P300 Differences Research Articles

Effects of Transcutaneous Auricular Vagus Nerve Stimulation on the P300: Do Stimulation Duration and Stimulation Type Matter?

Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has attracted increasing interest as a neurostimulation tool with potential applications in modulating cognitive processes such as attention and memory, possibly through the modulation of the locus-coeruleus noradrenaline system. Studies examining the P300 brain-related component as a correlate of noradrenergic activity, however, have yielded inconsistent findings, possibly due to differences in stimulation parameters, thus necessitating further investigation. In this event-related potential study involving 61 participants, therefore, we examined how changes in taVNS parameters, specifically stimulation type (interval vs. continuous stimulation) and duration, influence P300 amplitudes during a visual novelty oddball task. Although no effects of stimulation were found over the whole cluster and time window of the P300, cluster-based permutation tests revealed a distinct impact of taVNS on the P300 response for a small electrode cluster, characterized by larger amplitudes observed for easy targets (i.e., stimuli that are easily discernible from standards) following taVNS compared to sham stimulation. Notably, our findings suggested that the type of stimulation significantly modulated taVNS effects on the P300, with continuous stimulation showing larger P300 differences (taVNS vs. sham) for hard targets and standards compared to interval stimulation. We observed no interaction effects of stimulation duration on the target-related P300. While our findings align with previous research, further investigation is warranted to fully elucidate the influence of taVNS on the P300 component and its potential utility as a reliable marker for neuromodulation in this field.

Executive functions abilities in preschool-age children are negatively related to parental EF, screen-time and positively related to home literacy environment: an EEG study

ABSTRACT Environmental factors such as Home Literacy Environment (HLE), screen time, and parental executive functions (EF) may influence the development of the child’s EF. The purpose of this study was to determine the effect of these factors on behavioral and neurobiological measures of EF in 4-year-old children. Electroencephalogram (EEG) data were collected while children performed the Attention Network Task (ANT), showing a smaller difference between incongruent and congruent conditions is related to better EF abilities. Data were analyzed using an Event-Related Potential (ERP) technique focusing on the N200 and P300 components (reflecting executive control and orienting attention, respectively). N200 and P300 differences (delta) between amplitudes and latencies for the incongruent and congruent conditions were computed and correlated with child EF skills, HLE, screen exposure, and parental EF. Screen exposure was associated with lower EF in children and their parents. Additionally, smaller differences between N200 amplitudes and latencies for the incongruent vs. congruent conditions were associated with higher HLE scores. In contrast, greater differences between P300 amplitudes and latencies were related to longer screen time. HLE was positively associated with EF’s neurobiological (EEG) and behavioral measures, and screen time was negatively associated with these measures. This study also highlights the important relationship between parental EF (i.e., family predisposition) and EF’s neurobiological and behavioral measures in their children.

Reduced flanker P300 prospectively predicts increases in depression in female adolescents

Past research has found that P300 is smaller in depressed adults. Research examining P300 in relation to adolescent depression is more inconsistent; most studies fail to find P300 differences between currently depressed adolescents and controls. Previous studies have not examined the potential predictive utility of P300 in regard to adolescent depression. Therefore, the current study investigated the relationship between P300 amplitude and depression symptoms at baseline and two years later in a sample of 199 female adolescents. At baseline, participants completed measures of depression, followed by a speeded response task (flanker) while EEG was recorded. Two years later, participants completed the same depression measures. Reduced baseline P300 predicted increases in depression at two-year follow-up. Baseline P300 related particularly to two-year anhedonia and negative self-esteem symptoms. Our study suggest that reduced P300 amplitude can be utilized as a potential risk marker for adolescents at risk for developing increases in depressive symptoms.

Financial Incentive Does Not Affect P300 in the Complex Trial Protocol (CTP) Version of the Concealed Information Test (CIT) in Malingering Detection. II. Uninstructed Subjects.

Well-known research showed that the skin conductance response (SCR) of the Autonomic Nervous System (ANS) in the Concealed Information Test (CIT) is usually augmented in participants who are financially and motivationally incentivized to beat the CIT. This is not what happens with Reaction Time (RT)-based CITs, P300 CITs based on the 3-stimulus protocol, nor on the P300-based complex trial protocol for detection of malingering (however these tests differ from forensic CITs). The present report follows up the Rosenfeld et al. (1, 2) study of motivated malingerers instructed how to beat the test, with uninstructed motivated (paid and unpaid) and unmotivated (“simple malingering”) subjects, using episodic and semantic memory probes. The Test of Memory Malingering (TOMM) validated behavioral differences among groups. The “CIT effect” (probe-minus-irrelevant P300 differences) did not differ among incentive groups, although as previously, semantic memory-evoked P300s exceeded episodic memory evoked P300s. An effect of specific test-beating instructions was found to enhance the CIT effect for semantic information.

Item Roles Explored in a Modified P300-Based CTP Concealed Information Test

In this study, we introduced familiarity-related inducer items (expressions referring to the participant’s self-related, familiar details: “mine,” “familiar”; and expressions referring to other, unfamiliar details, e.g., “other,” “irrelevant”) to the Complex Trial Protocol version of the P300-based Concealed Information Test (CIT), at the same time using different item categories with various levels of personal importance to the participants (forenames, birthdays, favorite animals). The inclusion of inducers did not significantly improve the overall efficiency of the method as we would have expected considering that these inducers should increase awareness of the denial of the recognition of the probes (the true details of the participants), and hence the subjective saliency of the items (Lukács in J Appl Res Mem Cognit, 6:283–284, 2017a). This may be explained by the visual similarity of inducers to the probe and irrelevant items and the consequent distracting influence of inducers on probe-task performance. On the other hand, the CIT effect (probe-irrelevant P300 differences) was always lower for less personally important (low-salient) and higher for more personally important (high-salient) items.

P300 for the assessment of cognitive disorders in Chinese patients with Parkinson’s disease: a Meta-analysis

Objective To assess the clinical utility of P300 for the assessment of disorders in Chinese patients with Parkinson’s disease (PD) by meta-analysis. Methods Studies comparing the P300 between PD patients with different disorders (dementia, mild impairment (MCI), and no impairment; the former two were cognitive impairments , while the latter two were non-dementia ) and healthy controls were retrieved by searching within major Chinese and English databases. Studies, whose case and control groups were matched for age and gender, were rated as high quality. Weighted mean differences (WMDs) in P300 latency and amplitude between groups were calculated by using meta-analysis. Results In total, 23 studies were included and 20 of which were rated high quality. Demented PD patients had statistically significant longer P300 latency (WMD: 56.14, 95%CI: 19.06, 93.23) and lower amplitude (WMD: -1.30, 95%CI: -2.08, -0.51) than non-demented PD patients. PD patients with MCI had statistically significant longer P300 latency (WMD: 13.71, 95%CI: 5.13, 22.29) and lower amplitude (WMD: -1.25, 95%CI: -2.29, -0.21) than PD patients without disorders. However, no significant differences in P300 latency (WMD: 4.16, 95%CI: -13.85, 22.17) and amplitude (WMD: 0.23, 95%CI: -1.72, 2.17) were found between PD patients with dementia and MCI. Conclusion Among Chinese PD patients, there are significant P300 differences between those with dementia and without dementia, and between MCI and those without impairments, however, but no significant P300 differences between those with dementia and MCI. Key words: Parkinson’s disease; Dementia; Mild impairment; P300; Meta-analysis

Moderate financial incentive does not appear to influence the P300 Concealed Information Test (CIT) effect in the Complex Trial Protocol (CTP) version of the CIT in a forensic scenario, while affecting P300 peak latencies and behavior

Previous research indicated that the skin conductance response (SCR) of the Autonomic Nervous System (ANS) in the Concealed Information Test (CIT) is typically increased in subjects who are financially and otherwise incentivized to defeat the CIT (the paradoxical “motivational impairment” effect). This is not the case for RT-based CITs, nor for P300 tests based on the 3-stimulus protocol or Complex Trial Protocol for detection of cognitive malingering (although these are not the same as forensic CITs). The present report extends earlier studies of malingerers by running five groups of subjects (15–16 per group yielding 78 total) in a mock crime (forensic) scenario: paid (to beat the test) and unpaid, instructed and uninstructed, and simply guilty. There was no evidence that the “CIT effect” (probe-minus-irrelevant P300 differences) differed among groups, although behavioral differences among groups were seen.

Financial incentive does not affect P300 (in response to certain episodic and semantic probe stimuli) in the Complex Trial Protocol (CTP) version of the Concealed Information Test (CIT) in detection of malingering.

Previous research indicated that the skin conductance response of the autonomic nervous system in the Concealed Information Test (CIT) is typically increased in subjects who are financially and otherwise incentivized to defeat the CIT (the paradoxical "motivational impairment" effect). This is not the case for RT-based CITs, nor P300 tests based on the three-stimulus protocol for detection of cognitive malingering (although these are not the same as CITs). The present report is the first attempt to study the effect of financial motivation on the P300-based Complex Trial Protocol using both episodic and semantic memory probe and irrelevant stimuli. The Test of Memory Malingering (TOMM) was used to validate behavioral differences between the two groups we created by offering one (paid) group but not another (unpaid) group a financial reward for beating our tests. Group behavioral differences on the TOMM did confirm group manipulations. Probe-minus-irrelevant P300 differences did not differ between groups, although as previously, semantic memory-evoked P300s were larger than episodic memory-evoked P300s.

Decentering the Self? Reduced Bias in Self- vs. Other-Related Processing in Long-Term Practitioners of Loving-Kindness Meditation.

Research in social neuroscience provides increasing evidence that self and other are interconnected, both on a conceptual and on an affective representational level. Moreover, the ability to recognize the other as “like the self” is thought to be essential for social phenomena like empathy and compassion. Meditation practices such as loving-kindness meditation (LKM) have been found to enhance these capacities. Therefore, we investigated whether LKM is associated to an increased integration of self–other-representations. As an indicator, we assessed the P300 event-related potential elicited by oddball stimuli of the self-face and a close other’s face in 12 long-term practitioners of LKM and 12 matched controls. In line with previous studies, the self elicited larger P300 amplitudes than close other. This effect was reduced in the meditation sample at parietal but not frontal midline sites. Within this group, smaller differences between self- and other-related P300 were associated with increasing meditation practice. Across groups, smaller P300 differences correlated with self-reported compassion. In meditators, we also investigated the effect of a short LKM compared to a control priming procedure in order to test whether the state induction would additionally modulate self- vs. other-related P300. However, no effect of the priming conditions was observed. Overall, our findings provide preliminary evidence that prolonged meditation practice may modulate self- vs. other-related processing, accompanied by an increase in compassion. Further evidence is needed, however, to show if this is a direct outcome of loving-kindness meditation.

Greater sensitivity of the P300 component to bimodal stimulation in an event-related potentials oddball task

ObjectiveStudies that explore neurophysiological correlates of psychiatric disorders have commonly used event-related potentials during a visual or an auditory oddball task with the main results being changes in the P300 component. In the present study, a bimodal oddball design with synchronized pairs of audio–visual stimuli was used to further improve the clinical sensitivity of the P300. MethodsTwo groups of healthy participants, one consisting of students displaying anxious–depressive tendencies and the other of control students, completed visual, auditory and two kinds of audio–visual oddball task (one using emotional stimuli and the other using geometrical figures and simple sounds), in which they had to detect deviant rare stimuli among more frequently presented standard stimuli as quickly as possible. Behavioral performance and P300 data were analyzed. ResultsThe subjects with anxious and depressive tendencies had lower P300 amplitudes than controls, but only in the bimodal tasks. ConclusionsAlthough the two groups differed in their levels of anxiety and depression, only the bimodal tasks were able to identify these differences. SignificancesThese results suggest that a bimodal oddball design should be used in future studies to increase the sensitivity of P300 differences for differentiating between healthy participants and those with clinical symptoms.

A novel countermeasure against the reaction time index of countermeasure use in the P300-based complex trial protocol for detection of concealed information

A P300 deception detection protocol was tested using simultaneous versus serial countermeasures and stimulus acknowledgment responses. Previously, P300 showed recognition and elevated reaction time identified countermeasure use. Probe-irrelevant P300 differences were significant in both countermeasure groups and control group. Detection rates were 11/12 for controls, 10/12 for serial countermeasure users, and 11/13 for simultaneous countermeasure users. Reaction time detected countermeasure use in serial responders, but not simultaneous responders. The simultaneous response reaction times were indistinguishable from controls.

The effects of asymmetric vs. symmetric probability of targets following probe and irrelevant stimuli in the complex trial protocol for detection of concealed information with P300

The complex trial protocol (CTP, [J.P. Rosenfeld, E. Labkovsky, M. Winograd, M.A. Lui, C. Vandenboom & E. Chedid (2008), The complex trial protocol (CTP): a new, countermeasure-resistant, accurate P300-based method for detection of concealed information. Psychophysiology, 45, 906–919.]) is a sensitive, new, countermeasure-resistant, P300-based concealed information protocol in which a first stimulus (Probe or Irrelevant) is followed after about 1.4–1.8 s by a Target or Non-Target second stimulus within one trial. It has been previously run with a potentially confounding asymmetric conditional probability of Targets following Probes vs. Irrelevants. This present study compared asymmetric vs. symmetric conditional probability groups and found no significant differences in detection rates or Probe-minus-Irrelevant P300 differences between groups. Group differences were seen in error rates and reaction times (RT) to second stimuli. These differences were, however, not diagnostic for deception vs. truth-telling, and were attributable to response perseveration.

Neurophysiological Distinction between Schizophrenia and Schizoaffective Disorder.

Schizoaffective disorder (SA) is distinguished from schizophrenia (SZ) based on the presence of prominent mood symptoms over the illness course. Despite this clinical distinction, SA and SZ patients are often combined in research studies, in part because data supporting a distinct pathophysiological boundary between the disorders are lacking. Indeed, few studies have addressed whether neurobiological abnormalities associated with SZ, such as the widely replicated reduction and delay of the P300 event-related potential (ERP), are also present in SA. Scalp EEG was acquired from patients with DSM-IV SA (n = 15) or SZ (n = 22), as well as healthy controls (HC; n = 22) to assess the P300 elicited by infrequent target (15%) and task-irrelevant distractor (15%) stimuli in separate auditory and visual ”oddball” tasks. P300 amplitude was reduced and delayed in SZ, relative to HC, consistent with prior studies. These SZ abnormalities did not interact with stimulus type (target vs. task-irrelevant distractor) or modality (auditory vs. visual). Across sensory modality and stimulus type, SA patients exhibited normal P300 amplitudes (significantly larger than SZ patients and indistinguishable from HC). However, P300 latency and reaction time were both equivalently delayed in SZ and SA patients, relative to HC. P300 differences between SA and SZ patients could not be accounted for by variation in symptom severity, socio-economic status, education, or illness duration. Although both groups show similar deficits in processing speed, SA patients do not exhibit the P300 amplitude deficits evident in SZ, consistent with an underlying pathophysiological boundary between these disorders.

P300 differences exist between Tourette's syndrome with and without attention deficiency and hyperactivity disorder in children

Objective: To study the characteristics of P300 in Tourette's syndrome (TS) with and without attention deficiency and hyperactivity disorder (ADHD). Method: Auditory evoked P300 were recorded in 19 TS only (TS–ADHD) children, 15 TS with ADHD (TS + ADHD) children and 20 unaffected control subjects, and their waveforms, amplitudes, latencies and topographies were compared at Fz, Cz, C3, C4 and Pz. Results: The TS + ADHD group showed shorter latencies than control subjects at all electrode sites (P<0.05 or 0.01), and the TS–ADHD group at CZ and PZ (P<0.05); however, there was no significant difference between control subjects and the TS–ADHD group. The TS–ADHD group showed smaller amplitudes than the control group at all electrode sites (P<0.05), and the TS + ADHD group at Cz (P<0.05); however, there were no significant differences between control subjects and the TS + ADHD group. There was no significant difference in the prevalence of abnormal waveforms between the control, TS, TS–ADHD and TS + ADHD groups, but there were significant differences in the variability of localization of P300 between the control and the TS group (P=0.003), control and TS + ADHD groups (P=0.000), and the TS–ADHD and TS + ADHD groups (P=0.039). P300 in the TS + ADHD group tended to spread out to the left and that of the TS–ADHD group tended to spread out to the right. Conclusions: P300 differences exist between TS–ADHD and TS + ADHD in children. These suggested that establishment different development defects or delay of communications between different structures rather than a delay in maturation of the structures themselves may be involved in TS + ADHD and TS–ADHD children and ADHD symptoms in TS patients are likely a trait rather than adventitious or acquired within the TS syndrome.

Alzheimers Disease and P300: Review and Evaluation of Task and Modality

Early stage Alzheimer disease patients and matched elderly unaffected controls (n = 16/group) were evaluated with the P300 event-related brain potential (ERP). All subjects performed four oddball tasks that varied systematically in task difficulty and were each presented in the auditory and visual modalities. P300 amplitude was smaller and peak latency longer for the Alzheimer patients compared to elderly control subjects across tasks and modalities. P300 differences between Alzheimer patients and controls were largest for the relatively easy tasks, with little influence of stimulus modality observed. The results suggest that the P300 brain potential is sensitive to Alzheimer's disease processes during its early stages, and that easily performed stimulus discrimination tasks are the clinically most useful. Theoretical and practical implications are reviewed.

Age-related cognitive decline in the menopause: effects of hormone replacement therapy on cognitive event-related potentials

Objective: Although epidemiological and clinical studies suggest that hormone replacement therapy (HRT) may protect against cognitive disorders and neurodegenerative diseases, the relation between estrogen and cognition in postmenopausal women remains controversial. Methods: In a double-blind placebo-controlled, parallel group design study the effects of HRT with the estrogen–progestogen combination Presomen 1.25 compositum ® (1.25 mg equine conjugated estrogens administered for 21 days plus the progestogen 5 mg medrogeston given for 11 days) on event-related potentials (ERPs) in postmenopausal patients with age-related cognitive decline (DSM-IV code 780.9, ICD-10 code R 41.8) were investigated. After a pre-drug comparison with age-matched normal postmenopausal controls, 48 psychotropic drug-free patients aged 60 ± 6 years were randomized to receive either placebo or verum for 4 months. ERPs were recorded before as well as on the 91–92 days of the study, which thus fell into the estrogen phase of the treatment during the fourth cycle. Results: At baseline, patients showed a lengthening of P300 latency and an attenuation of P300 amplitudes as compared with normal controls. After HRT with Presomen, a significant shortening of P300 latency as compared with placebo was observed. Conclusions: The baseline P300 differences suggest that in the patient group the aging process was advanced, while after HRT with Presomen a significant improvement and normalization of information processing as indexed by P300 was observed.

Visual P300 Effects Beyond Symptoms in Concussed College Athletes

In order to assess whether cerebral anomalies may be observed in the absence of clinical symptoms, the current study compared the effects of concussions on attentional capacities (reaction times, accuracy) and Event-Related Potentials (ERPs) in concussed athletes with (n = 10) or without (n = 10) symptoms as well as in athletes who never had a concussion (n = 10). The P300 response was recorded from 28 electrodes during a modified visual oddball paradigm. Participants were instructed to press a key upon the appearance of the frequent stimuli as well as when a rare nontarget stimulus followed the frequent one. The other key was to be pressed when the subsequent rare stimuli (rare target) appeared until a frequent one reappeared. The symptomatic athletes displayed longer reaction times than the other two groups of athletes. The P300 amplitude to the rare target stimuli was significantly more attenuated in the symptomatic athletes than in the other two groups. Moreover, the P300 amplitude varied inversely with the severity of postconcussion symptoms but was not influenced by time elapsed since injury. Although the clinical significance of the P300 differences shown by the symptomatic athletes is still uncertain, the results do indicate that symptom severity may be a crucial indicator of functional impairments following mild traumatic brain injury.

Substance abuse-related P300 differences in response to an implicit memory task

The current study examined electrophysiological measures of cognitive efficiency in alcoholics and controls using a negative priming paradigm derived from DeSchepper and Treisman (J. Exp. Psychol. Learn. Mem. Cog. 22 (1996) 27). In this task, sets of novel shapes were presented: Two overlapping green and red shapes on the left and a single white shape on the right. Participants were instructed to ignore the red shape, but to determine whether the green shape was the same as or different from the white shape. On primed trials, previously red (to be ignored; i.e., irrelevant) shapes became green (relevant) shapes in a second component of the task. Participants who were capable of ignoring irrelevant stimuli were expected to experience more difficulty in the primed condition. Therefore, we predicted that, if alcohol-related impairment in cognitive efficiency is due to inability to respond “appropriately” (i.e., ignore irrelevant stimuli), alcoholics would experience less negative priming than normal controls. Both amplitude and latency of the P300 component of the event-related potential were measured in response to each trial condition. Using a 2×2 (group×condition) ANOVA with repeated conditions, a significant pattern of group×condition interactions was observed at right frontal, F4 ( p=.05) and central parietal, Pz ( p=.03) electrode sites on measures of P300 amplitude. A significant group×condition latency interaction was observed at the central parietal electrode, Pz ( p=.006). Overall, controls exhibited increased P300 amplitude and latency in response to negatively primed trials. As predicted, alcoholics did not demonstrate this pattern, a finding consistent with alcohol-related cognitive inefficiency.

Scaled P300 Scalp Distribution Correlates of Verbal Deception in an Autobiographical Oddball Paradigm: Control for Task Demand

Abstract Subjects participated in two trial blocks of an autobiographical oddball paradigm. In the first block, 14% of the stimuli were the subject's phone number, 86% were other, meaningless numbers. Subjects responded yes or no, verbally and truthfully. In the second block, stimuli were dates, and the oddball was the subject's birthdate. Subjects again responded verbally, but dishonestly on about 50% of the trials and truthfully on the other 50%. Reaction times differed between the first and the second blocks, but not between the honest and dishonest trials of the second block. P300 amplitude was reduced in dishonest trials of the second block. Honest trials of both blocks had similar P300 amplitudes. Scaled scalp distributions were the same for honest trials of both blocks, but differed between honest and dishonest trials of the second block. There were no latency effects. The results are discussed from the viewpoint that task demand effects do not mediate the P300 differences between honest and dishonest responses.

Effects of alcoholism, anxiety and depression on P300 in women: a pilot study.

The present investigation was designed for the purpose of revealing functional brain impairments associated with alcoholism, anxiety and depression. The subjects were 56 women, with an average (SD) age of 34.8 (7.3) years. None reported a history of neurological or major medical disorders, or drug abuse. Twenty-nine of the women met DSM-IV lifetime criteria for a diagnosis of alcohol abuse or dependence. Twenty-five women reported mild or higher levels of anxiety, as indexed by a Beck Anxiety Inventory (BAI) score greater than 7. Electroencephalographic activity was recorded while subjects performed a visual ("oddball") selective attention task comprised of rare target, rare nontarget and frequent nontarget stimuli. P300 event-related potentials elicited by the rare target and rare nontarget stimuli were analyzed. The initial analysis was structured as a 2 (alcoholism) by 2 (anxiety) factorial. Analyses revealed no significant effects of alcoholism on P300. However, women reporting a BAI score greater than 7 exhibited significantly smaller P300 amplitudes than their nonanxious counterparts. The P300 decrement remained significant when depression level (Beck Depression Inventory [BDI-II]) and age were entered as covariates. A separate analysis was conducted in which the 56 subjects were classified by alcoholism and depression level (BDI-II score < or =13 vs >13). The analysis revealed no significant P300 differences associated with these factors. It is hypothesized that anxiety might play a role in mediating or amplifying the P300 decrements that have been attributed to alcoholism and depression in women. Additional and more comprehensive studies are needed to discern the validity ofthis hypothesis.