Late Positive Component Research Articles

Modulatory Effects of Prediction Accuracy on Electroencephalographic Brain Activity During Prediction.

Prediction is essential for the efficiency of many cognitive processes; however, this process is not always perfect. Predictive coding theory suggests that the brain generates and updates a prediction to respond to an upcoming event. Although an electrophysiological index of prediction, the stimulus preceding negativity (SPN), has been reported, it remains unknown whether the SPN reflects the prediction accuracy, or whether it is associated with the prediction error, which corresponds to a mismatch between a prediction and an actual input. Thus, the present study aimed to investigate this question using electroencephalography (EEG). Participants were asked to predict the original pictures from pictures that had undergone different levels of pixelation. The SPN amplitude was affected by the level of pixelation and correlated with the subjective evaluation of the prediction accuracy. Furthermore, late positive components (LPC) were negatively correlated with SPN. These results suggest that the amplitude of SPN reflects the prediction accuracy; more accurate prediction increases the SPN and reduces the prediction error, resulting in reduced LPC amplitudes.

ERP evidence of age-related differences in emotional processing.

The present study used event-related potentials (ERPs) to examine differences in the temporal dynamics of emotion processing in young and older adults, with a specific focus on the positivity effect, that is, the preferential processing of positive over negative information. To this aim, we used a language paradigm that allowed us to investigate early ERP components as well as later components, namely the N400 and the late positive complex (LPC). Young and older adults were presented with neutral sentence stems with positive, negative or neutral/semantically-incongruent critical word endings while their electrical brain activity was recorded. There were no effects of emotional valence on early ERP components. Instead, a positivity effect was evident in young adults indexed by reduced N400s for positive sentence endings. Perhaps due to reduced semantic processing abilities, older adults did not show any N400 effect. ERP effects in this group were evident at a later processing stage and took the form of larger LPCs for neutral/incongruent information. Overall, there was no effect of emotional valence on either the N400 or the LPC in older adults. Our data suggest that with age, more effortful semantic processing may deplete resources for emotional processing.

Novel Adjective Processing in Preschool Children: Evidence From Event-Related Brain Potentials.

Purpose Recent findings in preschool children indicated novel adjective recall was enhanced when learned using repeated retrieval with contextual reinstatement (RRCR) compared to repeated study (RS). Recall was similar for learned pictures used during training and new (generalized) pictures with the same adjective features. The current study compared the effects of learning method and learned/generalized pictures on the neural processes mediating the recognition of novel adjectives. Method Twenty typically developing children aged 4;6-5;11 (years;months) learned four novel adjectives, two using RRCR and two using RS. Five-minute and 1-week tests assessed adjective recall using learned and generalized pictures. Also, at the 1-week visit, event-related potentials (ERPs) were recorded to assess children's processing of learned/generalized pictures, followed by naturally spoken novel adjectives in a match-mismatch paradigm. Results Naming recall and match-mismatch judgment accuracy were similar for the RS and RRCR conditions and across learned/generalized pictures. However, ERPs revealed more reliable condition effects in the phonological mapping negativity, indexing phonological expectations, and the late positive component, indexing semantic reanalysis, for the adjectives learned in the RRCR relative to the RS condition. Unfamiliar pictures (generalized) elicited larger amplitude N300 and N400 components relative to learned pictures. Conclusions Although behavioral accuracy measures suggest similar effects of the RS and RRCR learning conditions, subtle differences in the ERPs underlying novel adjective processing indicate advantages of RRCR for phonological processing and semantic reanalysis. While children readily generalized the novel adjectives, ERPs revealed greater cognitive resources for processing unfamiliar compared to learned pictures of the novel adjective characteristics. Supplemental Material https://doi.org/10.23641/asha.13683214.

Left-hemispheric predominance on appropriateness evaluation of restructuring during chunk decomposition problem solving.

Restructuring refers to achieving satisfactory solutions by breaking obstacles or forming novel associations in problem-solving. One critical question arises regarding how an appropriate solution is processed in our brain during the restructuring of problem representations. This study aims to explore the electrophysiological correlates of appropriateness evaluation of restructuring by employing a chunk decomposition task. During loose or tight chunk decomposition, participants needed to assess whether they could get a valid solution after probe removal from a source character chunk. As reflected by the late positive complex, the processing of appropriateness exhibited the greatest effect (appropriate vs. inappropriate) in left parietal regions for tight chunk decomposition, but exhibited insignificant differences across most brain regions for loose chunk decomposition. This study provides the first primary electrophysiological evidence that both hemispheres contribute to and the left hemisphere plays a predominant role in evaluating the appropriateness of restructuring in problem solving.

Brain responses of dysphoric and control participants during a self-esteem implicit association test.

Previous studies have reported lowered implicit self-esteem at the behavioral level among depressed individuals. However, brain responses related to the lowered implicit self-esteem have not been investigated in people with depression. Here, event-related potentials were measured in 28 dysphoric participants (individuals with elevated amounts of depressive symptoms) and 30 control participants during performance of an implicit association task (IAT) suggested to reflect implicit self-esteem. Despite equivalent behavioral performance, differences in brain responses were observed between the dysphoric and the control groups in late positive component (LPC) within 400-1,000ms poststimulus latency. For the dysphoric group, self-negativity mapping stimuli (me with negative word pairing and not-me with positive word pairing) induced significantly larger LPC amplitude as compared to self-positivity mapping stimuli (me with positive pairing and not-me with negative pairing), whereas the control group showed the opposite pattern. These results suggest a more efficient categorization toward implicit self-is-negative association, possibly reflecting lower implicit self-esteem among the dysphoric participants, in comparison to the controls. These results demonstrate the need for further investigation into the functional significance of LPC modulation during IAT and determination of whether LPC can be used as a neural marker of depressive-related implicit self-esteem.

Context-based interpersonal relationship modulates social comparison between outcomes: an event-related potential study

Social comparison is a common behavior that largely determines people’s experience of decision outcome. Previous research has showed that interpersonal relationship plays a pivotal role in social comparison. In the current study, we investigated whether the manipulation of context-based relationship would affect participants’ comparison of self-outcome and other-outcome. Participants first finished a trust game with likeable (dislikeable) partner and then they were involved in a gambling task and observed the outcomes for themselves and for partners. According to self-reports, participants were more satisfied with likeable partner’s gains than losses only when they received gains, but they were always more satisfied with dislikeable player’s losses compared to gains. Event-related potentials including the feedback-related negativity (FRN), P3 and late positive component (LPC) were sensitive to context-based relationship. Specifically, the prediction error signal (indexed by the FRN) was largest when participants received losses but dislikeable player received gains. Meanwhile, the P3 indicates that participants had stronger motivation to outperform dislikeable player. Finally, the LPC was larger when participants received the same outcomes with dislikeable players. In general, our results support the key point of the self-evaluation maintenance model that personal closeness modulates subjective sensitivity when drawing a comparison of one’s outcomes with other’s outcomes.

The fate of the unexpected: Consequences of misprediction assessed using ERP repetition effects

Amid increasing interest in the role of prediction in language comprehension, there remains a gap in our understanding of what happens when predictions are disconfirmed. Are unexpected words harder to process and encode because of interference from the original prediction? Or, because of their relevance for learning, do expectation violations strengthen the representations of unexpected words? In two experiments, we used event-related potentials to probe the downstream consequences of prediction violations. Critical words were unexpected but plausible completions of either strongly constraining sentences, wherein they constituted a prediction violation, or weakly constraining sentences that did not afford a clear prediction. Three sentences later the critical word was repeated at the end of a different, weakly constraining sentence. In Experiment 1, repeated words elicited a reduced N400 and an enhanced late positive complex (LPC) compared to words seen for the first time. Critically, there was no effect of initial sentence constraint on the size of the repetition effect in either time window. Thus, prediction violations did not accrue either costs or benefits for later processing. Experiment 2 used the same critical items and added strongly constraining filler sentences with expected endings to further promote prediction. Again, there was no effect of initial sentence constraint on either the N400 or the LPC to repeated critical words. When taken with prior findings, the results suggest that prediction is both powerful and flexible: It can facilitate processing of predictable information by reducing encoding effort without causing processing difficulties for unexpected inputs.

Eye region as a predictor of holistic facial aesthetic judgment: An eventrelated potential study

Event-related potentials (ERP) play an important role in the early detection of emotional arousal. Previous studies of aesthetics have shown that the positive component appearing around 200 ms after stimulus (P2) and the larger late positive component (LPC) are closely related to the early stage of aesthetic judgment. We investigated the temporal features of facial aesthetic judgment on the basis of facial features by using the ERP technique. Participants were instructed to predict holistic face aesthetic level based on the regions of eyes, mouth, or nose. Behavioral results show that holistic score predictions based on the eye region were no different to holistic aesthetic ratings. The ERP analysis results show that beautiful eyes and faces elicited a smaller P2 amplitude and LPC amplitude when judging the holistic aesthetic. The P2 effect of facial aesthetics may reflect automatic processing of facial aesthetics and the difference in LPC may be related to motivational attention to facial aesthetics. Because of the similar ERP effect between the holistic facial aesthetic judgment and the aesthetic judgment of eye region, this region may play a significant role in predicting holistic facial aesthetics. The implication is that the eyes are not only a window to the soul, but also a benchmark of beauty.

Imagery processing in action memory–mental imagery is necessary to the subject-performed task effect

ABSTRACT The generation of the subject-performed task (SPT) effect in action memory involves multiple factors, including imagery processing, but its role is unclear. This study uses event-related potential (ERP) technology to explore it in the SPT effect by controlling different encoding types (performance encoding with open eyes or closed eyes, imagery encoding, verbal encoding). Behavioural results showed that the correct rate of recognition under the first three conditions was significantly larger than it for verbal encoding, and there was an SPT effect. The ERP and behavioural results were consistent, and the SPT effect was also found, indicating that the effect could be caused by both performance and imagery encoding. At the Cz electrode site, performance and imagery encoding both induced larger late positive components than verbal encoding. This late positive component could indicate that imagery processing improves memory performance. This study showed that the imagery processing is necessary to the SPT effect.

Differences in Explicit Stereotype Activation among Social Groups Based on the Stereotype Content Model: Behavioral and Electrophysiological Evidence in Chinese Sample.

The stereotype content model (SCM; Fiske, Cuddy, Glick and Xu, 2002) identifies four basic categories of stereotyped social groups: high warmth-high competence (HW-HC), high warmth-low competence (HW-LC), low warmth-high competence (LW-HC), and low warmth-low competence (LW-LC). However, many of these groups have not been directly examined in stereotype activation research. The purpose of the present research was to extend stereotype activation research to groups that more fully represent those identified under the SCM. Employing explicit sequential priming task, participants responded to prime-target stimulus pairs that were either congruent or incongruent with stereotypes of social groups from all four SCM quadrants in two studies in the current investigation. Study 1 was to determine the behavioral pattern of explicit stereotype activation among four quadrants (the sample included 60 Chinese undergraduate students, 51%—female). Study 2 further employed event-related brain potentials (ERPs) technique to track the time course and electrophysiological underpinnings of explicit stereotype activation (the sample included 22 right-handed Chinese undergraduate students, 76%—female). In Study 1, participants responded more quickly and accurately on stereotype congruent trials than incongruent trials for all social groups except LW-LC groups. This reverse priming effect on LW-LC social groups in RTs was also replicated in Study 2. ERPs findings further showed that incongruent targets elicited larger N400 amplitudes than congruent targets for all four SCM quadrants. Moreover, congruent targets elicited larger P2 than incongruent targets, but only found for the LW-LC social groups. In addition, congruent targets elicited larger amplitudes of late positive component than incongruent targets for the low warmth (LW-LC and LW-HC) groups. Together, these results highlight the unique processing that LW-LC groups receive throughout the cognitive stream, ultimately manifesting in distinctive behavioral responses. Unconscious activation of egalitarian goals, disgust, and distrust accounts are discussed.

Which digit is larger? Brain responses to number and size interactions in a numerical Stroop task.

When comparing the digits of different physical sizes, the processing of numerical value interacts with the processing of physical size. Given the universal use of Arabic numbers in mathematics and daily life, this study aims to elucidate the cognitive processes involved in the interactions of task-relevant and task-irrelevant features during information processing. We investigated this question by examining event-related potential (ERP) using a modified version of the size congruity comparison, which is a Stroop-like task. Numerical value and physical size were varied independently under task-relevant and task-irrelevant conditions. To better examine how the task-irrelevant features modulated the processing of the task-relevant attributes, a neutral condition was included in both tasks. For the physical task, congruent trials showed a less negative N200 response than neutral trials (indicating a facilitation effect), and incongruent trials elicited a larger N450 and smaller late positive complex (LPC) response than neutral trials (indicating an interference effect). For the numerical task, congruent trials showed a larger LPC response than neutral trials (indicating a facilitation effect). These ERP findings indicate that the sources of the facilitation and interference effects appear in different cognitive processes for each task. We further suggest that language characteristics may be a factor in the superior numerical processing exhibited in this study.

The neural and cognitive time course of intention reasoning: Electrophysiological evidence from ERPs.

Intention is a typical mental state in the theory of mind. However, to date, there have been theoretical debates on the conceptual structure of intention. The neural and cognitive time course of intention reasoning remains unclear. The present event-related potential (ERP) study had two purposes: first, to investigate the neural correlates of intention reasoning based on a differentiated conceptual structure distinguishing desire and intention; second, to investigate the neural basis of intention reasoning for different agents. Thus, we compared the neural activity elicited by intention reasoning for self and for others when the intention matched or mismatched the desire of the agent. The results revealed that three ERP components distinguished among different types of intention reasoning. A negative-going ERP deflection with right frontal distribution between 400 and 500 ms might reflect the cognitive conflict involved in intention reasoning, a right frontal late positive component might be associated with the categorisation of agents, and a centro-parietal late slow wave might indicate the conceptual mental operations associated with decoupling mechanisms in intention processing. These findings implied the neural and cognitive time course of intention reasoning and provided neural evidence for the differentiated conception of intention.

A MEG Study of Visual Repetition Priming in Schizophrenia: Evidence for Impaired High-Frequency Oscillations and Event-Related Fields in Thalamo-Occipital Cortices.

Background: Cognitive dysfunctions represent a core feature of schizophrenia and a predictor for clinical outcomes. One possible mechanism for cognitive impairments could involve an impairment in the experience-dependent modifications of cortical networks.Methods: To address this issue, we employed magnetoencephalography (MEG) during a visual priming paradigm in a sample of chronic patients with schizophrenia (n = 14), and in a group of healthy controls (n = 14). We obtained MEG-recordings during the presentation of visual stimuli that were presented three times either consecutively or with intervening stimuli. MEG-data were analyzed for event-related fields as well as spectral power in the 1–200 Hz range to examine repetition suppression and repetition enhancement. We defined regions of interest in occipital and thalamic regions and obtained virtual-channel data.Results: Behavioral priming did not differ between groups. However, patients with schizophrenia showed prominently reduced oscillatory response to novel stimuli in the gamma-frequency band as well as significantly reduced repetition suppression of gamma-band activity and reduced repetition enhancement of beta-band power in occipital cortex to both consecutive repetitions as well as repetitions with intervening stimuli. Moreover, schizophrenia patients were characterized by a significant deficit in suppression of the C1m component in occipital cortex and thalamus as well as of the late positive component (LPC) in occipital cortex.Conclusions: These data provide novel evidence for impaired repetition suppression in cortical and subcortical circuits in schizophrenia. Although behavioral priming was preserved, patients with schizophrenia showed deficits in repetition suppression as well as repetition enhancement in thalamic and occipital regions, suggesting that experience-dependent modification of neural circuits is impaired in the disorder.

Prisoners of Addictive Cues: Biobehavioral Markers of Overweight and Obese Adults with Food Addiction.

Obesity is associated with food and eating addiction (FA), but the biobehavioral markers of this condition are poorly understood. To characterize FA, we recruited 18 healthy controls and overweight/obese adults with (n = 31) and without (n = 17) FA (H-C, FAOB, NFAOB, respectively) to assess alpha brain asymmetry at rest using electroencephalogram; event-related potentials following exposure to high-calorie food (HCF), low-calorie food (LCF), and nonfood (NF) images in a Stroop paradigm; reaction time reflective of the Stroop bias; and symptoms of depression and disordered eating behavior. The FAOB group had the greatest emotional and uncontrollable eating, depressive, and binge-eating symptoms. The FAOB group displayed lower resting left alpha brain asymmetry than that of the NFAOB group. Differently from the other groups, the FAOB group presented attenuated Stroop bias following exposure to HCF relative to NF images, as well as a lower late positive potential component (LPPb; 450–495 ms) in both frontal and occipital regions. In the total cohort, a correlation was found between the Stroop bias and the LPPb amplitude. These results point to biobehavioral hypervigilance in response to addictive food triggers in overweight/obese adults with FA. This resembles other addictive disorders but is absent in overweight/obesity without FA.

The enhancement of appetite through the use of colored light in case of a cake: Preliminary evidence from event‐related potentials

AbstractAppetites are strongly affected by the color of the food and it has been found that different colors can affect the brain reflexes that impact the appetite. In this study, event‐related potential was used as a measurement tool to detect brain wave responses to assess foods under different colors of light, and to compare the appetite performance of participants. The food samples were captured under incandescent lights and colored lights (red and green lights under 5200 K). The incandescent lights were divided into the differential color temperature (2700, 4000, 6500 and 7500 K). Seventeen participants were invited to the experiment. The event‐related potential results showed that the warm incandescent light (4000 K) significantly increased appetite. Moreover, the red light enhances the late positive component amplitude and enhances the consumer's visual attraction and impression. The conclusions showed that the color of lighting can affect consumers' emotions, behaviors, psychology, and even appetite, and preliminary scientific evidence has been obtained from event‐related potential.

Brain indices associated with semantic cues prior to and after a word in noise

It is well established that identification of words in noise improves when it is preceded by a semantically related word, but comparatively little is known about the effect of subsequent context in guiding word in noise identification. We build on the findings of a previous behavioural study (Chan & Alain, 2019) by measuring neuro-electric brain activity while manipulating the semantic content of a cue that either preceded or followed a word in noise. Participants were more accurate in identifying the word in noise when it was preceded or followed by a cue that was semantically related. This gain in accuracy coincided with a late positive component, which was time-locked to the word in noise when preceded by a cue and time-locked to the cue when it followed the word in noise. Distributed source analyses of this positive component revealed different patterns in source activity between the two temporal conditions. The effects of relatedness also generated an event-related potential modulation around 400 ms (N400) that was present at cue presentation when it followed the word in noise, but not for the word in noise when preceded by the cue, consistent with findings regarding its sensitivity to signal degradation. Exploratory analyses examined a subset of data based on participants’ subjective perceived clarity, which revealed a posterior deflection over the left hemisphere that showed a relatedness effect. We discuss these findings in light of research on prediction as well as a reflective attention framework.

Outcome Evaluation Affects Facial Trustworthiness: An Event-Related Potential Study.

Facial trustworthiness and feedback information of trustees can influence trustors’ investment behavior in trust games. This study investigated the temporal features of outcome evaluation (evaluation of feedback) and how they influence the processing of facial trustworthiness. A total of 25 college students participated in a decision-making task in which feedback was presented prior to a face stimulus. The decision of participants to continue investing was evaluated. We observed that trustors were more inclined to keep investing in trustworthy trustees or those appearing after positive feedback (gains). Event-related potential (ERP) results revealed that in the face presentation stage, trustworthy faces with losses induced more negative feedback-related negativity (FRN) than did trustworthy faces with gains and untrustworthy faces with losses. Further, faces that did not meet expectations induced more negative FRN. Trustworthy faces with gains induced more positive late positive component (LPC) than did trustworthy faces with losses and generated more motivated attention. Bottom–up and top–down processes were integrated for facial trustworthiness perception at different stages. In sum, top–down processing exerted a greater impact during the early stage of facial trustworthiness perception, both top–down and bottom–up processing were involved in the medium term, and bottom–up processing exerted a greater impact in the later stage.

Word stress processing integrates phonological abstraction with lexical access – An ERP study

It is unclear whether word stress in a language is stored as part of the word or whether it is generated by a rule. We test the generativist hypothesis of lexical storage stating that only unpredictable stress is stored in long-term memory against the contrasting usage-based approach assuming that all phonetic information regardless of its (un)predictability is stored in the mental lexicon together with the word. In a correctness judgment task involving correctly and incorrectly stressed penults and antepenults, we found that incorrectly stressed penults do not evoke an N400 effect, whereas incorrectly stressed antepenults do: there is increased negativity with a peak latency around 350–600 ms from word onset. Only changes to words with exceptional stress cause lexical inhibition, hence exceptional but not default stress markers are stored in the lexicon. Additionally, differences in processing patterns between the N400 and the late positivity component window point to an integration of two stages of word processing: pre-lexical stress recognition and stress-to-meaning matching. The results of the study support the view that stress should be understood as abstract phonological information. • Changes to the original stress in exceptions, but not words with default stress cause lexical inhibition in Spanish. • Following the generative phonology framework, predictable stress information is not stored in the lexicon. • Combined N400 and positivity effects show integration of pre-lexical stress recognition and stress-to-meaning matching. • Electrophysiological data confirm that stress is an abstract phonological category.

The influence of the cross-modal emotional pre-preparation effect on audiovisual integration.

Previous studies have shown that the cross-modal pre-preparation effect is an important factor for audiovisual integration. However, the facilitating influence of the pre-preparation effect on the integration of emotional cues remains unclear. Therefore, this study examined the emotional pre-preparation effect during the multistage process of audiovisual integration. Event-related potentials (ERPs) were recorded while participants performed a synchronous or asynchronous integration task with fearful or neutral stimuli. The results indicated that, compared with the sum of the unisensory presentation of visual (V) and auditory (A) stimuli (A+V), only fearful audiovisual stimuli induced a decreased N1 and an enhanced P2; this was not found for the neutral stimuli. Moreover, the fearful stimuli triggered a larger P2 than the neutral stimuli in the audiovisual condition, but not in the sum of the combined (A+V) waveforms. Our findings imply that, in the early perceptual processing stage and perceptual fine processing stage, fear improves the processing efficiency of the emotional audiovisual integration. In the last cognitively assessing stage, the fearful audiovisual induced a larger late positive component (LPC) than the neutral audiovisual. Moreover, the asynchronous-audiovisual induced a greater LPC than the synchronous-audiovisual during the 400-550 ms period. The different integration effects between the fearful and neutral stimuli may reflect the existence of distinct mechanisms of the pre-preparation in terms of the emotional dimension. In light of these results, we present a cross-modal emotional pre-preparation effect involving a three-phase emotional audiovisual integration.

Older Adults Encode Task-Irrelevant Stimuli, but Can This Side-Effect be Useful to Them?

We studied whether, due to deteriorating inhibitory functions, older people are more likely to process irrelevant stimuli; and if so, could they later use this information better than young adults. In the study phase of our experiment, a Posner-type gaze-cued version of a Simon task was performed in which we presented task-irrelevant cues, where faces or patches with either left- or right-looking dots for the pupil of the eye preceded the task to press a button congruent or incongruent with the presentation side of the target stimulus. In the follow-up test phase, participants completed an unexpected facial recognition test. In the study phase not only a decreased P1, but also an increased N170 amplitude of the event-related potentials (ERPs) were found in older, compared to younger adults, and also for faces compared to patches. Even though in the test phase both age-groups could recognize the faces better than statistically by chance, neither the older nor the younger participants could discriminate them effectively. The late positive component (LPC)—the ERP correlates of the old/new effect, being the higher amplitude for the earlier presented stimuli when compared with the unseen stimuli during the recognition test—was not evolved in the older group, while a reversed old/new effect was seen in younger participants: higher amplitude was found in New-Right and Old-Wrong conditions (for faces they did not recognize independent of seeing them before) compared to Old-Right and New-Wrong conditions (for faces they thought they recognized from the study phase). In conclusion, although older adults showed enhanced processing of task-irrelevant stimuli compared to younger adults, as indicated by the N170 amplitude, however, they were not able to utilize this information in a later task, as was suggested by the recognition rate and LPC amplitude results.