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Alzheimer's disease (AD), a neurodegenerative disorder characterized by progressive cognitive decline, is generally prevalent in elderly people with significant disability and mortality. There is no effective treatment for AD currently, but the early diagnosis might be beneficial for delaying the disease progression. Apart from invasive laboratory tests and expensive neuroimaging examination, the electroencephalography (EEG) and event related potentials (ERPs) have emerged as promising approaches for the early detection of AD as well as mild cognitive impairment (MCI), due to its affordability, noninvasively, and superior temporal resolution. In addition, the recent advent of deep learning architectures further improves the accuracy of AD and MCI diagnosis. This article reviewed the application of EEG signal for the early diagnosis of AD and MCI, especially focusing on ERPs and deep learning. Furthermore, recommendation for further research to recruit the combination of ERP components and deep leaning models in diagnosing AD and MCI was proposed and highlighted. • Typical features of EEG and ERPs in AD and MCI have been repeatedly demonstrated, but the results were inconsistent. • The deep learning architectures greatly improve the accuracy of AD and MCI diagnosis through extracting features from EEG. • The combination of deep leaning and ERP components in the early diagnosis of AD has been highly recommended. [ABSTRACT FROM AUTHOR]

The P3 component (P300, P3b) is considered to be an effective index of attention and categorization processes when elicited in a visual oddball task, specifically reflecting the selection of a rare target item among frequent non-targets. Researchers have proposed that target categorization is guided by representations of target features held in working memory (WM), thus guiding attention and categorization processes to distinguish targets from non-targets. Although WM is theorized to have visuospatial, verbal and executive function components, most studies do not investigate how these WM components contribute to the P3. This study uses an individual differences approach to determine whether correlations between WM capabilities and P3 amplitudes indicate a common underlying cognitive construct. Participants (n = 140) completed an 80/20 visual oddball task to elicit the P3 as well as independent visual working memory (VWM), spatial working memory (SPWM), and executive function (task switching (TS) and digit symbol substitution (DSS)) tests. Results indicated that measures of executive function, DSS and TS, but not VWM or SPWM ability, correlated with and predicted faster task response times and greater P3 amplitudes. RT and WM measures were not correlated with P3 fractional area latencies. These results support context updating theory. Executive function WM availability, whether as a property of the participant's processing system or based on task demands, plays a functional role in the P3 and an important role in efficient visual categorization and goal-directed learning. • The P3 component (P300, P3b) is an index of attention and categorization processes. • Different components of working memory may guide these processes, affecting the P3. • Only individual differences in executive function predict P3 amplitudes. • Properties of participants' processing systems play a functional role in the P3. [ABSTRACT FROM AUTHOR]

We explored the impact of affect on cognitive control as this relates to individual differences in affective instability and substance use. Toward this end, we examined how different dimensions of affective instability interact to predict substance misuse and the effect of this on two event-related potential components, the reward positivity and the late positive potential, which are said to reflect the neural mechanisms of reward and emotion processing, respectively. We recorded the ongoing electroencephalogram from undergraduate students as they navigated two T-maze tasks in search of rewards. One of the tasks included neutral, pleasant, and unpleasant pictures from the International Affective Picture System. Participants also completed several questionnaires pertaining to substance use and personality. A principal components analysis revealed a factor related to affective instability, which we named reactivity. This factor significantly predicted increased substance use. Individuals reporting higher levels of affective reactivity also displayed a larger reward positivity following stimuli with emotional content. The current study uncovered a group of high-risk substance users who were characterized by greater levels of affective reactivity and context-specific increased sensitivity to rewards. These results help to elucidate the complex factors underlying substance use and may facilitate the creation of individually-tailored treatment programs for those struggling with substance use disorders. • We identified a unique factor representing affective reactivity. • Affective reactivity significantly predicted increased substance use. • Reward positivity was larger in emotional contexts for reactive individuals. [ABSTRACT FROM AUTHOR]

Deficits in auditory event-related potentials (ERPs), brain responses to stimuli indexing different cognitive processes, have been demonstrated widely in chronic schizophrenia (SZ) patients though much less is known about these responses across the early course of psychosis. The present study examined multiple ERP components in first episode psychosis (FEP) patients longitudinally and investigated the relationships between ERPs, psychosocial functioning, and clinical features over time. N1, P2, P3a, and P3b ERPs were elicited using a three-stimulus (novelty) auditory oddball paradigm. FEP patients included SZ-spectrum and psychotic bipolar disorder (BD) diagnoses. Data were collected from 41 patients at baseline, 20 patients at 12-month follow-up, 14 at 24-month follow-up, and 29 healthy control subjects. N1 and P2 ERPs were intact across the early stages of psychosis. Baseline P2 was significantly larger in BD than SZ patients. Reduced P3a and P3b ERPs were found in patients followed longitudinally and are stable over time. ERPs tracked distinct aspects of symptomology and medication, though specific associations were inconsistent across time. Baseline P3a amplitude predicted later psychosocial functioning. The pattern of correlations between ERP components in patients differed from controls. Baseline P3a ERP, and PANSS general score were significant and independent predictors of later MCAS functioning at 12-month. Overall, individuals with worse functioning and greater symptomology produced smaller amplitudes. Our results highlight the heterogeneity within the FEP population. Correlation patterns among ERPs are similar between patients and controls. P3a and P3b amplitudes appear to link with higher-order cognitive and psychosocial functioning. • N1 and P2 ERPs are intact across the early stages of psychosis. • Reduced P3a and P3b ERPs are found in early stage of psychosis patients followed longitudinally and are stable over time. • Baseline P3a ERP and PANSS general score are significant and independent predictors of real life functioning a year later. • Individuals with worse functioning and greater symptomology produced smaller ERP amplitudes. [ABSTRACT FROM AUTHOR]

The present investigation explored the relation between the amount of language input and neural responses in English monolingual (N = 18) and Spanish-English bilingual (N = 19) infants. We examined the mismatch negativity (MMN); both the positive mismatch response (pMMR) and the negative mismatch response (nMMR), and identify a relationship between amount of language input and brain measures of speech discrimination for native and non-native speech sounds (i.e., Spanish, English and Chinese). Brain responses differed as a function of language input for native speech sounds in both monolinguals and bilinguals. Monolingual infants with high language input showed nMMRs to their native English contrast. Bilingual infants with high language input in Spanish and English showed pMMRs to both their native contrasts. The non-native speech contrast showed different patterns of brain activation for monolinguals and bilinguals regardless of amount of language input. Our results indicate that phonological representations of non-native speech sounds in bilingual infants are dependent on the phonetic similarities between their native languages. [ABSTRACT FROM AUTHOR]

Background Accurately monitoring one's performance on daily life tasks, and integrating internal and external performance feedback are necessary for guiding productive behavior. Although internal feedback processing, as indexed by the error-related negativity (ERN), is consistently impaired in schizophrenia, initial findings suggest that external performance feedback processing, as indexed by the feedback negativity (FN), may actually be intact. The current study evaluated internal and external feedback processing task performance and test-retest reliability in schizophrenia. Methods 92 schizophrenia outpatients and 63 healthy controls completed a flanker task (ERN) and a time estimation task (FN). Analyses examined the ΔERN and ΔFN defined as difference waves between correct/positive versus error/negative feedback conditions. A temporal principal component analysis was conducted to distinguish the ΔERN and ΔFN from overlapping neural responses. We also assessed test-retest reliability of ΔERN and ΔFN in patients over a 4-week interval. Results Patients showed reduced ΔERN accompanied by intact ΔFN. In patients, test-retest reliability for both ΔERN and ΔFN over a four-week period was fair to good. Conclusion Individuals with schizophrenia show a pattern of impaired internal, but intact external, feedback processing. This pattern has implications for understanding the nature and neural correlates of impaired feedback processing in schizophrenia. [ABSTRACT FROM AUTHOR]

Through Pavlovian conditioning, reward-associated neutral stimuli can acquire incentive salience and motivate complex behaviors. In smokers, cigarette-associated cues may induce cravings and trigger smoking. Understanding the brain mechanisms underlying conditioned responses to cigarette-associated relative to other inherently pleasant stimuli might contribute to the development of more effective smoking cessation treatments that emphasize the rehabilitation of reward circuitry. Here we measured brain responses to geometric patterns (the conditioned stimuli, CSs) predicting cigarette-related, intrinsically pleasant and neutral images (the unconditioned stimuli, USs) using event-related potentials (ERPs) in 29 never-smokers, 20 nicotine-deprived smokers, and 19 non-deprived smokers. Results showed that during US presentation, cigarette-related and pleasant images prompted higher cortical positivity than neutral images over centro-parietal sensors between 400 and 800 ms post-US onset (late positive potential, LPP). The LPP evoked by pleasant images was significantly larger than the LPP evoked by cigarette images. During CS presentation, ERPs evoked by geometric patterns predicting pleasant and cigarette-related images had significantly larger amplitude than ERPs evoked by CSs predicting neutral images. These effects were maximal over right parietal sites between 220 and 240 ms post-CS onset and over occipital and frontal sites between 308 and 344 ms post-CS onset. Smoking status did not modulate these effects. Our results show that stimuli with no intrinsic reward value (e.g., geometric patterns) may acquire rewarding properties through repeated pairings with established reward cues (i.e., cigarette-related, intrinsically pleasant). [ABSTRACT FROM AUTHOR]

A rapid neural adaptation procedure and Event Related Potentials (ERPs) were employed to study individual differences in Good and Bad recognizers in face perception. The major goal was to characterize the sensitivity of the P100 and the N170 to the identity repetition effect as a function of inter-individual perceptual abilities. For these purposes an integrated methodological approach was used in which a self-report, a standardized test and behavioral performances were combined with ERPs measures. Specifically, two groups of face recognizers (Good and Bad recognizers) were selected by means of a self-report questionnaire on face recognition abilities (The Italian Face Abilities Questionnaire) and the scoring at the Cambridge Face Memory Test. The P100 showed an early neural tuning for faces in Good recognizers. The N170 triggered by the adaptor showed face specificity compared to cars but, importantly, only Good recognizers showed a decreased amplitude of N170 for test faces of the same identity compared to test faces of different identity while this was not the case for Bad recognizers. These results show that ERPs are a suitable and sensitive tool to tap individual differences in face recognition. In conclusion, our results show the importance of considering inter-individual different perceptual abilities in face processing research. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to examine the influence of pediatric sport-related concussion on brain and cognitive function. To do so, we used a between-participants design, measures of executive control, and event-related potentials (ERPs). The findings demonstrate that children with a history of concussion exhibit behavioral deficits in attention, working memory and impulse control, as well as neuroelectric alterations in ERP indices of visual attention (N1), conflict resolution (N2) and attentional resource allocation (P3). Furthermore, the age at injury related to the magnitude of several concussion-related deficits. Accordingly, a single sports-related concussive incident during childhood (m = 2.1 years prior to testing) may lead to subtle, yet pervasive alterations in the behavioral and neural indices of attention and executive control, and age at injury may moderate injury outcomes. [ABSTRACT FROM AUTHOR]

This study investigated the subjective visual acuity by recording ERPs elicited by task-irrelevant visual changes. Optotypes stimuli were presented in the center of the visual field at three threshold levels (supra-threshold, threshold and sub-threshold) while participants were listening to stories. The results showed that neither vMMN nor P3a component was elicited by optotypes stimuli on the sub-threshold condition, whereas, vMMN was elicited under supra-threshold and threshold conditions, with no significant differences between those vMMN amplitudes of two conditions. The P3a amplitude was larger for supra-threshold condition than that for threshold condition. These data demonstrated that the emergence of vMMN could only reflect the automatic detection of orientation-changes in the supra-threshold and threshold conditions compared to the sub-threshold condition, whereas the P3a amplitude could reflect the difference in processing of supra-threshold and threshold stimuli. [ABSTRACT FROM AUTHOR]

Most high-level auditory functions require one to detect the onset and offset of sound sequences as well as registering the rate at which sounds are presented within the sound trains. By recording event-related brain potentials to onsets and offsets of tone trains as well as to changes in the presentation rate, we tested whether these fundamental auditory capabilities are functional at birth. Each of these events elicited significant event-related potential components in sleeping healthy neonates. The data thus demonstrate that the newborn brain is sensitive to these acoustic features suggesting that infants are geared towards the temporal aspects of segregating sound sources, speech and music perception already at birth. [ABSTRACT FROM AUTHOR]

Abstract: The effects of task demands and the interaction between gender and expression in face perception were studied using event-related potentials (ERPs). Participants performed three different tasks with male and female faces that were emotionally inexpressive or that showed happy or angry expressions. In two of the tasks (gender and expression categorization) facial properties were task-relevant while in a third task (symbol discrimination) facial information was irrelevant. Effects of expression were observed on the visual P100 component under all task conditions, suggesting the operation of an automatic process that is not influenced by task demands. The earliest interaction between expression and gender was observed later in the face-sensitive N170 component. This component showed differential modulations by specific combinations of gender and expression (e.g., angry male vs. angry female faces). Main effects of expression and task were observed in a later occipito-temporal component peaking around 230ms post-stimulus onset (EPN or early posterior negativity). Less positive amplitudes in the presence of angry faces and during performance of the gender and expression tasks were observed. Finally, task demands also modulated a positive component peaking around 400ms (LPC, or late positive complex) that showed enhanced amplitude for the gender task. The pattern of results obtained here adds new evidence about the sequence of operations involved in face processing and the interaction of facial properties (gender and expression) in response to different task demands. [Copyright &y& Elsevier]

Abstract: The mechanisms underlying inhibition of return (IOR) are still under debate. Besides the probable implication of several processes in its generation, a reason for this uncertainty may be related to experimental factors affecting the presence, time course, and magnitude of IOR. Two of them may be related to the arrangement of the stimuli in the visual field that could cause possible interactions between IOR and response conflict effects (horizontal arrangements) or between IOR and perceptual asymmetries (vertical arrangement). The purpose of the present study was to explore location and color cueing effects with a vertical arrangement of stimuli, free of S–R compatibility effects. To examine this possibility, a cue-back task with stimuli in the vertical meridian was employed. Targets could randomly and equiprobably appear at cued or uncued locations, or with cued or uncued color. These cueing effects were analyzed on behavior and ERPs separately for upper and lower visual fields (UVF and LVF). Under location cueing, behavioral responses were slower (spatial IOR) in both hemifields. In the ERPs, N1 reductions were observed in both visual fields although with different modulations in their latency and scalp distribution. In the P3 rising beginning, posterior negative deflections in the LVF (Nd) and anterior positive deflections (Pd) in the UVF were observed. Under color cueing, P3 amplitude was reduced in the UVF accompanied by no behavioral effects. These results suggest that different patterns of brain activation can be obtained in upper and lower visual fields under spatial- and non-spatial cueing conditions. [Copyright &y& Elsevier]

Abstract: We have investigated the interplay between face orientation, eye presence, and N170 amplitude by recording Event Related Potentials. To clarify previous reports of nonlinearity in N170 amplitude changes along rotation angle changes, we adopted Itier et al.'s model (Itier et al., 2007) which links N170 face inversion effects with the presence of eyes. Comparison of N170 amplitude and latency for five stimulus categories (Faces-with-eyes, Faces-without-eyes, Eyes, Cars-with-lights, Cars-without-lights) in five different rotations (0, 45, 90, 135, 180) resulted in mixed conclusions. The main findings of this study are as follows: (1) a strong nonlinear relationship between N170 and angle of rotation that is specific to faces, distinguishing face from car category even when no significant differences were observed between these categories for upright and inverted orientations; and (2) the nonlinear relationship between N170 and angle of rotation does not depend on eye presence. We also propose an alternative model according to which N170 amplitude consists of two related aspects of face processing: (A) incompatibility (relative distance of the stimulus pattern from experience-based hypothetical prototype) and (B) integration (degree to which stimulus is integrated into holistic representation), with the former affecting the latter. Moreover, we suggest two possible neural events underlying these two aspects of face processing: neural population size activated by the stimulus, and synchronization within this population. [Copyright &y& Elsevier]

Abstract: Identifying neural mechanisms associated with addiction has substantially improved the overall understanding of addictive processes. Indeed, research suggests that drug-associated cues may take advantage of neural mechanisms originally intended for emotional processing of stimuli relevant to survival. In this study, we investigated cortical responses to several categories of emotional cues (erotic, romance, pleasant objects, mutilation, sadness, and unpleasant objects) as well as two types of smoking-related cues (people smoking and cigarette-related objects). We recorded ERPs from 180 smokers prior to their participation in a smoking cessation clinical trial and assessed emotional salience by measuring the amplitude of the late positive potential (LPP; 400 to 600ms after picture onset). As expected, emotional and cigarette-related pictures prompted a significantly larger LPP than neutral pictures. The amplitude of the LPP increased as a function of picture arousal level, with high-arousing erotic and mutilation pictures showing the largest response in contrast to low-arousing pleasant and unpleasant objects, which showed the smallest response (other than neutral). Compared to females, male participants showed larger LPPs for high-arousing erotic and mutilation pictures. However, unlike emotional pictures, no difference was noted for the LPP between cigarette stimuli containing people versus those containing only objects, suggesting that in contrast to emotional objects, cigarette-related objects are highly relevant for smokers. We also compared the smokers to a small (N=40), convenience sample of never-smokers. We found that never-smokers had significantly smaller LPPs in response to erotic and cigarette stimuli containing only objects compared to smokers. [Copyright &y& Elsevier]

Abstract: Cannabis use has consistently been associated with psychotic symptoms as well as cognitive impairments. Moreover, its use may provoke subclinical psychotic symptoms and is associated with neuropsychological dysfunctions in subjects at ultra high risk (UHR) for developing psychosis. However, to our knowledge, no data are yet available on the relationship between cannabis use, UHR symptoms and information processing as assessed with event related potentials (ERP) in UHR subjects. This cross-sectional study therefore aimed to investigate N100, N200, P200 and P300 ERP components in 48 UHR subjects (19 cannabis users; UHR+C) and 50 healthy controls (21 cannabis users; HC+C). Results showed smaller P300 amplitudes in HC+C and UHR subjects compared to HC−C. Moreover, HC+C showed prolonged P300 and N200 latencies compared to HC−C and UHR−C. No significant ERP differences were found between UHR+C and UHR−C. Regarding the relationship between information processing and psychopathology, we found associations between ERP components and severity of UHR symptoms, findings being most pronounced for N100 latencies and P300 amplitudes and severity of general psychopathology and positive symptoms. We conclude that UHR subjects and healthy cannabis users demonstrate similar P300 amplitude reductions compared to non-using control subjects. In addition, the interrelation of cannabis use with prolonged ERP latencies may signify reduced information processing speed associated with cannabis use. Finally, our findings cautiously support the hypothesis that the clinical phenomena of the UHR state may be associated with abnormalities in stimulus processing. [Copyright &y& Elsevier]

Abstract: The aim of this study was to track recall performance and event-related potentials (ERPs) across multiple trials in a digit-learning task. When a sequence is practiced by repetition, the number of errors typically decreases and a learning curve emerges. Until now, almost all ERP learning and memory research has focused on effects after a single presentation and, therefore, fails to capture the dynamic changes that characterize a learning process. However, the current study used a free-recall task in which a sequence of ten auditory digits was presented repeatedly. Auditory sequences of ten digits were presented in a logical order (control sequences) or in a random order (experimental sequences). Each sequence was presented six times. Participants had to reproduce the sequence after each presentation. EEG recordings were made at the time of the digit presentations. Recall performance for the control sequences was close to asymptote right after the first learning trial, whereas performance for the experimental sequences initially displayed primacy and recency effects. However, these latter effects gradually disappeared over the six repetitions, resulting in near-asymptotic recall performance for all digits. The performance improvement for the middle items of the list was accompanied by an increase in P300 amplitude, implying a close correspondence between this ERP component and the behavioral data. These results, which were discussed in the framework of theories on the functional significance of the P300 amplitude, add to the scarce empirical data on the dynamics of ERP responses in the process of intentional learning. [Copyright &y& Elsevier]

Abstract: Auditory sensory processing is an important element of the neural mechanisms controlling human vocalization. We evaluated which components of Event Related Potentials (ERP) elicited by the unexpected shift of fundamental frequency in a subject''s own voice might correlate with his/her ability to process auditory information. A significant negative correlation between the latency of the N1 component of the ERP and the Montreal Battery of Evaluation of Amusia scores for Melodic organization was found. A possible functional role of neuronal activity underling the N1 component in voice control mechanisms is discussed. [Copyright &y& Elsevier]

Abstract: The study reports neurophysiological and behavioural correlates of lexical decision processes in English speaking dyslexic and non-dyslexic readers. Nine dyslexic adolescents (ages 15.6–17.8) and 9 control (ages 15.4–19.3) adolescents were tested, and the event related potentials (ERPs) to words and pseudowords were recorded simultaneously with behavioural measures. As expected, both groups showed significantly lower accuracy and longer response times for the pseudowords. Furthermore, overall performance (in terms of lower accuracy and longer response times) was significantly worse for the dyslexic group. The ERP analysis indicated that the later positive peaks, P4 (around 400ms from stimulus onset) and P5 (around 500ms), were significantly delayed and attenuated for the dyslexic group. Analysis of the early ERP peaks recorded in the occipitotemporal region led to an interesting dissociation. The controls showed a left lateralised Condition effect, with the amplitude of P1 significantly smaller to words than pseudowords. By contrast, there was no such lexical effect for the dyslexic group, with equal P1 amplitudes for words and pseudowords, at the control level for pseudowords. The deviations in the early ERP components of dyslexics support the evidence of deficits in pre-lexical visual word form recognition within the first 110ms of activation together with altered hemispheric asymmetry. In addition, the slowed and attenuated late ERP components and weaker behavioural performance of the dyslexic group highlight deficits in the later, cognitive, processing stages. [Copyright &y& Elsevier]

Abstract: The aim of this study was to explore whether there were abnormalities of CNV-like and P300-like potentials in stressed rats following repeatedly forced swim stress. Forty male rats were randomly divided into 4 groups: the control groups (Control-1 and Control-2) and the stressed groups (Stress-1 and Stress-2). Rats in stressed groups were administered to repeatedly forced swim 7 or 14 days respectively. Body weight gain, saccharin preference test and open field test were performed. After being anesthetized with urethane, P300-like potentials were evoked by the oddball auditory stimulation and CNV-like potentials were elicited by condition-test stimulus. Results of behavioral tests displayed less body weights and less saccharine solution intake in stressed rats and significant effects of stress on the number of crossing squares, the duration of rearing and the number of grooming in open field test. Prolonged P3 latencies and decreased P3 amplitudes of P300-like potentials were found in the stressed rats. CNV amplitudes were lower in the stressed rats than those in control. Moreover, there were significant correlations between parameters of ERPs (including P3 latency, amplitude and CNV amplitude) and a serial of behavioral traits. This study provides an important evidence of changes of CNV-like and P300-like potentials in depressed rats following repeatedly forced swim stress. Based on this study, ERPs should be taken into consideration and applied as the useful tools in the research work of depressed animal models. [Copyright &y& Elsevier]