P3 Component (p3 + component)

Distribution by Scientific Domains


Selected Abstracts


Single-Nucleotide Polymorphisms in Corticotropin Releasing Hormone Receptor 1 Gene (CRHR1) Are Associated With Quantitative Trait of Event-Related Potential and Alcohol Dependence

ALCOHOLISM, Issue 6 2010
Andrew C. H. Chen
Background:, Endophenotypes reflect more proximal effects of genes than diagnostic categories, hence providing a more powerful strategy in searching for genes involved in complex psychiatric disorders. There is strong evidence suggesting the P3 amplitude of the event-related potential (ERP) as an endophenotype for the risk of alcoholism and other disinhibitory disorders. Recent studies demonstrated a crucial role of corticotropin releasing hormone receptor 1 (CRHR1) in the environmental stress response and ethanol self-administration in animal models. The aim of the present study was to test the potential associations between single-nucleotide polymorphisms (SNPs) in the CRHR1 gene and the quantitative trait, P3 amplitude during the processing of visual target signals in an oddball paradigm, as well as alcohol dependence diagnosis. Methods:, We analyzed a sample from the Collaborative Study on the Genetics of Alcoholism (COGA) comprising 1049 Caucasian subjects from 209 families (including 472 alcohol-dependent individuals). Quantitative transmission disequilibrium test (QTDT) and family-based association test (FBAT) were used to test the association, and false discovery rate (FDR) was applied to correct for multiple comparisons. Results:, Significant associations (p < 0.05) were found between the P3 amplitude and alcohol dependence with multiple SNPs in the CRHR1 gene. Conclusions:, Our results suggest that CRHR1 may be involved in modulating the P3 component of the ERP during information processing and in vulnerability to alcoholism. These findings underscore the utility of electrophysiology and the endophenotype approach in the genetic study of psychiatric disorders. [source]


Priming Deficiency in Male Subjects at Risk for Alcoholism: The N4 During a Lexical Decision Task

ALCOHOLISM, Issue 12 2009
Bangalore N. Roopesh
Background:, While there is extensive literature on the relationship between the P3 component of event-related potentials (ERPs) and risk for alcoholism, there are few published studies regarding other potentially important ERP components. One important candidate is the N4(00) component in the context of semantic processing, as abnormalities in this component have been reported for adult alcoholics. Method:, A semantic priming task was administered to nonalcohol dependent male offspring (18 to 25 years) of alcoholic fathers [high risk (HR) n = 23] and nonalcoholic fathers [low risk (LR) n = 28] to study whether the 2 groups differ in terms of the N4 component. Subjects were presented with 150 words and 150 nonwords. Among the words, 50 words (primed) were preceded by their antonyms (prime, n = 50), whereas the remaining 50 words were unprimed. For the analysis, N4 amplitude and latency as well as behavioral measures for the primed and unprimed words were considered. Results:, A significant interaction effect was observed between semantic condition and group, where HR subjects did not show N4 attenuation for primed stimuli. Conclusion:, The lack of N4 attenuation to primed stimuli and/or inability to differentiate between primed and unprimed stimuli, without latency and reaction time being affected, suggest deficits in semantic priming, especially in semantic expectancy and/or postlexical semantic processing in HR male offspring. Further, it indicates that it might be an electrophysiological endophenotype that reflects genetic vulnerability to develop alcoholism. [source]


Binge Drinking Affects Attentional and Visual Working Memory Processing in Young University Students

ALCOHOLISM, Issue 11 2009
Alberto Crego
Background:, Binge Drinking (BD) typically involves heavy drinking over a short time, followed by a period of abstinence, and is common among young people, especially university students. Animal studies have demonstrated that this type of alcohol consumption causes brain damage, especially in the nonmature brain. The aim of the present study was to determine how BD affects brain functioning in male and female university students, during the performance of a visual working memory task. Methods:, Event-related potentials (ERPs) were recorded, with an extensive set of 32 scalp electrodes, in 95 first-year university students (age range 18 to 20 years), comprising 42 binge drinkers (BD) and 53 controls, in a visual "identical pairs" continuous performance task. Principal components analysis was used to identify and analyze the N2 (negative waveform with a latency around 200 to 300 ms related to attentional processes) and P3 (positive waveform with a latency around 300 to 600 ms related to working memory processes) components of the ERPs. Results:, In the matching condition of the task, the N2 component in central and parietal regions was significantly larger in the BD than in the control group. In the control group, the P3 component was larger in the matching than in the nonmatching condition in the frontal, central, and parietal regions, whereas the BD group did not show any significant differences between conditions in any region. Conclusions:, The results of this study confirm the presence of electrophysiological differences between young university student binge drinkers and controls during the execution of a visual task with a high working memory load. The larger N2 in the BD group suggests higher levels of attentional effort required by this group to perform the task adequately. The absence of any differences in the P3 component in the different conditions (matching and nonmatching stimuli) in the BD group suggests a deficiency in the electrophysiological differentiation between relevant and irrelevant information, which may reflect some impairment of working memory processes. [source]


Intramodal and crossmodal processing delays in the attentional blink paradigm revealed by event-related potentials

PSYCHOPHYSIOLOGY, Issue 5 2008
Alexia Ptito
Abstract In the attentional blink (AB), processing of a second target (T2) is impaired if it is presented shortly after the onset of a first target (T1), leading to a decrease in accurate report of T2 if T2 is masked. Some prominent theories of the AB suggest that an amodal bottleneck in working memory consolidation underlies the AB. We investigated this by factorially manipulating T1 and T2 modalities (visual or auditory) using equivalent stimuli and tasks in both modalities to minimize task switching. T2 was not masked. In all modality combinations, the electrophysiological P3 component to T2, obtained by subtracting T1 only trials from T1+T2 trials, was delayed and reduced in amplitude when T2 was presented soon after T1 relative to when T1 and T2 were presented farther apart. Results provide support for a common amodal bottleneck that underlies the AB effects observed in all visual/auditory modality combinations. [source]


The effect of stimulus probability on P3 in the respiratory-related evoked potential

PSYCHOPHYSIOLOGY, Issue 1 2002
Kate E. Webster
The present study investigated the effect of target stimulus probability on the P3 component of the respiratory-related evoked potential (RREP). A single respiratory stimulus paradigm was employed where normal breaths served as standard stimuli and occluded breaths presented at various probability levels served as target stimuli. EEG was recorded from 29 channels in young adults in two conditions. In Condition 1, occlusions were presented at target probabilities of 0.5, 0.33, 0.25, 0.2, 0.1, and 0.05, that is, every 2nd, 3rd, 4th, 5th, 10th, and 20th breath. Order of target probability presentation varied randomly. Condition 2 used the same target probabilities, but held breathing rate constant by using a paced respiration task. Results indicated that P3 amplitude was significantly affected by stimulus probability, such that the component showed an inverse relationship with probability. This effect was similar between conditions. However, P3 amplitude reduced and latency increased when the secondary task of paced respiration was introduced. These data suggest that models developed to describe the effect of stimulus probability on the amplitude of visual and auditory P3 components are applicable to the respiratory somatosensory modality. [source]


Delayed visual P3 in unilateral thalamic stroke

EUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2000
E. Trinka
The P3 potential is accepted as a neurophysiological correlate of memory and attention. Delayed latencies were reported in different forms of dementias. Although the generator sites are still under debate, the thalamus may play a crucial role. The aim of this study was to investigate the influence of an unilateral thalamic ischaemic infarction on P3 generation. The event-related P3 component of six patients (2 male, four female; mean age 47 years, range 22,63 years) with unilateral thalamic ischaemic infarction was studied and compared to age-matched controls (five male, nine female; mean age 45.8 years; range 22,69 years). All patients underwent full clinical examination, CCT, and MRI scan. P3 potentials were recorded with a visual three stimulus discrimination paradigm. The mean P3 latency of the patient group to the target stimulus was delayed (469.7 ms, SD = 36.8) compared with the controls (378.8 ms, SD = 51.5; P < 0.05). The mean P3 latency to the unexpected stimulus was delayed in patients with thalamic infarction compared with controls [477 ms (SD = 46.6) vs. 381.2 ms (SD = 48.5); P < 0.001). Delayed P3 components of the event-related potential (ERP) were recorded in six patients with unilateral thalamic infarction, suggesting an important role of the thalamus in the generation of the P3 potential. [source]


Gender differences in behavioral inhibitory control: ERP evidence from a two-choice oddball task

PSYCHOPHYSIOLOGY, Issue 6 2008
Jiajin Yuan
Abstract The inhibition of inappropriate behaviors is important for adaptive living in changing environments. The present study investigated gender-related behavioral inhibitory control by recording event-related potentials for standard and deviant stimuli while subjects performed a standard/deviant distinction task by accurately pressing different keys within 1000 ms. The results showed faster reaction times (RTs) for deviant stimuli in women than in men, although RTs for standard stimuli were similar across genders. There were significant gender and stimulus interaction effects on mean amplitudes during each of the 170,230-ms, 250,330-ms, and 350,600-ms intervals, and women exhibited shorter latencies and larger amplitudes than men at deviant-related P2, N2, and P3 components. As an accurate, fast response to the rare deviant stimuli involves behavioral inhibitory control on the prepotent response whereas the response to the standard stimuli does not, it is clear that there is a general gender difference in behavioral control for human adults. This may relate to differential inhibitory demands by each gender during evolution. [source]


The effect of stimulus probability on P3 in the respiratory-related evoked potential

PSYCHOPHYSIOLOGY, Issue 1 2002
Kate E. Webster
The present study investigated the effect of target stimulus probability on the P3 component of the respiratory-related evoked potential (RREP). A single respiratory stimulus paradigm was employed where normal breaths served as standard stimuli and occluded breaths presented at various probability levels served as target stimuli. EEG was recorded from 29 channels in young adults in two conditions. In Condition 1, occlusions were presented at target probabilities of 0.5, 0.33, 0.25, 0.2, 0.1, and 0.05, that is, every 2nd, 3rd, 4th, 5th, 10th, and 20th breath. Order of target probability presentation varied randomly. Condition 2 used the same target probabilities, but held breathing rate constant by using a paced respiration task. Results indicated that P3 amplitude was significantly affected by stimulus probability, such that the component showed an inverse relationship with probability. This effect was similar between conditions. However, P3 amplitude reduced and latency increased when the secondary task of paced respiration was introduced. These data suggest that models developed to describe the effect of stimulus probability on the amplitude of visual and auditory P3 components are applicable to the respiratory somatosensory modality. [source]


The role of docosahexaenoic acid on visual evoked potentials in one kidney-one clip hypertension

ACTA OPHTHALMOLOGICA, Issue 4 2006
Gulay Hacioglu
Abstract. Purpose:, To investigate the effects of polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) on visual evoked potentials (VEPs) in a one kidney-one clip (1K-1C) hypertension model in rats. Methods:, Five experimental groups were formed: a control group, a sham group, a group supplemented with DHA, a 1K-1C group, and a 1K-1C + DHA group. The DHA groups were treated for 60 days. In the 1K-1C groups, the right kidney was removed and a silver clip with a 0.2-mm gap was placed on the left renal artery. Results:, The DHA-supplemented rats had lower blood pressure than their respective controls (p < 0.01). The increased brain and retina thiobarbituric acid reactive substances (TBARS) levels in hypertensive rats were abolished by DHA administration. The brain nitrite levels were lower in the DHA, 1K-1C and 1K-1C + DHA groups compared with the control group (p < 0.01), and the retina nitrite level was higher in the 1K-1C + DHA group compared with the DHA and 1K-1C groups (p < 0.01). There was an improvement of P2, N2 and P3 components following DHA supplementation in 1K-1C hypertensive rats compared with the 1K-1C group. Conclusion:, The present study suggests that DHA supplementation has the potential to prevent VEP changes caused by an experimental model of hypertension. This state might be related to the lipid peroxidation lowering effect of DHA. [source]