Cardiorespiratory fitness, independent of APOE genotype, is associated with better neurocognitive function in older adults: An ERP study.

This study assessed the association between cardiorespiratory fitness and carriage of the apolipoprotein-E ε4 allele (APOE ε4) and cognitive function using behavioral and neuroelectric measures obtained from cognitively normal older adults. A total of 159 adults aged 50-70 years were categorized into four groups based on cardiorespiratory fitness (i.e., higher vs. lower fitness) and APOE genotype (i.e., APOE ε4 carrier vs. non-carrier). Neurocognitive functions were indexed using response time and accuracy measures from the Stroop Test and averaged mean P3 amplitudes of event-related potentials obtained during task performance. A significant main effect of cardiorespiratory fitness (p = .02) and Stroop congruency (p < .001), but not APOE genotype status, with shorter response times for the higher fitness group than for the lower fitness group and for the congruent condition relative to the incongruent condition, were observed. Similar findings were also revealed, with larger averaged mean P3 amplitudes for the higher fitness group than those in the lower fitness group, and in the congruent condition than in the incongruent condition. These findings suggest that higher cardiorespiratory fitness is linked to better neurocognitive function, and the positive association is evident regardless of APOE ε4 status and the cognitive domain assessed in cognitively normal older adults.

Can the Mismatch Negativity Really Be Elicited by Abstract Linguistic Contrasts?

The mismatch negativity (MMN) is an event-related potential component that reflects pre-attentive change detection in the brain. As an electrophysiological index of processing that responds to differences in incoming consecutive stimuli, the MMN can be elicited through, for example, the presentation of two different categories of sounds in an oddball paradigm where sounds from the "standard" category occur frequently and sounds from the "deviant" category occur rarely. The specificity of what can elicit the MMN is yet to be fully defined. Here we test whether the MMN can be generated by an abstract linguistic contrast with no reliable acoustic cue. Previous studies have shown that the way in which an acoustic cue is used to elicit MMN is influenced by linguistic knowledge, but have not shown that a nonacoustic, abstract linguistic contrast can itself elicit MMN. In this study, we test the strongest interpretation of the claim that the MMN can be generated through a purely linguistic contrast by contrasting tenses in ablauting irregular English verbs (where there is no reliable acoustic cue for tense). We find that this contrast elicits a negativity, as do other linguistic contrasts previously shown to elicit MMN (a contrast between phonologically voiced and phonologically voiceless segments and a purely acoustic contrast between aspirated and unaspirated segments). The findings provide evidence that the MMN is indeed sensitive to purely abstract linguistic categories.

Long-term memory formation for voices during sleep in three-month-old infants.

The ability to form long-term memories begins in early infancy. However, little is known about the specific mechanisms that guide memory formation during this developmental stage. We demonstrate the emergence of a long-term memory for a novel voice in three-month-old infants using the EEG mismatch response (MMR) to the word "baby". In an oddball-paradigm, a frequent standard, and two rare deviant voices (novel and mother) were presented before (baseline), and after (test) familiarizing the infants with the novel voice and a subsequent nap. Only the mother deviant but not the novel deviant elicited a late frontal MMR (∼850 ms) at baseline, possibly reflecting a long-term memory representation for the mother's voice. Yet, MMRs to the novel and mother deviant significantly increased in similarity after voice familiarization and sleep. Moreover, both MMRs showed an additional early (∼250 ms) frontal negative component that is potentially related to deviance processing in short-term memory. Enhanced spindle activity during the nap predicted an increase in late MMR amplitude to the novel deviant and increased MMR similarity between novel and mother deviant. Our findings indicate that the late positive MMR in infants might reflect emergent long-term memory that benefits from sleep spindles.

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

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

Investigating Working Memory Deficits in School-Age Children with Attention-Deficit/Hyperactivity Disorder: An Event-Related Potentials Study During Delayed-Match-to-Sample Task.

OBJECTIVE: To investigate the neural mechanisms underlying working memory (WM) deficits in children with ADHD. METHOD: WM was compared between thirty-four children with ADHD and thirty-four matched controls using neuropsychological tests, spatial and verbal versions of modified delayed matching-to-sample (DMTS) tasks, and the event-related potential technique. RESULTS: Children with ADHD demonstrated poor behavioral performance, delayed P3 latencies in high-load spatial modified DMTS tasks during encoding, and delayed P2 and N2 latencies during retrieval in spatial modified DMTS tasks. In high-load verbal modified DMTS tasks during encoding, they showed a smaller P3 amplitude. DISCUSSION: Pronounced deficits in the central executive system in children with ADHD were exhibited by neuropsychological tests and the modified DMTS task. Children with ADHD exhibited a slowing of processing speed during encoding. Under high-load conditions, they showed a reduced P3 amplitude during retrieval, suggesting reduced neural resource allocation was available when the central executive of the working memory was heavily loaded.

Socioeconomic status moderates the relationship between self-esteem and attitudes towards conspicuous consumption: An electrophysiological study.

Research on the impact of self-esteem on conspicuous consumption has shown inconsistent results. This study addresses this variability by examining how socioeconomic status (SES) moderates the relationship between self-esteem and conspicuous consumption. We hypothesized that the relationship varies with SES, predicting a positive relationship at high SES levels and a negative relationship at low SES levels. Our findings confirm this hypothesis. Using a Go/NoGo association task (GNAT) combined with event-related potentials (ERP), we investigated the cognitive processing speeds for congruent and incongruent pairings. This method provided insights into the implicit attitudes towards conspicuous products and revealed the complex dynamics between self-esteem and SES in influencing consumer behavior tendencies. This research advances our understanding of the interactions between self-esteem and SES in conspicuous consumption from an implicit cognitive perspective. It also offers significant practical implications, guiding the development of consumer marketing strategies that can be tailored to different socioeconomic contexts.

Reduced MMN-indexed auditory change detection in a non-clinical high schizotypy sample.

Schizotypal traits include abnormalities in cognition, behavior, and interpersonal relationships that are similar, yet less severe than psychotic symptomology. It is estimated that approximately 5% of the general population displays psychotic symptoms and experiences that can be considered schizotypal in nature, but there is little research examining the neurological correlates of these traits. The mismatch negativity (MMN) event-related potential is an objective measure of auditory change detection derived from electroencephalography. The current study contributes to the limited body of evidence examining the neurobiological underpinnings of schizotypy in a non-clinical sample using the MMN. Participants were recruited from the general population and divided into high and low-schizotypy groups for comparison. Individuals with high schizotypal traits displayed reduced MMN amplitudes in response to frequency and location deviants, and longer MMN latencies in response to location deviants. Specific sub-traits of schizotypy were uniquely related to frequency and location amplitudes, suggesting the previously reported inconsistencies in the literature may be due to diverse samples and differing deviant tone types. Finally, impulsivity and sensation-seeking likely contributed to the slower processing seen in location deviance detection. Ultimately, the current results provide evidence that the neurobiological abnormalities seen in clinical populations of schizotypal personality disorder and psychosis also extend to non-clinical populations.

Individuals with high autism traits show top-down attention bias towards threatening stimuli.

Individuals with autistic traits (AT) are widely distributed in the general population. Strengthening understanding of AT can provide a broader perspective for autism research as well as more accurate diagnosis and personalized treatment plans for clinical practice. Previous studies on attention bias among high-AT individuals have yielded inconsistent results, which may relate to different stages of attention. In this study, we selected two groups with high and low level AT from the general population, and then adopted the odd-one-out search task, combined with Event-related potential (ERP) technique, conducted both attention orientation and attention dissociation tasks, to explore attention bias and electroencephalogram (EEG) characteristics towards threatening emotional faces in these groups. The behavioral data showed no accelerated attention orientation to angry faces and neutral faces; however, there was attention dissociation difficulty for angry faces. Compared with low-AT individuals, the EEG results showed that high-AT individuals have acceleration of attention orientation and attention dissociation difficulty for threatening emotional faces. From the perspective of top-down concept-driven processing, these findings suggest that high-AT individuals have attention bias for cognitive processing of threatening stimuli, which is mainly due to acceleration of attention orientation and attention dissociation difficulties for threatening information.

Does Cognitive Load Affect Measures of Consciousness?

BACKGROUND: Developing and testing methods for reliably measuring the state of consciousness of individuals is important for both basic research and clinical purposes. In recent years, several promising measures of consciousness, grounded in theoretical developments, have been proposed. However, the degrees to which these measures are affected by changes in brain activity that are not related to changes in the degree of consciousness has not been well tested. In this study, we examined whether several of these measures are modulated by the loading of cognitive resources. METHODS: We recorded electroencephalography (EEG) from 12 participants in two conditions: (1) while passively attending to sensory stimuli related to the measures and (2) during increased cognitive load consisting of a demanding working memory task. We investigated whether a set of proposed objective EEG-based measures of consciousness differed between the passive and the cognitively demanding conditions. RESULTS: The P300b event-related potential (sensitive to conscious awareness of deviance from an expected pattern in auditory stimuli) was significantly affected by concurrent performance on a working memory task, whereas various measures based on signal diversity of spontaneous and perturbed EEG were not. CONCLUSION: Because signal diversity-based measures of spontaneous or perturbed EEG are not sensitive to the degree of cognitive load, we suggest that these measures may be used in clinical situations where attention, sensory processing, or command following might be impaired.

Sensori-motor neurofeedback improves inhibitory control and induces neural changes: a placebo-controlled, double-blind, event-related potentials study.

Background/Objective: Inhibition is crucial for controlling behavior and is impaired in various psychopathologies. Neurofeedback holds promise in addressing cognitive deficits, and experimental research is essential for identifying its functional benefits. This study aimed to investigate whether boosting sensorimotor activity (SMR) improves inhibitory control in a final sample of healthy individuals (N = 53), while exploring the underlying neurophysiological mechanism. Method: Participants were randomly divided into two groups: one receiving SMR neurofeedback training to enhance sensorimotor activity within the 12-15 Hz frequency range, and the other receiving sham feedback. Inhibition performance and neural correlates were evaluated with a Go-NoGo task before (T0) and after (T1) 10 neurofeedback sessions using event-related potentials. Data were analyzed via ANOVAs and regression analyses. Results: Compared to placebo, the active group demonstrated higher absolute SMR power (p = 0.040) and improvements in inhibitory control, including faster response times and fewer inhibition errors (p < 0.001, d = 6.06), associated with a larger NoGoP3d amplitude (p < 0.001, d = 3.35). A positive correlation between the increase in SMR power and the rise in NoGoP3d amplitude (ß=0.46, p = 0.015) explains 21 % of the observed variance. Conclusions: Uptraining SMR power is linked to heightened utilization of neural resources for executing optimal inhibition responses. These results uphold its effectiveness in cognitive rehabilitation.

Attention to food stimuli in binge eating disorder: Electrophysiological evidence.

Attentional biases towards food play an important role in the pathology of binge eating disorder (BED). Later stage electrophysiological potentials (P300, late positive potential) present promising markers of motivated attention with high temporal, albeit low spatial resolution. Complementing this, the N2pc is an earlier-latency component providing the possibility of more directly analyzing visuospatial attention. Therefore, we tested a group with BED (N = 60), as well as an overweight (OW; N = 28) and normal weight (NW; N = 30) group without BED in a Go/No-Go paradigm using food and nonfood distractor images. Only the OW group in exclusively the Go trials displayed a stronger spatial attention allocation towards nonfood distractors as evidenced by an increased N2pc amplitude. In the P300's time window, the OW group displayed no attentional bias towards food and the NW group only did so in the absence of a target. Solely the BED group allocated more motivated attention towards food distractors both in Go and No-Go trials. In the following late positive potential (LPP), the OW group exhibited a general attentional bias towards food distractors, while the BED group only did so in the absence of a target. These results are discussed in light of the incentive sensitization theory and a potential early attentional suppression of potent distractors.

Error monitoring under working memory load: An electrocortical investigation.

Error monitoring is essential for detecting errors and may facilitate behavioral adjustments that can reduce or prevent future errors. At times, error monitoring must occur while individuals are engaged in other, cognitively demanding tasks that might consume processing resources necessary for error monitoring. Here, we set out to determine whether concurrent working memory (WM) load interferes with error monitoring, as measured using event-related potentials, the error-related negativity (Ne/ERN), and error positivity (Pe). Fifty-four participants (n = 33 female) completed an arrowhead flanker task, with trials presented under low (2 letter) or high (6 letter) WM load. Participants were required to hold letter strings in memory and to recall these letters at the end of a set of flanker trials. Results showed that WM load reduced the Pe but did not affect the Ne/ERN. Therefore, WM load appeared to attenuate later, more elaborated stages of error processing, though initial error detection was unaffected. Additionally, high WM load slowed reaction times overall, but did not lead to a significant increase in errors. As such, slower responses may have helped participants maintain comparable accuracy for low-load versus high-load trials. Overall, results indicate that WM load interferes with the evaluation of error significance, which could interfere with behavioral adaptations over time.

The mutual influences between working memory and empathy for pain: the role of social distance.

Understanding the mechanisms behind the interaction of empathy for pain (EfP) and working memory (WM), particularly how they are influenced by social factors like perceived social distance (SD), is vital for comprehending how humans dynamically adapt to the complexities of social life. However, there is very little known about these mechanisms. Accordingly, we recruited 116 healthy participants to investigate the bidirectional influence and electrophysiological responses between WM and EfP, including the role of SD. Our research results revealed that the interaction between WM load and SD significantly influenced the processing of EfP. Specifically, high WM load and distant SD facilitated early processing of EfP. Conversely, low WM load and close SD promoted late processing of EfP. Further, the interaction between EfP and SD significantly influenced the performance of ongoing WM tasks. Specifically, the kin's pain, compared to kin's non-pain, improved participant's performance on low WM load tasks; however, it diminished participant's performance on tasks with high WM load. Overall, these results provide evidence at both behavioral and neural levels for the mutual influence of WM and EfP during the same temporal process, and SD emerged as a crucial moderating factor during these mutual influences.

Inhibitory P300 subprocesses and neural compensation in genetic risk for Alzheimer's disease: The case for temporal-spatial principal component analysis.

The P300 event-related potential (ERP) is widely investigated in cognitive neuroscience, including related to aging, with smaller amplitudes and delayed latency consistently reported in Alzheimer's disease (AD). Given that AD-related neurological changes begin years before symptom onset, ERPs in asymptomatic elders with AD risk may characterize early changes. ERPs are seldom studied in this population. Yet, healthy carriers of apolipoprotein-E (APOE) ε4 have evidenced delayed P300 latencies, while P300 amplitude differences are seldom found. However, despite its frequent study, the specific cognitive processes reflected by P300 remain unclear. We propose that these challenges are due to the relatively long P300 window, which likely encompasses multiple underlying subprocesses that overlap in time. Temporal-spatial principal component analysis (tsPCA) maintains the high temporal resolution of EEG and is better suited to isolate processes that overlap in time. Thus, we interrogated APOE ε4 differences in P300 activity during successful stop-signal inhibitory control in healthy, cognitively intact older adults (25 ε4-, 20 ε4+), using both conventional ERP metrics (i.e., mean and peak amplitude) and P300 tsPCA factors. P300 amplitudes did not differ by ε4 using conventional metrics. tsPCA revealed two P300 factors in each ε4 group: first, a Posterior P300 (attention allocation) factor, and second, a relatively Anterior P300 (performance monitoring, evaluating, and updating) factor. tsPCA uniquely revealed greater activity in ε4+ vs. ε4- in Anterior P300. ε4 groups had comparable task performance, suggesting that greater P300 activity in ε4+ likely reflects neural compensation for ε4-related deficits, thereby enabling the maintenance of good task performance.

Right visual field advantage in orientation discrimination is influenced by biased suppression.

Visual input is not equally processed over space. In recent years, a right visual field advantage during free walking and standing in orientation discrimination and contrast detection task was reported. The current study investigated the underlying mechanism of the previously reported right visual field advantage. It particularly tested if the advantage is driven by a stronger suppression of distracting input from the left visual field or improved processing of targets from the right visual field. Combing behavioural and electrophysiological measurements in a mobile EEG and augmented reality setup, human participants (n = 30) in a standing and a walking condition performed a line orientation discrimination task with stimulus eccentricity and distractor status being manipulated. The right visual field advantage, as demonstrated in accuracy and reaction time, was influenced by the distractor status. Specifically, the right visual field advantage was only observed when the target had an incongruent line orientation with the distractor. Neural data further showed that the right visual field advantage was paralleled by a strong modulation of neural activity in the right hemisphere (i.e. contralateral to the distractor). A significant positive correlation between this right hemispheric event related potential (ERP) and behavioural measures (accuracy and reaction time) was found exclusively for trials in which a target was presented on the right and an incongruent distractor was presented on the left. The right hemispheric ERP component further predicted the strength of the right visual field advantage. Notably, the lateralised brain activity and the right visual field advantage were both independent of stimulus eccentricity and the movement state of participants. Overall, our findings suggest an important role of spatially biased suppression of left distracting input in the right visual field advantage as found in orientation discrimination.

Temporal context modulates cross-modality time discrimination: Electrophysiological evidence for supramodal temporal representation.

Although the peripheral nervous system lacks a dedicated receptor, the brain processes temporal information through different sensory channels. A critical question is whether temporal information from different sensory modalities at different times forms modality-specific representations or is integrated into a common representation in a supramodal manner. Behavioral studies on temporal memory mixing and the central tendency effect have provided evidence for supramodal temporal representations. We aimed to provide electrophysiological evidence for this proposal by employing a cross-modality time discrimination task combined with electroencephalogram (EEG) recordings. The task maintained a fixed auditory standard duration, whereas the visual comparison duration was randomly selected from the short and long ranges, creating two different audio-visual temporal contexts. The behavioral results showed that the point of subjective equality (PSE) in the short context was significantly lower than that in the long context. The EEG results revealed that the amplitude of the contingent negative variation (CNV) in the short context was significantly higher (more negative) than in the long context in the early stage, while it was lower (more positive) in the later stage. These results suggest that the audiovisual temporal context is integrated with the auditory standard duration to generate a subjective time criterion. Compared with the long context, the subjective time criterion in the short context was shorter, resulting in earlier decision-making and a preceding decrease in CNV. Our study provides electrophysiological evidence that temporal information from different modalities inputted into the brain at different times can form a supramodal temporal representation.

Blunted sensitivity to expected value during risky decision making in individuals with problematic pornography use.

Background and aims: Neurobiological models of addiction posit that addiction manifests through an amplified salience towards addiction-associated stimuli and a diminished responsiveness to non-addiction-related incentives. However, existing research on reward processing in individuals with problematic pornography use (PPU) has primarily been limited to sexual cue reactivity. Methods: In this event-related potential (ERP) study, we employed a risky decision-making task involving 30 individuals with PPU and 33 healthy controls (HCs) to examine the effects of PPU on non-pornographic (money) reward valuation. Results: Compared to HCs, individuals with PPU exhibited compromised sensitivity to monetary rewards. Specifically, while the HC group demonstrated a differential response in late positive potential (LPP) amplitude to various expected value (EV) levels, this pattern was absent in the PPU group. This impairment was associated with poorer adaptive decision-making, as evidenced by PPU participants' inability to adjust risk choices based on changes in EV, leading to a propensity for riskier decisions in disadvantageous situations. Discussion and conclusions: The findings of impaired monetary evaluation in individuals with PPU may potentially explain why they continually pursue pornographic rewards while showing insensitivity to other rewards in daily life. Consequently, treatment development strategies may prioritize improving sensitivity to non-pornographic rewards within this population.

Alignment of behaviour and tDCS stimulation site induces maximum response: evidence from online tDCS and ERP.

tDCS modulates the activity of the neuronal networks to induce the desired behavioural changes. Two factors determine its effectiveness- (1) whether the network being stimulated is relevant to the task, and (2) if there is a scope for improvement in behavioral performance. To explore this, both dorsal (sub-lexical) and ventral (lexical) reading networks were stimulated (20 min, 2 mA) in 25 healthy young volunteers. Participants performed two reading tasks with different levels of lexical involvement: word fragment completion tasks (WCT) and word association tasks (WAT), while event-related potentials (ERPs) were recorded simultaneously. The study used a within-subject design over three sessions, comparing various electrode montages targeting the dorsal pathway's left inferior parietal lobule or the ventral reading pathway's left middle temporal lobule, as well as sham stimulation. The impact of tDCS sessions (dorsal, ventral, & sham) and task type (WCT & WAT) on priming effects (primed vs. unprimed) of behavioral performance (accuracy and reaction times), and ERP parameters (N400 amplitudes and latencies) were statistically analyzed.It was found that tDCS modulated the performance of WAT only (a task with a lower priming effect). The failure to modulate WCT (larger priming effect) indicated that tDCS was effective for conditions with room for improvement compared to a task where performance has reached the ceiling. Ventral stimulation enhanced accuracy in the WAT condition and shortened the N400 latency of the priming effect. In contrast, dorsal stimulation delayed the priming effect reaction time in the WAT condition and enhanced the N400 amplitude. To conclude, enhancement in performance due to tDCS occurs when the network (ventral) being stimulated aligns with the cognitive demands of the task and there is a scope for improvement.

Modulation of audiovisual integration in the left and right sides: effects of side and spatial coherency.

BACKGROUND: Using event-related potentials (ERPs), we aimed to investigate audiovisual integration neural mechanisms during a letter identification task in the left and right sides. Unimodal (A,V) and bimodal (AV) stimuli were presented on either side, with ERPs from unimodal (A,V) stimuli on the same side being compared to those from simultaneous bimodal stimuli (AV). Non-zero results of the AV-(A + V) difference waveforms indicated audiovisual integration on the left/right side. RESULTS: When spatially coherent AV stimuli were presented on the right side, two significant ERP components in the integrated differential wave were noted. The N134 and N262, present in the first 300 ms of the AV-(A + V) integration difference wave, indicated significant audiovisual integration effects. However, when these stimuli were presented on the left side, there were no significant integration components. This audiovisual integration difference may stem from left/right asymmetry of cerebral hemisphere language processing. CONCLUSIONS: Audiovisual letter information presented on the right side was easier to integrate, process, and represent. Additionally, only one significant integrative component peaked at 140 ms in the parietal cortex for spatially non-coherent AV stimuli and provided audiovisual multisensory integration, which could be attributed to some integrative neural processes that depend on the spatial congruity of the auditory and visual stimuli.