P300 Amplitude Research Articles

Modulation of the neuronal response in human primary visual cortex by re-entrant projections during retinal input processing as manifest in the visual evoked potential

Initial deflections in the visual evoked potential (VEP) reflect the neuronal process of extracting features from the retinal input; a process not modulated by re-entrant projections. Later deflections in the VEP reflect the neuronal process of combining features into an object, a process referred to as ‘object closure’ and modulated by re-entrant projections. Our earlier work indicated that the VEP reflects independent neuronal responses processing temporal – and spatial luminance contrast and that these responses arise from an interaction between forward and re-entrant input. In this earlier work, changing the temporal luminance contrast property of a stimulus altered its spatial luminance contrast property. We recorded the VEP in 12 volunteers viewing image pairs of a windmill, regular dartboard or an RMS dartboard rotated by either Π/4, Π/2, 3Π/4 or Π radians with respect to each other. The windmill and regular dartboard had identical white to black ratio, while the two dartboards identical contrast edges per unit area. Rotation varied temporal luminance contrast of a stimulus without affecting its spatial luminance contrast. N75, P100, N135 and P240 amplitude and latency were compared and a source localisation and temporal frequency analysis performed. P100 amplitude signals a neuronal response processing temporal luminance contrast that is modulated by re-entrant projections with fast axonal conduction velocities. N135 and P240 signal the neuronal response processing spatial luminance contrast and is modulated by re-entrant projections with slow axonal conduction velocities. The dorsal stream is interconnected by fast axonal conduction velocities, the ventral stream by slow axonal conduction velocities.

Neural mechanisms of Chinese character recognition, updating, and maintenance in the N-back task

Using the N-back task, we investigated how memory load influences the neural activity of the Chinese character cognitive subprocess (recognition, updating, and maintenance) in Mainland Chinese speakers. Twenty-seven participants completed the Chinese character N-back paradigm while having their event-related potentials recorded. The study employed time and frequency domain analyses of EEG data. Results showed that accuracy decreased and response times increased with larger N values. For ERPs, N2pc and P300 amplitudes decreased and SW amplitude increased with larger N values. For time frequency analyses, the desynchronization of alpha oscillations decreased after stimulus onset, but the synchronization of alpha oscillations increased during the maintenance phase. The results suggest that greater memory load is related to a decrease in cognitive resources during updating and an increase in cognitive resources during information maintenance. The results of a behavioral-ERP data structural equation model analysis showed that the ERP indicators in the maintenance phase predicted behavioral performance.

ERP evidence for temporal differences between cross-modal and cross-domain analogical reasoning

Previous studies have shown that individuals not only successfully engage in cross-domain analogies but also accomplish cross-modal reasoning. Yet, the behavioral representation and neurophysiological basis of cross-modal and cross-domain analogical reasoning remain unclear. This study established three analogical reasoning conditions by combining a multi-to-multi learning-test paradigm with a four‑term analogy paradigm: within-domain, cross-domain, and cross-modal conditions. Thirty participants were required to judge whether the relationship between C and D was the same as the learned relationship between A and B. Behavioral results revealed no significant differences in reaction times and accuracy between cross-domain and cross-modal conditions, but both conditions showed significantly lower accuracy than within-domain condition. ERP results indicated a larger P2 amplitude in the cross-modal condition, while a larger N400 amplitude was observed in the cross-domain condition. These findings suggest: (1) The P2 in cross-modal analogical reasoning is associated with more difficult access to cross-modal information. (2) The N400 in cross-domain analogical reasoning is related to more challenging semantic processing. This study provides the first evidence of behavioral and ERP differences between cross-modal and cross-domain analogical reasoning, deepening our understanding of the cognitive processes involved in cross-modal analogical reasoning.

Effects of Metrical Context on the P1 Component.

The temporal structure of sound, characterized by regular patterns, plays a crucial role in optimizing the processing of auditory information. The meter, representing a well-organized sequence of evenly spaced beats in music, exhibits a hierarchical arrangement, with stronger beats occupying higher metrical positions. Moreover, the meter has been shown to influence behavioral and neural processing, particularly the N1, P2, and mismatch negativity components. However, the role of the P1 component in the context of metrical hierarchy remains unexplored. This study aimed to investigate the effects of metrical hierarchy on the P1 component and compare the responses between musicians and non-musicians. Thirty participants (15 musicians and 15 non-musicians) were enrolled in the study. Auditory stimuli consisted of a synthesized speech syllable presented together with a repeating series of four tones, establishing a quadruple meter. Electrophysiological recordings were performed to measure the P1 component. The results revealed that metrical position had a significant effect on P1 amplitude, with the strongest beat showing the lowest amplitude. This contrasts with previous findings, in which enhanced P1 responses were typically observed at on-the-beat positions. The reduced P1 response on the strong beat can be interpreted within the framework of predictive coding and temporal prediction, where a higher predictability of pitch changes at the strong beat leads to a reduction in the P1 response. Furthermore, higher P1 amplitudes were observed in musicians compared to non-musicians, suggesting that musicians have enhanced sensory processing. This study demonstrates the effects of metrical hierarchy on the P1 component, thereby enriching our understanding of auditory processing. The results suggest that predictive coding and temporal prediction play important roles in shaping sensory processing. Further, they suggest that musical training may enhance P1 responses.

Disentangling effort from probability of success: Temporal dynamics of frontal midline theta in effort-based reward processing

The ability to weigh a reward against the effort required to acquire it is critical for decision-making. However, extant experimental paradigms oftentimes confound increased effort demand with decreased reward probability, thereby obscuring neural correlates underlying these cognitive processes. To resolve this issue, we designed novel tasks that disentangled probability of success – and therefore reward probability – from effort demand. In Experiment 1, reward magnitude and effort demand were varied while reward probability was kept constant. In Experiment 2, effort demand and reward probability were varied while reward magnitude remained fixed. Electroencephalogram (EEG) data was recorded to explore how frontal midline theta (FMT; an electrophysiological index of mPFC function) and component P3 (an index of incentive salience) respond to effort demand, and reward magnitude and probability. We found no evidence that FMT tracked effort demands or net value during cue evaluation. At feedback, however, FMT power was enhanced for high compared to low effort trials, but not modulated by reward magnitude or probability. Conversely, P3 was sensitive to reward magnitude and probability at both cue and feedback phases and only integrated expended effort costs at feedback, such that P3 amplitudes continued to scale with reward magnitude and probability but were also increased for high compared to low effort reward feedback. These findings suggest that, when likelihood of success is equal, FMT power does not track net value of prospective effort-based rewards. Instead, expended cognitive effort potentiates FMT power and enhances the saliency of rewards at feedback. Significance statementThe way the brain weighs rewards against the effort required to achieve them is critical for understanding motivational disorders. Current paradigms confound increased effort demand with decreased reward probability, making it difficult to disentangle neural activity associated with effort costs from those associated with reward likelihood. Here, we explored the temporal dynamics of effort-based reward (via frontal midline theta (FMT) and component P3) while participants underwent a novel paradigm that kept probability of reward constant between mental effort demand conditions. Our findings suggest that the FMT does not track net value and that expended effort enhances, instead of attenuates, the saliency of rewards.

Food-related inhibitory control deficits in young male adults with obesity: Behavioral and ERP evidence from a food-related go/no-go task

PurposeObesity poses a pervasive challenge to global public health, which is linked to adverse physical health outcomes and cognitive decline. Cognitive function, particularly food-related cognitive function, plays a critical role in sustaining a healthy weight and mitigating the progression of obesity. The aim of this study was to investigate the behavioral and neuroelectronic aspects of food-related inhibitory functions in young adult males with obesity. MethodsForty-nine participants with obesity and healthy-weight were recruited (BMI = 35.83 ± 5.06 kg/m2 vs. 22.55 ± 1.73 kg/m2, age = 24.23 ± 4.55 years vs. 26.00 ± 3.97 years). A food-related Go/No-go task which included 6 distinct blocks in a randomized order was conducted to investigate the general and food-related inhibitory control. 180 stimulus images from the Food Picture Database encompassing high-calorie food, low-calorie food, and neutral images were selected. Behavioral (Go RT, Go ACC, No-go ACC) and event-related potential measures (N2 and P3 amplitude) during the food-related Go/No-go task were measured. ResultsThe main findings indicated that the group with obesity exhibited lower No-go accuracy, slower go reaction times, and smaller P3 amplitudes in high-calorie, low-calorie foods, and neutral picture, compared to the normal-weight group, but with no group difference in N2. Additionally, high-calorie food induced larger N2 and P3 amplitude than the neutral stimuli. ConclusionsYoung male adults with obesity exhibit poorer inhibitory control in both food and non-food domains, specifically in slower reaction time and reduced accuracy, featuring difficulties in neural resource recruitment during the inhibitory control process. Additionally, the P3 component could serve as sensitive indicators to reveal the neural mechanisms of inhibitory control deficits in obesity, while the N2 and P3 components may differentiate the neural differences between high-calorie foods and non-foods in inhibitory control processing. Food, especially high-calorie food, induces more neural resources and may exacerbate the poor inhibitory ability towards food in obesity. Targeted interventions such as exercise interventions, cognitive training as well as neuromodulation interventions are warranted in the future to improve impaired general and food-related inhibitory functions in the obese populations, offering both theoretical and practical frameworks for obesity prevention and treatment.

Exploring the ‘black box’ of anxiety: An ERP study of non-consciously triggered fear generalization

Individuals with anxiety disorders frequently display heightened fear responses, even in situations where there is no imminent danger. We hypothesize that these irrational fear responses are related to automatic processing of fear generalization. The initial automatic detection of stimuli often operates at a non-conscious level. However, whether fear generalization can occur when the cues are not perceived consciously remains unclear. The current study investigated the neurocognitive mechanisms underlying fear conditioning and its non-conscious and conscious generalization using a backward masking paradigm, combined with analysis of event-related potentials from electroencephalographic recordings. Behaviorally, participants showed heightened shock expectancy in response to non-conscious perceived generalization stimuli compared to those perceived consciously. Nonetheless, participants could not consciously distinguish between danger and safe cues in non-conscious trials. Physiologically, danger cues evoked larger frontal N1 amplitudes than safety cues in non-conscious trials, suggesting enhanced attention vigilance towards danger cues in the early sensory processing stage. Meanwhile, when fear generalization was conscious, it was accompanied by a larger P2 amplitude, indicating attention orientation or stimulus evaluation. In addition, fear conditioning was associated with sustained discrimination on P2, P3, and LPP. These findings collectively suggest that non-conscious fear generalization occurs at the neural level, yet additional control conditions are required to confirm this phenomenon on the US expectancy. Thus, non-consciously fear generalization may represent a mechanism that could trigger automatic irrational fear, highlighting the need for further research to explore therapeutic targets in anxiety disorders.

Performance of cognitive tasks and functional brain activity in anxiety disorders

Objective. To improve understanding of psychophysiological underpinnings of anxiety disorders a comprehensive study, that included the analysis of cognitive tasks performance, event-related potentials and psychometric scales, has been conducted.Materials and Methods. Participants were patients with generalized anxiety disorder (GAD group — 12 s.), mixed anxiety and depressive disorder (ADD group — 16 s.) and healthy volunteers (control group — 16 s.). The psychometric techniques included the questionnaires of Spielberger, HADS (Hospital Anxiety and Depression Scale) and Carver-White (BIS/BAS Scale). Psychophysiological methods included antisaccade task (AS) and event-related evoked potentials P300 that were recorded during auditory oddball task.Results. The significantly increased anxiety and depression scales, as well as the decreased BAS Reward Responsiveness scale, was found in patients of both clinical groups compared to control one; the increased BIS scale was revealed only in ADD group. In GAD and ADD groups AS performance was worse in response to stimuli in left hemi-field that are initially processed in right hemisphere; on the contrary, decreased number of target stimuli omissions was found in oddball task in clinical groups. P300 amplitude was larger, and P300 latency was shorter for patients with ADD compared to controls. Analysis of asymmetry demonstrated that P300 amplitudes were greater over the frontal-central right than over the left hemisphere in ADD group.Conclusion. The study demonstrated that anxiety disorders are accompanied by reallocation of attentional resources and changes in functional organization of brain networks involved in attention and executive functions. With the same direction, the shifts were greater in ADD group.

Implications of depressive mood in OSAHS patients: insights from event-related potential

BackgroundObstructive sleep apnea-hypopnea syndrome (OSAHS) is a chronic breathing disorder characterized by recurrent upper airway obstruction during sleep. Although previous studies have shown a link between OSAHS and depressive mood, the neurobiological mechanisms underlying mood disorders in OSAHS patients remain poorly understood. This study aims to investigate the emotion processing mechanism in OSAHS patients with depressive mood using event-related potentials (ERPs).MethodsSeventy-four OSAHS patients were divided into the depressive mood and non-depressive mood groups according to their Self-rating Depression Scale (SDS) scores. Patients underwent overnight polysomnography and completed various cognitive and emotional questionnaires. The patients were shown facial images displaying positive, neutral, and negative emotions and tasked to identify the emotion category, while their visual evoked potential was simultaneously recorded.ResultsThe two groups did not differ significantly in age, BMI, and years of education, but showed significant differences in their slow wave sleep ratio (P = 0.039), ESS (P = 0.006), MMSE (P < 0.001), and MOCA scores (P = 0.043). No significant difference was found in accuracy and response time on emotional face recognition between the two groups. N170 latency in the depressive group was significantly longer than the non-depressive group (P = 0.014 and 0.007) at the bilateral parieto-occipital lobe, while no significant difference in N170 amplitude was found. No significant difference in P300 amplitude or latency between the two groups. Furthermore, N170 amplitude at PO7 was positively correlated with the arousal index and negatively with MOCA scores (both P < 0.01).ConclusionOSAHS patients with depressive mood exhibit increased N170 latency and impaired facial emotion recognition ability. Special attention towards the depressive mood among OSAHS patients is warranted for its implications for patient care.

The influence of driver’s risk perception ability on driving decision-making: an ERP study

Driver’s risk perception ability is of great significance to traffic safety. Driver’s risk perception ability is reflected in the risk handling in traffic situation and has a great impact on driving decisions, especially speed decisions. However, the mechanism of the influence of risk perception on driving decisions under risk situations is still unclear. According to standardized risk perception test, we divided drivers into high risk perception ability (H-RPA) group and low risk perception ability (L-RPA) group. Participants were shown traffic pictures with different levels of risk and asked to make decisions about whether to slow down, while their electrical brain responses were recorded. All participants were interviewed after the experiment. The results showed that in the low-risk traffic situation, compared to the drivers with H-RPA, the drivers with L-RPA made less deceleration decisions and evoked larger N1 and smaller P1 amplitude. 93.75% of the drivers with L-RPA stated in interviews that they did not notice the traffic risks on the road. The results show that risk perception affects the allocation of attention to risks in traffic situations, leading to a decrease in the safety of driving decisions. Our research results provide a reference for the training of safe driving skills for drivers.

P1, N170, and N250 Event-related Potential Components Reflect Temporal Perception Processing in Face and Body Personal Identification.

Human faces and bodies represent various socially important signals. Although adults encounter numerous new people in daily life, they can recognize hundreds to thousands of different individuals. However, the neural mechanisms that differentiate one person from another person are unclear. This study aimed to clarify the temporal dynamics of the cognitive processes of face and body personal identification using face-sensitive ERP components (P1, N170, and N250). The present study performed three blocks (face-face, face-body, and body-body) of different ERP adaptation paradigms. Furthermore, in the above three blocks, ERP components were used to compare brain biomarkers under three conditions (same person, different person of the same sex, and different person of the opposite sex). The results showed that the P1 amplitude for the face-face block was significantly greater than that for the body-body block, that the N170 amplitude for a different person of the same sex condition was greater than that for the same person condition in the right hemisphere only, and that the N250 amplitude gradually increased as the degree of face and body sex-social categorization grew closer (i.e., same person condition > different person of the same sex condition > different person of the opposite sex condition). These results suggest that early processing of the face and body processes the face and body separately and that structural encoding and personal identification of the face and body process the face and body collaboratively.

Effects of chronic aerobic exercise on attentional bias among women with methamphetamine addiction

ObjectiveTo explore the effects of chronic exercise on attentional bias toward drug-related stimuli and on brain electrophysiological characteristics among women with methamphetamine addiction. MethodsIn total, 63 women with methamphetamine addiction were randomized to participate in a dance (n = 21; mean age, 32.16 ± 2.07 years), bicycle (n = 21; mean age, 32.59 ± 2.12 years), or control (maintained regular activities with little exercise; n = 21; mean age, 30.95 ± 2.81 years) group for 12 weeks. The participants in the three groups were not significantly different in terms of methamphetamine use or detoxification. Before and after the intervention, attentional bias was assessed using the dot-probe task, and event-related potentials were recorded during the task. ResultsThe mean attentional bias scores decreased significantly after the intervention in both exercise groups but not in the control group. After 12 weeks of dance exercise, the amplitudes of the N170, N2, P2, and P3 components of the event-related potentials decreased significantly during attentional bias processing. In addition, differences in N170 amplitudes for congruent vs. incongruent conditions in the dot-probe task were no longer observed. After 12 weeks of cycling exercise, N2 and P2 amplitudes decreased significantly. By contrast, there were no significant differences in N170, N2, P2, and P3 amplitudes in the control group before vs. after the intervention. ConclusionsChronic (12 weeks of) aerobic exercise reduced attentional bias toward drug-related cues by improving attentional inhibition and reducing the maintenance of extra attention to drug-related cues among women with methamphetamine addiction. Both dance and bicycle exercise improved the early recognition of drug-related cues, weakened the influence of the memory of previous drug use, and improved attentional bias behavior by strengthening attention control. Dance exercise, but not bicycling, also regulated emotional control and improved the attention selection process. These results provide theoretical and empirical evidence that chronic aerobic exercise may reduce the attentional bias toward drug-related cues to assist in the recovery of women with methamphetamine addiction.

Two sides of the same coin? How are neural mechanisms of cognitive control, attentional difficulties and creativity related?

Creativity has been associated with increased distractibility, but at the same time - and seemingly paradoxically- also with increased focused attention. Therefore, this study focused on the attentional processes involved in creativity and attentional difficulties. Healthy primary school children (N = 62) between 9 and 13 years old performed a selective attention paradigm while electrophysiological measures were recorded that measured the neural mechanisms of cognitive control (P300), conflict monitoring (N200), and subconscious attentional shifts (Mismatch Negativity). Attentional difficulties were measured with a parental questionnaire and creativity was measured with a divergent mathematical creativity task and a creative drawing task. We found that more creativity was related to decreased neural mechanisms of cognitive control and conflict monitoring (i.e. less negative N200 and smaller P300 amplitudes), however without affecting task performance. In addition, attentional difficulties were related to less negative N200 amplitudes on the attended and non-attended standard trials of the selective attention paradigm, as well as reduced task performance. Tentatively, the current findings suggest that original responses are associated with decreased cognitive control, possibly by promoting remote associations. Furthermore, our data shows that attentional difficulties are associated with a lack of selective attention and impaired information processing. Hence, although less cognitive control is often referred to in a negative way, it might facilitate certain aspects of creative thinking without affecting task performance.

Impact of Empathic Concern on Prosocial Behavior in Gain and Loss Contexts: Evidence from Event-Related Potential.

This study employs event-related potential (ERP) to examine the impact of empathic concern on prosocial decision-making with costs in both gain and loss contexts. In this experiment, participants can choose between two types of lottery tickets and pay lottery money to help the target person gain more money or lose less money. The behavioral results showed that regardless of the context of the decision (financial loss or gain), participants tended to help individuals who had induced high empathic concern. ERP results show that compared to the low-empathic-concern condition, the high-empathic-concern condition induced greater P3 amplitude in the gain context. However, this change in P3 amplitude caused by empathic concern did not occur in the context of loss. These findings indicate that empathic concern has different psychological mechanisms that moderate prosocial behavior in gain and loss contexts.

Brain stimulation over the left DLPFC enhances motivation for effortful rewards in patients with major depressive disorder

BackgroundAmotivation is a typical feature in major depressive disorder (MDD), which produces reduced willingness to exert effort. The dorsolateral prefrontal cortex (DLPFC) is a crucial structure in goal-directed actions and therefore is a potential target in modulating effortful motivation. However, it remains unclear whether the intervention is effective for patients with MDD. MethodsWe employed transcranial magnetic stimulation (TMS), computational modelling and event-related potentials (ERPs) to reveal the causal relationship between the left DLPFC and motivation for effortful rewards in MDD. Fifty patients underwent both active and sham TMS sessions, each followed by performing an Effort-Expenditure for Rewards Task, during which participants chose and implemented between low-effort/low-reward and high-effort/high-reward options. ResultsThe patients showed increased willingness to exert effort for rewards during the DLPFC facilitated session, compared with the sham session. They also had a trend in larger P3 amplitude for motivated attention toward chosen options, larger CNV during preparing for effort exertion, and larger SPN during anticipating a high reward. Besides, while behavior indexes for effortful choices were negatively related to depression severity in the sham session, this correlation was weakened in the active stimulation session. ConclusionsThese findings provide behavioral, computational, and neural evidence for the left DLPFC on effortful motivation for rewards. Facilitated DLPFC improves motor preparation and value anticipation after making decisions especially for highly effortful rewards in MDD. Facilitated DLPFC also has a potential function in enhancing motivated attention during cost-benefit trade-off. This neuromodulation effect provides a potential treatment for improving motivation in clinics.

Lack of habituation of visual-evoked potential in the interictal period is not a consistent neurophysiological marker of migraine: A cross-sectional analytical study

Objectives: Migraine is a frequent incapacitating neurovascular illness characterized by severe headache bouts. Individuals suffering from migraine appear to process auditory and visual information differently from those without migraine. The visual-evoked potential (VEP) is a commonly used standardized test to measure excitability in the occipital cortex. Patients with migraine exhibit amplification rather than habituation of stimulus-induced brain responses, between attacks. Our objective is to compare the amplitude of P100 and the latencies of N75, P100, and N145 (N and P represent negative and positive peaks, respectively, with average latency being subscripted with the alphabet) in the fourth block between migraine patients and controls and to determine the various clinical factors associated with the P100 mean amplitude and latency differences between the first and the fourth block in migraine patients. Materials and Methods: The study compared 20 migraine patients (with or without aura) and 20 apparently healthy subjects with no history of migraines or secondary headaches, focusing on the habituation of the VEP. Four blocks of 200 responses were recorded during the headache-free period, and the latencies and amplitudes of N75, P100, and N145 components were analyzed. Results: There was a statistically significant (P &lt; 0.05) decrement in the P100 amplitude in the fourth block when compared to the first block in both eyes in the controls as well as migraine patients. In addition, there was no statistically significant difference between controls and migraine sufferers in the P100 amplitude of the fourth block in either eye. The N145 latency in the fourth block was shorter in both eyes in migraine patients compared to controls (P &lt; 0.05). The mean P100 amplitude difference between the first and fourth block correlated negatively with age and positively with headache frequency, while there was a moderate negative correlation with headache duration. The mean P100 latency difference between the first and fourth block correlated positively with age and negatively with headache frequency, while there was a moderate positive correlation with headache duration. Conclusion: In our study, VEP habituation was not lacking in migraine patients which means that habituation of the P100 wave was noted in migraineurs. The VEP reveals neurological changes due to ischemia injury or neurotransmitter imbalances. Migraine alters cortical excitability, but it is unclear if these changes are due to altered excitatory connections, damaged inhibitory networks or subcortical pre-activation. Our findings suggest that at least during the interictal period, lack of habituation cannot be employed as a consistent neurophysiological marker of migraine across laboratories.

Comprehensive assessment of memory function, inhibitory control, neural activity, and cortisol levels in late pregnancy.

A considerable proportion of women subjectively perceive a detriment to their cognitive capacity during pregnancy, with decreased memory functions being the most frequently self-reported concerns. However, objective investigation of these perceived cognitive deficits has yielded inconsistent results. This study focused on memory functions during late pregnancy using multiple tasks designed to assess various memory indices, for example, working memory, learning rate, immediate recall, proactive and retroactive interference, delayed recall, retrieval efficiency, visuospatial constructional ability, recognition, and executive function. Additionally, sustained attention and inhibitory control were examined using a combined recognition stop-signal task. Electrophysiological brain activity during this task was recorded using a 128-channel electroencephalographic-event-related potential system. Salivary cortisol levels were assessed both prior to and following the experimental session. In contrast to the widely held belief, results demonstrated that women in late pregnancy did not exhibit a decline in their performance across the various memory tests. In terms of accuracy, there was not a single task in which poorer performance was found for pregnant women. The quality of memory performance was comparable, and in some cases even superior, among women in the pregnancy group. On the stop-signal task, pregnant women exhibited significantly better performance, and their electrophysiological data revealed greater centrally distributed P300 amplitude to "stop" signs, which may signify an enhanced neural efficiency in the domains of inhibitory executive control. Endocrine results revealed that pregnant women exhibited significantly lower levels of salivary cortisol, suggesting an attenuation of hypothalamic-pituitary-adrenocortical axis activity, which may contribute to the optimization of fetal development and growth.

Research on the cognitive neural mechanism of privacy empowerment illusion cues regarding comprehensibility and interpretability for privacy disclosures

In the era of artificial intelligence, privacy empowerment illusion has become a crucial means for digital enterprises and platforms to “manipulate” users and create an illusion of control. This topic has also become an urgent and pressing concern for current research. However, the existing studies are limited in terms of their perspectives and methodologies, making it challenging to fully explain why users express concerns about privacy empowerment illusion but repeatedly disclose their personal information. This study combines the associative-propositional evaluation model (APE) and cognitive load theory, using event-related potential (ERP) technology to investigate the underlying mechanisms of how the comprehensibility and interpretability of privacy empowerment illusion cues affect users’ immediate attitudes and privacy disclosure behaviours; these mechanisms are mediated by psychological processing and cognitive load differences. Behavioural research results indicate that in the context of privacy empowerment illusion cues with low comprehensibility, users are more inclined to disclose their private information when faced with high interpretability than they are when faced with low interpretability. EEG results show that in the context of privacy empowerment illusion cues with low comprehensibility, high interpretability induces greater P2 amplitudes than does low interpretability; low interpretability induces greater N2 amplitudes than does high interpretability. This study extends the scopes of the APE model and cognitive load theory in the field of privacy research, providing new insights into privacy attitudes. Doing so offers a valuable framework through which digital enterprises can gain a deeper understanding of users’ genuine privacy attitudes and immediate reactions under privacy empowerment illusion situations. This understanding can help increase user privacy protection and improve their overall online experience, making it highly relevant and beneficial.

The Relationship between Speech Sound Disorder and Cortical Auditory Evoked Potential

Plain Language SummarySpeech sound disorders (SSDs) are a language disorder prevalent in children and are featured by difficulties in the perception, production, and organization of speech sounds. This disorder can be associated with some deficits in the sound process. Thus, this study used a speech stimulus to measure the relationship between age and SSD severity, measured by the percentage of correct consonants, with cortical auditory evoked potentials (CAEPs). The latency of P1, N1, P2, N2, and P3 components and P1-N1, P2-N2, and P3 amplitudes were analyzed in both ears. No interference of severity, age, and ear was found in the latency of P1 and N1 components. The P2 latency was longer than the one proposed in the literature, and younger children with more severe SSD had lower mean latency values for this component. No interaction was found between the N2 latency and SSD severity. As for P3 latency, all children in this study had values within the normal limits for the age group. No SSD severity, age, and ear interference were observed in the P1-N1 amplitude. However, it was observed that the amplitude of this complex increases with age and decreases with SSD severity in the right ear. Finally, there was no SSD severity, age, and ear interference in P2-N2 and P3 amplitudes. CAEP analysis showed important aspects of the auditory path of children with SSD, suggesting difficulty in directing attention and discriminating the stimuli used, which can interfere with the phonological representation of speech sounds.

Role of Visual Evoked Potential in Direct Traumatic Optic Neuropathy: A Case Report

Traumatic optic neuropathy (TON) is a rare cause of visual impairment following blunt or sharp trauma and the diagnosis is established clinically. Lesions on the optic nerve may not always be visible in neuroimaging examinations. Studies on Visual Evoked Potential (VEP) in TON patients are still limited, despite being beneficial for objectively detecting optic nerve lesions. A 16-year-old male patient was referred to the neurology clinic with a sudden loss of vision in the left eye approximately 25 days after a head injury due to a motor vehicle accident. The patient had epidural bleeding and fractures in the orbital and facial bones, as revealed by a head CT scan. Neurological examination showed a visual acuity of 1/300 in the left eye, left midriasis, and a negative light reflex in the left eye. VEP examination of the left eye revealed prolonged P100 latency and a decrease in P100 amplitude (&gt;50%), indicating a lesion in the left optic nerve. This visual impairment persisted for up to 6 months post-head trauma. TON is a vision-threatening disorder that should be considered in patients with ocular or head trauma and visual impairment. A decrease in amplitude ratio &lt;50% and prolonged P100 latency &gt;140 ms are associated with poor visual function recovery. VEP examination is an objective assessment of visual pathway integrity and serves as one modality for early TON diagnosis and a predictor of visual function prognosis in TON patients. Keywords: diagnostic; prognostic; traumatic optic neuropathy; visual evoked potential