Contingent Negative Variation Amplitude Research Articles

Connection of social anxiety to impaired pattern of cognitive control and underlying motivational deficiencies: Evidence from event-related potentials.

Numerous studies have established a correlation between social anxiety and poor cognitive control. However, little is known about the cognitive control pattern of individuals with high social anxiety (HSAs) and the underlying mechanisms. Based on the Dual Mechanisms of Control framework and the Expected Value of Control theory, this study explored whether HSAs have an impaired cognitive control pattern (Experiment 1) and whether motivational deficiencies underlie the impaired control pattern (Experiment 2). In Experiment 1, 21 individuals with low social anxiety (LSAs) and 21 HSAs completed an AX-Continuous Performance Task. Results showed that HSAs had a smaller P3b amplitude than LSAs, indicating their weakened proactive control in the cue processing stage, but a larger contingent negative variation (CNV) on cue B as compensation for the negative effects of anxiety in the response preparation stage. No group difference was found in N2 and P3a amplitude on probes, suggesting that reactive control in HSAs was not affected compared to LSAs. In Experiment 2, 21 LSAs and 21 HSAs completed a cued-flanker task, where the likelihood of proactive control engagement was manipulated. The results revealed that HSAs exhibited motivation deficiencies in engaging in proactive control, as evidenced by P3b, CNV amplitude, and response times. These findings shed light on the impaired cognitive control pattern of HSAs and suggest that motivational deficiencies may be the crucial underlying factor.

Early and late contingent negative variation (CNV) reflect different aspects of deficits in schizophrenia.

Abnormal reward processing and psychomotor slowing are well-known in schizophrenia (SZ). As a slow frontocentral potential, contingent negative variation (CNV) is associated with anticipatory attention, motivation and motor planning. The present study aims to evaluate the early and late amplitude and latencies of CNV in patients with SZ compared to healthy controls during a reward processing task and to show its association with clinical symptoms. We recruited 21 patients with SZ and 22 healthy controls to compare early and late CNV amplitude and latency values during a Monetary Incentive Delay (MID) Task between groups. Patients' symptom severity, levels of negative symptoms and depressive symptoms were assessed. Clinical features of the patients were further examined for their relation with CNV components. In conclusion, we found decreased early CNV amplitudes in SZ during the reward condition. They also displayed diminished and shortened late CNV responses for incentive cues, specifically at the central location. Furthermore, early CNV amplitudes exhibited a significant correlation with positive symptoms. Both CNV latencies were linked with medication dosage and the behavioural outcomes of the MID task. We revealed that early and late CNV exhibit different functions in neurophysiology and correspond to various facets of the deficits observed in patients. Our findings also emphasized that slow cortical potentials are indicative of deficient motivational processes as well as impaired reaction preparation in SZ. To gain a deeper understanding of the cognitive and motor impairments associated with psychosis, future studies must compare the effects of CNV in the early and late phases.

Contingent Negative Variation in the Evaluation of Neurocognitive Disorders Due to Possible Alzheimer's Disease.

The usefulness of Contingent Negative Variation (CNV) potential as a biomarker of neurocognitive disorders due to possible Alzheimer's disease, is based on its possible physiological correlates. However, its application in the diagnostic evaluation of these disorders is still incipient. The aim of this study is to characterize the patterns of cognitive processing of information in the domain of nonspecific global attention, by recording potential CNV in a group of patients with neurocognitive disorders due to possible Alzheimer's disease. An experimental study of cases and controls was carried out. The sample included 39 patients classified according to DSM-5 with a neurocognitive disorder subtype possibly due Alzheimer's disease, and a Control Group of 53 subjects with normal cognitive functions. CNV potential was registered using standard protocol. The analysis of variance obtained significant differences in mean values and confidence intervals of total CNV amplitude between the three study groups. The late CNV segment amplitudes makes it possible to discriminate between the level of mild and major dysfunction in the group of patients. The CNV total amplitudes of potential allows for effective discrimination between normal cognitive functioning and neurocognitive disorders due to possible Alzheimer's disease.

Contingent negative variation as an evaluation indicator of neurocognitive disorder after traumatic brain injury.

Neurocognitive disorders are commonly observed in patients suffering from traumatic brain injury (TBI). Methods to assess neurocognitive disorders have thus drawn the general attention of the public, especially electrophysiology parameter such as contingent negative variation (CNV), which has been given more emphasis as a neurophysiological marker in event-related potentials (ERPs) for diagnosing a neurocognitive disorder and assessing its severity. The present study focused on the correlations between CNV parameters and levels of daily living activities and social function to explore the potential of CNV as an objective assessment tool. Thirty-one patients with a diagnosis of neurocognitive disorder after a TBI according to ICD-10 were enrolled as the patient group, and 24 matched healthy volunteers were enrolled as the control group. The activity of daily living scale, functional activities questionnaire, social disability screening schedule, and scale of personality change following TBI were used to assess daily living activity and social function. The scale scores in patients were significantly higher than those in controls. Maximum amplitudes before S2 and during the post-imperative negative variation (PINV) period were also significantly higher in the patient group compared to the control group and were positively correlated with four scale scores. The duration of PINV at Fz and Cz was significantly shorter in the patient group than in the control group. The CNV return to baseline from a positive wave at electrode Fz and Cz occurred significantly earlier in the control group than in the patient group, while at Pz, the result showed the opposite. Lower amplitudes of CNV were associated with more severe neurocognitive disorder and greater impairments in daily life abilities and social function. The duration of PINV and the latency of returning to baseline from a positive wave were correlated with the neurocognitive disorder to some extent. CNV could be used as an objective, electrophysiology-based parameter for evaluating the severity of the neurocognitive disorder and personality changes after TBI.

Unveiling the Role of Contingent Negative Variation (CNV) in Migraine: A Review of Electrophysiological Studies in Adults and Children.

Migraine has been considered a chronic neuronal-based pain disorder characterized by the presence of cortical hyperexcitability. The Contingent Negative Variation (CNV) is the most explored electrophysiological index in migraine. However, the findings show inconsistencies regarding its functional significance. To address this, we conducted a review in both adults and children with migraine without aura to gain a deeper understanding of it and to derive clinical implications. The literature search was conducted in the PubMed, SCOPUS and PsycINFO databases until September 2022m and 34 articles were retrieved and considered relevant for further analysis. The main results in adults showed higher CNV amplitudes (with no habituation) in migraine patients. Electrophysiological abnormalities, particularly focused on the early CNV subcomponent (eCNV), were especially prominent a few days before the onset of a migraine attack, normalizing during and after the attack. We also explored various modulatory factors, including pharmacological treatments-CNV amplitude was lower after the intake of drugs targeting neural hyperexcitability-and other factors such as psychological, hormonal or genetic/familial influences on CNV. Although similar patterns were found in children, the evidence is particularly scarce and less consistent, likely due to the brain's maturation process during childhood. As the first review exploring the relationship between CNV and migraine, this study supports the role of the CNV as a potential neural marker for migraine pathophysiology and the prediction of pain attacks. The importance of further exploring the relationship between this neurophysiological index and childhood migraine is critical for identifying potential therapeutic targets for managing migraine symptoms during its development.

Encoding, working memory, or decision: how feedback modulates time perception.

The hypothesis that individuals can accurately represent temporal information within approximately 3 s is the premise of several theoretical models and empirical studies in the field of temporal processing. The significance of accurately representing time within 3 s and the universality of the overestimation contrast dramatically. To clarify whether this overestimation arises from an inability to accurately represent time or a response bias, we systematically examined whether feedback reduces overestimation at the 3 temporal processing stages of timing (encoding), working memory, and decisions proposed by the scalar timing model. Participants reproduced the time interval between 2 circles with or without feedback, while the electroencephalogram (EEG) was synchronously recorded. Behavioral results showed that feedback shortened reproduced times and significantly minimized overestimation. EEG results showed that feedback significantly decreased the amplitude of contingent negative variation (CNV) in the decision stage but did not modulate the CNV amplitude in the encoding stage or the P2-P3b amplitudes in the working memory stage. These results suggest that overestimation arises from response bias when individuals convert an accurate representation of time into behavior. Our study provides electrophysiological evidence to support the conception that short intervals under approximately 3 s can be accurately represented as "temporal gestalt."

Anticipatory reward dysfunction in alcohol dependence: An electroencephalography monetary incentive delay task study

A wealth of functional magnetic resonance imaging monetary incentive delay task (MIDT) research has shown alcohol dependency is associated with a hypoactive striatal response during gain anticipation (gain > neutral) and loss anticipation (loss > neutral). Electroencephalography (EEG) holds clinical advantages over fMRI (high temporal resolution, low cost, portable) however its use to study reward processing in alcohol dependence is limited. We aimed to carry out the first EEG MIDT (eMIDT) study in alcohol dependence. 21 abstinent alcohol dependent individuals and 26 controls performed an MIDT while neural activity was recorded using 64-channel EEG. Trial averaged event-related potentials (ERPs) and single-trial machine learning discriminant analyses were applied to EEG data. Clinical variables related to severity of dependence were collected and relationships with ERP data explored. Alcohol dependent individuals, compared with healthy controls, had blunted cue-P3 amplitudes for gain and loss anticipation (interaction: p = 0.019); and elevated contingent negative variation amplitudes for all conditions (gain, loss, neutral)(main effect: p < 0.001) which was associated with increased alcohol consumption (p = 0.002). The machine learning analyses demonstrated alcohol dependent individuals had reduced ability to discriminate between loss and neutral cues between 328 – 350 ms (p = 0.040), 354 – 367 ms (p = 0.047) and 525 – 572 ms (p = 0.022). The eMIDT approach is demonstrated to be a low-cost, sensitive measure of dysfunctional anticipatory reward processing in alcohol dependence, which we propose is ideal for big data approaches to prognostic psychiatry and translation into clinical practice.

The role of cerebellum in timing processing: A contingent negative variation study

Time management is an important aspect of human behaviour and cognition. Several brain regions are thought to be involved in motor timing and time estimation tasks. However, subcortical regions such as the basal nuclei and cerebellum seem to play a role in timing control.The aim of this study was to investigate the role of the cerebellum in temporal processing. For this purpose, we transitorily inhibited cerebellar activity by means of cathodal transcranial direct current stimulation (tDCS) and studied the effects of this inhibition on contingent negative variation (CNV) parameters elicited during a S1-S2 motor task in healthy subjects.Sixteen healthy subjects underwent a S1-S2 motor task prior to and after cathodal and sham cerebellar tDCS in separate sessions. The CNV task consisted of a duration discrimination task in which subjects had to determine whether the duration of a probe interval trial was shorter (800 ms), longer (1600 ms), or equal to the target interval of 1200 ms.A reduction in total CNV amplitude emerged only after cathodal tDCS for short and target interval trials, while no differences were detected for the long interval trial. Errors were significantly higher after cathodal tDCS than at baseline evaluation of short and target intervals. No reaction time differences were found for any time interval after the cathodal and sham sessions.These results point to a role of the cerebellum in time perception. In particular, the cerebellum seems to regulate temporal interval discrimination for second and sub-second ranges.

Medial prefrontal transcranial alternating current stimulation for apathy in Huntington's disease

We investigated the effects of transcranial alternating current stimulation (tACS) targeted to the bilateral medial prefrontal cortex (mPFC) and administered at either delta or alpha frequencies, on brain activity and apathy in people with Huntington's disease (HD) (n = 17). Given the novelty of the protocol, neurotypical controls (n = 20) were also recruited. All participants underwent three 20-min sessions of tACS; one session at alpha frequency (Individualised Alpha Frequency (IAF), or 10 Hz when an IAF was not detected); one session at delta frequency (2 Hz); and a session of sham tACS. Participants completed the Monetary Incentive Delay (MID) task with simultaneous recording of EEG immediately before and after each tACS condition. The MID task presents participants with cues signalling potential monetary gains or losses that increase activity in key regions of the cortico-basal ganglia-thalamocortical networks, with dysfunction of the latter network being implicated in the pathophysiology of apathy. We used the P300 and Contingent Negative Variation (CNV) event-related potentials elicited during the MID task as markers of mPFC engagement. HD participants' CNV amplitude significantly increased in response to alpha-tACS, but not delta-tACS or sham. Neurotypical controls' P300 and CNV were not modulated by any of the tACS conditions, but they did demonstrate a significant decrease in post-target response times following alpha-tACS. We present this as preliminary evidence of the ability of alpha-tACS to modulate brain activity associated with apathy in HD.

Contingent negative variation to tactile stimuli - differences in anticipatory and preparatory processes between participants with and without blindness.

People who are blind demonstrate remarkable abilities within the spared senses and compensatory enhancement of cognitive skills, underscored by substantial plastic reorganization in relevant neural areas. However, little is known about whether people with blindness form top-down models of the world on short timescales more efficiently to guide goal-oriented behavior. This electroencephalography study investigates this hypothesis at the neurophysiological level, focusing on contingent negative variation (CNV) as a marker of anticipatory and preparatory processes prior to expected events. In sum, 20 participants with blindness and 27 sighted participants completed a classic CNV task and a memory CNV task, both containing tactile stimuli to exploit the expertise of the former group. Although the reaction times in the classic CNV task did not differ between groups, participants who are blind reached higher performance rates in the memory task. This superior performance co-occurred with a distinct neurophysiological profile, relative to controls: greater late CNV amplitudes over central areas, suggesting enhanced stimulus expectancy and motor preparation prior to key events. Controls, in contrast, recruited more frontal sites, consistent with inefficient sensory-aligned control. We conclude that in more demanding cognitive contexts exploiting the spared senses, people with blindness efficiently generate task-relevant internal models to facilitate behavior.

Reward advantage over punishment for incentivizing visual working memory.

The prospects of gaining reward and avoiding punishment widely influence human behavior. Despite of numerous attempts to investigate the influence of motivational signals on working memory (WM), whether the valence and the magnitude of motivational signals interactively influence WM performance remains unclear. To investigate this, the present study used a free-recall working memory task with EEG recording to compare the effect of incentive valence (reward or punishment), as well as the magnitude of incentives on visual WM. Behavioral results revealed that the presence of incentive signals improved WM precision when compared with no-incentive condition, and compared with punishing cues, rewarding cues led to greater facilitation in WM precision, as well as confidence ratings afterward. Moreover, event related potential (ERP) results suggested that compared with punishment, reward led to an earlier latency of late positive component (LPC), a larger amplitude of contingent negative variation (CNV) during the expectation period, and a larger P300 amplitude during the sample and delay periods. Furthermore, reward advantage over punishment in behavioral and neural results were correlated, such that individuals with larger CNV difference between reward and punishment conditions also report greater distinction in confidence ratings between the two conditions. In sum, our results demonstrate what and how rewarding cues cause more beneficial effects than punishing cues when incentivizing visual WM.

Efficient use of peripheral information for temporal prediction

We adapt to the environment by predicting subsequent events. Generally, intervals between predictions and events make it difficult to predict the events accurately. Previous studies reported that using peripheral information is useful for maintaining predictions of subsequent events; however, it remains unclear how this information maintains the accuracy of the prediction. I presented peripheral visual stimuli in a discrimination task and manipulated the number of times these stimuli were presented while participants were waiting for a task-relevant visual stimulus, and compared participants’ response times and event-related brain potentials in Experiment 1. In addition, the influence of the difficulty of predicting the task-relevant visual stimulus was examined in Experiment 2. In both experiments, contingent negative variation (CNV) amplitude immediately before the task-relevant visual stimulus appeared was larger under the condition where many peripheral visual stimuli were presented, and the response time was shorter under this condition. In addition, the largest CNV amplitude under this condition was elicited by the third peripheral visual stimulus, followed in order by the first and second peripheral visual stimuli. These results show that we can predict the timing of events that occur with a delay after the prediction by using peripheral information. Moreover, this peripheral information is processed according to the importance of predicting a task-relevant stimulus, and attentional resources are allocated efficiently. These results provide evidence of the predictive function for temporal prediction of using peripheral information and the allocation of cognitive resources.

Impaired sustained attention in groups at high risk for antisocial personality disorder: A contingent negative variation and standardized low-resolution tomographic analysis study.

This study aimed to explore the characteristics of contingent negative variation (CNV) in groups at high risk for antisocial personality disorder. A classic CNV paradigm was used to compare the characteristics of attention maintenance among a group of individuals with conduct disorder (CD group; n = 27), a group of individuals with antisocial personality traits (AP; n = 29), a group of individuals with conduct disorder and antisocial personality traits (CD + AP group; n = 25), and a group of healthy controls (CG group; n = 30), to examine the characteristics of the amplitude and latency of CNV in different processing stages. Results of the event-related potential analysis were as follows: The mean amplitude analysis between 500 and 1,000 ms revealed that the mean CNV amplitudes in the CD + AP group (-1.388 ± 0.449 μV, P < 0.001) were significantly lower than that in the CG group (-4.937 ± 0.409 μV). The mean amplitude analysis between 1,000 and 1,500 ms revealed that the mean CNV amplitude in the CD + AP group (-0.931 ± 0.646 μV) was significantly lower than that in the CG group (4.809 ± 0.589 μV, P < 0.001). The mean amplitude analysis between 1,500 and 2,000 ms revealed that the mean CNV amplitude in the CG group (3.121 ± 0.725 μV) was significantly higher than that in the CD + AP group (-0.277 ± 0.795 μV, P = 0.012), whereas the mean CNV amplitude in the CD + AP group was not significantly different in the AP group (P = 0.168) and CD group (P > 0.05). Source localization results indicated altered activity in frontal-temporal regions. The CNV amplitude characteristics in the CD + AP group and AP group were more consistent and fluctuated around the baseline, indicating the absence of attention maintenance resulted in impairments in attention allocation and motor preparation in the CD + AP group and AP group.

Impulsivity Moderates the Effect of Neurofeedback Training on the Contingent Negative Variation in Autism Spectrum Disorder.

BackgroundThe contingent negative variation (CNV) is a well-studied indicator of attention- and expectancy-related processes in the human brain. An abnormal CNV amplitude has been found in diverse neurodevelopmental psychiatric disorders. However, its role as a potential biomarker of successful clinical interventions in autism spectrum disorder (ASD) remains unclear.MethodsIn this randomized controlled trial, we investigated how the CNV changes following an intensive neurofeedback training. Therefore, twenty-one adolescents with ASD underwent 24 sessions of slow cortical potential (SCP) neurofeedback training. Twenty additional adolescents with ASD formed a control group and received treatment as usual. CNV waveforms were obtained from a continuous performance test (CPT), which all adolescents performed before and after the corresponding 3-month long training period. In order to utilize all available neural time series, trial-based area under the curve values for all four electroencephalogram (EEG) channels were analyzed with a hierarchical Bayesian model. In addition, the model included impulsivity, inattention, and hyperactivity as potential moderators of change in CNV.ResultsOur model implies that impulsivity moderates the effects of neurofeedback training on CNV depending on group. In the control group, the average CNV amplitude decreased or did not change after treatment as usual. In the experimental group, the CNV changed depending on the severity of comorbid impulsivity symptoms. The average CNV amplitude of participants with low impulsivity scores decreased markedly, whereas the average CNV amplitude of participants with high impulsivity increased.ConclusionThe degree of impulsivity seems to play a crucial role in the changeability of the CNV following an intensive neurofeedback training. Therefore, comorbid symptomatology should be recorded and analyzed in future EEG-based brain training interventions.Clinical Trial Registrationhttps://www.drks.de, identifier DRKS00012339.

Common and separable behavioral and neural mechanisms underlie the generalization of fear and disgust

Generalization represents the transfer of a conditioned responses to stimuli that resemble the conditioned stimulus (CS). Previous studies on generalization of defensive avoidance responses have primarily focused on fear and have neglected disgust generalization, which represents a key pathological mechanism in some anxiety disorders. In the present study we examined common and distinct mechanisms of fear and disgust generalization by means of a fear or disgust multi-CS conditioning and generalization paradigm with concomitant event-related potential (ERPs) acquisition in n = 62 subjects. We demonstrate that compared to fear, disgust-relevant generalized stimuli (GS) elicited larger expectancy ratings and longer reaction times (RTs) reflecting stronger ratings of ‘risk’. On the electrophysiological level, increased P2 amplitudes were found in response to conditioned CS+ versus CS− across both domains, possibly reflecting higher motivational and attentional salience of aversive conditioned stimuli per se. Contingent negative variation (CNV) amplitude was significantly larger for disgust-CS+ than disgust-CS−, reflecting a stronger preparation of the disgust US. Additionally, we found that the contingent negative variation (CNV) fear generalization gradient, and CNV amplitude were increased with similarity to CS+. In contrast the CNV to disgust-GS did not differ and did not reflect disgust generalization. Together this may indicate that the CNV represents a highly fear-specific index for generalization learning. This study provides the first neurobiological evidence for common and distinct generalization learning in fear versus disgust suggesting that dysregulations in separable defensive avoidance mechanisms may underly different anxiety disorder subtypes.

Implicit emotion regulation improves arithmetic performance: An ERP study.

Available evidence suggests that emotions influence arithmetic, and explicit emotion regulation modulates the effect of anxiety on arithmetic performance. However, neural mechanisms by which implicit emotion regulation affects these phenomena remain unclear, particularly under distinct affective priming contexts. Twenty-two college students were required to perform multiple tasks in sequence, including an idioms matching task, a multiplication computational estimation task (MCE task), an emotion judgement task (EJ task), and an emotion assessment task (EA task). Behavioral performance was measured via accuracy and response time during the MCE task, and ratings of the EA task, while eletrophysiological response was measured via the contingent negative variation (CNV) elicited by completing the MCE task. Decreased response time and emotional intensity ratings were observed for priming emotion regulation idioms compared to priming neutral idioms. Priming emotion regulation idioms attenuated early CNV amplitudes under happiness priming, and attenuated both early and late CNV amplitudes under fear priming. These results suggested that implicit reappraisal and suppression are promising strategies to enhance arithmetic performance and alleviate the adverse effects of affective priming, especially under fear priming.

The Effect of Virtual Reality on Motor Anticipation and Hand Function in Patients with Subacute Stroke: A Randomized Trial on Movement-Related Potential.

Background Impaired cognitive ability to anticipate the required control for an upcoming task in patients with stroke may affect rehabilitation outcome. The cortical excitability of task-related motor anticipation for upper limb movement induced by virtual reality (VR) training remains unclear. Aims To investigate the effect of VR training on the cortical excitability of motor anticipation when executing upper limb movement in patients with subacute stroke. Methods A total of thirty-six stroke survivors with upper limb hemiparesis resulting from the first occurrence of stroke within 1 to 3 months were recruited. Participants were randomly allocated to the VR intervention group or conventional therapy group. Event-related potentials (ERPs) and electromyography (EMG) were used to simultaneously record the cortical excitability and muscle activities during palmar grasp motion. Outcome measures of the contingent negative variation (CNV) latency and amplitude, EMG reaction time, Upper Limb Fugl-Meyer Assessment (UL-FMA), Action Research Arm Test (ARAT), and National Institutes of Health Stroke Scale (NIHSS) were recorded pre- and postintervention. The between-group difference was analysed by mixed model ANOVA. Results The EMG onset time of the paretic hand in the VR group was earlier than that observed in the control group (t = 2.174, p = 0.039) postintervention. CNV latency reduction postintervention was larger in the VR group than in the control group (t = 2.411, p = 0.021) during paretic hand movement. The reduction in CNV amplitude in the VR group was larger in the VR group than in the control group (p < 0.001 for all electrodes except for C3) when executing paretic hand movement. ARAT and UL-FMA scores were significantly higher in the VR group than in the control group (p = 0.019 and p = 0.037, respectively) postintervention. No significant difference in the reduction in NIHSS was found between the VR and control groups (p = 0.072). Conclusions VR intervention is superior to conventional therapy to improve the cognitive neural process of motor anticipation and reduce the excessive compensatory activation of the contralesional hemisphere. The improvements observed in the cognitive neural process corroborated with the improvements in hand function.

Neurophysiological differentiation of personality disorders

The neurophysiological objectification of intranosological differentiation of main clusters (schizoid/paranoid and hysterical/emotionally unstable) within the typology of personality disorders (PD), as well as the differentiation of schizoid/paranoid PD and schizophrenia. Two groups of patients with PD participated in the study: PD1 - with schizoid/paranoid pattern (n=16), and PD2 - with hysterical/emotionally unstable pattern (n=18). The data were compared with the control group of healthy volunteers (n=86) and the group of schizophrenic patients (Sz, n=67). The analysis of four neurophysiological endophenotypes (measures of prepulse inhibition (PPI) of acoustic startle response and of P50 suppression, P300 amplitude, percentage of antisaccade errors) was carried out. The decrease of PPI and P50 suppression (measures of sensorimotor and sensory gating) relative to the control group was found both for Sz (p<0.01) and PD1 (p<0.05) groups. The highest P300 amplitude was observed in the control group, while the lowest values were observed in the Sz group (p<0.001); the values of PD1 and PD2 groups were intermediate. In all clinical groups percent of antisaccade errors was significantly higher compared to the control group (Sz - p<0.001; PD1 - p<0.05; PD2 - p<0.01). However, the level of the fronto-central cortical activation during antisaccade performance (estimated by contingent negative variation amplitude) was significantly reduced only in the Sz group (p<0.01), which is consistent with the concept of «hypofrontality» in schizophrenia. The changes associated with increased emotional reactivity were found in PD2 group only (P300 amplitude frontal maximum, asymmetry of error percent in antisaccade task). The study showed that two personality patterns in PD patients are related to the individual specificity of functional brain networks.

Effects of Electroacupuncture Combined With Psychological Intervention on Depressive Status and Contingent Negative Variation in Patients With Internet Addiction Disorder: A Randomized Controlled Trial.

Background: Depressive symptoms often accompany people with Internet addiction syndrome (IAD). Acupuncture has been found to have significant advantages in improving the severity and depressive symptoms of IAD. Contingent negative variation (CNV) is a common method to explore the mechanism of neurophysiology.Objective: The purpose of this study was to observe the efficacy of electroacupuncture (EA), psychological intervention (PI), and comprehensive intervention (CI) in the treatment of depression in Internet addiction disorder (IAD), and to observe the changes of contingent negative variation (CNV) in each group.Methods: One hundred and twenty subjects diagnosed with IAD were randomly assigned to the EA group, the PI group, or the CI group. They received EA, PI, or a combination of EA and PI for 40 days. The Internet Addiction Test (IAT), the Zung Self-rating Depression Scale (SDS), and the Hamilton Depression Scale (HAMD) were evaluated for all subjects at baseline, 20th, and 40th days of treatment, while CNV data were collected at baseline and 40th days of treatment.Results: Three treatments effectively reduced IAT, SDS, and HAMD scores, and the intergroup comparison showed that CI was superior to EA, while EA was superior to PI. CNV results indicated that the CNV amplitude increased in all three groups of IAD patients after treatment. The CNV latency of point A and A-S2' wave area of the EA group and the CI group did not change significantly after treatment. Only the A-S2' wave area of the PI group increased significantly compared with the baseline period. In addition, IAD's IAT score was positively correlated with SDS and HAMD score at baseline but negatively correlated with CNV latency. After treatment, only the change of HAMD score in the CI group was negatively correlated with amplitude.Conclusion: Our results demonstrate the efficacy of acupuncture and psychological intervention in the treatment of IAD from an electrophysiological perspective. Simultaneously, the increase in CNV amplitude might be the underlying neurophysiological mechanism by which CI improves depression and cognitive function in IAD patients.Clinical Trial Registration: ClinicalTrials.gov, identifier NCT02362698.

Similar CNV Neurodynamic Patterns between Sub- and Supra-Second Time Perception.

In the field of time psychology, the functional significance of the contingent negative variation (CNV) component in time perception and whether the processing mechanisms of sub- and supra-second are similar or different still remain unclear. In the present study, event-related potential (ERP) technology and classical temporal discrimination tasks were used to explore the neurodynamic patterns of sub- and supra-second time perception. In Experiment 1, the standard interval (SI) was fixed at 500 ms, and the comparison interval (CI) ranged from 200 ms to 800 ms. In Experiment 2, the SI was fixed at 2000 ms, and the CI ranged from 1400 ms to 2600 ms. Participants were required to judge whether the CI was longer or shorter than the SI. The ERP results showed similar CNV activity patterns in the two experiments. Specifically, CNV amplitude would be more negative when the CI was longer or closer to the memorized SI. CNV peak latency increased significantly until the CI reached the memorized SI. We propose that CNV amplitude might reflect the process of temporal comparison, and CNV peak latency might represent the process of temporal decision-making. To our knowledge, it is the first ERP task explicitly testing the two temporal scales, sub- and supra-second timing, in one study. Taken together, the present study reveals a similar functional significance of CNV between sub- and supra-second time perception.