sLORETA current source density analysis of evoked potentials for spatial updating in a virtual navigation task

PubMed Central

Nguyen, Hai M.; Matsumoto, Jumpei; Tran, Anh H.; Ono, Taketoshi; Nishijo, Hisao

2014-01-01

Previous studies have reported that multiple brain regions are activated during spatial navigation. However, it is unclear whether these activated brain regions are specifically associated with spatial updating or whether some regions are recruited for parallel cognitive processes. The present study aimed to localize current sources of event related potentials (ERPs) associated with spatial updating specifically. In the control phase of the experiment, electroencephalograms (EEGs) were recorded while subjects sequentially traced 10 blue checkpoints on the streets of a virtual town, which were sequentially connected by a green line, by manipulating a joystick. In the test phase of the experiment, the checkpoints and green line were not indicated. Instead, a tone was presented when the subjects entered the reference points where they were then required to trace the 10 invisible spatial reference points corresponding to the checkpoints. The vertex-positive ERPs with latencies of approximately 340 ms from the moment when the subjects entered the unmarked reference points were significantly larger in the test than in the control phases. Current source density analysis of the ERPs by standardized low-resolution brain electromagnetic tomography (sLORETA) indicated activation of brain regions in the test phase that are associated with place and landmark recognition (entorhinal cortex/hippocampus, parahippocampal and retrosplenial cortices, fusiform, and lingual gyri), detecting self-motion (posterior cingulate and posterior insular cortices), motor planning (superior frontal gyrus, including the medial frontal cortex), and regions that process spatial attention (inferior parietal lobule). The present results provide the first identification of the current sources of ERPs associated with spatial updating, and suggest that multiple systems are active in parallel during spatial updating. PMID:24624067

Post-repolarization refractoriness increases vulnerability to block and initiation of reentrant impulses in heterogeneous infarcted myocardium.

PubMed

Cabo, Candido

2015-10-01

Myocardial infarction causes remodeling of the tissue structure and the density and kinetics of several ion channels in the cell membrane. Heterogeneities in refractory period (ERP) have been shown to occur in the infarct border zone and have been proposed to lead to initiation of arrhythmias. The purpose of this study is to quantify the window of vulnerability (WV) to block and initiation of reentrant impulses in myocardium with ERP heterogeneities using computer simulations. We found that ERP transitions at the border between normal ventricular cells (NZ) with different ERPs are smooth, whereas ERP transitions between NZ and infarct border zone cells (IZ) are abrupt. The profile of the ERP transitions is a combination of electrotonic interaction between NZ and IZ cells and the characteristic post-repolarization refractoriness (PRR) of IZ cells. ERP heterogeneities between NZ and IZ cells are more vulnerable to block and initiation of reentrant impulses than ERP heterogeneities between NZ cells. The relationship between coupling intervals of premature impulses (V1V2) and coupling intervals between premature and first reentrant impulses (V2T1) at NZ/NZ and NZ/IZ borders is inverse (i.e. the longer the coupling intervals of premature impulses the shorter the coupling interval between the premature and first reentrant impulses); this is in contrast with the reported V1V2/V2T1 relationship measured during initiation of reentrant impulses in canine infarcted hearts which is direct. (1) ERP transitions at the NZ-IZ border are abrupt as a consequence of PRR; (2) PRR increases the vulnerability to block and initiation of reentrant impulses in heterogeneous myocardium; (3) V1V2/V2T1 relationships measured at ERP heterogeneities in the computer model and in experimental canine infarcts are not consistent. Therefore, it is likely that other mechanisms like micro and/or macro structural heterogeneities also contribute to initiation of reentrant impulses in infarcted hearts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cognitive MMN and P300 in mild cognitive impairment and Alzheimer's disease: A high density EEG-3D vector field tomography approach.

PubMed

Papadaniil, Chrysa D; Kosmidou, Vasiliki E; Tsolaki, Anthoula; Tsolaki, Magda; Kompatsiaris, Ioannis Yiannis; Hadjileontiadis, Leontios J

2016-10-01

Precise preclinical detection of dementia for effective treatment and stage monitoring is of great importance. Miscellaneous types of biomarkers, e.g., biochemical, genetic, neuroimaging, and physiological, have been proposed to diagnose Alzheimer's disease (AD), the usual suspect behind manifested cognitive decline, and mild cognitive impairment (MCI), a neuropathology prior to AD that does not affect cognitive functions. Event related potential (ERP) methods constitute a non-invasive, inexpensive means of analysis and have been proposed as sensitive biomarkers of cognitive impairment; besides, various ERP components are strongly linked with working memory, attention, sensory processing and motor responses. In this study, an auditory oddball task is employed, to acquire high density electroencephalograhy recordings from healthy elderly controls, MCI and AD patients. The mismatch negativity (MMN) and P300 ERP components are then extracted and their relationship with neurodegeneration is examined. Then, the neural activation at these components is reconstructed using the 3D vector field tomography (3D-VFT) inverse solution. The results reveal a decline of both ERPs amplitude, and a statistically significant prolongation of their latency as cognitive impairment advances. For the MMN, higher brain activation is usually localized in the inferior frontal and superior temporal gyri in the controls. However, in AD, parietal sites exhibit strong activity. Stronger P300 generators are mostly found in the frontal lobe for the controls, but in AD they often shift to the temporal lobe. Reduction in inferior frontal source strength and the switch of the maximum intensity area to parietal and superior temporal sites suggest that these areas, especially the former, are of particular significance when neurodegenerative disorders are investigated. The modulation of MMN and P300 can serve to produce biomarkers of dementia and its progression, and brain imaging can further contribute to the diagnostic efficiency of ERPs. Copyright © 2016. Published by Elsevier B.V.

The Neural Basis of Insight Problem Solving: An Event-Related Potential Study

ERIC Educational Resources Information Center

Qiu, Jiang; Li, Hong; Yang, Dong; Luo, Yuejia; Li, Ying; Wu, Zhenzhen; Zhang, Qinglin

2008-01-01

The electrophysiological correlates of successful insight problem solving (Chinese logogriphs) were studied in 18 healthy subjects using high-density event-related potentials (ERPs). A new experimental paradigm (learning-testing model) was adopted in order to make subjects find a solution on their own initiative rather than receive an answer…

Spatiotemporal neural dynamics of moral judgment: A high-density ERP study

PubMed Central

Yoder, Keith J.

2014-01-01

Morality is a pervasive aspect of human nature across all cultures, and neuroscience investigations are necessary for identifying what computational mechanisms underpin moral cognition. The current study used high-density ERPs to examine how moral evaluations are mediated by automatic and controlled processes as well as how quickly information and causal-intentional representations can be extracted when viewing morally laden behavior. The study also explored the extent to which individual dispositions in affective and cognitive empathy as well as justice sensitivity influence the encoding of moral valence when healthy participants make moral judgments about prosocial (interpersonal assistance) and antisocial (interpersonal harm) actions. Moral judgment differences were reflected in differential amplitudes for components associated with cognitive appraisal (LPP) as well as early components associated with emotional salience (N1 and N2). Moreover, source estimation was performed to indicate potential neural generators. A posterior-to-anterior shift was observed, with current density peaks first in right inferior parietal cortex (at the temporoparietal junction), then later in medial prefrontal cortex. Cognitive empathy scores predicted behavioral ratings of blame as well as differential amplitudes in LPP and component activity at posterior sites. Overall, this study offers important insights into the temporal unfolding of moral evaluations, including when in time individual differences in empathy influence neural encoding of moral valence. PMID:24905282

Configurations and implementation of payroll system using open source erp: a case study of Koperasi PT Sri

NASA Astrophysics Data System (ADS)

Terminanto, A.; Swantoro, H. A.; Hidayanto, A. N.

2017-12-01

Enterprise Resource Planning (ERP) is an integrated information system to manage business processes of companies of various business scales. Because of the high cost of ERP investment, ERP implementation is usually done in large-scale enterprises, Due to the complexity of implementation problems, the success rate of ERP implementation is still low. Open Source System ERP becomes an alternative choice of ERP application to SME companies in terms of cost and customization. This study aims to identify characteristics and configure the implementation of OSS ERP Payroll module in KKPS (Employee Cooperative PT SRI) using OSS ERP Odoo and using ASAP method. This study is classified into case study research and action research. Implementation of OSS ERP Payroll module is done because the HR section of KKPS has not been integrated with other parts. The results of this study are the characteristics and configuration of OSS ERP payroll module in KKPS.

Self-Referential Processing in Depressed Adolescents: A High-Density ERP Study

PubMed Central

Auerbach, Randy P.; Stanton, Colin H.; Proudfit, Greg Hajcak; Pizzagalli, Diego A.

2015-01-01

Despite the alarming increase in the prevalence of depression during adolescence, particularly among female adolescents, the pathophysiology of depression in adolescents remains largely unknown. Event-related potentials (ERPs) provide an ideal approach to investigate cognitive-affective processes associated with depression in adolescents, especially in the context of negative self-referential processing biases. In this study, healthy (n = 30) and depressed (n = 22) female adolescents completed a self-referential encoding task while ERP data were recorded. To examine cognitive-affective processes associated with self-referential processing, P1, P2, and late positive potential (LPP) responses to negative and positive words were investigated, and intracortical sources of scalp effects were probed using Low Resolution Electromagnetic Tomography (LORETA). Additionally, we tested whether key cognitive processes (e.g., maladaptive self-view, self-criticism) previously implicated in depression related to ERP components. Relative to healthy female subjects, depressed females endorsed more negative and fewer positive words, and free recalled and recognized fewer positive words. With respect to ERPs, compared to healthy female adolescents, depressed adolescents exhibited greater P1 amplitudes following negative words, which was associated with a more maladaptive self-view and self-criticism. In both early and late LPP responses, depressed females showed greater activity following negative versus positive words, whereas healthy females demonstrated the opposite pattern. For both P1 and LPP, LORETA revealed reduced inferior frontal gyrus activity in response to negative words in depressed versus healthy female adolescents. Collectively, these findings suggest that the P1 and LPP reflect biased self-referential processing in female adolescents with depression. Potential treatment implications are discussed. PMID:25643205

Critical challenges in ERP implementation: A qualitative case study in the Canadian oil and gas industry

NASA Astrophysics Data System (ADS)

Menon, Sreekumar A.

This exploratory qualitative single-case study examines critical challenges encountered during ERP implementation based on individual perspectives in four project roles: senior leaders, project managers, project team members, and business users, all specifically in Canadian oil and gas industry. Data was collected by interviewing participants belonging to these categories, and by analyzing project documentation about ERP implementation. The organization for the case study was a leading multinational oil and gas company having a substantial presence in the energy sector in Canada. The study results were aligned with the six management questions regarding critical challenges in ERP: (a) circumstances to implement ERP, (b) benefits and process improvements achieved, (c) best practices implemented, (d) critical challenges encountered, (e) strategies and mitigating actions used, and (f) recommendations to improve future ERP implementations. The study results highlight six key findings. First, the study provided valid circumstances for implementing ERP systems. Second, the study underscored the importance of benefits and process improvements in ERP implementation. Third, the study highlighted that adoption of best practices is crucial for ERP Implementation. Fourth, the study found that critical challenges are encountered in ERP Implementation and are significant during ERP implementation. Fifth, the study found that strategies and mitigating actions can overcome challenges in ERP implementation. Finally, the study provided ten major recommendations on how to improve future ERP implementations.

Combined ERP/fMRI evidence for early word recognition effects in the posterior inferior temporal gyrus.

PubMed

Dien, Joseph; Brian, Eric S; Molfese, Dennis L; Gold, Brian T

2013-10-01

Two brain regions with established roles in reading are the posterior middle temporal gyrus and the posterior fusiform gyrus (FG). Lesion studies have also suggested that the region located between them, the posterior inferior temporal gyrus (pITG), plays a central role in word recognition. However, these lesion results could reflect disconnection effects since neuroimaging studies have not reported consistent lexicality effects in pITG. Here we tested whether these reported pITG lesion effects are due to disconnection effects or not using parallel Event-related Potentials (ERP)/functional magnetic resonance imaging (fMRI) studies. We predicted that the Recognition Potential (RP), a left-lateralized ERP negativity that peaks at about 200-250 msec, might be the electrophysiological correlate of pITG activity and that conditions that evoke the RP (perceptual degradation) might therefore also evoke pITG activity. In Experiment 1, twenty-three participants performed a lexical decision task (temporally flanked by supraliminal masks) while having high-density 129-channel ERP data collected. In Experiment 2, a separate group of fifteen participants underwent the same task while having fMRI data collected in a 3T scanner. Examination of the ERP data suggested that a canonical RP effect was produced. The strongest corresponding effect in the fMRI data was in the vicinity of the pITG. In addition, results indicated stimulus-dependent functional connectivity between pITG and a region of the posterior FG near the Visual Word Form Area (VWFA) during word compared to nonword processing. These results provide convergent spatiotemporal evidence that the pITG contributes to early lexical access through interaction with the VWFA. Copyright © 2013 Elsevier Ltd. All rights reserved.

Is the Surface Potential Integral of a Dipole in a Volume Conductor Always Zero? A Cloud Over the Average Reference of EEG and ERP.

PubMed

Yao, Dezhong

2017-03-01

Currently, average reference is one of the most widely adopted references in EEG and ERP studies. The theoretical assumption is the surface potential integral of a volume conductor being zero, thus the average of scalp potential recordings might be an approximation of the theoretically desired zero reference. However, such a zero integral assumption has been proved only for a spherical surface. In this short communication, three counter-examples are given to show that the potential integral over the surface of a dipole in a volume conductor may not be zero. It depends on the shape of the conductor and the orientation of the dipole. This fact on one side means that average reference is not a theoretical 'gold standard' reference, and on the other side reminds us that the practical accuracy of average reference is not only determined by the well-known electrode array density and its coverage but also intrinsically by the head shape. It means that reference selection still is a fundamental problem to be fixed in various EEG and ERP studies.

An event-related potential study of deception to self preferences.

PubMed

Tu, Shen; Li, Hong; Jou, Jerwen; Zhang, Qinglin; Wang, Ting; Yu, Caiyun; Qiu, Jiang

2009-01-09

The spatiotemporal analysis of brain activation during the execution of deceptive decision-making was performed in 14 normal young adult subjects by using high-density event-related brain potentials (ERPs) with a delayed-response paradigm (subjects were required to hide their true attitudes for a moment). Our results showed that between 400 and 700 ms after stimulus onset, Deceptive items elicited a more negative ERP deflection (N400-700) than Truthful items, and between 1000 and 2000 ms, Deceptive items elicited a more positive ERP deflection (P1000-2000) than Truthful items. Analyses using dipole locations indicated that: (1) the generators of N400-700 were localized in the medial frontal gyrus (GFM) and middle temporal gyrus (GTM), which might be involved in conflict detection and control during deceptive decision-making; and (2) the generators of P1000-2000 were localized near the cuneus (CU) and the cingulate gyrus, which might be involved in conflict coordination in working memory due to deception.

An Investigation of the Relationship Between fMRI and ERP Source Localized Measurements of Brain Activity during Face Processing

PubMed Central

Richards, Todd; Webb, Sara Jane; Murias, Michael; Merkle, Kristen; Kleinhans, Natalia M.; Johnson, L. Clark; Poliakov, Andrew; Aylward, Elizabeth; Dawson, Geraldine

2013-01-01

Brain activity patterns during face processing have been extensively explored with functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs). ERP source localization adds a spatial dimension to the ERP time series recordings, which allows for a more direct comparison and integration with fMRI findings. The goals for this study were (1) to compare the spatial descriptions of neuronal activity during face processing obtained with fMRI and ERP source localization using low-resolution electro-magnetic tomography (LORETA), and (2) to use the combined information from source localization and fMRI to explore how the temporal sequence of brain activity during face processing is summarized in fMRI activation maps. fMRI and high-density ERP data were acquired in separate sessions for 17 healthy adult males for a face and object processing task. LORETA statistical maps for the comparison of viewing faces and viewing houses were coregistered and compared to fMRI statistical maps for the same conditions. The spatial locations of face processing-sensitive activity measured by fMRI and LORETA were found to overlap in a number of areas including the bilateral fusiform gyri, the right superior, middle and inferior temporal gyri, and the bilateral precuneus. Both the fMRI and LORETA solutions additionally demon-strated activity in regions that did not overlap. fMRI and LORETA statistical maps of face processing-sensitive brain activity were found to converge spatially primarily at LORETA solution latencies that were within 18 ms of the N170 latency. The combination of data from these techniques suggested that electrical brain activity at the latency of the N170 is highly represented in fMRI statistical maps. PMID:19322649

Electrical Neuroimaging of Music Processing Reveals Mid-Latency Changes with Level of Musical Expertise

PubMed Central

James, Clara E.; Oechslin, Mathias S.; Michel, Christoph M.; De Pretto, Michael

2017-01-01

This original research focused on the effect of musical training intensity on cerebral and behavioral processing of complex music using high-density event-related potential (ERP) approaches. Recently we have been able to show progressive changes with training in gray and white matter, and higher order brain functioning using (f)MRI [(functional) Magnetic Resonance Imaging], as well as changes in musical and general cognitive functioning. The current study investigated the same population of non-musicians, amateur pianists and expert pianists using spatio-temporal ERP analysis, by means of microstate analysis, and ERP source imaging. The stimuli consisted of complex musical compositions containing three levels of transgression of musical syntax at closure that participants appraised. ERP waveforms, microstates and underlying brain sources revealed gradual differences according to musical expertise in a 300–500 ms window after the onset of the terminal chords of the pieces. Within this time-window, processing seemed to concern context-based memory updating, indicated by a P3b-like component or microstate for which underlying sources were localized in the right middle temporal gyrus, anterior cingulate and right parahippocampal areas. Given that the 3 expertise groups were carefully matched for demographic factors, these results provide evidence of the progressive impact of training on brain and behavior. PMID:29163017

Electrical Neuroimaging of Music Processing Reveals Mid-Latency Changes with Level of Musical Expertise.

PubMed

James, Clara E; Oechslin, Mathias S; Michel, Christoph M; De Pretto, Michael

2017-01-01

This original research focused on the effect of musical training intensity on cerebral and behavioral processing of complex music using high-density event-related potential (ERP) approaches. Recently we have been able to show progressive changes with training in gray and white matter, and higher order brain functioning using (f)MRI [(functional) Magnetic Resonance Imaging], as well as changes in musical and general cognitive functioning. The current study investigated the same population of non-musicians, amateur pianists and expert pianists using spatio-temporal ERP analysis, by means of microstate analysis, and ERP source imaging. The stimuli consisted of complex musical compositions containing three levels of transgression of musical syntax at closure that participants appraised. ERP waveforms, microstates and underlying brain sources revealed gradual differences according to musical expertise in a 300-500 ms window after the onset of the terminal chords of the pieces. Within this time-window, processing seemed to concern context-based memory updating, indicated by a P3b-like component or microstate for which underlying sources were localized in the right middle temporal gyrus, anterior cingulate and right parahippocampal areas. Given that the 3 expertise groups were carefully matched for demographic factors, these results provide evidence of the progressive impact of training on brain and behavior.

The infant mirror neuron system studied with high density EEG.

PubMed

Nyström, Pär

2008-01-01

The mirror neuron system has been suggested to play a role in many social capabilities such as action understanding, imitation, language and empathy. These are all capabilities that develop during infancy and childhood, but the human mirror neuron system has been poorly studied using neurophysiological measures. This study measured the brain activity of 6-month-old infants and adults using a high-density EEG net with the aim of identifying mirror neuron activity. The subjects viewed both goal-directed movements and non-goal-directed movements. An independent component analysis was used to extract the sources of cognitive processes. The desynchronization of the mu rhythm in adults has been shown to be a marker for activation of the mirror neuron system and was used as a criterion to categorize independent components between subjects. The results showed significant mu desynchronization in the adult group and significantly higher ERP activation in both adults and 6-month-olds for the goal-directed action observation condition. This study demonstrate that infants as young as 6 months display mirror neuron activity and is the first to present a direct ERP measure of the mirror neuron system in infants.

The effects of semantic congruency: a research of audiovisual P300-speller.

PubMed

Cao, Yong; An, Xingwei; Ke, Yufeng; Jiang, Jin; Yang, Hanjun; Chen, Yuqian; Jiao, Xuejun; Qi, Hongzhi; Ming, Dong

2017-07-25

Over the past few decades, there have been many studies of aspects of brain-computer interface (BCI). Of particular interests are event-related potential (ERP)-based BCI spellers that aim at helping mental typewriting. Nowadays, audiovisual unimodal stimuli based BCI systems have attracted much attention from researchers, and most of the existing studies of audiovisual BCIs were based on semantic incongruent stimuli paradigm. However, no related studies had reported that whether there is difference of system performance or participant comfort between BCI based on semantic congruent paradigm and that based on semantic incongruent paradigm. The goal of this study was to investigate the effects of semantic congruency in system performance and participant comfort in audiovisual BCI. Two audiovisual paradigms (semantic congruent and incongruent) were adopted, and 11 healthy subjects participated in the experiment. High-density electrical mapping of ERPs and behavioral data were measured for the two stimuli paradigms. The behavioral data indicated no significant difference between congruent and incongruent paradigms for offline classification accuracy. Nevertheless, eight of the 11 participants reported their priority to semantic congruent experiment, two reported no difference between the two conditions, and only one preferred the semantic incongruent paradigm. Besides, the result indicted that higher amplitude of ERP was found in incongruent stimuli based paradigm. In a word, semantic congruent paradigm had a better participant comfort, and maintained the same recognition rate as incongruent paradigm. Furthermore, our study suggested that the paradigm design of spellers must take both system performance and user experience into consideration rather than merely pursuing a larger ERP response.

ERP correlates of word production predictors in picture naming: a trial by trial multiple regression analysis from stimulus onset to response.

PubMed

Valente, Andrea; Bürki, Audrey; Laganaro, Marina

2014-01-01

A major effort in cognitive neuroscience of language is to define the temporal and spatial characteristics of the core cognitive processes involved in word production. One approach consists in studying the effects of linguistic and pre-linguistic variables in picture naming tasks. So far, studies have analyzed event-related potentials (ERPs) during word production by examining one or two variables with factorial designs. Here we extended this approach by investigating simultaneously the effects of multiple theoretical relevant predictors in a picture naming task. High density EEG was recorded on 31 participants during overt naming of 100 pictures. ERPs were extracted on a trial by trial basis from picture onset to 100 ms before the onset of articulation. Mixed-effects regression models were conducted to examine which variables affected production latencies and the duration of periods of stable electrophysiological patterns (topographic maps). Results revealed an effect of a pre-linguistic variable, visual complexity, on an early period of stable electric field at scalp, from 140 to 180 ms after picture presentation, a result consistent with the proposal that this time period is associated with visual object recognition processes. Three other variables, word Age of Acquisition, Name Agreement, and Image Agreement influenced response latencies and modulated ERPs from ~380 ms to the end of the analyzed period. These results demonstrate that a topographic analysis fitted into the single trial ERPs and covering the entire processing period allows one to associate the cost generated by psycholinguistic variables to the duration of specific stable electrophysiological processes and to pinpoint the precise time-course of multiple word production predictors at once.

Neurocognitive Deficits in Male Alcoholics: An ERP/sLORETA Analysis of the N2 Component in an Equal Probability Go/NoGo Task

PubMed Central

Pandey, AK; Kamarajan, C; Tang, Y; Chorlian, DB; Roopesh, BN; Manz, N; Stimus, A; Rangaswamy, M; Porjesz, B

2011-01-01

In alcoholism research, studies concerning time-locked electrophysiological aspects of response inhibition have concentrated mainly on the P3 component of the event-related potential (ERP). The objective of the present study was to investigate the N2 component of the ERP to elucidate possible brain dysfunction related to the motor response and its inhibition using a Go/NoGo task in alcoholics. The sample consisted of 78 abstinent alcoholic males and 58 healthy male controls. The N2 peak was compared across group and task conditions. Alcoholics showed significantly reduced N2 peak amplitudes compared to normal controls for Go as well as NoGo task conditions. Control subjects showed significantly larger NoGo than Go N2 amplitudes at frontal regions, whereas alcoholics did not show any differences between task conditions at frontal regions. Standardized Low Resolution Electromagnetic Tomography Analysis (sLORETA) indicated that alcoholics had significantly lower current density at the source than control subjects for the NoGo condition at bilateral anterior prefrontal regions, whereas the differences between groups during the Go trials was not statistically significant. Furthermore, NoGo current density across both groups revealed significantly more activation in bilateral anterior cingulate cortical (ACC) areas, with the maximum activation in the right cingulate regions. However, the magnitude of this difference was much less in alcoholics compared to control subjects. These findings suggest that alcoholics may have deficits in effortful processing during the motor response and its inhibition, suggestive of possible frontal lobe dysfunction. PMID:22024409

Towards a unified understanding of event-related changes in the EEG: the firefly model of synchronization through cross-frequency phase modulation.

PubMed

Burgess, Adrian P

2012-01-01

Although event-related potentials (ERPs) are widely used to study sensory, perceptual and cognitive processes, it remains unknown whether they are phase-locked signals superimposed upon the ongoing electroencephalogram (EEG) or result from phase-alignment of the EEG. Previous attempts to discriminate between these hypotheses have been unsuccessful but here a new test is presented based on the prediction that ERPs generated by phase-alignment will be associated with event-related changes in frequency whereas evoked-ERPs will not. Using empirical mode decomposition (EMD), which allows measurement of narrow-band changes in the EEG without predefining frequency bands, evidence was found for transient frequency slowing in recognition memory ERPs but not in simulated data derived from the evoked model. Furthermore, the timing of phase-alignment was frequency dependent with the earliest alignment occurring at high frequencies. Based on these findings, the Firefly model was developed, which proposes that both evoked and induced power changes derive from frequency-dependent phase-alignment of the ongoing EEG. Simulated data derived from the Firefly model provided a close match with empirical data and the model was able to account for i) the shape and timing of ERPs at different scalp sites, ii) the event-related desynchronization in alpha and synchronization in theta, and iii) changes in the power density spectrum from the pre-stimulus baseline to the post-stimulus period. The Firefly Model, therefore, provides not only a unifying account of event-related changes in the EEG but also a possible mechanism for cross-frequency information processing.

Towards a Unified Understanding of Event-Related Changes in the EEG: The Firefly Model of Synchronization through Cross-Frequency Phase Modulation

PubMed Central

Burgess, Adrian P.

2012-01-01

Although event-related potentials (ERPs) are widely used to study sensory, perceptual and cognitive processes, it remains unknown whether they are phase-locked signals superimposed upon the ongoing electroencephalogram (EEG) or result from phase-alignment of the EEG. Previous attempts to discriminate between these hypotheses have been unsuccessful but here a new test is presented based on the prediction that ERPs generated by phase-alignment will be associated with event-related changes in frequency whereas evoked-ERPs will not. Using empirical mode decomposition (EMD), which allows measurement of narrow-band changes in the EEG without predefining frequency bands, evidence was found for transient frequency slowing in recognition memory ERPs but not in simulated data derived from the evoked model. Furthermore, the timing of phase-alignment was frequency dependent with the earliest alignment occurring at high frequencies. Based on these findings, the Firefly model was developed, which proposes that both evoked and induced power changes derive from frequency-dependent phase-alignment of the ongoing EEG. Simulated data derived from the Firefly model provided a close match with empirical data and the model was able to account for i) the shape and timing of ERPs at different scalp sites, ii) the event-related desynchronization in alpha and synchronization in theta, and iii) changes in the power density spectrum from the pre-stimulus baseline to the post-stimulus period. The Firefly Model, therefore, provides not only a unifying account of event-related changes in the EEG but also a possible mechanism for cross-frequency information processing. PMID:23049827

Neuroelectrical signs of selective attention to color in boys with attention-deficit hyperactivity disorder.

PubMed

van der Stelt, O; van der Molen, M; Boudewijn Gunning, W; Kok, A

2001-10-01

In order to gain insight into the functional and macroanatomical loci of visual selective processing deficits that may be basic to attention-deficit hyperactivity disorder (ADHD), the present study examined multi-channel event-related potentials (ERPs) recorded from 7- to 11-year-old boys clinically diagnosed as having ADHD (n=24) and age-matched healthy control boys (n=24) while they performed a visual (color) selective attention task. The spatio-temporal dynamics of several ERP components related to attention to color were characterized using topographic profile analysis, topographic mapping of the ERP and associated scalp current density distributions, and spatio-temporal source potential modeling. Boys with ADHD showed a lower target hit rate, a higher false-alarm rate, and a lower perceptual sensitivity than controls. Also, whereas color attention induced in the ERPs from controls a characteristic early frontally maximal selection positivity (FSP), ADHD boys displayed little or no FSP. Similarly, ADHD boys manifested P3b amplitude decrements that were partially lateralized (i.e., maximal at left temporal scalp locations) as well as affected by maturation. These results indicate that ADHD boys suffer from deficits at both relatively early (sensory) and late (semantic) levels of visual selective information processing. The data also support the hypothesis that the visual selective processing deficits observed in the ADHD boys originate from deficits in the strength of activation of a neural network comprising prefrontal and occipito-temporal brain regions. This network seems to be actively engaged during attention to color and may contain the major intracerebral generating sources of the associated scalp-recorded ERP components.

Structural and energetic processes related to P300: LORETA findings in depression and effects of antidepressant drugs.

PubMed

Anderer, P; Saletu, B; Semlitsch, H V; Pascual-Marqui, R D

2002-01-01

Noninvasive electrophysiological neuroimaging applied to cognitive components of event-related potentials (ERPs) may differentiate between structural and energetic processes related to information processing. The structural level, revealed by the location of the local maxima of the current source density distribution, describes the time-dependent network of activated brain areas. The magnitude of the source strength, a measure of the energetic component, describes the allocation of processing resources. ERPs were recorded in an odd-ball paradigm and low-resolution brain electromagnetic tomography (LORETA) was applied for standard and target ERP components. In a group of 60 menopausal depressed patients of 45-60 years of age, reduced P300 source strength was observed bilaterally, temporally and medially prefrontally reaching to rostal parts of the anterior cingulate, compared with 29 age-matched controls. In a double-blind, placebo-controlled study, 2 mg of the antidepressant citalopram induced a significant increase of P300 source strength in the (left) prefrontal cortex and precuneus compared with placebo, reaching to the posterior cingulate. Similar increases were observed after 800 mg S-adenosyl-L-methionine (SAMe) administered intravenously in ten young healthy subjects aged 22-33, and they were even more pronounced in ten elderly healthy subjects aged 56-71. Thus, ERP-tomography identified changes in energetic sources in brain areas predominantly involved in depression and in antidepressant action.

Hands-On ERP Learning: Using OpenERP[R], an Alternative to SAP[R

ERIC Educational Resources Information Center

Ayyagari, Ramakrishna

2011-01-01

Recent struggles with ERP systems (Kanaracus, 2010) highlight that teaching ERP skills is still very relevant today. Previous research suggests that knowledge of ERP concepts is more important than skills with any particular ERP package (Strong et al., 2006). However, a review of published studies in "JISE" shows a bias towards commercial ERP…

Electrophysiological basis for the ability of olanzapine to improve verbal memory and functional outcome in patients with schizophrenia: a LORETA analysis of P300.

PubMed

Higuchi, Yuko; Sumiyoshi, Tomiki; Kawasaki, Yasuhiro; Matsui, Mie; Arai, Hirofumi; Kurachi, Masayoshi

2008-04-01

Abnormality of P300 waveforms of event-related potentials (ERPs) has been suggested to represent an aspect of the pathophysiology of schizophrenia. Previous work points to the contribution of altered neural function in discrete brain regions in the left hemisphere to psychotic symptoms and cognitive deficits of schizophrenia. In this study, we sought to determine: 1) if patients with schizophrenia elicit a decreased P300 current source density in brain areas, such as the superior temporal gyrus (STG); 2) if decreased P300 generator density in the left STG is recovered by treatment with the most widely-used antipsychotic drug olanzapine; and 3) if the recovery of P300 source density is associated with improvements of cognitive and functional status. P300 in response to an auditory oddball task, as well as verbal learning memory, psychopathology, and quality of life were evaluated in 16 right-handed patients with schizophrenia before and after treatment with olanzapine for 6 months. ERP data were also obtained from 16 right-handed age and gender-matched normal volunteers. Low resolution electromagnetic tomography (LORETA) analysis was used to obtain current density images of P300. Patients with schizophrenia showed significantly smaller LORETA values in several brain regions in the left side, particularly STG, middle frontal gyrus, and precentral gyrus, compared with control subjects. Six-month treatment with olanzapine significantly increased P300 source density only in the left STG. Positive symptoms, negative symptoms, verbal learning memory, and quality of life were also improved during treatment. Significant correlations were found between the increase in LORETA values of left STG vs. improvements of negative symptoms, as measured by Scale for the Assessment of the Negative Symptoms, and verbal learning memory, as measured by the Japanese Verbal Learning Test. Improvement of quality of life, as evaluated by the Quality of Life Scale, were significantly associated with an increase in LORETA values of middle frontal gyrus, and tended to correlate with that of precentral gyrus. The results of this study suggest that changes in cortical activity, as measured by ERPs, are responsible for the ability of some antipsychotic drugs to improve cognition and functional outcome in patients with schizophrenia.

Using ERP and WfM Systems for Implementing Business Processes: An Empirical Study

NASA Astrophysics Data System (ADS)

Aversano, Lerina; Tortorella, Maria

Software systems mainly considered from enterprises for dealing with a business process automation belong to the following two categories: Workflow Management Systems (WfMS) and Enterprise Resource Planning (ERP) systems. The wider diffusion of ERP systems tends to favourite this solution, but there are several limitations of most ERP systems for automating business processes. This paper reports an empirical study aiming at comparing the ability of implementing business processes of ERP systems and WfMSs. Two different case studies have been considered in the empirical study. It evaluates and analyses the correctness and completeness of the process models implemented by using ERP and WfM systems.

Retrieving self-vocalized information: An event-related potential (ERP) study on the effect of retrieval orientation.

PubMed

Rosburg, Timm; Johansson, Mikael; Sprondel, Volker; Mecklinger, Axel

2014-11-18

Retrieval orientation refers to a pre-retrieval process and conceptualizes the specific form of processing that is applied to a retrieval cue. In the current event-related potential (ERP) study, we sought to find evidence for an involvement of the auditory cortex when subjects attempt to retrieve vocalized information, and hypothesized that adopting retrieval orientation would be beneficial for retrieval accuracy. During study, participants saw object words that they subsequently vocalized or visually imagined. At test, participants had to identify object names of one study condition as targets and to reject object names of the second condition together with new items. Target category switched after half of the test trials. Behaviorally, participants responded less accurately and more slowly to targets of the vocalize condition than to targets of the imagine condition. ERPs to new items varied at a single left electrode (T7) between 500 and 800ms, indicating a moderate retrieval orientation effect in the subject group as a whole. However, whereas the effect was strongly pronounced in participants with high retrieval accuracy, it was absent in participants with low retrieval accuracy. A current source density (CSD) mapping of the retrieval orientation effect indicated a source over left temporal regions. Independently from retrieval accuracy, the ERP retrieval orientation effect was surprisingly also modulated by test order. Findings are suggestive for an involvement of the auditory cortex in retrieval attempts of vocalized information and confirm that adopting retrieval orientation is potentially beneficial for retrieval accuracy. The effects of test order on retrieval-related processes might reflect a stronger focus on the newness of items in the more difficult test condition when participants started with this condition. Copyright © 2014 Elsevier Inc. All rights reserved.

Long-Term Effects of Concussion on Electrophysiological Indices of Attention in Varsity College Athletes: An Event-Related Potential and Standardized Low-Resolution Brain Electromagnetic Tomography Approach.

PubMed

Ledwidge, Patrick S; Molfese, Dennis L

2016-12-01

This study investigated the effects of a past concussion on electrophysiological indices of attention in college athletes. Forty-four varsity football athletes (22 with at least one past concussion) participated in three neuropsychological tests and a two-tone auditory oddball task while undergoing high-density event-related potential (ERP) recording. Athletes previously diagnosed with a concussion experienced their most recent injury approximately 4 years before testing. Previously concussed and control athletes performed equivalently on three neuropsychological tests. Behavioral accuracy and reaction times on the oddball task were also equivalent across groups. However, athletes with a concussion history exhibited significantly larger N2 and P3b amplitudes and longer P3b latencies. Source localization using standardized low-resolution brain electromagnetic tomography indicated that athletes with a history of concussion generated larger electrical current density in the left inferior parietal gyrus compared to control athletes. These findings support the hypothesis that individuals with a past concussion recruit compensatory neural resources in order to meet executive functioning demands. High-density ERP measures combined with source localization provide an important method to detect long-term neural consequences of concussion in the absence of impaired neuropsychological performance.

Long-Term Effects of Concussion on Electrophysiological Indices of Attention in Varsity College Athletes: An Event-Related Potential and Standardized Low-Resolution Brain Electromagnetic Tomography Approach

PubMed Central

Molfese, Dennis L.

2016-01-01

Abstract This study investigated the effects of a past concussion on electrophysiological indices of attention in college athletes. Forty-four varsity football athletes (22 with at least one past concussion) participated in three neuropsychological tests and a two-tone auditory oddball task while undergoing high-density event-related potential (ERP) recording. Athletes previously diagnosed with a concussion experienced their most recent injury approximately 4 years before testing. Previously concussed and control athletes performed equivalently on three neuropsychological tests. Behavioral accuracy and reaction times on the oddball task were also equivalent across groups. However, athletes with a concussion history exhibited significantly larger N2 and P3b amplitudes and longer P3b latencies. Source localization using standardized low-resolution brain electromagnetic tomography indicated that athletes with a history of concussion generated larger electrical current density in the left inferior parietal gyrus compared to control athletes. These findings support the hypothesis that individuals with a past concussion recruit compensatory neural resources in order to meet executive functioning demands. High-density ERP measures combined with source localization provide an important method to detect long-term neural consequences of concussion in the absence of impaired neuropsychological performance. PMID:27025905

Increased ERp57 Expression in HBV-Related Hepatocellular Carcinoma: Possible Correlation and Prognosis.

PubMed

Liu, Miao; Du, Lingyao; He, Zhiliang; Yan, Libo; Shi, Ying; Shang, Jin; Tang, Hong

2017-01-01

Aim. ERp57 is involved in virus induced endoplasmic reticulum stress (ERS) and plays an important role in tumorigenesis. This study aimed to find whether HBV infection altered ERp57 expression and whether ERp57 regulation was involved in hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) genesis. Materials and Methods. HBV-HCC tissues, chronic hepatitis B (CHB) liver tissues, and normal liver tissues were acquired. ERp57 expressions in these tissues were detected through immunohistochemistry (IHC). And ERp57 expression in liver cell line L02, HBV replicative liver cell line L02-pHBV4.1, and HCC cell lines were detected through western blot for verification. Then medical data on patients providing HCC tissues were collected and analyzed along with ERp57 expression. Results. Higher ERp57 expression was found in HCC and CHB tissues ( p < 0.001). And HCC cell lines and L02-pHBV4.1 presented higher ERp57 expression as well. In patients, ERp57 expression showed significant differences between death and survival groups ( p = 0.037). And cumulative survival in patients with higher ERp57 (score ⩾ 8.75) is significantly lower ( p = 0.009). Conclusion. Our study found increased expression of ERp57 in HBV-HCC. Such altered expression could be related to HBV infection and high ERp57 expression may lead to poor prognosis of HBV-HCC patients.

Tracking the Time Course of Word-Frequency Effects in Auditory Word Recognition with Event-Related Potentials

ERIC Educational Resources Information Center

Dufour, Sophie; Brunelliere, Angele; Frauenfelder, Ulrich H.

2013-01-01

Although the word-frequency effect is one of the most established findings in spoken-word recognition, the precise processing locus of this effect is still a topic of debate. In this study, we used event-related potentials (ERPs) to track the time course of the word-frequency effect. In addition, the neighborhood density effect, which is known to…

Materials Data on ErP (SG:225) by Materials Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristin Persson

2015-02-09

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Materials Data on ErP (SG:221) by Materials Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristin Persson

2016-07-27

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

Enhanced long-term recollection for emotional pictures: evidence from high-density ERPs.

PubMed

Weymar, Mathias; Löw, Andreas; Melzig, Christiane A; Hamm, Alfons O

2009-11-01

The present study used behavioral and electrophysiological measures to investigate the processes mediating long-term recognition memory for emotional and neutral pictures. The results show enhanced memory recollection for emotional arousing pictures compared to neutral low arousing pictures. In accordance with the behavioral data, we observed enhanced old/new effects in the ERPs for emotionally arousing pictures in the recollection-sensitive old/new component at centro-parietal sites (500-800 ms). Moreover, early old/new effects were present over frontal and parietal sites (300-500 ms) irrespective of picture contents. Analysis of the subjective awareness, indexed by the confidence ratings, showed that the late parietal old/new effect was increased for high confidence responses whereas the early component (300-500 ms) was mainly driven by low confidence responses, an indication for familiarity based recognition processes.

Prevalence and associated factors of early repolarization pattern in healthy young northeastern Thai men: A correlation study with Brugada electrocardiography

PubMed Central

Makarawate, Pattarapong; Chaosuwannakit, Narumol; Ruamcharoen, Yossavadee; Panthongviriyakul, Aunejit; Pongchaiyakul, Choowong; Tharaksa, Prapapan; Sripo, Temsiri; Sawanyawisuth, Kittisak

2015-01-01

Background Early repolarization pattern (ERP) is characterized by J-point elevation with QRS notching or slurring in the terminal portion of the QRS complex. It may be associated with sudden death. Brugada syndrome (BS) is a genetic and fatal disease commonly found in northeastern Thai men. Data on the rate and predictors of ERP in Asian populations are limited. In addition, the correlation between ERP and BS has never been studied in an endemic area of BS. This study aimed to evaluate the prevalence of ERP and its associated factors in young, healthy male Asian subjects. Methods Between June 2011 and May 2012, 282 young, healthy men aged 20–45 years were enrolled at check-up clinics in Khon Kaen, Thailand. Subjects were divided into the ERP and non-ERP groups. Results There were 29 subjects with ERP (10.3%). The Sokolow–Lyon index was an independent factor for ERP with an adjusted odds ratio of 1.090 (95% CI: 1.027, 1.159). The Brugada ECG pattern was found in 11 (37.9%) subjects in the ERP group. The Brugada ECG pattern (non-type 1) was commonly found in lateral ERP patients. After the placement of high intercostal leads, the Brugada ECG pattern was dramatically increased compared with results obtained during standard ECG lead placement. Conclusions The ERP rate in young, healthy men from northeastern Thailand was 10.3%. A higher Sokolow–Lyon index was the only independent factor associated with ERP. Subjects with ERP should be examined with high intercostal leads to uncover Brugada ECG. PMID:26336562

An electrophysiological investigation of non-symbolic magnitude processing: numerical distance effects in children with and without mathematical learning disabilities.

PubMed

Heine, Angela; Wissmann, Jacqueline; Tamm, Sascha; De Smedt, Bert; Schneider, Michael; Stern, Elsbeth; Verschaffel, Lieven; Jacobs, Arthur M

2013-09-01

The aim of the present study was to probe electrophysiological effects of non-symbolic numerical processing in 20 children with mathematical learning disabilities (mean age = 99.2 months) compared to a group of 20 typically developing matched controls (mean age = 98.4 months). EEG data were obtained while children were tested with a standard non-symbolic numerical comparison paradigm that allowed us to investigate the effects of numerical distance manipulations for different set sizes, i.e., the classical subitizing, counting and estimation ranges. Effects of numerical distance manipulations on event-related potential (ERP) amplitudes as well as activation patterns of underlying current sources were analyzed. In typically developing children, the amplitudes of a late parietal positive-going ERP component showed systematic numerical distance effects that did not depend on set size. For the group of children with mathematical learning disabilities, ERP distance effects were found only for stimuli within the subitizing range. Current source density analysis of distance-related group effects suggested that areas in right inferior parietal regions are involved in the generation of the parietal ERP amplitude differences. Our results suggest that right inferior parietal regions are recruited differentially by controls compared to children with mathematical learning disabilities in response to non-symbolic numerical magnitude processing tasks, but only for stimuli with set sizes that exceed the subitizing range. Copyright © 2012 Elsevier Ltd. All rights reserved.

Time-course of trigeminal versus olfactory stimulation: evidence from chemosensory evoked potentials.

PubMed

Flohr, Elena L R; Boesveldt, Sanne; Haehner, Antje; Iannilli, Emilia; Sinding, Charlotte; Hummel, Thomas

2015-03-01

Habituation of responses to chemosensory signals has been explored in many ways. Strong habituation and adaptation processes can be observed at the various levels of processing. For example, with repeated exposure, amplitudes of chemosensory event-related potentials (ERP) decrease over time. However, long-term habituation has not been investigated so far and investigations of differences in habituation between trigeminal and olfactory ERPs are very rare. The present study investigated habituation over a period of approximately 80 min for two olfactory and one trigeminal stimulus, respectively. Habituation was examined analyzing the N1 and P2 amplitudes and latencies of chemosensory ERPs and intensity ratings. It was shown that amplitudes of both components - and intensity ratings - decreased from the first to the last block. Concerning ERP latencies no effects of habituation were seen. Amplitudes of trigeminal ERPs diminished faster than amplitudes of olfactory ERPs, indicating that the habituation of trigeminal ERPs is stronger than habituation of olfactory ERPs. Amplitudes of trigeminal ERPs were generally higher than amplitudes of olfactory ERPs, as it has been shown in various studies before. The results reflect relatively selective central changes in response to chemosensory stimuli over time. Copyright © 2015 Elsevier B.V. All rights reserved.

Interaction of Erp Protein of Mycobacterium tuberculosis with Rv2212 Enhances Intracellular Survival of Mycobacterium smegmatis.

PubMed

Ganaie, Arsheed Ahmad; Trivedi, Garima; Kaur, Amanpreet; Jha, Sidharth Shankar; Anand, Shashi; Rana, Vibhuti; Singh, Amit; Kumar, Shekhar; Sharma, Charu

2016-10-15

The Mycobacterium tuberculosis exported repetitive protein (RvErp) is a crucial virulence-associated factor as determined by its role in the survival and multiplication of mycobacteria in cultured macrophages and in vivo Although attempts have been made to understand the function of Erp protein, its exact role in Mycobacterium pathogenesis is still elusive. One way to determine this is by searching for novel interactions of RvErp. Using a yeast two-hybrid assay, an adenylyl cyclase (AC), Rv2212, was found to interact with RvErp. The interaction between RvErp and Rv2212 is direct and occurs at the endogenous level. The Erp protein of Mycobacterium smegmatis (MSMEG_6405, or MsErp) interacts neither with Rv2212 nor with Ms_4279, the M. smegmatis homologue of Rv2212. Deletion mutants of Rv2212 revealed its adenylyl cyclase domain to be responsible for the interaction. RvErp enhances Rv2212-mediated cyclic AMP (cAMP) production. Also, the biological significance of the interaction between RvErp and Rv2212 was demonstrated by the enhanced survival of M. smegmatis within THP-1 macrophages. Taken together, these studies address a novel mechanism by which Erp executes its function. RvErp is one of the important virulence factors of M. tuberculosis This study describes a novel function of RvErp protein of M. tuberculosis by identifying Rv2212 as its interacting protein. Rv2212 is an adenylyl cyclase (AC) and produces cAMP, one of the prime second messengers that regulate the intracellular survival of mycobacteria. Therefore, the significance of investigating novel interactions of RvErp is paramount in unraveling the mechanisms governing the intracellular survival of mycobacteria. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

A method for quantifying limbal stem cell niches using OCT imaging.

PubMed

Haagdorens, Michel; Behaegel, Joséphine; Rozema, Jos; Van Gerwen, Veerle; Michiels, Sofie; Ní Dhubhghaill, Sorcha; Tassignon, Marie-José; Zakaria, Nadia

2017-09-01

To evaluate the efficacy of Fourier domain-optical coherence tomography (FD-OCT) in imaging and quantifying the limbal palisades of Vogt and to correlate these images with histological findings. The superior and inferior limbal region of both eyes of 50 healthy volunteers were imaged by FD-OCT. Images were processed and analysed using Matlab software. In vitro immunofluorescent staining of a cadaveric donor limbus was analysed to correlate the presence of stem cells in the visualised structures. FD-OCT could successfully visualise limbal crypts and the palisades of Vogt in the limbus region. Fluorescent labelling confirmed the presence of stem cells in these structures. The mean palisade ridge width (Δ PR ) and the mean interpalisade epithelial rete peg width (Δ ERP ) were both of the order of 72 μm, leading to a palisade density (PD) of about 7.4 palisades/mm . A significant difference in Δ PR , Δ ERP and PD was seen between the inferior and superior sides of the right eye and the superior sides of the left and right eye(p<0.05.). A significant influence of iris colour on parameters Δ PR , Δ ERP and PD was found, and of age on PD and Δ ERP (p<0.05). In vivo OCT imaging is a safe and effective modality to image the limbus and can be used to visualise the palisades of Vogt. Image processing using Matlab software enabled quantification and density calculation of imaged limbal palisades of Vogt. This technique may enhance targeted limbal biopsies for transplantation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Polygenic pleiotropy and potential causal relationships between educational attainment, neurobiological profile, and positive psychotic symptoms.

PubMed

Lin, Yen-Feng; Chen, Chia-Yen; Öngür, Dost; Betensky, Rebecca; Smoller, Jordan W; Blacker, Deborah; Hall, Mei-Hua

2018-05-16

Event-related potential (ERP) components have been used to assess cognitive functions in patients with psychotic illness. Evidence suggests that among patients with psychosis there is a distinct heritable neurophysiologic phenotypic subtype captured by impairments across a range of ERP measures. In this study, we investigated the genetic basis of this "globally impaired" ERP cluster and its relationship to psychosis and cognitive abilities. We applied K-means clustering to six ERP measures to re-derive the globally impaired (n = 60) and the non-globally impaired ERP clusters (n = 323) in a sample of cases with schizophrenia (SCZ = 136) or bipolar disorder (BPD = 121) and healthy controls (n = 126). We used genome-wide association study (GWAS) results for SCZ, BPD, college completion, and childhood intelligence as the discovery datasets to derive polygenic risk scores (PRS) in our study sample and tested their associations with globally impaired ERP. We conducted mediation analyses to estimate the proportion of each PRS effect on severity of psychotic symptoms that is mediated through membership in the globally impaired ERP. Individuals with globally impaired ERP had significantly higher PANSS-positive scores (β = 3.95, P = 0.005). The SCZ-PRS was nominally associated with globally impaired ERP (unadjusted P = 0.01; R 2  = 3.07%). We also found a significant positive association between the college-PRS and globally impaired ERP (FDR-corrected P = 0.004; R 2  = 6.15%). The effect of college-PRS on PANSS positivity was almost entirely (97.1%) mediated through globally impaired ERP. These results suggest that the globally impaired ERP phenotype may represent some aspects of brain physiology on the path between genetic influences on educational attainment and psychotic symptoms.

An empirical identification and categorisation of training best practices for ERP implementation projects

NASA Astrophysics Data System (ADS)

Esteves, Jose Manuel

2014-11-01

Although training is one of the most cited critical success factors in Enterprise Resource Planning (ERP) systems implementations, few empirical studies have attempted to examine the characteristics of management of the training process within ERP implementation projects. Based on the data gathered from a sample of 158 respondents across four stakeholder groups involved in ERP implementation projects, and using a mixed method design, we have assembled a derived set of training best practices. Results suggest that the categorised list of ERP training best practices can be used to better understand training activities in ERP implementation projects. Furthermore, the results reveal that the company size and location have an impact on the relevance of training best practices. This empirical study also highlights the need to investigate the role of informal workplace trainers in ERP training activities.

Effects of people-centred factors on enterprise resource planning implementation project success: empirical evidence from Sri Lanka

NASA Astrophysics Data System (ADS)

Wickramasinghe, Vathsala; Gunawardena, Vathsala

2010-08-01

Extant literature suggests people-centred factors as one of the major areas influencing enterprise resource planning (ERP) implementation project success. Yet, to date, few empirical studies attempted to validate the link between people-centred factors and ERP implementation project success. The purpose of this study is to empirically identify people-centred factors that are critical to ERP implementation projects in Sri Lanka. The study develops and empirically validates a framework for people-centred factors that influence the success of ERP implementation projects. Survey research methodology was used and collected data from 74 ERP implementation projects in Sri Lanka. The people-centred factors of 'project team competence', 'rewards' and 'communication and change' were found to predict significantly the ERP implementation project success.

A Comparative Study of Average, Linked Mastoid, and REST References for ERP Components Acquired during fMRI

PubMed Central

Yang, Ping; Fan, Chenggui; Wang, Min; Li, Ling

2017-01-01

In simultaneous electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI) studies, average reference (AR), and digitally linked mastoid (LM) are popular re-referencing techniques in event-related potential (ERP) analyses. However, they may introduce their own physiological signals and alter the EEG/ERP outcome. A reference electrode standardization technique (REST) that calculated a reference point at infinity was proposed to solve this problem. To confirm the advantage of REST in ERP analyses of synchronous EEG-fMRI studies, we compared the reference effect of AR, LM, and REST on task-related ERP results of a working memory task during an fMRI scan. As we hypothesized, we found that the adopted reference did not change the topography map of ERP components (N1 and P300 in the present study), but it did alter the task-related effect on ERP components. LM decreased or eliminated the visual working memory (VWM) load effect on P300, and the AR distorted the distribution of VWM location-related effect at left posterior electrodes as shown in the statistical parametric scalp mapping (SPSM) of N1. ERP cortical source estimates, which are independent of the EEG reference choice, were used as the golden standard to infer the relative utility of different references on the ERP task-related effect. By comparison, REST reference provided a more integrated and reasonable result. These results were further confirmed by the results of fMRI activations and a corresponding EEG-only study. Thus, we recommend the REST, especially with a realistic head model, as the optimal reference method for ERP data analysis in simultaneous EEG-fMRI studies. PMID:28529472

A Comparative Study of Average, Linked Mastoid, and REST References for ERP Components Acquired during fMRI.

PubMed

Yang, Ping; Fan, Chenggui; Wang, Min; Li, Ling

2017-01-01

In simultaneous electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI) studies, average reference (AR), and digitally linked mastoid (LM) are popular re-referencing techniques in event-related potential (ERP) analyses. However, they may introduce their own physiological signals and alter the EEG/ERP outcome. A reference electrode standardization technique (REST) that calculated a reference point at infinity was proposed to solve this problem. To confirm the advantage of REST in ERP analyses of synchronous EEG-fMRI studies, we compared the reference effect of AR, LM, and REST on task-related ERP results of a working memory task during an fMRI scan. As we hypothesized, we found that the adopted reference did not change the topography map of ERP components (N1 and P300 in the present study), but it did alter the task-related effect on ERP components. LM decreased or eliminated the visual working memory (VWM) load effect on P300, and the AR distorted the distribution of VWM location-related effect at left posterior electrodes as shown in the statistical parametric scalp mapping (SPSM) of N1. ERP cortical source estimates, which are independent of the EEG reference choice, were used as the golden standard to infer the relative utility of different references on the ERP task-related effect. By comparison, REST reference provided a more integrated and reasonable result. These results were further confirmed by the results of fMRI activations and a corresponding EEG-only study. Thus, we recommend the REST, especially with a realistic head model, as the optimal reference method for ERP data analysis in simultaneous EEG-fMRI studies.

Training and testing ERP-BCIs under different mental workload conditions

NASA Astrophysics Data System (ADS)

Ke, Yufeng; Wang, Peiyuan; Chen, Yuqian; Gu, Bin; Qi, Hongzhi; Zhou, Peng; Ming, Dong

2016-02-01

Objective. As one of the most popular and extensively studied paradigms of brain-computer interfaces (BCIs), event-related potential-based BCIs (ERP-BCIs) are usually built and tested in ideal laboratory settings in most existing studies, with subjects concentrating on stimuli and intentionally avoiding possible distractors. This study is aimed at examining the effect of simultaneous mental activities on ERP-BCIs by manipulating various levels of mental workload during the training and/or testing of an ERP-BCI. Approach. Mental workload was manipulated during the training or testing of a row-column P300-speller to investigate how and to what extent the spelling performance and the ERPs evoked by the oddball stimuli are affected by simultaneous mental workload. Main results. Responses of certain ERP components, temporal-occipital N200 and the late reorienting negativity evoked by the oddball stimuli and the classifiability of ERP features between targets and non-targets decreased with the increase of mental workload encountered by the subject. However, the effect of mental workload on the performance of ERP-BCI was not always negative but depended on the conditions where the ERP-BCI was built and applied. The performance of ERP-BCI built under an ideal lab setting without any irrelevant mental activities declined with the increasing mental workload of the testing data. However, the performance was significantly improved when an ERP-BCI was built under an appropriate mental workload level, compared to that built under speller-only conditions. Significance. The adverse effect of concurrent mental activities may present a challenge for ERP-BCIs trained in ideal lab settings but which are to be used in daily work, especially when users are performing demanding mental processing. On the other hand, the positive effects of the mental workload of the training data suggest that introducing appropriate mental workload during training ERP-BCIs is of potential benefit to the performance in practical applications.

Event-Related Potentials (ERPs) in Second Language Research: A Brief Introduction to the Technique, a Selected Review, and an Invitation to Reconsider Critical Periods in L2

ERIC Educational Resources Information Center

Steinhauer, Karsten

2014-01-01

This article provides a selective overview of recent event-related brain potential (ERP) studies in L2 morpho-syntax, demonstrating that the ERP evidence supporting the critical period hypothesis (CPH) may be less compelling than previously thought. The article starts with a general introduction to ERP methodology and language-related ERP profiles…

Classifying four-category visual objects using multiple ERP components in single-trial ERP.

PubMed

Qin, Yu; Zhan, Yu; Wang, Changming; Zhang, Jiacai; Yao, Li; Guo, Xiaojuan; Wu, Xia; Hu, Bin

2016-08-01

Object categorization using single-trial electroencephalography (EEG) data measured while participants view images has been studied intensively. In previous studies, multiple event-related potential (ERP) components (e.g., P1, N1, P2, and P3) were used to improve the performance of object categorization of visual stimuli. In this study, we introduce a novel method that uses multiple-kernel support vector machine to fuse multiple ERP component features. We investigate whether fusing the potential complementary information of different ERP components (e.g., P1, N1, P2a, and P2b) can improve the performance of four-category visual object classification in single-trial EEGs. We also compare the classification accuracy of different ERP component fusion methods. Our experimental results indicate that the classification accuracy increases through multiple ERP fusion. Additional comparative analyses indicate that the multiple-kernel fusion method can achieve a mean classification accuracy higher than 72 %, which is substantially better than that achieved with any single ERP component feature (55.07 % for the best single ERP component, N1). We compare the classification results with those of other fusion methods and determine that the accuracy of the multiple-kernel fusion method is 5.47, 4.06, and 16.90 % higher than those of feature concatenation, feature extraction, and decision fusion, respectively. Our study shows that our multiple-kernel fusion method outperforms other fusion methods and thus provides a means to improve the classification performance of single-trial ERPs in brain-computer interface research.

Mindfulness-based exposure and response prevention for obsessive compulsive disorder: study protocol for a pilot randomised controlled trial.

PubMed

Strauss, Clara; Rosten, Claire; Hayward, Mark; Lea, Laura; Forrester, Elizabeth; Jones, Anna-Marie

2015-04-16

Obsessive Compulsive Disorder (OCD) is a distressing and debilitating condition affecting 1-2% of the population. Exposure and response prevention (ERP) is a behaviour therapy for OCD with the strongest evidence for effectiveness of any psychological therapy for the condition. Even so, only about half of people offered ERP show recovery after the therapy. An important reason for ERP failure is that about 25% of people drop out early, and even for those who continue with the therapy, many do not regularly engage in ERP tasks, an essential element of ERP. A mindfulness-based approach has the potential to reduce drop-out from ERP and to improve ERP task engagement with an emphasis on accepting difficult thoughts, feelings and bodily sessions and on becoming more aware of urges, rather than automatically acting on them. This is a pilot randomised controlled trial of mindfulness-based ERP (MB-ERP) with the aim of establishing parameters for a definitive trial. Forty participants diagnosed with OCD will be allocated at random to a 10-session ERP group or to a 10-session MB-ERP group. Primary outcomes are OCD symptom severity and therapy engagement. Secondary outcomes are depressive symptom severity, wellbeing and obsessive-compulsive beliefs. A semi-structured interview with participants will guide understanding of change processes. Findings from this pilot study will inform future research in this area, and if effect sizes on primary outcomes are in favour of MB-ERP in comparison to ERP, funding for a definitive trial will be sought. Current Controlled Trials registration number ISRCTN52684820. Registered on 30 January 2014.

Teaching Medium-Sized ERP Systems - A Problem-Based Learning Approach

NASA Astrophysics Data System (ADS)

Winkelmann, Axel; Matzner, Martin

In order to increase the diversity in IS education, we discuss an approach for teaching medium-sized ERP systems in master courses. Many of today's IS curricula are biased toward large ERP packages. Nevertheless, these ERP systems are only a part of the ERP market. Hence, this chapter describes a course outline for a course on medium-sized ERP systems. Students had to study, analyze, and compare five different ERP systems during a semester. The chapter introduces a procedure model and scenario for setting up similar courses at other universities. Furthermore, it describes some of the students' outcomes and evaluates the contribution of the course with regard to a practical but also academic IS education.

Reward contingencies and the recalibration of task monitoring and reward systems: a high-density electrical mapping study.

PubMed

Morie, K P; De Sanctis, P; Foxe, J J

2014-07-25

Task execution almost always occurs in the context of reward-seeking or punishment-avoiding behavior. As such, ongoing task-monitoring systems are influenced by reward anticipation systems. In turn, when a task has been executed either successfully or unsuccessfully, future iterations of that task will be re-titrated on the basis of the task outcome. Here, we examined the neural underpinnings of the task-monitoring and reward-evaluation systems to better understand how they govern reward-seeking behavior. Twenty-three healthy adult participants performed a task where they accrued points that equated to real world value (gift cards) by responding as rapidly as possible within an allotted timeframe, while success rate was titrated online by changing the duration of the timeframe dependent on participant performance. Informative cues initiated each trial, indicating the probability of potential reward or loss (four levels from very low to very high). We manipulated feedback by first informing participants of task success/failure, after which a second feedback signal indicated actual magnitude of reward/loss. High-density electroencephalography (EEG) recordings allowed for examination of event-related potentials (ERPs) to the informative cues and in turn, to both feedback signals. Distinct ERP components associated with reward cues, task-preparatory and task-monitoring processes, and reward feedback processes were identified. Unsurprisingly, participants displayed increased ERP amplitudes associated with task-preparatory processes following cues that predicted higher chances of reward. They also rapidly updated reward and loss prediction information dependent on task performance after the first feedback signal. Finally, upon reward receipt, initial reward probability was no longer taken into account. Rather, ERP measures suggested that only the magnitude of actual reward or loss was now processed. Reward and task-monitoring processes are clearly dissociable, but interact across very fast timescales to update reward predictions as information about task success or failure is accrued. Careful delineation of these processes will be useful in future investigations in clinical groups where such processes are suspected of having gone awry. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Reward Contingencies and the Recalibration of Task Monitoring and Reward Systems: A high-density electrical mapping study

PubMed Central

Morie, Kristen P.; De Sanctis, Pierfilippo; Foxe, John J.

2014-01-01

Task execution almost always occurs in the context of reward-seeking or punishment-avoiding behavior. As such, ongoing task monitoring systems are influenced by reward anticipation systems. In turn, when a task has been executed either successfully or unsuccessfully, future iterations of that task will be re-titrated on the basis of the task outcome. Here, we examined the neural underpinnings of the task-monitoring and reward-evaluation systems to better understand how they govern reward seeking behavior. Twenty-three healthy adult participants performed a task where they accrued points that equated to real world value (gift cards) by responding as rapidly as possible within an allotted timeframe, while success rate was titrated online by changing the duration of the timeframe dependent on participant performance. Informative cues initiated each trial, indicating the probability of potential reward or loss (four levels from very low to very high). We manipulated feedback by first informing participants of task success/failure, after which a second feedback signal indicated actual magnitude of reward/loss. High-density EEG recordings allowed for examination of event-related potentials (ERPs) to the informative cues and in turn, to both feedback signals. Distinct ERP components associated with reward cues, task preparatory and task monitoring processes, and reward feedback processes were identified. Unsurprisingly, participants displayed increased ERP amplitudes associated with task preparatory processes following cues that predicted higher chances of reward. They also rapidly updated reward and loss prediction information dependent on task performance after the first feedback signal. Finally, upon reward receipt, initial reward probability was no longer taken into account. Rather, ERP measures suggested that only the magnitude of actual reward or loss was now processed. Reward and task monitoring processes are clearly dissociable, but interact across very fast timescales to update reward predictions as information about task success or failure is accrued. Careful delineation of these processes will be useful in future investigations in clinical groups where such processes are suspected of having gone awry. PMID:24836852

Stereo Viewing Modulates Three-Dimensional Shape Processing During Object Recognition: A High-Density ERP Study

PubMed Central

2017-01-01

The role of stereo disparity in the recognition of 3-dimensional (3D) object shape remains an unresolved issue for theoretical models of the human visual system. We examined this issue using high-density (128 channel) recordings of event-related potentials (ERPs). A recognition memory task was used in which observers were trained to recognize a subset of complex, multipart, 3D novel objects under conditions of either (bi-) monocular or stereo viewing. In a subsequent test phase they discriminated previously trained targets from untrained distractor objects that shared either local parts, 3D spatial configuration, or neither dimension, across both previously seen and novel viewpoints. The behavioral data showed a stereo advantage for target recognition at untrained viewpoints. ERPs showed early differential amplitude modulations to shape similarity defined by local part structure and global 3D spatial configuration. This occurred initially during an N1 component around 145–190 ms poststimulus onset, and then subsequently during an N2/P3 component around 260–385 ms poststimulus onset. For mono viewing, amplitude modulation during the N1 was greatest between targets and distracters with different local parts for trained views only. For stereo viewing, amplitude modulation during the N2/P3 was greatest between targets and distracters with different global 3D spatial configurations and generalized across trained and untrained views. The results show that image classification is modulated by stereo information about the local part, and global 3D spatial configuration of object shape. The findings challenge current theoretical models that do not attribute functional significance to stereo input during the computation of 3D object shape. PMID:29022728

Effects of dextromethorphan/quinidine on auditory event-related potentials in multiple sclerosis patients with pseudobulbar affect.

PubMed

Haiman, Guy; Pratt, Hillel; Miller, Ariel

2009-10-01

The purpose of this study was to characterize the brain activity and associated cortical structures involved in pseudobulbar affect (PBA), a condition characterized by uncontrollable episodes of laughing and/or crying in patients with multiple sclerosis before and after treatment with dextromethorphan/quinidine (DM/Q). Behavioral responses and event-related potentials (ERPs) in response to subjectively significant and neutral verbal stimuli were recorded from 2 groups: 6 multiple sclerosis patients with PBA before (PBA-preTx) and after (PBA-DM/Q) treatment with DM/Q and 6 healthy control (HC) subjects. Statistical nonparametric mapping comparisons of ERP source current density distributions between groups were conducted for subjectively significant and neutral stimuli separately before and after treatment with DM/Q. Treatment with DM/Q had a normalizing effect on the behavioral responses of PBA patients. Event-related potential waveform comparisons of PBA-preTx and PBA-DM/Q with HC, for both neutral and subjectively significant stimuli, revealed effects on early ERP components. Comparisons between PBA-preTx and HC, in response to subjectively significant stimuli, revealed both early and late effects. Source analysis comparisons between PBA-preTx and PBA-DM/Q indicated distinct activations in areas involved in emotional processing and high-level and associative visual processing in response to neutral stimuli and in areas involved in emotional, somatosensory, primary, and premotor processing in response to subjectively significant stimuli. In most cases, stimuli evoked higher current density in PBA-DM/Q compared with the other groups. In conclusion, differences in brain activity were observed before and after medication. Also, DM/Q administration resulted in normalization of behavioral and electrophysiological measures.

Brain-wave measures of workload in advanced cockpits: The transition of technology from laboratory to cockpit simulator, phase 2

NASA Technical Reports Server (NTRS)

Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.

1989-01-01

The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.

[Localization of attention related cortical structures by evoked potentials].

PubMed

Szelenberger, W

2000-01-01

Attention is an ambiguous concept, difficult to direct implementation in neurophysiological studies. The paper presents application of the Continuous Attention Test (CAT) items as stimuli in event related potential (ERP) studies on attention. Stimuli with high demand of attention result in enlarged N1 component in occipital derivations. Spatial analysis revealed increased positivity in frontal derivations. Three-dimensional image of cortical current density by means of Low Resolution Electromagnetic Tomography (LORETA) revealed sources of N1 component in occipital, parietal and postero-temporal derivations with the maximal current value at 17 Brodmann area. After target stimuli increase of current density in frontal derivations was observed, with the maximal value in the left 9 Brodmann area.

Mind Wandering and Task-Focused Attention: ERP Correlates.

PubMed

Gonçalves, Óscar F; Rêgo, Gabriel; Conde, Tatiana; Leite, Jorge; Carvalho, Sandra; Lapenta, Olívia Morgan; Boggio, Paulo S

2018-05-15

Previous studies looking at how Mind Wandering (MW) impacts performance in distinct Focused Attention (FA) systems, using the Attention Network Task (ANT), showed that the presence of pure MW thoughts did not impact the overall performance of ANT (alert, orienting and conflict) performance. However, it still remains unclear if the lack of interference of MW in the ANT, reported at the behavioral level, has a neurophysiological correspondence. We hypothesize that a distinct cortical processing may be required to meet attentional demands during MW. The objective of the present study was to test if, given similar levels of ANT performance, individuals predominantly focusing on MW or FA show distinct cortical processing. Thirty-three healthy participants underwent an EEG high-density acquisition while they were performing the ANT. MW was assessed following the ANT using an adapted version of the Resting State Questionnaire (ReSQ). The following ERP's were analyzed: pN1, pP1, P1, N1, pN, and P3. At the behavioral level, participants were slower and less accurate when responding to incongruent than to congruent targets (conflict effect), benefiting from the presentation of the double (alerting effect) and spatial (orienting effect) cues. Consistent with the behavioral data, ERP's waves were discriminative of distinct attentional effects. However, these results remained true irrespective of the MW condition, suggesting that MW imposed no additional cortical demand in alert, orienting, and conflict attention tasks.

Preserved frontal memorial processing for pictures in patients with mild cognitive impairment.

PubMed

Ally, Brandon A; McKeever, Joshua D; Waring, Jill D; Budson, Andrew E

2009-08-01

Amnestic mild cognitive impairment (aMCI) has been conceptualized as a transitional stage between healthy aging and Alzheimer's disease (AD). Therefore, understanding which aspects of memory are impaired and which remain relatively intact in these patients can be useful in determining who will ultimately go on to develop AD, and subsequently designing interventions to help patients live more engaged and independent lives. The dual-process model posits that recognition memory decisions can rely on either familiarity or recollection. Whereas research is fairly consistent in showing impaired recollection in patients with aMCI, the results have been mixed regarding familiarity. A noted difference between these studies investigating familiarity has been stimulus type. The goal of the current investigation was to use high-density event-related potentials (ERPs) to help elucidate the neural correlates of recognition decisions in patients with aMCI for words and pictures. We also hoped to help answer the question of whether patients can rely on familiarity to support successful recognition. Patients and controls participated in separate recognition memory tests of words and pictures while ERPs were recorded during retrieval. Results showed that ERP components typically associated with familiarity and retrieval monitoring were similar between groups for pictures. However, these components were diminished in the patient group for words. Based on recent work, the authors discuss the possibility that implicit conceptual priming could have contributed to the enhanced ERP correlate of familiarity. Further, the authors address the possibility that enhanced retrieval monitoring may be needed to modulate increased familiarity engendered by pictures.

Brain responses to verbal stimuli among multiple sclerosis patients with pseudobulbar affect.

PubMed

Haiman, Guy; Pratt, Hillel; Miller, Ariel

2008-08-15

To characterize the brain activity and associated cortical structures involved in pseudobulbar affect (PBA), a condition characterized by uncontrollable episodes of emotional lability in patients with multiple sclerosis (MS). Behavioral responses and event related potentials (ERP) in response to subjectively significant and neutral verbal stimuli were recorded from 33 subjects in 3 groups: 1) MS patients with PBA (MS+PBA); 2) MS patients without PBA (MS); 3) Healthy control subjects (HC). Statistical non-parametric mapping comparisons of ERP source current density distributions between groups were conducted separately for subjectively significant and for neutral stimuli. Behavioral responses showed more impulsive performance in patients with PBA. As expected, almost all ERP waveform comparisons between the MS groups and controls were significant. Source analysis indicated significantly distinct activation in MS+PBA in the vicinity of the somatosensory and motor areas in response to neutral stimuli, and at pre-motor and supplementary motor areas in response to subjectively significant stimuli. Both subjectively significant and neutral stimuli evoked higher current density in MS+PBA compared to both other groups. PBA of MS patients involves cortical structures related to sensory-motor and emotional processing, in addition to overactive involvement of motor cortical areas in response to neutral stimuli. These results may suggest that a 'disinhibition' of a "gate control"-type mechanism for emotional expression may lead to the lower emotional expression threshold of pseudobulbar affect.

Application of the Satellite Triaxial Accelerometer Experiment to Atmospheric Density and Wind Studies.

DTIC Science & Technology

1982-03-04

AL. 84 MAR 82 UNCLASSIFIED RFGL-ERP-774 F/G 22/3, N ’IN ~11 IP LA M °3 MICROCOP MWoWNo TEST CHART MICROCOPY RESOLUTION TEST CHART M ATO MF OF SO MBS...V 0 . To refine the solution a new V = x Vy& VOZ ) is used to calculate a new p. This new p is then used to calculate new velocities. The process is

Minimal Information for Neural Electromagnetic Ontologies (MINEMO): A standards-compliant method for analysis and integration of event-related potentials (ERP) data

PubMed Central

Frishkoff, Gwen; Sydes, Jason; Mueller, Kurt; Frank, Robert; Curran, Tim; Connolly, John; Kilborn, Kerry; Molfese, Dennis; Perfetti, Charles; Malony, Allen

2011-01-01

We present MINEMO (Minimal Information for Neural ElectroMagnetic Ontologies), a checklist for the description of event-related potentials (ERP) studies. MINEMO extends MINI (Minimal Information for Neuroscience Investigations)to the ERP domain. Checklist terms are explicated in NEMO, a formal ontology that is designed to support ERP data sharing and integration. MINEMO is also linked to an ERP database and web application (the NEMO portal). Users upload their data and enter MINEMO information through the portal. The database then stores these entries in RDF (Resource Description Framework), along with summary metrics, i.e., spatial and temporal metadata. Together these spatial, temporal, and functional metadata provide a complete description of ERP data and the context in which these data were acquired. The RDF files then serve as inputs to ontology-based labeling and meta-analysis. Our ultimate goal is to represent ERPs using a rich semantic structure, so results can be queried at multiple levels, to stimulate novel hypotheses and to promote a high-level, integrative account of ERP results across diverse study methods and paradigms. PMID:22180824

The t-CWT: a new ERP detection and quantification method based on the continuous wavelet transform and Student's t-statistics.

PubMed

Bostanov, Vladimir; Kotchoubey, Boris

2006-12-01

This study was aimed at developing a method for extraction and assessment of event-related brain potentials (ERP) from single-trials. This method should be applicable in the assessment of single persons' ERPs and should be able to handle both single ERP components and whole waveforms. We adopted a recently developed ERP feature extraction method, the t-CWT, for the purposes of hypothesis testing in the statistical assessment of ERPs. The t-CWT is based on the continuous wavelet transform (CWT) and Student's t-statistics. The method was tested in two ERP paradigms, oddball and semantic priming, by assessing individual-participant data on a single-trial basis, and testing the significance of selected ERP components, P300 and N400, as well as of whole ERP waveforms. The t-CWT was also compared to other univariate and multivariate ERP assessment methods: peak picking, area computation, discrete wavelet transform (DWT) and principal component analysis (PCA). The t-CWT produced better results than all of the other assessment methods it was compared with. The t-CWT can be used as a reliable and powerful method for ERP-component detection and testing of statistical hypotheses concerning both single ERP components and whole waveforms extracted from either single persons' or group data. The t-CWT is the first such method based explicitly on the criteria of maximal statistical difference between two average ERPs in the time-frequency domain and is particularly suitable for ERP assessment of individual data (e.g. in clinical settings), but also for the investigation of small and/or novel ERP effects from group data.

Sustained attention in skilled and novice martial arts athletes: a study of event-related potentials and current sources.

PubMed

Sanchez-Lopez, Javier; Silva-Pereyra, Juan; Fernandez, Thalia

2016-01-01

Background. Research on sports has revealed that behavioral responses and event-related brain potentials (ERP) are better in expert than in novice athletes for sport-related tasks. Focused attention is essential for optimal athletic performance across different sports but mainly in combat disciplines. During combat, long periods of focused attention (i.e., sustained attention) are required for a good performance. Few investigations have reported effects of expertise on brain electrical activity and its neural generators during sport-unrelated attention tasks. The aim of the present study was to assess the effect of expertise (i.e., skilled and novice martial arts athletes) analyzing the ERP during a sustained attention task (Continuous Performance Task; CPT) and the cortical three-dimensional distribution of current density, using the sLORETA technique. Methods. CPT consisted in an oddball-type paradigm presentation of five stimuli (different pointing arrows) where only one of them (an arrow pointing up right) required a motor response (i.e., target). CPT was administered to skilled and novice martial arts athletes while EEG were recorded. Amplitude ERP data from target and non-target stimuli were compared between groups. Subsequently, current source analysis for each ERP component was performed on each subject. sLORETA images were compared by condition and group using Statistical Non-Parametric Mapping analysis. Results. Skilled athletes showed significant amplitude differences between target and non-target conditions in early ERP components (P100 and P200) as opposed to the novice group; however, skilled athletes showed no significant effect of condition in N200 but novices did show a significant effect. Current source analysis showed greater differences in activations in skilled compared with novice athletes between conditions in the frontal (mainly in the Superior Frontal Gyrus and Medial Frontal Gyrus) and limbic (mainly in the Anterior Cingulate Gyrus) lobes. Discussion. These results are supported by previous findings regarding activation of neural structures that underlie sustained attention. Our findings may indicate a better-controlled attention in skilled athletes, which suggests that expertise can improve effectiveness in allocation of attentional resources during the first stages of cognitive processing during combat.

ERP system implementation in SMEs: exploring the influences of the SME context

NASA Astrophysics Data System (ADS)

Zach, Ondrej; Munkvold, Bjørn Erik; Håkon Olsen, Dag

2014-03-01

Small and medium-sized enterprises (SMEs) are increasingly implementing enterprise resource planning (ERP) systems. Compared to large enterprises, SMEs differ in a number of inherent characteristics, which are likely to impact the ERP system implementations. The purpose of this study is to explore these influences of the SME context on the ERP system implementation process. SME characteristics are synthesised from relevant literature and the influences of the contextual factors on various activities across the ERP life cycle are investigated. The study presents findings from a multiple case study of four SMEs. The ownership type of the companies and limited resources were identified as the most influential contextual factors. Among the ERP life-cycle phases, the implementation phase was affected most by the SME context. The case studies also illustrate the need for a more nuanced view on what should be considered general characteristics of SMEs; for example, regarding the level of IS knowledge, business processes, and market characteristics.

Psychometric considerations in the measurement of event-related brain potentials: Guidelines for measurement and reporting.

PubMed

Clayson, Peter E; Miller, Gregory A

2017-01-01

Failing to consider psychometric issues related to reliability and validity, differential deficits, and statistical power potentially undermines the conclusions of a study. In research using event-related brain potentials (ERPs), numerous contextual factors (population sampled, task, data recording, analysis pipeline, etc.) can impact the reliability of ERP scores. The present review considers the contextual factors that influence ERP score reliability and the downstream effects that reliability has on statistical analyses. Given the context-dependent nature of ERPs, it is recommended that ERP score reliability be formally assessed on a study-by-study basis. Recommended guidelines for ERP studies include 1) reporting the threshold of acceptable reliability and reliability estimates for observed scores, 2) specifying the approach used to estimate reliability, and 3) justifying how trial-count minima were chosen. A reliability threshold for internal consistency of at least 0.70 is recommended, and a threshold of 0.80 is preferred. The review also advocates the use of generalizability theory for estimating score dependability (the generalizability theory analog to reliability) as an improvement on classical test theory reliability estimates, suggesting that the latter is less well suited to ERP research. To facilitate the calculation and reporting of dependability estimates, an open-source Matlab program, the ERP Reliability Analysis Toolbox, is presented. Copyright © 2016 Elsevier B.V. All rights reserved.

Friend or foe: Endoplasmic reticulum protein 29 (ERp29) in epithelial cancer

PubMed Central

Chen, Shaohua; Zhang, Daohai

2015-01-01

The endoplasmic reticulum (ER) protein 29 (ERp29) is a molecular chaperone that plays a critical role in protein secretion from the ER in eukaryotic cells. Recent studies have also shown that ERp29 plays a role in cancer. It has been demonstrated that ERp29 is inversely associated with primary tumor development and functions as a tumor suppressor by inducing cell growth arrest in breast cancer. However, ERp29 has also been reported to promote epithelial cell morphogenesis, cell survival against genotoxic stress and distant metastasis. In this review, we summarize the current understanding on the biological and pathological functions of ERp29 in cancer and discuss the pivotal aspects of ERp29 as “friend or foe” in epithelial cancer. PMID:25709888

Deployment of ERP Systems at Automotive Industries, Security Inspection (Case Study: IRAN KHODRO Automotive Company)

NASA Astrophysics Data System (ADS)

Ali, Hatamirad; Hasan, Mehrjerdi

Automotive industry and car production process is one of the most complex and large-scale production processes. Today, information technology (IT) and ERP systems incorporates a large portion of production processes. Without any integrated systems such as ERP, the production and supply chain processes will be tangled. The ERP systems, that are last generation of MRP systems, make produce and sale processes of these industries easier and this is the major factor of development of these industries anyhow. Today many of large-scale companies are developing and deploying the ERP systems. The ERP systems facilitate many of organization processes and make organization to increase efficiency. The security is a very important part of the ERP strategy at the organization, Security at the ERP systems, because of integrity and extensive, is more important of local and legacy systems. Disregarding of this point can play a giant role at success or failure of this kind of systems. The IRANKHODRO is the biggest automotive factory in the Middle East with an annual production over 600.000 cars. This paper presents ERP security deployment experience at the "IRANKHODRO Company". Recently, by launching ERP systems, it moved a big step toward more developments.

Managing the Challenges of Leadership in ERP Implementations: An Exploratory Study of the Leadership Challenges Encountered by Project Managers Involved in ERP Implementation Projects

ERIC Educational Resources Information Center

Wanjagi, James K.

2013-01-01

Increasingly, organizations are conducting more Enterprise Resource Planning (ERP) projects in order to promote organizational efficiencies. Meanwhile, minimal research has been conducted on the leadership challenges faced by project managers during the ERP project implementations and how these challenges are managed. The existing project…

Evaluation of the ERP dispersion model using Darlington tracer-study data. Report No. 90-200-K

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wright, S.C.

1990-01-01

In this study, site-boundary atmospheric dilution factors calculated by the atmospheric dispersion model used in the ERP (Emergency Response Planning) computer code were compared to data collected during the Darlington tracer study. The purpose of this comparison was to obtain estimates of model uncertainty under a variety of conditions. This report provides background on ERP, the ERP dispersion model and the Darlington tracer study. Model evaluation techniques are discussed briefly, and the results of the comparison of model calculations with the field data are presented and reviewed.

ERPs and Eye Movements Reflect Atypical Visual Perception in Pervasive Developmental Disorder

ERIC Educational Resources Information Center

Kemner, Chantal; van Engeland, Herman

2006-01-01

Many studies of eye tracking or event-related brain potentials (ERPs) in subjects with Pervasive Developmental Disorder (PDD) have yielded inconsistent results on attentional processing. However, recent studies have indicated that there are specific abnormalities in early processing that are probably related to perception. ERP amplitudes in…

A case study of exploiting enterprise resource planning requirements

NASA Astrophysics Data System (ADS)

Niu, Nan; Jin, Mingzhou; Cheng, Jing-Ru C.

2011-05-01

The requirements engineering (RE) processes have become a key to conceptualising corporate-wide integrated solutions based on packaged enterprise resource planning (ERP) software. The RE literature has mainly focused on procuring the most suitable ERP package. Little is known about how an organisation exploits the chosen ERP RE model to frame the business application development. This article reports an exploratory case study of a key tenet of ERP RE adoption, namely that aligning business applications to the packaged RE model leads to integral practices and economic development. The case study analysed a series interrelated pilot projects developed for a business division of a large IT manufacturing and service company, using Oracle's appl1ication implementation method (AIM). The study indicated that AIM RE improved team collaboration and project management experience, but needed to make hidden assumptions explicit to support data visibility and integrity. Our study can direct researchers towards rigorous empirical evaluations of ERP RE adoption, collect experiences and lessons learned for practitioners, and help generate more effective and mature processes when exploiting ERP RE methods.

Organization Readiness and ERP Implementation in Albaha University

NASA Astrophysics Data System (ADS)

Alaqeel, K.; Shakkah, M. S.; Rahmat, R. F.; Alfageeh, A.; Budiarto, R.

2017-04-01

This work studies the correlation between the organizational readiness in Albaha University and the respective Critical Success Factors with regards to the Enterprise Resource Planning (ERP) implementation. The study also considers some suggestions to improve the ABU’s ERP systems and roadmap towards the self -development strategy and to reduce vendor-dependency. A survey regarding ERP to the end-users, experts and developers in Albaha University was conducted. The analysis of the results in this work confirmed with the results of an existing work. The four significance success factors: Project Management, Business Process Re-engineering, System Integration, and Training and Education are recommended to be adopted to assure the smooth adoption of ERP at Albaha University.

The utility of event-related potentials (ERPs) in understanding food-related cognition: A systematic review and recommendations.

PubMed

Carbine, Kaylie A; Rodeback, Rebekah; Modersitzki, Erin; Miner, Marshall; LeCheminant, James D; Larson, Michael J

2018-05-19

Daily dietary decisions have the potential to impact our physical, mental, and emotional health. Event-related potentials (ERPs) can provide insight into cognitive processes, such as attention, working memory, and inhibitory control, that may influence the food-related decisions we make on a daily basis. We conducted a systematic review of the food-related cognition and ERP research in order to summarize the extant literature, identify future research questions, synthesize how food-related ERP components relate to eating habits and appetite, and demonstrate the utility of ERPs in examining food-related cognition. Forty-three articles were systematically extracted. In general, results indicated food cues compared to less palatable foods or neutral cues elicited greater ERP amplitudes reflecting early or late attention allocation (e.g., increased P2, P3, late positive potential amplitudes). Food cues were associated with increased frontocentral P3 and N2 ERP amplitudes compared to neutral or less palatable food cues, suggesting increased recruitment of inhibitory control and conflict monitoring resources. However, there was significant heterogeneity in the literature, as experimental tasks, stimuli, and examined ERP components varied widely across studies, and therefore replication studies are needed. In-depth research is also needed to establish how food-related ERPs differ by BMI groups and relate to real-world eating habits and appetite, in order to establish the ecological validity. Copyright © 2018. Published by Elsevier Ltd.

Time will tell: A longitudinal investigation of brain-behavior relationships during reading development

DOE PAGES

Stites, Mallory C.; Laszlo, Sarah

2017-02-23

ERPs are a powerful tool for the study of reading, as they are both temporally precise and functionally specific. These are essential characteristics for studying a process that unfolds rapidly and consists of multiple, interactive subprocesses. In work with adults, clear, specific models exist linking components of the ERP with individual subprocesses of reading including orthographic decoding, phonological processing, and semantic access (e.g., Grainger & Holcomb, 2009). The relationships between ERP components and reading subprocesses are less clear in development; here, we address two questions regarding these relationships. First, we ask whether there are ERP markers that predict future readingmore » behaviors across a longitudinal year. Second, we ask whether any relationships observed between ERP components and reading behavior across time map onto the better-established relationships between ERPs and reading subprocesses in adults. To address these questions, we acquired ERPs from children engaging in a silent reading task and then, a year later, collected behavioral assessments of their reading ability. Finally, we find that ERPs collected in Year 1 do predict reading behaviors a year later. Further, we find that these relationships do conform, at least to some extent, to relationships between ERP components and reading subprocesses observed in adults, with, for example, N250 amplitude in Year 1 predicting phonological awareness in Year 2, and N400 amplitude in Year 1 predicting vocabulary in Year 2.« less

Time will tell: A longitudinal investigation of brain-behavior relationships during reading development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stites, Mallory C.; Laszlo, Sarah

ERPs are a powerful tool for the study of reading, as they are both temporally precise and functionally specific. These are essential characteristics for studying a process that unfolds rapidly and consists of multiple, interactive subprocesses. In work with adults, clear, specific models exist linking components of the ERP with individual subprocesses of reading including orthographic decoding, phonological processing, and semantic access (e.g., Grainger & Holcomb, 2009). The relationships between ERP components and reading subprocesses are less clear in development; here, we address two questions regarding these relationships. First, we ask whether there are ERP markers that predict future readingmore » behaviors across a longitudinal year. Second, we ask whether any relationships observed between ERP components and reading behavior across time map onto the better-established relationships between ERPs and reading subprocesses in adults. To address these questions, we acquired ERPs from children engaging in a silent reading task and then, a year later, collected behavioral assessments of their reading ability. Finally, we find that ERPs collected in Year 1 do predict reading behaviors a year later. Further, we find that these relationships do conform, at least to some extent, to relationships between ERP components and reading subprocesses observed in adults, with, for example, N250 amplitude in Year 1 predicting phonological awareness in Year 2, and N400 amplitude in Year 1 predicting vocabulary in Year 2.« less

Combination of PCA and LORETA for sources analysis of ERP data: an emotional processing study

NASA Astrophysics Data System (ADS)

Hu, Jin; Tian, Jie; Yang, Lei; Pan, Xiaohong; Liu, Jiangang

2006-03-01

The purpose of this paper is to study spatiotemporal patterns of neuronal activity in emotional processing by analysis of ERP data. 108 pictures (categorized as positive, negative and neutral) were presented to 24 healthy, right-handed subjects while 128-channel EEG data were recorded. An analysis of two steps was applied to the ERP data. First, principal component analysis was performed to obtain significant ERP components. Then LORETA was applied to each component to localize their brain sources. The first six principal components were extracted, each of which showed different spatiotemporal patterns of neuronal activity. The results agree with other emotional study by fMRI or PET. The combination of PCA and LORETA can be used to analyze spatiotemporal patterns of ERP data in emotional processing.

Euclidean distance and Kolmogorov-Smirnov analyses of multi-day auditory event-related potentials: a longitudinal stability study

NASA Astrophysics Data System (ADS)

Durato, M. V.; Albano, A. M.; Rapp, P. E.; Nawang, S. A.

2015-06-01

The validity of ERPs as indices of stable neurophysiological traits is partially dependent on their stability over time. Previous studies on ERP stability, however, have reported diverse stability estimates despite using the same component scoring methods. This present study explores a novel approach in investigating the longitudinal stability of average ERPs—that is, by treating the ERP waveform as a time series and then applying Euclidean Distance and Kolmogorov-Smirnov analyses to evaluate the similarity or dissimilarity between the ERP time series of different sessions or run pairs. Nonlinear dynamical analysis show that in the absence of a change in medical condition, the average ERPs of healthy human adults are highly longitudinally stable—as evaluated by both the Euclidean distance and the Kolmogorov-Smirnov test.

Empirical models of scalp-EEG responses using non-concurrent intracranial responses

NASA Astrophysics Data System (ADS)

Kaur, Komalpreet; Shih, Jerry J.; Krusienski, Dean J.

2014-06-01

Objective. This study presents inter-subject models of scalp-recorded electroencephalographic (sEEG) event-related potentials (ERPs) using intracranially recorded ERPs from electrocorticography and stereotactic depth electrodes in the hippocampus, generally termed as intracranial EEG (iEEG). Approach. The participants were six patients with medically-intractable epilepsy that underwent temporary placement of intracranial electrode arrays to localize seizure foci. Participants performed one experimental session using a brain-computer interface matrix spelling paradigm controlled by sEEG prior to the iEEG electrode implantation, and one or more identical sessions controlled by iEEG after implantation. All participants were able to achieve excellent spelling accuracy using sEEG, four of the participants achieved roughly equivalent performance in the iEEG sessions, and all participants were significantly above chance accuracy for the iEEG sessions. The sERPs were modeled using a linear combination of iERPs using two different optimization criteria. Main results. The results indicate that sERPs can be accurately estimated from the iERPs for the patients that exhibited stable ERPs over the respective sessions, and that the transformed iERPs can be accurately classified with an sERP-derived classifier. Significance. The resulting models provide a new empirical representation of the formation and distribution of sERPs from underlying composite iERPs. These new insights provide a better understanding of ERP relationships and can potentially lead to the development of more robust signal processing methods for noninvasive EEG applications.

Tracking the dynamics of the social brain: ERP approaches for social cognitive and affective neuroscience

PubMed Central

Amodio, David M.; Ito, Tiffany A.

2014-01-01

Event-related potential (ERP) approaches to social cognitive and affective neuroscience (SCAN) are not as widely used as other neuroimaging techniques, yet they offer several unique advantages. In particular, the high temporal resolution of ERP measures of neural activity make them ideally suited for studying the dynamic interplay of rapidly unfolding cognitive and affective processes. In this article, we highlight the utility of ERP methods for scientists investigating questions of SCAN. We begin with a brief description of the physiological basis of ERPs and discussion of methodological practices. We then discuss how ERPs may be used to address a range of questions concerning social perception, social cognition, attitudes, affect and self-regulation, with examples of research that has used the ERP approach to contribute important theoretical advances in these areas. Whether used alone or in combination with other techniques, the ERP is an indispensable part of the social and affective neuroscientist’s methodological toolkit. PMID:24319116

Tracking the dynamics of the social brain: ERP approaches for social cognitive and affective neuroscience.

PubMed

Amodio, David M; Bartholow, Bruce D; Ito, Tiffany A

2014-03-01

Event-related potential (ERP) approaches to social cognitive and affective neuroscience (SCAN) are not as widely used as other neuroimaging techniques, yet they offer several unique advantages. In particular, the high temporal resolution of ERP measures of neural activity make them ideally suited for studying the dynamic interplay of rapidly unfolding cognitive and affective processes. In this article, we highlight the utility of ERP methods for scientists investigating questions of SCAN. We begin with a brief description of the physiological basis of ERPs and discussion of methodological practices. We then discuss how ERPs may be used to address a range of questions concerning social perception, social cognition, attitudes, affect and self-regulation, with examples of research that has used the ERP approach to contribute important theoretical advances in these areas. Whether used alone or in combination with other techniques, the ERP is an indispensable part of the social and affective neuroscientist's methodological toolkit.

Blunted neural responses to reward in remitted major depression: A high-density event-related potential study

PubMed Central

Whitton, Alexis E.; Kakani, Pragya; Foti, Dan; Van’t Veer, Ashlee; Haile, Anja; Crowley, David J.; Pizzagalli, Diego A.

2015-01-01

Background Major depressive disorder (MDD) is a highly recurrent condition, and improving our understanding of the abnormalities that persist in remitted MDD (rMDD) may provide insight into mechanisms that contribute to relapse. MDD has been characterized by reward learning deficits linked to dysfunction in frontostriatal regions. Although initial behavioral evidence of reward learning deficits in rMDD has recently emerged, it is unclear whether these reflect impairments in neural reward processing that persist into remission. Methods We examined behavioral reward learning and 128-channel event-related potentials (ERP) during a well-validated probabilistic reward task in 26 rMDD individuals and 34 never-depressed controls. Temporo-spatial principal components analysis (PCA) was used to separate overlapping ERP components, and group differences in neural activity in a priori regions were examined using low-resolution electromagnetic tomography (LORETA). Results Individuals with rMDD displayed reduced behavioral reward learning, as well as blunted ERP amplitude to reward feedback. Importantly, the reduction in ERP amplitude occurred at a PCA factor that peaked during the time at which phasic reward feedback-related signaling – hypothesized to originate in the striatum and project to the anterior cingulate cortex (ACC) – are thought to modulate scalp-recorded activity. Consistent with this, LORETA analyses revealed reduced activity in the ACC in the rMDD group, and this blunting correlated with poorer reward learning. Conclusion These findings suggest that the reward learning impairment observed in acute MDD persists into full remission and that these impairments may be attributable to abnormalities in the neural processes that support reward feedback monitoring, particularly within the ACC. PMID:26858994

Neural Basis of the Emotional Conflict Processing in Major Depression: ERPs and Source Localization Analysis on the N450 and P300 Components

PubMed Central

Zhu, Jing; Li, Jianxiu; Li, Xiaowei; Rao, Juan; Hao, Yanrong; Ding, Zhijie; Wang, Gangping

2018-01-01

Objects: Effective psychological function requires that cognition is not affected by task-irrelevant emotional stimuli in emotional conflict. Depression is mainly characterized as an emotional disorder. The object of this study is to reveal the behavioral and electrophysiological signature of emotional conflict processing in major depressive disorder (MDD) using event-related potentials (ERPs) and standardized low-resolution brain electromagnetic tomography (sLORETA) analysis. Method: We used a face–word Stroop task involving emotional faces while recording EEG (electroencephalography) in 20 patients with MDD and 20 healthy controls (HCs). And then ERPs were extracted and the corresponding brain sources were reconstructed using sLORETA. Results: Behaviorally, subjects with MDDs manifested significantly increased Stroop effect when examining the RT difference between happy incongruent trials and happy congruent trials, compared with HC subjects. ERP results exhibited that MDDs were characterized by the attenuated difference between P300 amplitude to sad congruent stimuli and sad incongruent stimuli, as electrophysiological evidence of impaired conflict processing in subjects with MDD. The sLORETA results showed that MDD patients had a higher current density in rostral anterior cingulate cortex (rostral ACC) within N450 time window in response to happy incongruent trials than happy congruent stimuli. Moreover, HC subjects had stronger activity in right inferior frontal gyrus (rIFG) region in response to incongruent stimuli than congruent stimuli, revealing successful inhibition of emotional distraction in HCs, which was absent in MDDs. Conclusion: Our results indicated that rostral ACC was implicated in the processing of negative emotional distraction in MDDs, as well as impaired inhibition of task-irrelevant emotional stimuli, relative to HCs. This work furnishes novel behavioral and neurophysiological evidence that are closely related to emotional conflict among MDD patients. PMID:29896094

Enhanced recovery protocol: implementation at a county institution with limited resources.

PubMed

Rona, Kais; Choi, J; Sigle, G; Kidd, S; Ault, G; Senagore, A J

2012-10-01

The benefits of an enhanced recovery protocol (ERP) in colorectal surgery have been well described; however, data on the implementation process is minimal, especially in a resource-limited institution. The purpose of this study was to evaluate outcomes during implementation of a physician-driven ERP at a public-funded institution. We retrospectively reviewed all elective colorectal surgery during a transition from standard care to an ERP (implemented via a standard order sheet). Data regarding use of care plan, length of stay (LOS), and rates of postoperative complications and readmission were recorded. One hundred eleven patients were included in the study; however, complete use of the ERP after its introduction occurred in a total of 50 patients for a compliance rate of 60 per cent (95% confidence interval [CI], 49 to 70). Late implementation of ERP diet, analgesics, and activity were the most common process errors. Full application of the ERP reduced mean LOS by 3 days (P=0.002), and there was a trend toward decreased postoperative morbidity without an increase in readmission rate (P=0.61). Full implementation of an ERP for colorectal surgery faces many challenges in a resource-limited county institution; however, when fully applied, the ERP safely reduced overall LOS, which is important in cost containment.

Combining features from ERP components in single-trial EEG for discriminating four-category visual objects.

PubMed

Wang, Changming; Xiong, Shi; Hu, Xiaoping; Yao, Li; Zhang, Jiacai

2012-10-01

Categorization of images containing visual objects can be successfully recognized using single-trial electroencephalograph (EEG) measured when subjects view images. Previous studies have shown that task-related information contained in event-related potential (ERP) components could discriminate two or three categories of object images. In this study, we investigated whether four categories of objects (human faces, buildings, cats and cars) could be mutually discriminated using single-trial EEG data. Here, the EEG waveforms acquired while subjects were viewing four categories of object images were segmented into several ERP components (P1, N1, P2a and P2b), and then Fisher linear discriminant analysis (Fisher-LDA) was used to classify EEG features extracted from ERP components. Firstly, we compared the classification results using features from single ERP components, and identified that the N1 component achieved the highest classification accuracies. Secondly, we discriminated four categories of objects using combining features from multiple ERP components, and showed that combination of ERP components improved four-category classification accuracies by utilizing the complementarity of discriminative information in ERP components. These findings confirmed that four categories of object images could be discriminated with single-trial EEG and could direct us to select effective EEG features for classifying visual objects.

ERPs and Psychopathology. I. Behavioral process issues.

PubMed

Roth, W T; Tecce, J J; Pfefferbaum, A; Rosenbloom, M; Callaway, E

1984-01-01

The clinical study of ERPs has an inherent defect--a self-selection of clinical populations that hampers equating of clinically defined groups on factors extraneous to the independent variables. Such ex post facto studies increase the likelihood of confounding variables in the interpretation of findings. Hence, the development of lawful relationships between clinical variables and ERPs is impeded and the fulfillment of description, explanation, prediction, and control in brain science is thwarted. Proper methodologies and theory development can increase the likelihood of establishing these lawful relationships. One methodology of potential value in the clinical application of ERPs, particularly in studies of aging, is that of divided attention. Two promising theoretical developments in the understanding of brain functioning and aging are the distraction-arousal hypothesis and the controlled-automatic attention model. The evaluation of ERPs in the study of brain-behavior relations in clinical populations might be facilitated by the differentiation of concurrent, predictive, content, and construct validities.

Electrophysiological Signals of Familiarity and Recency in the Infant Brain

ERIC Educational Resources Information Center

Snyder, Kelly A.; Garza, John; Zolot, Liza; Kresse, Anna

2010-01-01

Electrophysiological work in nonhuman primates has established the existence of multiple types of signals in the temporal lobe that contribute to recognition memory, including information regarding a stimulus's relative novelty, familiarity, and recency of occurrence. We used high-density event-related potentials (ERPs) to examine whether young…

About Turn: How Object Orientation Affects Categorisation and Mental Rotation

ERIC Educational Resources Information Center

Milivojevic, Branka; Hamm, Jeff P.; Corballis, Michael C.

2011-01-01

High-density ERPs evoked by rotated alphanumeric characters were examined to determine how neural processing is affected by stimulus orientation during letter/digit classifications and during mirror/normal discriminations. The former task typically produces response times that are unaffected by stimulus orientation while the latter is thought to…

Face-elicited ERPs and affective attitude: brain electric microstate and tomography analyses.

PubMed

Pizzagalli, D; Lehmann, D; Koenig, T; Regard, M; Pascual-Marqui, R D

2000-03-01

Although behavioral studies have demonstrated that normative affective traits modulate the processing of facial and emotionally charged stimuli, direct electrophysiological evidence for this modulation is still lacking. Event-related potential (ERP) data associated with personal, traitlike approach- or withdrawal-related attitude (assessed post-recording and 14 months later) were investigated in 18 subjects during task-free (i.e. unrequested, spontaneous) emotional evaluation of faces. Temporal and spatial aspects of 27 channel ERP were analyzed with microstate analysis and low resolution electromagnetic tomography (LORETA), a new method to compute 3 dimensional cortical current density implemented in the Talairach brain atlas. Microstate analysis showed group differences 132-196 and 196-272 ms poststimulus, with right-shifted electric gravity centers for subjects with negative affective attitude. During these (over subjects reliably identifiable) personality-modulated, face-elicited microstates, LORETA revealed activation of bilateral occipito-temporal regions, reportedly associated with facial configuration extraction processes. Negative compared to positive affective attitude showed higher activity right temporal; positive compared to negative attitude showed higher activity left temporo-parieto-occipital. These temporal and spatial aspects suggest that the subject groups differed in brain activity at early, automatic, stimulus-related face processing steps when structural face encoding (configuration extraction) occurs. In sum, the brain functional microstates associated with affect-related personality features modulate brain mechanisms during face processing already at early information processing stages.

Predicting perceptual learning from higher-order cortical processing.

PubMed

Wang, Fang; Huang, Jing; Lv, Yaping; Ma, Xiaoli; Yang, Bin; Wang, Encong; Du, Boqi; Li, Wu; Song, Yan

2016-01-01

Visual perceptual learning has been shown to be highly specific to the retinotopic location and attributes of the trained stimulus. Recent psychophysical studies suggest that these specificities, which have been associated with early retinotopic visual cortex, may in fact not be inherent in perceptual learning and could be related to higher-order brain functions. Here we provide direct electrophysiological evidence in support of this proposition. In a series of event-related potential (ERP) experiments, we recorded high-density electroencephalography (EEG) from human adults over the course of learning in a texture discrimination task (TDT). The results consistently showed that the earliest C1 component (68-84ms), known to reflect V1 activity driven by feedforward inputs, was not modulated by learning regardless of whether the behavioral improvement is location specific or not. In contrast, two later posterior ERP components (posterior P1 and P160-350) over the occipital cortex and one anterior ERP component (anterior P160-350) over the prefrontal cortex were progressively modified day by day. Moreover, the change of the anterior component was closely correlated with improved behavioral performance on a daily basis. Consistent with recent psychophysical and imaging observations, our results indicate that perceptual learning can mainly involve changes in higher-level visual cortex as well as in the neural networks responsible for cognitive functions such as attention and decision making. Copyright © 2015 Elsevier Inc. All rights reserved.

Spatiotemporal dynamics of the hedonic processing of chocolate images in individuals with and without trait chocolate craving.

PubMed

Asmaro, Deyar; Jaspers-Fayer, Fern; Sramko, Valery; Taake, Isabel; Carolan, Patrick; Liotti, Mario

2012-06-01

The spatiotemporal dynamics of the hedonic response to chocolate images was investigated in healthy participants high and low in trait-chocolate craving employing high-density ERPs. There were two sessions: (1) before and (2) after satiety for chocolate. Among cravers, chocolate stimuli evoked a positive amplitude ERP enhancement over the anterior frontal scalp (250-350 ms) that was not modified by satiety and that source localized to the left lateral orbitofrontal cortex. Chocolate stimuli also elicited a later LPP over the posterior scalp (360-560 ms) which was of similar amplitude for high and low chocolate cravers, independent of satiety. Unexpectedly, in non-cravers, chocolate stimuli elicited an earlier (100-250 ms) negative ERP modulation over the frontomedial scalp, which disappeared after eating chocolate to satiety. These results confirm the role of OFC in unrestrained appetitive responses to chocolate in cravers, and suggest top-down influences from cognitive control mechanisms when attempting to restrain the urge to eat chocolate in non-cravers. Copyright © 2012 Elsevier Ltd. All rights reserved.

Seven years follow-up of early repolarisation patterns in French elite special forces.

PubMed

Roche, Nicolas-Charles; Massoure, Pierre-Laurent; Deharo, Jean-Claude; Paule, Philippe; Fourcade, Laurent

2018-06-01

The early repolarization pattern (ERP) may be a marker of increased risk for sudden cardiac death (SCD). Influence of ethnicity on the ERP has not been extensively studied. The aim of this study was to evaluate the epidemiology of ERP in a male multiethnic population. ECG analysis was performed among consecutive recruits from the French Foreign Legion. ERP was characterized by a J-point elevation ≥0.1 mV in two continuous inferior-lateral leads, and high amplitude early repolarization (HAER-potentially malignant pattern) by an elevation ≥0.2 mV. Ethnical affiliation and level of physical activity were recorded. A total of 2508 healthy men (24 ± 5 years old) from 105 different native countries were divided into three ethnic groups: 1689 Whites, 388 Afro-Caribbean, and 431 Asians. ERP was found in 489 recruits (19%), 14% in Whites, 33% in Afro-Caribbeans, and 27% in Asians without any difference according to age and physical activity. Sub-Saharan Africans or Caribbeans had the highest rate of ERP (30%), and Hispanics the lowest (8%). People from occidental countries, Middle East, Central Asia or India had a rate of 12%-18%, East and South-Asia 20%-25%. Madagascar was an exception with only 16% of ERP. HAER (2.9%) was more frequent among Asian recruits. After 5 ± 2 years of follow up, one SCD occurred in the ERP group (p = 0.042). This study reports a large multiethnic analysis of ERP. HAER was more frequent in recruits from East and South-East Asia where sudden unexplained nocturnal death syndrome is endemic. © 2018 Wiley Periodicals, Inc.

Does the therapy manual or the therapist matter most in treatment of obsessive-compulsive disorder? A randomized controlled trial of exposure with response or ritual prevention in 118 patients.

PubMed

van Oppen, Patricia; van Balkom, Anton J L M; Smit, Johannes H; Schuurmans, Josien; van Dyck, Richard; Emmelkamp, Paul M G

2010-09-01

The importance of the therapist's education and experience for the successful behavior treatment of obsessive-compulsive disorder (OCD) has not been investigated. Data on the relative effectiveness of self-controlled versus therapist-controlled in vivo exposure with response or ritual prevention (ERP) have yielded conflicting results. The present study compared the effectiveness of 4 different modes of delivery of ERP in a referred sample of OCD patients. Of the 146 eligible OCD outpatients, 118 patients enrolled in this randomized controlled trial and were randomly assigned to (1) therapist-controlled ERP performed by experienced behavior therapists; (2) therapist-controlled ERP performed by master's students of clinical psychology; (3) self-controlled ERP performed by experienced behavior therapists; and (4) self-controlled ERP performed by master's students of clinical psychology. This trial was performed from January 1999 to January 2005. Our analyses revealed no significant differences in clinical outcome between any of the different modes of delivery of ERP at posttreatment. The different ERP modes of delivery were associated with significant pretreatment to posttreatment improvement on all measurements, with large effect sizes on the primary outcome measure, the Yale-Brown Obsessive Compulsive Scale. Our results indicate that clinically inexperienced master's students with no postgraduate training can be as capable as experienced and certified behavior therapists in treating OCD patients, as long as therapists adhere to a standardized treatment manual and adequate training and supervision is provided. In contrast to other studies, we did not find a supposed benefit of therapist-controlled ERP versus self-controlled ERP in patients with OCD. www.trialregister.nl Identifier: NTR1444. © Copyright 2010 Physicians Postgraduate Press, Inc.

Enterprise resource planning (ERP) implementation using the value engineering methodology and Six Sigma tools

NASA Astrophysics Data System (ADS)

Leu, Jun-Der; Lee, Larry Jung-Hsing

2017-09-01

Enterprise resource planning (ERP) is a software solution that integrates the operational processes of the business functions of an enterprise. However, implementing ERP systems is a complex process. In addition to the technical issues, companies must address problems associated with business process re-engineering, time and budget control, and organisational change. Numerous industrial studies have shown that the failure rate of ERP implementation is high, even for well-designed systems. Thus, ERP projects typically require a clear methodology to support the project execution and effectiveness. In this study, we propose a theoretical model for ERP implementation. The value engineering (VE) method forms the basis of the proposed framework, which integrates Six Sigma tools. The proposed framework encompasses five phases: knowledge generation, analysis, creation, development and execution. In the VE method, potential ERP problems related to software, hardware, consultation and organisation are analysed in a group-decision manner and in relation to value, and Six Sigma tools are applied to avoid any project defects. We validate the feasibility of the proposed model by applying it to an international manufacturing enterprise in Taiwan. The results show improvements in customer response time and operational efficiency in terms of work-in-process and turnover of materials. Based on the evidence from the case study, the theoretical framework is discussed together with the study's limitations and suggestions for future research.

ERP implementation in hospitals: a case study.

PubMed

Agarwal, Divya; Garg, Poonam

2012-01-01

In a competitive healthcare sector, hospitals have to focus on their processes in order to deliver high-quality care while at the same time reducing costs. Many hospitals have decided to adopt one or another Enterprise Resource Planning (ERP) system to improve their businesses, but implementing an ERP system can be a demanding endeavour. The systems are so difficult to implement that some are successful; many have failed, causing multimillion dollar losses. The challenge of ERP solutions lie in implementation because they are complex, time consuming and expensive too. This paper describes the various process workflows and phases of ERP implementation at Fortis Hospital Cunningham Road, Bangalore, India. This knowledge will provide valuable insights for the researchers and practitioners to understand the different process workflows and to make informed decisions when implementing ERP in any hospital.

Amplitude modulation of steady-state visual evoked potentials by event-related potentials in a working memory task

PubMed Central

Yao, Dezhong; Tang, Yu; Huang, Yilan; Su, Sheng

2009-01-01

Previous studies have shown that the amplitude and phase of the steady-state visual-evoked potential (SSVEP) can be influenced by a cognitive task, yet the mechanism of this influence has not been understood. As the event-related potential (ERP) is the direct neural electric response to a cognitive task, studying the relationship between the SSVEP and ERP would be meaningful in understanding this underlying mechanism. In this work, the traditional average method was applied to extract the ERP directly, following the stimulus of a working memory task, while a technique named steady-state probe topography was utilized to estimate the SSVEP under the simultaneous stimulus of an 8.3-Hz flicker and a working memory task; a comparison between the ERP and SSVEP was completed. The results show that the ERP can modulate the SSVEP amplitude, and for regions where both SSVEP and ERP are strong, the modulation depth is large. PMID:19960240

Event-related potentials, cognition, and behavior: a biological approach.

PubMed

Kotchoubey, Boris

2006-01-01

The prevailing cognitive-psychological accounts of event-related brain potentials (ERPs) assume that ERP components manifest information processing operations leading from stimulus to response. Since this view encounters numerous difficulties already analyzed in previous studies, an alternative view is presented here that regards cortical control of behavior as a repetitive sensorimotor cycle consisting of two phases: (i) feedforward anticipation and (ii) feedback cortical performance. This view allows us to interpret in an integrative manner numerous data obtained from very different domains of ERP studies: from biophysics of ERP waves to their relationship to the processing of language, in which verbal behavior is viewed as likewise controlled by the same two basic control processes: feedforward (hypothesis building) and feedback (hypothesis checking). The proposed approach is intentionally simplified, explaining numerous effects on the basis of few assumptions and relating several levels of analysis: neurophysiology, macroelectrical processes (i.e. ERPs), cognition and behavior. It can, therefore, be regarded as a first approximation to a general theory of ERPs.

Implementation of an enhanced recovery protocol in pediatric colorectal surgery.

PubMed

Short, Heather L; Heiss, Kurt F; Burch, Katelyn; Travers, Curtis; Edney, John; Venable, Claudia; Raval, Mehul V

2018-04-01

Enhanced recovery protocols (ERPs) have been shown to improve outcomes in adult surgical populations. Our purpose was to compare outcomes before and after implementation of an ERP in children undergoing elective colorectal surgery. A pediatric-specific colorectal ERP was developed and implemented at a single center starting in January 2015. A retrospective review was performed including 43 patients in the pre-ERP period (2012-2014) and 36 patients in the post-ERP period (2015-2016). Outcomes of interest included number of ERP interventions received, length of stay (LOS), complications, and readmissions. The median number of ERP interventions received per patient increased from 5 to 11 from 2012 to 2016. The median LOS decreased from 5days to 3days in the post-ERP period (p=0.01). We observed a simultaneous decrease in median time to regular diet, mean dose of narcotics, and mean volume of intraoperative fluids (p<0.001). The complication rate (21% vs. 17%, p=0.85) and 30-day readmission rate (23% vs. 11%, p=0.63) were not significantly different in the pre- and post-ERP periods. Implementation of a pediatric-specific ERP in children undergoing colorectal surgery is feasible, safe and may lead to improved outcomes. Further experience may highlight other opportunities for increased compliance and improved care. Treatment Study. Level III. Copyright © 2017 Elsevier Inc. All rights reserved.

ERPS to Monitor Non-conscious Mentation

NASA Technical Reports Server (NTRS)

Donchin, E.

1984-01-01

Event Related Brain Potentials (or ERPs) are extracted from the EEG that can be recorded between a pair of electrodes placed on a person's scalp. The EEG is recorded as a continual fluctuation in voltage. It is the results of the integration of the potential fields generated by a multitude of neuronal ensembles that are active as the brain goes about its business. Within this ongoing signal it is possible to distinguish voltage fluctuations that are triggered in neural structures by the occurrence of specific events. This activity, evoked as it is by an external event, is known as the Evoked, or Event Related, Potential. The ERPs provide a unique opportunity to monitor non-conscious mentation. The inferences that can be based on ERP data are described and the limits of these inferences are emphasized. This, however, will not be an exhaustive review of the use of ERPs in Engineering Psychology. The application, its scope, and its limitations will be illustrated by means of one example. This example is preceded by a brief technical introduction to the methodology used in the study of ERPs. The manner in which ERPs are used to study cognition is described.

Auditory evoked potentials in patients with major depressive disorder measured by Emotiv system.

PubMed

Wang, Dongcui; Mo, Fongming; Zhang, Yangde; Yang, Chao; Liu, Jun; Chen, Zhencheng; Zhao, Jinfeng

2015-01-01

In a previous study (unpublished), Emotiv headset was validated for capturing event-related potentials (ERPs) from normal subjects. In the present follow-up study, the signal quality of Emotiv headset was tested by the accuracy rate of discriminating Major Depressive Disorder (MDD) patients from the normal subjects. ERPs of 22 MDD patients and 15 normal subjects were induced by an auditory oddball task and the amplitude of N1, N2 and P3 of ERP components were specifically analyzed. The features of ERPs were statistically investigated. It is found that Emotiv headset is capable of discriminating the abnormal N1, N2 and P3 components in MDD patients. Relief-F algorithm was applied to all features for feature selection. The selected features were then input to a linear discriminant analysis (LDA) classifier with leave-one-out cross-validation to characterize the ERP features of MDD. 127 possible combinations out of the selected 7 ERP features were classified using LDA. The best classification accuracy was achieved to be 89.66%. These results suggest that MDD patients are identifiable from normal subjects by ERPs measured by Emotiv headset.

How L2-Learners' Brains React to Code-Switches: An ERP Study with Russian Learners of German

ERIC Educational Resources Information Center

Ruigendijk, Esther; Hentschel, Gerd; Zeller, Jan Patrick

2016-01-01

This Event Related Potentials (ERP) study investigates auditory processing of sentences with so-called code-switches in Russian learners of German. It has often been argued that switching between two languages results in extra processing cost, although it is not completely clear yet what exactly causes these costs. ERP presents a good method to…

Towards a holistic assessment of the user experience with hybrid BCIs.

PubMed

Lorenz, Romy; Pascual, Javier; Blankertz, Benjamin; Vidaurre, Carmen

2014-06-01

In recent years, brain-computer interfaces (BCIs) have become mature enough to immensely benefit from the expertise and tools established in the field of human-computer interaction (HCI). One of the core objectives in HCI research is the design of systems that provide a pleasurable user experience (UX). While the majority of BCI studies exclusively evaluate common efficiency measures such as classification accuracy and speed, single research groups have begun to look at further usability aspects such as ease of use, workload and learnability. However, these evaluation metrics only cover pragmatic aspects of UX while still not considering the hedonic quality of UX. In order to gain a holistic perspective on UX, hedonic quality aspects such as motivation and frustration were also taken into account for our evaluation of three BCI-driven interfaces, which were proposed to be used as a two-stage neuroprosthetic control within the EU project MUNDUS. At the first stage, one of six possible actions was selected and either confirmed or cancelled at the second stage. For the experiment, a solely event-related-potential-based interface (ERP-ERP) and two hybrid solutions were tested that were controlled by ERP and motor imagery (MI)--resulting in the two possible combinations: ERP selection/MI confirmation (ERP-MI) or MI selection/ERP confirmation (MI-ERP). Behavioural, subjective and encephalographic (EEG) data of 12 healthy subjects were collected during an online experiment with the three graphical user interfaces (GUIs). Results showed a significantly greater pragmatic quality (in terms of accuracy, efficiency, workload, use quality and learnability) for the ERP-ERP and ERP-MI GUIs in contrast to the MI-ERP GUI. Consequently, the MI-ERP GUI is least suited for use as a neuroprosthetic control. With respect to the comparison of the ERP-ERP and ERP-MI GUIs, no significant differences in pragmatic and hedonic quality of UX were found. Since throughout better results were obtained for the conventional approach and it was most preferred by the subjects, the ERP-ERP GUI seems more suitable for its deployment in actual end-users. Nevertheless, for individuals with stable MI patterns, the hybrid interface can be provided as an additional option of choice within the MUNDUS framework. Although the paramount goal in BCI research still remains the improvement of classification accuracy and communication speed, it is of significance to note that it is equally important for end-users to keep up their motivation and prevent frustration. By including pragmatic as well as hedonic quality aspects, this study is the first effort to gain a holistic perspective of the UX while interacting with BCI-driven assistive technology aimed at actual end-users. The broad-scale methodology provided valuable insights into the underlying dynamics causing the users' experience to differ across the GUIs. The results will be used to refine a BCI-driven neuroprosthesis and test it with end-users.

Towards a holistic assessment of the user experience with hybrid BCIs

NASA Astrophysics Data System (ADS)

Lorenz, Romy; Pascual, Javier; Blankertz, Benjamin; Vidaurre, Carmen

2014-06-01

Objective. In recent years, brain-computer interfaces (BCIs) have become mature enough to immensely benefit from the expertise and tools established in the field of human-computer interaction (HCI). One of the core objectives in HCI research is the design of systems that provide a pleasurable user experience (UX). While the majority of BCI studies exclusively evaluate common efficiency measures such as classification accuracy and speed, single research groups have begun to look at further usability aspects such as ease of use, workload and learnability. However, these evaluation metrics only cover pragmatic aspects of UX while still not considering the hedonic quality of UX. In order to gain a holistic perspective on UX, hedonic quality aspects such as motivation and frustration were also taken into account for our evaluation of three BCI-driven interfaces, which were proposed to be used as a two-stage neuroprosthetic control within the EU project MUNDUS. Approach. At the first stage, one of six possible actions was selected and either confirmed or cancelled at the second stage. For the experiment, a solely event-related-potential-based interface (ERP-ERP) and two hybrid solutions were tested that were controlled by ERP and motor imagery (MI)—resulting in the two possible combinations: ERP selection/MI confirmation (ERP-MI) or MI selection/ERP confirmation (MI-ERP). Behavioural, subjective and encephalographic (EEG) data of 12 healthy subjects were collected during an online experiment with the three graphical user interfaces (GUIs). Main results. Results showed a significantly greater pragmatic quality (in terms of accuracy, efficiency, workload, use quality and learnability) for the ERP-ERP and ERP-MI GUIs in contrast to the MI-ERP GUI. Consequently, the MI-ERP GUI is least suited for use as a neuroprosthetic control. With respect to the comparison of the ERP-ERP and ERP-MI GUIs, no significant differences in pragmatic and hedonic quality of UX were found. Since throughout better results were obtained for the conventional approach and it was most preferred by the subjects, the ERP-ERP GUI seems more suitable for its deployment in actual end-users. Nevertheless, for individuals with stable MI patterns, the hybrid interface can be provided as an additional option of choice within the MUNDUS framework. Significance. Although the paramount goal in BCI research still remains the improvement of classification accuracy and communication speed, it is of significance to note that it is equally important for end-users to keep up their motivation and prevent frustration. By including pragmatic as well as hedonic quality aspects, this study is the first effort to gain a holistic perspective of the UX while interacting with BCI-driven assistive technology aimed at actual end-users. The broad-scale methodology provided valuable insights into the underlying dynamics causing the users’ experience to differ across the GUIs. The results will be used to refine a BCI-driven neuroprosthesis and test it with end-users.

Bootstrap Signal-to-Noise Confidence Intervals: An Objective Method for Subject Exclusion and Quality Control in ERP Studies

PubMed Central

Parks, Nathan A.; Gannon, Matthew A.; Long, Stephanie M.; Young, Madeleine E.

2016-01-01

Analysis of event-related potential (ERP) data includes several steps to ensure that ERPs meet an appropriate level of signal quality. One such step, subject exclusion, rejects subject data if ERP waveforms fail to meet an appropriate level of signal quality. Subject exclusion is an important quality control step in the ERP analysis pipeline as it ensures that statistical inference is based only upon those subjects exhibiting clear evoked brain responses. This critical quality control step is most often performed simply through visual inspection of subject-level ERPs by investigators. Such an approach is qualitative, subjective, and susceptible to investigator bias, as there are no standards as to what constitutes an ERP of sufficient signal quality. Here, we describe a standardized and objective method for quantifying waveform quality in individual subjects and establishing criteria for subject exclusion. The approach uses bootstrap resampling of ERP waveforms (from a pool of all available trials) to compute a signal-to-noise ratio confidence interval (SNR-CI) for individual subject waveforms. The lower bound of this SNR-CI (SNRLB) yields an effective and objective measure of signal quality as it ensures that ERP waveforms statistically exceed a desired signal-to-noise criterion. SNRLB provides a quantifiable metric of individual subject ERP quality and eliminates the need for subjective evaluation of waveform quality by the investigator. We detail the SNR-CI methodology, establish the efficacy of employing this approach with Monte Carlo simulations, and demonstrate its utility in practice when applied to ERP datasets. PMID:26903849

Knowledge Management ERP Curriculum Design/Mapping (Theory and Development Tools)

ERIC Educational Resources Information Center

Swanson, Zane; Hepner, Michelle

2011-01-01

This study proposes a knowledge management framework for developing and managing enterprise resource planning (ERP) curriculum within business schools. Both theory and a practical implementation are addressed. The knowledge management (KM) framework has two components which utilize ERP from a big picture curriculum overview and a ground level…

Spatiotemporal Dynamics of Speech Sound Perception in Chronic Developmental Stuttering

ERIC Educational Resources Information Center

Liotti, Mario; Ingham, Janis C.; Takai, Osamu; Paskos, Delia Kothmann; Perez, Ricardo; Ingham, Roger J.

2010-01-01

High-density ERPs were recorded in eight adults with persistent developmental stuttering (PERS) and eight matched normally fluent (CONT) control volunteers while participants either repeatedly uttered the vowel "ah" or listened to their own previously recorded vocalizations. The fronto-central N1 auditory wave was reduced in response to spoken…

Assessing ERP SAP implementation in the small and medium enterprises (SMEs) in Indonesia

NASA Astrophysics Data System (ADS)

Yohannes; Gunawan, W.; Ikhsan, R. B.; Aries

2018-03-01

The consistent growth of Indonesian SMEs has received attention of global IT vendors. One of major ERP player in Indonesian market such as SAP, has introduced ERP solutions for SMEs through SAP Business One. Due to its fast growth, unfortunately, there are still very few articles can be found to understand the ERP implementation in Indonesian SMEs. The article addressed the common factors that affect the successful of the ERP implementation at SMEs. They are: identifying vendor quality, opening balance data migration, and A-SAP methodology. The article applied case study method to examine the fast growth companies owned by same owners, such as: GRK, MMM, and KM25; with the objectives to identify the practical pattern of ERP implementation in SMEs that will be useful for SAP project manager and consultants.

Probe-evoked event-related potential techniques for evaluating aspects of attention and information processing

NASA Technical Reports Server (NTRS)

Stern, John A.

1988-01-01

The study of probe event related potentials (probe ERPs) is reviewed. Several recent experiments are described which seem to leave in doubt the usefulness of applying ERP to simulation and field conditions as well as laboratory situations. Relatively minor changes in the experimental paradigm can produce major shifts in ERP findings, for reasons that are not clear. However, task-elicited ERPs might be used on a flight simulator if the experimenter takes time of arrival of the eyes on a particular instrument as one variable of concern and dwell time on the instrument as a second variable. One can then look at ERPs triggered by saccade termination for fixation pauses of specified durations. It may well be that ERP to a momentarily important display will differ from that elicited by routine instrument check.

A Comparative Analysis of Strategic Approaches for Information Technology (IT) Management for Commander Naval Surface Forces

DTIC Science & Technology

2010-03-01

29 d. Coca Cola Case Study .............................................................31 3. Outsourcing...Electric, Coca - Cola , Hershey Foods, International Business Machines Corporation (IBM), and BP/Amoco (Lousek, 2000). c. Disadvantages of ERP ERP...look at all aspects of the organization to determine if the value added is worth the cost of implementing an ERP system. d. Coca Cola Case Study

Neuronal generator patterns at scalp elicited by lateralized aversive pictures reveal consecutive stages of motivated attention

PubMed Central

Kayser, Jürgen; Tenke, Craig E.; Abraham, Karen S.; Alschuler, Daniel M.; Alvarenga, Jorge E.; Skipper, Jamie; Warner, Virginia; Bruder, Gerard E.; Weissman, Myrna M.

2016-01-01

Event-related potential (ERP) studies have provided evidence for an allocation of attentional resources to enhance perceptual processing of motivationally salient stimuli. Emotional modulation affects several consecutive components associated with stages of affective-cognitive processing, beginning as early as 100-200 ms after stimulus onset. In agreement with the notion that the right parietotemporal region is critically involved during the perception of arousing affective stimuli, some ERP studies have reported asymmetric emotional ERP effects. However, it is difficult to separate emotional from non-emotional effects because differences in stimulus content unrelated to affective salience or task demands may also be associated with lateralized function or promote cognitive processing. Other concerns pertain to the operational definition and statistical independence of ERP component measures, their dependence on an EEG reference, and spatial smearing due to volume conduction, all of which impede the identification of distinct scalp activation patterns associated with affective processing. Building on prior research using a visual half-field paradigm with highly-controlled emotional stimuli (pictures of cosmetic surgery patients showing disordered [negative] or healed [neutral] facial areas before or after treatment), 72-channel ERPs recorded from 152 individuals (age 13-68 years; 81 female) were transformed into reference-free current source density (CSD) waveforms and submitted to temporal principal components analysis (PCA) to identify their underlying neuronal generator patterns. Using both nonparametric randomization tests and repeated measures ANOVA, robust effects of emotional content were found over parietooccipital regions for CSD factors corresponding to N2 sink (212 ms peak latency), P3 source (385 ms) and a late centroparietal source (630 ms), all indicative of greater positivity for negative than neutral stimuli. For the N2 sink, emotional effects were right-lateralized and modulated by hemifield, with larger amplitude and asymmetry for left hemifield (right hemisphere) presentations. For all three factors, more positive amplitudes at parietooccipital sites were associated with increased ratings of negative valence and greater arousal. Distributed inverse solutions of the CSD-PCA-based emotional effects implicated a sequence of maximal activations in right occipitotemporal cortex, bilateral posterior cingulate cortex, and bilateral inferior temporal cortex. These findings are consistent with hierarchical activations of the ventral visual pathway reflecting subsequent processing stages in response to motivationally salient stimuli. PMID:27263509

Neuronal generator patterns at scalp elicited by lateralized aversive pictures reveal consecutive stages of motivated attention.

PubMed

Kayser, Jürgen; Tenke, Craig E; Abraham, Karen S; Alschuler, Daniel M; Alvarenga, Jorge E; Skipper, Jamie; Warner, Virginia; Bruder, Gerard E; Weissman, Myrna M

2016-11-15

Event-related potential (ERP) studies have provided evidence for an allocation of attentional resources to enhance perceptual processing of motivationally salient stimuli. Emotional modulation affects several consecutive components associated with stages of affective-cognitive processing, beginning as early as 100-200ms after stimulus onset. In agreement with the notion that the right parietotemporal region is critically involved during the perception of arousing affective stimuli, some ERP studies have reported asymmetric emotional ERP effects. However, it is difficult to separate emotional from non-emotional effects because differences in stimulus content unrelated to affective salience or task demands may also be associated with lateralized function or promote cognitive processing. Other concerns pertain to the operational definition and statistical independence of ERP component measures, their dependence on an EEG reference, and spatial smearing due to volume conduction, all of which impede the identification of distinct scalp activation patterns associated with affective processing. Building on prior research using a visual half-field paradigm with highly controlled emotional stimuli (pictures of cosmetic surgery patients showing disordered [negative] or healed [neutral] facial areas before or after treatment), 72-channel ERPs recorded from 152 individuals (ages 13-68years; 81 female) were transformed into reference-free current source density (CSD) waveforms and submitted to temporal principal components analysis (PCA) to identify their underlying neuronal generator patterns. Using both nonparametric randomization tests and repeated measures ANOVA, robust effects of emotional content were found over parietooccipital regions for CSD factors corresponding to N2 sink (212ms peak latency), P3 source (385ms) and a late centroparietal source (630ms), all indicative of greater positivity for negative than neutral stimuli. For the N2 sink, emotional effects were right-lateralized and modulated by hemifield, with larger amplitude and asymmetry for left hemifield (right hemisphere) presentations. For all three factors, more positive amplitudes at parietooccipital sites were associated with increased ratings of negative valence and greater arousal. Distributed inverse solutions of the CSD-PCA-based emotional effects implicated a sequence of maximal activations in right occipitotemporal cortex, bilateral posterior cingulate cortex, and bilateral inferior temporal cortex. These findings are consistent with hierarchical activations of the ventral visual pathway reflecting subsequent processing stages in response to motivationally salient stimuli. Copyright © 2016 Elsevier Inc. All rights reserved.

Auditory Evoked Potentials as a Function of Sleep Deprivation and Recovery Sleep

DTIC Science & Technology

1985-09-29

present research: They relate to the effects of: a) 48-hours of sleep deprivation on endogenous event related potentials (ERPs); b) circadian rhythms on...the study were: decreases in amplitude for N2, P3 and N2P3 across the reprivation period; a circadian rhythm was apparent for both ERP recordings and...of cortical evoked response potentials (ERPs)? 2) How do circadian rhythms affect ERPS under conditions of sleep deprivation? 3) How do different

ERP System Implementation: An Oil and Gas Exploration Sector Perspective

NASA Astrophysics Data System (ADS)

Mishra, Alok; Mishra, Deepti

Enterprise Resource Planning (ERP) systems provide integration and optimization of various business processes which leads to improved planning and decision quality, smoother coordination between business units resulting in higher efficiency, and quicker response time to customer demands and inquiries. This paper reports challenges, opportunities and outcome of ERP implementation in Oil & Gas exploration sector. This study will facilitate in understanding transition, constraints and implementation of ERP in this sector and also provide guidelines from lessons learned in this regard.

ERp29 controls invasion and metastasis of gastric carcinoma by inhibition of epithelial-mesenchymal transition via PI3K/Aktsignaling pathway.

PubMed

Ye, Jianxin; Huang, Jinsheng; Xu, Jie; Huang, Qiang; Wang, Jinzhou; Zhong, Wenjing; Lin, Xinjian; Li, Yun; Lin, Xu

2017-09-06

Gastric cancer (GC) accounts for the fourth most occurring malignancy and the third major cause of cancer death. Identifying novel molecular signaling pathways participating in gastric tumorigenesis and progression is pivotal for rational design of targeted therapies to improve advanced GC outcome. Recently, the endoplasmic reticulum (ER) protein 29 (ERp29) has been shown to inversely associate with primary tumor development and function as a tumor suppressor in breast cancer. However, the role of ERp29 in GC patients' prognosis and its function in GC progression is unknown. Clinical importance of ERp29 in the prognosis of GC patients was assessed by examining its expression in 148 GC tumor samples and correlation with clinicopathological characteristics and survival of the patients. The function and underlying mechanisms of ERp29 in GC growth, invasion and metastasis were explored both in vitro and in vivo. Downregulation of ERp29 was commonly found in GC tissues and highly correlated with more aggressive phenotypes and poorer prognosis. Functional assays demonstrated that knockdown of ERp29 increased GC cell migration and invasion and promoted metastasis. Conversely, ectopic overexpression of ERp29 produced opposite effects. Mechanistic studies revealed that loss of ERp29 induced an epithelial-to-mesenchymal transition (EMT) in the GC cells through activation of PI3K/Akt pathway signaling. These findings suggest that downregulation of ERp29 is probably one of the key molecular mechanisms responsible for the development and progression of GC.

Investigation of the mediating effects of IT governance-value delivery on service quality and ERP performance

NASA Astrophysics Data System (ADS)

Tsai, Wen-Hsien; Chou, Yu-Wei; Leu, Jun-Der; Chao Chen, Der; Tsaur, Tsen-Shu

2015-02-01

This study aimed to explore the mediating effects of IT governance (ITG)-value delivery in the relationships among the quality of vendor service, the quality of consultant services, ITG-value delivery and enterprise resource planning (ERP) performance. The sampling of this research was acquired from a questionnaire survey concerning ERP implementations in Taiwan. In this survey, 4366 questionnaires were sent to manufacturing and service companies listed in the TOP 5000: The Largest Corporations in Taiwan 2009. The results showed that an ERP system will exhibit a decreased error rate and improved performance if ERP system vendors and consultants provide good service quality. The results also demonstrated that significant relationships exist among the quality of vendor service, the quality of consultant services and value delivery. The contribution of this article is twofold. First, it found that value delivery provides an effective measure of ERP performance under an ITG framework. Second, it provides evidence of the partial mediating effects of value delivery between service quality and ERP performance. In other words, if enterprises want to improve ERP performance, they need to consider factors such as value delivery and the quality of a vendor/consultant's service.

Implementation of false discovery rate for exploring novel paradigms and trait dimensions with ERPs.

PubMed

Crowley, Michael J; Wu, Jia; McCreary, Scott; Miller, Kelly; Mayes, Linda C

2012-01-01

False discovery rate (FDR) is a multiple comparison procedure that targets the expected proportion of false discoveries among the discoveries. Employing FDR methods in event-related potential (ERP) research provides an approach to explore new ERP paradigms and ERP-psychological trait/behavior relations. In Study 1, we examined neural responses to escape behavior from an aversive noise. In Study 2, we correlated a relatively unexplored trait dimension, ostracism, with neural response. In both situations we focused on the frontal cortical region, applying a channel by time plots to display statistically significant uncorrected data and FDR corrected data, controlling for multiple comparisons.

Gender differences in the processing of standard emotional visual stimuli: integrating ERP and fMRI results

NASA Astrophysics Data System (ADS)

Yang, Lei; Tian, Jie; Wang, Xiaoxiang; Hu, Jin

2005-04-01

The comprehensive understanding of human emotion processing needs consideration both in the spatial distribution and the temporal sequencing of neural activity. The aim of our work is to identify brain regions involved in emotional recognition as well as to follow the time sequence in the millisecond-range resolution. The effect of activation upon visual stimuli in different gender by International Affective Picture System (IAPS) has been examined. Hemodynamic and electrophysiological responses were measured in the same subjects. Both fMRI and ERP study were employed in an event-related study. fMRI have been obtained with 3.0 T Siemens Magnetom whole-body MRI scanner. 128-channel ERP data were recorded using an EGI system. ERP is sensitive to millisecond changes in mental activity, but the source localization and timing is limited by the ill-posed 'inversed' problem. We try to investigate the ERP source reconstruction problem in this study using fMRI constraint. We chose ICA as a pre-processing step of ERP source reconstruction to exclude the artifacts and provide a prior estimate of the number of dipoles. The results indicate that male and female show differences in neural mechanism during emotion visual stimuli.

Ten years on: a follow-up review of ERP research in attention-deficit/hyperactivity disorder.

PubMed

Johnstone, Stuart J; Barry, Robert J; Clarke, Adam R

2013-04-01

This article reviews the event-related potential (ERP) literature in relation to attention-deficit/hyperactivity disorder (AD/HD) over the years 2002-2012. ERP studies exploring various aspects of brain functioning in children and adolescents with AD/HD are reviewed, with a focus on group effects and interpretations in the domains of attention, inhibitory control, performance monitoring, non-pharmacological treatments, and ERP/energetics interactions. There has been a distinct shift in research intensity over the past 10 years, with a large increase in ERP studies conducted in the areas of inhibitory control and performance monitoring. Overall, the research has identified a substantial number of ERP correlates of AD/HD. Robust differences from healthy controls have been reported in early orienting, inhibitory control, and error-processing components. These data offer potential to improve our understanding of the specific brain dysfunction(s) which contribute to the disorder. The literature would benefit from a more rigorous approach to clinical group composition and consideration of age effects, as well as increased emphasis on replication and extension studies using exacting participant, task, and analysis parameters. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Electrophysiological Correlates of Impaired Reading in Dyslexic Pre-Adolescent Children

ERIC Educational Resources Information Center

Araujo, Susana; Bramao, Ines; Faisca, Luis; Petersson, Karl Magnus; Reis, Alexandra

2012-01-01

In this study, event related potentials (ERPs) were used to investigate the extent to which dyslexics (aged 9-13 years) differ from normally reading controls in early ERPs, which reflect prelexical orthographic processing, and in late ERPs, which reflect implicit phonological processing. The participants performed an implicit reading task, which…

Improving Training in Enterprise Resource Planning Systems Implementation through Communities of Practice

ERIC Educational Resources Information Center

Kerr, Don; Burgess, Kevin J.; Houghton, Luke; Murray, Peter A.

2012-01-01

The Enterprise Resource Planning (ERP) literature suggests that effective training is one of the key reasons for success in ERP implementations. However, limited research has been conducted on what constitutes effective training in an ERP environment. A case study approach was used to explore the effectiveness of traditional training and to…

Does ERP Hands-On Experience Help Students Learning Business Process Concepts?

ERIC Educational Resources Information Center

Rienzo, Thomas; Han, Bernard

2011-01-01

Over the past decade, more and more business schools are attempting to teach business processes (BPs) by using enterprise resource planning (ERP) software in their curricula. Currently, most studies involving ERP software in the academy have concentrated on learning and teaching via self-assessment surveys or curriculum integration. This research…

University ERP Implementation in Germany: Qualitative Exploratory Case Study of Administrative Staff Experiences

ERIC Educational Resources Information Center

Thelen, Anja

2015-01-01

Enterprise Resource Planning (ERP) implementations are expensive, time-consuming, and often do not lead to the expected outcome of integrated IT systems. Many German universities are implementing ERP systems as Campus Management Systems (CMS) and a solution to any problem, need, or requirement the organization has. This exploratory case study…

Gender Differences in Memory Processing: Evidence from Event-Related Potentials to Faces

ERIC Educational Resources Information Center

Guillem, F.; Mograss, M.

2005-01-01

This study investigated gender differences on memory processing using event-related potentials (ERPs). Behavioral data and ERPs were recorded in 16 males and 10 females during a recognition memory task for faces. The behavioral data results showed that females performed better than males. Gender differences on ERPs were evidenced over anterior…

Attention-dependent sound offset-related brain potentials.

PubMed

Horváth, János

2016-05-01

When performing sensory tasks, knowing the potentially occurring goal-relevant and irrelevant stimulus events allows the establishment of selective attention sets, which result in enhanced sensory processing of goal-relevant events. In the auditory modality, such enhancements are reflected in the increased amplitude of the N1 ERP elicited by the onsets of task-relevant sounds. It has been recently suggested that ERPs to task-relevant sound offsets are similarly enhanced in a tone-focused state in comparison to a distracted one. The goal of the present study was to explore the influence of attention on ERPs elicited by sound offsets. ERPs elicited by tones in a duration-discrimination task were compared to ERPs elicited by the same tones in not-tone-focused attentional setting. Tone offsets elicited a consistent, attention-dependent biphasic (positive-negative--P1-N1) ERP waveform for tone durations ranging from 150 to 450 ms. The evidence, however, did not support the notion that the offset-related ERPs reflected an offset-specific attention set: The offset-related ERPs elicited in a duration-discrimination condition (in which offsets were task relevant) did not significantly differ from those elicited in a pitch-discrimination condition (in which the offsets were task irrelevant). Although an N2 reflecting the processing of offsets in task-related terms contributed to the observed waveform, this contribution was separable from the offset-related P1 and N1. The results demonstrate that when tones are attended, offset-related ERPs may substantially overlap endogenous ERP activity in the postoffset interval irrespective of tone duration, and attention differences may cause ERP differences in such postoffset intervals. © 2016 Society for Psychophysiological Research.

The disulfide isomerase ERp57 is required for fibrin deposition in vivo.

PubMed

Zhou, J; Wu, Y; Wang, L; Rauova, L; Hayes, V M; Poncz, M; Essex, D W

2014-11-01

ERp57 is required for platelet function; however, whether ERp57 contributes to fibrin generation is unknown. Using an inhibitory anti-ERp57 antibody (mAb1), Pf4-Cre/ERp57(fl/fl) mice, Tie2-Cre/ERp57(fl/fl) mice, and mutants of ERp57, we analyzed the function of ERp57 in laser-induced thrombosis. Fibrin deposition was decreased in Pf4-Cre/ERp57(fl/fl) mice, consistent with a role for platelet ERp57 in fibrin generation. Fibrin deposition was further decreased with infusion of mAb1 and in Tie2-Cre/ERp57(fl/fl) mice, consistent with endothelial cells also contributing to fibrin deposition. Infusion of eptibifatide inhibited platelet and fibrin deposition, confirming a role for platelets in fibrin deposition. Infusion of recombinant ERp57 corrected the defect in fibrin deposition but not platelet accumulation, suggesting a direct effect of ERp57 on coagulation. mAb1 inhibited thrombin generation in vitro, consistent with a requirement for ERp57 in coagulation. Platelet accumulation was decreased to similar extents in Pf4-Cre/ERp57(fl/fl) mice, Tie2-Cre/ERp57(fl/fl) mice and normal mice infused with mAb1. Infusion of completely inactivated ERp57 or ERp57 with a non-functional second active site inhibited fibrin deposition and platelet accumulation, indicating that the isomerase activity of the second active site is required for these processes. ERp57 regulates thrombosis via multiple targets. © 2014 International Society on Thrombosis and Haemostasis.

Method of evaluating the impact of ERP implementation critical success factors - a case study in oil and gas industries

NASA Astrophysics Data System (ADS)

Gajic, Gordana; Stankovski, Stevan; Ostojic, Gordana; Tesic, Zdravko; Miladinovic, Ljubomir

2014-01-01

The so far implemented enterprise resource planning (ERP) systems have in many cases failed to meet the requirements regarding the business process control, decrease of business costs and increase of company profit margin. Therefore, there is a real need for an evaluation of the influence of ERP on the company's performance indicators. Proposed in this article is an advanced model for the evaluation of the success of ERP implementation on organisational and operational performance indicators in oil-gas companies. The recommended method establishes a correlation between a process-based method, a scorecard model and ERP critical success factors. The method was verified and tested on two case studies in oil-gas companies using the following procedure: the model was developed, tested and implemented in a pilot gas-oil company, while the results were implemented and verified in another gas-oil company.

Crystal structures of the Erp protein family members ErpP and ErpC from Borrelia burgdorferi reveal the reason for different affinities for complement regulator factor H.

PubMed

Brangulis, Kalvis; Petrovskis, Ivars; Kazaks, Andris; Akopjana, Inara; Tars, Kaspars

2015-05-01

Borrelia burgdorferi is the causative agent of Lyme disease, which can be acquired after the bite of an infected Ixodes tick. As a strategy to resist the innate immunity and to successfully spread and proliferate, B. burgdorferi expresses a set of outer membrane proteins that are capable of binding complement regulator factor H (CFH), factor H-like protein 1 (CFHL-1) and factor H-related proteins (CFHR) to avoid complement-mediated killing. B. burgdorferi B31 contains three proteins that belong to the Erp (OspE/F-related) protein family and are capable of binding CFH and some CFHRs, namely ErpA, ErpC and ErpP. We have determined the crystal structure of ErpP at 2.53Å resolution and the crystal structure of ErpC at 2.15Å resolution. Recently, the crystal structure of the Erp family member OspE from B. burgdorferi N40 was determined in complex with CFH domains 19-20, revealing the residues involved in the complex formation. Despite the high sequence conservation between ErpA, ErpC, ErpP and the homologous protein OspE (78-80%), the affinity for CFH and CFHRs differs markedly among the Erp family members, suggesting that ErpC may bind only CFHRs but not CFH. A comparison of the binding site in OspE with those of ErpC and ErpP revealed that the extended loop region, which is only observed in the potential binding site of ErpC, plays an important role by preventing the binding of CFH. These results can explain the inability of ErpC to bind CFH, whereas ErpP and ErpA still possess the ability to bind CFH. Copyright © 2015 Elsevier B.V. All rights reserved.

Neurophysiological evidence for a recollection impairment in amnesia patients that leaves familiarity intact

PubMed Central

Addante, Richard J.; Ranganath, Charan; Olichney, John; Yonelinas, Andrew P.

2012-01-01

In several previous behavioral studies, we have identified a group of amnestic patients that, behaviorally, appear to exhibit severe deficits in recollection with relative preservation of familiarity-based recognition. However, these studies have relied exclusively on behavioral measures, rather than direct measures of physiology. Event-related potentials (ERPs) have been used to identify putative neural correlates of familiarity- and recollection-based recognition memory, but little work has been done to determine the extent to which these ERP correlates are spared in patients with relatively specific memory disorders. ERP studies of recognition in healthy subjects have indicated that recollection and familiarity are related to a parietal old-new effect characterized as a late positive component (LPC) and an earlier mid-frontal old-new effect referred to as an ‘FN400’, respectively. Here, we sought to determine the extent to which the putative ERP correlates of recollection and familiarity are intact or impaired in these patients. We recorded ERPs in three amnestic patients and six age matched controls while they made item recognition and source recognition judgments. The current patients were able to discriminate between old and new items fairly well, but showed nearly chance-level performance at source recognition. Moreover, whereas control subjects exhibited ERP correlates of memory that have been linked to recollection and familiarity, the patients only exhibited the mid-frontal FN400 ERP effect related to familiarity-based recognition. The results show that recollection can be severely impaired in amnesia even when familiarity-related processing is relatively spared, and they also provide further evidence that ERPs can be used to distinguish between neural correlates of familiarity and recollection. PMID:22898646

Adapted wavelet transform improves time-frequency representations: a study of auditory elicited P300-like event-related potentials in rats.

PubMed

Richard, Nelly; Laursen, Bettina; Grupe, Morten; Drewes, Asbjørn M; Graversen, Carina; Sørensen, Helge B D; Bastlund, Jesper F

2017-04-01

Active auditory oddball paradigms are simple tone discrimination tasks used to study the P300 deflection of event-related potentials (ERPs). These ERPs may be quantified by time-frequency analysis. As auditory stimuli cause early high frequency and late low frequency ERP oscillations, the continuous wavelet transform (CWT) is often chosen for decomposition due to its multi-resolution properties. However, as the conventional CWT traditionally applies only one mother wavelet to represent the entire spectrum, the time-frequency resolution is not optimal across all scales. To account for this, we developed and validated a novel method specifically refined to analyse P300-like ERPs in rats. An adapted CWT (aCWT) was implemented to preserve high time-frequency resolution across all scales by commissioning of multiple wavelets operating at different scales. First, decomposition of simulated ERPs was illustrated using the classical CWT and the aCWT. Next, the two methods were applied to EEG recordings obtained from prefrontal cortex in rats performing a two-tone auditory discrimination task. While only early ERP frequency changes between responses to target and non-target tones were detected by the CWT, both early and late changes were successfully described with strong accuracy by the aCWT in rat ERPs. Increased frontal gamma power and phase synchrony was observed particularly within theta and gamma frequency bands during deviant tones. The study suggests superior performance of the aCWT over the CWT in terms of detailed quantification of time-frequency properties of ERPs. Our methodological investigation indicates that accurate and complete assessment of time-frequency components of short-time neural signals is feasible with the novel analysis approach which may be advantageous for characterisation of several types of evoked potentials in particularly rodents.

Electrophysiological evidence for the modulation of retrieval orientation by depth of study processing.

PubMed

Rugg, M D; Allan, K; Birch, C S

2000-07-01

Event-related potentials (ERPs) were employed to investigate whether brain activity elicited by retrieval cues in a memory test varies according to the encoding task undertaken at study. Two recognition memory test blocks were administered, preceded, in one case, by a "shallow" study task (alphabetic judgement) and, in the other case, by a "deep" task (sentence generation). ERPs elicited by the new words in each test block differed, the ERPs elicited in the block following the shallow study task exhibiting the more positive-going waveforms. This finding was taken as evidence that subjects adopt different "retrieval sets" when attempting to retrieve items that had been encoded in terms of alphabetic versus semantic attributes. Differences between the ERPs elicited by correctly classified old and new words (old/new effects) also varied with encoding task. The effects for deeply studied words resembled those found in previous ERP studies of recognition memory, whereas old/new effects for shallowly studied words were confined to a late-onsetting, right frontal positivity. Together, the findings indicate that the depth of study processing influences two kinds of memory-related neural activity, associated with memory search operations, and the processing of retrieved information, respectively.

Case study of open-source enterprise resource planning implementation in a small business

NASA Astrophysics Data System (ADS)

Olson, David L.; Staley, Jesse

2012-02-01

Enterprise resource planning (ERP) systems have been recognised as offering great benefit to some organisations, although they are expensive and problematic to implement. The cost and risk make well-developed proprietorial systems unaffordable to small businesses. Open-source software (OSS) has become a viable means of producing ERP system products. The question this paper addresses is the feasibility of OSS ERP systems for small businesses. A case is reported involving two efforts to implement freely distributed ERP software products in a small US make-to-order engineering firm. The case emphasises the potential of freely distributed ERP systems, as well as some of the hurdles involved in their implementation. The paper briefly reviews highlights of OSS ERP systems, with the primary focus on reporting the case experiences for efforts to implement ERPLite software and xTuple software. While both systems worked from a technical perspective, both failed due to economic factors. While these economic conditions led to imperfect results, the case demonstrates the feasibility of OSS ERP for small businesses. Both experiences are evaluated in terms of risk dimension.

The oxidoreductase ERp57 efficiently reduces partially folded in preference to fully folded MHC class I molecules

PubMed Central

Antoniou, Antony N.; Ford, Stuart; Alphey, Magnus; Osborne, Andrew; Elliott, Tim; Powis, Simon J.

2002-01-01

The oxidoreductase ERp57 is an integral component of the peptide loading complex of major histocompatibility complex (MHC) class I molecules, formed during their chaperone-assisted assembly in the endoplasmic reticulum. Misfolded MHC class I molecules or those denied suitable peptides are retrotranslocated and degraded in the cytosol. The presence of ERp57 during class I assembly suggests it may be involved in the reduction of intrachain disulfides prior to retrotranslocation. We have studied the ability of ERp57 to reduce MHC class I molecules in vitro. Recombinant ERp57 specifically reduced partially folded MHC class I molecules, whereas it had little or no effect on folded and peptide-loaded MHC class I molecules. Reductase activity was associated with cysteines at positions 56 and 405 of ERp57, the N-terminal residues of the active CXXC motifs. Our data suggest that the reductase activity of ERp57 may be involved during the unfolding of MHC class I molecules, leading to targeting for degradation. PMID:12032078

The interoperability force in the ERP field

NASA Astrophysics Data System (ADS)

Boza, Andrés; Cuenca, Llanos; Poler, Raúl; Michaelides, Zenon

2015-04-01

Enterprise resource planning (ERP) systems participate in interoperability projects and this participation sometimes leads to new proposals for the ERP field. The aim of this paper is to identify the role that interoperability plays in the evolution of ERP systems. To go about this, ERP systems have been first identified within interoperability frameworks. Second, the initiatives in the ERP field driven by interoperability requirements have been identified from two perspectives: technological and business. The ERP field is evolving from classical ERP as information system integrators to a new generation of fully interoperable ERP. Interoperability is changing the way of running business, and ERP systems are changing to adapt to the current stream of interoperability.

ERp57 interacts with conserved cysteine residues in the MHC class I peptide-binding groove.

PubMed

Antoniou, Antony N; Santos, Susana G; Campbell, Elaine C; Lynch, Sarah; Arosa, Fernando A; Powis, Simon J

2007-05-15

The oxidoreductase ERp57 is a component of the major histocompatibility complex (MHC) class I peptide-loading complex. ERp57 can interact directly with MHC class I molecules, however, little is known about which of the cysteine residues within the MHC class I molecule are relevant to this interaction. MHC class I molecules possess conserved disulfide bonds between cysteines 101-164, and 203-259 in the peptide-binding and alpha3 domain, respectively. By studying a series of mutants of these conserved residues, we demonstrate that ERp57 predominantly associates with cysteine residues in the peptide-binding domain, thus indicating ERp57 has direct access to the peptide-binding groove of MHC class I molecules during assembly.

Implementation of enhanced recovery programme after pancreatoduodenectomy: a single-centre UK pilot study.

PubMed

Abu Hilal, Mohammed; Di Fabio, Francesco; Badran, Abdallah; Alsaati, Hani; Clarke, Hannah; Fecher, Imogen; Armstrong, Thomas H; Johnson, Colin D; Pearce, Neil W

2013-01-01

Data on enhanced recovery programmes after pancreatoduodenectomy (ERP-PD) is limited. The aim of this pilot study was to evaluate the feasibility, safety and clinical outcomes of ERP-PD when implemented at a high-volume UK university referral centre. This was an observational single-surgeon case-control study (before-and-after pathway). A total of 20 consecutive patients were prospectively enrolled for the ERP-PD and compared with 24 consecutive patients previously treated during an equal time frame. Patients in the ERP-PD group had a significant shorter time to remove naso-gastric tube (median of 5 vs. 7 days, p = 0.0001), start liquid diet (median of 2 vs. 5 days, p < 0.0001), start solid food (median of 4 vs. 9 days, p < 0.0001), pass stools (median of 6 vs. 7 days, p = 0.002), and had shorter length of stay (median of 8.5 days vs. 13 days, p = 0.015) compared to the pre-pathway group. Postoperative complications were overall less frequent but not significantly different in the ERP-PD group (p = 0.077). No difference in mortality and readmission rates was found. Our findings support the feasibility and safety of ERP-PD. Improved patients' outcomes, significant bed day savings and increase National Health Service productivity are anticipated with implementation of ERP-PD on a larger scale. Copyright © 2012 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Proposing a New Framework and an Innovative Approach to Teaching Reengineering and ERP Implementation Concepts

ERIC Educational Resources Information Center

Pellerin, Robert; Hadaya, Pierre

2008-01-01

Recognizing the need to teach ERP implementation and business process reengineering (BPR) concepts simultaneously, as well as the pedagogical limitations of the case teaching method and simulation tools, the objective of this study is to propose a new framework and an innovative teaching approach to improve the ERP training experience for IS…

Inadequate and Infrequent Are Not Alike: ERPs to Deviant Prosodic Patterns in Spoken Sentence Comprehension

ERIC Educational Resources Information Center

Mietz, Anja; Toepel, Ulrike; Ischebeck, Anja; Alter, Kai

2008-01-01

The current study on German investigates Event-Related brain Potentials (ERPs) for the perception of sentences with intonations which are infrequent (i.e. vocatives) or inadequate in daily conversation. These ERPs are compared to the processing correlates for sentences in which the syntax-to-prosody relations are congruent and used frequently…

Development of Action Monitoring through Adolescence into Adulthood: ERP and Source Localization

ERIC Educational Resources Information Center

Ladouceur, Cecile D.; Dahl, Ronald E.; Carter, Cameron S.

2007-01-01

In this study we examined the development of three action monitoring event-related potentials (ERPs)--the error-related negativity (ERN/Ne), error positivity (P[subscript E]) and the N2--and estimated their neural sources. These ERPs were recorded during a flanker task in the following groups: early adolescents (mean age = 12 years), late…

Neural Correlates of Encoding Predict Infants' Memory in the Paired-Comparison Procedure

ERIC Educational Resources Information Center

Snyder, Kelly A.

2010-01-01

The present study used event-related potentials (ERPs) to monitor infant brain activity during the initial encoding of a previously novel visual stimulus, and examined whether ERP measures of encoding predicted infants' subsequent performance on a visual memory task (i.e., the paired-comparison task). A late slow wave component of the ERP measured…

Action Monitoring Cortical Activity Coupled to Submovements

PubMed Central

Sobolewski, Aleksander

2017-01-01

Numerous studies have examined neural correlates of the human brain’s action-monitoring system during experimentally segmented tasks. However, it remains unknown how such a system operates during continuous motor output when no experimental time marker is available (such as button presses or stimulus onset). We set out to investigate the electrophysiological correlates of action monitoring when hand position has to be repeatedly monitored and corrected. For this, we recorded high-density electroencephalography (EEG) during a visuomotor tracking task during which participants had to follow a target with the mouse cursor along a visible trajectory. By decomposing hand kinematics into naturally occurring periodic submovements, we found an event-related potential (ERP) time-locked to these submovements and localized in a sensorimotor cortical network comprising the supplementary motor area (SMA) and the precentral gyrus. Critically, the amplitude of the ERP correlated with the deviation of the cursor, 110 ms before the submovement. Control analyses showed that this correlation was truly due to the cursor deviation and not to differences in submovement kinematics or to the visual content of the task. The ERP closely resembled those found in response to mismatch events in typical cognitive neuroscience experiments. Our results demonstrate the existence of a cortical process in the SMA, evaluating hand position in synchrony with submovements. These findings suggest a functional role of submovements in a sensorimotor loop of periodic monitoring and correction and generalize previous results from the field of action monitoring to cases where action has to be repeatedly monitored. PMID:29071301

A Roadmap for the Development and Validation of ERP Biomarkers in Schizophrenia Research

PubMed Central

Luck, Steven J.; Mathalon, Daniel H.; O'Donnell, Brian F.; Hämäläinen, Matti S.; Spencer, Kevin M.; Javitt, Daniel C.; Uhlhaas, Peter J.

2010-01-01

New efforts to develop treatments for cognitive dysfunction in mental illnesses would benefit enormously from biomarkers that provide sensitive and reliable measures of the neural events underlying cognition. Here we evaluate the promise of event-related potentials (ERPs) as biomarkers of cognitive dysfunction in schizophrenia. We conclude that ERPs have several desirable properties: (a) they provide a direct measure of electrical activity during neurotransmission; (b) their high temporal resolutions makes it possible to measure neural synchrony and oscillations; (c) they are relatively inexpensive and convenient to record; (d) animal models are readily available for several ERP components; (e) decades of research has established the sensitivity and reliability of ERP measures in psychiatric illnesses; and (f) feasibility of large N (>500) multi-site studies has been demonstrated for key measures. Consequently, ERPs may be useful for identifying endophenotypes and defining treatment targets, for evaluating new compounds in animals and in humans, and for identifying individuals who are good candidates for early interventions or for specific treatments. However, several challenges must be overcome before ERPs gain widespread use as biomarkers in schizophrenia research, and we make several recommendations for the research that is necessary to develop and validate ERP-based biomarkers that can have a real impact on treatment development. PMID:21111401

Dimension reduction: additional benefit of an optimal filter for independent component analysis to extract event-related potentials.

PubMed

Cong, Fengyu; Leppänen, Paavo H T; Astikainen, Piia; Hämäläinen, Jarmo; Hietanen, Jari K; Ristaniemi, Tapani

2011-09-30

The present study addresses benefits of a linear optimal filter (OF) for independent component analysis (ICA) in extracting brain event-related potentials (ERPs). A filter such as the digital filter is usually considered as a denoising tool. Actually, in filtering ERP recordings by an OF, the ERP' topography should not be changed by the filter, and the output should also be able to be modeled by the linear transformation. Moreover, an OF designed for a specific ERP source or component may remove noise, as well as reduce the overlap of sources and even reject some non-targeted sources in the ERP recordings. The OF can thus accomplish both the denoising and dimension reduction (reducing the number of sources) simultaneously. We demonstrated these effects using two datasets, one containing visual and the other auditory ERPs. The results showed that the method including OF and ICA extracted much more reliable components than the sole ICA without OF did, and that OF removed some non-targeted sources and made the underdetermined model of EEG recordings approach to the determined one. Thus, we suggest designing an OF based on the properties of an ERP to filter recordings before using ICA decomposition to extract the targeted ERP component. Copyright © 2011 Elsevier B.V. All rights reserved.

A graphical user interface for infant ERP analysis.

PubMed

Kaatiala, Jussi; Yrttiaho, Santeri; Forssman, Linda; Perdue, Katherine; Leppänen, Jukka

2014-09-01

Recording of event-related potentials (ERPs) is one of the best-suited technologies for examining brain function in human infants. Yet the existing software packages are not optimized for the unique requirements of analyzing artifact-prone ERP data from infants. We developed a new graphical user interface that enables an efficient implementation of a two-stage approach to the analysis of infant ERPs. In the first stage, video records of infant behavior are synchronized with ERPs at the level of individual trials to reject epochs with noncompliant behavior and other artifacts. In the second stage, the interface calls MATLAB and EEGLAB (Delorme & Makeig, Journal of Neuroscience Methods 134(1):9-21, 2004) functions for further preprocessing of the ERP signal itself (i.e., filtering, artifact removal, interpolation, and rereferencing). Finally, methods are included for data visualization and analysis by using bootstrapped group averages. Analyses of simulated and real EEG data demonstrated that the proposed approach can be effectively used to establish task compliance, remove various types of artifacts, and perform representative visualizations and statistical comparisons of ERPs. The interface is available for download from http://www.uta.fi/med/icl/methods/eeg.html in a format that is widely applicable to ERP studies with special populations and open for further editing by users.

Using ERPs to Investigate Valence Processing in the Affect Misattribution Procedure

PubMed Central

Von Gunten, Curtis D.; Bartholow, Bruce D.; Scherer, Laura D.

2016-01-01

The construct validity of the Affect Misattribution Procedure (AMP) has been challenged by theories proposing that the task does not actually measure affect misattribution. The current study tested the validity of the AMP as a measure of affect misattribution by examining three components of the event-related potential (ERP) known to be associated with the allocation of motivated attention. Results revealed that ERP amplitudes varied in response to affectively ambiguous targets as a function of the valence of preceding primes. Furthermore, differences in ERP responses to the targets were largely similar to differences in ERPs elicited by the primes. The existence of valence differentiation in both the prime-locked and the target-locked ERPs, along with the similarity in this differentiation, provides evidence that the affective content of the primes is psychologically registered, and that this content influences the processing of the subsequent, evaluatively ambiguous targets, both of which are required if the priming effects found in the AMP are the result of affect misattribution. However, the behavioral priming effect was uncorrelated with ERP amplitudes, leaving some question as to the locus of this effect in the information-processing system. Findings are discussed in light of the strengths and weaknesses of using ERPs to understand the priming effects in the AMP. PMID:27754548

Neurophysiological Effects of Meditation Based on Evoked and Event Related Potential Recordings

PubMed Central

Singh, Nilkamal; Telles, Shirley

2015-01-01

Evoked potentials (EPs) are a relatively noninvasive method to assess the integrity of sensory pathways. As the neural generators for most of the components are relatively well worked out, EPs have been used to understand the changes occurring during meditation. Event-related potentials (ERPs) yield useful information about the response to tasks, usually assessing attention. A brief review of the literature yielded eleven studies on EPs and seventeen on ERPs from 1978 to 2014. The EP studies covered short, mid, and long latency EPs, using both auditory and visual modalities. ERP studies reported the effects of meditation on tasks such as the auditory oddball paradigm, the attentional blink task, mismatched negativity, and affective picture viewing among others. Both EP and ERPs were recorded in several meditations detailed in the review. Maximum changes occurred in mid latency (auditory) EPs suggesting that maximum changes occur in the corresponding neural generators in the thalamus, thalamic radiations, and primary auditory cortical areas. ERP studies showed meditation can increase attention and enhance efficiency of brain resource allocation with greater emotional control. PMID:26137479

Neurophysiological Effects of Meditation Based on Evoked and Event Related Potential Recordings.

PubMed

Singh, Nilkamal; Telles, Shirley

2015-01-01

Evoked potentials (EPs) are a relatively noninvasive method to assess the integrity of sensory pathways. As the neural generators for most of the components are relatively well worked out, EPs have been used to understand the changes occurring during meditation. Event-related potentials (ERPs) yield useful information about the response to tasks, usually assessing attention. A brief review of the literature yielded eleven studies on EPs and seventeen on ERPs from 1978 to 2014. The EP studies covered short, mid, and long latency EPs, using both auditory and visual modalities. ERP studies reported the effects of meditation on tasks such as the auditory oddball paradigm, the attentional blink task, mismatched negativity, and affective picture viewing among others. Both EP and ERPs were recorded in several meditations detailed in the review. Maximum changes occurred in mid latency (auditory) EPs suggesting that maximum changes occur in the corresponding neural generators in the thalamus, thalamic radiations, and primary auditory cortical areas. ERP studies showed meditation can increase attention and enhance efficiency of brain resource allocation with greater emotional control.

Assessing the internal consistency of the event-related potential: An example analysis.

PubMed

Thigpen, Nina N; Kappenman, Emily S; Keil, Andreas

2017-01-01

ERPs are widely and increasingly used to address questions in psychophysiological research. As discussed in this special issue, a renewed focus on questions of reliability and stability marks the need for intuitive, quantitative descriptors that allow researchers to communicate the robustness of ERP measures used in a given study. This report argues that well-established indices of internal consistency and effect size meet this need and can be easily extracted from most ERP datasets, as demonstrated with example analyses using a representative dataset from a feature-based visual selective attention task. We demonstrate how to measure the internal consistency of three aspects commonly considered in ERP studies: voltage measurements for specific time ranges at selected sensors, voltage dynamics across all time points of the ERP waveform, and the distribution of voltages across the scalp. We illustrate methods for quantifying the robustness of experimental condition differences, by calculating effect size for different indices derived from the ERP. The number of trials contributing to the ERP waveform was manipulated to examine the relationship between signal-to-noise ratio (SNR), internal consistency, and effect size. In the present example dataset, satisfactory consistency (Cronbach's alpha > 0.7) of individual voltage measurements was reached at lower trial counts than were required to reach satisfactory effect sizes for differences between experimental conditions. Comparing different metrics of robustness, we conclude that the internal consistency and effect size of ERP findings greatly depend on the quantification strategy, the comparisons and analyses performed, and the SNR. © 2016 Society for Psychophysiological Research.

Assessing the internal consistency of the event-related potential: An example analysis

PubMed Central

Thigpen, Nina; Kappenman, Emily; Keil, Andreas

2017-01-01

Event-related potentials (ERPs) are widely and increasingly used to address questions in Psychophysiological research. As discussed in this special issue, a renewed focus on questions of reliability and stability marks the need for intuitive, quantitative descriptors that allow researchers to communicate the robustness of ERP measures used in a given study. This report argues that well-established indices of internal consistency and effect size meet this need and can be easily extracted from most ERP data sets, as demonstrated with example analyses using a representative data set from a feature-based visual selective attention task. We demonstrate how to measure the internal consistency of three aspects commonly considered in ERP studies: Voltage measurements for specific time ranges at selected sensors, voltage dynamics across all time points of the ERP waveform, and the distribution of voltages across the scalp. We illustrate methods for quantifying the robustness of experimental condition differences, by calculating effect size for different indices derived from the ERP. The number of trials contributing to the ERP waveform was manipulated to examine the relationship between signal-to-noise ratio, internal consistency, and effect size. In the present example data set, satisfactory consistency (Cronbach’s alpha > 0.7) of individual voltage measurements was reached at lower trial counts than were required to reach satisfactory effect sizes for differences between experimental conditions. Comparing different metrics of robustness, we conclude that the SNR, internal consistency, and effect size of ERP findings greatly depend on the quantification strategy, the comparisons and analyses performed, and the signal-to-noise ratio. PMID:28000264

Usability evaluation of in-housed developed ERP system

NASA Astrophysics Data System (ADS)

Faisal, Chaudhry Muhammad Nadeem; Shakeel Faridi, Muhammad; Javed, Zahid

2011-10-01

Enterprise Resource Planning systems are the combination of different business IS (Information System) applications that are designed according to the organization requirements. Generally ERP systems are suffering from complex user interface issues. Recent research shows that there is a need for improvement concerning, the user interface from their perspectives. In order to design the software applications that are easy to use, memorize and apply to new problems, we must know the users philosophy and something about learning, reminiscence and problems solving. The Usability engineering is the only way to study the deeds of users while interacting with ERP (Enterprise Resource & Planning). This paper will focus on the users' experiences view of financial module in ERP system. The HCI research method, explicitly survey questionnaire method was adopted to gather users understanding in order to evaluate the selected modules for in-housed ERP system. The study involved group of users from two industries, the results can not be generalized as a whole. The study was first time successfully applied Usability evaluation on in-housed ERP in local industry (Masood Textile Mills, Interloop Ltd) in Pakistan. The results may hopefully opened-up an area of research and methodology that could provide considerable further benefits to Industry in developments of Industrial information systems.

The Challenge of Implementing an ERP System in a Small and Medium Enterprise--A Teaching Case of ERP Project Management

ERIC Educational Resources Information Center

Xu, Hongjiang; Rondeau, Patrick J.; Mahenthiran, Sakthi

2011-01-01

Enterprise Resource Planning (ERP) system implementation projects are notoriously risky. While large-scale ERP cases continue to be developed, relatively few new ERP cases have been published that further ERP implementation education in small to medium size firms. This case details the implementation of a new ERP system in a medium sized…

Implementation of an Enhanced Recovery Pathway After Pancreaticoduodenectomy in Patients with Low Drain Fluid Amylase.

PubMed

Sutcliffe, Robert P; Hamoui, Majd; Isaac, John; Marudanayagam, Ravi; Mirza, Darius F; Muiesan, Paolo; Roberts, John K

2015-08-01

The safety and feasibility of an enhanced recovery pathway (ERP) after pancreatic surgery is largely unknown. Our aim was to prospectively evaluate a targeted ERP after pancreaticoduodenectomy (PD), using first postoperative day (POD) drain fluid amylase (DFA1) values to identify patients at low risk of pancreatic fistula (PF). Non-randomized cohort study of 130 consecutive patients. Perioperative outcomes were compared before (pre-ERP; N=65) and after (post-ERP; N=65) implementation of an ERP. Patients in each group were stratified according to the risk of PF using DFA1<350 IU/l. Low-risk patients in the post-ERP group were selected for early oral intake and early drain removal. 81/130 patients had a DFA1<350. Incidence of PF was significantly lower in low-risk patients (9 vs. 45%, P=0.0001). In low-risk patients, morbidity (43 vs. 36%) and mortality (2.7 vs. 4.5%) were similar for both pre- and post-ERP patients. Hospital stay (median 9 vs. 7 days, P=0.03) and 30-day readmissions (17 vs. 2%, P=0.04) were lower in low-risk patients in the post-ERP group. In high-risk patients, there was no difference in outcomes between pre- and post-ERP. Patients at low risk of PF after PD can be identified by first POD DFA1. Enhanced recovery after PD is safe and leads to improved short-term outcomes in low-risk patients.

Test-retest reliability of infant event related potentials evoked by faces.

PubMed

Munsters, N M; van Ravenswaaij, H; van den Boomen, C; Kemner, C

2017-04-05

Reliable measures are required to draw meaningful conclusions regarding developmental changes in longitudinal studies. Little is known, however, about the test-retest reliability of face-sensitive event related potentials (ERPs), a frequently used neural measure in infants. The aim of the current study is to investigate the test-retest reliability of ERPs typically evoked by faces in 9-10 month-old infants. The infants (N=31) were presented with neutral, fearful and happy faces that contained only the lower or higher spatial frequency information. They were tested twice within two weeks. The present results show that the test-retest reliability of the face-sensitive ERP components is moderate (P400 and Nc) to substantial (N290). However, there is low test-retest reliability for the effects of the specific experimental manipulations (i.e. emotion and spatial frequency) on the face-sensitive ERPs. To conclude, in infants the face-sensitive ERP components (i.e. N290, P400 and Nc) show adequate test-retest reliability, but not the effects of emotion and spatial frequency on these ERP components. We propose that further research focuses on investigating elements that might increase the test-retest reliability, as adequate test-retest reliability is necessary to draw meaningful conclusions on individual developmental trajectories of the face-sensitive ERPs in infants. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Overcoming Murphy`s Law to gain ERP - a case study at Gibbons Creek Lignite Mine, Texas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lancaster, E.M.; Horbaczewski, J.K.

1997-12-31

As of January 1997, there are 2,586 acres of reclaimed land in the Extended Responsibility Period (ERP) at Gibbons Creek Lignite Mine, Texas. This achievement has taken approximately five years to accomplish - from 1991 to 1996. During this period, there were a number of issues, some of which appeared to follow Murphy`s Law (whatever can go wrong, will go wrong!). For example, the ERP candidate areas were split among three permit areas, which first had to be consolidated to facilitate the ERP process. Minesoil issues, identified as ERP prerequisites, became entangled in an overall renewal/revision of the newly-consolidated Permitmore » 26B. Special-purpose vegetation studies were performed to investigate the effects of different minesoil textures. In the meantime, small depressional areas, wetland/wildlife enhancement areas, reclamation ponds and restored drainages became the subjects of attention from landowners and regulatory agencies. Some of these structures and features were subsequently reclaimed; others were approved via the permitting process. In some cases, the only way out of the impasse was through land acquisition. Finally, after all these issues had been resolved, an unforeseen oil-well drilling program crisscrossed the proposed ERP areas with a network of oil well pads and service roads, requiring a post-mining land use change. Eventually, whatever could go wrong, went right, and entry of lands into ERP was accomplished.« less

Perceived Use and Acceptance of Cloud Enterprise Resource Planning (ERP) Implementation in the Manufacturing Industries

ERIC Educational Resources Information Center

Adeboje, Adewale

2015-01-01

The purpose of this study was to gain an insight into perceived use and acceptance for implementing an enterprise resource planning system and the decision whether to contract out the enterprise resource planning (ERP) service to a cloud provider. Cloud-based ERP systems can provide many advantages to the normal implementation of the same systems…

An ERP Study of Emotional Face Processing in the Adult and Infant Brain

ERIC Educational Resources Information Center

Leppanen, Jukka M.; Moulson, Margaret C.; Vogel-Farley, Vanessa K.; Nelson, Charles A.

2007-01-01

To examine the ontogeny of emotional face processing, event-related potentials (ERPs) were recorded from adults and 7-month-old infants while viewing pictures of fearful, happy, and neutral faces. Face-sensitive ERPs at occipital-temporal scalp regions differentiated between fearful and neutral/happy faces in both adults (N170 was larger for fear)…

Individual Differences in ERPs during Mental Rotation of Characters: Lateralization, and Performance Level

ERIC Educational Resources Information Center

Beste, Christian; Heil, Martin; Konrad, Carsten

2010-01-01

The cognitive process of imaging an object turning around is called mental rotation. Many studies have been put forward analyzing mental rotation by means of event-related potentials (ERPs). Event-related potentials (ERPs) were measured during mental rotation of characters in a sample (N = 82) with a sufficient size to obtain even small effects. A…

Efficacy of cognitive-behavioral therapy for obsessive-compulsive disorder.

PubMed

McKay, Dean; Sookman, Debbie; Neziroglu, Fugen; Wilhelm, Sabine; Stein, Dan J; Kyrios, Michael; Matthews, Keith; Veale, David

2015-05-30

Cognitive-behavioral therapy (CBT), which encompasses exposure with response prevention (ERP) and cognitive therapy (CT), has demonstrated efficacy in the treatment of obsessive-compulsive disorder (OCD). However, the samples studied (reflecting the heterogeneity of OCD), the interventions examined (reflecting the heterogeneity of CBT), and the definitions of treatment response vary considerably across studies. This review examined the meta-analyses conducted on ERP and cognitive therapy (CT) for OCD. Also examined was the available research on long-term outcome associated with ERP and CT. The available research indicates that ERP is the first line evidence based psychotherapeutic treatment for OCD and that concurrent administration of cognitive therapy that targets specific symptom-related difficulties characteristic of OCD may improve tolerance of distress, symptom-related dysfunctional beliefs, adherence to treatment, and reduce drop out. Recommendations are provided for treatment delivery for OCD in general practice and other service delivery settings. The literature suggests that ERP and CT may be delivered in a wide range of clinical settings. Although the data are not extensive, the available research suggests that treatment gains following ERP are durable. Suggestions for future research to refine therapeutic outcome are also considered. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Efficacy of cognitive-behavioral therapy for obsessive-compulsive disorder.

PubMed

McKay, Dean; Sookman, Debbie; Neziroglu, Fugen; Wilhelm, Sabine; Stein, Dan J; Kyrios, Michael; Matthews, Keith; Veale, David

2015-02-28

Cognitive-behavioral therapy (CBT), which encompasses exposure with response prevention (ERP) and cognitive therapy, has demonstrated efficacy in the treatment of obsessive-compulsive disorder (OCD). However, the samples studied (reflecting the heterogeneity of OCD), the interventions examined (reflecting the heterogeneity of CBT), and the definitions of treatment response vary considerably across studies. This review examined the meta-analyses conducted on ERP and cognitive therapy (CT) for OCD. Also examined was the available research on long-term outcome associated with ERP and CT. The available research indicates that ERP is the first line evidence based psychotherapeutic treatment for OCD and that concurrent administration of cognitive therapy that targets specific symptom-related difficulties characteristic of OCD may improve tolerance of distress, symptom-related dysfunctional beliefs, adherence to treatment, and reduce drop out. Recommendations are provided for treatment delivery for OCD in general practice and other service delivery settings. The literature suggests that ERP and CT may be delivered in a wide range of clinical settings. Although the data are not extensive, the available research suggests that treatment gains following ERP are durable. Suggestions for future research to refine therapeutic outcome are also considered. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The difference in spatiotemporal dynamics between modus ponens and modus tollens in the Wason selection task: an event-related potential study.

PubMed

Li, Bingbing; Zhang, Meng; Luo, Junlong; Qiu, Jiang; Liu, Yijun

2014-06-13

High-density, event-related brain potentials (ERPs) were recorded to explore differences in spatiotemporal dynamics between modus ponens (MP) and modus tollens (MT) in the Wason selection task. Results showed that MP elicits a more positive P3b-like component than MT from 400 to 800 ms. MP appeared to occur earlier than MT in various stages of proposition testing, such as stimulus processing and response selection. ERP results showed that MT has a longer duration and more negative later negative component (LNC) than MP at 2,000 ms. This result suggests that MT occupies more cognitive resources than MP in the final stages of proposition testing. The short and small left frontal LNC obtained by MP implies examination of the expectable conclusion, whereas the long and large left frontal LNC elicited by MT may be involved in the retention operation of the card in working memory from the monitoring and inspecting putative conclusion in the later stages of proposition testing. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Evaluation of post-traumatic anosmia with MRI and chemosensory ERPs.

PubMed

Miao, Xutao; Yang, Ling; Gu, Hua; Ren, Yuanyuan; Chen, Guowei; Liu, Jia; Wei, Yongxiang

2015-08-01

Magnetic resonance imaging (MRI) and chemosensory event-related potentials (ERPs) are important methods to evaluate olfactory function, but there is lack of study to explore the application of MRI and chemosensory ERPs in the patients with traumatic anosmia. The data of 26 post-traumatic anosmic patients and 21 healthy controls were retrospectively surveyed; olfaction and olfactory pathway of all participants were measured clinically using the T&T olfactometer, the Sniffin' Sticks, chemosensory ERPs and MRI. All patients were anosmic based on complaints and clinical examinations. In five patients, the olfactory bulb volume was significantly lower than control group. In 18 patients, the olfactory sulcus (OS) depth was similar to control group, but all the participants had a deeper right OS (right = 7.79 ± 1.31, left = 7.06 ± 1.44, p < 0.01). Olfactory ERPs (oERPs) could be evoked in 17 patients, but these signals showed longer latencies and lower amplitude than controls in the N1 (latency p < 0.05, amplitude p < 0.01) and P2 (latency p < 0.01, amplitude p < 0.05) waves. Nine traumatic anosmic patients had no identifiable oERPs; most of them had olfactory center injury. Trigeminal ERPs were detected in all anosmic patients and controls; patients had longer latencies for N1 (p < 0.05) and P2 (p < 0.05) waves, while there was no similar change in amplitude. Older subjects had smaller OB volume and OS depth. Closed head injury could induce anosmia; the severity extent, injury site and subsequent consciousness are related to the olfaction. oERP is the gold standard for olfactory subjective examination; MRI could indicate the lesions on the olfactory pathway and reflect the possibility of detectable oERPs.

Intrinsic Factors for Continued ERP Learning: A Precursor to Interdisciplinary ERP Curriculum Design

ERIC Educational Resources Information Center

Chen, Kuanchin; Razi, Muhammad; Rienzo, Thomas

2011-01-01

Unilateral enterprise resource planning (ERP) curriculum improvements from the instructor's perspective are likely to generate only limited success. Understanding student motivations and beliefs with ERP systems is the missing link to effective ERP education. Relatively little attention in the ERP literature has been given to student learning…

Event-related potential studies of post-traumatic stress disorder: a critical review and synthesis

PubMed Central

2011-01-01

Despite the sparseness of the currently available data, there is accumulating evidence of information processing impairment in post-traumatic stress disorder (PTSD). Studies of event-related potentials (ERPs) are the main tool in real time examination of information processing. In this paper, we sought to critically review the ERP evidence of information processing abnormalities in patients with PTSD. We also examined the evidence supporting the existence of a relationship between ERP abnormalities and symptom profiles or severity in PTSD patients. An extensive Medline search was performed. Keywords included PTSD or post-traumatic stress disorder, electrophysiology or EEG, electrophysiology, P50, P100, N100, P2, P200, P3, P300, sensory gating, CNV (contingent negative variation) and MMN (mismatch negativity). We limited the review to ERP adult human studies with control groups which were reported in the English language. After applying our inclusion-exclusion review criteria, 36 studies were included. Subjects exposed to wide ranges of military and civilian traumas were studied in these reports. Presented stimuli were both auditory and visual. The most widely studied components included P300, P50 gating, N100 and P200. Most of the studies reported increased P300 response to trauma-related stimuli in PTSD patients. A smaller group of studies reported dampening of responses or no change in responses to trauma-related and/or unrelated stimuli. P50 studies were strongly suggestive of impaired gating in patients with PTSD. In conclusion, the majority of reports support evidence of information processing abnormalities in patients with PTSD diagnosis. The predominance of evidence suggests presence of mid-latency and late ERP components differences in PTSD patients in comparison to healthy controls. Heterogeneity of assessment methods used contributes to difficulties in reaching firm conclusions regarding the nature of these differences. We suggest that future ERP-PTSD studies utilize standardized assessment scales that provide detailed information regarding the symptom clusters and the degree of symptom severity. This would allow assessment of electrophysiological indices-clinical symptoms relationships. Based on the available data, we suggest that ERP abnormalities in PTSD are possibly affected by the level of illness severity. If supported by future research, ERP studies may be used for both initial assessment and treatment follow-up. PMID:22738160

Teasing apart the anticipatory and consummatory processing of monetary incentives: An event-related potential study of reward dynamics.

PubMed

Novak, Keisha D; Foti, Dan

2015-11-01

The monetary incentive delay (MID) task has been widely used in fMRI studies to investigate the neural networks involved in anticipatory and consummatory reward processing. Previous efforts to adapt the MID task for use with ERPs, however, have had limited success. Here, we sought to further decompose reward dynamics using a comprehensive set of anticipatory (cue-N2, cue-P3, contingent negative variation [CNV]) and consummatory ERPs (feedback negativity [FN], feedback P3 [fb-P3]). ERP data was recorded during adapted versions of the MID task across two experiments. Unlike previous studies, monetary incentive cues modulated the cue-N2, cue-P3, and CNV; however, cue-related ERPs and the CNV were uncorrelated with one another, indicating distinct anticipatory subprocesses. With regard to consummatory processing, FN amplitude primarily tracked outcome valence (reward vs. nonreward), whereas fb-P3 amplitude primarily tracked outcome salience (uncertain vs. certain). Independent modulation of the cue-P3 and fb-P3 was observed, indicating that these two P3 responses may uniquely capture the allocation of attention during anticipatory and consummatory reward processing, respectively. Overall, across two samples, consistent evidence of both anticipatory and consummatory ERP activity was observed on an adapted version of the MID paradigm, demonstrating for the first time how these ERP components may be integrated with one another to more fully characterize the time course of reward processing. This ERP-MID paradigm is well suited to parsing reward dynamics, and can be applied to both healthy and clinical populations. © 2015 Society for Psychophysiological Research.

Event-Related Potential Responses to Task Switching Are Sensitive to Choice of Spatial Filter

PubMed Central

Wong, Aaron S. W.; Cooper, Patrick S.; Conley, Alexander C.; McKewen, Montana; Fulham, W. Ross; Michie, Patricia T.; Karayanidis, Frini

2018-01-01

Event-related potential (ERP) studies using the task-switching paradigm show that multiple ERP components are modulated by activation of proactive control processes involved in preparing to repeat or switch task and reactive control processes involved in implementation of the current or new task. Our understanding of the functional significance of these ERP components has been hampered by variability in their robustness, as well as their temporal and scalp distribution across studies. The aim of this study is to examine the effect of choice of reference electrode or spatial filter on the number, timing and scalp distribution of ERP elicited during task-switching. We compared four configurations, including the two most common (i.e., average mastoid reference and common average reference) and two novel ones that aim to reduce volume conduction (i.e., reference electrode standardization technique (REST) and surface Laplacian) on mixing cost and switch cost effects in cue-locked and target-locked ERP waveforms in 201 healthy participants. All four spatial filters showed the same well-characterized ERP components that are typically seen in task-switching paradigms: the cue-locked switch positivity and target-locked N2/P3 effect. However, both the number of ERP effects associated with mixing and switch cost, and their temporal and spatial resolution were greater with the surface Laplacian transformation which revealed rapid temporal adjustments that were not identifiable with other spatial filters. We conclude that the surface Laplacian transformation may be more suited to characterize EEG signatures of complex spatiotemporal networks involved in cognitive control. PMID:29568260

The Effects of Face Inversion and Face Race on the P100 ERP.

PubMed

Colombatto, Clara; McCarthy, Gregory

2017-04-01

Research about the neural basis of face recognition has investigated the timing and anatomical substrates of different stages of face processing. Scalp-recorded ERP studies of face processing have focused on the N170, an ERP with a peak latency of ∼170 msec that has long been associated with the initial structural encoding of faces. However, several studies have reported earlier ERP differences related to faces, suggesting that face-specific processes might occur before N170. Here, we examined the influence of face inversion and face race on the timing of face-sensitive scalp-recorded ERPs by examining neural responses to upright and inverted line-drawn and luminance-matched white and black faces in a sample of white participants. We found that the P100 ERP evoked by inverted faces was significantly larger than that evoked by upright faces. Although this inversion effect was statistically significant at 100 msec, the inverted-upright ERP difference peaked at 138 msec, suggesting that it might represent an activity in neural sources that overlap with P100. Inverse modeling of the inversion effect difference waveform suggested possible neural sources in pericalcarine extrastriate visual cortex and lateral occipito-temporal cortex. We also found that the inversion effect difference wave was larger for white faces. These results are consistent with behavioral evidence that individuals process the faces of their own races more configurally than faces of other races. Taken together, the inversion and race effects observed in the current study suggest that configuration influences face processing by at least 100 msec.

Impacts of Earth rotation parameters on GNSS ultra-rapid orbit prediction: Derivation and real-time correction

NASA Astrophysics Data System (ADS)

Wang, Qianxin; Hu, Chao; Xu, Tianhe; Chang, Guobin; Hernández Moraleda, Alberto

2017-12-01

Analysis centers (ACs) for global navigation satellite systems (GNSSs) cannot accurately obtain real-time Earth rotation parameters (ERPs). Thus, the prediction of ultra-rapid orbits in the international terrestrial reference system (ITRS) has to utilize the predicted ERPs issued by the International Earth Rotation and Reference Systems Service (IERS) or the International GNSS Service (IGS). In this study, the accuracy of ERPs predicted by IERS and IGS is analyzed. The error of the ERPs predicted for one day can reach 0.15 mas and 0.053 ms in polar motion and UT1-UTC direction, respectively. Then, the impact of ERP errors on ultra-rapid orbit prediction by GNSS is studied. The methods for orbit integration and frame transformation in orbit prediction with introduced ERP errors dominate the accuracy of the predicted orbit. Experimental results show that the transformation from the geocentric celestial references system (GCRS) to ITRS exerts the strongest effect on the accuracy of the predicted ultra-rapid orbit. To obtain the most accurate predicted ultra-rapid orbit, a corresponding real-time orbit correction method is developed. First, orbits without ERP-related errors are predicted on the basis of ITRS observed part of ultra-rapid orbit for use as reference. Then, the corresponding predicted orbit is transformed from GCRS to ITRS to adjust for the predicted ERPs. Finally, the corrected ERPs with error slopes are re-introduced to correct the predicted orbit in ITRS. To validate the proposed method, three experimental schemes are designed: function extrapolation, simulation experiments, and experiments with predicted ultra-rapid orbits and international GNSS Monitoring and Assessment System (iGMAS) products. Experimental results show that using the proposed correction method with IERS products considerably improved the accuracy of ultra-rapid orbit prediction (except the geosynchronous BeiDou orbits). The accuracy of orbit prediction is enhanced by at least 50% (error related to ERP) when a highly accurate observed orbit is used with the correction method. For iGMAS-predicted orbits, the accuracy improvement ranges from 8.5% for the inclined BeiDou orbits to 17.99% for the GPS orbits. This demonstrates that the correction method proposed by this study can optimize the ultra-rapid orbit prediction.

The auditory P50 component to onset and offset of sound

PubMed Central

Pratt, Hillel; Starr, Arnold; Michalewski, Henry J.; Bleich, Naomi; Mittelman, Nomi

2008-01-01

Objective: The auditory Event-Related Potentials (ERP) component P50 to sound onset and offset have been reported to be similar, but their magnetic homologue has been reported absent to sound offset. We compared the spatio-temporal distribution of cortical activity during P50 to sound onset and offset, without confounds of spectral change. Methods: ERPs were recorded in response to onsets and offsets of silent intervals of 0.5 s (gaps) appearing randomly in otherwise continuous white noise and compared to ERPs to randomly distributed click pairs with half second separation presented in silence. Subjects were awake and distracted from the stimuli by reading a complicated text. Measures of P50 included peak latency and amplitude, as well as source current density estimates to the clicks and sound onsets and offsets. Results P50 occurred in response to noise onsets and to clicks, while to noise offset it was absent. Latency of P50 was similar to noise onset (56 msec) and to clicks (53 msec). Sources of P50 to noise onsets and clicks included bilateral superior parietal areas. In contrast, noise offsets activated left inferior temporal and occipital areas at the time of P50. Source current density was significantly higher to noise onset than offset in the vicinity of the temporo-parietal junction. Conclusions: P50 to sound offset is absent compared to the distinct P50 to sound onset and to clicks, at different intracranial sources. P50 to stimulus onset and to clicks appears to reflect preattentive arousal by a new sound in the scene. Sound offset does not involve a new sound and hence the absent P50. Significance: Stimulus onset activates distinct early cortical processes that are absent to offset. PMID:18055255

Research in China on event-related potentials in patients with schizophrenia

PubMed Central

Wang, Jijun; Guo, Qian

2012-01-01

Abstract Event-related potentials (ERPs) are objective electrophysiological indicators that can be used to assess cognitive processes in the human brain. Psychiatric researchers in China have applied this method to study schizophrenia since the early 1980s. ERP measures used in the study of schizophrenia include contingent negative variation (CNV), P300, mismatch negativity (MMN), error-related negativity (ERN) and auditory P50 inhibition. This review summarizes the main findings of ERP research in patients with schizophrenia reported by Chinese investigators. PMID:25324605

An empirical analysis of ERP adoption by oil and gas firms

NASA Astrophysics Data System (ADS)

Romero, Jorge

2005-07-01

Despite the growing popularity of enterprise-resource-planning (ERP) systems for the information technology infrastructure of large and medium-sized businesses, there is limited empirical evidence on the competitive benefits of ERP implementations. Case studies of individual firms provide insights but do not provide sufficient evidence to draw reliable inferences and cross-sectional studies of firms in multiple industries provide a broad-brush perspective of the performance effects associated with ERP installations. To narrow the focus to a specific competitive arena, I analyze the impact of ERP adoption on various dimensions of performance for firms in the Oil and Gas Industry. I selected the Oil and Gas Industry because several companies installed a specific type of ERP system, SAP R/3, during the period from 1990 to 2002. In fact, SAP was the dominant provider of enterprise software to oil and gas companies during this period. I evaluate performance of firms that implemented SAP R/3 relative to firms that did not adopt ERP systems in the pre-implementation, implementation and post-implementation periods. My analysis takes two different approaches, the first from a financial perspective and the second from a strategic perspective. Using the Sloan (General Motors) model commonly applied in financial statement analysis, I examine changes in performance for ERP-adopting firms versus non-adopting firms along the dimensions of asset utilization and return on sales. Asset utilization is more closely aligned with changes in leanness of operations, and return on sales is more closely aligned with customer-value-added. I test hypotheses related to the timing and magnitude of the impact of ERP implementation with respect to leanness of operations and customer value added. I find that SAP-adopting companies performed relatively better in terms of asset turnover than non-SAP-adopting companies during both the implementation and post-implementation periods and that SAP-adopting firms outperformed non-SAP-adopting firms in terms of return on sales during the post-implementation period. These findings indicate that the impact of ERP implementation on return on sales occurred after an assimilation period. I perform an analysis of the impact of ERP in the Oil and Gas Industry using strategic performance metrics described in Banker et al. (1996) including profitability, productivity, price recovery, product mix, and capacity utilization. My results show that the benefits obtained from ERP implementation in terms of productivity and capacity utilization are persistently positive during and after the installation.

Disturbances in Response Inhibition and Emotional Processing as Potential Pathways to Violence in Schizophrenia: A High-Density Event-Related Potential Study

PubMed Central

Krakowski, Menahem I.; De Sanctis, Pierfilippo; Foxe, John J.; Hoptman, Matthew J.; Nolan, Karen; Kamiel, Stephanie; Czobor, Pal

2016-01-01

Objective: Increased susceptibility to emotional triggers and poor response inhibition are important in the etiology of violence in schizophrenia. Our goal was to evaluate abnormalities in neurophysiological mechanisms underlying response inhibition and emotional processing in violent patients with schizophrenia (VS) and 3 different comparison groups: nonviolent patients (NV), healthy controls (HC) and nonpsychotic violent subjects (NPV). Methods: We recorded high-density Event-Related Potentials (ERPs) and behavioral responses during an Emotional Go/NoGo Task in 35 VS, 24 NV, 28 HC and 31 NPV subjects. We also evaluated psychiatric symptoms and impulsivity. Results: The neural and behavioral deficits in violent patients were most pronounced when they were presented with negative emotional stimuli: They responded more quickly than NV when they made commission errors (ie, failure of inhibition), and evidenced N2 increases and P3 decreases. In contrast, NVs showed little change in reaction time or ERP amplitude with emotional stimuli. These N2 and P3 amplitude changes in VSs showed a strong association with greater impulsivity. Besides these group specific changes, VSs shared deficits with NV, mostly N2 reduction, and with violent nonpsychotic subjects, particularly P3 reduction. Conclusion: Negative affective triggers have a strong impact on violent patients with schizophrenia which may have both behavioral and neural manifestations. The resulting activation could interfere with response inhibition. The affective disruption of response inhibition, identified in this study, may index an important pathway to violence in schizophrenia and suggest new modes of treatment. PMID:26895845

Re-examination of Chinese semantic processing and syntactic processing: evidence from conventional ERPs and reconstructed ERPs by residue iteration decomposition (RIDE).

PubMed

Wang, Fang; Ouyang, Guang; Zhou, Changsong; Wang, Suiping

2015-01-01

A number of studies have explored the time course of Chinese semantic and syntactic processing. However, whether syntactic processing occurs earlier than semantics during Chinese sentence reading is still under debate. To further explore this issue, an event-related potentials (ERPs) experiment was conducted on 21 native Chinese speakers who read individually-presented Chinese simple sentences (NP1+VP+NP2) word-by-word for comprehension and made semantic plausibility judgments. The transitivity of the verbs was manipulated to form three types of stimuli: congruent sentences (CON), sentences with a semantically violated NP2 following a transitive verb (semantic violation, SEM), and sentences with a semantically violated NP2 following an intransitive verb (combined semantic and syntactic violation, SEM+SYN). The ERPs evoked from the target NP2 were analyzed by using the Residue Iteration Decomposition (RIDE) method to reconstruct the ERP waveform blurred by trial-to-trial variability, as well as by using the conventional ERP method based on stimulus-locked averaging. The conventional ERP analysis showed that, compared with the critical words in CON, those in SEM and SEM+SYN elicited an N400-P600 biphasic pattern. The N400 effects in both violation conditions were of similar size and distribution, but the P600 in SEM+SYN was bigger than that in SEM. Compared with the conventional ERP analysis, RIDE analysis revealed a larger N400 effect and an earlier P600 effect (in the time window of 500-800 ms instead of 570-810ms). Overall, the combination of conventional ERP analysis and the RIDE method for compensating for trial-to-trial variability confirmed the non-significant difference between SEM and SEM+SYN in the earlier N400 time window. Converging with previous findings on other Chinese structures, the current study provides further precise evidence that syntactic processing in Chinese does not occur earlier than semantic processing.

The roles of protein disulphide isomerase family A, member 3 (ERp57) and surface thiol/disulphide exchange in human spermatozoa-zona pellucida binding.

PubMed

Wong, Chi-Wai; Lam, Kevin K W; Lee, Cheuk-Lun; Yeung, William S B; Zhao, Wei E; Ho, Pak-Chung; Ou, Jian-Ping; Chiu, Philip C N

2017-04-01

Are multimeric sperm plasma membrane protein complexes, ERp57 and sperm surface thiol content involved in human spermatozoa-zona pellucida (ZP) interaction? ERp57 is a component of a multimeric spermatozoa-ZP receptor complex involved in regulation of human spermatozoa-ZP binding via up-regulation of sperm surface thiol content. A spermatozoon acquires its fertilization capacity within the female reproductive tract by capacitation. Spermatozoa-ZP receptor is suggested to be a composite structure that is assembled into a functional complex during capacitation. Sperm surface thiol content is elevated during capacitation. ERp57 is a protein disulphide isomerase that modulates the thiol-disulphide status of proteins. The binding ability and components of protein complexes in extracted membrane protein fractions of spermatozoa were studied. The roles of capacitation, thiol-disulphide reagent treatments and ERp57 on sperm functions and sperm surface thiol content were assessed. Spermatozoa were obtained from semen samples from normozoospermic men. Human oocytes were obtained from an assisted reproduction programme. Blue native polyacrylamide gel electrophoresis, western ligand blotting and mass spectrometry were used to identify the components of solubilized ZP/ZP3-binding complexes. The localization and expression of sperm surface thiol and ERp57 were studied by immunostaining and sperm surface protein biotinylation followed by western blotting. Sperm functions were assessed by standard assays. Several ZP-binding complexes were isolated from the cell membrane of capacitated spermatozoa. ERp57 was a component of one of these complexes. Capacitation significantly increased the sperm surface thiol content, acrosomal thiol distribution and ERp57 expression on sperm surface. Sperm surface thiol and ERp57 immunoreactivity were localized to the acrosomal region of spermatozoa, a region responsible for ZP-binding. Up-regulation of the surface thiol content or ERp57 surface expression in vitro stimulated ZP-binding capacity of human spermatozoa. Blocking of ERp57 function by specific antibody or inhibitors against ERp57 reduced the surface thiol content and ZP-binding capacity of human spermatozoa. N/A. The mechanisms by which up-regulation of surface thiol content stimulates spermatozoa-ZP binding have not been depicted. Thiol-disulphide exchange is a crucial event in capacitation. ERp57 modulates the event and the subsequent fertilization process. Modulation of the surface thiol content of the spermatozoa of subfertile men may help to increase fertilization rate in assisted reproduction. This work was supported by The Hong Kong Research Grant Council Grant HKU764611 and HKU764512M to P.C.N.C. The authors have no competing interests. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Electrophysiological assessments of cognition and sensory processing in TBI: applications for diagnosis, prognosis and rehabilitation.

PubMed

Folmer, Robert L; Billings, Curtis J; Diedesch-Rouse, Anna C; Gallun, Frederick J; Lew, Henry L

2011-10-01

Traumatic brain injuries are often associated with damage to sensory and cognitive processing pathways. Because evoked potentials (EPs) and event-related potentials (ERPs) are generated by neuronal activity, they are useful for assessing the integrity of neural processing capabilities in patients with traumatic brain injury (TBI). This review of somatosensory, auditory and visual ERPs in assessments of TBI patients is provided with the hope that it will be of interest to clinicians and researchers who conduct or interpret electrophysiological evaluations of this population. Because this article reviews ERP studies conducted in three different sensory modalities, involving patients with a wide range of TBI severity ratings and circumstances, it is difficult to provide a coherent summary of findings. However, some general trends emerge that give rise to the following observations and recommendations: 1) bilateral absence of somatosensory evoked potentials (SEPs) is often associated with poor clinical prognosis and outcome; 2) the presence of normal ERPs does not guarantee favorable outcome; 3) ERPs evoked by a variety of sensory stimuli should be used to evaluate TBI patients, especially those with severe injuries; 4) time since onset of injury should be taken into account when conducting ERP evaluations of TBI patients or interpreting results; 5) because sensory deficits (e.g., vision impairment or hearing loss) affect ERP results, tests of peripheral sensory integrity should be conducted in conjunction with ERP recordings; and 6) patients' state of consciousness, physical and cognitive abilities to respond and follow directions should be considered when conducting or interpreting ERP evaluations. Published by Elsevier B.V.

Purification and biochemical characterization of native ERp29 from rat liver

PubMed Central

2004-01-01

ERp29 is a recently characterized resident of the ER (endoplasmic reticulum) lumen that has broad biological significance, being expressed ubiquitously and abundantly in animal cells. As an apparent housekeeper, ERp29 is thought to be a general folding assistant for secretory proteins and to probably function as a PDI (protein disulphide isomerase)-like molecular chaperone. In the present paper, we report the first purification to homogeneity and direct functional analysis of native ERp29, which has led to the unexpected finding that ERp29 lacks PDI-like folding activities. ERp29 was purified 4800-fold in non-denaturing conditions exploiting an unusual affinity for heparin. Two additional biochemical hallmarks that will assist the classification of ERp29 homologues were identified, namely the idiosyncratic behaviours of ERp29 on size-exclusion chromatography (Mrmonomeric mass). In contrast with PDI and parallel-purified co-residents (calreticulin, ERp60), native ERp29 lacked classical chaperone, disulphide reductase and isomerase, and calcium-binding activities. In the chaperone assays, ERp29 neither protected substrate proteins against thermal aggregation nor interacted stably with chemically denatured proteins as detected by cross-linking. ERp29 also did not exhibit helper activity toward calreticulin (chaperone) or PDI and ERp60 (disulphide reductase). By refuting long-standing predictions about chaperone activity, these results expose ERp29 as a functionally distinct member of the ER machinery and prompt a revised hypothesis that ERp29 acts as a non-classical folding assistant. The native preparation and biochemical hallmarks established here provide a useful foundation for ongoing efforts to resolve the functional orphan status of ERp29. PMID:15500441

Atrial Arrhythmia in Ageing Spontaneously Hypertensive Rats: Unraveling the Substrate in Hypertension and Ageing

PubMed Central

Lau, Dennis H.; Shipp, Nicholas J.; Kelly, Darren J.; Thanigaimani, Shivshankar; Neo, Melissa; Kuklik, Pawel; Lim, Han S.; Zhang, Yuan; Drury, Karen; Wong, Christopher X.; Chia, Nicholas H.; Brooks, Anthony G.; Dimitri, Hany; Saint, David A.; Brown, Lindsay; Sanders, Prashanthan

2013-01-01

Background Both ageing and hypertension are known risk factors for atrial fibrillation (AF) although the pathophysiological contribution or interaction of the individual factors remains poorly understood. Here we aim to delineate the arrhythmogenic atrial substrate in mature spontaneously hypertensive rats (SHR). Methods SHR were studied at 12 and 15 months of age (n = 8 per group) together with equal numbers of age-matched normotensive Wistar-Kyoto control rats (WKY). Electrophysiologic study was performed on superfused isolated right and left atrial preparations using a custom built high-density multiple-electrode array to determine effective refractory periods (ERP), atrial conduction and atrial arrhythmia inducibility. Tissue specimens were harvested for structural analysis. Results Compared to WKY controls, the SHR demonstrated: Higher systolic blood pressure (p<0.0001), bi-atrial enlargement (p<0.05), bi-ventricular hypertrophy (p<0.05), lower atrial ERP (p = 0.008), increased atrial conduction heterogeneity (p = 0.001) and increased atrial interstitial fibrosis (p = 0.006) & CD68-positive macrophages infiltration (p<0.0001). These changes resulted in higher atrial arrhythmia inducibility (p = 0.01) and longer induced AF episodes (p = 0.02) in 15-month old SHR. Ageing contributed to incremental bi-atrial hypertrophy (p<0.01) and atrial conduction heterogeneity (p<0.01) without affecting atrial ERP, fibrosis and arrhythmia inducibility. The limited effect of ageing on the atrial substrate may be secondary to the reduction in CD68-positive macrophages. Conclusions Significant atrial electrical and structural remodeling is evident in the ageing spontaneously hypertensive rat atria. Concomitant hypertension appears to play a greater pathophysiological role than ageing despite their compounding effect on the atrial substrate. Inflammation is pathophysiologically linked to the pro-fibrotic changes in the hypertensive atria. PMID:24013508

Adapted wavelet transform improves time-frequency representations: a study of auditory elicited P300-like event-related potentials in rats

NASA Astrophysics Data System (ADS)

Richard, Nelly; Laursen, Bettina; Grupe, Morten; Drewes, Asbjørn M.; Graversen, Carina; Sørensen, Helge B. D.; Bastlund, Jesper F.

2017-04-01

Objective. Active auditory oddball paradigms are simple tone discrimination tasks used to study the P300 deflection of event-related potentials (ERPs). These ERPs may be quantified by time-frequency analysis. As auditory stimuli cause early high frequency and late low frequency ERP oscillations, the continuous wavelet transform (CWT) is often chosen for decomposition due to its multi-resolution properties. However, as the conventional CWT traditionally applies only one mother wavelet to represent the entire spectrum, the time-frequency resolution is not optimal across all scales. To account for this, we developed and validated a novel method specifically refined to analyse P300-like ERPs in rats. Approach. An adapted CWT (aCWT) was implemented to preserve high time-frequency resolution across all scales by commissioning of multiple wavelets operating at different scales. First, decomposition of simulated ERPs was illustrated using the classical CWT and the aCWT. Next, the two methods were applied to EEG recordings obtained from prefrontal cortex in rats performing a two-tone auditory discrimination task. Main results. While only early ERP frequency changes between responses to target and non-target tones were detected by the CWT, both early and late changes were successfully described with strong accuracy by the aCWT in rat ERPs. Increased frontal gamma power and phase synchrony was observed particularly within theta and gamma frequency bands during deviant tones. Significance. The study suggests superior performance of the aCWT over the CWT in terms of detailed quantification of time-frequency properties of ERPs. Our methodological investigation indicates that accurate and complete assessment of time-frequency components of short-time neural signals is feasible with the novel analysis approach which may be advantageous for characterisation of several types of evoked potentials in particularly rodents.

Teaching ERP Systems: A Multi-Perspective View on the ERP System Market

ERIC Educational Resources Information Center

Winkelmann, Axel; Leyh, Christian

2010-01-01

In order to increase the diversity in IS education, we discuss an approach for teaching medium-sized ERP systems in university courses. Many of today's IS curricula are biased toward a few large ERP packages. Nevertheless, these ERP systems are only a part of the ERP market. Therefore, this paper describes a course outline for an additional course…

Exploring Education Culture by Employing Hofstede?s Cultural Dimensions to Evaluate the Effectiveness of the Current ERP Training Approach in Thailand

ERIC Educational Resources Information Center

Chayakonvikom, Monta; Fuangvut, Parin; Cannell, Stephen

2016-01-01

ERP training is a critical success factor in ERP implementation. The current ERP training was largely ineffective and caused user resistance and ERP implementation failure. The objective of this paper is to investigate whether the current ERP training approach can accommodate the cultural learning behaviors of end-users. Hofstede's cultural…

Neural correlates of emotional intelligence in a visual emotional oddball task: an ERP study.

PubMed

Raz, Sivan; Dan, Orrie; Zysberg, Leehu

2014-11-01

The present study was aimed at identifying potential behavioral and neural correlates of Emotional Intelligence (EI) by using scalp-recorded Event-Related Potentials (ERPs). EI levels were defined according to both self-report questionnaire and a performance-based ability test. We identified ERP correlates of emotional processing by using a visual-emotional oddball paradigm, in which subjects were confronted with one frequent standard stimulus (a neutral face) and two deviant stimuli (a happy and an angry face). The effects of these faces were then compared across groups with low and high EI levels. The ERP results indicate that participants with high EI exhibited significantly greater mean amplitudes of the P1, P2, N2, and P3 ERP components in response to emotional and neutral faces, at frontal, posterior-parietal and occipital scalp locations. P1, P2 and N2 are considered indexes of attention-related processes and have been associated with early attention to emotional stimuli. The later P3 component has been thought to reflect more elaborative, top-down, emotional information processing including emotional evaluation and memory encoding and formation. These results may suggest greater recruitment of resources to process all emotional and non-emotional faces at early and late processing stages among individuals with higher EI. The present study underscores the usefulness of ERP methodology as a sensitive measure for the study of emotional stimuli processing in the research field of EI. Copyright © 2014 Elsevier Inc. All rights reserved.

Influence of long-term Sahaja Yoga meditation practice on emotional processing in the brain: An ERP study.

PubMed

Reva, N V; Pavlov, S V; Loktev, K V; Korenyok, V V; Aftanas, L I

2014-12-05

Despite growing interest in meditation as a tool for alternative therapy of stress-related and psychosomatic diseases, brain mechanisms of beneficial influences of meditation practice on health and quality of life are still unclear. We propose that the key point is a persistent change in emotional functioning, specifically the modulation of the early appraisal of motivational significance of events. The main aim was to study the effects of long-term meditation practice on event-related brain potentials (ERPs) during affective picture viewing. ERPs were recorded in 20 long-term Sahaja Yoga meditators and 20 control subjects without prior experience in meditation. The meditators' mid-latency (140-400ms) ERPs were attenuated for both positive and negative pictures (i.e. there were no arousal-related increases in ERP positivity) and this effect was more prominent over the right hemisphere. However, we found no differences in the long latency (400-800ms) responses to emotional images, associated with meditation practice. In addition we found stronger ERP negativity in the time window 200-300ms for meditators compared to the controls, regardless of picture valence. We assume that long-term meditation practice enhances frontal top-down control over fast automatic salience detection, based on amygdala functions. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Electrophysiological Responses to Expectancy Violations in Semantic and Gambling Tasks: A Comparison of Different EEG Reference Approaches

PubMed Central

Li, Ya; Wang, Yongchun; Zhang, Baoqiang; Wang, Yonghui; Zhou, Xiaolin

2018-01-01

Dynamically evaluating the outcomes of our actions and thoughts is a fundamental cognitive ability. Given its excellent temporal resolution, the event-related potential (ERP) technology has been used to address this issue. The feedback-related negativity (FRN) component of ERPs has been studied intensively with the averaged linked mastoid reference method (LM). However, it is unknown whether FRN can be induced by an expectancy violation in an antonym relations context and whether LM is the most suitable reference approach. To address these issues, the current research directly compared the ERP components induced by expectancy violations in antonym expectation and gambling tasks with a within-subjects design and investigated the effect of the reference approach on the experimental effects. Specifically, we systematically compared the influence of the LM, reference electrode standardization technique (REST) and average reference (AVE) approaches on the amplitude, scalp distribution and magnitude of ERP effects as a function of expectancy violation type. The expectancy deviation in the antonym expectation task elicited an N400 effect that differed from the FRN effect induced in the gambling task; this difference was confirmed by all the three reference methods. Both the amplitudes of the ERP effects (N400 and FRN) and the magnitude as the expectancy violation increased were greater under the LM approach than those under the REST approach, followed by those under the AVE approach. Based on the statistical results, the electrode sites that showed the N400 and FRN effects critically depended on the reference method, and the results of the REST analysis were consistent with previous ERP studies. Combined with evidence from simulation studies, we suggest that REST is an optional reference method to be used in future ERP data analysis. PMID:29615858

The Effects of Acute Dopamine Precursor Depletion on the Cognitive Control Functions of Performance Monitoring and Conflict Processing: An Event-Related Potential (ERP) Study.

PubMed

Larson, Michael J; Clayson, Peter E; Primosch, Mark; Leyton, Marco; Steffensen, Scott C

2015-01-01

Studies using medications and psychiatric populations implicate dopamine in cognitive control and performance monitoring processes. However, side effects associated with medication or studying psychiatric groups may confound the relationship between dopamine and cognitive control. To circumvent such possibilities, we utilized a randomized, double-blind, placebo-controlled, within-subjects design wherein participants were administered a nutritionally-balanced amino acid mixture (BAL) and an amino acid mixture deficient in the dopamine precursors tyrosine (TYR) and phenylalanine (PHE) on two separate occasions. Order of sessions was randomly assigned. Cognitive control and performance monitoring were assessed using response times (RT), error rates, the N450, an event-related potential (ERP) index of conflict monitoring, the conflict slow potential (conflict SP), an ERP index of conflict resolution, and the error-related negativity (ERN) and error positivity (Pe), ERPs associated with performance monitoring. Participants were twelve males who completed a Stroop color-word task while ERPs were collected four hours following acute PHE and TYR depletion (APTD) or balanced (BAL) mixture ingestion in two separate sessions. N450 and conflict SP ERP amplitudes significantly differentiated congruent from incongruent trials, but did not differ as a function of APTD or BAL mixture ingestion. Similarly, ERN and Pe amplitudes showed significant differences between error and correct trials that were not different between APTD and BAL conditions. Findings indicate that acute dopamine precursor depletion does not significantly alter cognitive control and performance monitoring ERPs. Current results do not preclude the role of dopamine in these processes, but suggest that multiple methods for dopamine-related hypothesis testing are needed.

Hippocampal P3-like auditory event-related potentials are disrupted in a rat model of cholinergic degeneration in Alzheimer's disease: reversal by donepezil treatment.

PubMed

Laursen, Bettina; Mørk, Arne; Kristiansen, Uffe; Bastlund, Jesper Frank

2014-01-01

P300 (P3) event-related potentials (ERPs) have been suggested to be an endogenous marker of cognitive function and auditory oddball paradigms are frequently used to evaluate P3 ERPs in clinical settings. Deficits in P3 amplitude and latency reflect some of the neurological dysfunctions related to several psychiatric and neurological diseases, e.g., Alzheimer's disease (AD). However, only a very limited number of rodent studies have addressed the back-translational validity of the P3-like ERPs as suitable markers of cognition. Thus, the potential of rodent P3-like ERPs to predict pro-cognitive effects in humans remains to be fully validated. The current study characterizes P3-like ERPs in the 192-IgG-SAP (SAP) rat model of the cholinergic degeneration associated with AD. Following training in a combined auditory oddball and lever-press setup, rats were subjected to bilateral intracerebroventricular infusion of 1.25 μg SAP or PBS (sham lesion) and recording electrodes were implanted in hippocampal CA1. Relative to sham-lesioned rats, SAP-lesioned rats had significantly reduced amplitude of P3-like ERPs. P3 amplitude was significantly increased in SAP-treated rats following pre-treatment with 1 mg/kg donepezil. Infusion of SAP reduced the hippocampal choline acetyltransferase activity by 75%. Behaviorally defined cognitive performance was comparable between treatment groups. The present study suggests that AD-like deficits in P3-like ERPs may be mimicked by the basal forebrain cholinergic degeneration induced by SAP. SAP-lesioned rats may constitute a suitable model to test the efficacy of pro-cognitive substances in an applied experimental setup.

Rhythmic Activity and Individual Variability in Recognition Memory: Theta Oscillations Correlate with Performance whereas Alpha Oscillations Correlate with ERPs.

PubMed

Chen, Yvonne Y; Caplan, Jeremy B

2017-01-01

During study trials of a recognition memory task, alpha (∼10 Hz) oscillations decrease, and concurrently, theta (4-8 Hz) oscillations increase when later memory is successful versus unsuccessful (subsequent memory effect). Likewise, at test, reduced alpha and increased theta activity are associated with successful memory (retrieval success effect). Here we take an individual-differences approach to test three hypotheses about theta and alpha oscillations in verbal, old/new recognition, measuring the difference in oscillations between hit trials and miss trials. First, we test the hypothesis that theta and alpha oscillations have a moderately mutually exclusive relationship; but no support for this hypothesis was found. Second, we test the hypothesis that theta oscillations explain not only memory effects within participants, but also individual differences. Supporting this prediction, durations of theta (but not alpha) oscillations at study and at test correlated significantly with d' across participants. Third, we test the hypothesis that theta and alpha oscillations reflect familiarity and recollection processes by comparing oscillation measures to ERPs that are implicated in familiarity and recollection. The alpha-oscillation effects correlated with some ERP measures, but inversely, suggesting that the actions of alpha oscillations on memory processes are distinct from the roles of familiarity- and recollection-linked ERP signals. The theta-oscillation measures, despite differentiating hits from misses, did not correlate with any ERP measure; thus, theta oscillations may reflect elaborative processes not tapped by recollection-related ERPs. Our findings are consistent with alpha oscillations reflecting visual inattention, which can modulate memory, and with theta oscillations supporting recognition memory in ways that complement the most commonly studied ERPs.

Need for speed: evaluating slopes of OCD recovery in behavior therapy enhanced with d-cycloserine.

PubMed

Chasson, Gregory S; Buhlmann, Ulrike; Tolin, David F; Rao, Sowmya R; Reese, Hannah E; Rowley, Theresa; Welsh, Kaitlyn S; Wilhelm, Sabine

2010-07-01

Evidence suggests that the antibiotic d-cycloserine (DCS) enhances the treatment effects of exposure and response prevention (ERP) for Obsessive-Compulsive Disorder (OCD). Further, evidence suggests that the effects of DCS diminish partway through treatment, but it is unclear to what extent. In an effort to evaluate these issues, the current study re-analyzes data from a 10-session randomized controlled trial of ERP+DCS versus ERP+placebo in a sample of 22 adults with OCD. We analyzed repeated-measures mixed models with random slopes and intercepts across different intervals: sessions 1-10, 1-5, and 6-10. The results indicate that the course of ERP was 2.3 times faster over the full 10 sessions for the DCS compared to the placebo group, and nearly six times quicker in the first half of ERP. Further interpretation of the results suggests that DCS does not amplify the effects of ERP, but instead initiates treatment effects sooner in treatment. In addition, DCS does not necessarily lose its effect over repeated use, but instead may exhaust its maximum utility after effectively jump-starting ERP. Ultimately, DCS may provide a means for curtailing treatment costs, decreasing treatment dropout and refusal rates, and enhancing access to care. Copyright 2010 Elsevier Ltd. All rights reserved.

Mindfulness based cognitive therapy may improve emotional processing in bipolar disorder: pilot ERP and HRV study.

PubMed

Howells, Fleur M; Laurie Rauch, H G; Ives-Deliperi, Victoria L; Horn, Neil R; Stein, Dan J

2014-06-01

Emotional processing in bipolar disorder (BD) is impaired. We aimed to measure the effects of mindfulness based cognitive-behavioral therapy (MBCT) in BD on emotional processing, as measured by event related potentials (ERP) and by heart rate variability (HRV). ERP and HRV were recorded during the completion of a visual matching task, which included object matching, affect matching, and affect labeling. Individuals with BD (n = 12) were compared with controls (n = 9) to obtain baseline data prior to the individuals with BD undergoing an 8-week MBCT intervention. ERP and HRV recording was repeated after the MBCT intervention in BD. Participants with BD had exaggerated ERP N170 amplitude and increased HRV HF peak compared to controls, particularly during the affect matching condition. After an 8-week MBCT intervention, participants with BD showed attenuation of ERP N170 amplitude and reduced HRV HF peak. Our findings support findings from the literature emphasizing that emotional processing in BD is altered, and suggesting that MBCT may improve emotional processing in BD.

Gaze-independent ERP-BCIs: augmenting performance through location-congruent bimodal stimuli

PubMed Central

Thurlings, Marieke E.; Brouwer, Anne-Marie; Van Erp, Jan B. F.; Werkhoven, Peter

2014-01-01

Gaze-independent event-related potential (ERP) based brain-computer interfaces (BCIs) yield relatively low BCI performance and traditionally employ unimodal stimuli. Bimodal ERP-BCIs may increase BCI performance due to multisensory integration or summation in the brain. An additional advantage of bimodal BCIs may be that the user can choose which modality or modalities to attend to. We studied bimodal, visual-tactile, gaze-independent BCIs and investigated whether or not ERP components’ tAUCs and subsequent classification accuracies are increased for (1) bimodal vs. unimodal stimuli; (2) location-congruent vs. location-incongruent bimodal stimuli; and (3) attending to both modalities vs. to either one modality. We observed an enhanced bimodal (compared to unimodal) P300 tAUC, which appeared to be positively affected by location-congruency (p = 0.056) and resulted in higher classification accuracies. Attending either to one or to both modalities of the bimodal location-congruent stimuli resulted in differences between ERP components, but not in classification performance. We conclude that location-congruent bimodal stimuli improve ERP-BCIs, and offer the user the possibility to switch the attended modality without losing performance. PMID:25249947

Bilateral brain reorganization with memantine and constraint-induced aphasia therapy in chronic post-stroke aphasia: An ERP study.

PubMed

Barbancho, Miguel A; Berthier, Marcelo L; Navas-Sánchez, Patricia; Dávila, Guadalupe; Green-Heredia, Cristina; García-Alberca, José M; Ruiz-Cruces, Rafael; López-González, Manuel V; Dawid-Milner, Marc S; Pulvermüller, Friedemann; Lara, J Pablo

2015-01-01

Changes in ERP (P100 and N400) and root mean square (RMS) were obtained during a silent reading task in 28 patients with chronic post-stroke aphasia in a randomized, double-blind, placebo-controlled trial of both memantine and constraint-induced aphasia therapy (CIAT). Participants received memantine/placebo alone (weeks 0-16), followed by drug treatment combined with CIAT (weeks 16-18), and then memantine/placebo alone (weeks 18-20). ERP/RMS values (week 16) decreased more in the memantine group than in the placebo group. During CIAT application (weeks 16-18), improvements in aphasia severity and ERP/RMS values were amplified by memantine and changes remained stable thereafter (weeks 18-20). Changes in ERP/RMS occurred in left and right hemispheres and correlated with gains in language performance. No changes in ERP/RMS were found in a healthy group in two separated evaluations. Our results show that aphasia recovery induced by both memantine alone and in combination with CIAT is indexed by bilateral cortical potentials. Copyright © 2015 Elsevier Inc. All rights reserved.

Adaptation to Emotional Conflict: Evidence from a Novel Face Emotion Paradigm

PubMed Central

Clayson, Peter E.; Larson, Michael J.

2013-01-01

The preponderance of research on trial-by-trial recruitment of affective control (e.g., conflict adaptation) relies on stimuli wherein lexical word information conflicts with facial affective stimulus properties (e.g., the face-Stroop paradigm where an emotional word is overlaid on a facial expression). Several studies, however, indicate different neural time course and properties for processing of affective lexical stimuli versus affective facial stimuli. The current investigation used a novel task to examine control processes implemented following conflicting emotional stimuli with conflict-inducing affective face stimuli in the absence of affective words. Forty-one individuals completed a task wherein the affective-valence of the eyes and mouth were either congruent (happy eyes, happy mouth) or incongruent (happy eyes, angry mouth) while high-density event-related potentials (ERPs) were recorded. There was a significant congruency effect and significant conflict adaptation effects for error rates. Although response times (RTs) showed a significant congruency effect, the effect of previous-trial congruency on current-trial RTs was only present for current congruent trials. Temporospatial principal components analysis showed a P3-like ERP source localized using FieldTrip software to the medial cingulate gyrus that was smaller on incongruent than congruent trials and was significantly influenced by the recruitment of control processes following previous-trial emotional conflict (i.e., there was significant conflict adaptation in the ERPs). Results show that a face-only paradigm may be sufficient to elicit emotional conflict and suggest a system for rapidly detecting conflicting emotional stimuli and subsequently adjusting control resources, similar to cognitive conflict detection processes, when using conflicting facial expressions without words. PMID:24073278

Time course of word production in fast and slow speakers: a high density ERP topographic study.

PubMed

Laganaro, Marina; Valente, Andrea; Perret, Cyril

2012-02-15

The transformation of an abstract concept into an articulated word is achieved through a series of encoding processes, which time course has been repeatedly investigated in the psycholinguistic and neuroimaging literature on single word production. The estimates of the time course issued from previous investigations represent the timing of process duration for mean processing speed: as production speed varies significantly across speakers, a crucial question is how the timing of encoding processing varies with speed. Here we investigated whether between-subjects variability in the speed of speech production is distributed along all encoding processes or if it is accounted for by a specific processing stage. We analysed event-related electroencephalographical (ERP) correlates during overt picture naming in 45 subjects divided into three speed subgroups according to their production latencies. Production speed modulated waveform amplitudes in the time window ranging from about 200 to 350 ms after picture presentation and the duration of a stable electrophysiological spatial configuration in the same time period. The remaining time windows from picture onset to 200 ms before articulation were unaffected by speed. By contrast, the manipulation of a psycholinguistic variable, word age-of-acquisition, modulated ERPs in all speed subgroups in a different and later time period, starting at around 400 ms after picture presentation, associated with phonological encoding processes. These results indicate that the between-subject variability in the speed of single word production is principally accounted for by the timing of a stable electrophysiological activity in the 200-350 ms time period, presumably associated with lexical selection. Copyright © 2011 Elsevier Inc. All rights reserved.

Adaptation to emotional conflict: evidence from a novel face emotion paradigm.

PubMed

Clayson, Peter E; Larson, Michael J

2013-01-01

The preponderance of research on trial-by-trial recruitment of affective control (e.g., conflict adaptation) relies on stimuli wherein lexical word information conflicts with facial affective stimulus properties (e.g., the face-Stroop paradigm where an emotional word is overlaid on a facial expression). Several studies, however, indicate different neural time course and properties for processing of affective lexical stimuli versus affective facial stimuli. The current investigation used a novel task to examine control processes implemented following conflicting emotional stimuli with conflict-inducing affective face stimuli in the absence of affective words. Forty-one individuals completed a task wherein the affective-valence of the eyes and mouth were either congruent (happy eyes, happy mouth) or incongruent (happy eyes, angry mouth) while high-density event-related potentials (ERPs) were recorded. There was a significant congruency effect and significant conflict adaptation effects for error rates. Although response times (RTs) showed a significant congruency effect, the effect of previous-trial congruency on current-trial RTs was only present for current congruent trials. Temporospatial principal components analysis showed a P3-like ERP source localized using FieldTrip software to the medial cingulate gyrus that was smaller on incongruent than congruent trials and was significantly influenced by the recruitment of control processes following previous-trial emotional conflict (i.e., there was significant conflict adaptation in the ERPs). Results show that a face-only paradigm may be sufficient to elicit emotional conflict and suggest a system for rapidly detecting conflicting emotional stimuli and subsequently adjusting control resources, similar to cognitive conflict detection processes, when using conflicting facial expressions without words.

Using EEG To Detect and Monitor Mental Fatigue

NASA Technical Reports Server (NTRS)

Montgomery, Leslie; Luna, Bernadette; Trejo, Leonard J.; Montgomery, Richard

2001-01-01

This project aims to develop EEG-based methods for detecting and monitoring mental fatigue. Mental fatigue poses a serious risk, even when performance is not apparently degraded. When such fatigue is associated with sustained performance of a single type of cognitive task it may be related to the metabolic energy required for sustained activation of cortical areas specialized for that task. The objective of this study was to adapt EEG to monitor cortical energy over a long period of performance of a cognitive task. Multielectrode event related potentials (ERPs) were collected every 15 minutes in nine subjects who performed a mental arithmetic task (algebraic sum of four randomly generated negative or positive digits). A new problem was presented on a computer screen 0.5 seconds after each response; some subjects endured for as long as three hours. ERPs were transformed to a quantitative measure of scalp electrical field energy. The average energy level at electrode P3 (near the left angular gyrus), 100-300 msec latency, was compared over the series of ERPs. For most subjects, scalp energy density at P3 gradually fell over the period of task performance and dramatically increased just before the subject was unable to continue the task. This neural response can be simulated for individual subjects using, a differential equation model in which it is assumed that the mental arithmetic task requires a commitment of metabolic energy that would otherwise be used for brain activities that are temporarily neglected. Their cumulative neglect eventually requires a reallocation of energy away from the mental arithmetic task.

Patient satisfaction with the use of an enhanced recovery programme for primary arthroplasty

PubMed Central

Phillips, S; Parker, M; Carrannante, J; Hearth, MW

2013-01-01

Introduction Enhanced recovery programmes (ERPs) are increasingly being used for arthroplasty. One of the core aims of an ERP is to improve the quality of patient experience. However, there is currently no published evaluation of patient satisfaction in relation to this new programme of care within orthopaedic surgery. The aim of this study was to compare the ERP against the standard care programme (SCP) at one centre. Methods A satisfaction survey addressing patient opinions on the key objectives of the ERP was conducted by telephone, using a set script. Of the 226 patients contacted, 143 (63.3%) responded (69 from the ERP and 74 from the SCP). Of the respondents, 71 received a total hip arthroplasty and 72 a total knee arthroplasty. Patients were contacted at a mean time from operation to survey of 27.2 weeks. They were asked to rate satisfaction on a five-point scale and complete the EQ-5D™ health questionnaire (EuroQol, Rotterdam, Netherlands) to measure healthcare outcomes. Results The mean patient satisfaction score of 4.07 for speed of recovery in the ERP group was significantly higher than the SCP group’s score of 3.68 (p=0.037). Adjusting for the preoperative health score, the postoperative health score was higher for ERP patients at 74.1 compared with 64.7 for SCP patients (p=0.0029). Furthermore, the percentage of patients who had a better than expected recovery was significantly greater in the ERP group at 85.5% compared with 58.1% (p=0.0004) in the SCP group. Conclusions We believe that the previously established reduction in length of hospital stay delivered by ERPs is not achieved at the expense of the patient’s experience. PMID:24165340

Patient satisfaction with the use of an enhanced recovery programme for primary arthroplasty.

PubMed

Machin, J T; Phillips, S; Parker, M; Carrannante, J; Hearth, M W

2013-11-01

Enhanced recovery programmes (ErPs) are increasingly being used for arthroplasty. One of the core aims of an ErP is to improve the quality of patient experience. However, there is currently no published evaluation of patient satisfaction in relation to this new programme of care within orthopaedic surgery. The aim of this study was to compare the ErP against the standard care programme (SCP) at one centre. A satisfaction survey addressing patient opinions on the key objectives of the ErP was conducted by telephone, using a set script. Of the 226 patients contacted, 143 (63.3%) responded (69 from the ErP and 74 from the SCP). Of the respondents, 71 received a total hip arthroplasty and 72 a total knee arthroplasty. Patients were contacted at a mean time from operation to survey of 27.2 weeks. They were asked to rate satisfaction on a five-point scale and complete the EQ-5D™ health questionnaire (EuroQol, rotterdam, Netherlands) to measure healthcare outcomes. The mean patient satisfaction score of 4.07 for speed of recovery in the ErP group was significantly higher than the SCP group's score of 3.68 (p=0.037). Adjusting for the preoperative health score, the postoperative health score was higher for ErP patients at 74.1 compared with 64.7 for SCP patients (p=0.0029). Furthermore, the percentage of patients who had a better than expected recovery was significantly greater in the ErP group at 85.5% compared with 58.1% (p=0.0004) in the SCP group. We believe that the previously established reduction in length of hospital stay delivered by ErPs is not achieved at the expense of the patient's experience.

P300-based brain-computer interface (BCI) event-related potentials (ERPs): People with amyotrophic lateral sclerosis (ALS) vs. age-matched controls.

PubMed

McCane, Lynn M; Heckman, Susan M; McFarland, Dennis J; Townsend, George; Mak, Joseph N; Sellers, Eric W; Zeitlin, Debra; Tenteromano, Laura M; Wolpaw, Jonathan R; Vaughan, Theresa M

2015-11-01

Brain-computer interfaces (BCIs) aimed at restoring communication to people with severe neuromuscular disabilities often use event-related potentials (ERPs) in scalp-recorded EEG activity. Up to the present, most research and development in this area has been done in the laboratory with young healthy control subjects. In order to facilitate the development of BCI most useful to people with disabilities, the present study set out to: (1) determine whether people with amyotrophic lateral sclerosis (ALS) and healthy, age-matched volunteers (HVs) differ in the speed and accuracy of their ERP-based BCI use; (2) compare the ERP characteristics of these two groups; and (3) identify ERP-related factors that might enable improvement in BCI performance for people with disabilities. Sixteen EEG channels were recorded while people with ALS or healthy age-matched volunteers (HVs) used a P300-based BCI. The subjects with ALS had little or no remaining useful motor control (mean ALS Functional Rating Scale-Revised 9.4 (±9.5SD) (range 0-25)). Each subject attended to a target item as the items in a 6×6 visual matrix flashed. The BCI used a stepwise linear discriminant function (SWLDA) to determine the item the user wished to select (i.e., the target item). Offline analyses assessed the latencies, amplitudes, and locations of ERPs to the target and non-target items for people with ALS and age-matched control subjects. BCI accuracy and communication rate did not differ significantly between ALS users and HVs. Although ERP morphology was similar for the two groups, their target ERPs differed significantly in the location and amplitude of the late positivity (P300), the amplitude of the early negativity (N200), and the latency of the late negativity (LN). The differences in target ERP components between people with ALS and age-matched HVs are consistent with the growing recognition that ALS may affect cortical function. The development of BCIs for use by this population may begin with studies in HVs but also needs to include studies in people with ALS. Their differences in ERP components may affect the selection of electrode montages, and might also affect the selection of presentation parameters (e.g., matrix design, stimulation rate). P300-based BCI performance in people severely disabled by ALS is similar to that of age-matched control subjects. At the same time, their ERP components differ to some degree from those of controls. Attention to these differences could contribute to the development of BCIs useful to those with ALS and possibly to others with severe neuromuscular disabilities. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Implementation of enterprise resource planning systems: a user perspective

NASA Astrophysics Data System (ADS)

Reitsma, E.; Hilletofth, P.; Mukhtar, U.

2018-04-01

The purpose of this study is to evaluate critical success factors (CSFs) for the implementation of an enterprise resource planning (ERP) system from a user perspective. Users play a vital role when implementing an ERP system, but their perspective has been neglected in the literature. A better understanding of their perspective promises to contribute to the design of more effective ERP systems, its implementation, and management. In order to identify the user perspective, a survey was conducted within three Pakistani companies that recently have implemented a new ERP system. The questionnaire was developed based on thirteen CSFs deduced from literature. Based on each CSF’s level of importance, they are ranked in order of importance and divided into three groups: most important, important and not important. Findings reveal that users believe that management should prioritize the following four CSFs when implementing an ERP system: education and training, strategic decision-making, communication, and business process alignment.

Comprehending how visual context influences incremental sentence processing: insights from ERPs and picture-sentence verification

PubMed Central

Knoeferle, Pia; Urbach, Thomas P.; Kutas, Marta

2010-01-01

To re-establish picture-sentence verification – discredited possibly for its over-reliance on post-sentence response time (RT) measures - as a task for situated comprehension, we collected event-related brain potentials (ERPs) as participants read a subject-verb-object sentence, and RTs indicating whether or not the verb matched a previously depicted action. For mismatches (vs matches), speeded RTs were longer, verb N400s over centro-parietal scalp larger, and ERPs to the object noun more negative. RTs (congruence effect) correlated inversely with the centro-parietal verb N400s, and positively with the object ERP congruence effects. Verb N400s, object ERPs, and verbal working memory scores predicted more variance in RT effects (50%) than N400s alone. Thus, (1) verification processing is not all post-sentence; (2) simple priming cannot account for these results; and (3) verification tasks can inform studies of situated comprehension. PMID:20701712

Affective picture processing: An integrative review of ERP findings

PubMed Central

Olofsson, Jonas K.; Nordin, Steven; Sequeira, Henrique; Polich, John

2008-01-01

The review summarizes and integrates findings from 40 years of event-related potential (ERP) studies using pictures that differ in valence (unpleasant-to-pleasant) and arousal (low-to-high) and that are used to elicit emotional processing. Affective stimulus factors primarily modulate ERP component amplitude, with little change in peak latency observed. Arousal effects are consistently obtained, and generally occur at longer latencies. Valence effects are inconsistently reported at several latency ranges, including very early components. Some affective ERP modulations vary with recording methodology, stimulus factors, as well as task-relevance and emotional state. Affective ERPs have been linked theoretically to attention orientation for unpleasant pictures at earlier components (< 300 ms). Enhanced stimulus processing has been associated with memory encoding for arousing pictures of assumed intrinsic motivational relevance, with task-induced differences contributing to emotional reactivity at later components (> 300 ms). Theoretical issues, stimulus factors, task demands, and individual differences are discussed. PMID:18164800

Introducing an enhanced recovery programme to an established totally intracorporeal robot-assisted radical cystectomy service.

PubMed

Collins, Justin W; Adding, Christofer; Hosseini, Abolfazl; Nyberg, Tommy; Pini, Giovannalberto; Dey, Linda; Wiklund, Peter N

2016-01-01

The aim of this study was to assess the effect of introducing an enhanced recovery programme (ERP) to an established robot-assisted radical cystectomy (RARC) service. Data were prospectively collected on 221 consecutive patients undergoing totally intracorporeal RARC between December 2003 and May 2014. The ERP was specifically designed to support an evolving RARC service, where increasing proportions of patients requiring radical cystectomy underwent RARC. Patient demographics and outcomes before and after implementation of the ERP were compared. The primary endpoint was length of stay (LOS). Secondary outcomes included age, American Society of Anesthesiologists (ASA) score, preoperative staging, operative time, complications and readmissions. Differences in outcomes between patients before and after implementation of ERP were tested with the Jonckheere-Terpstra trend test and quantile regression with backward selection. Following implementation of the ERP, the demographics of the patients (n = 135) changed, with median age increasing from 66 to 70 years (p < 0.01), higher ASA grade (p < 0.001), higher preoperative stage cancer (pT ≥ 2, p < 0.05) and increased likelihood of undergoing an ileal conduit diversion (p < 0.001). Median LOS before ERP was 9 days [interquartile range (IQR) 8-13 days] and after ERP was 8 days (IQR 6-10 days) (p < 0.001). ASA grade and neoadjuvant chemotherapy also affected LOS (p < 0.05 and p < 0.01, respectively). There was no significant difference in 30 day complication rates, readmission rates or 90 day mortality, with 59% experiencing complications before ERP implementation and 57% after implementation. The majority of complications were low grade. Patient demographics changed as the RARC service evolved from selected patients to a general service. Despite worsening demographics, LOS decreased following ERP implementation. This evidence-based ERP safely standardized perioperative care, resulting in decreased LOS and decreased variability in LOS.

Episodic acidification of small streams in the northeastern united states: episodic response project

USGS Publications Warehouse

Wigington, P.J.; Baker, J.P.; DeWalle, David R.; Kretser, W.A.; Murdoch, Peter S.; Simonin, H.A.; Van Sickle, J.; Mcdowell, M.K.; Peck, D.V.; Barchet, W.R.

1996-01-01

The Episodic Response Project (ERP) was an interdisciplinary study designed to address uncertainties about the occurrence, nature, and biological effects of episodic acidification of streams in the northeastern United States. The ERP research consisted of intensive studies of the chemistry and biological effects of episodes in 13 streams draining forested watersheds in the three study regions: the Northern Appalachian region of Pennsylvania and the Catskill and Adirondack Mountains of New York. Wet deposition was measured in each of the three study regions. Using automated instruments and samplers, discharge and chemistry of each stream was monitored intensively from fall 1988 through spring 1990. Biological studies focused on brook trout and native forage fish. Experimental approaches included in situ bioassays, radio transmitter studies of fish movement, and fish population studies. This paper provides an overview of the ERP, describes the methodology used in hydrologic and water chemistry components of the study, and summarizes the characteristics of the study sites, including the climatic and deposition conditions during the ERP and the general chemical characteristics of the study streams.

The influence of caffeine on sustained attention: an ERP study.

PubMed

Ruijter, J; Lorist, M M; Snel, J; De Ruiter, M B

2000-05-01

The present study investigated the effects of caffeine on sustained attention by measuring concentration and fatigue. Event-related potentials (ERPs) and behavioral measures were recorded from 12 participants who worked continuously for approximately 10 min in a self-paced reaction task under conditions of both caffeine (250 mg) and placebo. The ERP data revealed more positive frontal P2 and parietal P3 components in the caffeine condition. However, a combination of different indices of the behavioral data did not reveal any effects of caffeine intake. These results suggest that caffeine increases arousal, thereby reducing fatigue, as was observed in the ERP results. A probable explanation for the absence of any effects of caffeine in the behavioral data can be found in the demanding properties of the task that was used, thereby supporting evidence for more pronounced effects of caffeine in suboptimal conditions. In addition, these results appeal for an increase in the use of ERPs in drug research, in order to discover possible effects on the brain which do not necessarily result in behavioral changes.

The Complex Pre-Execution Stage of Auditory Cognitive Control: ERPs Evidence from Stroop Tasks

PubMed Central

Yu, Bo; Wang, Xunda; Ma, Lin; Li, Liang; Li, Haifeng

2015-01-01

Cognitive control has been extensively studied from Event-Related Potential (ERP) point of view in visual modality using Stroop paradigms. Little work has been done in auditory Stroop paradigms, and inconsistent conclusions have been reported, especially on the conflict detection stage of cognitive control. This study investigated the early ERP components in an auditory Stroop paradigm, during which participants were asked to identify the volume of spoken words and ignore the word meanings. A series of significant ERP components were revealed that distinguished incongruent and congruent trials: two declined negative polarity waves (the N1 and the N2) and three declined positive polarity wave (the P1, the P2 and the P3) over the fronto-central area for the incongruent trials. These early ERP components imply that both a perceptual stage and an identification stage exist in the auditory Stroop effect. A 3-stage cognitive control model was thus proposed for a more detailed description of the human cognitive control mechanism in the auditory Stroop tasks. PMID:26368570

A Regulatory Circuit Composed of a Transcription Factor, IscR, and a Regulatory RNA, RyhB, Controls Fe-S Cluster Delivery.

PubMed

Mandin, Pierre; Chareyre, Sylvia; Barras, Frédéric

2016-09-20

Fe-S clusters are cofactors conserved through all domains of life. Once assembled by dedicated ISC and/or SUF scaffolds, Fe-S clusters are conveyed to their apo-targets via A-type carrier proteins (ATCs). Escherichia coli possesses four such ATCs. ErpA is the only ATC essential under aerobiosis. Recent studies reported a possible regulation of the erpA mRNA by the small RNA (sRNA) RyhB, which controls the expression of many genes under iron starvation. Surprisingly, erpA has not been identified in recent transcriptomic analysis of the iron starvation response, thus bringing into question the actual physiological significance of the putative regulation of erpA by RyhB. Using an sRNA library, we show that among 26 sRNAs, only RyhB represses the expression of an erpA-lacZ translational fusion. We further demonstrate that this repression occurs during iron starvation. Using mutational analysis, we show that RyhB base pairs to the erpA mRNA, inducing its disappearance. In addition, IscR, the master regulator of Fe-S homeostasis, represses expression of erpA at the transcriptional level when iron is abundant, but depleting iron from the medium alleviates this repression. The conjunction of transcriptional derepression by IscR and posttranscriptional repression by RyhB under Fe-limiting conditions is best described as an incoherent regulatory circuit. This double regulation allows full expression of erpA at iron concentrations for which Fe-S biogenesis switches from the ISC to the SUF system. We further provide evidence that this regulatory circuit coordinates ATC usage to iron availability. Regulatory small RNAs (sRNAs) have emerged as major actors in the control of gene expression in the last few decades. Relatively little is known about how these regulators interact with classical transcription factors to coordinate genetic responses. We show here how an sRNA, RyhB, and a transcription factor, IscR, regulate expression of an essential gene, erpA, in the bacterium E. coli ErpA is involved in the biogenesis of Fe-S clusters, an important class of cofactors involved in a plethora of cellular reactions. Interestingly, we show that RyhB and IscR repress expression of erpA under opposite conditions in regard to iron concentration, forming a regulatory circuit called an "incoherent network." This incoherent network serves to maximize expression of erpA at iron concentrations where it is most needed. Altogether, our study paves the way for a better understanding of mixed regulatory networks composed of RNAs and transcription factors. Copyright © 2016 Mandin et al.

Enhanced recovery program (ERP) in major laryngeal surgery: building a protocol and testing its feasibility.

PubMed

Gemma, M; Toma, S; Lira Luce, F; Beretta, L; Braga, M; Bussi, M

2017-12-01

Enhanced recovery programs (ERP) represent a multimodal approach to perioperative patient care. The benefits of ERP are well demonstrated in colorectal surgery and Enhanced Recovery After Surgery (ERAS®) programs, that epitomise the ERP concept, have being introduced in different specialties, including vascular, gastric, pancreatic, urogynecologic and orthopaedic surgery. However, no ERP has been proposed for head and neck surgery. We developed an expert-opinion-based ERP for laryngeal surgery based on the key principles of colorectal surgery ERAS®. Twenty-four patients undergoing major laryngeal surgery (total and partial laryngectomies or surgical removal of oropharyngeal tumour with muscle flap reconstruction) were treated according to such an ERP protocol, which differed under several respects from our previous standard practice (described in 70 consecutive patients who underwent major laryngeal surgery before ERP implementation. The adherence rate to the different ERP items is reported. Adherence to ERP items was high. Nutritional assessment, antibiotic prophylaxis, postoperative nausea and vomit (PONV) prophylaxis and postoperative speech therapy targets were applied as required in 100% of cases. Some ERP items (antibiotic prophylaxis, intraoperative infusion rate, and postoperative speech therapy) were already frequently implemented before ERP adoption. Postoperative medical complications occurred in 8.3% of patients. Our expert opinion-based ERP protocol for major laryngeal surgery proved feasible. The degree of benefit deriving from its implementation has yet to be assessed. © Copyright by Società Italiana di Otorinolaringologia e Chirurgia Cervico-Facciale, Rome, Italy.

Validation of the Emotiv EPOC® EEG gaming system for measuring research quality auditory ERPs

PubMed Central

Mousikou, Petroula; Mahajan, Yatin; de Lissa, Peter; Thie, Johnson; McArthur, Genevieve

2013-01-01

Background. Auditory event-related potentials (ERPs) have proved useful in investigating the role of auditory processing in cognitive disorders such as developmental dyslexia, specific language impairment (SLI), attention deficit hyperactivity disorder (ADHD), schizophrenia, and autism. However, laboratory recordings of auditory ERPs can be lengthy, uncomfortable, or threatening for some participants – particularly children. Recently, a commercial gaming electroencephalography (EEG) system has been developed that is portable, inexpensive, and easy to set up. In this study we tested if auditory ERPs measured using a gaming EEG system (Emotiv EPOC®, www.emotiv.com) were equivalent to those measured by a widely-used, laboratory-based, research EEG system (Neuroscan). Methods. We simultaneously recorded EEGs with the research and gaming EEG systems, whilst presenting 21 adults with 566 standard (1000 Hz) and 100 deviant (1200 Hz) tones under passive (non-attended) and active (attended) conditions. The onset of each tone was marked in the EEGs using a parallel port pulse (Neuroscan) or a stimulus-generated electrical pulse injected into the O1 and O2 channels (Emotiv EPOC®). These markers were used to calculate research and gaming EEG system late auditory ERPs (P1, N1, P2, N2, and P3 peaks) and the mismatch negativity (MMN) in active and passive listening conditions for each participant. Results. Analyses were restricted to frontal sites as these are most commonly reported in auditory ERP research. Intra-class correlations (ICCs) indicated that the morphology of the research and gaming EEG system late auditory ERP waveforms were similar across all participants, but that the research and gaming EEG system MMN waveforms were only similar for participants with non-noisy MMN waveforms (N = 11 out of 21). Peak amplitude and latency measures revealed no significant differences between the size or the timing of the auditory P1, N1, P2, N2, P3, and MMN peaks. Conclusions. Our findings suggest that the gaming EEG system may prove a valid alternative to laboratory ERP systems for recording reliable late auditory ERPs (P1, N1, P2, N2, and the P3) over the frontal cortices. In the future, the gaming EEG system may also prove useful for measuring less reliable ERPs, such as the MMN, if the reliability of such ERPs can be boosted to the same level as late auditory ERPs. PMID:23638374

Validation of the Emotiv EPOC(®) EEG gaming system for measuring research quality auditory ERPs.

PubMed

Badcock, Nicholas A; Mousikou, Petroula; Mahajan, Yatin; de Lissa, Peter; Thie, Johnson; McArthur, Genevieve

2013-01-01

Background. Auditory event-related potentials (ERPs) have proved useful in investigating the role of auditory processing in cognitive disorders such as developmental dyslexia, specific language impairment (SLI), attention deficit hyperactivity disorder (ADHD), schizophrenia, and autism. However, laboratory recordings of auditory ERPs can be lengthy, uncomfortable, or threatening for some participants - particularly children. Recently, a commercial gaming electroencephalography (EEG) system has been developed that is portable, inexpensive, and easy to set up. In this study we tested if auditory ERPs measured using a gaming EEG system (Emotiv EPOC(®), www.emotiv.com) were equivalent to those measured by a widely-used, laboratory-based, research EEG system (Neuroscan). Methods. We simultaneously recorded EEGs with the research and gaming EEG systems, whilst presenting 21 adults with 566 standard (1000 Hz) and 100 deviant (1200 Hz) tones under passive (non-attended) and active (attended) conditions. The onset of each tone was marked in the EEGs using a parallel port pulse (Neuroscan) or a stimulus-generated electrical pulse injected into the O1 and O2 channels (Emotiv EPOC(®)). These markers were used to calculate research and gaming EEG system late auditory ERPs (P1, N1, P2, N2, and P3 peaks) and the mismatch negativity (MMN) in active and passive listening conditions for each participant. Results. Analyses were restricted to frontal sites as these are most commonly reported in auditory ERP research. Intra-class correlations (ICCs) indicated that the morphology of the research and gaming EEG system late auditory ERP waveforms were similar across all participants, but that the research and gaming EEG system MMN waveforms were only similar for participants with non-noisy MMN waveforms (N = 11 out of 21). Peak amplitude and latency measures revealed no significant differences between the size or the timing of the auditory P1, N1, P2, N2, P3, and MMN peaks. Conclusions. Our findings suggest that the gaming EEG system may prove a valid alternative to laboratory ERP systems for recording reliable late auditory ERPs (P1, N1, P2, N2, and the P3) over the frontal cortices. In the future, the gaming EEG system may also prove useful for measuring less reliable ERPs, such as the MMN, if the reliability of such ERPs can be boosted to the same level as late auditory ERPs.

Spatiotemporal patterns of ERP based on combined ICA-LORETA analysis

NASA Astrophysics Data System (ADS)

Zhang, Jiacai; Guo, Taomei; Xu, Yaqin; Zhao, Xiaojie; Yao, Li

2007-03-01

In contrast to the FMRI methods widely used up to now, this method try to understand more profoundly how the brain systems work under sentence processing task map accurately the spatiotemporal patterns of activity of the large neuronal populations in the human brain from the analysis of ERP data recorded on the brain scalp. In this study, an event-related brain potential (ERP) paradigm to record the on-line responses to the processing of sentences is chosen as an example. In order to give attention to both utilizing the ERPs' temporal resolution of milliseconds and overcoming the insensibility of cerebral location ERP sources, we separate these sources in space and time based on a combined method of independent component analysis (ICA) and low-resolution tomography (LORETA) algorithms. ICA blindly separate the input ERP data into a sum of temporally independent and spatially fixed components arising from distinct or overlapping brain or extra-brain sources. And then the spatial maps associated with each ICA component are analyzed, with use of LORETA to uniquely locate its cerebral sources throughout the full brain according to the assumption that neighboring neurons are simultaneously and synchronously activated. Our results show that the cerebral computation mechanism underlies content words reading is mediated by the orchestrated activity of several spatially distributed brain sources located in the temporal, frontal, and parietal areas, and activate at distinct time intervals and are grouped into different statistically independent components. Thus ICA-LORETA analysis provides an encouraging and effective method to study brain dynamics from ERP.

Distinguishing Neurocognitive Processes Reflected by P600 Effects: Evidence from ERPs and Neural Oscillations

PubMed Central

Regel, Stefanie; Meyer, Lars; Gunter, Thomas C.

2014-01-01

Research on language comprehension using event-related potentials (ERPs) reported distinct ERP components reliably related to the processing of semantic (N400) and syntactic information (P600). Recent ERP studies have challenged this well-defined distinction by showing P600 effects for semantic and pragmatic anomalies. So far, it is still unresolved whether the P600 reflects specific or rather common processes. The present study addresses this question by investigating ERPs in response to a syntactic and pragmatic (irony) manipulation, as well as a combined syntactic and pragmatic manipulation. For the syntactic condition, a morphosyntactic violation was applied, whereas for the pragmatic condition, such as “That is rich”, either an ironic or literal interpretation was achieved, depending on the prior context. The ERPs at the critical word showed a LAN-P600 pattern for syntactically incorrect sentences relative to correct ones. For ironic compared to literal sentences, ERPs showed a P200 effect followed by a P600 component. In comparison of the syntax-related P600 to the irony-related P600, distributional differences were found. Moreover, for the P600 time window (i.e., 500–900 ms), different changes in theta power between the syntax and pragmatics effects were found, suggesting that different patterns of neural activity contributed to each respective effect. Thus, both late positivities seem to be differently sensitive to these two types of linguistic information, and might reflect distinct neurocognitive processes, such as reanalysis of the sentence structure versus pragmatic reanalysis. PMID:24844290

Neuronal generator patterns of olfactory event-related brain potentials in schizophrenia.

PubMed

Kayser, Jürgen; Tenke, Craig E; Malaspina, Dolores; Kroppmann, Christopher J; Schaller, Jennifer D; Deptula, Andrew; Gates, Nathan A; Harkavy-Friedman, Jill M; Gil, Roberto; Bruder, Gerard E

2010-11-01

To better characterize neurophysiologic processes underlying olfactory dysfunction in schizophrenia, nose-referenced 30-channel electroencephalogram was recorded from 32 patients and 35 healthy adults (18 and 18 male) during detection of hydrogen sulfide (constant-flow olfactometer, 200 ms unirhinal exposure). Event-related potentials (ERPs) were transformed to reference-free current source density (CSD) waveforms and analyzed by unrestricted Varimax-PCA. Participants indicated when they perceived a high (10 ppm) or low (50% dilution) odor concentration. Patients and controls did not differ in detection of high (23% misses) and low (43%) intensities and also had similar olfactory ERP waveforms. CSDs showed a greater bilateral frontotemporal N1 sink (305 ms) and mid-parietal P2 source (630 ms) for high than low intensities. N1 sink and P2 source were markedly reduced in patients for high intensity stimuli, providing further neurophysiological evidence of olfactory dysfunction in schizophrenia. Copyright © 2010 Society for Psychophysiological Research.

Syntax, concepts, and logic in the temporal dynamics of language comprehension: evidence from event-related potentials.

PubMed

Steinhauer, Karsten; Drury, John E; Portner, Paul; Walenski, Matthew; Ullman, Michael T

2010-05-01

Logic has been intertwined with the study of language and meaning since antiquity, and such connections persist in present day research in linguistic theory (formal semantics) and cognitive psychology (e.g., studies of human reasoning). However, few studies in cognitive neuroscience have addressed logical dimensions of sentence-level language processing, and none have directly compared these aspects of processing with syntax and lexical/conceptual-semantics. We used ERPs to examine a violation paradigm involving "Negative Polarity Items" or NPIs (e.g., ever/any), which are sensitive to logical/truth-conditional properties of the environments in which they occur (e.g., presence/absence of negation in: John hasn't ever been to Paris, versus: John has *ever been to Paris). Previous studies examining similar types of contrasts found a mix of effects on familiar ERP components (e.g., LAN, N400, P600). We argue that their experimental designs and/or analyses were incapable of separating which effects are connected to NPI-licensing violations proper. Our design enabled statistical analyses teasing apart genuine violation effects from independent effects tied solely to lexical/contextual factors. Here unlicensed NPIs elicited a late P600 followed in onset by a late left anterior negativity (or "L-LAN"), an ERP profile which has also appeared elsewhere in studies targeting logical semantics. Crucially, qualitatively distinct ERP-profiles emerged for syntactic and conceptual semantic violations which we also tested here. We discuss how these findings may be linked to previous findings in the ERP literature. Apart from methodological recommendations, we suggest that the study of logical semantics may aid advancing our understanding of the underlying neurocognitive etiology of ERP components. 2010 Elsevier Ltd. All rights reserved.

A comparative study on long-term evoked auditory and visual potential responses between Schizophrenic patients and normal subjects

PubMed Central

2011-01-01

Background The electrical signals measuring method is recommended to examine the relationship between neuronal activities and measure with the event related potentials (ERPs) during an auditory and a visual oddball paradigm between schizophrenic patients and normal subjects. The aim of this study is to discriminate the activation changes of different stimulations evoked by auditory and visual ERPs between schizophrenic patients and normal subjects. Methods Forty-three schizophrenic patients were selected as experimental group patients, and 40 healthy subjects with no medical history of any kind of psychiatric diseases, neurological diseases, or drug abuse, were recruited as a control group. Auditory and visual ERPs were studied with an oddball paradigm. All the data were analyzed by SPSS statistical software version 10.0. Results In the comparative study of auditory and visual ERPs between the schizophrenic and healthy patients, P300 amplitude at Fz, Cz, and Pz and N100, N200, and P200 latencies at Fz, Cz, and Pz were shown significantly different. The cognitive processing reflected by the auditory and the visual P300 latency to rare target stimuli was probably an indicator of the cognitive function in schizophrenic patients. Conclusions This study shows the methodology of application of auditory and visual oddball paradigm identifies task-relevant sources of activity and allows separation of regions that have different response properties. Our study indicates that there may be slowness of automatic cognitive processing and controlled cognitive processing of visual ERPs compared to auditory ERPs in schizophrenic patients. The activation changes of visual evoked potentials are more regionally specific than auditory evoked potentials. PMID:21542917

SYNTAX, CONCEPTS, AND LOGIC IN THE TEMPORAL DYNAMICS OF LANGUAGE COMPREHENSION: EVIDENCE FROM EVENT RELATED POTENTIALS

PubMed Central

Steinhauer, Karsten; Drury, John E.; Portner, Paul; Walenski, Matthew; Ullman, Michael T.

2010-01-01

Logic has been intertwined with the study of language and meaning since antiquity, and such connections persist in present day research in linguistic theory (formal semantics) and cognitive psychology (e.g., studies of human reasoning). However, few studies in cognitive neuroscience have addressed logical dimensions of sentence-level language processing, and none have directly compared these aspects of processing with syntax and lexical/conceptual-semantics. We used ERPs to examine a violation paradigm involving “Negative Polarity Items” or NPIs (e.g., ever/any), which are sensitive to logical/truth-conditional properties of the environments in which they occur (e.g., presence/absence of negation in: John hasn’t ever been to Paris, versus: John has *ever been to Paris). Previous studies examining similar types of contrasts found a mix of effects on familiar ERP components (e.g., LAN, N400, P600). We argue that their experimental designs and/or analyses were incapable of separating which effects are connected to NPI-licensing violations proper. Our design enabled statistical analyses teasing apart genuine violation effects from independent effects tied solely to lexical/contextual factors. Here unlicensed NPIs elicited a late P600 followed in onset by a late left anterior negativity (or “L-LAN”), an ERP profile which has also appeared elsewhere in studies targeting logical semantics. Crucially, qualitatively distinct ERP-profiles emerged for syntactic and conceptual semantic violations which we also tested here. We discuss how these findings may be linked to previous findings in the ERP literature. Apart from methodological recommendations, we suggest that the study of logical semantics may aid advancing our understanding of the underlying neurocognitive etiology of ERP components. PMID:20138065

Using Family-Based Exposure With Response Prevention to Treat Obsessive-Compulsive Disorder in Young Children: A Case Study.

PubMed

Herren, Jenny; Freeman, Jennifer; Garcia, Abbe

2016-11-01

Cognitive-behavioral therapy (CBT) using exposure with response prevention (ERP) is the treatment of choice for obsessive-compulsive disorder (OCD); however, developmental modifications should be considered when treating young children. This article presents a case study illustrating family-based CBT using ERP with a 7-year-old boy. The delivery of ERP for this case was guided by 3 main principles: (a) family involvement with a focus on reducing family accommodation, (b) understanding the functional relation between the client's obsessions and compulsions, and (c) creating conditions to facilitate habituation during exposure. Outcomes for this case indicate significant improvement in functioning and OCD symptoms. Results highlight the importance of family involvement and the applicability of using a function-based habituation framework when delivering ERP to this unique population. © 2016 Wiley Periodicals, Inc.

Assessing Leading ERP-SAP Implementation in Leading Firms in Indonesia

NASA Astrophysics Data System (ADS)

Syaiful, B.; Gunawan, W.

2017-01-01

Enterprise resource planning (ERP) enables to bring critical capabilities to an organisation, however, the implementation of such capabilities is often surrounded with problems. The implementing ERP-SAP in Indonesian enterprises are still facing tremendous challenges with the failure rate can reach more than 80% of the cases. The article examines the common problems faced by the consultants whenever they deal with their clients, from the practical perspectives. The article takes the multiple case studies of the leading enterprises in Indonesia, such as: KS (largest steel producer), GEM (large mining producer), and HS (large retailer), with the aim to identify the root of problems of SAP implementation. The outcome of the study is expected to provide the consultants with the guideline to understand the ERP implementation process in their clients and effective solutions to cope with it.

Clinch River - Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simbeck, D.J.

1997-06-01

Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22-29, 1993, prior to initiation of CR-ERP Phase II Sampling and Analysis activities as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories formore » testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA.« less

ERP Correlates of Encoding Success and Encoding Selectivity in Attention Switching

PubMed Central

Yeung, Nick

2016-01-01

Long-term memory encoding depends critically on effective processing of incoming information. The degree to which participants engage in effective encoding can be indexed in electroencephalographic (EEG) data by studying event-related potential (ERP) subsequent memory effects. The current study investigated ERP correlates of memory success operationalised with two different measures—memory selectivity and global memory—to assess whether previously observed ERP subsequent memory effects reflect focused encoding of task-relevant information (memory selectivity), general encoding success (global memory), or both. Building on previous work, the present study combined an attention switching paradigm—in which participants were presented with compound object-word stimuli and switched between attending to the object or the word across trials—with a later recognition memory test for those stimuli, while recording their EEG. Our results provided clear evidence that subsequent memory effects resulted from selective attentional focusing and effective top-down control (memory selectivity) in contrast to more general encoding success effects (global memory). Further analyses addressed the question of whether successful encoding depended on similar control mechanisms to those involved in attention switching. Interestingly, differences in the ERP correlates of attention switching and successful encoding, particularly during the poststimulus period, indicated that variability in encoding success occurred independently of prestimulus demands for top-down cognitive control. These results suggest that while effects of selective attention and selective encoding co-occur behaviourally their ERP correlates are at least partly dissociable. PMID:27907075

Modafinil improves information processing speed and increases energetic resources for orientation of attention in narcoleptics: double-blind, placebo-controlled ERP studies with low-resolution brain electromagnetic tomography (LORETA).

PubMed

Saletu, Michael; Anderer, Peter; Saletu-Zyhlarz, Gerda Maria; Mandl, Magdalena; Saletu, Bernd; Zeitlhofer, Josef

2009-09-01

Recent neuroimaging studies in narcolepsy discovered significant gray matter loss in the right prefrontal and frontomesial cortex, a critical region for executive processing. In the present study, event-related potential (ERP) low-resolution brain electromagnetic tomography (LORETA) was used to investigate cognition before and after modafinil as compared with placebo. In a double-blind, placebo-controlled cross-over design, 15 patients were treated with a 3-week fixed titration scheme of modafinil and placebo. The Epworth Sleepiness Scale (ESS), Maintenance of Wakefulness Test (MWT) and auditory ERPs (odd-ball paradigm) were obtained before and after the 3 weeks of therapy. Latencies, amplitudes and LORETA sources were determined for standard (N1 and P2) and target (N2 and P300) ERP components. The ESS score improved significantly from 15.4 (+/- 4.0) under placebo to 10.2 (+/- 4.1) under 400mg modafinil (p=0.004). In the MWT, latency to sleep increased nonsignificantly after modafinil treatment (11.9+/-6.9 versus 13.3+/-7.1 min). In the ERP, N2 and P300 latencies were shortened significantly. While ERP amplitudes showed only minor changes, LORETA revealed increased source strengths: for N1 in the left auditory cortex and for P300 in the medial and right dorsolateral prefrontal cortex. LORETA revealed that modafinil improved information processing speed and increased energetic resources in prefrontal cortical regions, which is in agreement with other neuroimaging studies.

A Comprehensive, Competency-Based Education Framework Using Medium-Sized ERP Systems

ERIC Educational Resources Information Center

Scholtz, Brenda; Cilliers, Charmain; Calitz, Andre

2012-01-01

Graduates with industry-relevant ERP competencies are highly sought after. This requirement is due to a dominance of Enterprise Resource Planning (ERP) systems and the positive affect which good quality ERP specialists have on the success rate of ERP system implementation projects. Universities are therefore increasingly pressurised to supply…

7 CFR 1730.28 - Emergency Restoration Plan (ERP).

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Emergency Restoration Plan (ERP). 1730.28 Section... § 1730.28 Emergency Restoration Plan (ERP). (a) Each borrower with an approved RUS electric program loan as of October 12, 2004 shall have a written ERP no later than January 12, 2006. The ERP should be...

False memory and level of processing effect: an event-related potential study.

PubMed

Beato, Maria Soledad; Boldini, Angela; Cadavid, Sara

2012-09-12

Event-related potentials (ERPs) were used to determine the effects of level of processing on true and false memory, using the Deese-Roediger-McDermott (DRM) paradigm. In the DRM paradigm, lists of words highly associated to a single nonpresented word (the 'critical lure') are studied and, in a subsequent memory test, critical lures are often falsely remembered. Lists with three critical lures per list were auditorily presented here to participants who studied them with either a shallow (saying whether the word contained the letter 'o') or a deep (creating a mental image of the word) processing task. Visual presentation modality was used on a final recognition test. True recognition of studied words was significantly higher after deep encoding, whereas false recognition of nonpresented critical lures was similar in both experimental groups. At the ERP level, true and false recognition showed similar patterns: no FN400 effect was found, whereas comparable left parietal and late right frontal old/new effects were found for true and false recognition in both experimental conditions. Items studied under shallow encoding conditions elicited more positive ERP than items studied under deep encoding conditions at a 1000-1500 ms interval. These ERP results suggest that true and false recognition share some common underlying processes. Differential effects of level of processing on true and false memory were found only at the behavioral level but not at the ERP level.

Less precise representation of numerical magnitude in high math-anxious individuals: an ERP study of the size and distance effects.

PubMed

Núñez-Peña, M Isabel; Suárez-Pellicioni, Macarena

2014-12-01

Numerical comparison tasks are widely used to study the mental representation of numerical magnitude. In study, event-related brain potentials (ERPs) were recorded while 26 high math-anxious (HMA) and 27 low math-anxious (LMA) individuals were presented with pairs of single-digit Arabic numbers and were asked to decide which one had the larger numerical magnitude. The size of the numbers and the distance between them were manipulated in order to study the size and the distance effects. The results showed that both distance and size effects were larger for the HMA group. As for ERPs, results showed that the ERP distance effect had larger amplitude for both the size and distance effects in the HMA group than among their LMA counterparts. Since this component has been taken as a marker of the processing of numerical magnitude, this result suggests that HMA individuals have a less precise representation of numerical magnitude. Copyright © 2014 Elsevier B.V. All rights reserved.

Early differential processing of material images: Evidence from ERP classification.

PubMed

Wiebel, Christiane B; Valsecchi, Matteo; Gegenfurtner, Karl R

2014-06-24

Investigating the temporal dynamics of natural image processing using event-related potentials (ERPs) has a long tradition in object recognition research. In a classical Go-NoGo task two characteristic effects have been emphasized: an early task independent category effect and a later task-dependent target effect. Here, we set out to use this well-established Go-NoGo paradigm to study the time course of material categorization. Material perception has gained more and more interest over the years as its importance in natural viewing conditions has been ignored for a long time. In addition to analyzing standard ERPs, we conducted a single trial ERP pattern analysis. To validate this procedure, we also measured ERPs in two object categories (people and animals). Our linear classification procedure was able to largely capture the overall pattern of results from the canonical analysis of the ERPs and even extend it. We replicate the known target effect (differential Go-NoGo potential at frontal sites) for the material images. Furthermore, we observe task-independent differential activity between the two material categories as early as 140 ms after stimulus onset. Using our linear classification approach, we show that material categories can be differentiated consistently based on the ERP pattern in single trials around 100 ms after stimulus onset, independent of the target-related status. This strengthens the idea of early differential visual processing of material categories independent of the task, probably due to differences in low-level image properties and suggests pattern classification of ERP topographies as a strong instrument for investigating electrophysiological brain activity. © 2014 ARVO.

Impact of a colorectal enhanced recovery program implementation on clinical outcomes and institutional costs: A prospective cohort study with retrospective control.

PubMed

Portinari, Mattia; Ascanelli, Simona; Targa, Simone; Dos Santos Valgode, Elisabete Maria; Bonvento, Barbara; Vagnoni, Emidia; Camerani, Stefano; Verri, Marco; Volta, Carlo Alberto; Feo, Carlo V

2018-05-01

The enhanced recovery program for perioperative care of the surgical patient reduces postoperative metabolic response and organ dysfunction, accelerating functional recovery. The aim of this study was to determine the impact on postoperative recovery and cost-effectiveness of implementing a colorectal enhanced recovery program in an Italian academic centre. A prospective series of consecutive patients (N = 100) undergoing elective colorectal resection completing a standardized enhanced recovery program in 2013-2015 (ERP group) was compared to patients (N = 100) operated at the same institution in 2010-2011 (Pre-ERP group) before introducing the program. The exclusion criteria were: >80 years old, ASA score of IV, a stage IV TNM, and diagnosis of inflammatory bowel disease. The primary outcome was hospital length of stay which was used as a proxy of functional recovery. Secondary outcomes included: postoperative complications, 30-day readmission and mortality, protocol adherence, nursing workload, cost-effectiveness, and factors predicting prolonged hospital stay. The ERP group patient satisfaction was also evaluated. Hospital stay was significantly reduced in the ERP versus the Pre-ERP group (4 versus 8 days) as well as nursing workload, with no increase in postoperative complications, 30-day readmission or mortality. ERP group protocol adherence (81%) and patient satisfaction were high. Conventional perioperative protocol was the only independent predictor of prolonged hospital stay. Total mean direct costs per patient were significantly higher in the Pre-ERP versus the ERP group (6796.76 versus 5339.05 euros). Implementing a colorectal enhanced recovery program is feasible, efficient for functional recovery and hospital stay reduction, safe, and cost-effective. High patient satisfaction and nursing workload reduction may also be expected, but high protocol adherence is necessary. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Effects of cue frequency and repetition on prospective memory: an ERP investigation.

PubMed

Wilson, Jennifer; Cutmore, Tim R H; Wang, Ya; Chan, Raymond C K; Shum, David H K

2013-11-01

Prospective memory involves the formation and completion of delayed intentions and is essential for independent living. In this study (n = 33), event-related potentials (ERPs) were used to systematically evaluate the effects of PM cue frequency (10% versus 30%) and PM cue repetition (high versus low) on ERP modulations. PM cues elicited prospective positivity and frontal positivity but not N300, perhaps due to the semantic nature of the task. Results of this study revealed an interesting interaction between PM cue frequency and PM cue repetition for prospective positivity and frontal positivity, highlighting the importance of taking both factors into account when designing future studies. © 2013.

Genetic Mapping of Brain Plasticity Across Development in Williams Syndrome: ERP Markers of Face and Language Processing

PubMed Central

Mills, D. L.; Dai, L.; Fishman, I.; Yam, A.; Appelbaum, L. G.; Galaburda, A.; Bellugi, U.; Korenberg, J. R.

2014-01-01

In Williams Syndrome (WS), a known genetic deletion results in atypical brain function with strengths in face and language processing. We examined how genetic influences on brain activity change with development. In three studies, ERPs from large samples of children, adolescents, and adults with the full genetic deletion for WS were compared to typically developing controls, and two adults with partial deletions for WS. Studies 1 and 2 identified ERP markers of brain plasticity in WS across development. Study 3 suggested that in adults with partial deletions for WS, specific genes may be differentially implicated in face and language processing. PMID:24219698

Competitive Semantic Memory Retrieval: Temporal Dynamics Revealed by Event-Related Potentials

PubMed Central

Hellerstedt, Robin; Johansson, Mikael

2016-01-01

Memories compete for retrieval when they are related to a common retrieval cue. Previous research has shown that retrieval of a target memory may lead to subsequent retrieval-induced forgetting (RIF) of currently irrelevant competing memories. In the present study, we investigated the time course of competitive semantic retrieval and examined the neurocognitive mechanisms underlying RIF. We contrasted two theoretical accounts of RIF by examining a critical aspect of this memory phenomenon, namely the extent to which it depends on successful retrieval of the target memory. Participants first studied category-exemplar word-pairs (e.g. Fruit—Apple). Next, we recorded electrophysiological measures of brain activity while the participants performed a competitive semantic cued-recall task. In this task, the participants were provided with the studied categories but they were instructed to retrieve other unstudied exemplars (e.g. Fruit—Ma__?). We investigated the event-related potential (ERP) correlates of retrieval success by comparing ERPs from successful and failed retrieval trials. To isolate the ERP correlates of continuous retrieval attempts from the ERP correlates of retrieval success, we included an impossible retrieval condition, with incompletable word-stem cues (Drinks—Wy__) and compared it with a non-retrieval presentation baseline condition (Occupation—Dentist). The participants’ memory for all the studied exemplars was tested in the final phase of the experiment. Taken together, the behavioural results suggest that RIF is independent of target retrieval. Beyond investigating the mechanisms underlying RIF, the present study also elucidates the temporal dynamics of semantic cued-recall by isolating the ERP correlates of retrieval attempt and retrieval success. The ERP results revealed that retrieval attempt is reflected in a late posterior negativity, possibly indicating construction of candidates for completing the word-stem cue and retrieval monitoring whereas retrieval success was reflected in an anterior positive slow wave. PMID:26901865

Competitive Semantic Memory Retrieval: Temporal Dynamics Revealed by Event-Related Potentials.

PubMed

Hellerstedt, Robin; Johansson, Mikael

2016-01-01

Memories compete for retrieval when they are related to a common retrieval cue. Previous research has shown that retrieval of a target memory may lead to subsequent retrieval-induced forgetting (RIF) of currently irrelevant competing memories. In the present study, we investigated the time course of competitive semantic retrieval and examined the neurocognitive mechanisms underlying RIF. We contrasted two theoretical accounts of RIF by examining a critical aspect of this memory phenomenon, namely the extent to which it depends on successful retrieval of the target memory. Participants first studied category-exemplar word-pairs (e.g. Fruit-Apple). Next, we recorded electrophysiological measures of brain activity while the participants performed a competitive semantic cued-recall task. In this task, the participants were provided with the studied categories but they were instructed to retrieve other unstudied exemplars (e.g. Fruit-Ma__?). We investigated the event-related potential (ERP) correlates of retrieval success by comparing ERPs from successful and failed retrieval trials. To isolate the ERP correlates of continuous retrieval attempts from the ERP correlates of retrieval success, we included an impossible retrieval condition, with incompletable word-stem cues (Drinks-Wy__) and compared it with a non-retrieval presentation baseline condition (Occupation-Dentist). The participants' memory for all the studied exemplars was tested in the final phase of the experiment. Taken together, the behavioural results suggest that RIF is independent of target retrieval. Beyond investigating the mechanisms underlying RIF, the present study also elucidates the temporal dynamics of semantic cued-recall by isolating the ERP correlates of retrieval attempt and retrieval success. The ERP results revealed that retrieval attempt is reflected in a late posterior negativity, possibly indicating construction of candidates for completing the word-stem cue and retrieval monitoring whereas retrieval success was reflected in an anterior positive slow wave.

Event-related potential indices of workload in a single task paradigm

NASA Technical Reports Server (NTRS)

Horst, R. L.; Munson, R. C.; Ruchkin, D. S.

1984-01-01

Many previous studies of both behavioral and physiological correlates of cognitive workload have burdened subjects with a contrived secondary task in order to assess the workload of a primary task. The present study investigated event-related potential (ERP) indices of workload in a single task paradigm. Subjects monitored changing digital readouts for values that went 'out-of-bounds'. The amplitude of a long-latency positivity in the ERPs elicited by readout changes increased with the number of readouts being monitored. This effect of workload on ERPs is reported, along with plans for additional analyses to address theoretical implications.

Disturbances in Response Inhibition and Emotional Processing as Potential Pathways to Violence in Schizophrenia: A High-Density Event-Related Potential Study.

PubMed

Krakowski, Menahem I; De Sanctis, Pierfilippo; Foxe, John J; Hoptman, Matthew J; Nolan, Karen; Kamiel, Stephanie; Czobor, Pal

2016-07-01

Increased susceptibility to emotional triggers and poor response inhibition are important in the etiology of violence in schizophrenia. Our goal was to evaluate abnormalities in neurophysiological mechanisms underlying response inhibition and emotional processing in violent patients with schizophrenia (VS) and 3 different comparison groups: nonviolent patients (NV), healthy controls (HC) and nonpsychotic violent subjects (NPV). We recorded high-density Event-Related Potentials (ERPs) and behavioral responses during an Emotional Go/NoGo Task in 35 VS, 24 NV, 28 HC and 31 NPV subjects. We also evaluated psychiatric symptoms and impulsivity. The neural and behavioral deficits in violent patients were most pronounced when they were presented with negative emotional stimuli: They responded more quickly than NV when they made commission errors (ie, failure of inhibition), and evidenced N2 increases and P3 decreases. In contrast, NVs showed little change in reaction time or ERP amplitude with emotional stimuli. These N2 and P3 amplitude changes in VSs showed a strong association with greater impulsivity. Besides these group specific changes, VSs shared deficits with NV, mostly N2 reduction, and with violent nonpsychotic subjects, particularly P3 reduction. Negative affective triggers have a strong impact on violent patients with schizophrenia which may have both behavioral and neural manifestations. The resulting activation could interfere with response inhibition. The affective disruption of response inhibition, identified in this study, may index an important pathway to violence in schizophrenia and suggest new modes of treatment. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

An Event-Related Potentials Study of Mental Rotation in Identifying Chemical Structural Formulas

ERIC Educational Resources Information Center

Huang, Chin-Fei; Liu, Chia-Ju

2012-01-01

The purpose of this study was to investigate how mental rotation strategies affect the identification of chemical structural formulas. This study conducted event-related potentials (ERPs) experiments. In addition to the data collected in the ERPs, a Chemical Structure Conceptual Questionnaire and interviews were also admin-istered for data…

Spatial-temporal discriminant analysis for ERP-based brain-computer interface.

PubMed

Zhang, Yu; Zhou, Guoxu; Zhao, Qibin; Jin, Jing; Wang, Xingyu; Cichocki, Andrzej

2013-03-01

Linear discriminant analysis (LDA) has been widely adopted to classify event-related potential (ERP) in brain-computer interface (BCI). Good classification performance of the ERP-based BCI usually requires sufficient data recordings for effective training of the LDA classifier, and hence a long system calibration time which however may depress the system practicability and cause the users resistance to the BCI system. In this study, we introduce a spatial-temporal discriminant analysis (STDA) to ERP classification. As a multiway extension of the LDA, the STDA method tries to maximize the discriminant information between target and nontarget classes through finding two projection matrices from spatial and temporal dimensions collaboratively, which reduces effectively the feature dimensionality in the discriminant analysis, and hence decreases significantly the number of required training samples. The proposed STDA method was validated with dataset II of the BCI Competition III and dataset recorded from our own experiments, and compared to the state-of-the-art algorithms for ERP classification. Online experiments were additionally implemented for the validation. The superior classification performance in using few training samples shows that the STDA is effective to reduce the system calibration time and improve the classification accuracy, thereby enhancing the practicability of ERP-based BCI.

Choosing Open Source ERP Systems: What Reasons Are There For Doing So?

NASA Astrophysics Data System (ADS)

Johansson, Björn; Sudzina, Frantisek

Enterprise resource planning (ERP) systems attract a high attention and open source software does it as well. The question is then if, and if so, when do open source ERP systems take off. The paper describes the status of open source ERP systems. Based on literature review of ERP system selection criteria based on Web of Science articles, it discusses reported reasons for choosing open source or proprietary ERP systems. Last but not least, the article presents some conclusions that could act as input for future research. The paper aims at building up a foundation for the basic question: What are the reasons for an organization to adopt open source ERP systems.

Introduction of an Emergency Response Plan for flood loading of Sultan Abu Bakar Dam in Malaysia

NASA Astrophysics Data System (ADS)

Said, N. F. Md; Sidek, L. M.; Basri, H.; Muda, R. S.; Razad, A. Z. Abdul

2016-03-01

Sultan Abu Bakar Dam Emergency Response Plan (ERP) is designed to assist employees for identifying, monitoring, responding and mitigation dam safety emergencies. This paper is outlined to identification of an organization chart, responsibility for emergency management team and triggering level in Sultan Abu Bakar Dam ERP. ERP is a plan that guides responsibilities for proper operation of Sultan Abu Bakar Dam in respond to emergency incidents affecting the dam. Based on this study four major responsibilities are needed for Abu Bakar Dam owing to protect any probable risk for downstream which they can be Incident Commander, Deputy Incident Commander, On-Scene Commander, Civil Engineer. In conclusion, having organization charts based on ERP studies can be helpful for decreasing the probable risks in any projects such as Abu Bakar Dam and it is a way to identify and suspected and actual dam safety emergencies.

Attention effects on the processing of task-relevant and task-irrelevant speech sounds and letters

PubMed Central

Mittag, Maria; Inauri, Karina; Huovilainen, Tatu; Leminen, Miika; Salo, Emma; Rinne, Teemu; Kujala, Teija; Alho, Kimmo

2013-01-01

We used event-related brain potentials (ERPs) to study effects of selective attention on the processing of attended and unattended spoken syllables and letters. Participants were presented with syllables randomly occurring in the left or right ear and spoken by different voices and with a concurrent foveal stream of consonant letters written in darker or lighter fonts. During auditory phonological (AP) and non-phonological tasks, they responded to syllables in a designated ear starting with a vowel and spoken by female voices, respectively. These syllables occurred infrequently among standard syllables starting with a consonant and spoken by male voices. During visual phonological and non-phonological tasks, they responded to consonant letters with names starting with a vowel and to letters written in dark fonts, respectively. These letters occurred infrequently among standard letters with names starting with a consonant and written in light fonts. To examine genuine effects of attention and task on ERPs not overlapped by ERPs associated with target processing or deviance detection, these effects were studied only in ERPs to auditory and visual standards. During selective listening to syllables in a designated ear, ERPs to the attended syllables were negatively displaced during both phonological and non-phonological auditory tasks. Selective attention to letters elicited an early negative displacement and a subsequent positive displacement (Pd) of ERPs to attended letters being larger during the visual phonological than non-phonological task suggesting a higher demand for attention during the visual phonological task. Active suppression of unattended speech during the AP and non-phonological tasks and during the visual phonological tasks was suggested by a rejection positivity (RP) to unattended syllables. We also found evidence for suppression of the processing of task-irrelevant visual stimuli in visual ERPs during auditory tasks involving left-ear syllables. PMID:24348324

Limited role of phonology in reading Chinese two-character compounds: evidence from an ERP study.

PubMed

Wong, A W-K; Wu, Y; Chen, H-C

2014-01-03

This study investigates the role of phonology in reading logographic Chinese. Specifically, whether phonological information is obligatorily activated in reading Chinese two-character compounds was examined using the masked-priming paradigm with event-related potential (ERP) recordings. Twenty-two native Cantonese Chinese speakers participated in a lexical decision experiment. The targets were visually presented Chinese two-character strings and the participants were asked to judge whether the target in each trial was a legitimate compound word in Chinese. Each target was preceded by a briefly presented word prime. The prime and target shared an identical constituent character in the Character-related condition, a syllable in the Syllable-related condition, were semantically related in the Semantic-related condition, and were unrelated (both phonologically and semantically) in the control condition. The prime–target relationship was manipulated to probe the effects of word-form (i.e., character- or syllable-relatedness) and word-semantic relatedness on phonological (as indexed by an N250 ERP component) and semantic (as indexed by an N400 ERP component) processing. Significant and comparable facilitation effects in reaction time, relative to the control, were observed in the Character-related and the Semantic-related conditions. Furthermore, a significant reduction in ERP amplitudes (N250), relative to the control, was obtained in the Character-related condition in the time window of 150-250 ms post target. In addition, attenuation in ERP amplitudes was found in the Semantic-related condition in the window of 250-500 ms (N400). However, no significant results (neither behavioral nor ERP) were found in the Syllable-related condition. These results suggest that phonological activation is not mandatory and the role of phonology is minimal at best in reading Chinese two-character compounds.

Picture Superiority Doubly Dissociates the ERP Correlates of Recollection and Familiarity

ERIC Educational Resources Information Center

Curran, Tim; Doyle, Jeanne

2011-01-01

Two experiments investigated the processes underlying the picture superiority effect on recognition memory. Studied pictures were associated with higher accuracy than studied words, regardless of whether test stimuli were words (Experiment 1) or pictures (Experiment 2). Event-related brain potentials (ERPs) recorded during test suggested that the…

ERP Study of Pre-Attentive Auditory Processing in Treatment-Refractory Schizophrenia

ERIC Educational Resources Information Center

Milovan, Denise L.; Baribeau, Jacinthe; Roth, Robert M.; Stip, Emmanuel

2004-01-01

Event-related potential (ERP) studies have demonstrated impaired auditory sensory processing in patients with schizophrenia, as reflected in abnormal mismatch negativity (MMN). We sought to extend this finding by evaluating MMN in 13 treatment-refractory patients with schizophrenia, and 14 age- and gender-matched healthy controls. Subjects…

Attentional Bias in Anxiety: A Behavioral and ERP Study

ERIC Educational Resources Information Center

Bar-Haim, Yair; Lamy, Dominique; Glickman, Shlomit

2005-01-01

Accumulating evidence suggests the existence of a processing bias in favor of threat-related stimulation in anxious individuals. Using behavioral and ERP measures, the present study investigated the deployment of attention to face stimuli with different emotion expressions in high-anxious and low-anxious participants. An attention-shifting…

Brain Oscillations in Sport: Toward EEG Biomarkers of Performance.

PubMed

Cheron, Guy; Petit, Géraldine; Cheron, Julian; Leroy, Axelle; Cebolla, Anita; Cevallos, Carlos; Petieau, Mathieu; Hoellinger, Thomas; Zarka, David; Clarinval, Anne-Marie; Dan, Bernard

2016-01-01

Brain dynamics is at the basis of top performance accomplishment in sports. The search for neural biomarkers of performance remains a challenge in movement science and sport psychology. The non-invasive nature of high-density electroencephalography (EEG) recording has made it a most promising avenue for providing quantitative feedback to practitioners and coaches. Here, we review the current relevance of the main types of EEG oscillations in order to trace a perspective for future practical applications of EEG and event-related potentials (ERP) in sport. In this context, the hypotheses of unified brain rhythms and continuity between wake and sleep states should provide a functional template for EEG biomarkers in sport. The oscillations in the thalamo-cortical and hippocampal circuitry including the physiology of the place cells and the grid cells provide a frame of reference for the analysis of delta, theta, beta, alpha (incl.mu), and gamma oscillations recorded in the space field of human performance. Based on recent neuronal models facilitating the distinction between the different dynamic regimes (selective gating and binding) in these different oscillations we suggest an integrated approach articulating together the classical biomechanical factors (3D movements and EMG) and the high-density EEG and ERP signals to allow finer mathematical analysis to optimize sport performance, such as microstates, coherency/directionality analysis and neural generators.

Brain Oscillations in Sport: Toward EEG Biomarkers of Performance

PubMed Central

Cheron, Guy; Petit, Géraldine; Cheron, Julian; Leroy, Axelle; Cebolla, Anita; Cevallos, Carlos; Petieau, Mathieu; Hoellinger, Thomas; Zarka, David; Clarinval, Anne-Marie; Dan, Bernard

2016-01-01

Brain dynamics is at the basis of top performance accomplishment in sports. The search for neural biomarkers of performance remains a challenge in movement science and sport psychology. The non-invasive nature of high-density electroencephalography (EEG) recording has made it a most promising avenue for providing quantitative feedback to practitioners and coaches. Here, we review the current relevance of the main types of EEG oscillations in order to trace a perspective for future practical applications of EEG and event-related potentials (ERP) in sport. In this context, the hypotheses of unified brain rhythms and continuity between wake and sleep states should provide a functional template for EEG biomarkers in sport. The oscillations in the thalamo-cortical and hippocampal circuitry including the physiology of the place cells and the grid cells provide a frame of reference for the analysis of delta, theta, beta, alpha (incl.mu), and gamma oscillations recorded in the space field of human performance. Based on recent neuronal models facilitating the distinction between the different dynamic regimes (selective gating and binding) in these different oscillations we suggest an integrated approach articulating together the classical biomechanical factors (3D movements and EMG) and the high-density EEG and ERP signals to allow finer mathematical analysis to optimize sport performance, such as microstates, coherency/directionality analysis and neural generators. PMID:26955362

Relationship between neural response and adaptation selectivity to form and color: an ERP study.

PubMed

Rentzeperis, Ilias; Nikolaev, Andrey R; Kiper, Daniel C; van Leeuwen, Cees

2012-01-01

Adaptation is widely used as a tool for studying selectivity to visual features. In these studies it is usually assumed that the loci of feature selective neural responses and adaptation coincide. We used an adaptation paradigm to investigate the relationship between response and adaptation selectivity in event-related potentials (ERPs). ERPs were evoked by the presentation of colored Glass patterns in a form discrimination task. Response selectivities to form and, to some extent, color of the patterns were reflected in the C1 and N1 ERP components. Adaptation selectivity to color was reflected in N1 and was followed by a late (300-500 ms after stimulus onset) effect of form adaptation. Thus for form, response and adaptation selectivity were manifested in non-overlapping intervals. These results indicate that adaptation and response selectivity can be associated with different processes. Therefore, inferring selectivity from an adaptation paradigm requires analysis of both adaptation and neural response data.

Performance improvement of ERP-based brain-computer interface via varied geometric patterns.

PubMed

Ma, Zheng; Qiu, Tianshuang

2017-12-01

Recently, many studies have been focusing on optimizing the stimulus of an event-related potential (ERP)-based brain-computer interface (BCI). However, little is known about the effectiveness when increasing the stimulus unpredictability. We investigated a new stimulus type of varied geometric pattern where both complexity and unpredictability of the stimulus are increased. The proposed and classical paradigms were compared in within-subject experiments with 16 healthy participants. Results showed that the BCI performance was significantly improved for the proposed paradigm, with an average online written symbol rate increasing by 138% comparing with that of the classical paradigm. Amplitudes of primary ERP components, such as N1, P2a, P2b, N2, were also found to be significantly enhanced with the proposed paradigm. In this paper, a novel ERP BCI paradigm with a new stimulus type of varied geometric pattern is proposed. By jointly increasing the complexity and unpredictability of the stimulus, the performance of an ERP BCI could be considerably improved.

Analysis of the interaction of calcitriol with the disulfide isomerase ERp57

NASA Astrophysics Data System (ADS)

Gaucci, Elisa; Raimondo, Domenico; Grillo, Caterina; Cervoni, Laura; Altieri, Fabio; Nittari, Giulio; Eufemi, Margherita; Chichiarelli, Silvia

2016-11-01

Calcitriol, the active form of vitamin D3, can regulate the gene expression through the binding to the nuclear receptor VDR, but it can also display nongenomic actions, acting through a membrane-associated receptor, which has been discovered as the disulfide isomerase ERp57. The aim of our research is to identify the binding sites for calcitriol in ERp57 and to analyze their interaction. We first studied the interaction through bioinformatics and fluorimetric analyses. Subsequently, we focused on two protein mutants containing the predicted interaction domains with calcitriol: abb’-ERp57, containing the first three domains, and a’-ERp57, the fourth domain only. To consolidate the achievements we used the calorimetric approach to the whole protein and its mutants. Our results allow us to hypothesize that the interaction with the a’ domain contributes to a greater extent than the other potential binding sites to the dissociation constant, calculated as a Kd of about 10-9 M.

Design Patterns Application in the ERP Systems Improvements

NASA Astrophysics Data System (ADS)

Jovičić, Bojan; Vlajić, Siniša

Design patterns application have long been present in software engineering. The same is true for ERP systems in business software. Is it possible that ERP systems do not have a good maintenance score? We have found out that there is room for maintenance improvement and that it is possible to improve ERP systems using design patterns. We have conducted comparative analysis of ease of maintenance of the ERP systems. The results show that the average score for our questions is 64%, with most answers for ERP systems like SAP, Oracle EBS, Dynamics AX. We found that 59% of ERP system developer users are not familiar with design patterns. Based on this research, we have chosen Dynamics AX as the ERP system for examination of design patterns improvement possibilities. We used software metrics to measure improvement possibility. We found that we could increase the Conditional Complexity score 17-fold by introducing design patterns.

ERP Go/NoGo condition effects are better detected with separate PCAs.

PubMed

Barry, Robert J; De Blasio, Frances M; Fogarty, Jack S; Karamacoska, Diana

2016-08-01

We explored the separation of Go and NoGo effects in the ERP components elicited in an equiprobable Go/NoGo task, using different forms of temporal Principal Components Analysis (PCA). Following exploratory simulation studies assessing the PCA impact of latency jitter and between-condition latency differences in the P3 latency range, an empirical study compared results of a Combined PCA carried out using both Go and NoGo ERPs together as input, with those from two Separate PCAs carried out on the Go and NoGo ERPs separately. The simulation studies indicated that Separate PCAs provide adequate component recovery in the presence of P3 latency jitter, and that Combined PCAs provide good separation of components only when systematic condition-related latency differences are sufficiently large (here ~110ms). In the empirical data, broadly-similar components were obtained from the Combined and Separate PCAs, supporting previous findings from Combined PCA investigations, and the consequent interpretations of the sequential processing involved. However, the Separate PCAs generated latency differences for components in the Go and NoGo processing chains that better matched the late Go/NoGo ERP peaks, and produced better-defined and larger components that fitted the stages in a hypothetical processing schema developed for this paradigm. Overall, the Separate PCAs yielded a better partitioning of the ERP variance associated with the Go and NoGo conditions, and should be considered as the first choice in future investigations if systematic component or subcomponent latency differences are present or suspected. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantifying the Time Course of Visual Object Processing Using ERPs: It's Time to Up the Game

PubMed Central

Rousselet, Guillaume A.; Pernet, Cyril R.

2011-01-01

Hundreds of studies have investigated the early ERPs to faces and objects using scalp and intracranial recordings. The vast majority of these studies have used uncontrolled stimuli, inappropriate designs, peak measurements, poor figures, and poor inferential and descriptive group statistics. These problems, together with a tendency to discuss any effect p < 0.05 rather than to report effect sizes, have led to a research field very much qualitative in nature, despite its quantitative inspirations, and in which predictions do not go beyond condition A > condition B. Here we describe the main limitations of face and object ERP research and suggest alternative strategies to move forward. The problems plague intracranial and surface ERP studies, but also studies using more advanced techniques – e.g., source space analyses and measurements of network dynamics, as well as many behavioral, fMRI, TMS, and LFP studies. In essence, it is time to stop amassing binary results and start using single-trial analyses to build models of visual perception. PMID:21779262

Face repetition detection and social interest: An ERP study in adults with and without Williams syndrome.

PubMed

Key, Alexandra P; Dykens, Elisabeth M

2016-12-01

The present study examined possible neural mechanisms underlying increased social interest in persons with Williams syndrome (WS). Visual event-related potentials (ERPs) during passive viewing were used to compare incidental memory traces for repeated vs. single presentations of previously unfamiliar social (faces) and nonsocial (houses) images in 26 adults with WS and 26 typical adults. Results indicated that participants with WS developed familiarity with the repeated faces and houses (frontal N400 response), but only typical adults evidenced the parietal old/new effect (previously associated with stimulus recollection) for the repeated faces. There was also no evidence of exceptional salience of social information in WS, as ERP markers of memory for repeated faces vs. houses were not significantly different. Thus, while persons with WS exhibit behavioral evidence of increased social interest, their processing of social information in the absence of specific instructions may be relatively superficial. The ERP evidence of face repetition detection in WS was independent of IQ and the earlier perceptual differentiation of social vs. nonsocial stimuli. Large individual differences in ERPs of participants with WS may provide valuable information for understanding the WS phenotype and have relevance for educational and treatment purposes.

Implicit and explicit categorization of natural scenes.

PubMed

Codispoti, Maurizio; Ferrari, Vera; De Cesarei, Andrea; Cardinale, Rossella

2006-01-01

Event-related potential (ERP) studies have consistently found that emotionally arousing (pleasant and unpleasant) pictures elicit a larger late positive potential (LPP) than neutral pictures in a window from 400 to 800 ms after picture onset. In addition, an early ERP component has been reported to vary with emotional arousal in a window from about 150 to 300 ms with affective, compared to neutral stimuli, prompting significantly less positivity over occipito-temporal sites. Similar early and late ERP components have been found in explicit categorization tasks, suggesting that selective attention to target features results in similar cortical changes. Several studies have shown that the affective modulation of the LPP persisted even when the same pictures are repeated several times, when they are presented as distractors, or when participants are engaged in a competing task. These results indicate that categorization of affective stimuli is an obligatory process. On the other hand, perceptual factors (e.g., stimulus size) seem to affect the early ERP component but not the affective modulation of the LPP. Although early and late ERP components vary with stimulus relevance, given that they are differentially affected by stimulus and task manipulations, they appear to index different facets of picture processing.

Color and context: an ERP study on intrinsic and extrinsic feature binding in episodic memory.

PubMed

Ecker, Ullrich K H; Zimmer, Hubert D; Groh-Bordin, Christian

2007-09-01

Episodic memory for intrinsic item and extrinsic context information is postulated to rely on two distinct types of representation: object and episodic tokens. These provide the basis for familiarity and recollection, respectively. Electrophysiological indices of these processes (ERP old-new effects) were used together with behavioral data to test these assumptions. We manipulated an intrinsic object feature (color; Experiment 1) and a contextual feature (background; Experiments 1 and 2). In an inclusion task (Experiment 1), the study-test manipulation of color affected object recognition performance and modulated ERP old-new effects associated with both familiarity and recollection. In contrast, a contextual manipulation had no effect, although both intrinsic and extrinsic information was available in a direct feature (source memory) test. When made task relevant (exclusion task; Experiment 2), however, context affected the ERP recollection effect, while still leaving the ERP familiarity effect uninfluenced. We conclude that intrinsic features bound in object tokens are involuntarily processed during object recognition, thus influencing familiarity, whereas context features bound in episodic tokens are voluntarily accessed, exclusively influencing recollection. Figures depicting all the electrodes analyzed are available in an online supplement at www.psychonomic.org/archive.

47 CFR 74.796 - Modification of digital transmission systems and analog transmission systems for digital operation.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Subtract the value determined in the previous step from the authorized effective radiated power (“ERP”) of... ERP must be expressed in decibels above one kilowatt: ERP(dBk) = 10 log ERP(kW); (4) Convert the ERP calculated in the previous step to units of kilowatts; and (5) The ERP value determined through the above...

Analysis of independent components of cognitive event related potentials in a group of ADHD adults.

PubMed

Markovska-Simoska, Silvana; Pop-Jordanova, Nada; Pop-Jordanov, Jordan

In the last decade, many studies have tried to define the neural correlates of attention deficit hyperactivity disorder (ADHD). The main aim of this study is the comparison of the ERPs independent components in the four QEEG subtypes in a group of ADHD adults as a basis for defining the corresponding endophenotypes among ADHD population. Sixty-seven adults diagnosed as ADHD according to the DSM-IV criteria and 50 age-matched control subjects participated in the study. The brain activity of the subjects was recorded by 19 channel quantitative electroencephalography (QEEG) system in two neuropsychological tasks (visual and emotional continuous performance tests). The ICA method was applied for separation of the independent ERPs components. The components were associated with distinct psychological operations, such as engagement operations (P3bP component), comparison (vcomTL and vcom TR), motor inhibition (P3supF) and monitoring (P4monCC) operations. The ERPs results point out that there is disturbance in executive functioning in investigated ADHD group obtained by the significantly lower amplitude and longer latency for the engagement (P3bP), motor inhibition (P3supF) and monitoring (P4monCC) components. Particularly, the QEEG subtype IV was with the most significant ERPs differences comparing to the other subtypes. In particular, the most prominent difference in the ERPs independent components for the QEEG subtype IV in comparison to other three subtypes, rise many questions and becomes the subject for future research. This study aims to advance and facilitate the use of neurophysiological procedures (QEEG and ERPs) in clinical practice as objective measures of ADHD for better assessment, subtyping and treatment of ADHD.

Effects of Type of Agreement Violation and Utterance Position on the Auditory Processing of Subject-Verb Agreement: An ERP Study

PubMed Central

Dube, Sithembinkosi; Kung, Carmen; Peter, Varghese; Brock, Jon; Demuth, Katherine

2016-01-01

Previous ERP studies have often reported two ERP components—LAN and P600—in response to subject-verb (S-V) agreement violations (e.g., the boys *runs). However, the latency, amplitude and scalp distribution of these components have been shown to vary depending on various experiment-related factors. One factor that has not received attention is the extent to which the relative perceptual salience related to either the utterance position (verbal inflection in utterance-medial vs. utterance-final contexts) or the type of agreement violation (errors of omission vs. errors of commission) may influence the auditory processing of S-V agreement. The lack of reports on these effects in ERP studies may be due to the fact that most studies have used the visual modality, which does not reveal acoustic information. To address this gap, we used ERPs to measure the brain activity of Australian English-speaking adults while they listened to sentences in which the S-V agreement differed by type of agreement violation and utterance position. We observed early negative and positive clusters (AN/P600 effects) for the overall grammaticality effect. Further analysis revealed that the mean amplitude and distribution of the P600 effect was only significant in contexts where the S-V agreement violation occurred utterance-finally, regardless of type of agreement violation. The mean amplitude and distribution of the negativity did not differ significantly across types of agreement violation and utterance position. These findings suggest that the increased perceptual salience of the violation in utterance final position (due to phrase-final lengthening) influenced how S-V agreement violations were processed during sentence comprehension. Implications for the functional interpretation of language-related ERPs and experimental design are discussed. PMID:27625617

Effects of Type of Agreement Violation and Utterance Position on the Auditory Processing of Subject-Verb Agreement: An ERP Study.

PubMed

Dube, Sithembinkosi; Kung, Carmen; Peter, Varghese; Brock, Jon; Demuth, Katherine

2016-01-01

Previous ERP studies have often reported two ERP components-LAN and P600-in response to subject-verb (S-V) agreement violations (e.g., the boys (*) runs). However, the latency, amplitude and scalp distribution of these components have been shown to vary depending on various experiment-related factors. One factor that has not received attention is the extent to which the relative perceptual salience related to either the utterance position (verbal inflection in utterance-medial vs. utterance-final contexts) or the type of agreement violation (errors of omission vs. errors of commission) may influence the auditory processing of S-V agreement. The lack of reports on these effects in ERP studies may be due to the fact that most studies have used the visual modality, which does not reveal acoustic information. To address this gap, we used ERPs to measure the brain activity of Australian English-speaking adults while they listened to sentences in which the S-V agreement differed by type of agreement violation and utterance position. We observed early negative and positive clusters (AN/P600 effects) for the overall grammaticality effect. Further analysis revealed that the mean amplitude and distribution of the P600 effect was only significant in contexts where the S-V agreement violation occurred utterance-finally, regardless of type of agreement violation. The mean amplitude and distribution of the negativity did not differ significantly across types of agreement violation and utterance position. These findings suggest that the increased perceptual salience of the violation in utterance final position (due to phrase-final lengthening) influenced how S-V agreement violations were processed during sentence comprehension. Implications for the functional interpretation of language-related ERPs and experimental design are discussed.

Response-Related Potentials during Semantic Priming: The Effect of a Speeded Button Response Task on ERPs

PubMed Central

van Vliet, Marijn; Manyakov, Nikolay V.; Storms, Gert; Fias, Wim; Wiersema, Jan R.; Van Hulle, Marc M.

2014-01-01

This study examines the influence of a button response task on the event-related potential (ERP) in a semantic priming experiment. Of particular interest is the N400 component. In many semantic priming studies, subjects are asked to respond to a stimulus as fast and accurately as possible by pressing a button. Response time (RT) is recorded in parallel with an electroencephalogram (EEG) for ERP analysis. In this case, the response occurs in the time window used for ERP analysis and response-related components may overlap with stimulus-locked ones such as the N400. This has led to a recommendation against such a design, although the issue has not been explored in depth. Since studies keep being published that disregard this issue, a more detailed examination of influence of response-related potentials on the ERP is needed. Two experiments were performed in which subjects pressed one of two buttons with their dominant hand in response to word-pairs with varying association strength (AS), indicating a personal judgement of association between the two words. In the first experiment, subjects were instructed to respond as fast and accurately as possible. In the second experiment, subjects delayed their button response to enforce a one second interval between the onset of the target word and the button response. Results show that in the first experiment a P3 component and motor-related potentials (MRPs) overlap with the N400 component, which can cause a misinterpretation of the latter. In order to study the N400 component, the button response should be delayed to avoid contamination of the ERP with response-related components. PMID:24516556

Electrophysiological correlates of retrieval orientation in reality monitoring.

PubMed

Rosburg, Timm; Mecklinger, Axel; Johansson, Mikael

2011-02-14

Retrieval orientation describes the modulation in the processing of retrieval cues by the nature of the targeted material in memory. Retrieval orientation is usually investigated by analyzing the cortical responses to new (unstudied) material when different memory contents are targeted. This approach avoids confounding effects of retrieval success. We investigated the neural correlates of retrieval orientation in reality monitoring with event-related potentials (ERPs) and assessed the impact of retrieval accuracy on obtained ERP measures. Thirty-two subjects studied visually presented object names that were followed either by a picture of that object (perceived condition) or by the instruction to mentally generate such a picture (imagine condition). Subsequently, subjects had to identify object names of one study condition and reject object names of the second study condition together with newly presented object names. The data analysis showed that object names were more accurately identified when they had been presented in the perceived condition. Two topographically distinct ERP effects of retrieval orientation were revealed: From 600 to 1100 ms after stimulus representation, ERPs were more positive at frontal electrode sites when object names from the imagine condition were targeted. The analysis of response-locked ERP data revealed an additional effect at posterior electrode sites, with more negative ERPs shortly after response onset when items from the imagine condition were targeted. The ERP effect at frontal electrode sites, but not at posterior electrode sites was modulated by relative memory accuracy, with stronger effects in subjects who had lower memory accuracy for items of the imagine condition. The findings are suggestive for a contribution of frontal brain areas to retrieval orientation processes in reality monitoring and indicate that neural correlates of retrieval orientation can be modulated by retrieval effort, with stronger activation of these correlates with increasing task demands. Copyright © 2010 Elsevier Inc. All rights reserved.

An international multicenter study comparing EUS-guided pancreatic duct drainage with enteroscopy-assisted endoscopic retrograde pancreatography after Whipple surgery.

PubMed

Chen, Yen-I; Levy, Michael J; Moreels, Tom G; Hajijeva, Gulara; Will, Uwe; Artifon, Everson L; Hara, Kazuo; Kitano, Masayuki; Topazian, Mark; Abu Dayyeh, Barham; Reichel, Andreas; Vilela, Tiago; Ngamruengphong, Saowanee; Haito-Chavez, Yamile; Bukhari, Majidah; Okolo, Patrick; Kumbhari, Vivek; Ismail, Amr; Khashab, Mouen A

2017-01-01

Endoscopic management of post-Whipple pancreatic adverse events (AEs) with enteroscopy-assisted endoscopic retrograde pancreatography (e-ERP) is associated with high failure rates. EUS-guided pancreatic duct drainage (EUS-PDD) has shown promising results; however, no comparative data have been done for these 2 modalities. The goal of this study is to compare EUS-PDD with e-ERP in terms of technical success (PDD through dilation/stent), clinical success (improvement/resolution of pancreatic-type symptoms), and AE rates in patients with post-Whipple anatomy. This is an international multicenter comparative retrospective study at 7 tertiary centers (2 United States, 2 European, 2 Asian, and 1 South American). All consecutive patients who underwent EUS-PDD or e-ERP between January 2010 and August 2015 were included. In total, 66 patients (mean age, 57 years; 48% women) and 75 procedures were identified with 40 in EUS-PDD and 35 in e-ERP. Technical success was achieved in 92.5% of procedures in the EUS-PDD group compared with 20% of procedures in the e-ERP group (OR, 49.3; P < .001). Clinical success (per patient) was attained in 87.5% of procedures in the EUS-PDD group compared with 23.1% in the e-ERP group (OR, 23.3; P < .001). AEs occurred more commonly in the EUS-PDD group (35% vs 2.9%, P < .001). However, all AEs were rated as mild or moderate. Procedure time and length of stay were not significantly different between the 2 groups. EUS-PDD is superior to e-ERP in post-Whipple anatomy in terms of efficacy with acceptable safety. As such, EUS-PDD should be considered as a potential first-line treatment in post-pancreaticoduodenectomy anatomy when necessary expertise is available. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Improving Outcomes in Colorectal Surgery by Sequential Implementation of Multiple Standardized Care Programs.

PubMed

Keenan, Jeffrey E; Speicher, Paul J; Nussbaum, Daniel P; Adam, Mohamed Abdelgadir; Miller, Timothy E; Mantyh, Christopher R; Thacker, Julie K M

2015-08-01

The purpose of this study was to examine the impact of the sequential implementation of the enhanced recovery program (ERP) and surgical site infection bundle (SSIB) on short-term outcomes in colorectal surgery (CRS) to determine if the presence of multiple standardized care programs provides additive benefit. Institutional ACS-NSQIP data were used to identify patients who underwent elective CRS from September 2006 to March 2013. The cohort was stratified into 3 groups relative to implementation of the ERP (February 1, 2010) and SSIB (July 1, 2011). Unadjusted characteristics and 30-day outcomes were assessed, and inverse proportional weighting was then used to determine the adjusted effect of these programs. There were 787 patients included: 337, 165, and 285 in the pre-ERP/SSIB, post-ERP/pre-SSIB, and post-ERP/SSIB periods, respectively. After inverse probability weighting (IPW) adjustment, groups were balanced with respect to patient and procedural characteristics considered. Compared with the pre-ERP/SSIB group, the post-ERP/pre-SSIB group had significantly reduced length of hospitalization (8.3 vs 6.6 days, p = 0.01) but did not differ with respect to postoperative wound complications and sepsis. Subsequent introduction of the SSIB then resulted in a significant decrease in superficial SSI (16.1% vs 6.3%, p < 0.01) and postoperative sepsis (11.2% vs 1.8%, p < 0.01). Finally, inflation-adjusted mean hospital cost for a CRS admission fell from $31,926 in 2008 to $22,044 in 2013 (p < 0.01). Sequential implementation of the ERP and SSIB provided incremental improvements in CRS outcomes while controlling hospital costs, supporting their combined use as an effective strategy toward improving the quality of patient care. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Implementation of enhanced recovery programme for laparoscopic distal pancreatectomy: feasibility, safety and cost analysis.

PubMed

Richardson, John; Di Fabio, Francesco; Clarke, Hannah; Bajalan, Mohammed; Davids, Joe; Abu Hilal, Mohammed

2015-01-01

The adoption of laparoscopy for distal pancreatectomy has proven to substantially improve short-term outcomes. Stress response after major surgery can be further minimized within an enhanced recovery programme (ERP). However, data on the potential benefit of an ERP for laparoscopic distal pancreatectomy are still lacking. The aim was to assess the feasibility, safety and cost of ERP for patients undergoing laparoscopic distal pancreatectomy. This is a case-control study from a Tertiary University Hospital. Sixty-six consecutive patients who underwent laparoscopic distal pancreatectomy were analyzed. Twenty-two patients were enrolled for the ERP and compared with previous consecutive 44 patients managed traditionally (1:2 ratio). Operative details, post-operative outcome and cost analysis were compared in the two groups. Patients enrolled in the ERP had similar intraoperative blood loss (median 165 ml vs. 200 ml; p = 0.176), operation time (225 min vs. 210 min; p = 0.633), time to remove naso-gastric tube (1 vs. 1 day; p = 0.081) but significantly shorter time to mobilization (median 1 vs. 2 days; p = 0.0001), start solid diet (2 vs. 3 days; p = 0004), and pass stools (3 vs. 5 days; p = 0.002) compared to the control group. Median length of stay was significantly shorter in the ERP group (3 vs. 6 days; p < 0.0001). No significant difference in readmission or complication rate was observed. Cost analysis was significantly in favor of the ERP group (p = 0.0004). Implementation of ERP optimizes outcomes for laparoscopic distal pancreatectomy with significant earlier return to normal gut function, reduced length of stay and cost saving. Copyright © 2015 IAP and EPC. Published by Elsevier B.V. All rights reserved.

A-Type Carrier Protein ErpA Is Essential for Formation of an Active Formate-Nitrate Respiratory Pathway in Escherichia coli K-12

PubMed Central

Pinske, Constanze

2012-01-01

A-type carrier (ATC) proteins of the Isc (iron-sulfur cluster) and Suf (sulfur mobilization) iron-sulfur ([Fe-S]) cluster biogenesis pathways are proposed to traffic preformed [Fe-S] clusters to apoprotein targets. In this study, we analyzed the roles of the ATC proteins ErpA, IscA, and SufA in the maturation of the nitrate-inducible, multisubunit anaerobic respiratory enzymes formate dehydrogenase N (Fdh-N) and nitrate reductase (Nar). Mutants lacking SufA had enhanced activities of both enzymes. While both Fdh-N and Nar activities were strongly reduced in an iscA mutant, both enzymes were inactive in an erpA mutant and in a mutant unable to synthesize the [Fe-S] cluster scaffold protein IscU. It could be shown for both Fdh-N and Nar that loss of enzyme activity correlated with absence of the [Fe-S] cluster-containing small subunit. Moreover, a slowly migrating form of the catalytic subunit FdnG of Fdh-N was observed, consistent with impeded twin arginine translocation (TAT)-dependent transport. The highly related Fdh-O enzyme was also inactive in the erpA mutant. Although the Nar enzyme has its catalytic subunit NarG localized in the cytoplasm, it also exhibited aberrant migration in an erpA iscA mutant, suggesting that these modular enzymes lack catalytic integrity due to impaired cofactor biosynthesis. Cross-complementation experiments demonstrated that multicopy IscA could partially compensate for lack of ErpA with respect to Fdh-N activity but not Nar activity. These findings suggest that ErpA and IscA have overlapping roles in assembly of these anaerobic respiratory enzymes but demonstrate that ErpA is essential for the production of active enzymes. PMID:22081393

[The P300 based brain-computer interface: effect of stimulus position in a stimulus train].

PubMed

Ganin, I P; Shishkin, S L; Kochetova, A G; Kaplan, A Ia

2012-01-01

The P300 brain-computer interface (BCI) is currently the most efficient BCI. This interface is based on detection of the P300 wave of the brain potentials evoked when a symbol related to the intended input is highlighted. To increase operation speed of the P300 BCI, reduction of the number of stimuli repetitions is needed. This reduction leads to increase of the relative contribution to the input symbol detection from the reaction to the first target stimulus. It is known that the event-related potentials (ERP) to the first stimulus presentations can be different from the ERP to stimuli presented latter. In particular, the amplitude of responses to the first stimulus presentations is often increased, which is beneficial for their recognition by the BCI. However, this effect was not studied within the BCI framework. The current study examined the ERP obtained from healthy participants (n = 14) in the standard P300 BCI paradigm using 10 trials, as well as in the modified P300 BCI with stimuli presented on moving objects in triple-trial (n = 6) and single-trial (n = 6) stimulation modes. Increased ERP amplitude was observed in response to the first target stimuli in both conditions, as well as in the single-trial mode comparing to triple-trial. We discuss the prospects of using the specific features of the ERP to first stimuli and the single-trial ERP for optimizing the high-speed modes in the P300 BCIs.

Competitive advantage in the ERP system's value-chain and its influence on future development

NASA Astrophysics Data System (ADS)

Johansson, Björn; Newman, Mike

2010-02-01

Using the resource-based view, we present a set of propositions related to enterprise resource planning (ERP) development, reflections on competitive advantage and the different roles that stakeholders play in the value-chain. This has the goal of building a foundation for future research on ERPs and how stakeholders' desire to achieve competitive advantage influence ERP development, especially when it comes to development of a more standardised or pre-customised ERP system. The propositions also act as a foundation for increasing our knowledge concerning the difficulty in developing improved ERP systems.

The effect of encoding manipulation on word-stem cued recall: an event-related potential study.

PubMed

Fay, Séverine; Isingrini, Michel; Ragot, Richard; Pouthas, Viviane

2005-08-01

The purpose of the present study was to find out whether the neural correlates of explicit retrieval from episodic memory would vary according to conditions at encoding when the words were presented in separate study/test blocks. Event-related potentials (ERPs) were recorded while participants performed a word-stem cued-recall task. Deeply (semantically) studied words were associated with higher levels of recall and faster response times than shallowly (lexically) studied words. Robust ERP old/new effects were observed for each encoding condition. They varied in magnitude, being largest in the semantic condition. As expected, scalp distributions also differed: for deeply studied words, the old/new effect resembled that found in previous ERP studies of word-stem cued-recall tasks (parietal and right frontal effects, between 400-800 and 800-1100 ms post-stimulus), whereas for shallowly studied words, the parietal old/new effect was absent in the latter latency window. These results can be interpreted as reflecting access to different kinds of memory representation depending on the nature of the processing engaged during encoding. Furthermore, differences in the ERPs elicited by new items indicate that subjects adopted different processing strategies in the test blocks following each encoding condition.

Validation of the Emotiv EPOC EEG system for research quality auditory event-related potentials in children

PubMed Central

Preece, Kathryn A.; de Wit, Bianca; Glenn, Katharine; Fieder, Nora; Thie, Johnson; McArthur, Genevieve

2015-01-01

Background. Previous work has demonstrated that a commercial gaming electroencephalography (EEG) system, Emotiv EPOC, can be adjusted to provide valid auditory event-related potentials (ERPs) in adults that are comparable to ERPs recorded by a research-grade EEG system, Neuroscan. The aim of the current study was to determine if the same was true for children. Method. An adapted Emotiv EPOC system and Neuroscan system were used to make simultaneous EEG recordings in nineteen 6- to 12-year-old children under “passive” and “active” listening conditions. In the passive condition, children were instructed to watch a silent DVD and ignore 566 standard (1,000 Hz) and 100 deviant (1,200 Hz) tones. In the active condition, they listened to the same stimuli, and were asked to count the number of ‘high’ (i.e., deviant) tones. Results. Intraclass correlations (ICCs) indicated that the ERP morphology recorded with the two systems was very similar for the P1, N1, P2, N2, and P3 ERP peaks (r = .82 to .95) in both passive and active conditions, and less so, though still strong, for mismatch negativity ERP component (MMN; r = .67 to .74). There were few differences between peak amplitude and latency estimates for the two systems. Conclusions. An adapted EPOC EEG system can be used to index children’s late auditory ERP peaks (i.e., P1, N1, P2, N2, P3) and their MMN ERP component. PMID:25922794

Validation of the Emotiv EPOC EEG system for research quality auditory event-related potentials in children.

PubMed

Badcock, Nicholas A; Preece, Kathryn A; de Wit, Bianca; Glenn, Katharine; Fieder, Nora; Thie, Johnson; McArthur, Genevieve

2015-01-01

Background. Previous work has demonstrated that a commercial gaming electroencephalography (EEG) system, Emotiv EPOC, can be adjusted to provide valid auditory event-related potentials (ERPs) in adults that are comparable to ERPs recorded by a research-grade EEG system, Neuroscan. The aim of the current study was to determine if the same was true for children. Method. An adapted Emotiv EPOC system and Neuroscan system were used to make simultaneous EEG recordings in nineteen 6- to 12-year-old children under "passive" and "active" listening conditions. In the passive condition, children were instructed to watch a silent DVD and ignore 566 standard (1,000 Hz) and 100 deviant (1,200 Hz) tones. In the active condition, they listened to the same stimuli, and were asked to count the number of 'high' (i.e., deviant) tones. Results. Intraclass correlations (ICCs) indicated that the ERP morphology recorded with the two systems was very similar for the P1, N1, P2, N2, and P3 ERP peaks (r = .82 to .95) in both passive and active conditions, and less so, though still strong, for mismatch negativity ERP component (MMN; r = .67 to .74). There were few differences between peak amplitude and latency estimates for the two systems. Conclusions. An adapted EPOC EEG system can be used to index children's late auditory ERP peaks (i.e., P1, N1, P2, N2, P3) and their MMN ERP component.

Linking customisation of ERP systems to support effort: an empirical study

NASA Astrophysics Data System (ADS)

Koch, Stefan; Mitteregger, Kurt

2016-01-01

The amount of customisation to an enterprise resource planning (ERP) system has always been a major concern in the context of the implementation. This article focuses on the phase of maintenance and presents an empirical study about the relationship between the amount of customising and the resulting support effort. We establish a structural equation modelling model that explains support effort using customisation effort, organisational characteristics and scope of implementation. The findings using data from an ERP provider show that there is a statistically significant effect: with an increasing amount of customisation, the quantity of telephone calls to support increases, as well as the duration of each call.

Spatiotemporal dynamics during processing of abstract and concrete verbs: an ERP study.

PubMed

Dalla Volta, Riccardo; Fabbri-Destro, Maddalena; Gentilucci, Maurizio; Avanzini, Pietro

2014-08-01

Different accounts have been proposed to explain the nature of concept representations. Embodied accounts claim a key involvement of sensory-motor systems during semantic processing while more traditional accounts posit that concepts are abstract mental entities independent of perceptual and motor brain systems. While the involvement of sensory-motor areas in concrete language processing is supported by a large number of studies, this involvement is far from being established when considering abstract language. The present study addressed abstract and concrete verb processing, by investigating the spatiotemporal dynamics of evoked responses by means of high density EEG while participants performed a semantic decision task. In addition, RTs to the same set of stimuli were collected. In both early and late time intervals, ERP scalp topography significantly differed according to word categories. Concrete verbs showed involvement of parieto-frontal networks for action, according to the implied body effector. In contrast, abstract verbs recruited mostly frontal regions outside the motor system, suggesting a non-motor semantic processing for this category. In addition, differently from what has been reported during action observation, the parietal recruitment related to concrete verbs presentation followed the frontal one. The present findings suggest that action word semantic is grounded in sensory-motor systems, provided a bodily effector is specified, while abstract concepts׳ representation cannot be easily explained by a motor embodiment. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Early infant diet and ERP Correlates of Speech Stimuli Discrimination in 9 month old infants

USDA-ARS?s Scientific Manuscript database

Processing and discrimination of speech stimuli were examined during the initial period of weaning in infants enrolled in a longitudinal study of infant diet and development (the Beginnings Study). Event-related potential measures (ERP; 128 sites) were used to compare the processing of speech stimul...

The Influence of Mathematical Ability and Morning Nutrition on Mental Arithmetic in Preadolescents: An ERP study.

USDA-ARS?s Scientific Manuscript database

The effects of eating or skipping breakfast on ERP correlates of mental arithmetic were studied in preadolescents differing in experience (age) and mathematical skills. Participants, randomly assigned to treatment [eat (B) or skip (SB) breakfast (each, n = 41)], were sub-grouped by age [8.8 yrs (B: ...

Semantic Integration Processes at Different Levels of Syntactic Hierarchy during Sentence Comprehension: An ERP Study

ERIC Educational Resources Information Center

Zhou, Xiaolin; Jiang, Xiaoming; Ye, Zheng; Zhang, Yaxu; Lou, Kaiyang; Zhan, Weidong

2010-01-01

An event-related potential (ERP) study was conducted to investigate the temporal neural dynamics of semantic integration processes at different levels of syntactic hierarchy during Chinese sentence reading. In a hierarchical structure, "subject noun" + "verb" + "numeral" + "classifier" + "object noun," the object noun is constrained by selectional…

Brain Potentials for Derivational Morphology: An ERP Study of Deadjectival Nominalizations in Spanish

ERIC Educational Resources Information Center

Havas, Viktoria; Rodriguez-Fornells, Antoni; Clahsen, Harald

2012-01-01

This study investigates brain potentials to derived word forms in Spanish. Two experiments were performed on derived nominals that differ in terms of their productivity and semantic properties but are otherwise similar, an acceptability judgment task and a reading experiment using event-related brain potentials (ERPs) in which correctly and…

Sentence Integration Processes: An ERP Study of Chinese Sentence Comprehension with Relative Clauses

ERIC Educational Resources Information Center

Yang, Chin Lung; Perfetti, Charles A.; Liu, Ying

2010-01-01

In an event-related potentials (ERPs) study, we examined the comprehension of different types of Chinese (Mandarin) relative clauses (object vs. subject-extracted) to test the universality and language specificity of sentence comprehension processes. Because Chinese lacks morphosyntactic cues to sentence constituent relations, it allows a test of…

Unaccusativity and Neurocognitive Indices of Second Language Acquisition: An ERP Study

ERIC Educational Resources Information Center

Purdy, John David

2010-01-01

Increased second-language (L2) proficiency is associated with a shift from explicit to implicit processing; however, the neural underpinnings are of this shift are not well understood. Furthermore, it is known that unaccusative verbs cause persistent difficulties in L2 learning. In this study, behavioral and event-related potential (ERP) responses…

Conceptual framework for the mapping of management process with information technology in a business process.

PubMed

Rajarathinam, Vetrickarthick; Chellappa, Swarnalatha; Nagarajan, Asha

2015-01-01

This study on component framework reveals the importance of management process and technology mapping in a business environment. We defined ERP as a software tool, which has to provide business solution but not necessarily an integration of all the departments. Any business process can be classified as management process, operational process and the supportive process. We have gone through entire management process and were enable to bring influencing components to be mapped with a technology for a business solution. Governance, strategic management, and decision making are thoroughly discussed and the need of mapping these components with the ERP is clearly explained. Also we suggest that implementation of this framework might reduce the ERP failures and especially the ERP misfit was completely rectified.

Conceptual Framework for the Mapping of Management Process with Information Technology in a Business Process

PubMed Central

Chellappa, Swarnalatha; Nagarajan, Asha

2015-01-01

This study on component framework reveals the importance of management process and technology mapping in a business environment. We defined ERP as a software tool, which has to provide business solution but not necessarily an integration of all the departments. Any business process can be classified as management process, operational process and the supportive process. We have gone through entire management process and were enable to bring influencing components to be mapped with a technology for a business solution. Governance, strategic management, and decision making are thoroughly discussed and the need of mapping these components with the ERP is clearly explained. Also we suggest that implementation of this framework might reduce the ERP failures and especially the ERP misfit was completely rectified. PMID:25861688

Articulation Artifacts During Overt Language Production in Event-Related Brain Potentials: Description and Correction.

PubMed

Ouyang, Guang; Sommer, Werner; Zhou, Changsong; Aristei, Sabrina; Pinkpank, Thomas; Abdel Rahman, Rasha

2016-11-01

Overt articulation produces strong artifacts in the electroencephalogram and in event-related potentials (ERPs), posing a serious problem for investigating language production with these variables. Here we describe the properties of articulation-related artifacts and propose a novel correction procedure. Experiment 1 co-recorded ERPs and trajectories of the articulators with an electromagnetic articulograph from a single participant. The generalization of the findings from the single participant to standard picture naming was investigated in Experiment 2. Both experiments provided evidence that articulation-induced artifacts may start up to 300 ms or more prior to voice onset or voice key onset-depending on the specific measure; they are highly similar in topography across many different phoneme patterns and differ mainly in their time course and amplitude. ERPs were separated from articulation-related artifacts with residue iteration decomposition (RIDE). After obtaining the artifact-free ERPs, their correlations with the articulatory trajectories dropped near to zero. Artifact removal with independent component analysis was less successful; while correlations with the articulatory movements remained substantial, early components prior to voice onset were attenuated in reconstructed ERPs. These findings offer new insights into the nature of articulation artifacts; together with RIDE as method for artifact removal the present report offers a fresh perspective for ERP studies requiring overt articulation.

Social context modulates cognitive markers in Obsessive-Compulsive Disorder.

PubMed

Santamaría-García, Hernando; Soriano-Mas, Carles; Burgaleta, Miguel; Ayneto, Alba; Alonso, Pino; Menchón, José M; Cardoner, Narcis; Sebastián-Gallés, Nuria

2017-08-03

Error monitoring, cognitive control and motor inhibition control are proposed as cognitive alterations disrupted in obsessive-compulsive disorder (OCD). OCD has also been associated with an increased sensitivity to social evaluations. The effect of a social simulation over electrophysiological indices of cognitive alterations in OCD was examined. A case-control cross-sectional study measuring event-related potentials (ERP) for error monitoring (Error-Related Negativity), cognitive control (N2) and motor control (LRP) was conducted. We analyzed twenty OCD patients and twenty control participants. ERP were recorded during a social game consisting of a visual discrimination task, which was performed in the presence of a simulated superior or an inferior player. Significant social effects (different ERP amplitudes in Superior vs. Inferior player conditions) were found for OCD patients, but not for controls, in all ERP components. Performing the task against a simulated inferior player reduced abnormal ERP responses in OCD to levels observed in controls. The hierarchy-induced ERP effects were accompanied effects over reaction times in OCD patients. Social context modulates signatures of abnormal cognitive functioning in OCD, therefore experiencing a social superiority position impacts over cognitive processes in OCD such as error monitoring mechanisms. These results open the door for the research of new therapeutic choices.

Association between waking electroencephalography and cognitive event-related potentials in patients with obstructive sleep apnea.

PubMed

Baril, Andrée-Ann; Gagnon, Katia; Gagnon, Jean-François; Montplaisir, Jacques; Gosselin, Nadia

2013-07-01

Sleepiness, cognitive deficits, abnormal event-related potentials (ERP), and slowing of the waking electroencephalography (EEG) activity have been reported in patients with obstructive sleep apnea (OSA). Our study aimed at evaluating if an association exists between the severity of ERP abnormalities and EEG slowing to better understand cerebral dysfunctions in OSA. Twelve OSA patients and 12 age-matched controls underwent an overnight polysomnographic recording, an EEG recording of 10 min of wakefulness, and an auditory ERP protocol known to specifically recruit attention. P300 and P3a ERP components were measured as well as the spectral power in each frequency band of the waking EEG. Pearson product moment correlations were used to measure associations between ERP characteristics and EEG spectral power in OSA patients and control subjects. A positive correlation between the late P300 amplitude and θ power in the occipital region was observed in OSA subjects (P<.01). A positive correlation was also found between P3a amplitude and β1 power in central region in OSA subjects (P<.01). No correlation was observed for control subjects. ERP abnormalities observed in an attention task are associated with a slowing of the waking EEG recorded at rest in OSA. Copyright © 2013 Elsevier B.V. All rights reserved.

ERP profiles for face and word recognition are based on their status in semantic memory not their stimulus category.

PubMed

Nie, Aiqing; Griffin, Michael; Keinath, Alexander; Walsh, Matthew; Dittmann, Andrea; Reder, Lynne

2014-04-04

Previous research has suggested that faces and words are processed and remembered differently as reflected by different ERP patterns for the two types of stimuli. Specifically, face stimuli produced greater late positive deflections for old items in anterior compared to posterior regions, while word stimuli produced greater late positive deflections in posterior compared to anterior regions. Given that words have existing representations in subjects׳ long-term memories (LTM) and that face stimuli used in prior experiments were of unknown individuals, we conducted an ERP study that crossed face and letter stimuli with the presence or absence of a prior (stable or existing) memory representation. During encoding, subjects judged whether stimuli were known (famous face or real word) or not known (unknown person or pseudo-word). A surprise recognition memory test required subjects to distinguish between stimuli that appeared during the encoding phase and stimuli that did not. ERP results were consistent with previous research when comparing unknown faces and words; however, the late ERP pattern for famous faces was more similar to that for words than for unknown faces. This suggests that the critical ERP difference is mediated by whether there is a prior representation in LTM, and not whether the stimulus involves letters or faces. Published by Elsevier B.V.

Low-Level Contrast Statistics of Natural Images Can Modulate the Frequency of Event-Related Potentials (ERP) in Humans.

PubMed

Ghodrati, Masoud; Ghodousi, Mahrad; Yoonessi, Ali

2016-01-01

Humans are fast and accurate in categorizing complex natural images. It is, however, unclear what features of visual information are exploited by brain to perceive the images with such speed and accuracy. It has been shown that low-level contrast statistics of natural scenes can explain the variance of amplitude of event-related potentials (ERP) in response to rapidly presented images. In this study, we investigated the effect of these statistics on frequency content of ERPs. We recorded ERPs from human subjects, while they viewed natural images each presented for 70 ms. Our results showed that Weibull contrast statistics, as a biologically plausible model, explained the variance of ERPs the best, compared to other image statistics that we assessed. Our time-frequency analysis revealed a significant correlation between these statistics and ERPs' power within theta frequency band (~3-7 Hz). This is interesting, as theta band is believed to be involved in context updating and semantic encoding. This correlation became significant at ~110 ms after stimulus onset, and peaked at 138 ms. Our results show that not only the amplitude but also the frequency of neural responses can be modulated with low-level contrast statistics of natural images and highlights their potential role in scene perception.

Low-Level Contrast Statistics of Natural Images Can Modulate the Frequency of Event-Related Potentials (ERP) in Humans

PubMed Central

Ghodrati, Masoud; Ghodousi, Mahrad; Yoonessi, Ali

2016-01-01

Humans are fast and accurate in categorizing complex natural images. It is, however, unclear what features of visual information are exploited by brain to perceive the images with such speed and accuracy. It has been shown that low-level contrast statistics of natural scenes can explain the variance of amplitude of event-related potentials (ERP) in response to rapidly presented images. In this study, we investigated the effect of these statistics on frequency content of ERPs. We recorded ERPs from human subjects, while they viewed natural images each presented for 70 ms. Our results showed that Weibull contrast statistics, as a biologically plausible model, explained the variance of ERPs the best, compared to other image statistics that we assessed. Our time-frequency analysis revealed a significant correlation between these statistics and ERPs' power within theta frequency band (~3–7 Hz). This is interesting, as theta band is believed to be involved in context updating and semantic encoding. This correlation became significant at ~110 ms after stimulus onset, and peaked at 138 ms. Our results show that not only the amplitude but also the frequency of neural responses can be modulated with low-level contrast statistics of natural images and highlights their potential role in scene perception. PMID:28018197

ERP=Efficiency

ERIC Educational Resources Information Center

Violino, Bob

2008-01-01

This article discusses the enterprise resource planning (ERP) system. Deploying an ERP system is one of the most extensive--and expensive--IT projects a college or university can undertake. The potential benefits of ERP are significant: a more smoothly running operation with efficiencies in virtually every area of administration, from automated…

Synergistic nonuniform shortening of atrial refractory period induced by autonomic stimulation.

PubMed

Takei, M; Furukawa, Y; Narita, M; Ren, L M; Karasawa, Y; Murakami, M; Chiba, S

1991-12-01

We investigated the nonuniform effects of autonomic nerve stimulation of the effective refractory period (ERP) of the right atrium in the anesthetized dog. Stimulation of the discrete intracardiac sympathetic nerves to the sinoatrial (SA) nodal region uniformly shortened ERPs at three sites in the right atrium after administration of atropine. Right ansa subclavia (RS) stimulation similarly shortened ERPs in the absence of atropine. Stimulation of the discrete intracardiac parasympathetic nerves to the SA nodal region (SAP stimulation) shortened ERPs of the right atrium in a nonuniform manner. Simultaneous RS and SAP stimulation additively shortened ERPs at each site and decreased sinus rate much more than SAP stimulation alone. Shortening of ERP induced by SAP stimulation was greater than that induced by RS stimulation at similar absolute changes in heart rate. These results suggest that simultaneous activation of sympathetic and parasympathetic nerves nonuniformly shortens the ERP in the right atrium as the algebraic sum of the individual responses to each stimulation. However, parasympathetics exert the principal neural control over atrial ERP.

ERP Software Implementation Best Practices.

ERIC Educational Resources Information Center

Frantz, Pollyanne S.; Southerland, Arthur R.; Johnson, James T.

2002-01-01

Studied the perceptions of chief financial and information officers of enterprise resource planning (ERP) software implementation best practices. Usable responses from 159 respondents show consensus for the most part between the perceptions of the two groups and describe some best practices that represent common ground. (SLD)

47 CFR 73.525 - TV Channel 6 protection.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... (4) The maximum permissible effective radiated power (ERP) and antenna height may be adjusted for..., the maximum permissible vertically polarized ERP will be the maximum horizontally polarized ERP... it does not. (ii) If the applicant chooses to use mixed polarity, the permissible ERP is as follows...

ERP correlates of object recognition memory in Down syndrome: Do active and passive tasks measure the same thing?

PubMed

Van Hoogmoed, A H; Nadel, L; Spanò, G; Edgin, J O

2016-02-01

Event related potentials (ERPs) can help to determine the cognitive and neural processes underlying memory functions and are often used to study populations with severe memory impairment. In healthy adults, memory is typically assessed with active tasks, while in patient studies passive memory paradigms are generally used. In this study we examined whether active and passive continuous object recognition tasks measure the same underlying memory process in typically developing (TD) adults and in individuals with Down syndrome (DS), a population with known hippocampal impairment. We further explored how ERPs in these tasks relate to behavioral measures of memory. Data-driven analysis techniques revealed large differences in old-new effects in the active versus passive task in TD adults, but no difference between these tasks in DS. The group with DS required additional processing in the active task in comparison to the TD group in two ways. First, the old-new effect started 150 ms later. Second, more repetitions were required to show the old-new effect. In the group with DS, performance on a behavioral measure of object-location memory was related to ERP measures across both tasks. In total, our results suggest that active and passive ERP memory measures do not differ in DS and likely reflect the use of implicit memory, but not explicit processing, on both tasks. Our findings highlight the need for a greater understanding of the comparison between active and passive ERP paradigms before they are inferred to measure similar functions across populations (e.g., infants or intellectual disability). Copyright © 2016 Elsevier Ltd. All rights reserved.

The Use of Brain Electrophysiology Techniques To Study Language: A Basic Guide for the Beginning Consumer of Electrophysiology Information.

ERIC Educational Resources Information Center

Molfese, Dennis L.; Molfese, Victoria J.; Kelly, Spencer

2001-01-01

This article provides an introduction to the use of event-related potential (ERP) approaches to study language processes. First, a brief history of the emergence of this technology is presented, followed by definitions, a theoretical overview, and a practical guide to conducting ERP studies. Examples of language studies that use this technique are…

Quantifying fast optical signal and event-related potential relationships during a visual oddball task.

PubMed

Proulx, Nicole; Samadani, Ali-Akbar; Chau, Tom

2018-05-16

Event-related potentials (ERPs) have previously been used to confirm the existence of the fast optical signal (FOS) but validation methods have mainly been limited to exploring the temporal correspondence of FOS peaks to those of ERPs. The purpose of this study was to systematically quantify the relationship between FOS and ERP responses to a visual oddball task in both time and frequency domains. Near-infrared spectroscopy (NIRS) and electroencephalography (EEG) sensors were co-located over the prefrontal cortex while participants performed a visual oddball task. Fifteen participants completed 2 data collection sessions each, where they were instructed to keep a mental count of oddball images. The oddball condition produced a positive ERP at 200 ms followed by a negativity 300-500 ms after image onset in the frontal electrodes. In contrast to previous FOS studies, a FOS response was identified only in DC intensity signals and not in phase delay signals. A decrease in DC intensity was found 150-250 ms after oddball image onset with a 400-trial average in 10 of 15 participants. The latency of the positive 200 ms ERP and the FOS DC intensity decrease were significantly correlated for only 6 (out of 15) participants due to the low signal-to-noise ratio of the FOS response. Coherence values between the FOS and ERP oddball responses were found to be significant in the 3-5 Hz frequency band for 10 participants. A significant Granger causal influence of the ERP on the FOS oddball response was uncovered in the 2-6 Hz frequency band for 7 participants. Collectively, our findings suggest that, for a majority of participants, the ERP and the DC intensity signal of the FOS are spectrally coherent, specifically in narrow frequency bands previously associated with event-related oscillations in the prefrontal cortex. However, these electro-optical relationships were only found in a subset of participants. Further research on enhancing the quality of the event-related FOS signal is required before it can be practically exploited in applications such as brain-computer interfacing. Copyright © 2018. Published by Elsevier Inc.

Risk assessment for enterprise resource planning (ERP) system implementations: a fault tree analysis approach

NASA Astrophysics Data System (ADS)

Zeng, Yajun; Skibniewski, Miroslaw J.

2013-08-01

Enterprise resource planning (ERP) system implementations are often characterised with large capital outlay, long implementation duration, and high risk of failure. In order to avoid ERP implementation failure and realise the benefits of the system, sound risk management is the key. This paper proposes a probabilistic risk assessment approach for ERP system implementation projects based on fault tree analysis, which models the relationship between ERP system components and specific risk factors. Unlike traditional risk management approaches that have been mostly focused on meeting project budget and schedule objectives, the proposed approach intends to address the risks that may cause ERP system usage failure. The approach can be used to identify the root causes of ERP system implementation usage failure and quantify the impact of critical component failures or critical risk events in the implementation process.

Recognition memory advantage for negative emotional words has an early expiry date: Evidence from brain oscillations and ERPs.

PubMed

Santaniello, G; Ferré, P; Rodríguez-Gómez, P; Poch, C; Eva, M Moreno; Hinojosa, J A

2018-06-15

Evidence from prior studies has shown an advantage in recognition memory for emotional compared to neutral words. Whether this advantage is short-lived or rather extends over longer periods, as well as whether the effect depends on words' valence (i.e., positive or negative), remains unknown. In the present ERP/EEG study, we investigated this issue by manipulating the lag distance (LAG-2, LAG-8 and LAG-16) between the presentation of old and new words in an online recognition memory task. LAG differences were observed at behavior, ERPs and in the theta frequency band. In line with previous studies, negative words were associated with faster reaction times, higher hit rates and increased amplitude in a positive ERP component between 386 and 564 ms compared to positive and neutral words. Remarkably, the interaction of LAG by EMOTION revealed that negative words were associated with better performance and larger ERPs amplitudes only at LAG-2. Also in the LAG-2 condition, emotional words (i.e., positive and negative words) induced a stronger desynchronization in the beta band between 386 and 542 ms compared to neutral words. These early enhanced memory effects for emotional words are discussed in terms of the Negative Emotional Valence Enhances Recapitulation (NEVER) model and the mobilization-minimization hypothesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of facial attractiveness on personality stimuli in an implicit priming task: an ERP study.

PubMed

Zhang, Yan; Zheng, Minxiao; Wang, Xiaoying

2016-08-01

Using event-related potentials (ERPs) in a priming paradigm, this study examines implicit priming in the association of personality words with facial attractiveness. A total of 16 participants (8 males and 8 females; age range, 19-24 years; mean age, 21.30 years) were asked to judge the color (red and green) of positive or negative personality words after exposure to priming stimuli (attractive and unattractive facial images). The positive personality words primed by attractive faces or the negative personality words primed by unattractive faces were defined as congruent trials, whereas the positive personality words primed by unattractive faces or the negative personality words primed by attractive faces were defined as incongruent trials. Behavioral results showed that compared with the unattractive faces trials, the trials that attractive faces being the priming stimuli had longer reaction times and higher accuracy rates. Moreover, a more negative ERP deflection (N2) component was observed in the ERPs of the incongruent condition than in the ERPs of the congruent condition. In addition, the personality words presented after the attractive faces elicited larger amplitudes from the frontal region to the central region (P2 and P350-550 ms) compared with the personality words after unattractive faces as priming stimuli. The study provides evidence for the facial attractiveness stereotype ('What is beautiful is good') through an implicit priming task.

Dysfunctional information processing in individuals with acute exposure to sexual abuse: An ERP study.

PubMed

Han, Changwoo; Park, Minkyung; Lee, Jun-Young; Jung, Hee Yeon; Park, Su Mi; Choi, Jung-Seok

2018-06-01

Acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) may occur after traumatic event and also cause significant life time impairment. P300 event-related potential (ERP) is a potential biological marker for PTSD and can reflect cognitive impairment in information processing and attention. Despite the usefulness of ERP, there are few attempts to reveal relationships between ASD and P300. In the present study, we aimed to determine if the P300 of the patients who were the victims of sexual abuse reflected the quantitative trait of ASD or if P300 is applicable as a state marker for predicting the risk of PTSD.Fifteen female victims of sexual abuse diagnosed with ASD and 18 healthy controls (HCs) without trauma exposure participated in this study. We investigated the P300 ERPs in patients with ASD to compare them with those of HCs. ERPs were acquired from female adults during an auditory oddball task. Between-group differences in amplitudes or latencies of P300 were investigated using repeated-measures analysis of variance.The ASD groups showed reduced P300 amplitudes at the midline centroparietal site as well as reduced accuracy rates during an auditory oddball task compared with the HCs.These results indicate that ASD have abnormalities in the P300 compared to those in HCs. Moreover, the reduction in P300 could be considered a candidate neurophysiological marker for ASD.

Sequential Processing and the Matching-Stimulus Interval Effect in ERP Components: An Exploration of the Mechanism Using Multiple Regression

PubMed Central

Steiner, Genevieve Z.; Barry, Robert J.; Gonsalvez, Craig J.

2016-01-01

In oddball tasks, increasing the time between stimuli within a particular condition (target-to-target interval, TTI; nontarget-to-nontarget interval, NNI) systematically enhances N1, P2, and P300 event-related potential (ERP) component amplitudes. This study examined the mechanism underpinning these effects in ERP components recorded from 28 adults who completed a conventional three-tone oddball task. Bivariate correlations, partial correlations and multiple regression explored component changes due to preceding ERP component amplitudes and intervals found within the stimulus series, rather than constraining the task with experimentally constructed intervals, which has been adequately explored in prior studies. Multiple regression showed that for targets, N1 and TTI predicted N2, TTI predicted P3a and P3b, and Processing Negativity (PN), P3b, and TTI predicted reaction time. For rare nontargets, P1 predicted N1, NNI predicted N2, and N1 predicted Slow Wave (SW). Findings show that the mechanism is operating on separate stages of stimulus-processing, suggestive of either increased activation within a number of stimulus-specific pathways, or very long component generator recovery cycles. These results demonstrate the extent to which matching-stimulus intervals influence ERP component amplitudes and behavior in a three-tone oddball task, and should be taken into account when designing similar studies. PMID:27445774

Sequential Processing and the Matching-Stimulus Interval Effect in ERP Components: An Exploration of the Mechanism Using Multiple Regression.

PubMed

Steiner, Genevieve Z; Barry, Robert J; Gonsalvez, Craig J

2016-01-01

In oddball tasks, increasing the time between stimuli within a particular condition (target-to-target interval, TTI; nontarget-to-nontarget interval, NNI) systematically enhances N1, P2, and P300 event-related potential (ERP) component amplitudes. This study examined the mechanism underpinning these effects in ERP components recorded from 28 adults who completed a conventional three-tone oddball task. Bivariate correlations, partial correlations and multiple regression explored component changes due to preceding ERP component amplitudes and intervals found within the stimulus series, rather than constraining the task with experimentally constructed intervals, which has been adequately explored in prior studies. Multiple regression showed that for targets, N1 and TTI predicted N2, TTI predicted P3a and P3b, and Processing Negativity (PN), P3b, and TTI predicted reaction time. For rare nontargets, P1 predicted N1, NNI predicted N2, and N1 predicted Slow Wave (SW). Findings show that the mechanism is operating on separate stages of stimulus-processing, suggestive of either increased activation within a number of stimulus-specific pathways, or very long component generator recovery cycles. These results demonstrate the extent to which matching-stimulus intervals influence ERP component amplitudes and behavior in a three-tone oddball task, and should be taken into account when designing similar studies.

Auditory P300 event related potentials in acute and transient psychosis-Comparison with schizophrenia.

PubMed

Sahoo, Swapnajeet; Malhotra, Savita; Basu, Debasish; Modi, Manish

2016-10-01

Limited biological research data are available on acute and transient psychotic disorder (ATPD) vis-à-vis schizophrenia. P300 event related potentials (ERP) have been extensively studied as an important neurophysiological parameter in schizophrenia. However, no P300 ERP studies comparing the two disorders are available. We compared auditory P300 ERP in patients remitted from ATPD with schizophrenia in remission and biologically unrelated healthy controls. In this case-control study design, 25 subjects remitted from ATPD were age-/gender-matched with healthy controls and patients with schizophrenia in remission. Clinical assessment and auditory P300 ERP (amplitude and latencies at central and parietal sites, reaction time) were recorded. The ERP parameters were compared across the three groups. All three groups showed significant differences in P300 amplitudes and latencies at central and parietal sites. Schizophrenia group differed significantly (p<0.001) from the ATPD group in all the P300 parameters. The ATPD group was found to have lower Pz latency (p<0.05) and lower mean reaction time (p<0.001) as compared to healthy controls. The results suggest that P300 could easily distinguish between ATPD and schizophrenia in remission, thus neurophysiologically differentiating the two disorders. Lower P300 latency and reaction time, which indicate hyper-arousability, distinguished ATPD from normal controls, with implications for a better understanding of ATPD. Copyright © 2016 Elsevier B.V. All rights reserved.

Cannabis with high δ9-THC contents affects perception and visual selective attention acutely: an event-related potential study.

PubMed

Böcker, K B E; Gerritsen, J; Hunault, C C; Kruidenier, M; Mensinga, Tj T; Kenemans, J L

2010-07-01

Cannabis intake has been reported to affect cognitive functions such as selective attention. This study addressed the effects of exposure to cannabis with up to 69.4mg Delta(9)-tetrahydrocannabinol (THC) on Event-Related Potentials (ERPs) recorded during a visual selective attention task. Twenty-four participants smoked cannabis cigarettes with four doses of THC on four test days in a randomized, double blind, placebo-controlled, crossover study. Two hours after THC exposure the participants performed a visual selective attention task and concomitant ERPs were recorded. Accuracy decreased linearly and reaction times increased linearly with THC dose. However, performance measures and most of the ERP components related specifically to selective attention did not show significant dose effects. Only in relatively light cannabis users the Occipital Selection Negativity decreased linearly with dose. Furthermore, ERP components reflecting perceptual processing, as well as the P300 component, decreased in amplitude after THC exposure. Only the former effect showed a linear dose-response relation. The decrements in performance and ERP amplitudes induced by exposure to cannabis with high THC content resulted from a non-selective decrease in attentional or processing resources. Performance requiring attentional resources, such as vehicle control, may be compromised several hours after smoking cannabis cigarettes containing high doses of THC, as presently available in Europe and Northern America. Copyright 2010 Elsevier Inc. All rights reserved.

47 CFR 22.659 - Effective radiated power limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... radiated power limits. The purpose of the rules in this section, which limit effective radiated power (ERP... subsequently relocated. (a) Maximum ERP. The ERP of base transmitters must not exceed 100 Watts under any circumstances. The ERP of mobile transmitters must not exceed 60 Watts under any circumstances. (b) Co-channel...

47 CFR 22.913 - Effective radiated power limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... radiated power (ERP) of transmitters in the Cellular Radiotelephone Service must not exceed the limits in this section. (a) Maximum ERP. In general, the effective radiated power (ERP) of base transmitters and... areas, as those areas are defined in § 22.949, the ERP of base transmitters and cellular repeaters of...

The Implications of Real Options on ERP-Enabled Adoption

ERIC Educational Resources Information Center

Nwankpa, Joseph K.

2012-01-01

Current research on Enterprise Resource Planning (ERP) systems and real options focuses on valuation and justification issues that manager's face prior to project approval with existing literature attempting to demonstrate that ERP systems as technology positioning investments have option-like characteristics thus making such ERP systems…

RELATIONSHIP OF LATE POSITIVE ERPS (EVENT-RELATED POTENTIALS), AGE, INTELLIGENCE AND LEAD ABSORPTION IN SOCIOECONOMICALLY DISADVANTAGED CHILDREN

EPA Science Inventory

Children from socioeconomically disadvantaged families are at risk for malnutrition, learning disabilities, and many other problems associated with poverty. Increasing application of event-related potentials (ERP) methods has been made in studies of aberrant development, although...

The effect of a brief mindfulness induction on processing of emotional images: an ERP study.

PubMed

Eddy, Marianna D; Brunyé, Tad T; Tower-Richardi, Sarah; Mahoney, Caroline R; Taylor, Holly A

2015-01-01

The ability to effectively direct one's attention is an important aspect of regulating emotions and a component of mindfulness. Mindfulness practices have been established as effective interventions for mental and physical illness; however, the underlying neural mechanisms of mindfulness and how they relate to emotional processing have not been explored in depth. The current study used a within-subjects repeated measures design to examine if focused breathing, a brief mindfulness induction, could modulate event-related potentials (ERPs) during emotional image processing relative to a control condition. We related ERP measures of processing positive, negative, and neutral images (the P300 and late positive potential - LPP) to state and trait mindfulness measures. Overall, the brief mindfulness induction condition did not influence ERPs reflecting emotional processing; however, in the brief mindfulness induction condition, those participants who reported feeling more decentered (a subscale of the Toronto Mindfulness Scale) after viewing the images had reduced P300 responses to negative versus neutral images.

Stability of auditory discrimination and novelty processing in physiological aging.

PubMed

Raggi, Alberto; Tasca, Domenica; Rundo, Francesco; Ferri, Raffaele

2013-01-01

Complex higher-order cognitive functions and their possible changes with aging are mandatory objectives of cognitive neuroscience. Event-related potentials (ERPs) allow investigators to probe the earliest stages of information processing. N100, Mismatch negativity (MMN) and P3a are auditory ERP components that reflect automatic sensory discrimination. The aim of the present study was to determine if N100, MMN and P3a parameters are stable in healthy aged subjects, compared to those of normal young adults. Normal young adults and older participants were assessed using standardized cognitive functional instruments and their ERPs were obtained with an auditory stimulation at two different interstimulus intervals, during a passive paradigm. All individuals were within the normal range on cognitive tests. No significant differences were found for any ERP parameters obtained from the two age groups. This study shows that aging is characterized by a stability of the auditory discrimination and novelty processing. This is important for the arrangement of normative for the detection of subtle preclinical changes due to abnormal brain aging.

Integration of fMRI, NIROT and ERP for studies of human brain function.

PubMed

Gore, John C; Horovitz, Silvina G; Cannistraci, Christopher J; Skudlarski, Pavel

2006-05-01

Different methods of assessing human brain function possess specific advantages and disadvantages compared to others, but it is believed that combining different approaches will provide greater information than can be obtained from each alone. For example, functional magnetic resonance imaging (fMRI) has good spatial resolution but poor temporal resolution, whereas the converse is true for electrophysiological recordings (event-related potentials or ERPs). In this review of recent work, we highlight a novel approach to combining these modalities in a manner designed to increase information on the origins and locations of the generators of specific ERPs and the relationship between fMRI and ERP signals. Near infrared imaging techniques have also been studied as alternatives to fMRI and can be readily integrated with simultaneous electrophysiological recordings. Each of these modalities may in principle be also used in so-called steady-state acquisitions in which the correlational structure of signals from the brain may be analyzed to provide new insights into brain function.

The effect of a brief mindfulness induction on processing of emotional images: an ERP study

PubMed Central

Eddy, Marianna D.; Brunyé, Tad T.; Tower-Richardi, Sarah; Mahoney, Caroline R.; Taylor, Holly A.

2015-01-01

The ability to effectively direct one’s attention is an important aspect of regulating emotions and a component of mindfulness. Mindfulness practices have been established as effective interventions for mental and physical illness; however, the underlying neural mechanisms of mindfulness and how they relate to emotional processing have not been explored in depth. The current study used a within-subjects repeated measures design to examine if focused breathing, a brief mindfulness induction, could modulate event-related potentials (ERPs) during emotional image processing relative to a control condition. We related ERP measures of processing positive, negative, and neutral images (the P300 and late positive potential – LPP) to state and trait mindfulness measures. Overall, the brief mindfulness induction condition did not influence ERPs reflecting emotional processing; however, in the brief mindfulness induction condition, those participants who reported feeling more decentered (a subscale of the Toronto Mindfulness Scale) after viewing the images had reduced P300 responses to negative versus neutral images. PMID:26441766

An event-related potential study of semantic style-match judgments of artistic furniture.

PubMed

Lin, Ming-Huang; Wang, Ching-yi; Cheng, Shih-kuen; Cheng, Shih-hung

2011-11-01

This study investigates how semantic networks represent different artistic furniture. Event-related potentials (ERPs) were recorded while participants made style-match judgments for table and chair sets. All of the tables were in the Normal style, whereas the chairs were in the Normal, Minimal, ReadyMade, or Deconstruction styles. The Normal and Minimal chairs had the same rates of "match" responses, which were both higher than the rates for the ReadyMade and Deconstruction chairs. Compared with Normal chairs, the ERPs elicited by both ReadyMade chairs and Deconstruction chairs exhibited reliable N400 effects, which suggests that these two design styles were unlike the Normal design style. However, Minimal chairs evoked ERPs that were similar to the ERPs of Normal chairs. Furthermore, the N400 effects elicited by ReadyMade and Deconstruction chairs showed different scalp distributions. These findings reveal that semantic networks represent different design styles for items of the same category. Copyright © 2011 Elsevier B.V. All rights reserved.

Static renewal tests using Pimephales promelas (fathead minnows) and Ceriodaphnia dubia (daphnids). Clinch River-Environmental Restoration Program (CR-ERP) pilot study, ambient water toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simbeck, D.J.

1993-12-31

Clinch River-Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a pilot study during the week of April 22--29, 1993, prior to initiation of CR-ERP Phase 2 Sampling and Analysis activities. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 9.0 and Poplar Creek Kilometer 1.6 on April 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in nomore » toxicity (survival, growth, or reproduction) to either species in testing conducted by TVA. Attachments to this report include: Chain of custody forms -- originals; Toxicity test bench sheets and statistical analyses; Reference toxicant test information; and Personnel training documentation.« less

Processing Biological Gender and Number Information during Chinese Pronoun Resolution: ERP Evidence for Functional Differentiation

ERIC Educational Resources Information Center

Xu, Xiaodong; Jiang, Xiaoming; Zhou, Xiaolin

2013-01-01

There have been a number of behavioral and neural studies on the processing of syntactic gender and number agreement information, marked by different morpho-syntactic features during sentence comprehension. By using the event-related potential (ERP) technique, the present study investigated whether the processing of semantic gender information and…

Use of Event-Related Potentials in the Study of Typical and Atypical Development

ERIC Educational Resources Information Center

Nelson, Charles A., III; McCleery, Joseph P.

2008-01-01

Event-related potential is a kind of neuroimaging tool which can be used in the study of neurodevelopment. Two areas of atypical development, children diagnosed with autism and children experiencing early psychosocial neglect, have benefited from ERPs. The physiological basis of ERPs and the constraints on their applications are also discussed.

Integrating Enterprise Resource Planning (SAP) in the Accounting Curriculum: A Systematic Literature Review and Case Study

ERIC Educational Resources Information Center

Blount, Yvette; Abedin, Babak; Vatanasakdakul, Savanid; Erfani, Seyedezahra

2016-01-01

This study investigates how an enterprise resource planning (ERP) software package SAP was integrated into the curriculum of an accounting information systems (AIS) course in an Australian university. Furthermore, the paper provides a systematic literature review of articles published between 1990 and 2013 to understand how ERP systems were…

A Comparison of Semantic and Syntactic Event Related Potentials Generated by Children and Adults

ERIC Educational Resources Information Center

Atchley, Ruth Ann; Rice, Mabel L.; Betz, Stacy K.; Kwasny, Kristin M.; Sereno, Joan A.; Jongman, Allard

2006-01-01

The present study employs event related potentials (ERPs) to verify the utility of using electrophysiological measures to study developmental questions within the field of language comprehension. Established ERP components (N400 and P600) that reflect semantic and syntactic processing were examined. Fifteen adults and 14 children (ages 8-13)…

Decomposing Animacy Reversals between Agents and Experiencers: An ERP Study

ERIC Educational Resources Information Center

Bourguignon, Nicolas; Drury, John E.; Valois, Daniel; Steinhauer, Karsten

2012-01-01

The present study aimed to refine current hypotheses regarding thematic reversal anomalies, which have been found to elicit either N400 or--more frequently--"semantic-P600" (sP600) effects. Our goal was to investigate whether distinct ERP profiles reflect aspectual-thematic differences between Agent-Subject Verbs (ASVs; e.g., "to eat") and…

A novel EOG/EEG hybrid human-machine interface adopting eye movements and ERPs: application to robot control.

PubMed

Ma, Jiaxin; Zhang, Yu; Cichocki, Andrzej; Matsuno, Fumitoshi

2015-03-01

This study presents a novel human-machine interface (HMI) based on both electrooculography (EOG) and electroencephalography (EEG). This hybrid interface works in two modes: an EOG mode recognizes eye movements such as blinks, and an EEG mode detects event related potentials (ERPs) like P300. While both eye movements and ERPs have been separately used for implementing assistive interfaces, which help patients with motor disabilities in performing daily tasks, the proposed hybrid interface integrates them together. In this way, both the eye movements and ERPs complement each other. Therefore, it can provide a better efficiency and a wider scope of application. In this study, we design a threshold algorithm that can recognize four kinds of eye movements including blink, wink, gaze, and frown. In addition, an oddball paradigm with stimuli of inverted faces is used to evoke multiple ERP components including P300, N170, and VPP. To verify the effectiveness of the proposed system, two different online experiments are carried out. One is to control a multifunctional humanoid robot, and the other is to control four mobile robots. In both experiments, the subjects can complete tasks effectively by using the proposed interface, whereas the best completion time is relatively short and very close to the one operated by hand.

Examining ERP correlates of recognition memory: Evidence of accurate source recognition without recollection

PubMed Central

Addante, Richard, J.; Ranganath, Charan; Yonelinas, Andrew, P.

2012-01-01

Recollection is typically associated with high recognition confidence and accurate source memory. However, subjects sometimes make accurate source memory judgments even for items that are not confidently recognized, and it is not known whether these responses are based on recollection or some other memory process. In the current study, we measured event related potentials (ERPs) while subjects made item and source memory confidence judgments in order to determine whether recollection supported accurate source recognition responses for items that were not confidently recognized. In line with previous studies, we found that recognition memory was associated with two ERP effects: an early on-setting FN400 effect, and a later parietal old-new effect [Late Positive Component (LPC)], which have been associated with familiarity and recollection, respectively. The FN400 increased gradually with item recognition confidence, whereas the LPC was only observed for highly confident recognition responses. The LPC was also related to source accuracy, but only for items that had received a high confidence item recognition response; accurate source judgments to items that were less confidently recognized did not exhibit the typical ERP correlate of recollection or familiarity, but rather showed a late, broadly distributed negative ERP difference. The results indicate that accurate source judgments of episodic context can occur even when recollection fails. PMID:22548808

ERP correlates of attention allocation in mothers processing faces of their children

PubMed Central

Grasso, Damion J.; Moser, Jason S.; Dozier, Mary; Simons, Robert

2012-01-01

This study employed visually evoked event-related potential (ERP) methodology to examine temporal patterns of structural and higher-level face processing in birth and foster/adoptive mothers viewing pictures of their children. Fourteen birth mothers and 14 foster/adoptive mothers engaged in a computerized task in which they viewed facial pictures of their own children, and of familiar and unfamiliar children and adults. All mothers, regardless of type, showed ERP patterns suggestive of increased attention allocation to their own children’s faces compared to other child and adult faces beginning as early as 100–150 ms after stimulus onset and lasting for several hundred milliseconds. These data are in line with a parallel processing model that posits the involvement of several brain regions in simultaneously encoding the structural features of faces as well as their emotional and personal significance. Additionally, late positive ERP patterns associated with greater allocation of attention predicted mothers’ perceptions of the parent–child relationship as positive and influential to their children’s psychological development. These findings suggest the potential utility of using ERP components to index maternal processes. PMID:19428973

P2 and behavioral effects of stroke count in Chinese characters: Evidence for an analytic and attentional view.

PubMed

Yang, Shasha; Zhang, Shunmei; Wang, Quanhong

2016-08-15

The inconsistent stroke-count effect in Chinese character recognition has resulted in an intense debate between the analytic and holistic views of character processing. The length effects of English words on behavioral responses and event-related potentials (ERPs) are similarly inconclusive. In this study, we identified any behavioral and ERP stroke-count effects when orthographic neighborhood sizes are balanced across three stroke counts. A delayed character-matching task was conducted while ERPs were recorded. The behavioral data indicated that both response latency and error rate increased with increasing stroke count. The ERP data showed higher P2 but lower N2 amplitudes in the large count than in the median count condition. A higher P2 can reflect increased attentional load and reduced attentional resource for processing each stroke because of the additional strokes in the large count condition. The behavioral and ERP effects of stroke count provide evidence for the analytic view of character processing but also provide evidence against the holistic view. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The dissociable neural dynamics of cognitive conflict and emotional conflict control: An ERP study.

PubMed

Xue, Song; Li, Yu; Kong, Xia; He, Qiaolin; Liu, Jia; Qiu, Jiang

2016-04-21

This study investigated differences in the neural time-course of cognitive conflict and emotional conflict control, using event-related potentials (ERPs). Although imaging studies have provided some evidence that distinct, dissociable neural systems underlie emotional and nonemotional conflict resolution, no ERP study has directly compared these two types of conflict. Therefore, the present study used a modified face-word Stroop task to explore the electrophysiological correlates of cognitive and emotional conflict control. The behavioral data showed that the difference in response time of congruency (incongruent condition minus the congruent condition) was larger in the cognitive conflict task than in the emotional conflict task, which indicated that cognitive conflict was stronger than the emotional conflict in the present tasks. Analysis of the ERP data revealed a main effect of task type on N2, which may be associated with top-down attention. The N450 results showed an interaction between cognitive and emotional conflict, which might be related to conflict detection. In addition, we found the incongruent condition elicited a larger SP than the congruent condition, which might be related to conflict resolution. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Individual differences in the recognition of facial expressions: an event-related potentials study.

PubMed

Tamamiya, Yoshiyuki; Hiraki, Kazuo

2013-01-01

Previous studies have shown that early posterior components of event-related potentials (ERPs) are modulated by facial expressions. The goal of the current study was to investigate individual differences in the recognition of facial expressions by examining the relationship between ERP components and the discrimination of facial expressions. Pictures of 3 facial expressions (angry, happy, and neutral) were presented to 36 young adults during ERP recording. Participants were asked to respond with a button press as soon as they recognized the expression depicted. A multiple regression analysis, where ERP components were set as predictor variables, assessed hits and reaction times in response to the facial expressions as dependent variables. The N170 amplitudes significantly predicted for accuracy of angry and happy expressions, and the N170 latencies were predictive for accuracy of neutral expressions. The P2 amplitudes significantly predicted reaction time. The P2 latencies significantly predicted reaction times only for neutral faces. These results suggest that individual differences in the recognition of facial expressions emerge from early components in visual processing.

Are females more responsive to emotional stimuli? A neurophysiological study across arousal and valence dimensions.

PubMed

Lithari, C; Frantzidis, C A; Papadelis, C; Vivas, Ana B; Klados, M A; Kourtidou-Papadeli, C; Pappas, C; Ioannides, A A; Bamidis, P D

2010-03-01

Men and women seem to process emotions and react to them differently. Yet, few neurophysiological studies have systematically investigated gender differences in emotional processing. Here, we studied gender differences using Event Related Potentials (ERPs) and Skin Conductance Responses (SCR) recorded from participants who passively viewed emotional pictures selected from the International Affective Picture System (IAPS). The arousal and valence dimension of the stimuli were manipulated orthogonally. The peak amplitude and peak latency of ERP components and SCR were analyzed separately, and the scalp topographies of significant ERP differences were documented. Females responded with enhanced negative components (N100 and N200), in comparison to males, especially to the unpleasant visual stimuli, whereas both genders responded faster to high arousing or unpleasant stimuli. Scalp topographies revealed more pronounced gender differences on central and left hemisphere areas. Our results suggest a difference in the way emotional stimuli are processed by genders: unpleasant and high arousing stimuli evoke greater ERP amplitudes in women relatively to men. It also seems that unpleasant or high arousing stimuli are temporally prioritized during visual processing by both genders.

Optimizing Within-Subject Experimental Designs for jICA of Multi-Channel ERP and fMRI

PubMed Central

Mangalathu-Arumana, Jain; Liebenthal, Einat; Beardsley, Scott A.

2018-01-01

Joint independent component analysis (jICA) can be applied within subject for fusion of multi-channel event-related potentials (ERP) and functional magnetic resonance imaging (fMRI), to measure brain function at high spatiotemporal resolution (Mangalathu-Arumana et al., 2012). However, the impact of experimental design choices on jICA performance has not been systematically studied. Here, the sensitivity of jICA for recovering neural sources in individual data was evaluated as a function of imaging SNR, number of independent representations of the ERP/fMRI data, relationship between instantiations of the joint ERP/fMRI activity (linear, non-linear, uncoupled), and type of sources (varying parametrically and non-parametrically across representations of the data), using computer simulations. Neural sources were simulated with spatiotemporal and noise attributes derived from experimental data. The best performance, maximizing both cross-modal data fusion and the separation of brain sources, occurred with a moderate number of representations of the ERP/fMRI data (10–30), as in a mixed block/event related experimental design. Importantly, the type of relationship between instantiations of the ERP/fMRI activity, whether linear, non-linear or uncoupled, did not in itself impact jICA performance, and was accurately recovered in the common profiles (i.e., mixing coefficients). Thus, jICA provides an unbiased way to characterize the relationship between ERP and fMRI activity across brain regions, in individual data, rendering it potentially useful for characterizing pathological conditions in which neurovascular coupling is adversely affected. PMID:29410611

Tracking the voluntary control of auditory spatial attention with event-related brain potentials.

PubMed

Störmer, Viola S; Green, Jessica J; McDonald, John J

2009-03-01

A lateralized event-related potential (ERP) component elicited by attention-directing cues (ADAN) has been linked to frontal-lobe control but is often absent when spatial attention is deployed in the auditory modality. Here, we tested the hypothesis that ERP activity associated with frontal-lobe control of auditory spatial attention is distributed bilaterally by comparing ERPs elicited by attention-directing cues and neutral cues in a unimodal auditory task. This revealed an initial ERP positivity over the anterior scalp and a later ERP negativity over the parietal scalp. Distributed source analysis indicated that the anterior positivity was generated primarily in bilateral prefrontal cortices, whereas the more posterior negativity was generated in parietal and temporal cortices. The anterior ERP positivity likely reflects frontal-lobe attentional control, whereas the subsequent ERP negativity likely reflects anticipatory biasing of activity in auditory cortex.

Does processing a shallow and a deep orthography produce different brain activity patterns? An ERP study conducted in Hebrew.

PubMed

Bar-Kochva, Irit

2011-01-01

Orthographies range from shallow orthographies with transparent grapheme-phoneme relations, to deep orthographies, in which these relations are opaque. Two forms of script transcribe the Hebrew language: the shallow pointed script (with diacritics) and the deep unpointed script (without diacritics). This study was set out to examine whether the reading of these scripts evokes distinct brain activity. Preliminary results indicate distinct Event-related-potentials (ERPs). As an equivalent finding was absent when ERPs of non-orthographic stimuli with and without meaningless diacritics were compared, the results imply that print-specific aspects of processing account for the distinct activity elicited by the pointed and unpointed scripts.

47 CFR 22.727 - Power limits for conventional rural radiotelephone transmitters.

Code of Federal Regulations, 2011 CFR

2011-10-01

... this section. (a) Maximum ERP. The effective radiated power (ERP) of central office and rural... circumstances. Frequency range (MHz) Maximum ERP (watts) 152-153 1400 157-159 150 454-455 3500 459-460 150 (b) Basic power limit. Except as provided in paragraph (d) of this section, the ERP of central office...

47 CFR 22.727 - Power limits for conventional rural radiotelephone transmitters.

Code of Federal Regulations, 2010 CFR

2010-10-01

... this section. (a) Maximum ERP. The effective radiated power (ERP) of central office and rural... circumstances. Frequency range (MHz) Maximum ERP (watts) 152-153 1400 157-159 150 454-455 3500 459-460 150 (b) Basic power limit. Except as provided in paragraph (d) of this section, the ERP of central office...

47 CFR 22.535 - Effective radiated power limits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... limits. The effective radiated power (ERP) of transmitters operating on the channels listed in § 22.531 must not exceed the limits in this section. (a) Maximum ERP. The ERP must not exceed the applicable limits in this paragraph under any circumstances. Frequency range (MHz) Maximum ERP (Watts) 35-36 600 43...

47 CFR 22.535 - Effective radiated power limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... limits. The effective radiated power (ERP) of transmitters operating on the channels listed in § 22.531 must not exceed the limits in this section. (a) Maximum ERP. The ERP must not exceed the applicable limits in this paragraph under any circumstances. Frequency range (MHz) Maximum ERP (Watts) 35-36 600 43...

Is Open Source the ERP Cure-All?

ERIC Educational Resources Information Center

Panettieri, Joseph C.

2008-01-01

Conventional and hosted applications thrive, but open source ERP (enterprise resource planning) is coming on strong. In many ways, the evolution of the ERP market is littered with ironies. When Oracle began buying up customer relationship management (CRM) and ERP companies, some universities worried that they would be left with fewer choices and…

Single-trial event-related potential extraction through one-unit ICA-with-reference

NASA Astrophysics Data System (ADS)

Lih Lee, Wee; Tan, Tele; Falkmer, Torbjörn; Leung, Yee Hong

2016-12-01

Objective. In recent years, ICA has been one of the more popular methods for extracting event-related potential (ERP) at the single-trial level. It is a blind source separation technique that allows the extraction of an ERP without making strong assumptions on the temporal and spatial characteristics of an ERP. However, the problem with traditional ICA is that the extraction is not direct and is time-consuming due to the need for source selection processing. In this paper, the application of an one-unit ICA-with-Reference (ICA-R), a constrained ICA method, is proposed. Approach. In cases where the time-region of the desired ERP is known a priori, this time information is utilized to generate a reference signal, which is then used for guiding the one-unit ICA-R to extract the source signal of the desired ERP directly. Main results. Our results showed that, as compared to traditional ICA, ICA-R is a more effective method for analysing ERP because it avoids manual source selection and it requires less computation thus resulting in faster ERP extraction. Significance. In addition to that, since the method is automated, it reduces the risks of any subjective bias in the ERP analysis. It is also a potential tool for extracting the ERP in online application.

Single-trial event-related potential extraction through one-unit ICA-with-reference.

PubMed

Lee, Wee Lih; Tan, Tele; Falkmer, Torbjörn; Leung, Yee Hong

2016-12-01

In recent years, ICA has been one of the more popular methods for extracting event-related potential (ERP) at the single-trial level. It is a blind source separation technique that allows the extraction of an ERP without making strong assumptions on the temporal and spatial characteristics of an ERP. However, the problem with traditional ICA is that the extraction is not direct and is time-consuming due to the need for source selection processing. In this paper, the application of an one-unit ICA-with-Reference (ICA-R), a constrained ICA method, is proposed. In cases where the time-region of the desired ERP is known a priori, this time information is utilized to generate a reference signal, which is then used for guiding the one-unit ICA-R to extract the source signal of the desired ERP directly. Our results showed that, as compared to traditional ICA, ICA-R is a more effective method for analysing ERP because it avoids manual source selection and it requires less computation thus resulting in faster ERP extraction. In addition to that, since the method is automated, it reduces the risks of any subjective bias in the ERP analysis. It is also a potential tool for extracting the ERP in online application.

Functional Role of the Disulfide Isomerase ERp57 in Axonal Regeneration.

PubMed

Castillo, Valentina; Oñate, Maritza; Woehlbier, Ute; Rozas, Pablo; Andreu, Catherine; Medinas, Danilo; Valdés, Pamela; Osorio, Fabiola; Mercado, Gabriela; Vidal, René L; Kerr, Bredford; Court, Felipe A; Hetz, Claudio

2015-01-01

ERp57 (also known as grp58 and PDIA3) is a protein disulfide isomerase that catalyzes disulfide bonds formation of glycoproteins as part of the calnexin and calreticulin cycle. ERp57 is markedly upregulated in most common neurodegenerative diseases downstream of the endoplasmic reticulum (ER) stress response. Despite accumulating correlative evidence supporting a neuroprotective role of ERp57, the contribution of this foldase to the physiology of the nervous system remains unknown. Here we developed a transgenic mouse model that overexpresses ERp57 in the nervous system under the control of the prion promoter. We analyzed the susceptibility of ERp57 transgenic mice to undergo neurodegeneration. Unexpectedly, ERp57 overexpression did not affect dopaminergic neuron loss and striatal denervation after injection of a Parkinson's disease-inducing neurotoxin. In sharp contrast, ERp57 transgenic animals presented enhanced locomotor recovery after mechanical injury to the sciatic nerve. These protective effects were associated with enhanced myelin removal, macrophage infiltration and axonal regeneration. Our results suggest that ERp57 specifically contributes to peripheral nerve regeneration, whereas its activity is dispensable for the survival of a specific neuronal population of the central nervous system. These results demonstrate for the first time a functional role of a component of the ER proteostasis network in peripheral nerve regeneration.

Diet and Gender Influences on Processing and Discrimination of Speech Sounds in 3- and 6-Month-Old Infants: A Developmental ERP Study

ERIC Educational Resources Information Center

Pivik, R. T.; Andres, Aline; Badger, Thomas M.

2011-01-01

Early post-natal nutrition influences later development, but there are no studies comparing brain function in healthy infants as a function of dietary intake even though the major infant diets differ significantly in nutrient composition. We studied brain responses (event-related potentials; ERPs) to speech sounds for infants who were fed either…

Multivariate Genetic Correlates of the Auditory Paired Stimuli-Based P2 Event-Related Potential in the Psychosis Dimension From the BSNIP Study.

PubMed

Mokhtari, Mohammadreza; Narayanan, Balaji; Hamm, Jordan P; Soh, Pauline; Calhoun, Vince D; Ruaño, Gualberto; Kocherla, Mohan; Windemuth, Andreas; Clementz, Brett A; Tamminga, Carol A; Sweeney, John A; Keshavan, Matcheri S; Pearlson, Godfrey D

2016-05-01

The complex molecular etiology of psychosis in schizophrenia (SZ) and psychotic bipolar disorder (PBP) is not well defined, presumably due to their multifactorial genetic architecture. Neurobiological correlates of psychosis can be identified through genetic associations of intermediate phenotypes such as event-related potential (ERP) from auditory paired stimulus processing (APSP). Various ERP components of APSP are heritable and aberrant in SZ, PBP and their relatives, but their multivariate genetic factors are less explored. We investigated the multivariate polygenic association of ERP from 64-sensor auditory paired stimulus data in 149 SZ, 209 PBP probands, and 99 healthy individuals from the multisite Bipolar-Schizophrenia Network on Intermediate Phenotypes study. Multivariate association of 64-channel APSP waveforms with a subset of 16 999 single nucleotide polymorphisms (SNPs) (reduced from 1 million SNP array) was examined using parallel independent component analysis (Para-ICA). Biological pathways associated with the genes were assessed using enrichment-based analysis tools. Para-ICA identified 2 ERP components, of which one was significantly correlated with a genetic network comprising multiple linearly coupled gene variants that explained ~4% of the ERP phenotype variance. Enrichment analysis revealed epidermal growth factor, endocannabinoid signaling, glutamatergic synapse and maltohexaose transport associated with P2 component of the N1-P2 ERP waveform. This ERP component also showed deficits in SZ and PBP. Aberrant P2 component in psychosis was associated with gene networks regulating several fundamental biologic functions, either general or specific to nervous system development. The pathways and processes underlying the gene clusters play a crucial role in brain function, plausibly implicated in psychosis. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Cortical responses from adults and infants to complex visual stimuli.

PubMed

Schulman-Galambos, C; Galambos, R

1978-10-01

Event-related potentials (ERPs) time-locked to the onset of visual stimuli were extracted from the EEG of normal adult (N = 16) and infant (N = 23) subjects. Subjects were not required to make any response. Stimuli delivered to the adults were 150 msec exposures of 2 sets of colored slides projected in 4 blocks, 2 in focus and 2 out of focus. Infants received 2-sec exposures of slides showing people, colored drawings or scenes from Disneyland, as well as 2-sec illuminations of the experimenter as she played a game or of a TV screen the baby was watching. The adult ERPs showed 6 waves (N1 through P4) in the 140--600-msec range; this included a positive wave at around 350 msec that was large when the stimuli were focused and smaller when they were not. The waves in the 150--200-msec range, by contrast, steadily dropped in amplitude as the experiment progressed. The infant ERPs differed greatly from the adult ones in morphology, usually showing a positive (latency about 200 msec)--negative(5--600msec)--positive(1000msec) sequence. This ERP appeared in all the stimulus conditions; its presence or absence, furthermore, was correlated with whether or not the baby seemed interested in the stimuli. Four infants failed to produce these ERPs; an independent measure of attention to the stimuli, heart rate deceleration, was demonstrated in two of them. An electrode placed beneath the eye to monitor eye movements yielded ERPs closely resembling those derived from the scalp in most subjects; reasons are given for assigning this response to activity in the brain, probably at the frontal pole. This study appears to be one of the first to search for cognitive 'late waves' in a no-task situation. The results suggest that further work with such task-free paradigms may yield additional useful techniques for studying the ERP.

Kernel PLS Estimation of Single-trial Event-related Potentials

NASA Technical Reports Server (NTRS)

Rosipal, Roman; Trejo, Leonard J.

2004-01-01

Nonlinear kernel partial least squaes (KPLS) regressior, is a novel smoothing approach to nonparametric regression curve fitting. We have developed a KPLS approach to the estimation of single-trial event related potentials (ERPs). For improved accuracy of estimation, we also developed a local KPLS method for situations in which there exists prior knowledge about the approximate latency of individual ERP components. To assess the utility of the KPLS approach, we compared non-local KPLS and local KPLS smoothing with other nonparametric signal processing and smoothing methods. In particular, we examined wavelet denoising, smoothing splines, and localized smoothing splines. We applied these methods to the estimation of simulated mixtures of human ERPs and ongoing electroencephalogram (EEG) activity using a dipole simulator (BESA). In this scenario we considered ongoing EEG to represent spatially and temporally correlated noise added to the ERPs. This simulation provided a reasonable but simplified model of real-world ERP measurements. For estimation of the simulated single-trial ERPs, local KPLS provided a level of accuracy that was comparable with or better than the other methods. We also applied the local KPLS method to the estimation of human ERPs recorded in an experiment on co,onitive fatigue. For these data, the local KPLS method provided a clear improvement in visualization of single-trial ERPs as well as their averages. The local KPLS method may serve as a new alternative to the estimation of single-trial ERPs and improvement of ERP averages.

The novel white spot syndrome virus-induced gene, PmERP15, encodes an ER stress-responsive protein in black tiger shrimp, Penaeus monodon.

PubMed

Leu, Jiann-Horng; Liu, Kuan-Fu; Chen, Kuan-Yu; Chen, Shu-Hwa; Wang, Yu-Bin; Lin, Chung-Yen; Lo, Chu-Fang

2015-04-01

By microarray screening, we identified a white spot syndrome virus (WSSV)-strongly induced novel gene in gills of Penaeus monodon. The gene, PmERP15, encodes a putative transmembrane protein of 15 kDa, which only showed some degree of similarity (54-59%) to several unknown insect proteins, but had no hits to shrimp proteins. RT-PCR showed that PmERP15 was highly expressed in the hemocytes, heart and lymphoid organs, and that WSSV-induced strong expression of PmERP15 was evident in all tissues examined. Western blot analysis likewise showed that WSSV strongly up-regulated PmERP15 protein levels. In WSSV-infected hemocytes, immunofluorescence staining showed that PmERP15 protein was colocalized with an ER enzyme, protein disulfide isomerase, and in Sf9 insect cells, PmERP15-EGFP fusion protein colocalized with ER -Tracker™ Red dye as well. GRP78, an ER stress marker, was found to be up-regulated in WSSV-infected P. monodon, and both PmERP15 and GRP78 were up-regulated in shrimp injected with ER stress inducers tunicamycin and dithiothreitol. Silencing experiments showed that although PmERP15 dsRNA-injected shrimp succumbed to WSSV infection more rapidly, the WSSV copy number had no significant changes. These results suggest that PmERP15 is an ER stress-induced, ER resident protein, and its induction in WSSV-infected shrimp is caused by the ER stress triggered by WSSV infection. Furthermore, although PmERP15 has no role in WSSV multiplication, its presence is essential for the survival of WSSV-infected shrimp. Copyright © 2014 Elsevier Ltd. All rights reserved.

Enhanced Recovery after Colorectal Surgery: Can We Afford Not to Use It?

PubMed

Jung, Andrew D; Dhar, Vikrom K; Hoehn, Richard S; Atkinson, Sarah J; Johnson, Bobby L; Rice, Teresa; Snyder, Jonathan R; Rafferty, Janice F; Edwards, Michael J; Paquette, Ian M

2018-04-01

Enhanced recovery pathways (ERPs) aim to reduce length of stay without adversely affecting short-term outcomes. High pharmaceutical costs associated with ERP regimens, however, remain a significant barrier to widespread implementation. We hypothesized that ERP would reduce hospital costs after elective colorectal resections, despite the use of more expensive pharmaceutical agents. An ERP was implemented in January 2016 at our institution. We collected data on consecutive colorectal resections for 1 year before adoption of ERP (traditional, n = 160) and compared them with consecutive resections after universal adoption of ERP (n = 146). Short-term surgical outcomes, total direct costs, and direct hospital pharmacy costs were compared between patients who received the ERP and those who did not. After implementation of the ERP, median length of stay decreased from 5.0 to 3.0 days (p < 0.01). There were no differences in 30-day complications (8.1% vs 8.9%) or hospital readmission (11.9% vs 11.0%). The ERP patients required significantly less narcotics during their index hospitalization (211.7 vs 720.2 morphine equivalence units; p < 0.01) and tolerated a regular diet 1 day sooner (p < 0.01). Despite a higher daily pharmacy cost ($477 per day vs $318 per day in the traditional cohort), the total direct pharmacy cost for the hospitalization was reduced in ERP patients ($1,534 vs $1,859; p = 0.016). Total direct cost was also lower in ERP patients ($9,791 vs $11,508; p = 0.004). Implementation of an ERP for patients undergoing elective colorectal resection substantially reduced length of stay, total hospital cost, and direct pharmacy cost without increasing complications or readmission rates. Enhanced recovery pathway after colorectal resection has both clinical and financial benefits. Widespread implementation has the potential for a dramatic impact on healthcare costs. Copyright © 2018 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Event-related-potential low-resolution brain electromagnetic tomography (ERP-LORETA) suggests decreased energetic resources for cognitive processing in narcolepsy.

PubMed

Saletu, Michael; Anderer, Peter; Saletu-Zyhlarz, Gerda Maria; Mandl, Magdalena; Zeitlhofer, Josef; Saletu, Bernd

2008-08-01

Event-related potentials (ERPs) are sensitive measures of both perceptual and cognitive processes. The aim of the present study was to identify brain regions involved in the processes of cognitive dysfunction in narcolepsy by means of ERP tomography. In 17 drug-free patients with narcolepsy and 17 controls, ERPs were recorded (auditory odd-ball paradigm). Latencies, amplitudes and LORETA sources were determined for standard (N1 and P2) and target (N2 and P300) ERP components. Psychometry included measures of mental performance, affect and critical flicker fusion frequency (CFF). In the ERPs patients demonstrated delayed cognitive N2 and P300 components and reduced amplitudes in midline regions, while N1 and P2 components did not differ from controls. LORETA suggested reduced P300 sources bilaterally in the precuneus, the anterior and posterior cingulate gyri, the ventrolateral prefrontal cortex and the parahippocampal gyrus. In psychometry, patients demonstrated deteriorated mood, increased trait anxiety, decreased CFF and a trend toward reduced general verbal memory and psychomotor activity. Narcoleptic patients showed prolonged information processing, as indexed by N2 and P300 latencies and decreased energetic resources for cognitive processing. Electrophysiological aberrations in brain areas related to the 'executive attention network' and the 'limbic system' may contribute to a deterioration in mental performance and mood at the behavioral level.

Fusion with Language Models Improves Spelling Accuracy for ERP-based Brain Computer Interface Spellers

PubMed Central

Orhan, Umut; Erdogmus, Deniz; Roark, Brian; Purwar, Shalini; Hild, Kenneth E.; Oken, Barry; Nezamfar, Hooman; Fried-Oken, Melanie

2013-01-01

Event related potentials (ERP) corresponding to a stimulus in electroencephalography (EEG) can be used to detect the intent of a person for brain computer interfaces (BCI). This paradigm is widely utilized to build letter-by-letter text input systems using BCI. Nevertheless using a BCI-typewriter depending only on EEG responses will not be sufficiently accurate for single-trial operation in general, and existing systems utilize many-trial schemes to achieve accuracy at the cost of speed. Hence incorporation of a language model based prior or additional evidence is vital to improve accuracy and speed. In this paper, we study the effects of Bayesian fusion of an n-gram language model with a regularized discriminant analysis ERP detector for EEG-based BCIs. The letter classification accuracies are rigorously evaluated for varying language model orders as well as number of ERP-inducing trials. The results demonstrate that the language models contribute significantly to letter classification accuracy. Specifically, we find that a BCI-speller supported by a 4-gram language model may achieve the same performance using 3-trial ERP classification for the initial letters of the words and using single trial ERP classification for the subsequent ones. Overall, fusion of evidence from EEG and language models yields a significant opportunity to increase the word rate of a BCI based typing system. PMID:22255652

Mismatched expressions decrease face recognition and corresponding ERP old/new effects in schizophrenia.

PubMed

Guillaume, Fabrice; Guillem, François; Tiberghien, Guy; Stip, Emmanuel

2012-09-01

The objective was to investigate the electrophysiological (ERP) correlates of mismatched expression on face recognition in schizophrenia. Expression-change effects and associated ERPs were explored in patients with schizophrenia (n = 20) and paired comparison participants (n = 20) on a long-term face-recognition task. A facial-expression change decreased discriminability for patients with schizophrenia than for healthy participants. The patients' recognition deficit was accompanied by the absence of the midfrontal FN400 and late parietal ERP old/new effects in the mismatched-expression condition. By contrast, preserved midfrontal FN400 and late parietal ERP old/new effects were found in both groups in the unchanged-expression condition. Thus, the preserved parietal old/new effect previously observed in schizophrenia was no longer found here in the situation in which expression changes took place between the study and recognition phases. These findings suggest that, when they are not supposed to take the change of expression into account, the recognition deficit observed here in patients with schizophrenia resulted from an impairment in the mechanisms underlying the emergence, assessment, or utilization of familiarity--as indexed by the ERP old/new effects. In these natural conditions, the impact of the expression change on the implementation of retrieval processes offers new insight into schizophrenia-linked deficits in face recognition, with substantial phenomenological differences with respect to the emergence of familiarity.

Latency correction of event-related potentials between different experimental protocols

NASA Astrophysics Data System (ADS)

Iturrate, I.; Chavarriaga, R.; Montesano, L.; Minguez, J.; Millán, JdR

2014-06-01

Objective. A fundamental issue in EEG event-related potentials (ERPs) studies is the amount of data required to have an accurate ERP model. This also impacts the time required to train a classifier for a brain-computer interface (BCI). This issue is mainly due to the poor signal-to-noise ratio and the large fluctuations of the EEG caused by several sources of variability. One of these sources is directly related to the experimental protocol or application designed, and may affect the amplitude or latency of ERPs. This usually prevents BCI classifiers from generalizing among different experimental protocols. In this paper, we analyze the effect of the amplitude and the latency variations among different experimental protocols based on the same type of ERP. Approach. We present a method to analyze and compensate for the latency variations in BCI applications. The algorithm has been tested on two widely used ERPs (P300 and observation error potentials), in three experimental protocols in each case. We report the ERP analysis and single-trial classification. Main results. The results obtained show that the designed experimental protocols significantly affect the latency of the recorded potentials but not the amplitudes. Significance. These results show how the use of latency-corrected data can be used to generalize the BCIs, reducing the calibration time when facing a new experimental protocol.

Decreased ERp57 Expression in WAG/Rij Rats Thalamus and Cortex; Possible Correlation with Absence Epilepsy.

PubMed

Sahin, Deniz; Karadenizli, Sabriye; Kasap, Murat; Oztas, Berrin; Kir, Hale Maral; Akpinar, Gurler; Ates, Nurbay

2018-02-06

The role of intracellular proteins in the pathogenesis of absence epilepsy were mentioned. These proteins are thought to be related to energy generation, signal transduction, inflammation processes and membrane conductance. The investigation of protein profile of the genetically epileptic rat brains was the main subject of this study. For this, a 2D-gel electrophoresis based comparative proteome analysis was performed using thalamus tissue of genetic absence epileptic WAG/Rij and age matched Wistar rats. Regulated spots displaying differences in their abundance were identified using MALDI-TOF/TOF. Among the six spots (DHRS9, BR44, HINT1, CREM, SPRE and PDIA3/ERp57) the highest mascot score was attributed to ERp57 a neuroprotective/neurodegenerative system associated protein. Western Blot analyses were performed to validate changes occurring at ERp57 in thalamus and also identify changes in fronto-parietal cortex. Reductions in the expression levels of ERp57 were detected in the thalamic and the fronto-parietal brain regions of the WAG/Rij rats in comparison to Wistar rats. Such difference might be associated with the pathogenic mechanisms dictating the absence epilepsy. Lower levels of ERp57 may be playing an important role in the development of spontaneous seizures activity seen in the absence epileptic WAG/Rij rats strain. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Machine Learning EEG to Predict Cognitive Functioning and Processing Speed Over a 2-Year Period in Multiple Sclerosis Patients and Controls.

PubMed

Kiiski, Hanni; Jollans, Lee; Donnchadha, Seán Ó; Nolan, Hugh; Lonergan, Róisín; Kelly, Siobhán; O'Brien, Marie Claire; Kinsella, Katie; Bramham, Jessica; Burke, Teresa; Hutchinson, Michael; Tubridy, Niall; Reilly, Richard B; Whelan, Robert

2018-05-01

Event-related potentials (ERPs) show promise to be objective indicators of cognitive functioning. The aim of the study was to examine if ERPs recorded during an oddball task would predict cognitive functioning and information processing speed in Multiple Sclerosis (MS) patients and controls at the individual level. Seventy-eight participants (35 MS patients, 43 healthy age-matched controls) completed visual and auditory 2- and 3-stimulus oddball tasks with 128-channel EEG, and a neuropsychological battery, at baseline (month 0) and at Months 13 and 26. ERPs from 0 to 700 ms and across the whole scalp were transformed into 1728 individual spatio-temporal datapoints per participant. A machine learning method that included penalized linear regression used the entire spatio-temporal ERP to predict composite scores of both cognitive functioning and processing speed at baseline (month 0), and months 13 and 26. The results showed ERPs during the visual oddball tasks could predict cognitive functioning and information processing speed at baseline and a year later in a sample of MS patients and healthy controls. In contrast, ERPs during auditory tasks were not predictive of cognitive performance. These objective neurophysiological indicators of cognitive functioning and processing speed, and machine learning methods that can interrogate high-dimensional data, show promise in outcome prediction.

Cognitive aspects of nociception and pain: bridging neurophysiology with cognitive psychology.

PubMed

Legrain, V; Mancini, F; Sambo, C F; Torta, D M; Ronga, I; Valentini, E

2012-10-01

The event-related brain potentials (ERPs) elicited by nociceptive stimuli are largely influenced by vigilance, emotion, alertness, and attention. Studies that specifically investigated the effects of cognition on nociceptive ERPs support the idea that most of these ERP components can be regarded as the neurophysiological indexes of the processes underlying detection and orientation of attention toward the eliciting stimulus. Such detection is determined both by the salience of the stimulus that makes it pop out from the environmental context (bottom-up capture of attention) and by its relevance according to the subject's goals and motivation (top-down attentional control). The fact that nociceptive ERPs are largely influenced by information from other sensory modalities such as vision and proprioception, as well as from motor preparation, suggests that these ERPs reflect a cortical system involved in the detection of potentially meaningful stimuli for the body, with the purpose to respond adequately to potential threats. In such a theoretical framework, pain is seen as an epiphenomenon of warning processes, encoded in multimodal and multiframe representations of the body, well suited to guide defensive actions. The findings here reviewed highlight that the ERPs elicited by selective activation of nociceptors may reflect an attentional gain apt to bridge a coherent perception of salient sensory events with action selection processes. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Prediction in Language Comprehension beyond Specific Words: An ERP Study on Sentence Comprehension in Polish

ERIC Educational Resources Information Center

Szewczyk, Jakub M.; Schriefers, Herbert

2013-01-01

Recently, several ERP studies have shown that the human language comprehension system anticipates words that are highly likely continuations of a given text. However, it remains an open issue whether the language comprehension system can also make predictions that go beyond a specific word. Here, we address the question of whether readers predict…

Investigation of Effects of Face Rotation on Race Processing: An ERPs Study

ERIC Educational Resources Information Center

Montalan, Benoit; Veujoz, Mathieu; Boitout, Alexis; Leleu, Arnaud; Camus, Odile; Lalonde, Robert; Rebai, Mohamed

2013-01-01

Recent ERP research has indicated that the processing of faces of other races (OR) and same race (SR) as the perceiver differs at the perceptual level, more precisely for the N170 component. The purpose of the present study was to continue the investigation of the race-of-face processing across multiple orientations. Event-related brain potentials…

Semantic memory processing is enhanced in preadolescents breastfed compared to those formula-fed as infants: An ERP N400 study of sentential semantic congruity

USDA-ARS?s Scientific Manuscript database

Studies comparing child cognitive development and brain activity during cognitive functions between children who were fed breast milk (BF), milk formula (MF), or soy formula (SF) have not been reported. We recorded event-related scalp potentials reflecting semantic processing (N400 ERP) from 20 homo...

Anodonta imbecillis QA Test 2, Clinch River - Environmental Restoration Program (CR-ERP)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simbeck, D.J.

1997-06-01

Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Atiodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected August 14 from Poplar Creek Miles 6.0 and 4.3 was conducted from August 24-September 2, 1993. Results from this test showed no toxicity (survival effects) to fresh--water mussels during a 9-day exposure to the sediments.

Anodonta imbecillis QA Test 3, Clinch River - Environmental Restoration Program (CR-ERP)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simbeck, D.J.

1997-06-01

Toxicity testing of split whole sediment samples using juvenile freshwater mussels (Anodonta imbecillis) was conducted by TVA to provide a quality assurance mechanism for test organism quality and overall performance of the test being conducted by CR-ERP personnel as part of the CR-ERP biomonitoring study of Clinch River sediments. Testing of sediment samples collected May 5 from Poplar Creek Miles 6.0 and 2.9 was conducted from May 10-19, 1994. Results from this test showed no toxicity (survival effects) to fresh-water mussels during a 9-day exposure to the sediments.

Acceptance and Success Factors for M-Learning of ERP Systems Curricula

ERIC Educational Resources Information Center

Scholtz, Brenda; Kapeso, Mando

2014-01-01

The effective training of users is a key factor of the success of Enterprise Resource Planning (ERP) system projects. This need for ERP system training is exacerbated by a demand for quality ERP consultants which is evident in Europe and in African countries, particularly in South Africa where science and technology education has been identified…

Exploring the Effects of Technology Overload on the Outcomes of Enterprise Resource Planning (ERP) Implementation Projects

ERIC Educational Resources Information Center

Kates, Earl B.

2016-01-01

Despite significant investments made by organizations to implement ERP systems and prior research that explored contributing factors of ERP failure, the ERP implementation success rate continues to remain low in practice. Increased technology usage in the workplace coupled with higher dependency on technology to complete project tasks often leads…

The influence of enterprise resource planning (ERP) systems' performance on earnings management

NASA Astrophysics Data System (ADS)

Tsai, Wen-Hsien; Lee, Kuen-Chang; Liu, Jau-Yang; Lin, Sin-Jin; Chou, Yu-Wei

2012-11-01

We analyse whether there is a linkage between performance measures of enterprise resource planning (ERP) systems and earnings management. We find that earnings management decreases with the higher performance of ERP systems. The empirical result is as expected. We further analyse how the dimension of the DeLone and McLean model of information systems success affects earnings management. We find that the relationship between the performance of ERP systems and earnings management depends on System Quality after ERP implementation. The more System Quality improves, the more earnings management is reduced.

ERP (enterprise resource planning) systems can streamline healthcare business functions.

PubMed

Jenkins, E K; Christenson, E

2001-05-01

Enterprise resource planning (ERP) software applications are designed to facilitate the systemwide integration of complex processes and functions across a large enterprise consisting of many internal and external constituents. Although most currently available ERP applications generally are tailored to the needs of the manufacturing industry, many large healthcare systems are investigating these applications. Due to the significant differences between manufacturing and patient care, ERP-based systems do not easily translate to the healthcare setting. In particular, the lack of clinical standardization impedes the use of ERP systems for clinical integration. Nonetheless, an ERP-based system can help a healthcare organization integrate many functions, including patient scheduling, human resources management, workload forecasting, and management of workflow, that are not directly dependent on clinical decision making.

Event-Related Brain Potential Correlates of Emotional Face Processing

ERIC Educational Resources Information Center

Eimer, Martin; Holmes, Amanda

2007-01-01

Results from recent event-related brain potential (ERP) studies investigating brain processes involved in the detection and analysis of emotional facial expression are reviewed. In all experiments, emotional faces were found to trigger an increased ERP positivity relative to neutral faces. The onset of this emotional expression effect was…

Business Simulations Applied in Support of ERP Training

ERIC Educational Resources Information Center

Conroy, George

2012-01-01

This quantitative, quasi-experimental study examined the application of a business simulation against training in support of an Enterprise Resource Planning (ERP) system. Defining more effective training strategies is a critical concern for organizational leaders and stakeholders concerned by today's economic challenges. The scope of this…

Can Clouds Dance? Part 2: An ERP Investigation of Passive Conceptual Expansion

ERIC Educational Resources Information Center

Rutter, Barbara; Kroger, Soren; Hill, Holger; Windmann, Sabine; Hermann, Christiane; Abraham, Anna

2012-01-01

Conceptual expansion, one of the core operations in creative cognition, was investigated in the present ERP study. An experimental paradigm using novel metaphoric, nonsensical and literal phrases was employed where individual differences in conceptual knowledge organization were accounted for by using participants' responses to categorize the…

Prefrontal Cortex Contributions to Episodic Retrieval Monitoring and Evaluation

ERIC Educational Resources Information Center

Cruse, Damian; Wilding, Edward L.

2009-01-01

Although the prefrontal cortex (PFC) plays roles in episodic memory judgments, the specific processes it supports are not understood fully. Event-related potential (ERP) studies of episodic retrieval have revealed an electrophysiological modulation--the right-frontal ERP old/new effect--which is thought to reflect activity in PFC. The functional…

Differences in Word Recognition between Early Bilinguals and Monolinguals: Behavioral and ERP Evidence

ERIC Educational Resources Information Center

Lehtonen, Minna; Hulten, Annika; Rodriguez-Fornells, Antoni; Cunillera, Toni; Tuomainen, Jyrki; Laine, Matti

2012-01-01

We investigated the behavioral and brain responses (ERPs) of bilingual word recognition to three fundamental psycholinguistic factors, frequency, morphology, and lexicality, in early bilinguals vs. monolinguals. Earlier behavioral studies have reported larger frequency effects in bilinguals' nondominant vs. dominant language and in some studies…

Memory Effects in Syntactic ERP Tasks

ERIC Educational Resources Information Center

Sabourin, Laura; Stowe, Laurie

2004-01-01

The study presented here investigated the role of memory in normal sentence processing by looking at ERP effects to normal sentences and sentences containing grammatical violations. Sentences where the critical word was in the middle of the sentence were compared to sentences where the critical word always occurred in sentence-final position.…

Neural correlates of emotional face processing in bipolar disorder: an event-related potential study.

PubMed

Degabriele, Racheal; Lagopoulos, Jim; Malhi, Gin

2011-09-01

Behavioural and imaging studies report that individuals with bipolar disorder (BD) exhibit impairments in emotional face processing. However, few studies have studied the temporal characteristics of these impairments, and event-related potential (ERP) studies that investigate emotion perception in BD are rare. The aim of our study was to explore these processes as indexed by the face-specific P100 and N170 ERP components in a BD cohort. Eighteen subjects diagnosed with BD and 18 age- and sex-matched healthy volunteers completed an emotional go/no-go inhibition task during electroencephalogram (EEG) and ERP acquisition. Patients demonstrated faster responses to happy compared to sad faces, whereas control data revealed no emotional discrimination. Errors of omission were more frequent in the BD group in both emotion conditions, but there were no between-group differences in commission errors. Significant differences were found between groups in P100 amplitude variation across levels of affect, with the BD group exhibiting greater responses to happy compared to sad faces. Conversely, the control cohort failed to demonstrate a differentiation between emotions. A statistically significant between-group effect was also found for N170 amplitudes, indicating reduced responses in the BD group. Future studies should ideally recruit BD patients across all three mood states (manic, depressive, and euthymic) with greater scrutiny of the effects of psychotropic medication. These ERP results primarily suggest an emotion-sensitive face processing impairment in BD whereby patients are initially more attuned to positive emotions as indicated by the P100 ERP component, and this may contribute to the emergence of bipolar-like symptoms. Copyright © 2011 Elsevier B.V. All rights reserved.

Integrated geophysical survey in defining subsidence features on a golf course

USGS Publications Warehouse

Xia, J.; Miller, R.D.

2007-01-01

Subsidence was observed at several places on the Salina Municipal Golf Course in areas known to be built over a landfill in Salina, Kansas. High-resolution magnetic survey (???5400 m2), multi-channel electrical resistivity profiling (three 154 m lines) and microgravity profiling (23 gravity-station values) were performed on a subsidence site (Green 16) to aid in determining boundaries and density deficiency of the landfill in the vicinity of the subsidence. Horizontal boundaries of the landfill were confidently defined by both magnetic anomalies and the pseudo-vertical gradient of total field magnetic anomalies. Furthermore, the pseudo-vertical gradient of magnetic anomalies presented a unique anomaly at Green 16, which provided a criterion for predicting other spots with subsidence potential using the same gradient property. Results of multi-channel electrical resistivity profiling (ERP) suggested the bottom limit of the landfill at Green 16 was around 21 m below the ground surface based on the vertical gradient of electric resistivity and a priori information on the depth of the landfill. ERP results also outlined several possible landfill bodies based on their low resistivity values. Microgravity results suggested a -0.14 g cm-3 density deficiency at Green 16 that could equate to future surface subsidence of as much as 1.5 m due to gradual compaction. ?? 2007 Nanjing Institute of Geophysical Prospecting.

From amnesia to dementia: ERP studies of memory and language.

PubMed

Taylor, Jason R; Olichney, John M

2007-01-01

Cognitive event-related potential (ERP) studies of memory and language impairments in amnesia and Alzheimer's disease (AD) are reviewed. Well-circumscribed lesions of the medial temporal lobe (MTL) or diencephalon causing an amnestic syndrome, an inability to encode and retrieve episodic memories beyond the brief duration of working memory, appear to produce altered plasticity of the late positive P600 component, but usually spare P300 and N400 components. The neuropathology of AD affects MTL and extends to neocortical association areas, causing deficits of episodic and semantic memory. In AD dementia, the P300, N400, and P600 all commonly show abnormalities. ERP studies of individuals with mild cognitive impairment may reveal neurophysiological changes prior to the emergence of clinical deficits, which could advance the early detection and diagnosis of AD.

Remodeling of atrial ATP-sensitive K+ channels in a model of salt-induced elevated blood pressure

PubMed Central

Lader, Joshua M.; Vasquez, Carolina; Bao, Li; Maass, Karen; Qu, Jiaxiang; Kefalogianni, Eirini; Fishman, Glenn I.; Coetzee, William A.

2011-01-01

Hypertension is associated with the development of atrial fibrillation; however, the electrophysiological consequences of this condition remain poorly understood. ATP-sensitive K+ (KATP) channels, which contribute to ventricular arrhythmias, are also expressed in the atria. We hypothesized that salt-induced elevated blood pressure (BP) leads to atrial KATP channel activation and increased arrhythmia inducibility. Elevated BP was induced in mice with a high-salt diet (HS) for 4 wk. High-resolution optical mapping was used to measure atrial arrhythmia inducibility, effective refractory period (ERP), and action potential duration at 90% repolarization (APD90). Excised patch clamping was performed to quantify KATP channel properties and density. KATP channel protein expression was also evaluated. Atrial arrhythmia inducibility was 22% higher in HS hearts compared with control hearts. ERP and APD90 were significantly shorter in the right atrial appendage and left atrial appendage of HS hearts compared with control hearts. Perfusion with 1 μM glibenclamide or 300 μM tolbutamide significantly decreased arrhythmia inducibility and prolonged APD90 in HS hearts compared with untreated HS hearts. KATP channel density was 156% higher in myocytes isolated from HS animals compared with control animals. Sulfonylurea receptor 1 protein expression was increased in the left atrial appendage and right atrial appendage of HS animals (415% and 372% of NS animals, respectively). In conclusion, KATP channel activation provides a mechanistic link between salt-induced elevated BP and increased atrial arrhythmia inducibility. The findings of this study have important implications for the treatment and prevention of atrial arrhythmias in the setting of hypertensive heart disease and may lead to new therapeutic approaches. PMID:21724863

Assessment of Cognitive Processing by Multiple Sclerosis Patients Using Electroencephalographic Energy Density Analysis

NASA Technical Reports Server (NTRS)

Montgomery, Leslie D.; Ku, Yu-Tsuan E.; Luna, Bernadette; Montgomery, Richard W.; Kliss, Mark (Technical Monitor)

1997-01-01

Recent neuropsychological studies demonstrate that cognitive dysfunction is a common symptom in patients with multiple sclerosis. In many cases the presence of cognitive impairment affects the patient's daily activities to a greater extent than would be found due to their physical disability alone. Cognitive dysfunction can have a significant impact on the quality of life of both the patient and that of their primary caregiver. Two cognitively impaired male MS patients were given a visual discrimination task before and after a one hour cooling period. The subjects were presented a series of either red or blue circles or triangles. One of these combinations, or one fourth of the stimuli, was designated as the "target" presentation. EEG was recorded from 20 scalp electrodes using a Tracor Northern 7500 EEG/ERP system. Oral and ear temperatures were obtained and recorded manually every five minutes during the one hour cooling period. The EEG ERP signatures from each series of stimuli were analyzed in the energy density domain to determine the locus of neural activity at each EEG sampling time. The first subject's ear temperature did not decrease during the cooling period. It was actually elevated approximately 0.05C by the end of the cooling period compared to his mean of control period value. In turn, Subject One's discrimination performance and cortical energy remained essentially the same after body cooling. In contrast, Subject Two's ear temperature decreased approx. 0.8C during his cooling period. Subject Two's ERROR score decreased from 12 during the precooling control period to 2 after cooling. His ENERGY value increased approximately 300%, from a precooling value of approximately 200 to a postcooling value of nearly 600.

Primary task event-related potentials related to different aspects of information processing

NASA Technical Reports Server (NTRS)

Munson, Robert C.; Horst, Richard L.; Mahaffey, David L.

1988-01-01

The results of two studies which investigated the relationships between cognitive processing and components of transient event-related potentials (ERPs) are presented in a task in which mental workload was manipulated. The task involved the monitoring of an array of discrete readouts for values that went out of bounds, and was somewhat analogous to tasks performed in cockpits. The ERPs elicited by the changing readouts varied with the number of readouts being monitored, the number of monitored readouts that were close to going out of bounds, and whether or not the change took a monitored readout out of bounds. Moreover, different regions of the waveform differentially reflected these effects. The results confirm the sensitivity of scalp-recorded ERPs to the cognitive processes affected by mental workload and suggest the possibility of extracting useful ERP indices of primary task performance in a wide range of man-machine settings.

Approximate entropy analysis of event-related potentials in patients with early vascular dementia.

PubMed

Xu, Jin; Sheng, Hengsong; Lou, Wutao; Zhao, Songzhen

2012-06-01

This study investigated differences in event-related potential (ERP) parameters among early vascular dementia (VD) patients, healthy elder controls (ECs), and young controls (YCs). A visual "oddball" color identification task was performed while individuals' electroencephalograms (EEGs) were recorded. Approximate entropy (ApEn), a nonlinear measure, along with P300 latencies and amplitudes were used to analyze ERP data and compare these three groups. The patients with VD showed more complex ERP waveforms and higher ApEn values than did ECs while performing the visual task. It was further found that patients with VD showed reduced P300 amplitudes and increased latencies. The results indicate that patients with VD have fewer attention resources to devote to processing stimuli, lower speed of stimulus classification, and lower synchrony in their cortical activity during the response period. We suggest that ApEn, as a measure of ERP complexity, is a promising marker for early diagnosis of VD.

Cognitive workload modulation through degraded visual stimuli: a single-trial EEG study

NASA Astrophysics Data System (ADS)

Yu, K.; Prasad, I.; Mir, H.; Thakor, N.; Al-Nashash, H.

2015-08-01

Objective. Our experiments explored the effect of visual stimuli degradation on cognitive workload. Approach. We investigated the subjective assessment, event-related potentials (ERPs) as well as electroencephalogram (EEG) as measures of cognitive workload. Main results. These experiments confirm that degradation of visual stimuli increases cognitive workload as assessed by subjective NASA task load index and confirmed by the observed P300 amplitude attenuation. Furthermore, the single-trial multi-level classification using features extracted from ERPs and EEG is found to be promising. Specifically, the adopted single-trial oscillatory EEG/ERP detection method achieved an average accuracy of 85% for discriminating 4 workload levels. Additionally, we found from the spatial patterns obtained from EEG signals that the frontal parts carry information that can be used for differentiating workload levels. Significance. Our results show that visual stimuli can modulate cognitive workload, and the modulation can be measured by the single trial EEG/ERP detection method.

An event-related brain potential study of visual selective attention to conjunctions of color and shape.

PubMed

Smid, H G; Jakob, A; Heinze, H J

1999-03-01

What cognitive processes underlie event-related brain potential (ERP) effects related to visual multidimensional selective attention and how are these processes organized? We recorded ERPs when participants attended to one conjunction of color, global shape and local shape and ignored other conjunctions of these attributes in three discriminability conditions. Attending to color and shape produced three ERP effects: frontal selection positivity (FSP), central negativity (N2b), and posterior selection negativity (SN). The results suggested that the processes underlying SN and N2b perform independent within-dimension selections, whereas the process underlying the FSP performs hierarchical between-dimension selections. At posterior electrodes, manipulation of discriminability changed the ERPs to the relevant but not to the irrelevant stimuli, suggesting that the SN does not concern the selection process itself but rather a cognitive process initiated after selection is finished. Other findings suggested that selection of multiple visual attributes occurs in parallel.

Code query by example

NASA Astrophysics Data System (ADS)

Vaucouleur, Sebastien

2011-02-01

We introduce code query by example for customisation of evolvable software products in general and of enterprise resource planning systems (ERPs) in particular. The concept is based on an initial empirical study on practices around ERP systems. We motivate our design choices based on those empirical results, and we show how the proposed solution helps with respect to the infamous upgrade problem: the conflict between the need for customisation and the need for upgrade of ERP systems. We further show how code query by example can be used as a form of lightweight static analysis, to detect automatically potential defects in large software products. Code query by example as a form of lightweight static analysis is particularly interesting in the context of ERP systems: it is often the case that programmers working in this field are not computer science specialists but more of domain experts. Hence, they require a simple language to express custom rules.

Visual gate for brain-computer interfaces.

PubMed

Dias, N S; Jacinto, L R; Mendes, P M; Correia, J H

2009-01-01

Brain-Computer Interfaces (BCI) based on event related potentials (ERP) have been successfully developed for applications like virtual spellers and navigation systems. This study tests the use of visual stimuli unbalanced in the subject's field of view to simultaneously cue mental imagery tasks (left vs. right hand movement) and detect subject attention. The responses to unbalanced cues were compared with the responses to balanced cues in terms of classification accuracy. Subject specific ERP spatial filters were calculated for optimal group separation. The unbalanced cues appear to enhance early ERPs related to cue visuospatial processing that improved the classification accuracy (as low as 6%) of ERPs in response to left vs. right cues soon (150-200 ms) after the cue presentation. This work suggests that such visual interface may be of interest in BCI applications as a gate mechanism for attention estimation and validation of control decisions.

Visual statistical learning is related to natural language ability in adults: An ERP study.

PubMed

Daltrozzo, Jerome; Emerson, Samantha N; Deocampo, Joanne; Singh, Sonia; Freggens, Marjorie; Branum-Martin, Lee; Conway, Christopher M

2017-03-01

Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities. Copyright © 2017 Elsevier Inc. All rights reserved.

Visual statistical learning is related to natural language ability in adults: An ERP Study

PubMed Central

Daltrozzo, Jerome; Emerson, Samantha N.; Deocampo, Joanne; Singh, Sonia; Freggens, Marjorie; Branum-Martin, Lee; Conway, Christopher M.

2017-01-01

Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities. PMID:28086142

Age Effects in L2 Grammar Processing as Revealed by ERPs and How (Not) to Study Them

PubMed Central

Meulman, Nienke; Wieling, Martijn; Sprenger, Simone A.; Schmid, Monika S.

2015-01-01

In this study we investigate the effect of age of acquisition (AoA) on grammatical processing in second language learners as measured by event-related brain potentials (ERPs). We compare a traditional analysis involving the calculation of averages across a certain time window of the ERP waveform, analyzed with categorical groups (early vs. late), with a generalized additive modeling analysis, which allows us to take into account the full range of variability in both AoA and time. Sixty-six Slavic advanced learners of German listened to German sentences with correct and incorrect use of non-finite verbs and grammatical gender agreement. We show that the ERP signal depends on the AoA of the learner, as well as on the regularity of the structure under investigation. For gender agreement, a gradual change in processing strategies can be shown that varies by AoA, with younger learners showing a P600 and older learners showing a posterior negativity. For verb agreement, all learners show a P600 effect, irrespective of AoA. Based on their behavioral responses in an offline grammaticality judgment task, we argue that the late learners resort to computationally less efficient processing strategies when confronted with (lexically determined) syntactic constructions different from the L1. In addition, this study highlights the insights the explicit focus on the time course of the ERP signal in our analysis framework can offer compared to the traditional analysis. PMID:26683335

Neuromarkers of Post-Traumatic Stress Disorder (PTSD) in a patient after bilateral hand amputation - ERP case study.

PubMed

Chrapusta, Anna; Kropotov, Juri D; Pąchalska, Maria

2017-06-08

Introduction. There is a lack in the worldwide literature of reports on the Neuromarkers of Post-Traumatic Stress Disorder (PTSD) in patients after bilateral hand amputation The aim of this study was to test a hypothesis regarding developing Post-Traumatic Stress Disorder (PTSD) in a patient after bilateral hand amputation with the use of Event Related Potentials (ERPs). On the basis of previous research, the amplitudes of P3 ERP components elicited in the cued GO/NOGO tasks have been chosen as candidates for neuromarkers of PTSD. Case study. A 24-year-old patient had undergone bilateral hand amputation 12 months previously. The patient was repeatedly operated on (he had undergone successful bilateral hand replantation) and despite the severity of the injuries, he recovered. However, the patient complained of flashbacks, anxiety and sleep difficulties. Specialist tests showed the presence of PTSD. The patient participated in the cued GO/NOGO task (Kropotov, 2009) with recording 19-channel EEG. P3 GO and NOGO waves in this task were found to be significantly smaller, in comparison to a group of healthy control subjects of the same age (N=23) taken from the HBI normative database (https://www.hbimed.com/). This observed pattern of ERP waves in the patient corresponds to the pattern found in PTSD patients. Conclusions. ERPs in a GO/NOGO task can be used in the assessment of the functional brain changes induced by chronic PTSD.

The relation between race-related implicit associations and scalp-recorded neural activity evoked by faces from different races.

PubMed

He, Yi; Johnson, Marcia K; Dovidio, John F; McCarthy, Gregory

2009-01-01

The neural correlates of the perception of faces from different races were investigated. White participants performed a gender identification task in which Asian, Black, and White faces were presented while event-related potentials (ERPs) were recorded. Participants also completed an implicit association task for Black (IAT-Black) and Asian (IAT-Asian) faces. ERPs evoked by Black and White faces differed, with Black faces evoking a larger positive ERP that peaked at 168 ms over the frontal scalp, and White faces evoking a larger negative ERP that peaked at 244 ms. These Black/White ERP differences significantly correlated with participants' scores on the IAT-Black. ERPs also differentiated White from Asian faces and a significant correlation was obtained between the White-Asian ERP difference waves at approximately 500 ms and the IAT-Asian. A positive ERP at 116 ms over occipital scalp differentiated all three races, but was not correlated with either IAT. In addition, a late positive component (around 592 ms) was greater for the same race compared to either other race faces, suggesting potentially more extended or deeper processing of the same race faces. Taken together, the ERP/IAT correlations observed for both other races indicate the influence of a race-sensitive evaluative process that may include early more automatic and/or implicit processes and relatively later more controlled processes.

The Relation between Race-related Implicit Associations and Scalp-recorded Neural Activity Evoked by Faces from Different Races

PubMed Central

He, Yi; Johnson, Marcia K.; Dovidio, John F.; McCarthy, Gregory

2009-01-01

The neural correlates of the perception of faces from different races were investigated. White participants performed a gender identification task in which Asian, Black, and White faces were presented while event-related potentials (ERPs) were recorded. Participants also completed an implicit association task for Black (IAT-Black) and Asian (IAT-Asian) faces. ERPs evoked by Black and White faces differed, with Black faces evoking a larger positive ERP that peaked at 168 ms over the frontal scalp, and White faces evoking a larger negative ERP that peaked at 244 ms. These Black/White ERP differences significantly correlated with participants’ scores on the IAT-Black. ERPs also differentiated White from Asian faces and a significant correlation was obtained between the White-Asian ERP difference waves at ~500 ms and the IAT-Asian. A positive ERP at 116 ms over occipital scalp differentiated all three races, but was not correlated with either IAT. In addition, a late positive component (around 592 ms) was greater for the same race compared to either other race faces, suggesting potentially more extended or deeper processing of the same race faces. Taken together, the ERP/IAT correlations observed for both other races indicate the influence of a race-sensitive evaluative process that may include early more automatic and/or implicit processes and relatively later more controlled processes. PMID:19562628

Majority of Enterprise Resource Planning (ERP) Projects Fail--M-DCPS Is a Rare Exception. Information Capsule. Volume 1108

ERIC Educational Resources Information Center

Blazer, Christie

2012-01-01

A high percentage of ERP projects are classified as failures, leaving organizations with only partially functioning systems or, worse yet, with no ERP systems at all. Those that do succeed usually take significantly longer than expected and encounter staggering budget overruns. This Information Capsule summarizes 10 high profile ERP implementation…

Making sense of all the conflict: a theoretical review and critique of conflict-related ERPs.

PubMed

Larson, Michael J; Clayson, Peter E; Clawson, Ann

2014-09-01

Cognitive control theory suggests that goal-directed behavior is governed by a dynamic interplay between areas of the prefrontal cortex. Critical to cognitive control is the detection and resolution of competing stimulus or response representations (i.e., conflict). Event-related potential (ERP) research provides a window into the nature and precise temporal sequence of conflict monitoring. We critically review the research on conflict-related ERPs, including the error-related negativity (ERN), Flanker N2, Stroop N450 and conflict slow potential (conflict SP or negative slow wave [NSW]), and provide an analysis of how these ERPs inform conflict monitoring theory. Overall, there is considerable evidence that amplitude of the ERN is sensitive to the degree of response conflict, consistent with a role in conflict monitoring. It remains unclear, however, to what degree contextual, individual, affective, and motivational factors influence ERN amplitudes and how ERN amplitudes are related to regulative changes in behavior. The Flanker N2, Stroop N450, and conflict SP ERPs represent distinct conflict-monitoring processes that reflect conflict detection (N2, N450) and conflict adjustment or resolution processes (N2, conflict SP). The investigation of conflict adaptation effects (i.e., sequence or sequential trial effects) shows that the N2 and conflict SP reflect post-conflict adjustments in cognitive control, but the N450 generally does not. Conflict-related ERP research provides a promising avenue for understanding the effects of individual differences on cognitive control processes in healthy, neurologic and psychiatric populations. Comparisons between the major conflict-related ERPs and suggestions for future studies to clarify the nature of conflict-related neural processes are provided. Copyright © 2014 Elsevier B.V. All rights reserved.

Propofol and midazolam inhibit conscious memory processes very soon after encoding: an event-related potential study of familiarity and recollection in volunteers.

PubMed

Veselis, Robert A; Pryor, Kane O; Reinsel, Ruth A; Li, Yuelin; Mehta, Meghana; Johnson, Ray

2009-02-01

Intravenous drugs active via gamma-aminobutyric acid receptors to produce memory impairment during conscious sedation. Memory function was assessed using event-related potentials (ERPs) while drug was present. The continuous recognition task measured recognition of photographs from working (6 s) and long-term (27 s) memory while ERPs were recorded from Cz (familiarity recognition) and Pz electrodes (recollection recognition). Volunteer participants received sequential doses of one of placebo (n = 11), 0.45 and 0.9 microg/ml propofol (n = 10), 20 and 40 ng/ml midazolam (n = 12), 1.5 and 3 microg/ml thiopental (n = 11), or 0.25 and 0.4 ng/ml dexmedetomidine (n = 11). End-of-day yes/no recognition 225 min after the end of drug infusion tested memory retention of pictures encoded on the continuous recognition tasks. Active drugs increased reaction times and impaired memory on the continuous recognition task equally, except for a greater effect of midazolam (P < 0.04). Forgetting from continuous recognition tasks to end of day was similar for all drugs (P = 0.40), greater than placebo (P < 0.001). Propofol and midazolam decreased the area between first presentation (new) and recognized (old, 27 s later) ERP waveforms from long-term memory for familiarity (P = 0.03) and possibly for recollection processes (P = 0.12). Propofol shifted ERP amplitudes to smaller voltages (P < 0.002). Dexmedetomidine may have impaired familiarity more than recollection processes (P = 0.10). Thiopental had no effect on ERPs. Propofol and midazolam impaired recognition ERPs from long-term memory but not working memory. ERP measures of memory revealed different pathways to end-of-day memory loss as early as 27 s after encoding.

A hybrid three-class brain-computer interface system utilizing SSSEPs and transient ERPs

NASA Astrophysics Data System (ADS)

Breitwieser, Christian; Pokorny, Christoph; Müller-Putz, Gernot R.

2016-12-01

Objective. This paper investigates the fusion of steady-state somatosensory evoked potentials (SSSEPs) and transient event-related potentials (tERPs), evoked through tactile simulation on the left and right-hand fingertips, in a three-class EEG based hybrid brain-computer interface. It was hypothesized, that fusing the input signals leads to higher classification rates than classifying tERP and SSSEP individually. Approach. Fourteen subjects participated in the studies, consisting of a screening paradigm to determine person dependent resonance-like frequencies and a subsequent online paradigm. The whole setup of the BCI system was based on open interfaces, following suggestions for a common implementation platform. During the online experiment, subjects were instructed to focus their attention on the stimulated fingertips as indicated by a visual cue. The recorded data were classified during runtime using a multi-class shrinkage LDA classifier and the outputs were fused together applying a posterior probability based fusion. Data were further analyzed offline, involving a combined classification of SSSEP and tERP features as a second fusion principle. The final results were tested for statistical significance applying a repeated measures ANOVA. Main results. A significant classification increase was achieved when fusing the results with a combined classification compared to performing an individual classification. Furthermore, the SSSEP classifier was significantly better in detecting a non-control state, whereas the tERP classifier was significantly better in detecting control states. Subjects who had a higher relative band power increase during the screening session also achieved significantly higher classification results than subjects with lower relative band power increase. Significance. It could be shown that utilizing SSSEP and tERP for hBCIs increases the classification accuracy and also that tERP and SSSEP are not classifying control- and non-control states with the same level of accuracy.

Exploring the experience of an enhanced recovery programme for gynaecological cancer patients: a qualitative study.

PubMed

Archer, Stephanie; Montague, Jane; Bali, Anish

2014-04-04

Perioperative enhanced recovery programmes (ERPs), identified as initiatives that improve care and save money, have been adopted by NHS Improvement and are currently being rolled out across many surgical departments within the NHS. To date, five papers have specifically explored patients' experiences of ERPs; none, however, has explored the gynaecological cancer patient experience. In total, 14 women (mean age, 66 years) participated in an audio-recorded face-to-face or telephone interview in which they discussed their experience of taking part in an ERP. The resulting data were transcribed verbatim and analysed using interpretative phenomenological analysis. Two main themes emerged from the analysis. The first, 'Taking part in the programme', highlights two important aspects of the ERP: being given an opportunity to receive information and, following this, to build knowledge about the programme. The theme also explores the challenges associated with the programme, particularly around getting mobile and complying with its demands - the women report experiencing a constant battle between intuition and instruction. The second theme, 'Home', focuses on the role home plays in motivating the patients to aim for an early discharge from hospital. Patients describe their need to return to a suitable home and the need for support from others. They also discuss the importance of the follow-up phone call. Overall, the patients in this study positively assessed the individual aspects of the ERP, in particular, information resources, the availability of the physiotherapist and the delivery of follow-up phone calls. These findings highlight the importance of developing and maintaining individual aspects of ERPs over time, to ensure their sensitivity and responsiveness to patient needs.

Auditory event-related potentials in subcortical vascular cognitive impairment and in Alzheimer's disease.

PubMed

Muscoso, E G; Costanzo, E; Daniele, O; Maugeri, D; Natale, E; Caravaglios, G

2006-11-01

Few studies exist on ERPs and patients with subcortical vascular cognitive impairment (SVCI). This latter is a quite homogeneous subtype of vascular dementia whose cognitive profile is quite different from that of Alzheimer disease (AD). The present study aims at comparing the ERPs profile both in patients with SVCI and in patients with AD. ERPs and psychometric tests were collected from 39 healthy elderly controls, 51 patients with SVCI and 43 patients with AD. Subjects mentally count high pitched target tones that were randomly intermixed with low pitched frequent tones. We measured ERPs latencies (N1, P2, N2 and P3), and interpeak latencies (N1-P3, N1-P2, N1-N2). Grand averaged potentials in SVCI showed a significant increase of P3 latency. AD patients showed a prolongation of N1, P2, N2, P3 latencies. As far as interpeak latencies are concerned, SVCI patients showed a significant prolongation of N1-P3, AD patients had a significant increase of N1-N2, and N1-P3 intervals. When all patients were considered as a single group, correlation of neuropsychological tests scores showed a significant negative relationship between P300 latency and, respectively, Mini Mental Status Examination, auditive and visual span forward. In both groups, ERPs latency sensitivity, was low, whilst specificity values were quite high. Our finding suggest that these two dementing diseases have different electrophysiologic features that may be related to their specific underlying pathogenetic mechanism; in particular, we hypothesise that, differently from AD, P300 latency prolongation characterizes the early stage of SVCI. So, this ERPs approach could be helpful to detect early alterations of the attentional/working-memory functions in patients with subcortical ischaemic vascular disease.

Using kinematic analysis of movement to predict the time occurrence of an evoked potential associated with a motor command.

PubMed

O'Reilly, Christian; Plamondon, Réjean; Landou, Mohamed K; Stemmer, Brigitte

2013-01-01

This article presents an exploratory study investigating the possibility of predicting the time occurrence of a motor event related potential (ERP) from a kinematic analysis of human movements. Although the response-locked motor potential may link the ERP components to the recorded response, to our knowledge no previous attempt has been made to predict a priori (i.e. before any contact with the electroencephalographic data) the time occurrence of an ERP component based only on the modeling of an overt response. The proposed analysis relies on the delta-lognormal modeling of velocity, as proposed by the kinematic theory of rapid human movement used in several studies of motor control. Although some methodological aspects of this technique still need to be fine-tuned, the initial results showed that the model-based kinematic analysis allowed the prediction of the time occurrence of a motor command ERP in most participants in the experiment. The average map of the motor command ERPs showed that this signal was stronger in electrodes close to the contra-lateral motor area (Fz, FCz, FC1, and FC3). These results seem to support the claims made by the kinematic theory that a motor command is emitted at time t(0), the time reference parameter of the model. This article proposes a new time marker directly associated with a cerebral event (i.e. the emission of a motor command) that can be used for the development of new data analysis methodologies and for the elaboration of new experimental protocols based on ERP. © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Accelerating Computation of DCM for ERP in MATLAB by External Function Calls to the GPU.

PubMed

Wang, Wei-Jen; Hsieh, I-Fan; Chen, Chun-Chuan

2013-01-01

This study aims to improve the performance of Dynamic Causal Modelling for Event Related Potentials (DCM for ERP) in MATLAB by using external function calls to a graphics processing unit (GPU). DCM for ERP is an advanced method for studying neuronal effective connectivity. DCM utilizes an iterative procedure, the expectation maximization (EM) algorithm, to find the optimal parameters given a set of observations and the underlying probability model. As the EM algorithm is computationally demanding and the analysis faces possible combinatorial explosion of models to be tested, we propose a parallel computing scheme using the GPU to achieve a fast estimation of DCM for ERP. The computation of DCM for ERP is dynamically partitioned and distributed to threads for parallel processing, according to the DCM model complexity and the hardware constraints. The performance efficiency of this hardware-dependent thread arrangement strategy was evaluated using the synthetic data. The experimental data were used to validate the accuracy of the proposed computing scheme and quantify the time saving in practice. The simulation results show that the proposed scheme can accelerate the computation by a factor of 155 for the parallel part. For experimental data, the speedup factor is about 7 per model on average, depending on the model complexity and the data. This GPU-based implementation of DCM for ERP gives qualitatively the same results as the original MATLAB implementation does at the group level analysis. In conclusion, we believe that the proposed GPU-based implementation is very useful for users as a fast screen tool to select the most likely model and may provide implementation guidance for possible future clinical applications such as online diagnosis.

Accelerating Computation of DCM for ERP in MATLAB by External Function Calls to the GPU

PubMed Central

Wang, Wei-Jen; Hsieh, I-Fan; Chen, Chun-Chuan

2013-01-01

This study aims to improve the performance of Dynamic Causal Modelling for Event Related Potentials (DCM for ERP) in MATLAB by using external function calls to a graphics processing unit (GPU). DCM for ERP is an advanced method for studying neuronal effective connectivity. DCM utilizes an iterative procedure, the expectation maximization (EM) algorithm, to find the optimal parameters given a set of observations and the underlying probability model. As the EM algorithm is computationally demanding and the analysis faces possible combinatorial explosion of models to be tested, we propose a parallel computing scheme using the GPU to achieve a fast estimation of DCM for ERP. The computation of DCM for ERP is dynamically partitioned and distributed to threads for parallel processing, according to the DCM model complexity and the hardware constraints. The performance efficiency of this hardware-dependent thread arrangement strategy was evaluated using the synthetic data. The experimental data were used to validate the accuracy of the proposed computing scheme and quantify the time saving in practice. The simulation results show that the proposed scheme can accelerate the computation by a factor of 155 for the parallel part. For experimental data, the speedup factor is about 7 per model on average, depending on the model complexity and the data. This GPU-based implementation of DCM for ERP gives qualitatively the same results as the original MATLAB implementation does at the group level analysis. In conclusion, we believe that the proposed GPU-based implementation is very useful for users as a fast screen tool to select the most likely model and may provide implementation guidance for possible future clinical applications such as online diagnosis. PMID:23840507

Dissociation between arithmetic relatedness and distance effects is modulated by task properties: an ERP study comparing explicit vs. implicit arithmetic processing.

PubMed

Avancini, Chiara; Galfano, Giovanni; Szűcs, Dénes

2014-12-01

Event-related potential (ERP) studies have detected several characteristic consecutive amplitude modulations in both implicit and explicit mental arithmetic tasks. Implicit tasks typically focused on the arithmetic relatedness effect (in which performance is affected by semantic associations between numbers) while explicit tasks focused on the distance effect (in which performance is affected by the numerical difference of to-be-compared numbers). Both task types elicit morphologically similar ERP waves which were explained in functionally similar terms. However, to date, the relationship between these tasks has not been investigated explicitly and systematically. In order to fill this gap, here we examined whether ERP effects and their underlying cognitive processes in implicit and explicit mental arithmetic tasks differ from each other. The same group of participants performed both an implicit number-matching task (in which arithmetic knowledge is task-irrelevant) and an explicit arithmetic-verification task (in which arithmetic knowledge is task-relevant). 129-channel ERP data differed substantially between tasks. In the number-matching task, the arithmetic relatedness effect appeared as a negativity over left-frontal electrodes whereas the distance effect was more prominent over right centro-parietal electrodes. In the verification task, all probe types elicited similar N2b waves over right fronto-central electrodes and typical centro-parietal N400 effects over central electrodes. The distance effect appeared as an early-rising, long-lasting left parietal negativity. We suggest that ERP effects in the implicit task reflect access to semantic memory networks and to magnitude discrimination, respectively. In contrast, effects of expectation violation are more prominent in explicit tasks and may mask more delicate cognitive processes. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Dissociation between arithmetic relatedness and distance effects is modulated by task properties: An ERP study comparing explicit vs. implicit arithmetic processing

PubMed Central

Avancini, Chiara; Galfano, Giovanni; Szűcs, Dénes

2014-01-01

Event-related potential (ERP) studies have detected several characteristic consecutive amplitude modulations in both implicit and explicit mental arithmetic tasks. Implicit tasks typically focused on the arithmetic relatedness effect (in which performance is affected by semantic associations between numbers) while explicit tasks focused on the distance effect (in which performance is affected by the numerical difference of to-be-compared numbers). Both task types elicit morphologically similar ERP waves which were explained in functionally similar terms. However, to date, the relationship between these tasks has not been investigated explicitly and systematically. In order to fill this gap, here we examined whether ERP effects and their underlying cognitive processes in implicit and explicit mental arithmetic tasks differ from each other. The same group of participants performed both an implicit number-matching task (in which arithmetic knowledge is task-irrelevant) and an explicit arithmetic-verification task (in which arithmetic knowledge is task-relevant). 129-channel ERP data differed substantially between tasks. In the number-matching task, the arithmetic relatedness effect appeared as a negativity over left-frontal electrodes whereas the distance effect was more prominent over right centro-parietal electrodes. In the verification task, all probe types elicited similar N2b waves over right fronto-central electrodes and typical centro-parietal N400 effects over central electrodes. The distance effect appeared as an early-rising, long-lasting left parietal negativity. We suggest that ERP effects in the implicit task reflect access to semantic memory networks and to magnitude discrimination, respectively. In contrast, effects of expectation violation are more prominent in explicit tasks and may mask more delicate cognitive processes. PMID:25450162

Single-trial EEG-informed fMRI reveals spatial dependency of BOLD signal on early and late IC-ERP amplitudes during face recognition.

PubMed

Wirsich, Jonathan; Bénar, Christian; Ranjeva, Jean-Philippe; Descoins, Médéric; Soulier, Elisabeth; Le Troter, Arnaud; Confort-Gouny, Sylviane; Liégeois-Chauvel, Catherine; Guye, Maxime

2014-10-15

Simultaneous EEG-fMRI has opened up new avenues for improving the spatio-temporal resolution of functional brain studies. However, this method usually suffers from poor EEG quality, especially for evoked potentials (ERPs), due to specific artifacts. As such, the use of EEG-informed fMRI analysis in the context of cognitive studies has particularly focused on optimizing narrow ERP time windows of interest, which ignores the rich diverse temporal information of the EEG signal. Here, we propose to use simultaneous EEG-fMRI to investigate the neural cascade occurring during face recognition in 14 healthy volunteers by using the successive ERP peaks recorded during the cognitive part of this process. N170, N400 and P600 peaks, commonly associated with face recognition, were successfully and reproducibly identified for each trial and each subject by using a group independent component analysis (ICA). For the first time we use this group ICA to extract several independent components (IC) corresponding to the sequence of activation and used single-trial peaks as modulation parameters in a general linear model (GLM) of fMRI data. We obtained an occipital-temporal-frontal stream of BOLD signal modulation, in accordance with the three successive IC-ERPs providing an unprecedented spatio-temporal characterization of the whole cognitive process as defined by BOLD signal modulation. By using this approach, the pattern of EEG-informed BOLD modulation provided improved characterization of the network involved than the fMRI-only analysis or the source reconstruction of the three ERPs; the latter techniques showing only two regions in common localized in the occipital lobe. Copyright © 2014 Elsevier Inc. All rights reserved.

The influence of behavioral relevance on the processing of global scene properties: An ERP study.

PubMed

Hansen, Natalie E; Noesen, Birken T; Nador, Jeffrey D; Harel, Assaf

2018-05-02

Recent work studying the temporal dynamics of visual scene processing (Harel et al., 2016) has found that global scene properties (GSPs) modulate the amplitude of early Event-Related Potentials (ERPs). It is still not clear, however, to what extent the processing of these GSPs is influenced by their behavioral relevance, determined by the goals of the observer. To address this question, we investigated how behavioral relevance, operationalized by the task context impacts the electrophysiological responses to GSPs. In a set of two experiments we recorded ERPs while participants viewed images of real-world scenes, varying along two GSPs, naturalness (manmade/natural) and spatial expanse (open/closed). In Experiment 1, very little attention to scene content was required as participants viewed the scenes while performing an orthogonal fixation-cross task. In Experiment 2 participants saw the same scenes but now had to actively categorize them, based either on their naturalness or spatial expense. We found that task context had very little impact on the early ERP responses to the naturalness and spatial expanse of the scenes: P1, N1, and P2 could distinguish between open and closed scenes and between manmade and natural scenes across both experiments. Further, the specific effects of naturalness and spatial expanse on the ERP components were largely unaffected by their relevance for the task. A task effect was found at the N1 and P2 level, but this effect was manifest across all scene dimensions, indicating a general effect rather than an interaction between task context and GSPs. Together, these findings suggest that the extraction of global scene information reflected in the early ERP components is rapid and very little influenced by top-down observer-based goals. Copyright © 2018 Elsevier Ltd. All rights reserved.

The ERP research about the influence of the music of Chopin on working memory

NASA Astrophysics Data System (ADS)

Sun, C. A.; Wei, Hong-tao; Yue, Li-juan

2011-10-01

This study is to examine the effect of the music of Chopin on working memory and the electrical activity of the brain in different conditions by using event-related potentials (ERPs), adopting n-back experimental paradigm and to study the neuromechanism. Thirty adults performed behavioral experiments with three conditions of music and two levels of n-back task. Fourteen normal adults performed ERP experiments with the same program as the behavioral experiment and the EEG were recorded. Chopin music improved people's working memory and pilot music improved most effectively.P3 peak amplitude decreased as working memory load increased. Especially in high load task, P3 peak amplitude decreased gradually in pilot music, background music and free music condition.

Feasibility of event-related potential (ERP) biomarker use to study effects of mother's voice exposure on speech sound differentiation of preterm infants.

PubMed

D Chorna, Olena; L Hamm, Ellyn; Shrivastava, Hemang; Maitre, Nathalie L

2018-01-01

Atypical maturation of auditory neural processing contributes to preterm-born infants' language delays. Event-related potential (ERP) measurement of speech-sound differentiation might fill a gap in treatment-response biomarkers to auditory interventions. We evaluated whether these markers could measure treatment effects in a quasi-randomized prospective study. Hospitalized preterm infants in passive or active, suck-contingent mother's voice exposure groups were not different at baseline. Post-intervention, the active group had greater increases in/du/-/gu/differentiation in left frontal and temporal regions. Infants with brain injury had lower baseline/ba/-/ga/and/du/-/gu/differentiation than those without. ERP provides valid discriminative, responsive, and predictive biomarkers of infant speech-sound differentiation.

Brain responses to filled gaps.

PubMed

Hestvik, Arild; Maxfield, Nathan; Schwartz, Richard G; Shafer, Valerie

2007-03-01

An unresolved issue in the study of sentence comprehension is whether the process of gap-filling is mediated by the construction of empty categories (traces), or whether the parser relates fillers directly to the associated verb's argument structure. We conducted an event-related potentials (ERP) study that used the violation paradigm to examine the time course and spatial distribution of brain responses to ungrammatically filled gaps. The results indicate that the earliest brain response to the violation is an early left anterior negativity (eLAN). This ERP indexes an early phase of pure syntactic structure building, temporally preceding ERPs that reflect semantic integration and argument structure satisfaction. The finding is interpreted as evidence that gap-filling is mediated by structurally predicted empty categories, rather than directly by argument structure operations.

Clinch River - Environmental Restoration Program (CR-ERP) study, ambient water toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russell, C.L.

1997-06-01

Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of July 22-29, 1993, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Surface water samples were collected by TVA Field Engineering personnel from Clinch River Mile 19.0 and Mile 22.0 on July 21, 23, and 26. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival, growth,more » or reproduction) to either species in testing conducted by TVA.« less

Differences in early and late stages of information processing between slow versus fast participants.

PubMed

Portella, Claudio; Machado, Sergio; Paes, Flávia; Cagy, Mauricio; Sack, Alexander T; Sandoval-Carrillo, Ada; Salas-Pacheco, Jose; Silva, Adriana Cardoso; Piedade, Roberto; Ribeiro, Pedro; Nardi, Antonio Egídio; Arias-Carrión, Oscar

2014-01-01

The human brain is a system consisting of various interconnected neural networks, with functional specialization coexisting with functional integration occurring both; temporally and spatially at many levels. The current study ranked and compared fast and slow participants in processing information by assessing latency and amplitude of early and late Event-Related Potential (ERP) components, including P200, N200, Premotor Potential (PMP) and P300. In addition, the Reaction Time (RT) of participants was compared and related to the respective ERP components. For this purpose, twenty right-handed and healthy individuals were subjected to a classical ERP "Oddball" paradigm. Principal Component Analysis (PCA) and Discriminant Function analyses (DFA) used PRE components and the Reaction Time (RT) to classify individuals. Our results indicate that latencies of P200 (O2 electrode), N200 (O2), PMP (C3) and P300 (Pz) components are significantly reduced in the group of fast responding participants. In addition, the P200 amplitude is significantly increased in the group of fast responding participants. Based on these findings, we suggest that the ERP is able to detect even minimal impairments, in the processing of somatosensory information and cognitive and motor stages. Hence, the study of ERP might also be capable of assessing sensorimotor dysfunctions in healthy old-aged people and in neuropsychiatric patients (suffering from dementia, Parkinson's disease, and other neurological disorders).

Cued uncertainty modulates later recognition of emotional pictures: An ERP study.

PubMed

Lin, Huiyan; Xiang, Jing; Li, Saili; Liang, Jiafeng; Zhao, Dongmei; Yin, Desheng; Jin, Hua

2017-06-01

Previous studies have shown that uncertainty about the emotional content of an upcoming event modulates event-related potentials (ERPs) during the encoding of the event, and this modulation is affected by whether there are cues (i.e., cued uncertainty) or not (i.e., uncued uncertainty) prior to the encoding of the uncertain event. Recently, we showed that uncued uncertainty affected ERPs in later recognition of the emotional event. However, it is as yet unknown how the ERP effects of recognition are modulated by cued uncertainty. To address this issue, participants were asked to view emotional (negative and neutral) pictures that were presented after cues. The cues either indicated the emotional content of the pictures (the certain condition) or not (the cued uncertain condition). Subsequently, participants had to perform an unexpected old/new task in which old and novel pictures were shown without any cues. ERP data in the old/new task showed smaller P2 amplitudes for neutral pictures in the cued uncertain condition compared to the certain condition, but this uncertainty effect was not observed for negative pictures. Additionally, P3 amplitudes were generally enlarged for pictures in the cued uncertain condition. Taken together, the present findings indicate that cued uncertainty alters later recognition of emotional events in relevance to feature processing and attention allocation. Copyright © 2017. Published by Elsevier B.V.

Earthquake experience interference effects in a modified Stroop task: an ERP study.

PubMed

Wei, Dongtao; Qiu, Jiang; Tu, Shen; Tian, Fang; Su, Yanhua; Luo, Yuejia

2010-05-03

The effects of the modified Stroop task on ERP were investigated in 20 subjects who had experienced the Sichuan earthquake and a matched control group. ERP data showed that Incongruent stimuli elicited a more negative ERP deflection (N300-450) than did Congruent stimuli between 300 and 450 ms post-stimulus in the earthquake group but not found in the control group, and the N300-450 might reflect conflict monitor (the information of color and meaning do not match) in the early phase of perception identification due to their sensitivity to the external stimulus. Then, Incongruent stimuli elicited a more negative ERP deflection than did Congruent stimuli between 450 and 650 ms post-stimulus in both the groups. Dipole source analysis showed that the N450-650 was mainly generated in the ACC contributed to this effect in the control group, which might be related to monitor and conflict resolution. However, in the earthquake group, the N450-650 was generated in the thalamus, which might be involved in inhibiting and compensating of the ACC which may be related to conflict resolution process. 2010 Elsevier Ireland Ltd. All rights reserved.

Online processing of moral transgressions: ERP evidence for spontaneous evaluation

PubMed Central

Kunkel, Angelika; Mackenzie, Ian G.; Filik, Ruth

2015-01-01

Experimental studies using fictional moral dilemmas indicate that both automatic emotional processes and controlled cognitive processes contribute to moral judgments. However, not much is known about how people process socio-normative violations that are more common to their everyday life nor the time-course of these processes. Thus, we recorded participants’ electrical brain activity while they were reading vignettes that either contained morally acceptable vs unacceptable information or text materials that contained information which was either consistent or inconsistent with their general world knowledge. A first event-related brain potential (ERP) positivity peaking at ∼200 ms after critical word onset (P200) was larger when this word involved a socio-normative or knowledge-based violation. Subsequently, knowledge-inconsistent words triggered a larger centroparietal ERP negativity at ∼320 ms (N400), indicating an influence on meaning construction. In contrast, a larger ERP positivity (larger late positivity), which also started at ∼320 ms after critical word onset, was elicited by morally unacceptable compared with acceptable words. We take this ERP positivity to reflect an implicit evaluative (good–bad) categorization process that is engaged during the online processing of moral transgressions. PMID:25556210

Overview of external reference pricing systems in Europe

PubMed Central

Rémuzat, Cécile; Urbinati, Duccio; Mzoughi, Olfa; El Hammi, Emna; Belgaied, Wael; Toumi, Mondher

2015-01-01

Background and objectives External reference pricing (ERP) is a price regulation tool widely used by policy makers in the European Union (EU) Member States (MS) to contain drug cost, although in theory, it may contribute to modulate prices up and down. The objective of this article was to summarise and discuss the main findings of part of a large project conducted for the European Commission (‘External reference pricing of medicinal products: simulation-based considerations for cross-country coordination’; see www.ec.europa.eu/health/healthcare/docs/erp_reimbursement_medicinal_products_en.pdf) that aimed to provide an overview of ERP systems, both on processes and potential issues in 31 European countries (28 EU MS, Iceland, Norway, and Switzerland). Methods A systematic structured literature review was conducted to identify and characterise the use of ERP in the selected countries, to describe its impact on the prices of pharmaceuticals, and to discuss the possible cross-country coordination issues in EU MS. This research was complemented with a consultation of competent authorities’ and international organisations’ representatives to address the main issues or uncertainties identified through the literature review. Results All selected countries applied ERP, except the United Kingdom and Sweden. Twenty-three countries used ERP as the main systematic criterion for pricing. In the majority of European countries, ERP was based on legislated pricing rules with different levels of accuracy. ERP was applied either for all marketed drugs or for specific categories of medicines; it was mainly used for publicly reimbursed medicines. The number of reference countries included in the basket varied from 1 to 31. There was a great variation in the calculation methods used to compute the price; 15 countries used the average price, 7 countries used the lowest price, and 7 countries used other calculation methods. Reported limitations of ERP application included the lack of reliable sources of price information, price heterogeneity, exchange rate volatility, and hidden discounts. Spill-over effect and downward price convergence have often been mentioned as ERP's consequences leading to pricing strategies from pharmaceutical companies. Conclusion While ERP is widely used in Europe, processes and availability of price information vary from one country to another, thus limiting ERP implementation. Furthermore, ERP spill-over effect is a major concern of pharmaceutical firms leading to implementation of the so-called ‘launch sequence strategies’. PMID:27123181

Overview of external reference pricing systems in Europe.

PubMed

Rémuzat, Cécile; Urbinati, Duccio; Mzoughi, Olfa; El Hammi, Emna; Belgaied, Wael; Toumi, Mondher

2015-01-01

External reference pricing (ERP) is a price regulation tool widely used by policy makers in the European Union (EU) Member States (MS) to contain drug cost, although in theory, it may contribute to modulate prices up and down. The objective of this article was to summarise and discuss the main findings of part of a large project conducted for the European Commission ('External reference pricing of medicinal products: simulation-based considerations for cross-country coordination'; see www.ec.europa.eu/health/healthcare/docs/erp_reimbursement_medicinal_products_en.pdf) that aimed to provide an overview of ERP systems, both on processes and potential issues in 31 European countries (28 EU MS, Iceland, Norway, and Switzerland). A systematic structured literature review was conducted to identify and characterise the use of ERP in the selected countries, to describe its impact on the prices of pharmaceuticals, and to discuss the possible cross-country coordination issues in EU MS. This research was complemented with a consultation of competent authorities' and international organisations' representatives to address the main issues or uncertainties identified through the literature review. All selected countries applied ERP, except the United Kingdom and Sweden. Twenty-three countries used ERP as the main systematic criterion for pricing. In the majority of European countries, ERP was based on legislated pricing rules with different levels of accuracy. ERP was applied either for all marketed drugs or for specific categories of medicines; it was mainly used for publicly reimbursed medicines. The number of reference countries included in the basket varied from 1 to 31. There was a great variation in the calculation methods used to compute the price; 15 countries used the average price, 7 countries used the lowest price, and 7 countries used other calculation methods. Reported limitations of ERP application included the lack of reliable sources of price information, price heterogeneity, exchange rate volatility, and hidden discounts. Spill-over effect and downward price convergence have often been mentioned as ERP's consequences leading to pricing strategies from pharmaceutical companies. While ERP is widely used in Europe, processes and availability of price information vary from one country to another, thus limiting ERP implementation. Furthermore, ERP spill-over effect is a major concern of pharmaceutical firms leading to implementation of the so-called 'launch sequence strategies'.

Higher Education ERP: Lessons Learned.

ERIC Educational Resources Information Center

Swartz, Dave; Orgill, Ken

2001-01-01

Shares experiences and lessons learned by chief information officers of large universities about enterprise resource planning (ERP). Specifically, provides a framework for approaching an ERP that could save universities millions of dollars. (EV)

47 CFR 73.207 - Minimum distance separation between stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... kW ERP and 100 meters antenna HAAT (or equivalent lower ERP and higher antenna HAAT based on a class... which have been notified internationally as Class A are limited to a maximum of 3.0 kW ERP at 100 meters... internationally as Class AA are limited to a maximum of 6.0 kW ERP at 100 meters HAAT, or the equivalent; (iii) U...

47 CFR 73.215 - Contour protection for short-spaced assignments.

Code of Federal Regulations, 2010 CFR

2010-10-01

... station pursuant to 47 CFR 73.211(b)(3): 6 kW ERP/240 meters HAAT—Class A 25 kW ERP/150 meters HAAT—Class B1 50 kW ERP/472 meters HAAT—Class B (b) Applicants requesting short-spaced assignments pursuant to... achieved: (1) The ERP and antenna HAAT of the proposed station in the direction of the contours of other...

47 CFR 73.215 - Contour protection for short-spaced assignments.

Code of Federal Regulations, 2011 CFR

2011-10-01

... station pursuant to 47 CFR 73.211(b)(3): 6 kW ERP/240 meters HAAT—Class A 25 kW ERP/150 meters HAAT—Class B1 50 kW ERP/472 meters HAAT—Class B (b) Applicants requesting short-spaced assignments pursuant to... achieved: (1) The ERP and antenna HAAT of the proposed station in the direction of the contours of other...

An Uncontrolled Examination of a 5-Day Intensive Treatment for Pediatric OCD

ERIC Educational Resources Information Center

Whiteside, Stephen P.; Jacobsen, Amy Brown

2010-01-01

This study examined the feasibility of a 5-day intensive treatment for pediatric obsessive-compulsive disorder (OCD). Fifteen children with OCD received a week-long treatment based on exposure and response prevention (ERP). The intervention also emphasized teaching children and parents how to conduct ERP independently at home. All families…

Examining Success Factors Related to ERP Implementations in Higher Education Shared Services Projects

ERIC Educational Resources Information Center

Stoyanoff, Dawn Galadriel Pfeiffer

2012-01-01

This study examined the enterprise resource planning (ERP) implementations that utilized a shared services model in higher education. The purpose of this research was to examine the critical success factors which were perceived to contribute to project success. This research employed a quantitative non-experimental correlational design and the…

Brain Event-Related Potential Correlates of Concept Learning.

ERIC Educational Resources Information Center

Federico, Pat-Anthony

An irrelevant auditory probe procedure was used to evoke brain event-related potentials (ERPs) in 56 Navy recruits while they learned pulsed radar concepts presented to them in study booklets. A mastery test was administered to assess concept acquisition. The research issue was whether brain ERPs recorded while students are in the process of…

ERPs Associated with Monitoring and Evaluation of Monetary Reward and Punishment in Children with ADHD

ERIC Educational Resources Information Center

van Meel, Catharina S.; Heslenfeld, Dirk J.; Oosterlaan, Jaap; Luman, Marjolein; Sergeant, Joseph A.

2011-01-01

Background: Several models of attention-deficit hyperactivity disorder (ADHD) propose abnormalities in the response to behavioural contingencies. Using event-related potentials (ERPs), the present study investigated the monitoring and subsequent evaluation of performance feedback resulting in either reward or punishment in children with ADHD (N =…

ERP correlates of mental arithmetic in preadolescents: influence of ability and effects of morning nutrition

USDA-ARS?s Scientific Manuscript database

The effects of morning nutritional status on ERP correlates of mental arithmetic were studied in preadolescents differing in experience (age) and mathematical skills. Children [right-handed; IQ > 80), randomly assigned to treatment [eat (B) or skip (SB) breakfast (each, n = 41)], were sub-grouped by...

Are Pumpkins Better than Heaven? An ERP Investigation of Order Effects in the Concrete-Word Advantage

ERIC Educational Resources Information Center

Tolentino, Leida C.; Tokowicz, Natasha

2009-01-01

The present study investigated the cognitive and neural mechanisms underlying the processing of concrete and abstract words by recording event-related potentials (ERPs) while participants performed an English lexical decision task. Concrete and abstract words were presented in three stimulus-order conditions: abstract before concrete, concrete…

An ERP Investigation of Regional and Foreign Accent Processing

ERIC Educational Resources Information Center

Goslin, Jeremy; Duffy, Hester; Floccia, Caroline

2012-01-01

This study used event-related potentials (ERPs) to examine whether we employ the same normalisation mechanisms when processing words spoken with a regional accent or foreign accent. Our results showed that the Phonological Mapping Negativity (PMN) following the onset of the final word of sentences spoken with an unfamiliar regional accent was…

Familiarity or Conceptual Priming: Event-Related Potentials in Name Recognition

ERIC Educational Resources Information Center

Stenberg, Georg; Hellman, Johan; Johansson, Mikael; Rosen, Ingmar

2009-01-01

Recent interest has been drawn to the separate components of recognition memory, as studied by event-related potentials (ERPs). In ERPs, recollection is usually accompanied by a late, parietal positive deflection. An earlier, frontal component has been suggested to be a counterpart, accompanying recognition by familiarity. However, this component,…

Neural Indices of Semantic Processing in Early Childhood Distinguish Eventual Stuttering Persistence and Recovery

ERIC Educational Resources Information Center

Kreidler, Kathryn; Wray, Amanda Hampton; Usler, Evan; Weber, Christine

2017-01-01

Purpose: Maturation of neural processes for language may lag in some children who stutter (CWS), and event-related potentials (ERPs) distinguish CWS who have recovered from those who have persisted. The current study explores whether ERPs indexing semantic processing may distinguish children who will eventually persist in stuttering…

Auditory and Speech Processing and Reading Development in Chinese School Children: Behavioural and ERP Evidence

ERIC Educational Resources Information Center

Meng, Xiangzhi; Sai, Xiaoguang; Wang, Cixin; Wang, Jue; Sha, Shuying; Zhou, Xiaolin

2005-01-01

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…

75 FR 10253 - Environmental Impact Statements and Regulations; Availability of EPA Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-05

... concerns about storage, transportation and disposal of hazardous waste and radioactive wastes. EPA... wastes will need to be addressed as the project progresses. Rating EC2. EIS No. 20090378, ERP No. D-COE.... EIS No. 20100008, ERP No. D-GSA-F65079-00, International Falls Land Port of Entry Improvements Study...

From episodic to habitual prospective memory: ERP-evidence for a linear transition

PubMed Central

Meier, Beat; Matter, Sibylle; Baumann, Brigitta; Walter, Stefan; Koenig, Thomas

2014-01-01

Performing a prospective memory task repeatedly changes the nature of the task from episodic to habitual. The goal of the present study was to investigate the neural basis of this transition. In two experiments, we contrasted event-related potentials (ERPs) evoked by correct responses to prospective memory targets in the first, more episodic part of the experiment with those of the second, more habitual part of the experiment. Specifically, we tested whether the early, middle, or late ERP-components, which are thought to reflect cue detection, retrieval of the intention, and post-retrieval processes, respectively, would be changed by routinely performing the prospective memory task. The results showed a differential ERP effect in the middle time window (450–650 ms post-stimulus). Source localization using low resolution brain electromagnetic tomography analysis suggests that the transition was accompanied by an increase of activation in the posterior parietal and occipital cortex. These findings indicate that habitual prospective memory involves retrieval processes guided more strongly by parietal brain structures. In brief, the study demonstrates that episodic and habitual prospective memory tasks recruit different brain areas. PMID:25071519

Cardiovascular fitness and executive control during task-switching: an ERP study.

PubMed

Scisco, Jenna L; Leynes, P Andrew; Kang, Jie

2008-07-01

Cardiovascular fitness recently has been linked to executive control function in older adults. The present study examined the relationship between cardiovascular fitness and executive control in young adults using event-related potentials (ERPs). Participants completed a two-part experiment. In part one, a graded exercise test (GXT) was administered using a cycle ergometer to obtain VO(2)max, a measure of maximal oxygen uptake. High-fit participants had VO(2)max measures at or above the 70th percentile based on age and sex, and low-fit participants had VO(2)max measures at or below the 30th percentile. In part two, a task-switching paradigm was used to investigate executive control. Task-switching trials produced slower response times and greater amplitude for both the P3a and P3b components of the ERP relative to a non-switch trial block. No ERP components varied as a function of fitness group. These findings, combined with results from previous research, suggest that the relationship between greater cardiovascular fitness and better cognitive function emerges after early adulthood.

Endophytic fungi from pigeon pea [Cajanus cajan (L.) Millsp.] produce antioxidant Cajaninstilbene acid.

PubMed

Zhao, JinTong; Fu, YuJie; Luo, Meng; Zu, YuanGang; Wang, Wei; Zhao, ChunJian; Gu, ChengBo

2012-05-02

In this study, novel endophytic fungi producing cajaninstilbene acid (CSA) from pigeon pea [ Cajanus cajan (L.) Millsp.] were investigated and screened. CSA has prominent pharmacological activities. A total of 110 endophytic fungi isolates were grouped into 8 genera on the basis of morphological characteristics, and CSA-producing fungi were screened by liquid chromatography-tandem mass spectrometry (LC-MS/MS). According to ITS-rDNA sequences analysis, the CSA-producing fungi were identified as Fusarium solani (ERP-07), Fusarium oxysporum (ERP-10), and Fusarium proliferatum (ERP-13), respectively. The amount of CSA produced by the ERP-13 reached 504.8 ± 20.1 μg/L or 100.5 ± 9.4 μg/g dry weight of mycelium. In a DPPH radical-scavenging assay, when the concentration of fungal CSA was 500 μg/mL, inhibition percentage could reach 80%, which was almost the same as that of standard CSA. This study first reported the natural antioxidant CSA from endophytic fungi F. solani and F. proliferatum isolated from pigeon pea.

Behavioural and electrophysiological effects related to semantic violations during braille reading.

PubMed

Glyn, Vania; Lim, Vanessa K; Hamm, Jeff P; Mathur, Ashwin; Hughes, Barry

2015-10-01

This study investigated the potential to detect event related potentials (ERPs) occurring in response to a specific task in braille reading. This would expand current methodologies for studying the cognitive processes underlying braille reading. An N400 effect paradigm was utilised, whereby proficient blind braille readers read congruent- and incongruent-ending braille sentences. Kinematic and electroencephalography (EEG) data were obtained simultaneously and synchronised. The ERPs differed between the incongruent and congruent sentences in a manner consistent with the N400 effect found with a previous sighted reading paradigm, demonstrating that ERPs can be obtained during braille reading. The frequency of finger reversals and the degree of intermittency in the finger velocity were significantly higher when reading incongruent versus congruent sentence endings. Both reversals and the potential N400 effect may reflect processes involved in semantic unification. These findings have significant implications for the modelling of braille reading. The refinement of the technique will enable other ERPs to be identified and related to behavioural responses, to further our understanding of the braille reading process. Copyright © 2015 Elsevier Ltd. All rights reserved.

Expression of protein disulfide isomerase family members correlates with tumor progression and patient survival in ovarian cancer

PubMed Central

Samanta, Soma; Tamura, Shuzo; Dubeau, Louis; Mhawech-Fauceglia, Paulette; Miyagi, Yohei; Kato, Hisamori; Lieberman, Rich; Buckanovich, Ronald J.; Lin, Yvonne G.; Neamati, Nouri

2017-01-01

Objective Protein disulfide isomerase (PDI) is an oxidoreductase that is overexpressed in several cancers. PDI family members (PDIs) play a role in various diseases including cancer. Select PDIs were reported as useful markers in other cancers but their expression in ovarian cancer has not been thoroughly assessed. We sought to evaluate the expression of PDI, PDIA6, PDIR, ERp57, ERp72 and AGR3 in ovarian cancer patient samples and examine their prognostic significance. Methods TMA samples from 415 tissues collected from three cancer centers (UM, USC, and KCCRI) were used to assess the expression levels of PDI family proteins using IHC. Results We observed significant increases in PDI (p = 9.16E-36), PDIA6 (p = 5.51E-33), PDIR (p = 1.81E-12), ERp57 (p = 9.13E-07), ERp72 (p = 3.65E-22), and AGR3 (p = 4.56E-24) expression in ovarian cancers compared to normal tissues. Expression of PDI family members also increases during disease progression (p <0.001). All PDI family members are overexpressed in serous ovarian cancer (p<0.001). However, PDI, PDIA6, PDIR, ERp72 and AGR3 are more significantly overexpressed (p<0.001) than ERp57 (p<0.05) in clear cell ovarian carcinoma. Importantly, overexpression of PDI family members is associated with poor survival in ovarian cancer (p = 0.045 for PDI, p = 0.047 for PDIR, p = 0.037 for ERp57, p = 0.046 for ERp72, p = 0.040 for AGR3) with the exception of PDIA6 (p = 0.381). Conclusions Our findings demonstrate that select PDI family members (PDI, PDIR, ERp72, ERp57 and AGR3) are potential prognostic markers for ovarian cancer. PMID:29262583

47 CFR 22.867 - Effective radiated power limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Effective radiated power limits. The effective radiated power (ERP) of ground and airborne stations... peak ERP of airborne mobile station transmitters must not exceed 12 Watts. (b) The peak ERP of ground...

Assessing the Impact of Earth Radiation Pressure Acceleration on Low-Earth Orbit Satellites

NASA Astrophysics Data System (ADS)

Vielberg, Kristin; Forootan, Ehsan; Lück, Christina; Kusche, Jürgen; Börger, Klaus

2017-04-01

The orbits of satellites are influenced by several external forces. The main non-gravitational forces besides thermospheric drag, acting on the surface of satellites, are accelerations due to the Earth and Solar Radiation Pres- sure (SRP and ERP, respectively). The sun radiates visible and infrared light reaching the satellite directly, which causes the SRP. Earth also emits and reflects the sunlight back into space, where it acts on satellites. This is known as ERP acceleration. The influence of ERP increases with decreasing distance to the Earth, and for low-earth orbit (LEO) satellites ERP must be taken into account in orbit and gravity computations. Estimating acceler- ations requires knowledge about energy emitted from the Earth, which can be derived from satellite remote sensing data, and also by considering the shape and surface material of a satellite. In this sensitivity study, we assess ERP accelerations based on different input albedo and emission fields and their modelling for the satellite missions Challenging Mini-Satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE). As input fields, monthly 1°x1° products of Clouds and the Earth's Radiant En- ergy System (CERES), L3 are considered. Albedo and emission models are generated as latitude-dependent, as well as in terms of spherical harmonics. The impact of different albedo and emission models as well as the macro model and the altitude of satellites on ERP accelerations will be discussed.

Implementing enhanced recovery pathways: a literature review with realist synthesis.

PubMed

Coxon, Astrid; Nielsen, Karina; Cross, Jane; Fox, Chris

2017-10-01

Enhanced Recovery Pathways (ERPs) are an increasingly popular, evidenced-based approach to surgery, designed to improve patient outcomes and reduce costs. Despite evidence demonstrating the benefits of these pathways, implementation and adherence have been inconsistent. Using realist synthesis, this review explored the current literature surrounding the implementation of ERPs in the UK. Knowledge consolidation between authors and consulting with field experts helped to guide the search strategy. Relevant medical and social science databases were searched from 2000 to 2016, as well as a general web search. A total of 17 papers were identified, including original research, reviews, case studies and guideline documents. Full texts were analysed, cross-examined, and data extracted and synthesised. Several implementation strategies were identified, including the contexts in which these operated, the subsequent mechanisms of action that were triggered, and the outcome patterns they produced. Context-Mechanism-Outcome (CMO) configurations were generated, tested, and refined. These were grouped to develop two programme theories concerning ERP implementation, one related to the strategy of consulting with staff, the other with appointing a change agent to coordinate and drive the implementation process. These theories highlight instances in which implementation could be improved. Current literature in ERP research is primarily focussed on measuring patient outcomes and cost effectiveness, and as a result, important detail regarding the implementation process is often not reported or described robustly. This review not only provides recommendations for future improvements in ERP implementation, but also highlights specific areas of focus for furthering ERP implementation research.

Simultaneous ERP and fMRI of the auditory cortex in a passive oddball paradigm.

PubMed

Liebenthal, Einat; Ellingson, Michael L; Spanaki, Marianna V; Prieto, Thomas E; Ropella, Kristina M; Binder, Jeffrey R

2003-08-01

Infrequent occurrences of a deviant sound within a sequence of repetitive standard sounds elicit the automatic mismatch negativity (MMN) event-related potential (ERP). The main MMN generators are located in the superior temporal cortex, but their number, precise location, and temporal sequence of activation remain unclear. In this study, ERP and functional magnetic resonance imaging (fMRI) data were obtained simultaneously during a passive frequency oddball paradigm. There were three conditions, a STANDARD, a SMALL deviant, and a LARGE deviant. A clustered image acquisition technique was applied to prevent contamination of the fMRI data by the acoustic noise of the scanner and to limit contamination of the electroencephalogram (EEG) by the gradient-switching artifact. The ERP data were used to identify areas in which the blood oxygenation (BOLD) signal varied with the magnitude of the negativity in each condition. A significant ERP MMN was obtained, with larger peaks to LARGE deviants and with frontocentral scalp distribution, consistent with the MMN reported outside the magnetic field. This result validates the experimental procedures for simultaneous ERP/fMRI of the auditory cortex. Main foci of increased BOLD signal were observed in the right superior temporal gyrus [STG; Brodmann area (BA) 22] and right superior temporal plane (STP; BA 41 and 42). The imaging results provide new information supporting the idea that generators in the right lateral aspect of the STG are implicated in processes of frequency deviant detection, in addition to generators in the right and left STP.

Selective attention to sound location or pitch studied with event-related brain potentials and magnetic fields.

PubMed

Degerman, Alexander; Rinne, Teemu; Särkkä, Anna-Kaisa; Salmi, Juha; Alho, Kimmo

2008-06-01

Event-related brain potentials (ERPs) and magnetic fields (ERFs) were used to compare brain activity associated with selective attention to sound location or pitch in humans. Sixteen healthy adults participated in the ERP experiment, and 11 adults in the ERF experiment. In different conditions, the participants focused their attention on a designated sound location or pitch, or pictures presented on a screen, in order to detect target sounds or pictures among the attended stimuli. In the Attend Location condition, the location of sounds varied randomly (left or right), while their pitch (high or low) was kept constant. In the Attend Pitch condition, sounds of varying pitch (high or low) were presented at a constant location (left or right). Consistent with previous ERP results, selective attention to either sound feature produced a negative difference (Nd) between ERPs to attended and unattended sounds. In addition, ERPs showed a more posterior scalp distribution for the location-related Nd than for the pitch-related Nd, suggesting partially different generators for these Nds. The ERF source analyses found no source distribution differences between the pitch-related Ndm (the magnetic counterpart of the Nd) and location-related Ndm in the superior temporal cortex (STC), where the main sources of the Ndm effects are thought to be located. Thus, the ERP scalp distribution differences between the location-related and pitch-related Nd effects may have been caused by activity of areas outside the STC, perhaps in the inferior parietal regions.

A Mode of Combined ERP and KMS Knowledge Management System Construction

NASA Astrophysics Data System (ADS)

Yuena, Kang; Yangeng, Wen; Qun, Zhou

The core of ERP and knowledge management is quite similar; both will send appropriate knowledge (goods, funds) to the right people (position) at the right time. It is reasonable to believe that increase the knowledge management system in ERP will help companies achieve their goals better. This paper compares the concept of logical point of hall three-dimensional structure of the knowledge management system and the ERP in methodology level. And found they are very similar in the time dimension, logic dimension and knowledge dimension. This laid the basis of methodology in the simultaneous planning, implementation and applications. And then proposed a knowledge-based ERP Multi-Agent Management System Model. Finally, the paper described the process from planning to implementation of knowledge management ERP system with multi-Agent interaction and impact from three concepts, management thinking, software and system.

Interactions between pre-processing and classification methods for event-related-potential classification: best-practice guidelines for brain-computer interfacing.

PubMed

Farquhar, J; Hill, N J

2013-04-01

Detecting event related potentials (ERPs) from single trials is critical to the operation of many stimulus-driven brain computer interface (BCI) systems. The low strength of the ERP signal compared to the noise (due to artifacts and BCI irrelevant brain processes) makes this a challenging signal detection problem. Previous work has tended to focus on how best to detect a single ERP type (such as the visual oddball response). However, the underlying ERP detection problem is essentially the same regardless of stimulus modality (e.g., visual or tactile), ERP component (e.g., P300 oddball response, or the error-potential), measurement system or electrode layout. To investigate whether a single ERP detection method might work for a wider range of ERP BCIs we compare detection performance over a large corpus of more than 50 ERP BCI datasets whilst systematically varying the electrode montage, spectral filter, spatial filter and classifier training methods. We identify an interesting interaction between spatial whitening and regularised classification which made detection performance independent of the choice of spectral filter low-pass frequency. Our results show that pipeline consisting of spectral filtering, spatial whitening, and regularised classification gives near maximal performance in all cases. Importantly, this pipeline is simple to implement and completely automatic with no expert feature selection or parameter tuning required. Thus, we recommend this combination as a "best-practice" method for ERP detection problems.

Aligning ERP systems with companies' real needs: an `Operational Model Based' method

NASA Astrophysics Data System (ADS)

Mamoghli, Sarra; Goepp, Virginie; Botta-Genoulaz, Valérie

2017-02-01

Enterprise Resource Planning (ERP) systems offer standard functionalities that have to be configured and customised by a specific company depending on its own requirements. A consistent alignment is therefore an essential success factor of ERP projects. To manage this alignment, an 'Operational Model Based' method is proposed. It is based on the design and the matching of models, and conforms to the modelling views and constructs of the ISO 19439 and 19440 enterprise-modelling standards. It is characterised by: (1) a predefined design and matching order of the models; (2) the formalisation, in terms of modelling constructs, of alignment and misalignment situations; and (3) their association with a set of decisions in order to mitigate the misalignment risk. Thus, a comprehensive understanding of the alignment management during ERP projects is given. Unlike existing methods, this one includes decisions related to the organisational changes an ERP system can induce, as well as criteria on which the best decision can be based. In this way, it provides effective support and guidance to companies implementing ERP systems, as the alignment process is detailed and structured. The method is applied on the ERP project of a Small and Medium Enterprise, showing that it can be used even in contexts where the ERP project expertise level is low.

Identification of Chemicals of Interest to the Department of Defense and U.S. Air Force Among the U.S. Environmental Protection Agency’s Integrated Risk Information System Chemicals that are Due for Reassessment of their Toxicity Values

DTIC Science & Technology

2010-03-16

Exceeded at ERP Soil and Groundwater Sites 86 A-2a. Identification of IRIS Chemicals of Interest on the ATSDR CERCLA Priority List of Hazardous...the Number (Bold Font) of Air Force ERP Samples in Which They Were Detected 317 A-4d. Air Force ERP Soil Samples: IRIS Chemicals of Interest...Ranked by the Number (Bold Font) of Air Force ERP Soil Samples in Which They Were Detected 333 A-4e. Air Force ERP Groundwater Samples: IRIS Chemicals of

Applying Real Options for Evaluating Investments in ERP Systems

NASA Astrophysics Data System (ADS)

Nakagane, Jun; Sekozawa, Teruji

This paper intends to verify effectiveness of real options approach for evaluating investments in Enterprise Resource Planning systems (ERP) and proves how important it is to disclose shadow options potentially embedded in ERP investment. The net present value (NPV) method is principally adopted to evaluate the value of ERP. However, the NPV method assumes no uncertainties exist in the object. It doesn't satisfy the current business circumstances which are filled with dynamic issues. Since the 1990s the effectiveness of option pricing models for Information System (IS) investment to solve issues in the NPV method has been discussed in the IS literature. This paper presents 3 business cases to review the practical advantages of such techniques for IS investments, especially ERP investments. The first case is EDI development. We evaluate the project by a new approach with lighting one of shadow options, EDI implementation. In the second case we reveal an ERP investment has an “expanding option” in a case of eliminating redundancy. The third case describes an option to contract which is deliberately slotted in ERP development to prepare transferring a manufacturing facility.

ERP Reliability Analysis (ERA) Toolbox: An open-source toolbox for analyzing the reliability of event-related brain potentials.

PubMed

Clayson, Peter E; Miller, Gregory A

2017-01-01

Generalizability theory (G theory) provides a flexible, multifaceted approach to estimating score reliability. G theory's approach to estimating score reliability has important advantages over classical test theory that are relevant for research using event-related brain potentials (ERPs). For example, G theory does not require parallel forms (i.e., equal means, variances, and covariances), can handle unbalanced designs, and provides a single reliability estimate for designs with multiple sources of error. This monograph provides a detailed description of the conceptual framework of G theory using examples relevant to ERP researchers, presents the algorithms needed to estimate ERP score reliability, and provides a detailed walkthrough of newly-developed software, the ERP Reliability Analysis (ERA) Toolbox, that calculates score reliability using G theory. The ERA Toolbox is open-source, Matlab software that uses G theory to estimate the contribution of the number of trials retained for averaging, group, and/or event types on ERP score reliability. The toolbox facilitates the rigorous evaluation of psychometric properties of ERP scores recommended elsewhere in this special issue. Copyright © 2016 Elsevier B.V. All rights reserved.

What Top-Down Task Sets Do for Us: An ERP Study on the Benefits of Advance Preparation in Visual Search

ERIC Educational Resources Information Center

Eimer, Martin; Kiss, Monika; Nicholas, Susan

2011-01-01

When target-defining features are specified in advance, attentional target selection in visual search is controlled by preparatory top-down task sets. We used ERP measures to study voluntary target selection in the absence of such feature-specific task sets, and to compare it to selection that is guided by advance knowledge about target features.…

Processing of visual food cues during bitter taste perception in female patients with binge-eating symptoms: A cross-modal ERP study.

PubMed

Schienle, Anne; Scharmüller, Wilfried; Schwab, Daniela

2017-11-01

In healthy individuals, the perception of an intense bitter taste decreased the reward value of visual food cues, as reflected by the reduction of a specific event-related brain potential (ERP), frontal late positivity. The current cross-modal ERP study investigated responses of female patients with binge-eating symptoms (BES) to this type of visual-gustatory stimulation. Women with BES (n=36) and female control participants (n=38) viewed food images after they rinsed their mouth with either bitter wormwood tea or water. Relative to controls, the patients showed elevated late positivity (LPP: 400-700ms) to the food images in the bitter condition. The LPP source was located in the medial prefrontal cortex. Both groups did not differ in the ratings for the fluids (intensity, bitterness, disgust). This ERP study showed that a bitter taste did not decrease late positivity to visual food cues (reflecting food reward) in women with BES. The atypical bitter responding might be a biological marker of this condition and possibly contributes to overeating. Future studies should additionally record food intake behavior to further investigate this mechanism. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past.

PubMed

Chen, Hong; Voss, Joel L; Guo, Chunyan

2012-07-30

False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory.

Event-related brain potentials that distinguish false memory for events that occurred only seconds in the past

PubMed Central

2012-01-01

Background False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs. Methods Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task. Results Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval. Conclusion Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory. PMID:22846189

When Does the Brain Distinguish between Genuine and Ambiguous Smiles? An ERP Study

ERIC Educational Resources Information Center

Calvo, Manuel G.; Marrero, Hipolito; Beltran, David

2013-01-01

Event-related brain potentials (ERPs) were recorded to assess the processing time course of ambiguous facial expressions with a smiling mouth but neutral, fearful, or angry eyes, in comparison with genuinely happy faces (a smile and happy eyes) and non-happy faces (neutral, fearful, or angry mouth and eyes). Participants judged whether the faces…

An ERP Study of the Processing of Subject and Object Relative Clauses in Japanese

ERIC Educational Resources Information Center

Ueno, Mieko; Garnsey, Susan M.

2008-01-01

Using reading times and event-related brain potentials (ERPs), we investigated the processing of Japanese subject and object relative clauses (SRs/ORs). Previous research on English relative clauses shows that ORs take longer to read (King & Just, 1991) and elicit anterior negativity between fillers and gaps (King & Kutas, 1995), which is…

From Project Management Capabilities to ERP Implementation Success: The Mediating Effect of IT Executives' Capabilities

ERIC Educational Resources Information Center

Touir, Maatallah

2016-01-01

Enterprise resource planning project implementation success is necessary for organizations to enhance productivity and achieve operational efficiency; however, the failure rates of ERP projects remain high, ranging between 10% and 90%, and costing organizations $500,000 to $300 million. The problem addressed in this study was the low success rate…

A Study of End Users' Perceived Usefulness of and Satisfaction with Enterprise Resource Planning Systems in Higher Education

ERIC Educational Resources Information Center

Su, Shau E. Eve

2012-01-01

Enterprise resource planning (ERP) systems have become necessities in today's educational arena and are used extensively to improve office productivity and institutional efficacy. As the implementation of ERP systems usually is costly and time-consuming, it is imperative for administrators to understand how end users adopt the introduced…

Does Solving Insight-Based Problems Differ from Solving Learning-Based Problems? Some Evidence from an ERP Study

ERIC Educational Resources Information Center

Leikin, Roza; Waisman, Ilana; Leikin, Mark

2016-01-01

We asked: "What are the similarities and differences in mathematical processing associated with solving learning-based and insight-based problems?" To answer this question, the ERP research procedure was employed with 69 male adolescent subjects who solved specially designed insight-based and learning-based tests. Solutions of…

Neural Localization of Semantic Context Effects in Electromagnetic and Hemodynamic Studies

ERIC Educational Resources Information Center

Van Petten, Cyma; Luka, Barbara J.

2006-01-01

Measures of electrical brain activity (event-related potentials, ERPs) have been useful in understanding language processing for several decades. Extant data suggest that the amplitude of the N400 component of the ERP is a general index of the ease or difficulty of retrieving stored conceptual knowledge associated with a word, which is dependent…

Hemodynamic and Electrophysiological Relationship Involved in Human Face Processing: Evidence from a Combined fMRI-ERP Study

ERIC Educational Resources Information Center

Iidaka, Tetsuya; Matsumoto, Atsushi; Haneda, Kaoruko; Okada, Tomohisa; Sadato, Norihiro

2006-01-01

Functional magnetic resonance imaging (fMRI) and event-related potential (ERP) experiments were conducted in the same group of subjects and with an identical task paradigm to investigate a possible relationship between hemodynamic and electrophysiological responses within the brain. The subjects were instructed to judge whether visually presented…

Comparing Public and Private Institutions That Have and Have Not Implemented Enterprise Resource Planning (ERP) Systems: A Resource Dependence Perspective

ERIC Educational Resources Information Center

Sendhil, Geetha R.

2012-01-01

The purpose of this national study was to utilize quantitative methods to examine institutional characteristics, financial resource variables, personnel variables, and customer variables of public and private institutions that have and have not implemented enterprise resource planning (ERP) systems, from a resource dependence perspective.…

How Does ERPsim Influence Students' Perceived Learning Outcomes in an Information Systems Course? An Empirical Study

ERIC Educational Resources Information Center

Chen, Liqiang; Keys, Anthony; Gaber, Donald

2015-01-01

It is a challenge for business students or even employees to understand business processes and enterprise software usage without involvement in real-world practices. Many business schools are using ERP software in their curriculum, aiming to expose students to real-world business practices. ERPsim is an Enterprise Resource Planning (ERP)…

Differential Effects of Aging on Processes Underlying Task Switching

ERIC Educational Resources Information Center

West, Robert; Travers, Stephanie

2008-01-01

In this study, we used event-related brain potentials (ERPs) to examine the effects of aging on processes underlying task switching. The response time data revealed an age-related increase in mixing costs before controlling for general slowing and no effect of aging on switching costs. In the cue-locked epoch, the ERP data revealed little effect…

Implicit Segmentation of a Stream of Syllables Based on Transitional Probabilities: An MEG Study

ERIC Educational Resources Information Center

Teinonen, Tuomas; Huotilainen, Minna

2012-01-01

Statistical segmentation of continuous speech, i.e., the ability to utilise transitional probabilities between syllables in order to detect word boundaries, is reflected in the brain's auditory event-related potentials (ERPs). The N1 and N400 ERP components are typically enhanced for word onsets compared to random syllables during active…

Assessing the Double Phonemic Representation in Bilingual Speakers of Spanish and English: An Electrophysiological Study

ERIC Educational Resources Information Center

Garcia-Sierra, Adrian; Ramirez-Esparza, Nairan; Silva-Pereyra, Juan; Siard, Jennifer; Champlin, Craig A.

2012-01-01

Event Related Potentials (ERPs) were recorded from Spanish-English bilinguals (N = 10) to test pre-attentive speech discrimination in two language contexts. ERPs were recorded while participants silently read magazines in English or Spanish. Two speech contrast conditions were recorded in each language context. In the "phonemic in English"…

Processing Focus Structure in L1 and L2 French: L2 Proficiency Effects on ERPs

ERIC Educational Resources Information Center

Reichle, Robert V.; Birdsong, David

2014-01-01

This study examined the event-related potentials (ERPs) elicited by focus processing among first language (L1) speakers and second language (L2) learners of French. Participants read wh-questions containing explicit focus marking, followed by responses instantiating contrastive and informational focus. We hypothesized that L2 proficiency would…

47 CFR 95.855 - Transmitter effective radiated power limitation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Transmitter effective radiated power limitation. The effective radiated power (ERP) of each CTS and RTU shall... with an ERP exceeding 20 watts. No mobile RTU may transmit with an ERP exceeding 4 watts. [64 FR 59663...

47 CFR 95.855 - Transmitter effective radiated power limitation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Transmitter effective radiated power limitation. The effective radiated power (ERP) of each CTS and RTU shall... with an ERP exceeding 20 watts. No mobile RTU may transmit with an ERP exceeding 4 watts. [64 FR 59663...

ERP implementation in rural health care.

PubMed

Trimmer, Kenneth J; Pumphrey, Lela D; Wiggins, Carla

2002-01-01

Enterprise resource planning (ERP) systems provide organizations with the opportunity to integrate individual, functionally-oriented information systems. Although much of the focus in the popular press has been placed on ERP systems in large for-profit organizations, small hospitals and clinics are candidates for ERP systems. Focusing information systems on critical success factors (CSFs) allows the organization to address a limited number of areas associated with performance. This limited number of factors can provide management with an insight into dimensions of information that must be addressed by a system. Focuses on CSFs for small health-care organizations. In addition, also considers factors critical to the implementation of health-care information systems. Presents two cases. The results indicate support for the continuing use of CSFs to help focus on the benefits of ERPs. Focusing on groups of tangible and intangible benefits can also assist the rural health-care organization in the use of ERPs.

ERP-based detection of brain pathology in rat models for preclinical Alzheimer's disease

NASA Astrophysics Data System (ADS)

Nouriziabari, Seyed Berdia

Early pathological features of Alzheimer's disease (AD) include the accumulation of hyperphosphorylated tau protein (HP-tau) in the entorhinal cortex and progressive loss of basal forebrain (BF) cholinergic neurons. These pathologies are known to remain asymptomatic for many years before AD is clinically diagnosed; however, they may induce aberrant brain processing which can be captured as an abnormality in event-related potentials (ERPs). Here, we examined cortical ERPs while a differential associative learning paradigm was applied to adult male rats with entorhinal HP-tau, pharmacological blockade of muscarinic acetylcholine receptors, or both conditions. Despite no impairment in differential associative and reversal learning, each pathological feature induced distinct abnormality in cortical ERPs to an extent that was sufficient for machine classifiers to accurately detect a specific type of pathology based on these ERP features. These results highlight a potential use of ERPs during differential associative learning as a biomarker for asymptomatic AD pathology.

Movement Interferes with Visuospatial Working Memory during the Encoding: An ERP Study

PubMed Central

Gunduz Can, Rumeysa; Schack, Thomas; Koester, Dirk

2017-01-01

The present study focuses on the functional interactions of cognition and manual action control. Particularly, we investigated the neurophysiological correlates of the dual-task costs of a manual-motor task (requiring grasping an object, holding it, and subsequently placing it on a target) for working memory (WM) domains (verbal and visuospatial) and processes (encoding and retrieval). Thirty participants were tested in a cognitive-motor dual-task paradigm, in which a single block (a verbal or visuospatial WM task) was compared with a dual block (concurrent performance of a WM task and a motor task). Event-related potentials (ERPs) were analyzed separately for the encoding and retrieval processes of verbal and visuospatial WM domains both in single and dual blocks. The behavioral analyses show that the motor task interfered with WM and decreased the memory performance. The performance decrease was larger for the visuospatial task compared with the verbal task, i.e., domain-specific memory costs were obtained. The ERP analyses show the domain-specific interference also at the neurophysiological level, which is further process-specific to encoding. That is, comparing the patterns of WM-related ERPs in the single block and dual block, we showed that visuospatial ERPs changed only for the encoding process when a motor task was performed at the same time. Generally, the present study provides evidence for domain- and process-specific interactions of a prepared manual-motor movement with WM (visuospatial domain during the encoding process). This study, therefore, provides an initial neurophysiological characterization of functional interactions of WM and manual actions in a cognitive-motor dual-task setting, and contributes to a better understanding of the neuro-cognitive mechanisms of motor action control. PMID:28611714

Family-based exposure and response prevention therapy for preschool-aged children with obsessive-compulsive disorder: a pilot randomized controlled trial.

PubMed

Lewin, Adam B; Park, Jennifer M; Jones, Anna M; Crawford, Erika A; De Nadai, Alessandro S; Menzel, Jessie; Arnold, Elysse B; Murphy, Tanya K; Storch, Eric A

2014-05-01

To examine the feasibility, acceptability and preliminary efficacy of family-based exposure/response prevention therapy (E/RP) versus treatment as usual (TAU) in a cohort of very young children with early onset obsessive-compulsive disorder (OCD). Thirty-one children ages 3-8 years (M = 5.8 years) with a primary diagnosis of OCD were randomized to E/RP or TAU. The E/RP condition received 12 sessions of family-based E/RP twice weekly over 6 weeks. Families were assessed at baseline, post-treatment, 1-month and 3-month follow up. The Children's Yale Brown Obsessive Compulsive Scale and Clinical Global Impression served as primary outcome measures. A large group effect emerged in favor of the E/RP group (d = 1.69). Sixty-five percent of the E/RP group was considered treatment responders as compared to 7% in the TAU group. Symptom remission was achieved in 35.2% of the E/RP group and 0% of the TAU group. There was no attrition and satisfaction was high; gains were maintained at 3 months. Even amongst children as young as 3 years, developmentally tailored E/RP is efficacious and well-tolerated in reducing OCD symptoms. Key adaptations for younger children include extensive parent involvement, targeting family accommodation, and frequent meetings while delivering a full course of E/RP. NCT01447966 http://clinicaltrials.gov/ct2/show/NCT01447966?term=ocd+and+st+petersburg&rank=1. Copyright © 2014 Elsevier Ltd. All rights reserved.

How to validate similarity in linear transform models of event-related potentials between experimental conditions?

PubMed

Cong, Fengyu; Lin, Qiu-Hua; Astikainen, Piia; Ristaniemi, Tapani

2014-10-30

It is well-known that data of event-related potentials (ERPs) conform to the linear transform model (LTM). For group-level ERP data processing using principal/independent component analysis (PCA/ICA), ERP data of different experimental conditions and different participants are often concatenated. It is theoretically assumed that different experimental conditions and different participants possess the same LTM. However, how to validate the assumption has been seldom reported in terms of signal processing methods. When ICA decomposition is globally optimized for ERP data of one stimulus, we gain the ratio between two coefficients mapping a source in brain to two points along the scalp. Based on such a ratio, we defined a relative mapping coefficient (RMC). If RMCs between two conditions for an ERP are not significantly different in practice, mapping coefficients of this ERP between the two conditions are statistically identical. We examined whether the same LTM of ERP data could be applied for two different stimulus types of fearful and happy facial expressions. They were used in an ignore oddball paradigm in adult human participants. We found no significant difference in LTMs (based on ICASSO) of N170 responses to the fearful and the happy faces in terms of RMCs of N170. We found no methods for straightforward comparison. The proposed RMC in light of ICA decomposition is an effective approach for validating the similarity of LTMs of ERPs between experimental conditions. This is very fundamental to apply group-level PCA/ICA to process ERP data. Copyright © 2014 Elsevier B.V. All rights reserved.

Differential effects of emotional cues on components of prospective memory: an ERP study

PubMed Central

Cona, Giorgia; Kliegel, Matthias; Bisiacchi, Patrizia S.

2015-01-01

So far, little is known about the neurocognitive mechanisms associated with emotion effects on prospective memory (PM) performance. Thus, this study aimed at disentangling possible mechanisms for the effects of emotional valence of PM cues on the distinct phases composing PM by investigating event-related potentials (ERPs). Participants were engaged in an ongoing N-back task while being required to perform a PM task. The emotional valence of both the ongoing pictures and the PM cues was manipulated (pleasant, neutral, unpleasant). ERPs were recorded during the PM phases, such as encoding, maintenance, and retrieval of the intention. A recognition task including PM cues and ongoing stimuli was also performed at the end of the sessions. ERP results suggest that emotional PM cues not only trigger an automatic, bottom-up, capture of attention, but also boost a greater allocation of top-down processes. These processes seem to be recruited to hold attention toward the emotional stimuli and to retrieve the intention from memory, likely because of the motivational significance of the emotional stimuli. Moreover, pleasant PM cues seemed to modulate especially the prospective component, as revealed by changes in the amplitude of the ERP correlates of strategic monitoring as a function of the relevance of the valence for the PM task. Unpleasant pictures seemed to modulate especially the retrospective component, as revealed by the largest old/new effect being elicited by unpleasant PM pictures in the recognition task. PMID:25674061

Local and Global Auditory Processing: Behavioral and ERP Evidence

PubMed Central

Sanders, Lisa D.; Poeppel, David

2007-01-01

Differential processing of local and global visual features is well established. Global precedence effects, differences in event-related potentials (ERPs) elicited when attention is focused on local versus global levels, and hemispheric specialization for local and global features all indicate that relative scale of detail is an important distinction in visual processing. Observing analogous differential processing of local and global auditory information would suggest that scale of detail is a general organizational principle of the brain. However, to date the research on auditory local and global processing has primarily focused on music perception or on the perceptual analysis of relatively higher and lower frequencies. The study described here suggests that temporal aspects of auditory stimuli better capture the local-global distinction. By combining short (40 ms) frequency modulated tones in series to create global auditory patterns (500 ms), we independently varied whether pitch increased or decreased over short time spans (local) and longer time spans (global). Accuracy and reaction time measures revealed better performance for global judgments and asymmetric interference that were modulated by amount of pitch change. ERPs recorded while participants listened to identical sounds and indicated the direction of pitch change at the local or global levels provided evidence for differential processing similar to that found in ERP studies employing hierarchical visual stimuli. ERP measures failed to provide evidence for lateralization of local and global auditory perception, but differences in distributions suggest preferential processing in more ventral and dorsal areas respectively. PMID:17113115

Effects of mindfulness-based cognitive therapy on neurophysiological correlates of performance monitoring in adult attention-deficit/hyperactivity disorder.

PubMed

Schoenberg, Poppy L A; Hepark, Sevket; Kan, Cornelis C; Barendregt, Henk P; Buitelaar, Jan K; Speckens, Anne E M

2014-07-01

To examine whether mindfulness-based cognitive therapy (MBCT) would enhance attenuated amplitudes of event-related potentials (ERPs) indexing performance monitoring biomarkers of attention-deficit/hyperactivity disorder (ADHD). Fifty adult ADHD patients took part in a randomised controlled study investigating ERP and clinical measures pre-to-post MBCT. Twenty-six patients were randomly allocated to MBCT, 24 to a wait-list control. Main outcome measures included error processing (ERN, Pe), conflict monitoring (NoGo-N2), and inhibitory control (NoGo-P3) ERPs concomitant to a continuous performance task (CPT-X). Inattention and hyperactivity-impulsivity ADHD symptoms, psychological distress and social functioning, and mindfulness skills were also assessed. MBCT was associated with increased Pe and NoGo-P3 amplitudes, coinciding with reduced 'hyperactivity/impulsivity' and 'inattention' symptomatology. Specific to the MBCT; enhanced Pe amplitudes correlated with a decrease in hyperactivity/impulsivity symptoms and increased 'act-with-awareness' mindfulness skill, whereas, enhanced P3 correlated with amelioration in inattention symptoms. MBCT enhanced ERP amplitudes associated with motivational saliency and error awareness, leading to improved inhibitory regulation. MBCT suggests having comparable modulation on performance monitoring ERP amplitudes as pharmacological treatments. Further study and development of MBCT as a treatment for ADHD is warranted, in addition to its potential scope for clinical applicability to broader defined externalising disorders and clinical problems associated with impairments of the prefrontal cortex. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

ERP-Variations on Time Scales Between Hours and Months Derived From GNSS Observations

NASA Astrophysics Data System (ADS)

Weber, R.; Englich, S.; Mendes Cerveira, P.

2007-05-01

Current observations gained by the space geodetic techniques, especially VLBI, GPS and SLR, allow for the determination of Earth Rotation Parameters (ERPs - polar motion, UT1/LOD) with unprecedented accuracy and temporal resolution. This presentation focuses on contributions to the ERP recovery provided by satellite navigation systems (primarily GPS). The IGS (International GNSS Service), for example, currently provides daily polar motion with an accuracy of less than 0.1mas and LOD estimates with an accuracy of a few microseconds. To study more rapid variations in polar motion and LOD we established in a first step a high resolution (hourly resolution) ERP-time series from GPS observation data of the IGS network covering the year 2005. The calculations were carried out by means of the Bernese GPS Software V5.0 considering observations from a subset of 113 fairly stable stations out of the IGS05 reference frame sites. From these ERP time series the amplitudes of the major diurnal and semidiurnal variations caused by ocean tides are estimated. After correcting the series for ocean tides the remaining geodetic observed excitation is compared with variations of atmospheric excitation (AAM). To study the sensitivity of the estimates with respect to the applied mapping function we applied both the widely used NMF (Niell Mapping Function) and the VMF1 (Vienna Mapping Function 1). In addition, based on computations covering two months in 2005, the potential improvement due to the use of additional GLONASS data will be discussed.

EPA Administrative Order on Consent (AOC) with ERP Compliant Coke, LLC

EPA Pesticide Factsheets

This Administrative Order on Consent with ERP Compliant Coke was effective August 2016. The Walter Coke facility located in North Birmingham was purchased by ERP Compliant Coke, LLC in February 2016 out of bankruptcy proceedings.

How personal earthquake experience impacts on the Stroop interference effect: an event-related potential study.

PubMed

Qiu, Jiang; Su, Yanhua; Li, Hong; Wei, Dongtao; Tu, Shen; Zhang, Qinglin

2010-11-01

Event-related brain potentials (ERPs) were measured when 24 Chinese subjects performed the classical Stroop task. All of subjects had experienced the great Sichuan earthquake (5/12), with 12 people in each of the Far (Chengdu city) and the Close (Deyang city) earthquake experience groups. The behavioral data showed that the Stroop task yielded a robust Stroop interference effect as indexed by longer RT for incongruent than congruent color words in both the Chengdu and Deyang groups. Scalp ERP data showed that incongruent stimuli elicited a more negative ERP deflection (N400-600; Stroop interference effect) than did congruent stimuli between 400-600 ms in the Chengdu group, while the Stroop interference ERP effect was not found in the Deyang group. Dipole source analysis localized the generator of the N400-600 in the right prefrontal cortex (PFC) and was possibly related to conflict monitoring and cognitive control. Copyright © 2010 Society for Psychophysiological Research.

The phonotactic influence on the perception of a consonant cluster /pt/ by native English and native Polish listeners: A behavioral and event related potential (ERP) study

PubMed Central

Wagner, Monica; Shafer, Valerie L.; Martin, Brett; Steinschneider, Mitchell

2013-01-01

The effect of exposure to the contextual features of the /pt/ cluster was investigated in native-English and native-Polish listeners using behavioral and event-related potential (ERP) methodology. Both groups experience the /pt/ cluster in their languages, but only the Polish group experiences the cluster in the context of word onset examined in the current experiment. The /st/ cluster was used as an experimental control. ERPs were recorded while participants identified the number of syllables in the second word of nonsense word pairs. The results found that only Polish listeners accurately perceived the /pt/ cluster and perception was reflected within a late positive component of the ERP waveform. Furthermore, evidence of discrimination of /pt/ and /pǝt/ onsets in the neural signal was found even for non-native listeners who could not perceive the difference. These findings suggest that exposure to phoneme sequences in highly specific contexts may be necessary for accurate perception. PMID:22867752

Serial position effects in free memory recall--An ERP-study.

PubMed

Wiswede, Daniel; Rüsseler, Jascha; Münte, Thomas F

2007-05-01

Event-related brain potentials (ERPs) elicited by recalled and non-recalled words were recorded from 18 female subjects to investigate primacy and recency effects in free memory recall. The typical pattern of a serial position curve (SPC) was obtained with words presented at first and final positions in a list recalled better than words presented in the middle of a list. A marked positivity is seen in the ERPs for words on Primacy, but not on Recency positions at frontocentral electrodes. In contrast, ERP amplitudes on parietal electrodes resemble the SPC seen in behavioral data: P300 amplitude is largest for words on Primacy and Recency positions and attenuated on Plateau positions. Furthermore, subjects with a clear Primacy effect in behavioral data show a distinct frontal positive slow wave for Primacy words only, whereas subjects without a clear primacy effect show a frontal "difference due to subsequent memory" (DM) effect for Primacy and Plateau words. These results are discussed in the framework of working memory and distinctiveness.

Processing Sentences with Literal versus Figurative Use of Verbs: An ERP Study with Children with Language Impairments, Nonverbal Impairments, and Typical Development

PubMed Central

Lorusso, Maria Luisa; Burigo, Michele; Borsa, Virginia; Molteni, Massimo

2015-01-01

Forty native Italian children (age 6–15) performed a sentence plausibility judgment task. ERP recordings were available for 12 children with specific language impairment (SLI), 11 children with nonverbal learning disabilities (NVLD), and 13 control children. Participants listened to verb-object combinations and judged them as acceptable or unacceptable. Stimuli belonged to four conditions, where concreteness and congruency were manipulated. All groups made more errors responding to abstract and to congruent sentences. Moreover, SLI participants performed worse than NVLD participants with abstract sentences. ERPs were analyzed in the time window 300–500 ms. SLI children show atypical, reversed effects of concreteness and congruence as compared to control and NVLD children, respectively. The results suggest that linguistic impairments disrupt abstract language processing more than visual-motor impairments. Moreover, ROI and SPM analyses of ERPs point to a predominant involvement of the left rather than the right hemisphere in the comprehension of figurative expressions. PMID:26246693

How stimulation speed affects Event-Related Potentials and BCI performance.

PubMed

Höhne, Johannes; Tangermann, Michael

2012-01-01

In most paradigms for Brain-Computer Interfaces (BCIs) that are based on Event-Related Potentials (ERPs), stimuli are presented with a pre-defined and constant speed. In order to boost BCI performance by optimizing the parameters of stimulation, this offline study investigates the impact of the stimulus onset asynchrony (SOA) on ERPs and the resulting classification accuracy. The SOA is defined as the time between the onsets of two consecutive stimuli, which represents a measure for stimulation speed. A simple auditory oddball paradigm was tested in 14 SOA conditions with a SOA between 50 ms and 1000 ms. Based on an offline ERP analysis, the BCI performance (quantified by the Information Transfer Rate, ITR in bits/min) was simulated. A great variability in the simulated BCI performance was observed within subjects (N=11). This indicates a potential increase in BCI performance (≥ 1.6 bits/min) for ERP-based paradigms, if the stimulation speed is specified for each user individually.

Testing asymmetries in noncognate translation priming: Evidence from RTs and ERPs

PubMed Central

SCHOONBAERT, SOFIE; HOLCOMB, PHILLIP J.; GRAINGER, JONATHAN; HARTSUIKER, ROBERT J.

2012-01-01

In this study, English–French bilinguals performed a lexical decision task while reaction times (RTs) and event related potentials (ERPs) were measured to L2 targets, preceded by noncognate L1 translation primes versus L1 unrelated primes (Experiment 1a) and vice versa (Experiment 1b). The prime–target stimulus onset asynchrony was 120 ms. Significant masked translation priming was observed, indicated by faster reaction times and a decreased N400 for translation pairs as opposed to unrelated pairs, both from L1 to L2 (Experiment 1a) and from L2 to L1 (Experiment 1b), with the latter effect being weaker (RTs) and less longer lasting (ERPs). A translation priming effect was also found in the N250 ERP component, and this effect was stronger and earlier in the L2 to L1 priming direction than the reverse. The results are discussed with respect to possible mechanisms at the basis of asymmetric translation priming effects in bilinguals. PMID:20557483

Evaluation of effectiveness of information systems implementation in organization (by example of ERP-systems)

NASA Astrophysics Data System (ADS)

Demyanova, O. V.; Andreeva, E. V.; Sibgatullina, D. R.; Kireeva-Karimova, A. M.; Gafurova, A. Y.; Zakirova, Ch S.

2018-05-01

ERP in a modern enterprise information system allowed optimizing internal business processes, reducing production costs and increasing the attractiveness of enterprises for investors. It is an important component of success in the competition and an important condition for attracting investments in the key sector of the state. A vivid example of these systems are enterprise information systems using the methodology of ERP (Enterprise Resource Planning - enterprise resource planning). ERP is an integrated set of methods, processes, technologies and tools. It is based on: supply chain management; advanced planning and scheduling; sales automation; tool responsible for configuring; final resource planning; intelligence business; OLAP technology; block e- Commerce; management of product data. The main purpose of ERP systems is the automation of interrelated processes of planning, accounting and management in key areas of the company. ERP systems are automated systems that effectively address complex problems, including optimal allocation of business resources, ensuring quick and efficient delivery of goods and services to the consumer. Knowledge embedded in ERP systems provided enterprise-wide automation to introduce the activities of all functional departments of the company as a single complex system. At the level of quality estimates, most managers understand that the implementations of ERP systems is a necessary and useful procedure. Assessment of the effectiveness of the information systems implementation is relevant.

Unfolding the Spatial and Temporal Neural Processing of Making Dishonest Choices

PubMed Central

Wang, Zhaoxin; Chan, Chetwyn C. H.

2016-01-01

To understand the neural processing that underpins dishonest behavior in an economic exchange game task, this study employed both functional magnetic resonance imaging (fMRI) and event-related potential (ERP) methodologies to examine the neural conditions of 25 participants while they were making either dishonest or honest choices. It was discovered that dishonest choices, contrary to honest choices, elicited stronger fMRI activations in bilateral striatum and anterior insula. It also induced fluctuations in ERP amplitudes within two time windows, which are 270–30 milliseconds before and 110–290 milliseconds after the response, respectively. Importantly, when making either dishonest or honest choices, human and computer counterparts were associated with distinct fMRI activations in the left insula and different ERP amplitudes at medial and right central sites from 80 milliseconds before to 250 milliseconds after the response. These results support the hypothesis that there would be distinct neural processing during making dishonest decisions, especially when the subject considers the interests of the counterpart. Furthermore, the fMRI and ERP findings, together with ERP source reconstruction, clearly delineate the temporal sequence of the neural processes of a dishonest decision: the striatum is activated before response, then the left insula is involved around the time of response, and finally the thalamus is activated after response. PMID:27096474

Event-related potential correlates of declarative and non-declarative sequence knowledge.

PubMed

Ferdinand, Nicola K; Rünger, Dennis; Frensch, Peter A; Mecklinger, Axel

2010-07-01

The goal of the present study was to demonstrate that declarative and non-declarative knowledge acquired in an incidental sequence learning task contributes differentially to memory retrieval and leads to dissociable ERP signatures in a recognition memory task. For this purpose, participants performed a sequence learning task and were classified as verbalizers, partial verbalizers, or nonverbalizers according to their ability to verbally report the systematic response sequence. Thereafter, ERPs were recorded in a recognition memory task time-locked to sequence triplets that were either part of the previously learned sequence or not. Although all three groups executed old sequence triplets faster than new triplets in the recognition memory task, qualitatively distinct ERP patterns were found for participants with and without reportable knowledge. Verbalizers and, to a lesser extent, partial verbalizers showed an ERP correlate of recollection for parts of the incidentally learned sequence. In contrast, nonverbalizers showed a different ERP effect with a reverse polarity that might reflect priming. This indicates that an ensemble of qualitatively different processes is at work when declarative and non-declarative sequence knowledge is retrieved. By this, our findings favor a multiple-systems view postulating that explicit and implicit learning are supported by different and functionally independent systems. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Infant Directed Speech Enhances Statistical Learning in Newborn Infants: An ERP Study

PubMed Central

Teinonen, Tuomas; Tervaniemi, Mari; Huotilainen, Minna

2016-01-01

Statistical learning and the social contexts of language addressed to infants are hypothesized to play important roles in early language development. Previous behavioral work has found that the exaggerated prosodic contours of infant-directed speech (IDS) facilitate statistical learning in 8-month-old infants. Here we examined the neural processes involved in on-line statistical learning and investigated whether the use of IDS facilitates statistical learning in sleeping newborns. Event-related potentials (ERPs) were recorded while newborns were exposed to12 pseudo-words, six spoken with exaggerated pitch contours of IDS and six spoken without exaggerated pitch contours (ADS) in ten alternating blocks. We examined whether ERP amplitudes for syllable position within a pseudo-word (word-initial vs. word-medial vs. word-final, indicating statistical word learning) and speech register (ADS vs. IDS) would interact. The ADS and IDS registers elicited similar ERP patterns for syllable position in an early 0–100 ms component but elicited different ERP effects in both the polarity and topographical distribution at 200–400 ms and 450–650 ms. These results provide the first evidence that the exaggerated pitch contours of IDS result in differences in brain activity linked to on-line statistical learning in sleeping newborns. PMID:27617967

Online processing of moral transgressions: ERP evidence for spontaneous evaluation.

PubMed

Leuthold, Hartmut; Kunkel, Angelika; Mackenzie, Ian G; Filik, Ruth

2015-08-01

Experimental studies using fictional moral dilemmas indicate that both automatic emotional processes and controlled cognitive processes contribute to moral judgments. However, not much is known about how people process socio-normative violations that are more common to their everyday life nor the time-course of these processes. Thus, we recorded participants' electrical brain activity while they were reading vignettes that either contained morally acceptable vs unacceptable information or text materials that contained information which was either consistent or inconsistent with their general world knowledge. A first event-related brain potential (ERP) positivity peaking at ∼200 ms after critical word onset (P200) was larger when this word involved a socio-normative or knowledge-based violation. Subsequently, knowledge-inconsistent words triggered a larger centroparietal ERP negativity at ∼320 ms (N400), indicating an influence on meaning construction. In contrast, a larger ERP positivity (larger late positivity), which also started at ∼320 ms after critical word onset, was elicited by morally unacceptable compared with acceptable words. We take this ERP positivity to reflect an implicit evaluative (good-bad) categorization process that is engaged during the online processing of moral transgressions. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Effects of cooperating and conflicting prosody in spoken English garden path sentences: ERP evidence for the boundary deletion hypothesis.

PubMed

Pauker, Efrat; Itzhak, Inbal; Baum, Shari R; Steinhauer, Karsten

2011-10-01

In reading, a comma in the wrong place can cause more severe misunderstandings than the lack of a required comma. Here, we used ERPs to demonstrate that a similar effect holds for prosodic boundaries in spoken language. Participants judged the acceptability of temporarily ambiguous English "garden path" sentences whose prosodic boundaries were either in line or in conflict with the actual syntactic structure. Sentences with incongruent boundaries were accepted less than those with missing boundaries and elicited a stronger on-line brain response in ERPs (N400/P600 components). Our results support the notion that mentally deleting an overt prosodic boundary is more costly than postulating a new one and extend previous findings, suggesting an immediate role of prosody in sentence comprehension. Importantly, our study also provides new details on the profile and temporal dynamics of the closure positive shift (CPS), an ERP component assumed to reflect prosodic phrasing in speech and music in real time. We show that the CPS is reliably elicited at the onset of prosodic boundaries in English sentences and is preceded by negative components. Its early onset distinguishes the speech CPS in adults both from prosodic ERP correlates in infants and from the "music CPS" previously reported for trained musicians.

Do cultures vary in self-enhancement? ERP, behavioral, and self-report evidence.

PubMed

Hampton, Ryan S; Varnum, Michael E W

2017-08-02

Psychologists have long debated whether self-enhancement is universal or varies across cultures. Extant studies using explicit and implicit measures have provided mixed results. In this study (N = 93; 35 European American, 58 Chinese: 28 tested in English, 30 tested in Mandarin), we measured self-enhancement covertly using an ERP paradigm. Self-enhancement was also assessed via self-report and reaction-time based measures. Americans showed strong evidence of self-enhancement across all measures, whereas this effect was absent or weaker among Chinese, who instead showed an other-enhancing bias across measures. Language did not affect self-enhancement tendencies among Chinese participants, with the exception of one self-report measure. Nor did the two cultural groups differ in enhancement for a close other. This is the first study to directly compare self-enhancement across cultural groups using ERPs and provides evidence that positive self-regard does indeed vary by culture.

Selective attention and the "Asynchrony Theory" in native Hebrew-speaking adult dyslexics: Behavioral and ERPs measures.

PubMed

Menashe, Shay

2017-01-01

The main aim of the present study was to determine whether adult dyslexic readers demonstrate the "Asynchrony Theory" (Breznitz [Reading Fluency: Synchronization of Processes, Lawrence Erlbaum and Associates, Mahwah, NJ, USA, 2006]) when selective attention is studied. Event-related potentials (ERPs) and behavioral parameters were collected from nonimpaired readers group and dyslexic readers group performing alphabetic and nonalphabetic tasks. The dyslexic readers group was found to demonstrate asynchrony between the auditory and the visual modalities when it came to processing alphabetic stimuli. These findings were found both for behavioral and ERPs parameters. Unlike the dyslexic readers, the nonimpaired readers showed synchronized speed of processing in the auditory and the visual modalities while processing alphabetic stimuli. The current study suggests that established reading is dependent on a synchronization between the auditory and the visual modalities even when it comes to selective attention.

Verbal predicates foster conscious recollection but not familiarity of a task-irrelevant perceptual feature--an ERP study.

PubMed

Ecker, Ullrich K H; Arend, Anna M; Bergström, Kirstin; Zimmer, Hubert D

2009-09-01

Research on the effects of perceptual manipulations on recognition memory has suggested that (a) recollection is selectively influenced by task-relevant information and (b) familiarity can be considered perceptually specific. The present experiment tested divergent assumptions that (a) perceptual features can influence conscious object recollection via verbal code despite being task-irrelevant and that (b) perceptual features do not influence object familiarity if study is verbal-conceptual. At study, subjects named objects and their presentation colour; this was followed by an old/new object recognition test. Event-related potentials (ERP) showed that a study-test manipulation of colour impacted selectively on the ERP effect associated with recollection, while a size manipulation showed no effect. It is concluded that (a) verbal predicates generated at study are potent episodic memory agents that modulate recollection even if the recovered feature information is task-irrelevant and (b) commonly found perceptual match effects on familiarity critically depend on perceptual processing at study.

Beliefs and Attitudes Associated with ERP Adoption Behaviours: A Grounded Theory Study from IT Manager and End-user Perspectives

NASA Astrophysics Data System (ADS)

Arunthari, Santipat; Hasan, Helen

(1998, p. 121) defines an Enterprise Resource Planning (ERP) system as an enterprise system that promises seamless integration of all information flowing through a company, including financial and accounting information, human resource information, supply chain information, customer information. ERP systems came on the scene in the early 1990s as a response to the proliferation of standalone business applications to service these separate information needs in most large organisations. Enterprise wide projects, such as data warehousing, requiring integrated approaches to organisational operations and information management were inhibited through a proliferation of incompatible off-the-shelf packages, in-house developments and aging legacy systems.

Stimulus Dependency of Object-Evoked Responses in Human Visual Cortex: An Inverse Problem for Category Specificity

PubMed Central

Graewe, Britta; De Weerd, Peter; Farivar, Reza; Castelo-Branco, Miguel

2012-01-01

Many studies have linked the processing of different object categories to specific event-related potentials (ERPs) such as the face-specific N170. Despite reports showing that object-related ERPs are influenced by visual stimulus features, there is consensus that these components primarily reflect categorical aspects of the stimuli. Here, we re-investigated this idea by systematically measuring the effects of visual feature manipulations on ERP responses elicited by both structure-from-motion (SFM)-defined and luminance-defined object stimuli. SFM objects elicited a novel component at 200–250 ms (N250) over parietal and posterior temporal sites. We found, however, that the N250 amplitude was unaffected by restructuring SFM stimuli into meaningless objects based on identical visual cues. This suggests that this N250 peak was not uniquely linked to categorical aspects of the objects, but is strongly determined by visual stimulus features. We provide strong support for this hypothesis by parametrically manipulating the depth range of both SFM- and luminance-defined object stimuli and showing that the N250 evoked by SFM stimuli as well as the well-known N170 to static faces were sensitive to this manipulation. Importantly, this effect could not be attributed to compromised object categorization in low depth stimuli, confirming a strong impact of visual stimulus features on object-related ERP signals. As ERP components linked with visual categorical object perception are likely determined by multiple stimulus features, this creates an interesting inverse problem when deriving specific perceptual processes from variations in ERP components. PMID:22363479

Stimulus dependency of object-evoked responses in human visual cortex: an inverse problem for category specificity.

PubMed

Graewe, Britta; De Weerd, Peter; Farivar, Reza; Castelo-Branco, Miguel

2012-01-01

Many studies have linked the processing of different object categories to specific event-related potentials (ERPs) such as the face-specific N170. Despite reports showing that object-related ERPs are influenced by visual stimulus features, there is consensus that these components primarily reflect categorical aspects of the stimuli. Here, we re-investigated this idea by systematically measuring the effects of visual feature manipulations on ERP responses elicited by both structure-from-motion (SFM)-defined and luminance-defined object stimuli. SFM objects elicited a novel component at 200-250 ms (N250) over parietal and posterior temporal sites. We found, however, that the N250 amplitude was unaffected by restructuring SFM stimuli into meaningless objects based on identical visual cues. This suggests that this N250 peak was not uniquely linked to categorical aspects of the objects, but is strongly determined by visual stimulus features. We provide strong support for this hypothesis by parametrically manipulating the depth range of both SFM- and luminance-defined object stimuli and showing that the N250 evoked by SFM stimuli as well as the well-known N170 to static faces were sensitive to this manipulation. Importantly, this effect could not be attributed to compromised object categorization in low depth stimuli, confirming a strong impact of visual stimulus features on object-related ERP signals. As ERP components linked with visual categorical object perception are likely determined by multiple stimulus features, this creates an interesting inverse problem when deriving specific perceptual processes from variations in ERP components.

A longitudinal examination of event-related potentials sensitive to monetary reward and loss feedback from late childhood to middle adolescence.

PubMed

Kujawa, Autumn; Carroll, Ashley; Mumper, Emma; Mukherjee, Dahlia; Kessel, Ellen M; Olino, Thomas; Hajcak, Greg; Klein, Daniel N

2017-11-04

Brain regions involved in reward processing undergo developmental changes from childhood to adolescence, and alterations in reward-related brain function are thought to contribute to the development of psychopathology. Event-related potentials (ERPs), such as the reward positivity (RewP) component, are valid measures of reward responsiveness that are easily assessed across development and provide insight into temporal dynamics of reward processing. Little work has systematically examined developmental changes in ERPs sensitive to reward. In this longitudinal study of 75 youth assessed 3 times across 6years, we used principal components analyses (PCA) to differentiate ERPs sensitive to monetary reward and loss feedback in late childhood, early adolescence, and middle adolescence. We then tested reliability of, and developmental changes in, ERPs. A greater number of ERP components differentiated reward and loss feedback in late childhood compared to adolescence, but components in childhood accounted for only a small proportion of variance. A component consistent with RewP was the only one to consistently emerge at each of the 3 assessments. RewP demonstrated acceptable reliability, particularly from early to middle adolescence, though reliability estimates varied depending on scoring approach and developmental period. The magnitude of the RewP component did not significantly change across time. Results provide insight into developmental changes in the structure of ERPs sensitive to reward, and indicate that RewP is a consistently observed and relatively stable measure of reward responsiveness, particularly across adolescence. Copyright © 2017. Published by Elsevier B.V.

The time-course of activation in the dorsal and ventral visual streams during landmark cueing and perceptual discrimination tasks.

PubMed

Lambert, Anthony J; Wootton, Adrienne

2017-08-01

Different patterns of high density EEG activity were elicited by the same peripheral stimuli, in the context of Landmark Cueing and Perceptual Discrimination tasks. The C1 component of the visual event-related potential (ERP) at parietal - occipital electrode sites was larger in the Landmark Cueing task, and source localisation suggested greater activation in the superior parietal lobule (SPL) in this task, compared to the Perceptual Discrimination task, indicating stronger early recruitment of the dorsal visual stream. In the Perceptual Discrimination task, source localisation suggested widespread activation of the inferior temporal gyrus (ITG) and fusiform gyrus (FFG), structures associated with the ventral visual stream, during the early phase of the P1 ERP component. Moreover, during a later epoch (171-270ms after stimulus onset) increased temporal-occipital negativity, and stronger recruitment of ITG and FFG were observed in the Perceptual Discrimination task. These findings illuminate the contrasting functions of the dorsal and ventral visual streams, to support rapid shifts of attention in response to contextual landmarks, and conscious discrimination, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

About turn: how object orientation affects categorisation and mental rotation.

PubMed

Milivojevic, Branka; Hamm, Jeff P; Corballis, Michael C

2011-11-01

High-density ERPs evoked by rotated alphanumeric characters were examined to determine how neural processing is affected by stimulus orientation during letter/digit classifications and during mirror/normal discriminations. The former task typically produces response times that are unaffected by stimulus orientation while the latter is thought to require mental rotation. Sensitivity to orientation was first observed around 100-140 ms and this effect was attributed to differences in low-level features between vertical and oblique orientations. Subsequently, character misorientation amplified the N170, a neural marker of object classification, between 160 and 220 ms. Top-down processing is reflected in the ERPs beginning at 280-320 ms and this time range may reflect binding of ventral and dorsal stream information. In the case of mirror-normal discrimination these top-down processes can lead to mental rotation between 340 and 700 ms. Therefore, although neural processing reflects object orientation, these effects do not translate into increases in reaction-times or impaired accuracy for categorisation, and precede those that do in the mental-rotation task. Copyright © 2011 Elsevier Ltd. All rights reserved.

Clinical applications of cognitive event-related potentials in Alzheimer's disease.

PubMed

Olichney, John M; Hillert, Dieter G

2004-02-01

This article has reviewed several abnormalities in the cognitive ERPs of AD patients. These abnormalities are prominent from latencies of approximately 200 msec and later. In contrast, sensory-dependent evoked potentials, such as N100, are generally normal in AD. This finding is as one familiar with the neuropathology of AD would predict. Predilection sites in early AD include the medial temporal lobe, other limbic areas, and multimodal association cortices with sparing of primary sensory areas. Unimodal association cortex is involved in AD, but not as heavily as multimodal cortex. Particular advantages of studying a given ERP paradigm or component depend largely on the specific application or hypothesis being tested. A P300 paradigm can be useful in detecting a disorder of attention or in quantifying the effects of drugs that improve attention, such as the cholinesterase inhibitors. For the early diagnosis of AD or other memory disorders, a word-repetition paradigm with an explicit recognition task or one that fosters associative learning would be recommended. This article has discussed potential use of N400 in tracking disease progression. ERPs provide a flexible and powerful technique, with superb temporal resolution, which can be used as a probe into subtle "subclinical" abnormalities of cognitive processes. Despite being applied to AD for about 25 years since the early P300 studies, the full potential of ERPs in helping diagnose and treat AD patients has yet to be realized. In this era of rapidly evolving brain-imaging techniques, electrophysiologic data are important in advancing understanding of cognition. Brain-mapping techniques that can inform where and when key cognitive processes occur are finally emerging. A final example of potential clinical application of cognitive ERPs is in the development of rational combinational treatment of cognitive enhancing drugs. Along these lines, P300 investigations in epilepsy proved helpful in ranking the cognitive side effects of anticonvulsant drugs. Drug studies that use 2 x 2 combinational designs, which compare the effects of drug A, drug B, with A + B, are currently prohibitively expensive for full-scale clinical trials in AD. It is likely that precise ERP measures could hasten drug development in several ways. Smaller samples could be used, at lower cost, to test the cognitive effects of each specific drug combination. Optimal doses of combinational therapy perhaps could be identified by repeated within-subject ERP measures. Longitudinal changes in the ERP hold promise as a marker of individual responsivity to a particular agent, which could have diagnostic utility (eg, testing response to cholinergic or dopaminergic therapy). This horizon and many others remain wide open for well-planned explorations.

How and When Accentuation Influences Temporally Selective Attention and Subsequent Semantic Processing during On-Line Spoken Language Comprehension: An ERP Study

ERIC Educational Resources Information Center

Li, Xiao-qing; Ren, Gui-qin

2012-01-01

An event-related brain potentials (ERP) experiment was carried out to investigate how and when accentuation influences temporally selective attention and subsequent semantic processing during on-line spoken language comprehension, and how the effect of accentuation on attention allocation and semantic processing changed with the degree of…

An Event-Related Potential (ERP) Investigation of Filler-Gap Processing in Native and Second Language Speakers

ERIC Educational Resources Information Center

Dallas, Andrea; DeDe, Gayle; Nicol, Janet

2013-01-01

The current study employed a neuro-imaging technique, Event-Related Potentials (ERP), to investigate real-time processing of sentences containing filler-gap dependencies by late-learning speakers of English as a second language (L2) with a Chinese native language background. An individual differences approach was also taken to examine the role of…

Deduction Electrified: ERPs Elicited by the Processing of Words in Conditional Arguments

ERIC Educational Resources Information Center

Bonnefond, Mathilde; Van der Henst, Jean-Baptiste

2013-01-01

This study investigates the ERP components associated with the processing of words that are critical to generating and rejecting deductive conditional Modus Ponens arguments ("If P then Q; P//"Therefore, "Q"). The generation of a logical inference is investigated by placing a verb in the minor premise that matches the one used in the antecedent of…

ERP Correlates of Target-Distracter Differentiation in Repeated Runs of a Continuous Recognition Task with Emotional and Neutral Faces

ERIC Educational Resources Information Center

Treese, Anne-Cecile; Johansson, Mikael; Lindgren, Magnus

2010-01-01

The emotional salience of faces has previously been shown to induce memory distortions in recognition memory tasks. This event-related potential (ERP) study used repeated runs of a continuous recognition task with emotional and neutral faces to investigate emotion-induced memory distortions. In the second and third runs, participants made more…

The Processing of Consonants and Vowels during Letter Identity and Letter Position Assignment in Visual-Word Recognition: An ERP Study

ERIC Educational Resources Information Center

Vergara-Martinez, Marta; Perea, Manuel; Marin, Alejandro; Carreiras, Manuel

2011-01-01

Recent research suggests that there is a processing distinction between consonants and vowels in visual-word recognition. Here we conjointly examine the time course of consonants and vowels in processes of letter identity and letter position assignment. Event related potentials (ERPs) were recorded while participants read words and pseudowords in…