Late Positive Component Research Articles

Neural Correlate Differences in Number Sense Between Children With Low and Middle/High Socioeconomic Status.

Although some cognitive studies provided reasons that children with low socioeconomic status (SES) showed poor mathematical achievements, there was no explicit evidence to directly explain the root of lagged performance in children with low SES. Therefore, the present study explored the differences in neural correlates in the process of symbolic magnitude comparison between children with different SESs by the event-related potentials (ERPs). A total of 16 second-graders from low-SES families and 16 from middle/high-SES families participated in this study. According to the results of anterior N1 (early attention) and P2 (extraction of numerical meaning) over the frontal region, the differences among children with different SESs were manifested as differences in general neural activities in terms of attention and top-down cognitive control. In the late stage of cognitive processing, there was no significant difference in the average amplitude of the late positive component (LPC) between children with different SES, indicating that low SES did not influence the information encoding and memory updating of numerical representation, which was responsible by the parietal lobe. The educational implications of this study are mentioned in the discussion.

Dynamic versus static indicators of threat: N2 and LPC modulation index attack intent and biological relevance during an affective Flanker task

Biological relevance may influence the neural response towards images which depict attack intent. In the present study, images featuring reptiles and firearms were employed as target and flanking stimuli in a modified version of the affective Flanker task. Forty-two participants (21 male) completed the modified Flanker task as EEG was recorded. Congruency effects in reaction times were more consistently observed for arrays with firearm targets than for arrays with reptile targets. Arrays with neutral targets (i.e., water pistols, turtles) evoked more negative mean N2 (250–400 ms) amplitudes than those with attack targets (i.e., attacking snakes, aimed handguns), while arrays with aimed handgun targets elicited more positive mean activity for the late positive component (LPC; 450-650 ms) compared to arrays with water pistol or reptile targets. Congruency effects were also found in N2 activity for arrays with firearm targets and reptile Flankers. In addition, LPC amplitude for incongruent arrays with attack targets and neutral Flankers was reduced compared to congruent attack arrays. These findings suggest that biological relevance influences interference processing (the N2) and intersects with attack intent during the later stages of picture processing (the LPC).

Measuring the influence of phonological neighborhood on visual word recognition with the N400: Evidence for semantic scaffolding

Research in visual word recognition has shown that phonological neighborhood density facilitates visual word recognition. The current research was designed to determine the electrophysiological effect of phonological neighborhood density (PND). In two experiments, participants made lexical decisions to words varying on phonological neighborhood while Event-related Potentials (ERPs) were recorded. Behaviorally, the results replicate previous research by showing that words with many phonological neighbors were responded to more rapidly than were words with few phonological neighbors. However, the main contribution of the current research is that it shows an effect of PND on the N400 and Late Positive Component Event-Related Potentials. In contrast to previous reports in the literature, the nature of the effect was such that the N400 was larger to words with few phonological neighbors than to words with many. Experiment 2 replicated these findings and provided estimates of the independent components’ time course and source localization. The increased N400 for small neighborhood words is thought to reflect additional semantic processing required for these words due their weaker phonological representations.

Emotion anticipation induces emotion effects in neutral words during sentence reading: Evidence from event-related potentials

This study examined whether emotion responses during reading are co-constituted by lexical items and the preceding context. Event-related potentials to coherent emotion and neutral words finishing sentences with or without strong constraint for the incoming valence were analyzed. Typical frontal P200 and posterior late positive component (LPC) emotion responses were seen to emotion words relative to neutral words in the neutral context, indicating heightened attention allocation and further valence analysis induced by word-level emotionality. With emotional bias in the context, words elicited reduced N400 responses, indicating facilitated semantic processing. Critically, we obtained evidence for contextualized emotion responses during coherent sentence comprehension. With active anticipation of the incoming emotionality (evidenced by the frontal positivity to plausible emotionally unpredicted words), enhanced P200 and LPC responses were seen to neutral words in emotional contexts. These findings demonstrated that, like word emotionality, emotion-constraining contexts could similarly engage motivational circuits and attention resources, affecting early perception and later further affective evaluation of the incoming information, even for emotionally neutral words. Despite the seeming similarity, multiple routes may be involved for giving rise to these neurophysiological reactions during emotion processing - while lexically driven LPCs were significantly correlated with empathy, contextually driven LPCs were not. Together, these findings provide support for contextualized emotion responses during congruent sentence reading when explicit emotional judgment on the materials is not required. These findings also provide an initial understanding about how these responses are mediated by empathy - an important aspect of human ability to perceive emotion.

Part-List Cues Hinder Familiarity but Not Recollection in Item Recognition: Behavioral and Event-Related Potential Evidence.

Participants’ memory performance is normally poorer when a subset of previously learned items is provided as retrieval cues than none of the retrieval cues is provided. This phenomenon is called the part-list cuing effect, which has been discovered in numerous behavioral studies. However, there is currently no relevant behavioral or event-related potential (ERP) research to investigate whether the forgetting effect caused by part-list cues is more sensitive to recollection or to familiarity. By combining the part-list cuing paradigm with the Remember/Know procedure, we investigated this issue in the present ERP study. Behavioral data showed part-list cuing induced detrimental effect in two aspects: significantly lowered familiarity of the target items and decreased memory discrimination score (Pr score) for “Know” but not for “Remember” items in the part-list cue condition than in the no-part-list cue condition. ERP data revealed that the FN400 old/new effects, which are associated with familiarity, were absent when providing part-list cues, whereas the late positive complex (LPC) old/new effects, which are associated with recollection, were observed comparably in both part-list cue and no-part-list cue conditions. Converging behavioral and ERP results suggested that part-list cues hindered familiarity-based retrieval but not recollection-based retrieval of item recognition. Theoretical implications of the findings for the part-list cuing effect are discussed.

Am I the same person across my life span? An event-related brain potentials study of the temporal perspective in self-identity.

While self-identity recognition has been largely explored, less is known on how self-identity changes as a function of time. The present work aims to explore the influence of the temporal perspective on self-identity by studying event-related brain potentials (ERP) associated with face processing. To this purpose, participants had to perform a recognition task in two blocks with different task demands: (i) identity recognition (self, close-friend, unknown), and (ii) life stage recognition (adulthood -current-, adolescence, and childhood). The results showed that the N170 component was sensitive to changes in the global face configuration when comparing adulthood with other life stages. The N250 was the earliest neural marker discriminating self from other identities and may be related to a preferential deployment of attentional resources to recognize own face. The P3 was a robust index of self-specificity, reflecting stimulus categorization and presumably adding an emotional value. The results of interest emerged for the subsequent late positive complex (LPC). The larger amplitude for the LPC to the self-face was probably associated with further personal significance. The LPC, therefore, was able to distinguish the continuity of the self over time (i.e., between current self and past selves). Likewise, this component also could discriminate, at each life stage, the self-identity from other identities (e.g., between past self and past close-friend). This would confirm a remarkable role of the LPC reflecting higher self-relevance processes. Taken together, the neural representation of oneself (i.e., "I am myself") seems to be stable and also updated across time.

Exploring the Event-Related Potentials' Time Course of Associative Recognition in Autism.

Behavioral data on episodic recollection in autism spectrum disorders (ASD) point limited relational memory functioning. However, the involvement of successive memory processes in the profile of episodic memory in ASD needs more study. Here, we used event-related potentials (ERP) to investigate the time course of episodic recollection with an associative recognition paradigm with picture pairs. Twenty-two participants with ASD and 32 with typical development (TD), all right-handed, were included. Behavioral results confirmed difficulties in correctly recognizing identical pairs in the ASD relative to TD group. We found an unexpected amplitude decrement on the P2 (220-270 msec) and FN400 (350-470 msec) potentials, suggesting diminished priming and familiarity effects in the ASD relative to TD group. However, ERP data revealed that the recognition of associative information relies on the same electrophysiological process (old/new effect in the 600-700-msec late positive component) in ASD participants as in TD ones, with a parietal extension in the ASD group. These results suggest that the electrophysiological processes of associative recognition are qualitatively similar in individuals with and without ASD but may differ quantitatively. This difference may be driven by the reduced early processing of picture pairs that may in turn lead to their diminished integration into the semantic memory system, being partially compensated by a greater involvement of associative memory during the recollection process. Other studies would be useful to go further in identifying these cognitive processes involved in atypical recognition in ASD and their neural substrates. Autism Res 2020, 13: 1998-2016. © 2020 International Society for Autism Research and Wiley Periodicals LLC LAY SUMMARY: We identified diminished performance on the associative recognition of picture pairs in adolescents and young adults with autism when compared to typical development. Electrophysiological data revealed qualitative similarities but quantitative differences between-group, with diminished priming and familiarity processes partially compensated by an enhanced parietal recollection process.

Are All Code-Switches Processed Alike? Examining Semantic v. Language Unexpectancy

Prior studies using the event-related potential (ERP) technique show that integrating sentential code-switches during online processing leads to a broadly distributed late positivity component (LPC), while processing semantically unexpected continuations instead leads to the emergence of an N400 effect. While the N400 is generally assumed to index lexico-semantic processing, the LPC has two different interpretations. One account suggests that it reflects the processing of an improbable or unexpected event, while an alternative account proposes sentence-level reanalysis. To investigate the relative costs of semantic to language-based unexpectancies (i.e., code-switches), the current study tests 24 Spanish-English bilinguals in an ERP reading study. Semantically constrained Spanish frames either varied in their semantic expectancy (high vs. low expectancy) and/or their language continuation (same-language vs. code-switch) while participants’ electrophysiological responses were recorded. The Spanish-to-English switch direction provides a more naturalistic test for integration costs to code-switching as it better approximates the code-switching practices of the target population. Analyses across three time windows show a main effect for semantic expectancy in the N400 time window and a main effect for code-switching in the LPC time window. Additional analyses based on the self-reported code-switching experience of the participants suggest an early positivity linked to less experience with code-switching. The results highlight that not all code-switches lead to similar integration costs and that prior experience with code-switching is an important additional factor that modulates online processing.

Cognitive processes during deception about attitudes revisited: a replication study.

Event-related potential (ERP) studies about deception often apply recognition tasks. It remains questionable whether reported ERP patterns and cognitive processes can be generalized to other contexts. As the study by Johnson et al. (2008) fills this gap by investigating deception regarding attitudes, we tried to replicate it. Participants (N = 99) were instructed to lie or tell the truth about their attitudes. We obtained the same results as Johnson et al. (2008): lies were accompanied by enhanced medial frontal negativities (MFN) and suppressed late positive components (LPCs) indicating that lying relied on stronger cognitive control processes and response conflicts than being honest. The amplitudes of pre-response positivities (PRP) were reduced for lies implying that lies about attitudes were accompanied by strategic monitoring. MFN amplitudes increased and LPC amplitudes decreased for lies about positively valued items revealing that lying about positively valued items is cognitively more challenging than lying about negatively valued items. As a new finding, MFN, LPC and PRP components were neither moderated by Machiavellianism nor by changes in the attitude ratings. The results indicate that LPC, MFN and PRP components are reliable indicators of the cognitive processes used during deception and that it is worthwhile to investigate them in further deception contexts.

Catecholaminergic Modulation of Semantic Processing in Sentence Comprehension.

Catecholamine (CA) function has been widely implicated in cognitive functions that are tied to the prefrontal cortex and striatal areas. The present study investigated the effects of methylphenidate, which is a CA agonist, on the electroencephalogram (EEG) response related to semantic processing using a double-blind, placebo-controlled, randomized, crossover, within-subject design. Forty-eight healthy participants read semantically congruent or incongruent sentences after receiving 20-mg methylphenidate or a placebo while their brain activity was monitored with EEG. To probe whether the catecholaminergic modulation is task-dependent, in one condition participants had to focus on comprehending the sentences, while in the other condition, they only had to attend to the font size of the sentence. The results demonstrate that methylphenidate has a task-dependent effect on semantic processing. Compared to placebo, when semantic processing was task-irrelevant, methylphenidate enhanced the detection of semantic incongruence as indexed by a larger N400 amplitude in the incongruent sentences; when semantic processing was task-relevant, methylphenidate induced a larger N400 amplitude in the semantically congruent condition, which was followed by a larger late positive complex effect. These results suggest that CA-related neurotransmitters influence language processing, possibly through the projections between the prefrontal cortex and the striatum, which contain many CA receptors.

Electrophysiological evidence that release from proactive inhibition reflects late semantic processing.

While proactive inhibition (PI) frequently occurs in response to novel stimuli due to interference from previously learned information, shifts in semantic category on a preceding trial lead to the attenuation of learning interference effects such as PI, resulting in significantly improved performance on short-term memory tasks. This study examined how the release from PI also leads to a reduction in semantic inhibition, as measured primarily through an event-related potential (ERP) electroencephalography (EEG) design. The study used Chinese characters denoting different categories (word nouns for categories such as plants, clothes, and flowers) to test short-term memory recall in a control group (same category/no PI release) and experimental group (different category/PI release). Both behavioral data (recall accuracy) and ERP responses for the N400 and Late Positive Component (LPC) at frontal, central, and parietal electrode sites were collected. Behaviorally, recall accuracy declined continuously on the initial three consecutive trials, regardless of group, while recall increased significantly on the last trial specifically for the experimental group, due to the shift in semantic category. We reported a significant interaction between group and electrode site for the LPC component, indicating that inhibition effects were still active for both groups at the initial memory encoding stage (corresponding to N400), with inhibition release in the experimental group occurring through later LPC processing. These results provide electrophysiological evidence that release from PI can be distinguished from semantic forms of processing through changes in amplitude over the course of learning.

Electrophysiological correlates of emotion word processing in Spanish–English bilinguals

AbstractWe examined how proficiency influences the processing of emotion words in Spanish–English bilinguals (22 balanced and 20 unbalanced). All unbalanced bilinguals were more proficient in English than Spanish. Participants rated the valence of negative, neutral, and positive words in both languages while EEG was being recorded. ERP latencies and amplitudes were analyzed for two components. The language effect was significant on the late positive component (LPC) amplitude, which was larger for emotion than for neutral words for both groups in English. The unbalanced group presented larger LPC amplitudes for positive than for neutral and for neutral than for negative words in Spanish, suggesting emotion processing differences in these participants’ less proficient language. Valence effects were consistent across languages for the balanced group, but not for the unbalanced group, perhaps reflecting differences in reactivity to emotion words in the less proficient language.

Electrophysiological correlates of the Categorization Working Memory Span task in older adults

Older adults typically show poor performance in tasks assessing working memory (WM), a crucial cognitive mechanism. The present study examined the electrophysiological correlates of a classic complex WM task often used in studies involving older adults, the Categorization Working Memory Span task (CWMS), by means of event-related potentials. Thirty-five healthy, right-handed older adults (64–75 years) were presented the CWMS task while a 38-channel EEG was measured, and the N1, P1, and word recognition potential (RP) were analyzed on four regions of interest (ROIs) of 5 electrodes each. Additionally, late positive components (P200 and P300) were analyzed in midline ROIs of 3 electrodes each. Participants also executed an n-back task (2-back condition) and an objective performance-based task (the Ability to solve Problems in Everyday life [APE]). At a behavioral level, significant correlations were found between the CWMS, the 2-back, and the APE tests. At a physiological level, N1 and word RP showed greater bilateral amplitude in posterior electrodes, but the better the CWMS and the 2-back performance, the greater the RP amplitude on posterior left sites. The CWMS task induced a clear P200 component, but its amplitude was not correlated with participants’ behavioral performance. Altogether, notwithstanding that the bilateral RP pattern elicited by the CWMS is a clear marker of WM processing in older adults, better elderly performers on this complex WM test showed greater left hemisphere dominance to the automatic word RP.

Stimulus complexity and chunk tightness interact to impede perceptual restructuring during problem solving

The mutual influence of stimulus complexity and chunk tightness on perceptual restructuring was examined using a chunk decomposition task (CDT). Participants attempted to remove components of Chinese characters in order to produce new, valid characters. Participants had their electroencephalogram recorded while completing a CDT in conditions of low or high stimulus complexity, crossed with two levels of chunk tightness. Tight chunks overlapped spatially whereas loose chunks did not. Both increasing chunk tightness and increasing stimulus complexity impaired performance (lower accuracy, longer reaction times), and these factors interacted such that highly complex, tight chunks produced the worst performance. These factors also had interacting effects on the late positive complex (LPC). The LPC amplitude was reduced by increasing chunk tightness, but this effect was attenuated for highly complex stimuli. These results suggest that though chunk tightness and stimulus complexity impair performance in the CDT, they have dissociable neural underpinnings.

Why do you attract me but not others? Retrieval of person knowledge and its generalization bring diverse judgments of facial attractiveness

ABSTRACT Judgments of facial attractiveness play an important role in social interactions. However, it still remains unclear why these judgments are malleable. The present study aimed to understand whether the retrieval of person knowledge leads to different judgments of attractiveness of the same face. Event-related potentials and learning-recognition tasks were used to investigate the effects of person knowledge on facial attractiveness. The results showed that compared with familiar faces that were matched with negative person knowledge, those matched with positive person knowledge were evaluated as more attractive and evoked a larger early posterior negativity (EPN) and late positive complex (LPC). Additionally, positive similar faces had the same behavioral results and evoked large LPC, while unfamiliar faces did not have any significant effects. These results indicate that the effect of person knowledge on facial attractiveness occurs from early to late stage of facial attractiveness processing, and this effect could be generalized based on the similarity of the face structure, which occurred at the late stage. This mechanism may explain why individuals form different judgments of facial attractiveness.

Probing the relationship between late endogenous ERP components with fluid intelligence in healthy older adults

The world population is rapidly aging, bringing together the necessity to better understand the advancing age. This characterization may be used to aid early diagnosis and to guide individually-tailored interventions. While some event-related potential (ERP) components, such as the P300 and late positive complex (LPC), have been associated with fluid intelligence (Gf) in young population; little is known whether these associations hold for older people. Therefore, the main goal of this study was to assess whether these ERP components are associated with Gf in the elderly. Fifty-seven older adults performed a continuous performance task (CPT) and a visual oddball paradigm while EEG was recorded. Participants were divided into two groups, according to their performance in the Raven’s Advanced Progressive Matrices test: high-performance (HP) and low-performance (LP). Results showed that the HP group, compared to the LP group, had higher LPC amplitudes in the CPT and shorter P300 latencies in the oddball task, highlighting the role of ERP components as a potential electrophysiological proxy of Gf abilities in the elderly.

Evaluating the Association of High Trait Anxiety With a Bias in Familiarity-Based Recognition of Emotional Stimuli

Abstract. In the past decades the role of cognitive biases as maintaining factors of anxiety has been widely researched. This theoretical framework assumes that vulnerability self-referential thoughts promote a hyper-vigilant mode of processing environmental stimuli. In this mode, threatening information increases attentional capture and therefore encoding and retrieval of such stimuli is enhanced. Although this attentional bias has been confirmed, the evidence concerning the memory bias is contradictory. Our hypothesis is that the bias in memory is expressed through the pattern of recognition. Particularly, the aim of this study was to evaluate the association of anxiety with familiarity, a deficient form of recognition which consists only in the identification of the item without retrieval of contextual information. Two groups of 17 participants with low and high anxiety levels performed an experimental task of visual recognition memory, using neutral, positive, and negative pictures. The experiment had two test phases, with a 24-hour interval, to evaluate possible effects of consolidation. The pattern of recognition was measured, behaviorally (through an independent Remember/Know paradigm) and through event-related potentials (ERP). Participants with higher levels of anxiety developed a bias in recognition of arousing stimuli (positive and negative) compared with the control group. This bias was observed behaviorally through an increase of familiarity-based recognition, and was associated with a positive modulation of a right parietal late positive component (LPC) at approximately 600 ms of latency. Participants with higher levels of anxiety are capable of recognizing arousing stimuli but lack efficiency in retrieving past contextual information compared to lower level anxiety participants. A recognition bias can be the first step in cognitive distortions that generate anxiety. This is, to our knowledge, the first study to explore the association of anxiety with familiarity-based recognition, using an independent Remember/Know paradigm combined with electrophysiological data. Further studies with bigger samples and more recording channels are needed to confirm the electrophysiological findings.

Processing Code-Switches in the Presence of Others: An ERP Study.

Code-switching is highly socially constrained. For instance, code-switching is only felicitous when those present are fluent in both languages. This means that bilinguals need to dynamically adjust their language control and expectation of code-switching to the current social situation or context. The aim of the present EEG study was to investigate how and when language control in the comprehension of code-switches is affected by the assumed language knowledge of others in the context. Spanish-English bilinguals read sentences with and without code-switches together with another Spanish-English bilingual or with an English monolingual. Switches elicited an early fronto-central positivity. This effect was smaller overall when a bilingual was present at the start of the study. In addition, the late positive complex found for switches was smaller when a bilingual was present rather than a monolingual, but only for those participants who were sensitive to the other’s language knowledge in their off-line judgments. These findings suggest that the bilinguals in our study expected and activated both languages when initially paired with a bilingual and that they more easily accommodated code-switches, in the presence of a bilingual than in the presence of a monolingual. Our findings support the view that language control can be modulated by the perceived language knowledge of others present, and are compatible with a dynamic control model of bilingual language comprehension.

Tension Experience Induced By Nested Structures In Music.

Tension experience is the basis for music emotion. In music, discrete elements are always organized into complex nested structures to convey emotion. However, the processing of music tension in the nested structure remains unknown. The present study investigated the tension experience induced by the nested structure and the underlying neural mechanisms, using a continuous tension rating task and electroencephalography (EEG) at the same time. Thirty musicians listened to music chorale sequences with non-nested, singly nested and doubly nested structures and were required to rate their real-time tension experience. Behavioral data indicated that the tension experience induced by the nested structure had more fluctuations than the non-nested structure, and the difference was mainly exhibited in the process of tension induction rather than tension resolution. However, the EEG data showed that larger late positive components (LPCs) were elicited by the ending chords in the nested structure compared with the non-nested structure, reflecting the difference in cognitive integration for long-distance structural dependence. The discrepancy between resolution experience and neural responses revealed the non-parallel relations between emotion and cognition. Furthermore, the LPC elicited by the doubly nested structure showed a smaller scalp distribution than the singly nested structure, indicating the more difficult processing of the doubly nested structure. These findings revealed the dynamic tension experience induced by the nested structure and the influence of nested type, shedding new light on the relationship between structure and tension in music.

Code-Switching Does Not Equal Code-Switching. An Event-Related Potentials Study on Switching From L2 German to L1 Russian at Prepositions and Nouns

Studies on event-related potentials (ERP) in code-switching (CS) have concentrated on single-word insertions, usually nouns. However, CS ranges from inserting single words into the main language of discourse to alternating languages for larger segments of a discourse, and can occur at various syntactic positions and with various word classes. This ERP study examined native speakers of Russian who had learned German as a second language; they were asked to listen to sentences with CS from their second language, German, to their first language, Russian. CS included either a whole prepositional phrase or only the lexical head noun of a prepositional phrase. CS at nouns resulted in a late positive complex (LPC), whereas CS at prepositions resulted in a broad early negativity, which was followed by an anterior negativity with a posterior positivity. Only in the last time window (800–1000 ms) did CS at prepositions result in a broad positivity similar to CS at nouns. The differences between both types of CS indicate that they relate to different psycholinguistic processes.