negative feedback). Our results support neurodevelopmental imbalance models that suggest adolescents in general are sensitive to emotionally salient events, such as receiving negative feedback.

ERP measures of the effects of age and bilingualism on working memory performance

Previous research has suggested that bilinguals may exhibit cognitive advantages over those who are monolingual, although conflicting results have been reported. This advantage may be heightened in older adults, because of age-related cognitive decline. However, the effects of bilingualism on working memory performance in older adults remain unknown. The current study uses electroencephalography to measure brain activity (event-related potential; ERP) differences between young and older monolinguals and bilinguals during a delayed matching-to-sample task. Although there were no effects of bilingualism in behavioral measures, differences were observed in electrophysiological measures. While no Age by Language interaction was observed, several main effects were identified. Compared to young adults, older adults exhibited smaller N2 amplitudes and larger P2 and P3b amplitudes in the medium and high load conditions. Older adults also displayed an increased slow wave amplitude that occurred in conjunction with increased reaction time. ERP differences during difficult tasks in older adults suggest the use of compensatory mechanisms to maintain similar performance to the young adults. Bilinguals exhibited smaller N2 and larger P2 and P3b amplitudes than monolinguals. ERP differences observed in bilinguals may reflect differences in cognitive processing. However, in the absence of performance differences between monolinguals and bilinguals, interpreting a bilingual advantage in working memory processing is difficult.

Temporal features of individual and collective self-referential processing: an event-related potential study

BackgroundIndividual and collective self are two fundamental self-representations and are important to human experience. The present study aimed to investigate whether individual and collective self have essential difference in neural mechanism.MethodsEvent-related potentials were recorded to explore the electrophysiological correlates of individual and collective self in a self-referential task in which participants were asked to evaluate whether trait adjectives were suitable to describe themselves (individual self-referential processing), a famous person (individual non-self-referential processing), Chinese (collective self-referential processing) or American (collective non-self-referential processing).ResultsAt the early stages, results showed that larger P2 and smaller N2 amplitudes were elicited by individual self-referential than by individual non-self-referential processing whereas no significant differences were observed between collective self-referential and collective non-self-referential processing at these stages. In addition, at the late P3 stage (350–600 ms), larger P3 amplitudes were also elicited by individual self-referential than by individual non-self-referential processing during 350–600 ms interval. However, the collective self-reference effect, indicated by the differences between collective self-referential and collective non-self-referential processing, did not appear until 450 ms and extended to 600 ms. Moreover, individual self-reference effect was more pronounced than collective self-reference effect in the 350–500 ms interval, whereas individual and collective self-reference effect had no significant difference in the 500–600 ms interval. These findings indicated that the time courses of neural activities were different in processing individual and collective self.

Influence of collective self-esteem on individual and collective self-referential processing: An ERP study

Previous studies have demonstrated that self-relevant information is processed more quickly and deeply than other information, and that self-esteem could modulate the self-reference effect. Individuals with low self-esteem were shown to be more sensitive to self-related information than other information that were individuals with high self-esteem. However, these studies mainly focused on self-esteem and self at the individual level, ignoring them at the collective level. The present study aimed to determine whether collective self-esteem could modulate individual and collective self-referential processing. Collective self-esteem is associated with one’s evaluation of the group he belongs to, and it emphasizes social relationships and collective value. We hypothesized that, similar to individual self-esteem, collective self-esteem may also influence self-referential processing, especially concerning the collective. More specifically, individuals with low collective self-esteem may be more sensitive to collective self-referential processing than individuals with high collective self-esteem. In order to explore the time course of self-referential processing, event-related potentials (ERPs) were recorded while participants performed a self-reference task in which they were presented with positive and negative personality trait adjectives and required to make judgements on themselves or a famous person, either Chinese or American. Participants’ own names were selected as the individual self-relevant stimuli, while Andy Lau, a famous Chinese superstar, was chosen as the individual non-self-relevant stimulus. It was considered that collective self emphasized the identity as a member of a social group. Thus, “中国人(Chinese person)” and “美国人(American person)”, were chosen as the collective self-relevant and non-self-relevant stimuli. Results showed an obvious modulation effect of collective self-esteem on the N1, P2 and P3 components in collective self-referential processing. For the early N1 component, larger N1 amplitudes were elicited by collective self-referential than collective non-self-referential processing in individuals with high collective self-esteem, whereas no such difference was observed in individuals with low collective self-esteem. For the later P2 and P3 components, larger P2 and P3 amplitudes were elicited by collective self-referential than collective non-self-referential processing in individuals with low collective self-esteem, whereas no such difference was observed in individuals with high collective self-esteem. Although an obvious individual self-referential effect was also observed in both low and high collective self-esteem individuals, the strength of the individual self-reference effect, indicated by the difference between individual self-referential and individual non-self-referential conditions, showed no significant difference between these two groups. Consistent with previous studies, the individual self was the core of self-concept and the individual self-reference effect was robust. Moreover, individual and collective self-esteem, two different aspects of self-esteem, cannot be equated. In conclusion, the present study indicated that collective self-esteem could modulate collective rather than individual self-referential processing.

Internet-word compared with daily-word priming reduces attentional scope.

This study tested whether one aspect of cognitive processing, namely visual attentional scope, was more narrow in an Internet environment compared to a daily-life environment. Words related to the Internet and words related to daily life were used as priming stimuli before participants had to respond to a Navon letter to assess attention to global vs. local targets. In Experiment 1, reaction time during the Navon task showed that global processing priority was greater after daily words than after Internet words. In Experiment 2, ERP data showed significantly larger P2 amplitudes induced by global letters than local letters in the two conditions. After Internet-word priming, a smaller N2 amplitude was induced by local letters than by global letters, but this difference was not observed after daily-word priming. The influence of priming on attentional scope might have occurred at the stage of cognitive control, indicating that it was easier to resist the interfering effect of global letters in the Internet-word condition than in the daily-word condition. The results of both experiments suggest that attentional scope is narrower in an Internet environment than in a daily-life environment.