The impact of social hierarchies on neural response to feedback evaluations after advice giving.

Advisors generally evaluate advisee-relevant feedback after advice giving. The response to these feedback-(1) whether the advice is accepted and (2) whether the advice is optimal-usually involves prestige. Prior literature has found that prestige is the basis by which individuals attain a superior status in the social hierarchy. However, whether advisors are motivated to attain a superior status when engaging in advice giving remains uncharacterized. Using event-related potentials, this study investigates how advisors evaluate feedback after giving advice to superior (vs. inferior) status advisees. A social hierarchy was first established based on two advisees (one was ranked as superior status and another as inferior status) as well as participants' performance in a dot-estimation task in which all participants were ranked as medium status. Participants then engaged in a game in which they were assigned roles as advisors to a superior or inferior status advisee. Afterward, the participants received feedback in two phases. In Phase 1, participants were told whether the advisees accepted the advice provided. In Phase 2, the participants were informed whether the advice they provided was correct. In these two phases, when the advisee was of superior status, participants exhibited stronger feedback-related negativity and P300 difference in response to (1) whether their advice was accepted, and (2) whether their advice was correct. Moreover, the P300 was notably larger when the participants' correct advice led to a gain for a superior-status advisee. In the context of advice giving, advisors are particularly motivated to attain a superior status when the feedback involving social hierarchies, which is reflected in higher sensitivity to feedback associated with superior status advisees at earlier and later stages during feedback evaluations in brains.

Auditory learning of recurrent tone sequences is present in the newborn's brain.

The seemingly effortless ability of our auditory system to rapidly detect new events in a dynamic environment is crucial for survival. Whether the underlying brain processes are innate is unknown. To answer this question, electroencephalography was recorded while regularly patterned (REG) versus random (RAND) tone sequences were presented to sleeping neonates. Regular relative to random sequences elicited differential neural responses after only a single repetition of the pattern indicating the existence of an innate capacity of the auditory system to detect auditory sequential regularities. We show that the newborn auditory system accumulates evidence only somewhat longer than the minimum amount determined by the ideal Bayesian observer model (the prediction from a variable-order Markov chain model) before detecting a repeating pattern. Thus, newborns can quickly form representations for regular features of the sound input, preparing the way for learning the contingencies of the environment.

The influence of social pain experience on empathic neural responses: the moderating role of gender.

Empathy for pain, the ability to share and understand the pain of others, plays an important role in the survival and development of individuals. Previous studies have found that social pain experience affects empathy for pain, but potential gender differences have not been considered. The stage of information processing during which gender is most likely to play a moderating role has yet to be clarified. In the current study, we set up two groups (social pain experience priming: social exclusion group; positive social interaction experience priming: social inclusion group) with a Cyberball game paradigm. We recorded the electrophysiological responses when participants were completing an empathy task. An early frontal P2 and N2 differentiation between painful stimuli and neutral stimuli was observed and females showed larger P2 amplitudes than males. At the P3 stage, in the social exclusion group, males showed similar parietal P3 amplitudes for painful and neutral stimuli, while females showed smaller P3 amplitudes for painful stimuli. At the central-parietal late positive potential (LPP) stage, females in the social inclusion group showed larger LPP amplitudes for painful stimuli than males. Our results suggest that gender plays a significant moderating role in how social pain experience affects empathy for pain during the late cognitive processing stage. Experiment 2 was designed to investigate the cognitive mechanism behind the results for the P3 component in females and the results partially confirmed our speculation. This study provides a neurophysiological basis for the dynamic gender differences in the effects of social pain experience on empathy for pain.

Visual Selective Attention P300 Source in Frontal-Parietal Lobe: ERP and fMRI Study.

Visual selective attention can be achieved into bottom-up and top-down attention. Different selective attention tasks involve different attention control ways. The pop-out task requires more bottom-up attention, whereas the search task involves more top-down attention. P300, which is the positive potential generated by the brain in the latency of 300 ~ 600 ms after stimulus, reflects the processing of attention. There is no consensus on the P300 source. The aim of present study is to study the source of P300 elicited by different visual selective attention. We collected thirteen participants' P300 elicited by pop-out and search tasks with event-related potentials (ERP). We collected twenty-six participants' activation brain regions in pop-out and search tasks with functional magnetic resonance imaging (fMRI). And we analyzed the sources of P300 using the ERP and fMRI integration with high temporal resolution and high spatial resolution. ERP results indicated that the pop-out task induced larger P300 than the search task. P300 induced by the two tasks distributed at frontal and parietal lobes, with P300 induced by the pop-out task mainly at the parietal lobe and that induced by the search task mainly at the frontal lobe. Further ERP and fMRI integration analysis showed that neural difference sources of P300 were the right precentral gyrus, left superior frontal gyrus (medial orbital), left middle temporal gyrus, left rolandic operculum, right postcentral gyrus, and left angular gyrus. Our study suggests that the frontal and parietal lobes contribute to the P300 component of visual selective attention.

Neurophysiological correlates of abnormal auditory processing in episodic migraine during the interictal period.

BACKGROUND: The characteristics of the hypersensitivity to auditory stimuli during the interictal period in episodic migraine are discussed. The combined use of event-related potentials, time-frequency power and phase-synchronization can provide relevant information about the time-course of sensory-attentional processing in migraine and its underlying mechanisms. OBJECTIVE: The aim of this nested case-control study was to examine these processes in young, female, episodic migraine patients interictally and compare them to controls using an active auditory oddball task. METHOD: We recorded, using 20 channels, the electrophysiological brain activity of 21 women with episodic migraine without aura and 21 healthy matched controls without family history of migraine, during a novelty oddball paradigm. We collected sociodemographic and clinical data as well as scores related to disability, quality of life, anxiety and depression. We calculated behavioural measures including reaction times, hit rates and false alarms. Spectral power and phase-synchronization of oscillatory activity as well as event-related potentials were obtained for standard stimuli. For target and novel stimuli, event-related potentials were acquired. RESULTS: There were no significant differences at the behavioural level. In migraine patients, we found an increased phase-synchronization at the theta frequency range and a higher N1 response to standard trials. No differences were observed in spectral power. No evidence for a lack of habituation in any of the measures was seen between migraine patients and controls. The Reorienting Negativity was reduced in migraine patients as compared to controls on novel but not on target trials. CONCLUSION: Our findings suggest that migraine patients process stimuli as more salient, seem to allocate more of their attentional resources to their surrounding environment, and have less available resources to reorient attention back to the main task.

Do categorical representations modulate early perceptual or later cognitive visual processing? An ERP study.

Encoding of perceptual categorical information has been observed in later cognitive processing like memory encoding and maintenance, starting around 300 ms after stimulus onset (P300). However, it remains open whether categorical information is also encoded in early perceptual processing steps (reflected in the mismatch negativity component; vMMN). The main goal of this study was to assess the influence of categorical information on both early perceptual (i.e., vMMN component) and later cognitive (i.e., P300 component) processing within one paradigm. Hence, we combined an oddball paradigm with a delayed memory task. We used five-dot patterns belonging to different categories even though categorical information is not mirrored in their physical characteristics. Distinct vMMNs were observed for patterns belonging to the same as compared to different categories, suggesting that abstract categorical information was encoded during early perceptual processing. However, inconsistent with prior studies, we observed no effect of categories on the P300, indicating no additional encoding of categorical information in later cognitive stages of processing. Our findings emphasize that the encoding of categorical information depends on specific task demands and hence is more flexible and dynamic than previously suggested.

Custom-Fitted In- and Around-the-Ear Sensors for Unobtrusive and On-the-Go EEG Acquisitions: Development and Validation.

OBJECTIVES: This paper aims to validate the performance and physical design of a wearable, unobtrusive ear-centered electroencephalography (EEG) device, dubbed "EARtrodes", using early and late auditory evoked responses. Results would also offer a proof-of-concept for the device to be used as a concealed brain-computer interface (BCI). DESIGN: The device is composed of a custom-fitted earpiece and an ergonomic behind-the-ear piece with embedded electrodes made of a soft and flexible combination of silicone rubber and carbon fibers. The location of the conductive silicone electrodes inside the ear canal and the optimal geometry of the behind-the-ear piece were obtained through morphological and geometrical analysis of the human ear canal and the region around-the-ear. An entirely conductive generic earpiece was also developed to assess the potential of a universal, more affordable solution. RESULTS: Early latency results illustrate the conductive silicone electrodes' capability to record quality EEG signals, comparable to those obtained with traditional gold-plated electrodes. Additionally, late latency results demonstrate EARtrodes' capacity to reliably detect decision-making processes from the ear. CONCLUSIONS: EEG results validate the performance of EARtrodes as a circum-aural and intra-aural EEG recording system adapted for a wide range of applications in audiology, neuroscience, clinical research, and as an unobtrusive BCI.

Face Perception and Narcissism: Variations of Event-Related Potential Components (P1 & N170) with Admiration and Rivalry.

Previous studies have demonstrated that highly narcissistic individuals perceive themselves as grandiose and devaluate and sometimes overvalue others. These results are mainly based on behavioural data, but we still know little about the neural correlates underlying, such as perceptional processes. To this end, we investigated event-related potential components (ERP) of visual face processing (P1 and N170) and their variations with narcissism. Participants (N = 59) completed the Narcissistic Admiration and Rivalry Questionnaire and were shown pictures of their own face, a celebrity's face, and a stranger's face. Variations of P1 and N170 with Admiration and Rivalry were analysed using multilevel models. Results revealed moderating effects of both narcissism dimensions on the ERP components of interest. Participants with either high Admiration or low Rivalry scores showed a lower P1 amplitude when viewing their own face compared with when viewing a celebrity's face. Moreover, the Self-Stranger difference in the N170 component (higher N170 amplitude in the Self condition) was larger for higher Rivalry scores. The findings showed, for the first time, variations of both narcissism dimensions with ERPs of early face processing. We related these effects to processes of attentional selection, an expectancy-driven perception, and the mobilisation of defensive systems. The results demonstrated that by linking self-report instruments to P1 and N170, and possibly to other ERP components, we might better understand self- and other-perception in narcissism.

Neural and behavioral measures suggest that cognitive and affective functioning interactions mediate risk for psychosis-proneness symptoms in youth with chromosome 22q11.2 deletion syndrome.

Behavioral components of chromosome 22q11.2 deletion syndrome (22q), caused by the most common human microdeletion, include cognitive and adaptive functioning impairments, heightened anxiety, and an elevated risk of schizophrenia. We investigated how interactions between executive function and the largely overlooked factor of emotion regulation might relate to the incidence of symptoms of psychotic thinking in youth with 22q. We measured neural activity with event-related potentials (ERPs) in variants of an inhibitory function (Go/No-Go) experimental paradigm that presented affective or non-affective stimuli. The study replicated inhibition impairments in the 22q group that were amplified in the presence of stimuli with negative, more than positive affective salience. Importantly, the anterior N2 conflict monitoring ERP significantly increased when youth with 22q viewed angry and happy facial expressions, unlike the typically developing participants. This suggests that youth with 22q may require greater conflict monitoring resources when controlling their behavior in response to highly salient social signals. This evidence of both behavioral and neurophysiological differences in affectively influenced inhibitory function suggests that frequently anxious youth with 22q may struggle more with cognitive control in emotionally charged social settings, which could influence their risk of developing symptoms of psychosis.

Sex differences in vocalization are reflected by event-related potential components in the music frog.

Sex differences in vocalization have been commonly found in vocal animals. It remains unclear, however, how animals perceive and discriminate these differences. The amplitudes and latencies of event-related potentials (ERP) components can reflect the auditory processing efficiency and time course. We investigated the neural mechanisms of auditory processing in the Emei music frog (Nidirana daunchina) using an Oddball paradigm with ERP. We recorded and analyzed eletroencephalogram (EEG) signals from the forebrain and midbrain when the subjects listened to white noise (WN) and conspecific sex-specific vocalizations. We found that (1) both amplitudes and latencies of some ERP components evoked by conspecific calls were significantly higher than those by WN, suggesting the music frogs can discriminate conspecific vocalizations from background noise; (2) both amplitudes and latencies of most ERP components evoked by female calls were significantly higher or longer than those by male calls, implying that the ERP components can reflect sex differences in vocalization; and (3) there were significant differences in ERP amplitudes between male and female subjects, suggesting a sexual dimorphism in auditory perception. Together, the present results indicate that the music frog could discriminate conspecific calls from noise, male's calls from female's ones, and sexual dimorphism of auditory perception existed in this species.

Face Selective Neural Activity: Comparisons Between Fixed and Free Viewing.

Event Related Potentials (ERPs) are widely used to study category-selective EEG responses to visual stimuli, such as the face-selective N170 component. Typically, this is done by flashing stimuli at the point of static gaze fixation. While allowing for good experimental control, these paradigms ignore the dynamic role of eye-movements in natural vision. Fixation-related potentials (FRPs), obtained using simultaneous EEG and eye-tracking, overcome this limitation. Various studies have used FRPs to study processes such as lexical processing, target detection and attention allocation. The goal of this study was to carefully compare face-sensitive activity time-locked to an abrupt stimulus onset at fixation, with that time-locked to a self-generated fixation on a stimulus. Twelve participants participated in three experimental conditions: Free-viewing (FRPs), Cued-viewing (FRPs) and Control (ERPs). We used a multiple regression approach to disentangle overlapping activity components. Our results show that the N170 face-effect is evident for the first fixation on a stimulus, whether it follows a self-generated saccade or stimulus appearance at fixation point. The N170 face-effect has similar topography across viewing conditions, but there were major differences within each stimulus category. We ascribe these differences to an overlap of the fixation-related lambda response and the N170. We tested the plausibility of this account using dipole simulations. Finally, the N170 exhibits category-specific adaptation in free viewing. This study establishes the comparability of the free-viewing N170 face-effect with the classic event-related effect, while highlighting the importance of accounting for eye-movement related effects.

Maternal antenatal anxiety and electrophysiological functioning amongst a sub-set of preschoolers participating in the GUSTO cohort.

BACKGROUND: Antenatal maternal anxiety is a risk for offspring psychological and cognitive difficulties. The preschool years represent an important time for brain development, and so may be a window for intervention. However, electrophysiological investigations of maternal anxiety and preschoolers' brain functioning are lacking. We ask whether anxiety symptoms predict neurophysiology, and consider timing specificity (26-weeks antenatal or 24-months postnatal), form of insult (anxiety symptoms, per se, or also depression symptoms), and offspring gender. METHODS: The sample consisted of a subset of 71 mothers and their 3 year old children taking part in the prospective birth cohort, GUSTO. Mothers provided antenatal (26 weeks) and postnatal (2 years) anxiety and depressive symptomatology data, respectively via the "State Trait Anxiety Questionnaire" and the "Edinburgh Postpartum Depression Scale." Offspring provided electrophysiological data, obtained while they indicated the emotional expression of actors whose facial expressions remained consistent throughout a pre-switch block, but were reversed at "post-switch." RESULTS: Three electrophysiological components linked to different information processing stages were identified. The two earliest occurring components (i.e., the N1 and P2) differed across blocks. During post-switch, both were significantly predicted by maternal anxiety, after controlling for pre-switch neurophysiology. Similar results were observed with depression. Antenatal mental health remained a significant predictor after controlling for postnatal mental health. CONCLUSION: In combination with past work, these findings suggest the importance of reducing symptoms in women prior to and during pregnancy, and offering support to offspring early in development.

Early enhanced processing and delayed habituation to deviance sounds in autism spectrum disorder.

Children with autism spectrum disorder (ASD) exhibit difficulties processing and encoding sensory information in daily life. Cognitive response to environmental change in control individuals is naturally dynamic, meaning it habituates or reduces over time as one becomes accustomed to the deviance. The origin of atypical response to deviance in ASD may relate to differences in this dynamic habituation. The current study of 133 children and young adults with and without ASD examined classic electrophysiological responses (MMN and P3a), as well as temporal patterns of habituation (i.e., N1 and P3a change over time) in response to a passive auditory oddball task. Individuals with ASD showed an overall heightened sensitivity to change as exhibited by greater P3a amplitude to novel sounds. Moreover, youth with ASD showed dynamic ERP differences, including slower attenuation of the N1 response to infrequent tones and the P3a response to novel sounds. Dynamic ERP responses were related to parent ratings of auditory sensory-seeking behaviors, but not general cognition. As the first large-scale study to characterize temporal dynamics of auditory ERPs in ASD, our results provide compelling evidence that heightened response to auditory deviance in ASD is largely driven by early sensitivity and prolonged processing of auditory deviance.

Recommendations for Developing an EEG Laboratory at a Primarily Undergraduate Institution.

Given its relatively low cost and minimal required space, an EEG laboratory provides the most feasible human cognitive neuroscience technique to implement at primarily undergraduate institutions (PUI). However, neuroscience programs at PUIs may be deterred from incorporating EEG methods into their research programs and/or classrooms due to limited funds and resources. This article provides recommended guidelines for faculty researchers looking to set up an EEG lab at their host PUIs with an emphasis on feasibility. We offer considerations regarding infrastructure, equipment, personnel, and potential sources of funding. A case study is also provided, describing the successful implementation and development of an EEG/ERP lab at a Midwest PUI, Baldwin Wallace University. Our goal is to offer diverse options for starting a new, or revitalizing an existing, EEG lab. We contend that such a laboratory at a PUI will advance undergraduate students' access to interdisciplinary neuroscience research and curricular opportunities.

Abnormalities in early visual processes are linked to hypersociability and atypical evaluation of facial trustworthiness: An ERP study with Williams syndrome.

Accurate assessment of trustworthiness is fundamental to successful and adaptive social behavior. Initially, people assess trustworthiness from facial appearance alone. These assessments then inform critical approach or avoid decisions. Individuals with Williams syndrome (WS) exhibit a heightened social drive, especially toward strangers. This study investigated the temporal dynamics of facial trustworthiness evaluation in neurotypic adults (TD) and individuals with WS. We examined whether differences in neural activity during trustworthiness evaluation may explain increased approach motivation in WS compared to TD individuals. Event-related potentials were recorded while participants appraised faces previously rated as trustworthy or untrustworthy. TD participants showed increased sensitivity to untrustworthy faces within the first 65-90 ms, indexed by the negative-going rise of the P1 onset (oP1). The amplitude of the oP1 difference to untrustworthy minus trustworthy faces was correlated with lower approachability scores. In contrast, participants with WS showed increased N170 amplitudes to trustworthy faces. The N170 difference to low-high-trust faces was correlated with low approachability in TD and high approachability in WS. The findings suggest that hypersociability associated with WS may arise from abnormalities in the timing and organization of early visual brain activity during trustworthiness evaluation. More generally, the study provides support for the hypothesis that impairments in low-level perceptual processes can have a cascading effect on social cognition.

Effects of language experience and stimulus context on the neural organization and categorical perception of speech.

Categorical perception (CP) represents a fundamental process in converting continuous speech acoustics into invariant percepts. Using scalp-recorded event-related brain potentials (ERPs), we investigated how tone-language experience and stimulus context influence the CP for lexical tones-pitch patterns used by a majority of the world's languages to signal word meaning. Stimuli were vowel pairs overlaid with a high-level tone (T1) followed by a pitch continuum spanning between dipping (T3) and rising (T2) contours of the Mandarin tonal space. To vary context, T1 either preceded or followed the critical T2/T3 continuum. Behaviorally, native Chinese showed stronger CP as evident by their steeper, more dichotomous psychometric functions and faster identification of linguistic pitch patterns than native English-speaking controls. Stimulus context produced shifts in both groups' categorical boundary but was more exaggerated in native listeners. Analysis of source activity extracted from primary auditory cortex revealed overall stronger neural encoding of tone in Chinese compared to English, indicating experience-dependent plasticity in cortical pitch processing. More critically, "neurometric" functions derived from multidimensional scaling and clustering of source ERPs established: (i) early auditory cortical activity could accurately predict listeners' psychometric speech identification and contextual shifts in the perceptual boundary; (ii) neurometric profiles were organized more categorically in native speakers. Our data show that tone-language experience refines early auditory cortical brain representations so as to supply more faithful templates to neural mechanisms subserving lexical pitch categorization. We infer that contextual influence on the CP for tones is determined by language experience and the frequency of pitch patterns as they occur in listeners' native lexicon.

Implicit processing of heroin and emotional cues in abstinent heroin users: early and late event-related potential effects.

BACKGROUND: The abnormal cognitive processing of drug cues is a core characteristic of drug dependence. Previous research has suggested that the late positive potential (LPP) of heroin users is increased by heroin-related stimuli because of the attention-grabbing nature of such stimuli. OBJECTIVES: The present research used a modified emotional Stroop (eStroop) task to examine whether there was an early posterior negativity (EPN) modulation to heroin cues compared with emotional or neutral stimuli in heroin dependent subjects. METHODS: Fifteen former heroin users and 15 matched controls performed the eStroop task, which was composed of positive, negative, heroin-related, and neutral pictures with superimposed color squares. Participants responded to the color of the square and not to the picture while behavioral data and event-related potentials were recorded. RESULTS: There were no significant differences of EPN amplitudes to emotional and neutral stimuli between heroin users and controls. However, heroin users displayed increased EPN modulation for heroin cues, whereas this modulation was absent in controls. CONCLUSIONS: Drug-related cues acquire motivational salience and automatically capture the attention of heroin users at early processing stages, even when engaged in a non-drug-related task. The EPN to heroin cues could represent a novel electrophysiological index with clinical implications for selecting abstinent drug users who are at increased risk of relapse or to evaluate treatment interventions.

EEG signatures of arm isometric exertions in preparation, planning and execution.

The electroencephalographic (EEG) activity patterns in humans during motor behaviour provide insight into normal motor control processes and for diagnostic and rehabilitation applications. While the patterns preceding brisk voluntary movements, and especially movement execution, are well described, there are few EEG studies that address the cortical activation patterns seen in isometric exertions and their planning. In this paper, we report on time and time-frequency EEG signatures in experiments in normal subjects (n=8), using multichannel EEG during motor preparation, planning and execution of directional centre-out arm isometric exertions performed at the wrist in the horizontal plane, in response to instruction-delay visual cues. Our observations suggest that isometric force exertions are accompanied by transient and sustained event-related potentials (ERP) and event-related (de-)synchronisations (ERD/ERS), comparable to those of a movement task. Furthermore, the ERPs and ERD/ERS are also observed during preparation and planning of the isometric task. Comparison of ear-lobe-referenced and surface Laplacian ERPs indicates the contribution of superficial sources in supplementary and pre-motor (FC(z)), parietal (CP(z)) and primary motor cortical areas (C1 and FC1) to ERPs (primarily negative peaks in frontal and positive peaks in parietal areas), but contribution of deep sources to sustained time-domain potentials (negativity in planning and positivity in execution). Transient and sustained ERD patterns in µ and ß frequency bands of ear-lobe-referenced and surface Laplacian EEG indicate the contribution of both superficial and deep sources to ERD/ERS. As no physical displacement happens during the task, we can infer that the underlying mechanisms of motor-related ERPs and ERD/ERS patterns do not only depend on change in limb coordinate or muscle-length-dependent ascending sensory information and are primary generated by motor preparation, direction-dependent planning and execution of isometric motor tasks. The results contribute to our understanding of the functions of different brain regions during voluntary motor tasks and their activity signatures in EEG can shed light on the relationships between large-scale recordings such as EEG and other recordings such as single unit activity and fMRI in this context.

Conceptual priming for realistic auditory scenes and for auditory words.

Two experiments were conducted using both behavioral and Event-Related brain Potentials methods to examine conceptual priming effects for realistic auditory scenes and for auditory words. Prime and target sounds were presented in four stimulus combinations: Sound-Sound, Word-Sound, Sound-Word and Word-Word. Within each combination, targets were conceptually related to the prime, unrelated or ambiguous. In Experiment 1, participants were asked to judge whether the primes and targets fit together (explicit task) and in Experiment 2 they had to decide whether the target was typical or ambiguous (implicit task). In both experiments and in the four stimulus combinations, reaction times and/or error rates were longer/higher and the N400 component was larger to ambiguous targets than to conceptually related targets, thereby pointing to a common conceptual system for processing auditory scenes and linguistic stimuli in both explicit and implicit tasks. However, fine-grained analyses also revealed some differences between experiments and conditions in scalp topography and duration of the priming effects possibly reflecting differences in the integration of perceptual and cognitive attributes of linguistic and nonlinguistic sounds. These results have clear implications for the building-up of virtual environments that need to convey meaning without words.

Relationship Between the Parietal Cortex and Task Switching: Transcranial Direct Current Stimulation Combined with an Event-related Potential Study.

Task switching refers to a set of cognitive processes involved in shifting attention from one task to another. In recent years, researchers have applied transcranial direct current stimulation (tDCS) to investigate the causal relationship between the parietal cortex and task switching. However, results from available studies are highly inconsistent. This may be due to the unclear understanding of the underlying mechanisms. Therefore, the current study utilized event-related potential (ERP) analysis to investigate the modulatory effects of tDCS on task-switching processes. Twenty-four subjects were recruited to perform both predictable and unpredictable parity/magnitude tasks under anodal (RA) and sham conditions. The results showed no significant changes in behavioral performance. However, marked tDCS-induced ERP changes were observed. Specifically, for the predictable task switching, compared with the sham condition, the target-N2 component occurred significantly earlier for switch trials than repeat trials under the RA condition in males, while no difference was found in females. For unpredictable task switching, under the sham condition, the P2 peak was significantly larger for switch trials compared with repeat trials, whereas this difference was not observed under the RA condition. These results indicated the causal relationship between the right parietal cortex and exogenous adjustment processes involved in task switching. Moreover, anodal tDCS over the right parietal cortex may lead to the manifestation of gender differences.