Event-related Brain Potentials (event-related + brain_potential)

Distribution by Scientific Domains

Selected Abstracts

Neurocognitive variation in smoking behavior and withdrawal: genetic and affective moderators

D. E. Evans
A burgeoning literature suggests that attentional factors are associated with smoking behavior (e.g. direct nicotine effects and smoking withdrawal). This study examined differences in attentional processing between nonsmokers, satiated smokers and overnight nicotine-deprived smokers by comparing the amplitude of the P300 (P3) component of the event-related brain potential (ERP) elicited during a go,nogo task. We also examined the moderating effects of a common dopamine receptor genotype and state negative affect (SNA) on this ERP index of attention. Nonsmokers relative to smokers had greater nogo P3 amplitude. Carrying the A1 allele at the dopamine receptor D2 (DRD2) Taq1A polymorphism site moderated the effects of withdrawal on nogo P3 amplitude, suggesting the A1 allele is a vulnerability marker for withdrawal-related attentional deficits. Increased SNA also predicted attenuated P3 amplitude among deprived smokers. These findings suggest that DRD2 status and SNA moderate the effects of smoking status and withdrawal on neurocognitive variation during attentional processing. This research contributes to a better understanding of the role of individual differences and attentional processing in smoking behavior. [source]

The feedback correct-related positivity: Sensitivity of the event-related brain potential to unexpected positive feedback

Clay B. Holroyd
Abstract The N200 and the feedback error-related negativity (fERN) are two components of the event-related brain potential (ERP) that share similar scalp distributions, time courses, morphologies, and functional dependencies, which raises the question as to whether they are actually the same phenomenon. To investigate this issue, we recorded the ERP from participants engaged in two tasks that independently elicited the N200 and fERN. Our results indicate that they are, in fact, the same ERP component and further suggest that positive feedback elicits a positive-going deflection in the time range of the fERN. Taken together, these results indicate that negative feedback elicits a common N200 and that modulation of fERN amplitude results from the superposition on correct trials of a positive-going deflection that we term the feedback correct-related positivity. [source]

Error-related brain potentials are differentially related to awareness of response errors: Evidence from an antisaccade task

Sander Nieuwenhuis
The error negativity (Ne/ERN) and error positivity (Pe) are two components of the event-related brain potential (ERP) that are associated with action monitoring and error detection. To investigate the relation between error processing and conscious self-monitoring of behavior, the present experiment examined whether an Ne and Pe are observed after response errors of which participants are unaware. Ne and Pe measures, behavioral accuracy, and trial-to-trial subjective accuracy judgments were obtained from participants performing an antisaccade task, which elicits many unperceived, incorrect reflex-like saccades. Consistent with previous research, subjectively unperceived saccade errors were almost always immediately corrected, and were associated with faster correction times and smaller saccade sizes than perceived errors. Importantly, irrespective of whether the participant was aware of the error or not, erroneous saccades were followed by a sizable Ne. In contrast, the Pe was much more pronounced for perceived than for unperceived errors. Unperceived errors were characterized by the absence of posterror slowing. These and other results are consistent with the view that the Ne and Pe reflect the activity of two separate error monitoring processes, of which only the later process, reflected by the Pe, is associated with conscious error recognition and remedial action. [source]

Is there pre-attentive memory-based comparison of pitch?

Thomas Jacobsen
The brain's responsiveness to changes in sound frequency has been demonstrated by an overwhelming number of studies. Change detection occurs unintentionally and automatically. It is generally assumed that this brain response, the so-called mismatch negativity (MMN) of the event-related brain potential or evoked magnetic field, is based on the outcome of a memory-comparison mechanism rather than being due to a differential state of refractoriness of tonotopically organized cortical neurons. To the authors' knowledge, however, there is no entirely compelling evidence for this belief. An experimental protocol controlling for refractoriness effects was developed and a true memory-comparison-based brain response to pitch change was demonstrated. [source]

Auditory and speech processing and reading development in Chinese school children: behavioural and ERP evidence

DYSLEXIA, Issue 4 2005
Xiangzhi Meng
Abstract By measuring behavioural performance and event-related potentials (ERPs) this study investigated the extent to which Chinese school children's reading development is influenced by their skills in auditory, speech, and temporal processing. In Experiment 1, 102 normal school children's performance in pure tone temporal order judgment, tone frequency discrimination, temporal interval discrimination and composite tone pattern discrimination was measured. Results showed that children's auditory processing skills correlated significantly with their reading fluency, phonological awareness, word naming latency, and the number of Chinese characters learned. Regression analyses found that tone temporal order judgment, temporal interval discrimination and composite tone pattern discrimination could account for 32% of variance in phonological awareness. Controlling for the effect of phonological awareness, auditory processing measures still contributed significantly to variance in reading fluency and character naming. In Experiment 2, mismatch negativities (MMN) in event-related brain potentials were recorded from dyslexic children and the matched normal children, while these children listened passively to Chinese syllables and auditory stimuli composed of pure tones. The two groups of children did not differ in MMN to stimuli deviated in pure tone frequency and Chinese lexical tones. But dyslexic children showed smaller MMN to stimuli deviated in initial consonants or vowels of Chinese syllables and to stimuli deviated in temporal information of composite tone patterns. These results suggested that Chinese dyslexic children have deficits in auditory temporal processing as well as in linguistic processing and that auditory and temporal processing is possibly as important to reading development of children in a logographic writing system as in an alphabetic system. Copyright 2005 John Wiley & Sons, Ltd. [source]

A locus for an auditory processing deficit and language impairment in an extended pedigree maps to 12p13.31-q14.3

L. Addis
Despite the apparent robustness of language learning in humans, a large number of children still fail to develop appropriate language skills despite adequate means and opportunity. Most cases of language impairment have a complex etiology, with genetic and environmental influences. In contrast, we describe a three-generation German family who present with an apparently simple segregation of language impairment. Investigations of the family indicate auditory processing difficulties as a core deficit. Affected members performed poorly on a nonword repetition task and present with communication impairments. The brain activation pattern for syllable duration as measured by event-related brain potentials showed clear differences between affected family members and controls, with only affected members displaying a late discrimination negativity. In conjunction with psychoacoustic data showing deficiencies in auditory duration discrimination, the present results indicate increased processing demands in discriminating syllables of different duration. This, we argue, forms the cognitive basis of the observed language impairment in this family. Genome-wide linkage analysis showed a haplotype in the central region of chromosome 12 which reaches the maximum possible logarithm of odds ratio (LOD) score and fully co-segregates with the language impairment, consistent with an autosomal dominant, fully penetrant mode of inheritance. Whole genome analysis yielded no novel inherited copy number variants strengthening the case for a simple inheritance pattern. Several genes in this region of chromosome 12 which are potentially implicated in language impairment did not contain polymorphisms likely to be the causative mutation, which is as yet unknown. [source]

Cognitive processes facilitated by contextual cueing: Evidence from event-related brain potentials

Andrea Schankin
Abstract Finding a target in repeated search displays is faster than finding the same target in novel ones (contextual cueing). It is assumed that the visual context (the arrangement of the distracting objects) is used to guide attention efficiently to the target location. Alternatively, other factors, e.g., facilitation in early visual processing or in response selection, may play a role as well. In a contextual cueing experiment, participant's electrophysiological brain activity was recorded. Participants identified the target faster and more accurately in repeatedly presented displays. In this condition, the N2pc, a component reflecting the allocation of visual-spatial attention, was enhanced, indicating that attention was allocated more efficiently to those targets. However, also response-related processes, reflected by the LRP, were facilitated, indicating that guidance of attention cannot account for the entire contextual cueing benefit. [source]

Effects of intermodal attention on the auditory steady-state response and the event-related potential

Katja Saupe
Abstract The aim of the present study was to simultaneously measure and compare intermodal attention effects in event-related brain potentials (ERPs) and auditory steady-state responses (ASSRs). For this purpose, 40-Hz amplitude modulated tones and a visual fixation cross were presented concurrently. By means of target detection tasks either on the sounds or on the fixation cross, participants' attention was directed to the respective modality. Attended sounds elicited a negative difference (Nd) in the ERP relative to unattended sounds. Nd was divided into an early and a late part as often observed for intramodal attention. Moreover, attention to the sounds led to a significant enhancement of the ASSR. This modulation of the ASSR by intermodal attention is demonstrated for the first time in the EEG. The present data suggest that ASSRs could provide a useful tool for the investigation of the neural dynamics of intermodal attentional processes. [source]

What's special about personally familiar faces?

A multimodal approach
Abstract Dual-route models of face recognition suggest separate cognitive and affective routes. The predictions of these models were assessed in recognition tasks with unfamiliar, famous, and personally familiar faces. Whereas larger autonomic responses were only triggered for personally familiar faces, priming effects in reaction times to these faces, presumably reflecting cognitive recognition processes, were equal to those of famous faces. Activation of stored structural representations of familiar faces (face recognition units) was assessed by recording the N250r component in event-related brain potentials. Face recognition unit activation increased from unfamiliar over famous to personally familiar faces, suggesting that there are stronger representations for personally familiar than for famous faces. Because the topographies of the N250r for personally and famous faces were indistinguishable, a similar network of face recognition units can be assumed for both types of faces. [source]

Comparing arithmetic and semantic fact retrieval: Effects of problem size and sentence constraint on event-related brain potentials

Kerstin Jost
Abstract Event-related potentials were recorded with 61 electrodes from 16 students who verified either the correctness of single-digit multiplication problems or the semantic congruency of sentences. Multiplication problems varied in size and sentence fragments in constraint. Both semantic and arithmetic incongruencies evoked a typical N400 with a clear parieto-central maximum. In addition, numerically larger problems (87), in comparison to smaller problems (32), evoked a negativity starting at about 360 ms whose maximum was located over the right temporal-parietal scalp. These results indicate that the arithmetic incongruency and the problem-size effect are functionally distinct. It is suggested that the arithmetic and the semantic incongruency effects are both functionally related to a context-dependent spread of activation in specialized associative networks, whereas the arithmetic problem-size effect is due to rechecking routines that go beyond basic fact retrieval. [source]

Source memory for the color of pictures: Event-related brain potentials (ERPs) reveal sensory-specific retrieval-related activity

Yael M. Cycowicz
Abstract Remembering the context (i.e., source) in which an event occurred reveals episodic memory effects (EM) in the event-related brain potentials (ERP). In some verbal source memory experiments, a late prefrontal EM effect has been observed. In a different, pictorial source memory paradigm, a late, parieto-occipital EM effect was recorded. To assess whether these two EM effects stemmed from differences in task paradigms or from source-attribute differences, ERPs were recorded during source memory retrieval for object colors in two tasks. In the sequential task, old/new judgments were followed by source judgments (i.e., color). In the exclusion task, source memory judgments coincided with recognition judgments. For both tasks, late, parietao-occipital EM effects were observed. These findings suggest that it is not the nature of the task, but rather the perceptual characteristics of the source that lead to the presence of the parieto-occipital EM effect. The data further imply that memories for perceptual attributes such as color are stored in and retrieved from sensory-specific cortical areas. [source]

Representation of the standard: Stimulus context effects on the process generating the mismatch negativity component of event-related brain potentials

Elyse Sussman
Abstract In the auditory oddball paradigm, the frequent occurrence of a sound (the "standard") forms the basis of deviance detection. The incoming sounds are compared with the cortical representation of the standard and those sounds that do not match it elicit the mismatch negativity (MMN) event-related brain potential. Here we address the issue of whether the relative probability of the sounds in a sequence was a critical factor influencing which sounds would be represented as standards in the deviant comparison process. One frequent (F1) and two infrequent (D1 and D2) sounds that differed only in duration were presented in a sequence. D1 occurred proportionally as frequently with respect to D2 as F1 occurred with respect to D1. If the proportional relationship of sounds were critical then D1 could serve as a "standard" to D2 and thus D2 should elicit two MMNs. However, D2 elicited MMN only with respect to F1. This result as well as those obtained in two control conditions suggests that "standards" are not established on the basis of relative probability; they emerge as a result of global characteristics, the longer-term context, of the sound sequence. [source]