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Self-knowledge is a type of personal semantic knowledge that concerns one’s self-image and personal identity. It has most often been operationalized as the summary of one’s personality traits (“I am a stubborn person”). Interestingly, recent studies have revealed that the neural correlates of self-knowledge can be dissociated from those of general semantic and episodic memory in young adults. However, studies of “dedifferentiation” or loss of distinctiveness of neural representations in ageing suggest that the neural correlates of self-knowledge might be less distinct from those of semantic and episodic memory in older adults. We investigated this question in an event-related potential (ERP) study with 28 young and 26 older adults while they categorised personality traits for their self-relevance (self-knowledge conditions), and their relevance to certain groups of people (general semantic condition). Participants then performed a recognition test for previously seen traits (episodic condition). The amplitude of the late positive component (LPC), associated with episodic recollection processes, differentiated the self-knowledge, general semantic, and episodic conditions in young adults, but not in older adults. However, in older adults, participants with higher composite episodic memory scores had more differentiated LPC amplitudes across experimental conditions. Moreover, consistent with the fact that age-related neural dedifferentiation may be material and region specific, in both age groups some differences between memory types were observed for the N400 component, associated with semantic processing. Taken together, these findings suggest that declarative memory subtypes are less distinct in ageing, but that the amount of differentiation varies with episodic memory function.

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 current study aims to investigate how Field independent (FI) and Field-dependent (FD) cognitive styles modulate bilingual language control during a joint language switching task. The cognitive styles were measured by the Group Embedded Figures Test (GEFT). The FI group with a preference for autonomous information processing was sensitive to role switching earlier at the cue stage, eliciting a more negative-going N2 in the cross-person condition than in the within-person condition. While the FD group, with a holistic processing style, discerned such role switching later, inducing a more positive-going late positive component (LPC) in the cross-person condition. In addition, the FD group exercised more cognitive control to suppress the interference from the L1 lemma, indexed by larger LPC amplitudes for L2 switch trials than L1 switch trials in the within-person condition. These findings suggest that FDI cognitive styles modulate bilingual language control mechanism through different manners of information processing.

BACKGROUND Item memory and source memory are differently processed with both behavioral and event-related potential (ERP) evidence. Reality monitoring, a specific type of source memory, which refers to the ability to differentiate external sources from internal sources, has been drawing much attention. Among factors that have an impact on reality monitoring, fluency has not been well-studied. Therefore, the current study aimed to investigate whether fluency could affect reality monitoring, through observations on both behavioral performance and electrophysiological patterns. MATERIAL AND METHODS Adopting ERP techniques, participants were required either to watch the presentation of a name/picture pair, or to imagine a picture for each displayed name, once (low fluency) or twice (high fluency). Later they completed a reality monitoring task of identifying names as perceived, imagined, or novel items. Behavioral performance was measured, and ERP waveforms were recorded. RESULTS Behaviorally, high fluency items were faster and more accurately attributed to the sources than low fluency items. ERP waveforms revealed that late positive component (LPC) occurred for all 4 types of items, while imagined items of low fluency did not record a robust FN400 or late frontal old/new effect. CONCLUSIONS As results revealed, the factor of fluency does influence reality monitoring in terms of accuracy and responding speed. Meanwhile, for imagined items of low fluency, the absence of FN400 and frontal old/new effect also suggests the sensitivity of reality monitoring to fluency, because these representatives of familiarity-based processing and post-retrieval monitoring are inevitably involved in the process of differentiating internal source from external source.

Successful episodic memory requires binding of event details across spatial and temporal gaps. The neural processes underlying mnemonic binding, however, are not fully understood. Moreover, although acute stress is known to modulate memory, if and how stress changes mnemonic integration across time and space is unknown. To elucidate these issues, we exposed participants to a stressor or a control manipulation shortly before they completed, while electroencephalography was recorded, an encoding task that systematically varied the demands for spatial and temporal integration. Associative memory was tested 24 h later. While early event-related potentials, including the P300 and Late Positive Component, distinguished different levels of spatiotemporal discontinuity, only later Slow Waves were linked to subsequent remembering. Furthermore, theta oscillations were specifically associated with successful mnemonic binding. Although acute stress per se left mnemonic integration largely unaffected, autonomic activity facilitated object memory and glucocorticoids enhanced detail memory, indicative for mnemonic integration. At the neural level, stress amplified the effects of spatiotemporal discontinuity on early information processing. Together, our results indicate that temporal and spatial gaps recruit early neural processes, providing attentional resources. The actual binding success, however, appears to depend on later processes as well as theta power and may be shaped by major stress response systems.

Emotional valence is known to influence word processing dependent upon concreteness. Whereas some studies point towards stronger effects of emotion on concrete words, others claim amplified emotion effects for abstract words. We investigated the interaction of emotion and concreteness by means of fMRI and EEG in a delayed lexical decision task. Behavioral data revealed a facilitating effect of high positive and negative valence on the correct processing of abstract, but not concrete words. EEG data yielded a particularly low amplitude response of the late positive component (LPC) following concrete neutral words. This presumably indicates enhanced allocation of processing resources to abstract and emotional words at late stages of word comprehension. In fMRI, interactions between concreteness and emotion were observed within the semantic processing network: the left inferior frontal gyrus (IFG) and the left middle temporal gyrus (MTG). Higher positive or negative valence appears to facilitate semantic retrieval and selection of abstract words. Surprisingly, a reversal of this effect occurred for concrete words. This points towards enhanced semantic control for emotional concrete words compared to neutral concrete words. Our findings suggest fine-tuned integration of emotional valence and concreteness. Specifically, at late processing stages, semantic control mechanisms seem to integrate emotional cues depending on the previous progress of semantic retrieval.

Previous studies on task or rule shifting have shown that the switch cost is affected by the hierarchical level of abstraction. The present study aimed to explore the neural correlates of hierarchical modulation in rule shifting. Participants were required to respond to number stimuli (1–9, excluding 5) while adhering to alternative rules cued by different perceptual features of the stimuli. Across trials, the rules might repeat or shift at either high or low hierarchical levels. Behavioral results indicated that the reaction times were significantly slower in the high-shift than in the low-shift condition. The electrophysiological results revealed (1) significant difference in P300 between high- and low-shift conditions, with larger P300 in the high-shift condition; and (2) increased amplitude of the late positive component (LPC) elicited by the high-shift condition as compared to that by the low-shift condition. These findings demonstrate that the task-set reconfiguration and rule selection is more difficult for higher hierarchical level of rule shifting as compared with lower level.

The first theoretical model on the neurophysiological basis of the N400: the deflection reflects layer I dendritic plateaus on a preparatory state of synaptic integration that precedes layer V somatic burst firing for conscious identification of the higher-order features of the stimulus (a late positive shift). Plateaus ensue from apical disinhibition by vasoactive intestinal polypeptide-positive interneurons (VIPs) through suppression of Martinotti cells, opening the gates for glutamatergic feedback to trigger dendritic regenerative potentials. Cholinergic transients contribute to these dynamics directly, holding a central role in the N400 deflection. The stereotypical timing of the (frontal) glutamatergic feedback and the accompanying cholinergic transients account for the enigmatic "invariability" of the peak latency in the face of a gamut of different stimuli and paradigms. The theoretical postulations presented here may bring about unprecedented level of detail for the N400 deflection to be used in the study of schizophrenia, Alzheimer's disease and other higher-order pathologies. The substrates of a late positive component, the Mismatch Negativity and the Semantic Prediction Potentials are also surveyed.

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.

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 400-1,000 ms 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.

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.

Adaptation to sensory events of long or short duration leads to a negative aftereffect, in which a new target event (of median duration) following the adaptation will be perceived to be shorter or longer than is actually the case. This illusion has been observed in visual, auditory, and tactile modalities. This study used event-related potentials (ERPs) to examine the tactile duration aftereffect, using the contingent negative variation (CNV) and the late positive component (LPC) as a way to characterize the temporal processes. The tactile duration adaptation was found to induce a significant aftereffect within a somatotopic framework. Moreover, the CNV in the contralateral scalp and the LPC in the fronto-central scalp were both modulated by the tactile duration adaptation. Specifically, adaptation to a short tactile duration increased the CNV and LPC amplitudes, whereas adaptation to a long tactile duration decreased them. This modulation was contingent on the topographic distance between fingers, which was only observed when the adapting and test fingers were consistent or adjacent, but not homologous. In sum, these results reveal a coherent behavioral-electrophysiological link in the somatotopically organized tactile duration aftereffect.

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.

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.

Contains fulltext : 216594.pdf (Publisher’s version ) (Open Access) Electrophysiological studies on recognition memory have identified several brain signals that are associated with subjective perceived confidence. However, the extent these brain signals reflect a generic process and are independent of the type of information recognized remains an open question. To address this issue, twenty-seven healthy volunteers performed an episodic memory task while their electro-encephalogram (EEG) was recorded. Participants encoded a set of abstract pictures, and subsequently rated their confidence on recognition decisions. Similar to results reported in previous studies using concrete words, we found retrieval-related theta power, FN400 and late positive component (LPC) effects. In contrast to previous studies using verbal material, a subsequent memory effect for encoding-related parietal evoked theta power, sensitive to subjectively perceived memory confidence, was observed. Our findings suggest that memorizing abstract pictures instead of concrete verbal material influences subsequent memory effects, yet does not affect the FN400, LPC and theta power during retrieval. 7 p.

Emotion exerts varied influences on memory. While task-relevant item memory is often enhanced by emotion, associative memory is generally impaired. Unitization is known to improve associative memory, but its effects and mechanisms in protecting associative memory from emotional interference are rather obscure. The current study investigated associative memory by employing experimental manipulation of unitization (vs. nonunitization) encoding strategy and stimulus emotion (neutral, intrinsic negative, and extrinsic negative), combined with event-related potential (ERP) signatures of familiarity (FN400 old/new effects) and recollection (parietal late positive component/LPC old/new effects) in memory recognition. Both behavioral and ERP indices of associative recognition from the nonunitization group confirmed emotional interference in associative memory. Importantly, it was primarily intrinsic (vs. extrinsic) emotion that impeded associative memory. Unitization encoding improved memory performance in general, accompanied by enhanced recollection process and induction of familiarity process, which is typically not involved in associative memory recognition and was indeed absent in the nonunitization group. Importantly, unitization helped to preserve behavioral performance (specifically, response speed though not recognition strength) from interference by intrinsic emotion while largely reversed the detriment of intrinsic emotion on ERP indices of familiarity and recollection processes. Interestingly, a synergy between intrinsic emotion and unitization encoding was observed, which could underpin the facilitation of familiarity process in associative recognition of emotional pairs. Overall, current findings highlight interference by intrinsic emotion in associative memory, which is nonetheless responsive to mitigation by unitization encoding.

Much is still unknown about the potential long-term effects of prenatal methadone and buprenorphine exposure. We examined neural correlates of cognitive control in 19 prenatally methadone and buprenorphine exposed and 21 nondrug exposed children, aged 9-11 years. Children performed a modified version of the Eriksen Flanker task, which taps into selective attention, conflict response, and response inhibition mechanisms. We investigated behavioral responses and the ERP components N1, P2, N2, P3, and the late positive component (LPC). Children in the exposed group showed normal cognitive control function. However, an atypical ERP response related to perceptual and attention allocation processes was found in the exposed group.

The primary objective of the present study was to verify whether the differences in imagined timbre are reflected by the event-related potentials (ERPs). It was verified the hypotheses that imagining of sounds, varying in spectral characteristics of timbre, influence the amplitude of the late positive component (LPC), associated with auditory imagery-related processes. It was also verified whether the manipulation of the perceived timbre corresponds to the amplitude fluctuations of the auditory evoked potentials (AEPs) N1 and P2. Also, it was expected that the amplitudes of the LPC, N1 and P2 components depend on musical expertise. Musicians and non-musicians took part in two experiments, each of which involved timbre manipulation in term of one parameter of the sound spectrum - spectral centroid or spectral irregularity. Each experiment consisted of auditory perception task followed by auditory imagery training and auditory imagery task. The present study showed that differences in perceived timbre associated with spectral centroid and spectral irregularity are reflected by fluctuations in the amplitude of the N1 and P2 potentials. Perceived differences in spectral centroid are sufficiently distinctive that generation of auditory images of sounds differing in this property induces changes in the amplitude of the late positive component (LPC), recorded during auditory imagery. This means that the LPC is sensitive to changes in the timbre of the imagined sound. Musicians are more accurate in performing auditory imagery task related to timbre than non-musicians. However, musical expertise does not affect the amplitude of the N1, P2 and LPC potentials.

The present study aimed to provide electrophysiological evidence about acquiring complex numerical rules when unexpected numbers were presented. Hence, we compared the neural correlates underlying the acquisition of unexpected complex rules (e.g., 12, 14, 18, 24) compared to expected simple rules (e.g., 12, 14, 16, 18). The event-related potential (ERP) results for the rule acquisition process for the third numbers showed that, in contrast to expected simple rules, unexpected complex rules elicited: an enhanced N200, reflecting the detection of a conflict between the expected numbers and the displayed numbers; a decreased P300, indicating a feeling of uncertainty accompanied by identifying numerical regularity; and an increased LPC, reflecting the working-memory updating caused by expectancy violation and rule acquisition. These results describe the precise time course of acquiring novel and complex rules when unexpected numbers were presented.

Developmental dyslexia is a reading disorder that is associated with deficits in phonological processing, where the exact neural basis for those processing deficits remains unclear. In particular, disagreement exists whether degraded phonological representations or an impaired access to the phonological representations causes these deficits. To investigate this question and to trace changes in neurophysiology during the process of reading acquisition, we designed a longitudinal study with event related potentials (ERPs) in children between kindergarten and second grade. We used an explicit word processing task to elicit the late positive component (LPC), which has been shown to reflect phonological processing. A brain-wide analysis of the LPC with an electrode-wise application of mixed effects models showed significantly attenuated amplitudes in the left temporo-parietal region in dyslexic children. Since these differences were only present in the word and not in the picture (i.e. control) condition, the attenuated amplitudes might reflect impaired access to the phonological representations of words. This was further confirmed by the longitudinal development, which showed a rapid increase in amplitude at the beginning of reading instruction and a decrease with continuing automatization, possibly pointing to a progression from grapheme-phoneme parsing to whole word reading. Our longitudinal study provides the first evidence that it is possible to detect neurophysiological differences in the LPC between children with dyslexia and control children in both preliterate and very early stages of reading acquisition, providing new insights about the neurophysiological development and a potential marker of later reading problems., Graphical abstract Image 1, Highlights • First longitudinal study of the late positive component (LPC) • Left temporo-parietal LPC differs between control and dyslexic children. • LPC increase at reading acquisition and decrease with automatization in typical readers. • Dyslexic children do not show this neurophysiological course of development. • Findings might indicate an impaired access to phonological representations.

Individual differences in dimensions of impulsivity personality including disinhibition and sensation seeking modulate approach responses to reinforcing stimuli, such as drugs and money. The current study examined the effects of monetary incentive on both behavioral performance and electrophysiological activity among individuals varying in disinhibition and sensation seeking. The monetary incentive delay (MID) task was completed under electroencephalogram (EEG) recording. Behavioral data showed that higher disinhibition and sensation-seeking were associated with lower performance accuracy. Event-related potential (ERP) data showed that high reinforcement cues elicited a larger late positive component (LPC) than other conditions among high disinhibition participants, indicating its strong emotional influence. Additionally, in the neutral incentive condition, the feedback-related negativity (FRN) elicited by correct outcomes was larger than that elicited by incorrect outcomes in the high disinhibition group, only. This novel finding indicates that high disinhibition participants were less likely to expect correct outcomes compared to incorrect outcomes in the neutral incentive condition. Finally, the P3 component elicited by outcome presentation showed an interaction between two impulsivity dimensions; when disinhibition level was low, the P3 was larger among high than low sensation seeking participants.

Previous studies have found that competitive Scrabble expertise is associated with enhanced performance on visual lexical decision tasks (LDT), particularly for vertically presented stimuli. In the current study, we investigated the underlying mechanisms responsible for this vertical fluency. We examined behaviour and neural activity during LDT in 19 competitive Scrabble players and 18 matched controls. Using event related potentials (ERP), we investigated whether Scrabble expertise modulates the N170, P300, and late positive component (LPC), associated with visual-orthographic processing, working memory, and stimulus classification, respectively. Behavioural results replicated those from previous studies: Scrabble experts were significantly faster than controls to respond to vertical stimuli in LDT. ERP results showed Scrabble experts had larger P300 amplitudes in right parietal electrodes compared to controls, as well as greater differentiation in LPC amplitudes between vertical words and nonwords. These findings suggest that the mechanism underlying vertical fluency in Scrabble experts involves enhanced domain-specific working memory and stimulus classification processes. The results have implications for understanding the flexibility of the adult visual word recognition system, as well as the behavioural and neural consequences of training within this system.

Part of musical understanding and enjoyment stems from the ability to accurately predict what note (or one of a small set of notes) is likely to follow after hearing the first part of a melody. Selective violation of expectations can add to aesthetic response but radical or frequent violations are likely to be disliked or not comprehended. In this study we investigated whether a lifetime of exposure to music among untrained older adults would enhance their reaction to unexpected endings of unfamiliar melodies. Older and younger adults listened to melodies that had expected or unexpected ending notes, according to Western music theory. Ratings of goodness-of-fit were similar in the groups, as was ERP response to the note onset (N1). However, in later time windows (P200 and Late Positive Component), the amplitude of a response to unexpected and expected endings was both larger in older adults, corresponding to greater sensitivity, and more widespread in locus, consistent with a dedifferentiation pattern. Lateralization patterns also differed. We conclude that older adults refine their understanding of this important aspect of music throughout life, with the ability supported by changing patterns of neural activity.

The aim of the present study was to investigate whether age-related brain response alterations during sentence comprehension exist when verbal fluency and intelligence are controlled for. Twenty-four younger and twenty-four older adults with matched verbal fluency, verbal intelligence, years of education, and gender ratio were recruited. They were asked to read congruent (CON) and incongruent (INCON) sentences to make semantic acceptability judgments. A significant group by condition interaction on accuracy was found, showing a significant congruency effect in younger, but not older adults. The ERP results revealed a dynamic temporal-spatial change in older adults. The congruency related N400 effect was reduced and delayed significantly in the older adults compared to the younger adults, and accompanied by different distribution patterns across time windows. The late positive component with more positive-going in the INCON condition than the CON condition was found in older adults only, which did not correlate with the performance, however. The results suggest that with age, there is a decline in semantic processing during sentence comprehension.

The dynamics of brain activation reflecting attractiveness in humans are unclear. Among the different features affecting attractiveness of the female body, the waist-to-hip ratio (WHR) is considered to be crucial. To date, however, no event-related potential (ERP) study has addressed the question of its associated pattern of brain activation. We carried out two different experiments: (a) a behavioural study, to judge the level of attractiveness of female realistic models depicting 4 different WHRs (0.6, 0.7, 0.8, 0.9) with and without clothes; (b) an EEG paradigm, to record brain activity while participants (heterosexual men and women) viewed these same models. Behavioural results showed that WHRs of 0.7 were considered more attractive than the others. ERP analyses revealed a different pattern of activation for male and female viewers. The 0.7 ratio elicited greater positivity at the P1 level in male viewers but not females. Naked bodies increased the N190 in both groups and peaked earlier for the 0.7 ratio in the male viewers. Finally, the late positive component (LPC) was found to be greater in male than in female viewers and was globally more marked for naked bodies as well as WHRs of 0.7 in both groups of viewers. These results provide the first electrophysiological evidence of specific time periods linked to the processing of a body feature denoting attractiveness and therefore playing a role in mate choice.

The parietal lobe is important for successful recognition memory, but its role is not yet fully understood. We investigated the parietal lobes’ contribution to immediate paired-associate memory and delayed item-recognition memory separately for hits (targets) and correct rejections (distractors). We compared the behavioral performance of 56 patients with known parietal and medial temporal lobe dysfunction (i.e. early Alzheimer's Disease) to 56 healthy control participants in an immediate paired and delayed single item object memory task. Additionally, we performed voxel-based morphometry analyses to investigate the functional-neuroanatomic relationships between performance and voxel-based estimates of atrophy in whole-brain analyses. Behaviorally, all participants performed better identifying targets than rejecting distractors. The voxel-based morphometry analyses associated atrophy in the right ventral parietal cortex with fewer correct responses to familiar items (i.e. hits) in the immediate and delayed conditions. Additionally, medial temporal lobe integrity correlated with better performance in rejecting distractors, but not in identifying targets, in the immediate paired-associate task. Our findings suggest that the parietal lobe critically supports successful immediate and delayed target recognition memory, and that the ventral aspect of the parietal cortex and the medial temporal lobe may have complementary preferences for identifying targets and rejecting distractors, respectively, during recognition memory.

Presenting events in a rhythm has been shown to enhance perception and facilitate responses for stimuli that appear in synchrony with the rhythm, but little is known about how rhythm during encoding influences later recognition. In this study, participants were presented with images of everyday objects in an encoding phase before a recognition task in which they judged whether or not objects were previously presented. Blockwise, object presentation during encoding followed either a rhythmic (constant, predictable) or arrhythmic (random, unpredictable) temporal structure, of which participants were unaware. Recognition was greater for items presented in a rhythmic relative to an arrhythmic manner. During encoding, there was a differential neural activity based on memory effect with larger positivity for rhythmic over arrhythmic stimuli. At recognition, memory-specific ERP components were differentially affected by temporal structure: The FN400 old/new effect was unaffected by rhythmic structure, whereas the late positive component old/new effect was observed only for rhythmically encoded items. Taken together, this study provides new evidence that memory-specific processing at recognition is affected by temporal structure at encoding.

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.

Retrieval practice effect refers to better long-term retention enhanced by active retrieval compared to re-studying, which has been widely demonstrated. However, controversies remain as to whether the underlying mechanism of this effect could be attributed to semantic elaboration. We investigated whether retrieval practice and elaboration were equivalent by observing the underlying cognitive processes of the two conditions using corresponding event-related potentials measures of associative memory and item memory. Behavioral results showed that retrieval practice induced better associate memory performance than elaborative study. For event-related potential results, an early old/recombined effect (FN400) related to familiarity and a late old/recombined effect (late positive component) related to recollection emerged in the retrieval practice condition, while both were absent in the elaborative study condition. An early recombined/new effect (FN400) appeared in the elaborative study condition, which did not occur in the retrieval practice condition. It could be inferred that retrieval practice promoted the recollection of episodic contexts for later associative memory, while elaborative study strengthened the familiarity of individual item. These findings suggest that retrieval practice and elaboration are two distinctive processes.

Recent event-related brain potential (ERP) experiments have demonstrated parafoveal N400 expectancy and congruity effects, showing that semantic information can be accessed from words in parafoveal vision (a conclusion also supported by some eye-tracking work). At the same time, it is unclear how higher-order integrative aspects of language comprehension unfold across the visual field during reading. In the current study, we recorded ERPs in a parafoveal flanker paradigm, while readers were instructed to read passively for comprehension or to judge the plausibility of sentences in which target words varied in their semantic expectancy and congruity. We directly replicated prior work showing graded N400 effects for parafoveal viewing, which are then not duplicated when the target words are processed foveally. Critically, although N400 effects were not modulated by task goals, a posteriorly distributed late positive component thought to reflect semantic integration processes was observed to semantic incongruities only in the plausibility judgment task. However, this effect was observed at a considerable delay, appearing only after words had moved into foveal vision. Our findings thus suggest that semantic access can be initiated in parafoveal vision, whereas central foveal vision may be necessary to enact higher-order (and task-dependent) integrative processing.

Previous studies have reported that observation pressure and outcome pressure impact working memory, but have not investigated whether they exert different effects on working memory. The neuronal activity in some brain areas encodes task-related information corresponding to working memory across delay periods. Therefore, changes in working memory under pressure can be further verified by exploring neuronal activity changes in brain areas under pressure. In this study, we used an N-back task and event-related potentials to explore whether the two types of pressure exert different effects on working memory. The electrophysiological results revealed that observation pressure-induced P1, P2 and late positive component amplitudes are significantly larger than corresponding outcome pressure-induced amplitudes, and the P3 amplitude induced by low-load working memory is significantly larger than that in the high-load condition. A possible explanation is that observation pressure increases attention focus, whereas outcome pressure increases attention dispersion, and a greater memory load results in more information that must be maintained and updated in working memory. These findings indicate that observation pressure and outcome pressure exert different effects on working memory.

Spaced learning has been shown consistently to benefit memory compared with massed learning, yet the neural representations and processes underlying the spacing effect are still poorly understood. In particular, two influential models (i.e., the encoding variability hypothesis and the study-phase retrieval hypothesis) could both model behavioral performance very well, but they make opposite hypotheses regarding the spacing effect's neural mechanisms. The present study attempted to provide empirical neural evidence to adjudicate these competing hypotheses. Using spatiotemporal pattern similarity (STPS) analysis of EEG data, this study investigated whether and how repetition lags (massed/short-spaced/long-spaced) modulated the STPS's contribution to episodic memory encoding in male and female human participants. The results revealed that greater item-specific STPS in the right frontal electrodes at 543–727 ms after stimulus onset was associated with better memory performance. More importantly, this STPS was larger under the spaced-learning condition than the massed-learning condition and partially mediated the spacing effect on memory performance. In addition, we found that massed learning was associated with stronger repetition suppression in the N400 component that reflected momentary retrieval strength, but reduced activity in the late positive component that was associated with memory retrieval. These results suggest that spaced learning improves long-term memory by increasing retrieval effort and enhancing the pattern reinstatement of prior neural representations, which may be achieved by reducing the momentary retrieval strength as the extended repetition lags might help to eliminate the residual representation in working memory. SIGNIFICANCE STATEMENT As one of the most ubiquitous and fundamental phenomena in the history of memory research, the spacing effect provides an important window into understanding how enduring memory is formed in the brain and how different practice strategies could modulate these mechanisms to affect memory performance. By leveraging the neural representational analysis on scalp EEG data, the current study provides the first empirical data to show that spaced learning enhances memory by improving the spatiotemporal similarity that occurs at a late time window. Our results support the study-phase retrieval hypothesis but not the encoding variability hypothesis and emphasize the role of neural pattern reinstatement in strengthening memory via repeated study.

Prior work using word stimuli has uncovered evidence that encoding focus (i.e., self-focus or other-focus) alters non-diagnostic recollection and the putative ERP correlate of recollection (i.e., the Late Positive Component or LPC; Leynes and Mok, 2017, Brain & Cognition). The present study examined the generality of these effects by testing memory for actions. Participants viewed videos of either a male actor or female actor completing simple actions (e.g., Ride the Elevator; Climb the Stairs). Participants judged how much fun it would be to personally perform the action under the self-focus encoding condition, whereas they rated how much fun the actor had while performing the action in the other-focus encoding condition. At test, participants made source judgments regarding who (i.e., male or female) performed the action. Self- and other-focus encoding had similar effects on all behavioral measures including parameters from Dual Process Signal Detection and Unequal Variance Signal Detection models. Experiment 2 recorded brain activity (event-related potentials) and found that self- and other-focus encoding produced similar recognition and LPC amplitudes. These results suggest that encoding focus did not affect the amount of non-diagnostic recollection because both action types promoted strong recollection. Such results are additional evidence that action memory creates more complex traces as compared with typical lab-based stimuli (i.e., pictures or words) and identifies an important boundary condition for encoding focus effects on recollection.

Overweight or obesity can be accompanied by abnormalities in executive function and related neural markers. The aim of the present study was to investigate the behavioral and neural correlates of food-related decision-making in overweight and normal-weight adults. We used a delayed discounting task (DDT), which requires participants to choose between smaller immediate rewards and larger delayed rewards. In total, 24 overweight adults and 24 normal-weight adults participated; all participants engaged with a food-related DDT, and their responses were measured using event-related potentials (ERPs). In the current study, we take the area under the curve (AUC), number of smaller immediate rewards, and reaction times (RTs) as behavioral indicators of DDT. AUC is an individual's discounting rate, with smaller AUC reflecting more impulsive decision-making. Number of smaller immediate rewards also reflects impulsivity. For ERPs, N2, reward-related positivity, P3, and late positive component (LPC) were investigated. Behavioral results showed smaller AUC, more choice of smaller immediate rewards, and longer RTs in overweight adults than in normal-weight adults. Neural markers showed that overweight adults elicited greater N2 in larger delayed rewards than in smaller immediate rewards and also elicited greater reward-related positivity than normal-weight adults. Moreover, the P3 and LPC mean amplitudes of overweight adults were greater than those of normal-weight adults. Pearson correlation analysis showed that body mass index (BMI) was positively related to P3 and LPC, while AUC was negatively related to P3. The findings thus suggest that overweight adults are more impulsive than normal-weight adults. Moreover, overweight adults might experience more cognitive conflict before their reaction, and they might allocate more cognitive resources to food-related stimuli and might have higher-order cognitive processes more involved in motivation or emotion regarding food-related stimuli. This is the first study investigating ERP correlates of food-related decision-making in overweight adults, and it enriches the theoretical models by providing neural markers for future study.

How do bilinguals freely switch languages in daily life (i.e., voluntary language switching)? Does this involve inhibition of cross-language interference, or does easier lexical access to specific words directly trigger switches to another language? To reveal the underlying mechanism of voluntary language switching, the current study applied transcranial direct current stimulation (tDCS) over the right dorsolateral prefrontal cortex (rDLPFC), an area associated with inhibitory control, to investigate whether and how inhibitory control is involved in voluntary language switching. Interestingly, during the A-tDCS and C-tDCS sessions, bilinguals showed faster naming latencies in repeat trials compared to switch trials, indicating a switch cost. Moreover, the cathodal stimulation exhibited a larger LPC in switching to L2 compared to switching to L1. In contrast, the S-tDCS (sham) session showed no switch cost, faster switch naming latencies compared to the A-tDCS and C-tDCS sessions, and little differences in LPC between switch and repeat trials. Together, these findings suggest that modulating inhibition-related brain regions interferes with voluntary language switching.

The capacity to pay attention is important for the cognitive ability, for example, evaluating an object for its qualities. Attention can selectively prioritize the neural processes that are relevant to a given task. Neuroimaging investigations on human attention are primarily focused on vision to the exclusion of other sensory systems, particularly olfaction. Neural underpinnings of human olfactory attention are still not clearly understood. Here, we combined electroencephalographic measurements of olfactory event related potential with electrical neuroimaging to investigate how the neural responses after inhaling the same odor differ between conditions with varying levels of attention, and, in which brain areas. We examined the neural responses when participants attended to a rose-like odor of phenylethyl alcohol for evaluating its pleasantness versus its passive inhalation. Our results gathered significant evidence for attentional modulation of the olfactory neural response. The most prominent effect was found for the late positive component, P3, of olfactory event related potential within a second from the odor onset. The source reconstruction of this data revealed activations in a distributed network of brain regions predominantly in inferior frontal cortex, insula, and inferior temporal gyrus. These results suggest that the neuronal modulations from attention to olfactory pleasantness may be subserved by this network.

The type of threat shown in an image influences the emotional salience of unpleasant images. Seventy-four participants (21 male) rated high threat, moderate threat, and neutral images featuring reptiles, firearms, or humans as electroencephalographic activity was recorded. The magnitude of P3b amplitudes coincided with the threat level of firearm and human images, whereas scenes of attacking snakes and aimed handguns evoked more positive late positive component (LPC) activity than non-attacking or neutral versions of these same stimuli. The lateralised early posterior negativity (EPN) in temporal occipital regions was most negative for firearms, followed by reptiles, and then humans, while the midline EPN in occipital regions was most negative for reptiles, followed by firearms, and then humans. These findings imply late event-related potential positivity is influenced by social relevance (the P3b) or the level of aggression displayed by the stimulus (the LPC), whereas stimulus type may be indexed by EPN modulation.

In music, harmonic syntactic structures are organized hierarchically through local and long-distance dependencies. This study investigated whether congenital amusia, a neurodevelopmental disorder of pitch perception, is associated with impaired processing of harmonic syntactic structures. For stimuli, we used harmonic sequences containing two phrases, where the first phrase ended with a half cadence and the second with an authentic cadence. In Experiment 1, we manipulated the ending chord of the authentic cadence to be either syntactically regular or irregular based on local dependencies. Sixteen amusics and 16 controls judged the expectedness of these chords while their EEG waveforms were recorded. In comparison to the regular endings, irregular endings elicited an ERAN, an N5, and a late positive component in controls but not in amusics, indicating that amusics were impaired in processing local syntactic dependencies. In Experiment 2, we manipulated the half cadence of the harmonic sequences to either adhere to or violate long-distance syntactic dependencies. In response to irregular harmonic sequences, an ERAN-like component and an N5 were elicited in controls but not in amusics, suggesting that amusics were impaired in processing long-distance syntactic dependencies. Furthermore, for controls, the neural processing of local and long-distance syntactic dependencies was correlated at the later integration stage but not at the early detection stage. These findings indicate that amusia is associated with impairment in the detection and integration of local and long-distance syntactic violations. The implications of these findings in terms of hierarchical music-syntactic processing are discussed.

This study examined how different forms of decision-making modulate time perception. Participants performed temporal bisection and generalization tasks, requiring them to either categorize a stimulus duration as more similar to short or long standards (bisection), or identify whether or not a duration was the same as a previously-presented standard (generalization). They responded faster in the bisection task than in the generalization one for long durations. This behavioral effect was accompanied by modulation of event-related potentials (ERPs). More specifically, between 500 ms and 600 ms after stimulus offset, a late positive component (LPC), appearing in the centro-parietal region, showed lower amplitude in the bisection task than in the generalization one, for long durations, mirroring the behavioral result. Before (200–500 ms) and after (600–800 ms) this window, the amplitude of the LPC was globally larger in the generalization paradigm, independently of the presented duration. Finally, the LPC amplitude was higher for long durations than for shorter ones at the beginning of the component (between 200 and 300 ms after stimulus extinction) and was then higher for short durations than for longer ones (between 300 and 600 ms after offset), indicating that the decision about the former stimuli was made earlier than for the latter ones. Taken together, these results indicate that the categorization of durations engages fewer cognitive resources than their identification.

Across languages, lexical frequency and age of acquisition (AoA) are important predictors of word reading that are naturally correlated, and both variables have been shown to interact with phonological regularity. Previous behavioral findings in Chinese have shown stronger regularity effects in low frequency relative to high frequency characters. Meanwhile, the arbitrary mapping hypothesis predicts stronger interference effects in late-acquired irregular words. This study examined the neural bases of these phenomena in Chinese using a delayed naming task with 480 single characters. Single-trial ERP analyses were conducted to contrast the interactions of frequency or AoA effects with phonological regularity, while controlling for the other factor. Results showed differential and significant effects of AoA and frequency at the N400 and late positive component (LPC), respectively, indicating their independence. ERP interaction patterns of frequency and regularity in Chinese were observed for the first time in the LPC time window and suggested semantic interference from sublexical units during character reading. Interaction of AoA and regularity at the N400 could be explained by the semantic hypothesis but appeared inconsistent with the arbitrary mapping hypothesis.

Research has repeatedly shown that familiar and unfamiliar voices elicit different neural responses. But it has also been suggested that different neural correlates associate with the feeling of having heard a voice and knowing who the voice represents. The terminology used to designate these varying responses remains vague, creating a degree of confusion in the literature. Additionally, terms serving to designate tasks of voice discrimination, voice recognition, and speaker identification are often inconsistent creating further ambiguities. The present study used event-related potentials (ERPs) to clarify the difference between responses to 1) unknown voices, 2) trained-to-familiar voices as speech stimuli are repeatedly presented, and 3) intimately familiar voices. In an experiment, 13 participants listened to repeated utterances recorded from 12 speakers. Only one of the 12 voices was intimately familiar to a participant, whereas the remaining 11 voices were unfamiliar. The frequency of presentation of these 11 unfamiliar voices varied with only one being frequently presented (the trained-to-familiar voice). ERP analyses revealed different responses for intimately familiar and unfamiliar voices in two distinct time windows (P2 between 200–250 ms and a late positive component, LPC, between 450–850 ms post-onset) with late responses occurring only for intimately familiar voices. The LPC present sustained shifts, and short-time ERP components appear to reflect an early recognition stage. The trained voice equally elicited distinct responses, compared to rarely heard voices, but these occurred in a third time window (N250 between 300–350 ms post-onset). Overall, the timing of responses suggests that the processing of intimately familiar voices operates in two distinct steps of voice recognition, marked by a P2 on right centro-frontal sites, and speaker identification marked by an LPC component. The recognition of frequently heard voices entails an independent recognition process marked by a differential N250. Based on the present results and previous observations, it is proposed that there is a need to distinguish between processes of voice “recognition” and “identification”. The present study also specifies test conditions serving to reveal this distinction in neural responses, one of which bears on the length of speech stimuli given the late responses associated with voice identification.

Schizophrenia is characterised by significant episodic memory impairment that is thought to be related to problems with encoding, however the neuro-functional mechanisms underlying these deficits are not well understood. The present study used a subsequent recognition memory paradigm and event-related potentials (ERPs) to investigate temporal aspects of episodic memory encoding deficits in schizophrenia.Electroencephalographic data was recorded in 24 patients and 19 healthy controls whilst participants categorised single words as pleasant/unpleasant. ERPs were generated to subsequently recognised versus unrecognised words on the basis of a forced-choice recognition memory task. Subsequent memory effects were examined with the late positive component (LPP). Group differences in N1, P2, N400 and LPP were examined for words correctly recognised.Patients performed more poorly than controls on the recognition task. During encoding patients had significantly reduced N400 and LPP amplitudes than controls. LPP amplitude correlated with task performance however amplitudes did not differ between patients and controls as a function of subsequent memory. No significant differences in N1 or P2 amplitude or latency were observed.The present results indicate that early sensory processes are intact and dysfunctional higher order cognitive processes during encoding are contributing to episodic memory impairments in schizophrenia.

This study explored how temporal context influences recognition. In an ERP experiment, subjects were asked to judge whether pictures, presented one at a time, had been seen since the previous appearance of a special reset screen. The reset screen separated sequences of successively presented stimuli and signaled a change in temporal context. A "new-repeat" picture was one that had been seen before but was to be called "new" because it had not appeared since the previous reset screen. New-repeat pictures elicited a more negative FN400 component than did "old" pictures even though both had seen before during the experiment. This suggests that familiarity, as indexed by the FN400, is sensitive to temporal context. An earlier frontopolar old/new effect distinguished pictures that were seen for the first time in the experiment from all other pictures. The late positive component (LPC), which is typically greater for old stimuli, was smaller for new-repeat pictures than for pictures seen for the first time in the experiment. Finally, individual differences in task performance were predicted by the differences in amplitude of P3b that was evoked by the onset of the reset screen.

The neuronal response to hearing a subject's own name (SON) has been often investigated using event-related potential (ERP) or time-frequency analysis, but seldom by a combination of these methods. Using this combination of approaches would allow the relationship between memory processes engaged by SON and the neuronal responses to be studied in more detail. Thus, the present study used both ERP and time-frequency analysis to investigate memory process for SON by comparing the responses to SON and to unfamiliar names. Specifically, the SON condition was compared with two control conditions: repeated unfamiliar names and singly presented unfamiliar names. This experimental design allowed us to determine the differences in memory processes between hearing one's own name and hearing unrelated but repeatedly heard names. ERP analysis showed that SON elicited a late positive component in parietal areas, while unfamiliar names elicited no positivity. Beta power suppression was observed in response to SON at 0.4-0.6s after stimulus onset at right central sites, but not in response to unfamiliar names. These results are indicative of an involvement of episodic memory processes on hearing SON, which corresponds to the recognition of one's own name. Further, the ERP results suggest the presence of a "new" stimulus recognition process that is activated by singly presented unfamiliar names but not by repeated unfamiliar names.

While major depressive disorder has been associated with increased veridical memory for negative information, prior false memory literature has linked high depressive symptoms to increased false memory for negative information. We tested whether these contradictory findings may be due to semantic and emotional cohesion inflating false alarm rates in the most commonly used false memory paradigm - the Deese-Roediger-McDermott (DRM). In Experiment 1, healthy controls and depressive participants completed two emotional false memory tasks: the DRM, using semantically associated words, and an adaptation using orthographically associated words. Participants encoded words associated with neutral or negative critical lures. During subsequent recognition memory testing, errors were greater for negative than neutral semantic critical lures, but the opposite pattern was observed for orthographic critical lures. These findings support that orthographically associated stimuli provide a non-confounded method to test emotional false memory. In Experiment 2, we deployed the orthographic paradigm with simultaneous electroencephalography (EEG) and a state measure of negative mood (Positive and Negative Affective Scale) to better understand neurocognitive components of emotional false memory. Replicating Experiment 1, we found fewer false alarms for negative than neutral novel orthographically associated words. The EEG data showed significant differences in two memory-related event-related potentials: the familiarity-related N400, and the recollection-related late positive component (LPC). N400 amplitudes were larger for true versus false endorsements. For LPC, increasing depressive symptoms predicted greater amplitude differences for true versus false negative items and reduced differences for neutral items. However, increasingly negative mood predicted reduced amplitude differences for negative items, and greater amplitude differences for neutral items. Although depressive symptoms and negative mood state are highly correlated, they may inform differentially influence shifts in memory retrieval strategies, with depressive symptoms predicting reduced false alarms for negative information, and negative mood state predicting increased recollection errors for negative information.

Autobiographical memory (AM) unfolds over time, but little is known about the dynamics of its retrieval. Space-based models of memory implicate the hippocampus, retrosplenial cortex, and precuneus in early memory computations. Here we used transcranial magnetic stimulation (TMS) and magnetoencephalography (MEG) to investigate the causal role of the precuneus in the dynamics of AM retrieval. During early memory search and construction, precuneus stimulation compared to vertex stimulation led to delayed evoked neural activity within 1000 ​ms after cue presentation. During later memory elaboration, stimulation led to decreased sustained positivity. We further identified a parietal late positive component during memory elaboration, the amplitude of which was associated with spatial perspective during recollection. This association was disrupted following precuneus stimulation, suggesting that this region plays an important role in the neural representation of spatial perspective during AM. These findings demonstrate a causal role for the precuneus in early AM retrieval, during memory search before a specific memory is accessed, and in spatial context reinstatement during the initial stages of memory elaboration and re-experiencing. By utilizing the high temporal resolution of MEG and the causality of TMS, this study helps clarify the neural correlates of early naturalistic memory retrieval.

Facial expressions are deeply tied to empathy, which plays an important role during social communication. The eye region is effective at conveying facial expressions, especially fear and sadness emotions. Further, it was proved that subliminal stimuli could impact human behavior. This research aimed to explore the effect of subliminal sad, fearful and neutral emotions conveyed by the eye region on a viewer's empathy for pain using event-related potentials (ERP). The experiment used an emotional priming paradigm of 3 (prime: subliminal neutral, sad, fear eye region information) × 2 (target: painful, nonpainful pictures) within-subject design. Participants were told to judge whether the targets were in pain or not. Results showed that the subliminal sad eye stimulus elicited a larger P2 amplitude than the subliminal fearful eye stimulus when assessing pain. For P3 and late positive component (LPC), the amplitude elicited by the painful pictures was larger than the amplitude elicited by the nonpainful pictures. The behavioral results demonstrated that people reacted to targets depicting pain more slowly after the sad emotion priming. Moreover, the subjective ratings of Personal Distress (PD) (one of the dimensions in Chinese version of Interpersonal Reactivity Index scale) predicted the pain effect in empathic neural responses in the N1 and N2 time window. The current study showed that subliminal eye emotion affected the viewer's empathy for pain. Compared with the subliminal fearful eye stimulus, the subliminal sad eye stimulus had a greater impact on empathy for pain. The perceptual level of pain was deeper in the late controlled processing stage.

Complex reasoning problems are commonly influenced by a combination of top-down and bottom-up conflicts; however, the common and distinct brain responses to the two types of conflicts have remained unclear. Participants were required to identify the hidden rules in a number series completion task, which included identity condition (e.g., 13, 13, 13), perceptual mismatch condition (bottom-up conflict, e.g., 13 13 +≡), and relational mismatch condition (top-down conflict, e.g., 13 13 14). The ERP results showed that (a) both the perceptual and relational mismatch conditions triggered greater P200, N200, P300, and late positive component than the identity condition, reflecting attention reallocation, perceptual template deviations, feelings of uncertainty, and working memory updating, respectively, and (b) smaller N400 and decreased late negative component were found in the relational mismatch condition in contrast to other conditions, which suggested that changing number values violated rule expectancy as top-down conflict. Therefore, multiple strategies were utilized to detect the conflicts underlying complex reasoning problems.

▪ It is difficult to predict whether newly learned information will be retrievable in the future. A biomarker of long-lasting learning, capable of predicting an individual’s future ability to retrieve a particular memory, could positively influence teaching and educational methods. Event-related potentials (ERPs) were investigated as a potential biomarker of long-lasting learning. Prior ERP studies have supported a dual-process model of recognition memory that categorizes recollection and familiarity as distinct memorial processes with distinct ERP correlates. The late positive component is thought to underlie conscious recollection and the frontal N400 signal is thought to reflect familiarity [Yonelinas, A. P. Components of episodic memory: The contribution of recollection and familiarity. Philosophical Transactions of the Royal Society of London, Series B, Biological Sciences, 356, 1363–1374, 2001]. Here we show that the magnitude of the late positive component, soon after initial learning, is predictive of subsequent recollection of anatomical terms among medical students 6 months later. ▪

Embodied theories assign experience a crucial role in shaping conceptual representations. Supporting evidence comes mostly from studies on concrete concepts, where e.g., motor expertise facilitated action concept processing. This study examined experience-dependent effects on abstract concept processing. We asked participants with high and low mathematical expertise to perform a lexical decision task on mathematical and nonmathematical abstract words, while acquiring event-related potentials. Analyses revealed an interaction of expertise and word type on the amplitude of a fronto-central N400 and a centro-parietal late positive component (LPC). For mathematical words, we found a trend for a lower N400 and a significantly higher LPC amplitude in experts compared to nonexperts. No differences between groups were found for nonmathematical words. The results suggest that expertise affects the processing stages of semantic integration and memory retrieval specifically for expertise-related concepts. This study supports the generalization of experience-dependent conceptual processing mechanisms to the abstract domain.