Event-related Potential Study Research Articles

Does cognitive control mediate the relationship between peer presence and adolescent risk-taking? An ERP study.

Peer presence influences risk-taking behavior, particularly in adolescence. Based on the dual system model, this event-related potential study examined whether and how the presence of a peer displayed a preference for risky behavior would increase adolescents' risk-taking by disrupting their cognitive control processes in either emotional or non-emotional contexts. A sample of 106 adolescents (17-19 years of age) completed two Stoop tasks and a Balloon Analog Risk Task under three peer presence conditions. Results revealed that compared to other conditions, the presence of a risk-averse peer caused adolescents to make safer decisions through improving their conflict monitoring (more negative N200-diff), whereas a risk-preference peer's presence led adolescents to more risky decisions through disrupting their conflict resolution (more positive N450-diff) but they were only observed on the Emotional Stroop task. These findings suggest that different peer presence contexts could increase or decrease adolescents' risk-taking behaviors by influencing their cognitive control under an emotional context rather than in a non-emotional context.

Threatening an Illusory Limb: An Event-related Potential Study of the Rubber Hand Illusion.

The rubber hand illusion (RHI) is a well-established method for studying body ownership: Given adequate concordance of visual, sensory, and proprioceptive stimuli, the individual experiences a rubber hand as his or her own. To study the effects of a threat to the rubber hand. We created a typical RHI paradigm but added threatening pain: Both the real hand of an individual and the rubber hand were stroked with a brush, either synchronously (RHI-inducing condition) or asynchronously (control condition), but only the rubber hand was then pricked with a needle to create a threatening pain condition. Event-related potentials (ERPs) were recorded in a group of 23 typically-developed individuals. ERP effects were source-localized using low-resolution electromagnetic tomography. The individuals consistently reported experience of the RHI during the experiment when the brush strokes were applied synchronously to both the real hand and the rubber hand. ERP analysis revealed that synchronous brush stroking gave rise to higher amplitude of frontal ERPs in the 100-200 ms range than asynchronous brush stroking, which was interpreted as reflecting the RHI. In the threatening pain condition, ERPs showed a greater positivity at frontocentral electrodes, source localized in the supplementary motor area (SMA). SMA activation could reflect a control mechanism over reflexive motor activity, facilitating a possible threat-related response. Further studies should address ERP effects and the extent of the RHI to standard and threat stimuli in a correlative fashion to further elucidate the functional significance of the neurophysiological findings.

N2 component implied a subjective conflict detection thinking strategy: an event-related potential study of the covariation detection task

N2 component implied a subjective conflict detection thinking strategy: an event-related potential study of the covariation detection task

Differences in attentional bias between self-related information and external cues from others in individuals with social anxiety: An event-related potential study

Individuals with high social anxiety show a more considerable attentional bias toward self-relevant information and outwardly threatening stimuli than do those with low social anxiety. Some studies have investigated the attentional bias between self-relevant information and external social cues in people with high social anxiety but have not reached consistent conclusions. This study used a modified dot-probe task and collected temporal and electroencephalogram responses to three self-other face pairs among 15 people with high social anxiety and 20 people with low social anxiety. Both groups responded quicker to self-relevant information than external social cues. Others’ emotional potencies moderated the attentional bias. Individuals with high social anxiety exhibited larger P1 amplitudes and smaller N170 amplitudes (mainly in the right hemisphere) for all face pairs and larger P2 amplitudes for the self-neutral and other-angry face pairs than those with low social anxiety. These findings suggest that people with social anxiety prioritize allocating attentional resources to self-relevant information, with others’ angry faces having the greatest influence on the allocation. Individuals with high social anxiety initially exhibit more attentional vigilance and less structural coding for face pairs, followed by heightened engagement with threatening cues compared to those with low social anxiety.

Processing of Counterfactual Conditional Sentences with Differential Propositional Truth-Value in Mandarin Chinese: Evidence from ERP

Although many studies document the role of propositional truth-value in human psychological reading behavior, there is a relative paucity of research examining the role of differential propositional truth-value in processing Chinese counterfactual conditionals. This study is to investigate the role of differential propositional value in processing Chinese counterfactual conditionals by means of ERPs (event-related potentials). The study is based on comprehending two types of Chinese counterfactual conditionals, which is propositional truth value introduced by two different markers of conditional conjunctions in the protasis and apodosis, such as true counterfactual conditional markers jiaru (if) & jiu (so) in the sentence wo xiang yu jiaru you tui jiu keyi zai shuixia zhixi (I think if fish had legs so they could stifle under water), and false counterfactual conditional markers ruguo (if) & namo (then) in the sentence wo xiang gou ruguo you lin namo keyi zai shuixia huxi (I think if dogs had scales, then they could breathe under water). Two counterfactual propositional values (i.e. true and false propositional values) are constructed through manipulating sentence counterfactuality between the true and false counterfactual conditional markers in the protasis and the apodosis. Twenty-four full-time Chinese college students participated in the ERP study. The results demonstrated that processing the true counterfactual propositional sentences with conditional markers jiaru (if) & jiu (so) elicited the N400 effect relative to false propositional sentences with conditional markers ruguo (if) & namo (then). Moreover, the counterfactual sentences with true propositional conditions varied from the elicitation of the N400 effect in the protasis and absence of the N400 effect in the apodosis, showing that semantic roles may gradually disappear under the impact of truth value of propositional counterfactual condition, and/or the roles of semantic anomaly was eliminated in the accumulated sentence processing. While for the false counterfactual conditional sentences, elicitations of P300 in the protasis and robust N400 effect in the apodosis were shown, indicating the increasing semantic role in the processing. Interestingly, there was the absence of the P600 effect for processing sentences with syntactic violation, suggesting little extra syntactic cost in processing sentences with false propositional condition.

Event-related potentials study on the effects of high neuroticism on senile false memory.

To study the false memory among senile normal people with high neuroticism and low neuroticism using neuropsychological scales and event-related potentials (ERPs), and to explore the effects of high neuroticism on false memory and its neuroelectrophysiological mechanism. A cross-sectional study was conducted, in which the general situation questionnaire, adult version of Eysenck personality questionnaire (EPQ) and Montreal cognitive assessment (MoCA) scale were used to establish a multi-dimensional survey in senile normal people over 60 years old from communities in Zhengzhou, and the EPQ and general situation questionnaire were used to comprehensively screen and divide the study subjects into high neuroticism group and low neuroticism group from 206 senile people. The population was matched by 1:1 according to gender, age (±2 years), and years of education (±2 years), and 40 subjects were finally enrolled for detection of electroencephalograph (EEG) components using ERPs. The Deese-Roediger-McDermott (DRM) paradigm of false memory was designed using E-prime2.0 system, and the stimulus program was presented. The EEG signals of the study subjects were recorded in real time and acquired using 64-channel Neuroscan EEG signals acquisition system. High neuroticism group was evidently lower in the mean accuracy than low neuroticism group, and the difference in the mean accuracy was statistically significant (P = 0.013), but the difference in reaction time was not statistically significant. 2. The mean amplitude of EEG component N400: The difference in the main effect of N400 in the brain region was significantly different (P<0.001), and the mean amplitude of N400 was the largest in frontal region, followed by central region and parietal region successively (all P<0.05). There was no statistically significant difference in the neurotic main effect or the interaction effect of neuroticism and brain region. The latency of N400: There was no significant difference in the neurotic main effect, main effect of the brain region or the interaction effect of neuroticism and brain region. 3. The mean amplitude of EEG component LPC: The difference in the main effect of the brain region was significantly different (P<0.001), and the mean amplitude of LPC was the largest in frontal region, followed by central region and parietal region successively (all P<0.05). There was no significant difference in the neurotic main effect, neuroticism or the interaction effect of neuroticism and brain region. As to the latency of LPC, there was significant difference in the main effect of the brain region (P = 0.025), and the latency of LPC was shorter in frontal region than that in central region (P<0.05). The differences in the neurotic main effect, interaction effect of neuroticism and brain region were not statistically significant. High neuroticism can significantly increase the false memory of senile normal people. The EEG components N400 and LPC are potential early indicators of high neuroticism affecting false memory. High neuroticism may influence false memory by affecting the frontal cortex function.

Effects of daily listening to 6 Hz binaural beats over one month: an event-related potentials study

The aim of the present study was to identify cognitive alterations, as indicated by event-related potentials (ERPs), after one month of daily exposure to theta binaural beats (BBs) for 10 minutes. The recruited healthy subjects (n = 60) were equally divided into experimental and control groups. For a month, the experimental group was required to practice BBs listening daily, while the control group did not. ERPs were assessed at three separate visits over a span of one month, with a two-week interval between each visit. At each visit, ERPs were measured before and after listening. The auditory and visual ERPs significantly increased the auditory and visual P300 amplitudes consistently at each visit. BBs enhanced the auditory N200 amplitude consistently across all visits, but the visual N200 amplitude increased only at the second and third visits. Compared to the healthy controls, daily exposure to BBs for two weeks resulted in increased auditory P300 amplitude. Additionally, four weeks of BBs exposure not only increased auditory P300 amplitude but also reduced P300 latency. These preliminary findings suggest that listening to BBs at 6 Hz for 10 minutes daily may enhance certain aspects of cognitive function. However, further research is needed to confirm these effects and to understand the underlying mechanisms. Identifying the optimal duration and practice of listening to 6 Hz BBs could potentially contribute to cognitive enhancement strategies in healthy individuals.

Unravelling the origin of the reward positivity: a human intracranial event-related brain potential study.

The reward positivity (RewP) is an event-related brain potential (ERP) component that emerges approximately 250 to 350 milliseconds (ms) after receiving reward-related feedback stimuli and is believed to be important for reinforcement learning and reward processing. Although numerous localization studies have indicated that the anterior cingulate cortex (ACC) is the neural generator of this component, other studies have identified sources outside of the ACC, fuelling a debate about its origin. Because the results of EEG and MEG source localization studies are severely limited by the inverse problem, we addressed this question by leveraging the high spatial and temporal resolution of intracranial EEG. We predicted that we would identify a neural generator of the RewP in the caudal ACC. We recorded intracranial EEG in 19 refractory epilepsy patients who underwent invasive video-EEG monitoring at Ghent University Hospital, Belgium. Participants engaged in the virtual T-maze task (vTMT), a trial-and-error task known to elicit a canonical RewP, while scalp and intracranial EEG were simultaneously recorded. The RewP was identified using a difference wave approach for both scalp and intracranial EEG. The data were aggregated across participants to create a virtual "meta-participant" that contained all the recorded intracranial ERPs (iERPs) with respect to their intracranial contact locations. We used both a hypothesis-driven (focused on ACC) and exploratory (whole-brain analysis) approach to segment the brain into regions of interest (ROI). For each ROI, we evaluated the degree to which the time course of the absolute current density (ACD) activity mirrored the time course of the RewP, and confirmed the statistical significance of the results using permutation analysis. The grand average waveform of the scalp data revealed a RewP at 309 ms after reward feedback with a frontocentral scalp distribution, consistent with the identification of this component as the RewP. The meta-participant contained iERPs recorded from 582 intracranial contacts in total. The ACD activity of the aggregated iERPs were most similar to the RewP in left caudal ACC, left dorsolateral prefrontal cortex, left frontomedial cortex, and left white matter, with the highest score attributed to caudal ACC, as predicted. To our knowledge, this is the first study that uses intracranial EEG aggregated across multiple human epilepsy patients and current source density analysis to identify the neural generator(s) of the RewP. These results provide direct evidence that the ACC is a neural generator of the RewP.

Neurophysiological Correlates of Near-Wins in Gambling: A Systematic Literature Review.

Identification of specific patterns of brain activity related to problem gambling may provide a deeper understanding of its underlying mechanisms, highlighting the importance of neurophysiological studies to better understand development and persistence of gambling behavior. The patterns of cognitive functioning have been investigated through electroencephalography (EEG) studies based on the near-win/near-miss (NW) effect. The main goal of the present study was to evaluate the neurophysiological basis of NWs and their modulation by gambling problems through a systematic review of event-related potentials (ERP) studies elicited by feedback events. The review followed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA). A total of 15 studies were included, 12 comprising non-problem gamblers (NPGs) and three comparing problem gamblers (PGs) with matched controls. For the P300 component, the win outcome elicited a larger amplitude than the other outcomes (NW and loss), followed by the NW outcome, which elicited a larger amplitude than loss in some studies. For feedback-related negativity (FRN), the loss outcome evoked a more negative amplitude in several studies, despite eliciting a similar amplitude to NW outcomes in others. For PGs, the NW outcome evoked a higher amplitude of P300 than loss, while NPGs showed a similar amplitude to both outcomes. The present review gathered information from different sources and provides a consistent view of the different studies. However, studies lack systematic and robust methodologies, leading to inconsistent results and making it difficult to reach any definitive conclusions.

Are Deaf College Students More Sensitive to Unfair Information? Evidence from an ERP Study.

To better understand the individual differences in fairness, we used event-related potentials (ERPs) to explore the fairness characteristics of deaf college students through the ultimatum game task. Behaviorally, the significant main effect of the proposal type was found, which meant both deaf and hearing college students showed a lower acceptance rate for the more unfair proposal. Interestingly, we found a significant interaction between group and proposal type in the early stage (N1). Moreover, in the deaf college group, N1 (induced by moderately and very unfair proposals) was significantly larger than that of fair proposals. However, we found that deaf college students had smaller amplitudes on P2 and P3 than hearing college students. These results suggested that deaf college students might pursue more equity strongly so they are more sensitive to unfair information in the early stage. In a word, we should provide more fair allocations for deaf college students in our harmonious society.

Perceptual anchoring: Children with dyslexia benefit less than controls from contextual repetitions in speech processing

ObjectivesIndividuals with dyslexia perceive and utilize statistical features in the auditory input deficiently. The present study investigates whether affected children also benefit less from repeating context tones as perceptual anchors for subsequent speech processing. MethodsIn an event-related potential study, eleven-year-old children with dyslexia (n = 21) and without dyslexia (n = 20) heard syllable pairs, with the first syllable either receiving a constant pitch (anchor) or variable pitch (no-anchor), while second syllables were identical across conditions. ResultsChildren with and without dyslexia showed smaller auditory P2 responses to constant-pitch versus variable-pitch first syllables, while only control children additionally showed smaller N1 and faster P1 responses. This suggests less automatic processing of anchor repetitions in dyslexia. For the second syllables, both groups showed faster P2 responses following anchor than no-anchor first syllables, but only controls additionally showed smaller P2 responses. ConclusionsChildren with and without dyslexia show differences in anchor effects. While both groups seem to allocate less attention to speech stimuli after contextual repetitions, children with dyslexia display less facilitation in speech processing from acoustic anchors. SignificanceAltered anchoring in the linguistic domain may contribute to the difficulties of individuals with dyslexia in establishing long-term representations of speech.

Impaired inhibitory control when processing real but not cartoon emotional faces in autistic children: Evidence from an event-related potential study.

Impaired socioemotional functioning characterizes autistic children, but does weak inhibition control underlie their socioemotional difficulty? This study addressed this question by examining whether and, if so, how inhibition control is affected by face realism and emotional valence in school-age autistic and neurotypical children. Fifty-two autistic and 52 age-matched neurotypical controls aged 10-12 years completed real and cartoon emotional face Go/Nogo tasks while event-related potentials (ERPs) were recorded. The analyses of inhibition-emotion components (i.e., N2, P3, and LPP) and a face-specific N170 revealed that autistic children elicited greater N2 while inhibiting Nogo trials and greater P3/LPP and late LPP for real but not cartoon emotional faces. Moreover, autistic children exhibited a reduced N170 to real face emotions only. Furthermore, correlation results showed that better behavioral inhibition and emotion recognition in autistic children were associated with a reduced N170. These findings suggest that neural mechanisms of inhibitory control in autistic children are less efficient and more disrupted during real face processing, which may affect their age-appropriate socio-emotional development.

Maternal emotion regulation abilities affect adolescent depressive symptoms by mediating their emotion regulation ability: An ERP study

Adolescents with major depressive disorder (MDD) experience significant difficulties in emotion regulation. This study aimed to explore emotion regulation in adolescents with depression using an emotion regulation paradigm combined with event-related potentials (ERP) while investigating the relationship between maternal emotion regulation and adolescent depressive symptoms through a mediation model. Overall, 38 healthy controls (HC) and 57 adolescents with depression (MDD) rated the pictures they saw according to aversive reappraisal (reappraisal of an aversive picture or down-regulate aversive emotions), aversive watch, and neutral conditions. Adolescents with depression gave more negative ratings to aversive images, and the emotional regulation success index (ERSI) of adolescents with depression was lower than that of healthy individuals. ERP data revealed an elevation in late positive potential (LPP) amplitude during the aversive reappraisal and aversive watch conditions compared with that in the neutral condition in the MDD group. Compared with the HC group, adolescents with depression showed larger LPP amplitudes under aversive watch conditions. The aversive reappraisal condition evoked a larger LPP than that in the other conditions in the HC group in the late time windows. The ΔLPP (separating the variability in the ERP wave associated with emotion regulation) was larger in the HC group than in the MDD group. Mediation analysis revealed that maternal emotion regulation influenced adolescent depression levels through its effect on the adolescent’s emotion regulation. These findings provide important insights into the emotion regulation process in adolescents with depression and offer suggestions for clinical interventions.

High Neural Efficiency in Unconscious Perceptual Processing among Table Tennis Athletes: An Event-Related Potential Study.

Neural efficiency refers to the brain's ability to function with reduced resource expenditure while maintaining high performance levels. Previous research has demonstrated that table tennis athletes have greater neural efficiency at the conscious level. However, it is unknown whether they exhibit greater neural efficiency at the unconscious level. Therefore, this study aims to investigate unconscious perceptual processing and neural efficiency in elite table tennis athletes through tasks involving the judgment of spin serves. Fifty healthy, right-handed individuals participated in this study, including 25 elite table tennis athletes and 25 control participants without professional training experience. To evaluate the unconscious perceptual characteristics of both groups, we used a combination of masked priming paradigm and event-related potential techniques. The behavioral results reveal that, compared to the control group, the table tennis athletes displayed reduced reaction times (p < 0.001) and increased priming effects (p < 0.001) under unconscious conditions. The electrophysiological findings indicated that both groups elicited N1, N2, and P2 components. Notably, compared to the control group, the table tennis athletes exhibited significantly lower amplitude responses at the occipital lobe electrodes PO3, POz, PO4, O1, Oz, and O2 (p < 0.001). These results further support the neural efficiency hypothesis, indicating that prolonged professional training enhances athletes' capacities for specialized unconscious cognitive processing.

High- and low-social-anxiety individuals process the outcomes of ability comparisons differently: an event-related potential study.

Individuals engage in upward or downward comparisons with superiors or inferiors, respectively. Social comparison is associated with social anxiety. Utilizing event-related potentials, we investigated how individuals with high social anxiety (HSA) and low social anxiety (LSA) evaluate self- versus other-outcomes in upward and downward comparison contexts. We found significant valence effects of self- or other-outcomes on feedback-related negativity (FRN) and P300 for both groups, with loss inducing larger FRN and smaller P300 than gain. In the early stage, the valence effect of other-outcomes was significant when LSA participants gained money, but not when they lost money, revealing a social comparison effect on FRN. Conversely, this valence effect was significant whether HSA participants gained or lost money. At the late stage, the valence effect of other-outcomes was significant when HSA or LSA participants gained money but not when they lost, revealing social comparison effects on the P300. Notably, only the social comparison effect in the LSA group was further moderated by comparison direction. These findings suggest that LSA participants engaged in social comparison throughout all evaluation stages, whereas HSA participants started at the late stage. Moreover, LSA participants were more sensitive to different comparison directions in the late stage.

The Roles of Segments and Tone in Mandarin Lexical Processing: An ERP Study.

Segments and tone are important sub-syllabic units that play large roles in lexical processing in tonal languages. However, their roles in lexical processing remain unclear, and the event-related potential (ERP) technique will benefit the exploration of the cognitive mechanism in lexical processing. The high temporal resolution of ERP enables the technique to interpret rapidly changing spoken language performances. The present ERP study examined the different roles of segments and tone in Mandarin Chinese lexical processing. An auditory priming experiment was designed that included five types of priming stimuli: consonant mismatch, vowel mismatch, tone mismatch, unrelated mismatch, and identity. Participants were asked to judge whether the target of the prime-target pair was a real Mandarin disyllabic word or not. Behavioral results including reaction time and response accuracy and ERP results were collected. Results were different from those of previous studies that showed the dominant role of consonants in lexical access in mainly non-tonal languages like English. Our results showed that consonants and vowels play comparable roles, whereas tone plays a less important role than do consonants and vowels in lexical processing in Mandarin. These results have implications for understanding the brain mechanisms in lexical processing of tonal languages.

A machine learning artefact detection method for single-channel infant event-related potential studies

Objective. Automated detection of artefact in stimulus-evoked electroencephalographic (EEG) data recorded in neonates will improve the reproducibility and speed of analysis in clinical research compared with manual identification of artefact. Some studies use very short, single-channel epochs of EEG data with little recorded EEG per infant—for example because the clinical vulnerability of the infants limits access for recording. Current artefact-detection methods that perform well on adult data and resting-state and multi-channel data in infants are not suitable for this application. The aim of this study was to create and test an automated method of detecting artefact in single-channel 1500 ms epochs of infant EEG. Approach. A total of 410 epochs of EEG were used, collected from 160 infants of 28–43 weeks postmenstrual age. This dataset—which was balanced to include epochs of background activity and responses to visual, auditory, tactile and noxious stimuli—was presented to seven independent raters, who independently labelled the epochs according to whether or not they were able to visually identify artefacts. The data was split into a training set (340 epochs) and an independent test set (70 epochs). A random forest model was trained to identify epochs as either artefact or not artefact. Main results. This model performs well, achieving a balanced accuracy of 0.81, which is as good as manual review of data. Accuracy was not significantly related to the infant age or type of stimulus. Significance. This method provides an objective tool for automated artefact rejection for short epoch, single-channel EEG in neonates and could increase the utility of EEG in neonates in both the clinical and research setting.

The association between insomnia symptoms and cognitive flexibility among undergraduates: An event-related potential study

ObjectiveTo explore the association between insomnia symptoms and cognitive flexibility among undergraduates, along with its potential neural mechanisms. MethodA total of 102 participants were divided into insomnia (n = 55) and control (n = 47) groups based on sleep status. Cognitive flexibility was assessed using the Cognitive Flexibility Inventory (CFI) and the Number-Letter Task (N-L task). EEG data were recorded during the N-L task. ResultsThe insomnia group exhibited lower CFI scores and higher switch costs in reaction time and accuracy compared to the control group. ERP analysis showed differences in P2, N2, and P3 component amplitudes between the two groups, with reduced N2 amplitude in the insomnia group under repeat trials. Time-frequency analysis revealed larger theta band event related synchronization in the frontal region and smaller theta band ERS in the parietal region under switch trials in the control group; the alpha band event-related desynchronization in the parietal region under repeat trials was significantly smaller in the control group compared to switch trials. ConclusionCompared to undergraduates with normal sleep, those with insomnia symptoms exhibited reduced cognitive flexibility, which may be associated with some alterations in brain electrophysiological activities.

Attentional resource consumption of verbal-humor processing: An ERP study

As a high-demanding mental activity with both cognitive and emotional factors, verbal-humor processing consumes more attentional resources than non-humor processing, which has been demonstrated by behavioral studies, but little has been examined at a real-time scale. Based on the three-stage model (incongruity detection, incongruity resolution, and mirth), the current study used event-related potential (ERP) and event-related oscillation (ERO) to explore the attentional resource consumption of verbal-humor processing by employing a dual-task paradigm in which sentence comprehension (humorous, positive, neutral) was the primary task and arithmetical calculation (simple, difficult) was the secondary task.Participants’ (N=38) behavioral performance and ERP/ERO measures in two tasks were analyzed. ERP results of verbal-humor processing revealed significantly larger LAN, LLAN, and LPP activation, which indexed three stages. ERO results showed significant beta power changes in the detection stage and theta changes in the resolution and mirth stages. The behavioral data indicated that the Reaction Times (RTs) of the arithmetical task following verbal-humor processing were longer than those following non-humorous positive and neutral ones. The ERP results of arithmetical calculation found that the calculations following verbal-humor processing elicited significantly greater P2, P3b, and positive slow wave amplitudes than those following the other two processings, which reflected more resource allocation in the calculation to compensate for the resource preemption of verbal-humor processing. In addition, the calculation following positive sentence exhibited a greater ERP amplitude in the relatively early P2 time intervals than that following the neutral sentences. Collectively, the behavioral, ERP, and ERO results concurrently confirmed that verbal-humor processing consumed more attentional resources compared with non-humorous counterparts, and moreover, the comparison of ERP following humorous and positive sentences suggested that the processing of the cognitive factor consumes more attentional resources than the emotional factor although both factors play a role in the process.

Ill-defined constructs in SLA research using event-related potentials

An emerging trend in Second Language Acquisition (SLA) research is that proficiency is more important than the age of acquisition (AoA) to account for L2 ultimate attainment. An increasing number of researchers play down the role – or in some cases even deny the very existence – of a critical period (or ‘window of sensitivity’) and state that learners’ proficiency – and its various determinants – may trump age. There is a serious methodological issue with such a stance though. While AoA is easily factorised consistently across most experimental studies, participants’ proficiency is not. Authors of Event-Related Potentials (ERP) studies in particular are extremely vague and discordant as to how they rate participants’ proficiency. This makes the construct ‘proficiency’ unreliable, the results of ERP studies hard to compare, and the claims based on the primacy of proficiency in respect to AoA much weaker. This paper suggests more caution in general and in particular the need for collaboration between neurolinguists and SLA experts in the field of foreign language teaching and testing.