Changes In P300 Amplitude Research Articles

Changes in P300 amplitude to negative emotional stimuli correlate with treatment responsiveness to sertraline in adolescents with depression

ObjectiveAdolescents with depression is characterized by high rates of recurrence and functional impairment, with a significant association with suicide risk. Antidepressants are commonly prescribed to treat depression, yet few reproducible neurobiological markers for depression and antidepressant treatment response have been identified. Therefore, discovering a stable and reliable neurobiological marker holds significant value for both the clinical diagnosis and treatment of depression in adolescents. MethodsOne hundred and seven patients with major depressive disorder (MDD group, 30 males, 77 females, mean age: 14.80 years), and 25 healthy subjects (HC group, 13 males, 12 females, mean age: 15.72 years) were recruited to perform a two-choice oddball task related to negative emotional cues. All participants completed a self-administered questionnaire to gather demographic information. A trained psychiatrist administered the Hamilton Depression Scale (HAMD-17) to assess depression severity. Of the 107 adolescents with depression, 61 received antidepressant medication for 8 weeks, and 61 of these patients were followed up. Multichannel EEG was recorded continuously from 64 scalp electrodes using the Curry 8 system. EEG signal preprocessing and analysis was performed offline using the EEGLAB toolbox in MATLAB. The ERP component characteristics associated with emotional processing were extracted from the difference waves and statistically analyzed. ResultsAdolescents with depression exhibited significantly larger P300 amplitudes than healthy controls in response to both neutral and negative emotional cues. Following sertraline treatment, both depression scores and P300 amplitudes decreased significantly in adolescents with depression. Moreover, a strong positive correlation was observed between changes in depression scores and changes in P300 amplitude in response to negative emotional cues before and after treatment. ConclusionsChanges in neural reactivity to negative emotional stimuli among adolescents with depression can be selectively modulated by sertraline and are significantly associated with improvements in depressive symptoms. SignificanceChanges in P300 amplitude to negative emotional stimuli significantly correlate with treatment responsiveness to sertraline in adolescents with depression.

Mobile EEG for the study of cognitive-motor interference during swimming?

Research on brain function in natural environments has become a new interest in cognitive science. In this study, we aim to advance mobile electroencephalography (EEG) participant and device mobility. We investigated the feasibility of measuring human brain activity using mobile EEG during a full-body motion task as swimming, by the example of cognitive-motor interference (CMI). Eleven participants were given an auditory oddball task while sitting and swimming, with mobile EEG recording ongoing brain activity. Measures of interest were event-related potentials (ERPs) elicited by experimental stimuli. While the auditory N100 was measured to verify signal quality, the P300 to task-relevant stimuli served as a marker of CMI effects. Analyzes were first performed within subjects, while binomial tests assessed the proportion of significant effects. Event-related changes in the time-frequency domain around turns during swimming were analyzed in an exploratory fashion. The successful recording of the N100 in all conditions shows that the setup was functional throughout the experiment. Regarding CMI, we did not find reliable changes in P300 amplitude in different motor settings in all subjects. However, we found plausible modulations in the alpha/mu and beta bands before and after turns. This study shows that it is generally feasible to measure mobile EEG in the time and time-frequency domain in an aquatic environment while subjects are freely moving. We see promising potential in the use of mobile EEG in extreme settings, advancing toward the application of mobile EEG in more real-life situations.

Influences of age and pubertal development on P300 amplitude trajectory across two years in female adolescents

The P300 event-related potential (ERP) has been extensively studied across the human lifespan. However, many studies examining age-related effects are cross-sectional, and few have considered the unique role that pubertal development may have on P300 developmental trajectories. The current study examined whether age, pubertal maturation or their interaction predicted changes in P300 amplitude over two years among 129 females between the ages of 8 and 15 years at baseline. Participants completed a flanker task while EEG was recorded at a baseline and two-year follow-up visit. Both baseline age and increased pubertal development were associated with smaller P300 amplitude at follow-up. However, the influence of age was qualified by an interaction between age and pubertal maturation: among younger girls only, increased pubertal development predicted decreases in P300, whereas decreased pubertal development predicted increases in P300. These data indicate that pubertal timing impacts neurodevelopmental changes in P300 amplitude – such that high versus low pubertal development among 8- to 10-year-old girls predicted differential trajectories of neural activity. In light of links between reduced P300 and mental health disorders, such as depression, future studies might examine whether neurodevelopmental changes influenced by early-onset pubertal development could account for increases in these mental health problems.

In-clinic event related potentials after sports concussion: A 4-year study.

PURPOSE: Electrophysiological event-related potentials (ERP’s) have been reported to change after concussion. The objective of this study is to use a simple 2-tone auditory P300 ERP in routine clinical settings to measure changes from baseline after concussion and to determine if these changes persist at return to play when other standard measures have normalized.METHODS: Three-hundred sixty-four (364) student athletes, aged 17–23 years, participating in contact sports were tracked over consecutive years. In this blinded study P300, plus physical reaction times and Trail Making tests, were collected alongside standard clinical evaluations. Changes in these measures after concussion were compared to clinical outcomes over various stages of post-injury recovery.RESULTS: Concussed players experienced significant reaction time and/or P300 amplitude changes compared to pre-concussion baseline measurements ( 0.005). P300 changes persisted in 38% of the players after standard measures, including reaction times, had cleared. Many of those players slow to normalize were part of the sub-concussive symptom group and/or appeared more prone to repeat concussions.CONCLUSION: These data suggest significant P300 amplitude changes after concussion that are quantifiable and consistent. These changes often normalized slower than other standard assessments. More data are needed to determine if slow normalization relates to sub-concussive or repeated events.

Agreeableness modulates group member risky decision-making behavior and brain activity

When facing difficult decisions, people typically believe that “two heads are better than one”. However, findings from previous studies are inconsistent regarding the advantages of decision-making in groups as compared to individual decision-making. We hypothesize that personality traits may modulate risk-taking behavior and brain activity changes during group decision-making. In this study, we used event-related potentials (ERP) with a well-validated balloon analogue risk task (BART) paradigm to examine the relationships between personality traits, decision-making behavior, and brain activity patterns when a cohort of male participants make decisions and take risks both in groups and in isolation. We found significantly increased risk-taking behavior and reduced P300 component during group decision-making as compared to individual decision-making only for participants with high Agreeableness, but not for those with low Agreeableness. Moreover, Agreeableness scores correlated with risk-taking behavior and P300 amplitude changes in group decisions. These findings suggest that Agreeableness personality modulates risk-taking behavior and brain activity when people make decisions in groups, which have implications for future group decision research and practice.

EEG P300 Amplitude Tracks mTBI Changes

To investigate the changes in P300 amplitude during the recovery phase following concussion. Do the neuro physiological markers of voltage amplitude and delay time obtained from cortical auditory P300 testing track physical signs and symptoms following concussion?

Vigilance state fluctuations and performance using brain–computer interface for communication

ABSTRACTThe effect of fatigue and drowsiness on brain–computer interface (BCI) performance was evaluated. Twenty healthy participants performed a standardized 11-min calibration of a Rapid Serial Visual Presentation BCI system 5 times over 2 h. For each calibration, BCI performance was evaluated using area under the receiver operating characteristic curve (AUC). Self-rated measures were obtained following each calibration including the Karolinska Sleepiness Scale and a standardized boredom scale. Physiological measures were obtained during each calibration including P300 amplitude, theta power, alpha power, median power frequency, and eye-blink rate. There was a significant decrease in AUC over the five sessions. This was paralleled by increases in self-rated sleepiness and boredom and decreases in P300 amplitude. Alpha power, median power frequency, and eye-blink rate also increased but more modestly. AUC changes were only partly explained by changes in P300 amplitude. There was a decrease in BCI performance over time that related to increases in sleepiness and boredom. This worsened performance was only partly explained by decreases in P300 amplitude. Thus, drowsiness and boredom have a negative impact on BCI performance. Increased BCI performance may be possible by developing physiological measures to provide feedback to the user or to adapt the classifier to state.

Utility of P300 ERP in monitoring post-trauma mental health: A longitudinal study in military personnel returning from combat deployment

Military service members (SMs) returning from combat are at high risk of developing neuropsychiatric conditions such as posttraumatic stress disorder (PTSD) and major depression. Symptom dynamics following reintegration into civilian life may be magnified over time such that some SMs present with delayed onset and may not reach a diagnostic threshold for months to years. Monitoring the trajectory of mental health in the aftermath of combat trauma can therefore be particularly important in enhancing diagnosis. In this study, we investigated the possible utility of the P300 event-related potential (ERP) as an objective marker for monitoring post-trauma mental health. SMs recently returned from a combat deployment were recruited to undergo a baseline assessment, with subsequent follow-up assessment at 6 or 12 months later. At each assessment, ERPs were recorded using a conventional visual oddball task and a set of psychological scores assessing PTSD, depression, and psychosocial functioning were obtained. We observed that the individuals with overall improved psychological scores at follow-up had increased P300 amplitude and shortened P300 latency, and the individuals with overall worsened psychological scores at follow-up had prolonged P300 latency. The degree of change in aggregate psychological score was significantly correlated with the magnitude of change in P300 amplitude (r = −0.72, p < 0.0001) and latency (r = 0.42, p = 0.0201). These findings suggest that the P300 may be utilized as a quantitative biomarker for tracking the changes of mental health longitudinally. It may offer clinicians an objective tool for the assessment of the dynamics of mental health following trauma, and perhaps also for monitoring recovery during treatment.

State and trait markers of emotionally charged visual event‐related potentials (P300) in drug‐naïve schizophrenia

In the present study, we investigated the changes in P3 component in the emotionally charged visual event-related potentials (ERP) in 30 drug-naïve schizophrenic patients for up to 1 year. Visual oddball event-related potential was recorded from six recording sites for crying baby or smiling baby photographs. ERP were recorded before the treatment (session 1 [S1]), after 3 months (session 2 [S2]), and after 12 months (session 3 [S3]), as well as in 30 healthy subjects. Before taking medicine, there were no significant differences in the P300 amplitude between viewing photographs of a crying and a smiling baby. The P300 amplitude was significantly larger at S2 and S3 than at S1 for a crying baby, while there was no significant difference among sessions for a smiling baby after medication. A significant difference of the P300 amplitude was only observed between S3 and healthy subjects for a smiling baby. The P300 latency only when viewing a smiling face became significantly longer at S3 than those at S1 and S2. A significant negative correlation was obtained between the P300 amplitude changes upon viewing crying faces and negative syndrome score changes at the Pz site. The P300 amplitude induced by crying-face stimuli may be a state marker and the P300 amplitude caused by smiling-face stimuli may be a trait marker during recovery in schizophrenic patients. Atypical antipsychotic medications may be useful and may recover cognitive function reflected by the emotionally charged visual P300 components in schizophrenic patients.

Gray matter alterations related to P300 abnormalities in subjects at high risk for psychosis: Longitudinal MRI-EEG study

BackgroundPsychotic disorders are characterized by gray matter and volumetric and electrophysiological abnormalities. The relationship between these factors in the onset of psychotic illness is unclear. MethodsEighty English-native right-handed subjects (39 subjects at ultra high risk for psychosis “ARMS” and 41 healthy volunteers) were scanned with MRI, and studied using EEG during an oddball task. Both assessments were performed at first clinical presentation. The ARMS subjects were then followed clinically, with the MRI and EEG assessments repeated in a subgroup of each sample. ResultsThe P300 amplitude at presentation was significantly lower in the ARMS subjects than in controls. At baseline, the ARMS group showed reduced gray matter volume relative to controls in the right superior frontal gyrus, left medial frontal gyrus, left inferior frontal gyrus, right orbital gyrus and right supramarginal gyrus. Transition to psychosis (26%) was associated with reduced gray matter in the right inferior parietal lobule and in the left parahippocampal gyrus. Within the ARMS group, there was a positive correlation between P300 amplitude and gray matter volume in the right supramarginal gyrus. A significant group by P300 by gray matter interaction was detected in the left medial frontal gyrus. Longitudinal assessment revealed progressive gray matter alterations in prefrontal and subcortical areas of the ARMS but no significant changes in P300 amplitude over time. ConclusionsP300 abnormalities in the ARMS are related to alterations in regional gray matter volume and represent a correlate of an increased vulnerability to psychosis.

Documenting, modelling and exploiting P300 amplitude changes due to variable target delays in Donchin's speller

The P300 is an endogenous event-related potential (ERP) that is naturally elicited by rare and significant external stimuli. P300s are used increasingly frequently in brain–computer interfaces (BCIs) because the users of ERP-based BCIs need no special training. However, P300 waves are hard to detect and, therefore, multiple target stimulus presentations are needed before an interface can make a reliable decision. While significant improvements have been made in the detection of P300s, no particular attention has been paid to the variability in shape and timing of P300 waves in BCIs. In this paper we start filling this gap by documenting, modelling and exploiting a modulation in the amplitude of P300s related to the number of non-targets preceding a target in a Donchin speller. The basic idea in our approach is to use an appropriately weighted average of the responses produced by a classifier during multiple stimulus presentations, instead of the traditional plain average. This makes it possible to weigh more heavily events that are likely to be more informative, thereby increasing the accuracy of classification. The optimal weights are determined through a mathematical model that precisely estimates the accuracy of our speller as well as the expected performance improvement w.r.t. the traditional approach. Tests with two independent datasets show that our approach provides a marked statistically significant improvement in accuracy over the top-performing algorithm presented in the literature to date. The method and the theoretical models we propose are general and can easily be used in other P300-based BCIs with minimal changes.

Effect of perospirone on P300 electrophysiological activity and social cognition in schizophrenia: A three-dimensional analysis with sLORETA

The purpose of this study was to determine if perospirone, a second generation antipsychotic drug and partial agonist at serotonin-5-HT 1A receptors, enhances electrophysiological activity, such as event-related potentials (ERPs), in frontal brain regions, as well as cognitive function in subjects with schizophrenia. P300 current source images were obtained by means of standardized low resolution brain electromagnetic tomography (sLORETA) before and after treatment with perospirone for 6 months. Perospirone significantly increased P300 current source density in the left superior frontal gyrus, and improved positive symptoms and performance on the script tasks, a measure of verbal social cognition, while verbal learning memory tended to be improved. There was a significant correlation between the changes in P300 amplitude on the left frontal lead and those in social cognition. These results suggest the changes in three-dimensional distribution of cortical activity, as demonstrated by sLORETA, may mediate some of the actions of antipsychotic drugs. The distinct cognition-enhancing profile of perospirone in patients with schizophrenia may be related to its actions on 5-HT 1A receptors.

Changes of Brain Potentials in Response to Smoking-Induced Stimuli in Smokers

Changes in P300 amplitude were used as an indicator of reactivity to smoking-related stimuli in smokers. The amplitude of P300--a component of event-related brain potentials (ERPs) elicited by 10 smoking-related (craving), 10 antismoking (aversive) and 10 neutral stimuli-- was recorded in smokers (n=10) and nonsmokers (n=10). Electroencephalography (EEG) data were obtained by the Laxtha EEG-monitoring device in the EEG recording room, and were recorded at F3, F4, C3, and C4. Three-way repeated-measures analysis of variance (ANOVA) was computed on the P300 amplitudes. The factors were group (smokers, nonsmokers), stimulus (craving, aversive, neutral), and electrode location (F3, F4, C3, and C4). The main effects of stimulus were significant, but the group effects did not show significant interactions with other factors. An interesting observation was the similarity between P300 waveforms for craving and aversive stimuli in smokers. These findings could indicate that the antismoking-related response is similar to the smoking-related one.

The effect of perospirone on auditory P300 in schizophrenia: A preliminary study

The present study was performed to determine the effect of perospirone, a novel antipsychotic drug with D 2/5-HT 2A antagonist and partial 5-HT 1A agonist properties, on auditory P300 in eight patients with chronic schizophrenia. Switching to an equivalent dose of perospirone from prior antipsychotic medication was associated with a significant improvement in the negative symptoms of the positive and negative syndrome scale (PANSS). The change in P300 amplitude following a switch to perospirone correlated significantly with the improvement of general psychopathology symptoms, as well as with the change in scores on items of delusions, hallucinatory behavior, emotional withdrawal, depression, poor attention, and disturbance of volition. These results suggest that clinical improvement in response to perospirone in some patients may, at least in part, be mediated through cognitive change indexed by P300 in chronic schizophrenia.

P300 development during adolescence: Effects of DRD2 genotype

Objective Young boys at high risk for alcoholism by having a family history of alcoholism (FH+) have lower amplitude of the visual P300 event-related scalp potential. They have also been reported to have a slowing in the rate of P300 amplitude change during adolescence. The present study examined whether the change in P300 amplitude during adolescence in sons of alcoholics and nonalcoholics is affected by D2 dopamine receptor (DRD2) polymorphism. Methods P300 was elicited with a visual discrimination task from 71 adolescent sons of alcoholics and social drinkers (Time 1, T1). The task was readministered 2 years later (Time 2, T2). Comparisons were made between boys who had the DRD2 A1 allele (A1+) and boys who did not (A1−), and between boys with one or both parents being alcoholic (FH+) and boys having no alcoholic parents (FH−). Results Discrimination task accuracy was lowest in the highest risk group (A1+, FH+) at T1, and highest in the lowest risk group (A1−, FH−) at T2, producing a significant interaction of allelic group×family history group×session. Reaction time was faster at T2 than T1, and this effect was larger in FH−boys (125 ms) than FH+boys (40 ms). Overall, the behavioral results suggest mild performance deficits on the discrimination task are associated with higher risk for alcoholism. In both testing sessions, P300 attained larger amplitudes in sons of nonalcoholics than sons of alcoholics. At T2 compared to T1, both the latency and amplitude of the P300 were decreased. However, while the developmental P300 latency effect was equivalent in both the A1+and A1− allelic groups, the P300 amplitude reduction during adolescence, measured both in response to targets and in target minus non-target subtraction waveforms, was only found in boys with the A1− allele. Conclusion Differences in the developmental course of P300 amplitude over the course of adolescence are dependent on DRD2 polymorphism. Significance These results suggest the importance of genetic determinants of the dopaminergic system in understanding the P300 as a risk marker for substance abuse using an integrative developmental perspective.

Long-Term Olanzapine Treatment and P300 Parameters in Schizophrenia

The well-known amplitude reduction of the P300 appears to be unaffected by the treatment with classical antipsychotics in schizophrenia, whereas the effects of atypical neuroleptics on this event-related potential are less understood. The study of these changes could help in deciding whether the P300 amplitude reduction in schizophrenia is a trait or state marker of that illness and in better describing the effect of atypical antipsychotics on altered cognitive functions. We present a prospective longitudinal study of P300 amplitude and latency before and after 6 months’ treatment with olanzapine in 11 patients with schizophrenia. A healthy control group (n = 30) was also studied. Overall, no significant changes, either in amplitude or in latency as measured at Pz and Fz electrodes, were found when comparing the pre- and postolanzapine conditions, despite the overall improvement in positive and negative symptoms. Nevertheless a direct specific association was observed between a P300 amplitude increase with olanzapine and the improvement in negative symptoms. These data would suggest that P300 amplitude reduction in schizophrenia may be relatively independent from clinical state and treatment, thus constituting a trait marker of schizophrenia. Our data also suggest that, in addition to this, some further changes in P300 amplitude might depend on the clinical state of the patients.

Trajectories of alcohol use and electrophysiological and morphological indices of brain development: distinguishing causes from consequences.

Alcoholism is a major public health problem. Patterns of drinking during adolescence can influence the likelihood of this outcome. Both environmental variation and familial/genetic susceptibility play important roles in this process. While there is some evidence to suggest that metabolic factors play a role in whether some individuals are protected from developing alcohol problems, there is substantial reason to look for cognitive factors that are associated with increased susceptibility. Developmental trajectories for information processing that can be reflected in P300 amplitude changes over time, as well as trajectories describing acquisition of postural control when compared in offspring from families with multiple cases of alcoholism or those with none or few, suggest that brain development provides a clue to why some individuals are more susceptible to becoming alcoholic. Finally, differences seen in amygdala volume between high- and low-risk adolescents suggest that functional differences seen in electrophysiological responding or neuropsychological test performance may have anatomical correlates.

Changes in P300 amplitude during an active standard auditory oddball task

This study evaluated whether P300 amplitude declines in response to repeated presentation of the target in a standard auditory oddball task; to what extent the decrease is affected by the number of targets presented, interrupted by an interblock interval (IBI, 3 min) and consistent. We also aimed to identify factors inducing P300 amplitude decrease and its psychological significance. Two blocks of 500 tonnes (each divided into five subblocks of 100 tones) were presented. First block: P300 amplitude was smaller in the first subblock than in the second, which we attribute to processing resources during the first subblock being divided between the task of identifying the target and the process of estimating subjective probability. Amplitude decreased from the second subblock onwards. The interblock interval was sufficient for amplitude to return to pre-decrease levels. The intrablock decline was replicated in the second block. The decline in P300 amplitude might to reflect a progressive automation of the context-updating operations.

P300 from inspiratory occlusion reflects orienting but not startle

Sudden onset inspiratory occlusion stimuli elicit large amplitude P300 components and also startle blinks. The primary purpose of this study was to assess the influence of the startle reflex on the respiratory related P300. A secondary purpose was to assess changes in P300 scalp topography as a function of stimulus familiarity. Young adults ( n=12) were exposed to 200 inspiratory occlusion stimuli, and EEG was recorded from 29 A1/A2 referenced sites. Data from the occlusions were divided into four consecutive blocks of 50 trials to assess blink and P300 habituation effects. Results showed that 40% of the occlusion stimuli elicited a blink response, and that blink amplitude showed significant habituation across the experimental session. Change in P300 amplitude across the experimental session varied according to scalp site. At central and parietal locations, P300 amplitude showed an initial decrease but then remained stable. Frontally, P300 amplitude decreased over each of the four trial blocks. P300 scalp topography showed a classic centro-parietal maximum, however, a more frontally orientated scalp focus was seen for the first trial block. P300 was not significantly different when derived from averages of responses containing and not containing blinks. These data indicate that the previously studied centro-parietal P300 is not related to a startle reflex. However, when occlusions are first presented, a scalp topography similar to that previously noted for novel stimuli is observed.

Neurodevelopmental patterns of visual P3b in association with familial risk for alcohol dependence and childhood diagnosis

Background: The P3b component of the event-related potential (ERP) has frequently been reported to be reduced in children and adolescents at high risk for developing alcoholism relative to control children and adolescents without familial loading for alcohol dependence. P300 amplitude changes during development for all children. Previously it has been shown that high-risk offspring display a pattern in which the amplitude is lower at age 8 with a smaller rate of change during adolescence. Methods: Admixture analysis was applied to data obtained for those children and adolescents having five or more annual assessments of ERPs to determine if multiple P3b growth patterns exist. The P3b amplitude patterns obtained were related to risk status, concurrent presence of childhood psychopathology (internalizing or externalizing), and age of onset to develop a diagnosis. Results: A pattern characterized by lower P3b amplitude at study entry and a slower rate of change during child and adolescent development (pattern 3) was most often associated with high-risk status in boys and high-risk status in combination with the presence of a childhood diagnosis in girls. Pattern 3 was significantly related to the overall presence of childhood psychopathology (internalizing or externalizing) and to the presence of an Axis I diagnosis at young adult follow-up. Conclusions: The developmental pattern previously described for offspring at high risk for developing alcoholism because of their familial/genetic background was confirmed. Admixture analysis has refined this observation and suggests that among all children and adolescents tested, three developmental patterns can be identified, one of which is most often seen in association with male high-risk children and adolescents.