Choosing MUSE: Validation of a Low-Cost, Portable EEG System for ERP Research.

PubMed

Krigolson, Olave E; Williams, Chad C; Norton, Angela; Hassall, Cameron D; Colino, Francisco L

2017-01-01

In recent years there has been an increase in the number of portable low-cost electroencephalographic (EEG) systems available to researchers. However, to date the validation of the use of low-cost EEG systems has focused on continuous recording of EEG data and/or the replication of large system EEG setups reliant on event-markers to afford examination of event-related brain potentials (ERP). Here, we demonstrate that it is possible to conduct ERP research without being reliant on event markers using a portable MUSE EEG system and a single computer. Specifically, we report the results of two experiments using data collected with the MUSE EEG system-one using the well-known visual oddball paradigm and the other using a standard reward-learning task. Our results demonstrate that we could observe and quantify the N200 and P300 ERP components in the visual oddball task and the reward positivity (the mirror opposite component to the feedback-related negativity) in the reward-learning task. Specifically, single sample t -tests of component existence (all p 's < 0.05), computation of Bayesian credible intervals, and 95% confidence intervals all statistically verified the existence of the N200, P300, and reward positivity in all analyses. We provide with this research paper an open source website with all the instructions, methods, and software to replicate our findings and to provide researchers with an easy way to use the MUSE EEG system for ERP research. Importantly, our work highlights that with a single computer and a portable EEG system such as the MUSE one can conduct ERP research with ease thus greatly extending the possible use of the ERP methodology to a variety of novel contexts.

Increased Error-Related Negativity (ERN) in Childhood Anxiety Disorders: ERP and Source Localization

ERIC Educational Resources Information Center

Ladouceur, Cecile D.; Dahl, Ronald E.; Birmaher, Boris; Axelson, David A.; Ryan, Neal D.

2006-01-01

Background: In this study we used event-related potentials (ERPs) and source localization analyses to track the time course of neural activity underlying response monitoring in children diagnosed with an anxiety disorder compared to age-matched low-risk normal controls. Methods: High-density ERPs were examined following errors on a flanker task…

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…

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

Multiple Component Event-Related Potential (mcERP) Estimation

NASA Technical Reports Server (NTRS)

Knuth, K. H.; Clanton, S. T.; Shah, A. S.; Truccolo, W. A.; Ding, M.; Bressler, S. L.; Trejo, L. J.; Schroeder, C. E.; Clancy, Daniel (Technical Monitor)

2002-01-01

We show how model-based estimation of the neural sources responsible for transient neuroelectric signals can be improved by the analysis of single trial data. Previously, we showed that a multiple component event-related potential (mcERP) algorithm can extract the responses of individual sources from recordings of a mixture of multiple, possibly interacting, neural ensembles. McERP also estimated single-trial amplitudes and onset latencies, thus allowing more accurate estimation of ongoing neural activity during an experimental trial. The mcERP algorithm is related to informax independent component analysis (ICA); however, the underlying signal model is more physiologically realistic in that a component is modeled as a stereotypic waveshape varying both in amplitude and onset latency from trial to trial. The result is a model that reflects quantities of interest to the neuroscientist. Here we demonstrate that the mcERP algorithm provides more accurate results than more traditional methods such as factor analysis and the more recent ICA. Whereas factor analysis assumes the sources are orthogonal and ICA assumes the sources are statistically independent, the mcERP algorithm makes no such assumptions thus allowing investigators to examine interactions among components by estimating the properties of single-trial responses.

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.

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.

Estimating and Testing the Sources of Evoked Potentials in the Brain.

ERIC Educational Resources Information Center

Huizenga, Hilde M.; Molenaar, Peter C. M.

1994-01-01

The source of an event-related brain potential (ERP) is estimated from multivariate measures of ERP on the head under several mathematical and physical constraints on the parameters of the source model. Statistical aspects of estimation are discussed, and new tests are proposed. (SLD)

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.

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.

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.

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

Real-time Neuroimaging and Cognitive Monitoring Using Wearable Dry EEG

PubMed Central

Mullen, Tim R.; Kothe, Christian A.E.; Chi, Mike; Ojeda, Alejandro; Kerth, Trevor; Makeig, Scott; Jung, Tzyy-Ping; Cauwenberghs, Gert

2015-01-01

Goal We present and evaluate a wearable high-density dry electrode EEG system and an open-source software framework for online neuroimaging and state classification. Methods The system integrates a 64-channel dry EEG form-factor with wireless data streaming for online analysis. A real-time software framework is applied, including adaptive artifact rejection, cortical source localization, multivariate effective connectivity inference, data visualization, and cognitive state classification from connectivity features using a constrained logistic regression approach (ProxConn). We evaluate the system identification methods on simulated 64-channel EEG data. Then we evaluate system performance, using ProxConn and a benchmark ERP method, in classifying response errors in 9 subjects using the dry EEG system. Results Simulations yielded high accuracy (AUC=0.97±0.021) for real-time cortical connectivity estimation. Response error classification using cortical effective connectivity (sdDTF) was significantly above chance with similar performance (AUC) for cLORETA (0.74±0.09) and LCMV (0.72±0.08) source localization. Cortical ERP-based classification was equivalent to ProxConn for cLORETA (0.74±0.16) but significantly better for LCMV (0.82±0.12). Conclusion We demonstrated the feasibility for real-time cortical connectivity analysis and cognitive state classification from high-density wearable dry EEG. Significance This paper is the first validated application of these methods to 64-channel dry EEG. The work addresses a need for robust real-time measurement and interpretation of complex brain activity in the dynamic environment of the wearable setting. Such advances can have broad impact in research, medicine, and brain-computer interfaces. The pipelines are made freely available in the open-source SIFT and BCILAB toolboxes. PMID:26415149

A real-time detector system for precise timing of audiovisual stimuli.

PubMed

Henelius, Andreas; Jagadeesan, Sharman; Huotilainen, Minna

2012-01-01

The successful recording of neurophysiologic signals, such as event-related potentials (ERPs) or event-related magnetic fields (ERFs), relies on precise information of stimulus presentation times. We have developed an accurate and flexible audiovisual sensor solution operating in real-time for on-line use in both auditory and visual ERP and ERF paradigms. The sensor functions independently of the used audio or video stimulus presentation tools or signal acquisition system. The sensor solution consists of two independent sensors; one for sound and one for light. The microcontroller-based audio sensor incorporates a novel approach to the detection of natural sounds such as multipart audio stimuli, using an adjustable dead time. This aids in producing exact markers for complex auditory stimuli and reduces the number of false detections. The analog photosensor circuit detects changes in light intensity on the screen and produces a marker for changes exceeding a threshold. The microcontroller software for the audio sensor is free and open source, allowing other researchers to customise the sensor for use in specific auditory ERP/ERF paradigms. The hardware schematics and software for the audiovisual sensor are freely available from the webpage of the authors' lab.

ERP correlates of source memory: unitized source information increases familiarity-based retrieval.

PubMed

Diana, Rachel A; Van den Boom, Wijnand; Yonelinas, Andrew P; Ranganath, Charan

2011-01-07

Source memory tests typically require subjects to make decisions about the context in which an item was encoded and are thought to depend on recollection of details from the study episode. Although it is generally believed that familiarity does not contribute to source memory, recent behavioral studies have suggested that familiarity may also support source recognition when item and source information are integrated, or "unitized," during study (Diana, Yonelinas, and Ranganath, 2008). However, an alternative explanation of these behavioral findings is that unitization affects the manner in which recollection contributes to performance, rather than increasing familiarity-based source memory. To discriminate between these possibilities, we conducted an event-related potential (ERP) study testing the hypothesis that unitization increases the contribution of familiarity to source recognition. Participants studied associations between words and background colors using tasks that either encouraged or discouraged unitization. ERPs were recorded during a source memory test for background color. The results revealed two distinct neural correlates of source recognition: a frontally distributed positivity that was associated with familiarity-based source memory in the high-unitization condition only and a parietally distributed positivity that was associated with recollection-based source memory in both the high- and low-unitization conditions. The ERP and behavioral findings provide converging evidence for the idea that familiarity can contribute to source recognition, particularly when source information is encoded as an item detail. Copyright © 2010 Elsevier B.V. All rights reserved.

Implementation of the Exeter enhanced recovery programme for patients undergoing radical cystectomy.

PubMed

Dutton, Thomas J; Daugherty, Mark O; Mason, Robert G; McGrath, John S

2014-05-01

To describe our experience with the implementation and refinement of an enhanced recovery programme (ERP) for radical cystectomy (RC) and urinary diversion. To assess the impact on length of stay (LOS), complication and readmission rates. In all, 165 consecutive patients undergoing open RC (ORC) and urinary diversion between January 2008 and April 2013 were entered into an ERP. A retrospective case note review was undertaken. Outcomes recorded included LOS, time to mobilisation, complication rates within the first 30 days (Clavien-Dindo classification) and readmissions. All patients were successfully entered into the ERP. As enhanced recovery principles became embedded in the unit, LOS reduced from a mean of 14 days over the initial year of the ERP to a mean of 9.2 days. The complication rate was 6.6% for Clavien ≥3, and 43.5% for Clavien ≤2. The 30-day mortality rate was 1.2%. The 30-day readmission rate was 13.9%. In the most contemporary subset of 52 patients: the median time after ORC to sit out of bed, mobilise and open bowels was day 1, 2 and 6, respectively. The ERP described for patients undergoing ORC appears to be safe. Benefits include early feeding, mobilisation and hospital discharge. The ERP will continue to develop with the incorporation of advancing evidence and technology, in particular the introduction of robot-assisted RC. © 2013 The Authors. BJU International © 2013 BJU International.

Developmental Changes in Item and Source Memory: Evidence from an ERP Recognition Memory Study with Children, Adolescents, and Adults

ERIC Educational Resources Information Center

Sprondel, Volker; Kipp, Kerstin H.; Mecklinger, Axel

2011-01-01

Event-related potential (ERP) correlates of item and source memory were assessed in 18 children (7-8 years), 20 adolescents (13-14 years), and 20 adults (20-29 years) performing a continuous recognition memory task with object and nonobject stimuli. Memory performance increased with age and was particularly low for source memory in children. The…

Pursuing a Vendor-Endorsed ERP Award for Better Job Prospect: Students' Perceptions

ERIC Educational Resources Information Center

Kung, LeeAnn; Kung, Hsiang-Jui

2017-01-01

This paper identifies factors that motivate students to pursue a vendor-endorsed ERP award by integrating concepts from motivation theory and constructs from technology acceptance literature. We developed a web-based survey with closed- and open-ended questions to collect both quantitative and qualitative data, respectively. Students in…

Open Innovation and the Erosion of the Traditional Information Systems Project's Boundaries

NASA Astrophysics Data System (ADS)

Elbanna, Amany

This paper examines the notion of open innovation and its implication on information systems management. It investigates a project of an enterprise resource planning system implementation in an international organization to unravel the resemblance with the open innovation model. The study shows that the conceptualization of ERP project as an open innovation could reveal the complex architecture of today's organization from which the ERP project cannot be isolated. It argues that the traditional boundaries around IS projects are dissolving and the relationship between what used to be outside and what used to be inside the project is increasingly blurred. The study calls for a different perspective of project management that goes beyond single and multiple project management to scan the open space of innovation and actively look for partners, competitors, and collaborators.

ERP denoising in multichannel EEG data using contrasts between signal and noise subspaces.

PubMed

Ivannikov, Andriy; Kalyakin, Igor; Hämäläinen, Jarmo; Leppänen, Paavo H T; Ristaniemi, Tapani; Lyytinen, Heikki; Kärkkäinen, Tommi

2009-06-15

In this paper, a new method intended for ERP denoising in multichannel EEG data is discussed. The denoising is done by separating ERP/noise subspaces in multidimensional EEG data by a linear transformation and the following dimension reduction by ignoring noise components during inverse transformation. The separation matrix is found based on the assumption that ERP sources are deterministic for all repetitions of the same type of stimulus within the experiment, while the other noise sources do not obey the determinancy property. A detailed derivation of the technique is given together with the analysis of the results of its application to a real high-density EEG data set. The interpretation of the results and the performance of the proposed method under conditions, when the basic assumptions are violated - e.g. the problem is underdetermined - are also discussed. Moreover, we study how the factors of the number of channels and trials used by the method influence the effectiveness of ERP/noise subspaces separation. In addition, we explore also the impact of different data resampling strategies on the performance of the considered algorithm. The results can help in determining the optimal parameters of the equipment/methods used to elicit and reliably estimate ERPs.

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.

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

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.

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.

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…

Perceptual reversals during binocular rivalry: ERP components and their concomitant source differences.

PubMed

Britz, Juliane; Pitts, Michael A

2011-11-01

We used an intermittent stimulus presentation to investigate event-related potential (ERP) components associated with perceptual reversals during binocular rivalry. The combination of spatiotemporal ERP analysis with source imaging and statistical parametric mapping of the concomitant source differences yielded differences in three time windows: reversals showed increased activity in early visual (∼120 ms) and in inferior frontal and anterior temporal areas (∼400-600 ms) and decreased activity in the ventral stream (∼250-350 ms). The combination of source imaging and statistical parametric mapping suggests that these differences were due to differences in generator strength and not generator configuration, unlike the initiation of reversals in right inferior parietal areas. These results are discussed within the context of the extensive network of brain areas that has been implicated in the initiation, implementation, and appraisal of bistable perceptual reversals. Copyright © 2011 Society for Psychophysiological Research.

The influence of directed attention at encoding on source memory retrieval in the young and old: an ERP study.

PubMed

Dulas, Michael R; Duarte, Audrey

2013-03-15

Neuroimaging evidence suggests that older adults exhibit deficits in frontally-mediated strategic retrieval processes, such as post-retrieval monitoring. Behavioral research suggests that explicitly directing attention toward source features during encoding may improve source memory for both young and older adults and alleviate age-related source memory impairments, in part, by reducing demands on post-retrieval monitoring. We investigated this hypothesis in the present event-related potential (ERP) study. Young and older adults attended to either objects and their presented color (source) or to the object alone during study and made color source memory decisions at test. We attempted to match performance between groups by halving the memory load for older adults. Behavioral results showed that, while direction of attention to object and color improved source memory for both groups, older adults benefited less than the young. ERPs revealed that demands on late right frontal effects, indicative of post-retrieval monitoring, were similarly reduced by directed attention at encoding for both groups. However, older adults showed reduced ERP correlates of recollection (parietal old-new effect), as well as a sustained widespread negativity, potentially indicative of memory searches for perceptual details in the face of impaired recollection. These results suggest that older adults, like the young, can engage in post-retrieval monitoring when source details are difficult to recover. However, impaired recollection may underlie persistent age-related source memory deficits, even when encoding is supported via directed attention. Copyright © 2013 Elsevier B.V. All rights reserved.

The sensory timecourses associated with conscious visual item memory and source memory.

PubMed

Thakral, Preston P; Slotnick, Scott D

2015-09-01

Previous event-related potential (ERP) findings have suggested that during visual item and source memory, nonconscious and conscious sensory (occipital-temporal) activity onsets may be restricted to early (0-800 ms) and late (800-1600 ms) temporal epochs, respectively. In an ERP experiment, we tested this hypothesis by separately assessing whether the onset of conscious sensory activity was restricted to the late epoch during source (location) memory and item (shape) memory. We found that conscious sensory activity had a late (>800 ms) onset during source memory and an early (<200 ms) onset during item memory. In a follow-up fMRI experiment, conscious sensory activity was localized to BA17, BA18, and BA19. Of primary importance, the distinct source memory and item memory ERP onsets contradict the hypothesis that there is a fixed temporal boundary separating nonconscious and conscious processing during all forms of visual conscious retrieval. Copyright © 2015 Elsevier B.V. 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.

Differentiating weak ties and strong ties among external sources of influences for enterprise resource planning (ERP) adoption

NASA Astrophysics Data System (ADS)

Aubert, Benoit; Léger, Pierre-Majorique; Larocque, Denis

2012-05-01

Enterprise resource planning (ERP) systems represent a major IT adoption decision. ERP adoption decisions, in the chemicals and allied products sectors, were examined between 1994 and 2005. Networks of strong ties and weak ties partners are investigated. Results show that neighbouring companies linked with strong ties can have an influence on organisations making such adoption decision. Past decisions made by major trading partners have a significant influence on the decision to adopt an ERP system for a given organisation. This reflects the complex nature of the knowledge required for such adoption.

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.

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

Analysis of earth rotation solution from Starlette

NASA Technical Reports Server (NTRS)

Schutz, B. E.; Cheng, M. K.; Shum, C. K.; Eanes, R. J.; Tapley, B. D.

1989-01-01

Earth rotation parameter (ERP) solutions were derived from the Starlette orbit analysis during the Main MERIT Campaign, using a technique of a consider-covariance analysis to assess the effects of errors on the polar motion solutions. The polar motion solution was then improved through the simultaneous adjustment of some dynamical parameters representing identified dominant perturbing sources (such as the geopotential and ocean-tide coefficients) on the polar motion solutions. Finally, an improved ERP solution was derived using the gravity field model, PTCF1, described by Tapley et al. (1986). The accuracy of the Starlette ERP solution was assessed by a comparison with the LAGEOS-derived ERP solutions.

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.

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.

Electrophysiological Correlates of Emotional Source Memory in High-Trait-Anxiety Individuals

PubMed Central

Cui, Lixia; Shi, Guangyuan; He, Fan; Zhang, Qin; Oei, Tian P. S.; Guo, Chunyan

2016-01-01

The interaction between recognition memory and emotion has become a research hotspot in recent years. Dual process theory posits that familiarity and recollection are two separate processes contributing to recognition memory, but further experimental evidence is needed. The present study explored the emotional context effects on successful and unsuccessful source retrieval amongst 15 high-trait-anxiety college students by using event-related potentials (ERPs) measurement. During study, a happy, fearful, or neutral face picture first was displayed, then a Chinese word was superimposed centrally on the picture and subjects were asked to remember the word and the corresponding type of picture. During the test participants were instructed to press one of four buttons to indicate whether the displayed word was an old or new word. And then, for the old word, indicate whether it had been shown with a fearful, happy, or neutral face during the study. ERPs were generally more positive for remembered words than for new words and the ERP difference was termed as an old/new effect. It was found that, for successful source retrieval (it meant both the item and the source were remembered accurately) between 500 and 700 ms (corresponding to a late positive component, LPC), there were significant old/new effects in all contexts. However, for unsuccessful source retrieval (it meant the correct recognition of old items matched with incorrect source attribution), there were no significant old/new effects in happy and neutral contexts, though significant old/new effects were observed in the fearful context. Between 700 and 1200 ms (corresponding to a late slow wave, LSW), there were significant old/new effects for successful source retrieval in happy and neutral contexts. However, in the fearful context, the old/new effects were reversed, ERPs were more negative for successful source retrieval compared to correct rejections. Moreover, there were significant emotion effects for successful source retrieval at this time window. Further analysis showed ERPs of old items were more negative in fearful context than in neutral context. The results showed that early unsuccessful fearful source retrieval processes (related to familiarity) were enhanced, but late successful fearful source retrieval processes during source retrieval monitoring (related to recollection) were weakened. This provided preliminary evidence for the dual processing theory. PMID:27462288

Dissociable effects of reward and expectancy during evaluative feedback processing revealed by topographic ERP mapping analysis.

PubMed

Gheza, Davide; Paul, Katharina; Pourtois, Gilles

2017-11-24

Evaluative feedback provided during performance monitoring (PM) elicits either a positive or negative deflection ~250-300ms after its onset in the event-related potential (ERP) depending on whether the outcome is reward-related or not, as well as expected or not. However, it remains currently unclear whether these two deflections reflect a unitary process, or rather dissociable effects arising from non-overlapping brain networks. To address this question, we recorded 64-channel EEG in healthy adult participants performing a standard gambling task where valence and expectancy were manipulated in a factorial design. We analyzed the feedback-locked ERP data using a conventional ERP analysis, as well as an advanced topographic ERP mapping analysis supplemented with distributed source localization. Results reveal two main topographies showing opposing valence effects, and being differently modulated by expectancy. The first one was short-lived and sensitive to no-reward irrespective of expectancy. Source-estimation associated with this topographic map comprised mainly regions of the dorsal anterior cingulate cortex. The second one was primarily driven by reward, had a prolonged time-course and was monotonically influenced by expectancy. Moreover, this reward-related topographical map was best accounted for by intracranial generators estimated in the posterior cingulate cortex. These new findings suggest the existence of dissociable brain systems depending on feedback valence and expectancy. More generally, they inform about the added value of using topographic ERP mapping methods, besides conventional ERP measurements, to characterize qualitative changes occurring in the spatio-temporal dynamic of reward processing during PM. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Crystal Structure of the ERp44-Peroxiredoxin 4 Complex Reveals the Molecular Mechanisms of Thiol-Mediated Protein Retention.

PubMed

Yang, Kai; Li, De-Feng; Wang, Xi'e; Liang, Jinzhao; Sitia, Roberto; Wang, Chih-Chen; Wang, Xi

2016-10-04

ERp44 controls the localization and transport of diverse proteins in the early secretory pathway. The mechanisms that allow client recognition and the source of the oxidative power for forming intermolecular disulfides are as yet unknown. Here we present the structure of ERp44 bound to a client, peroxiredoxin 4. Our data reveal that ERp44 binds the oxidized form of peroxiredoxin 4 via thiol-disulfide interchange reactions. The structure explains the redox-dependent recognition and characterizes the essential non-covalent interactions at the interface. The ERp44-Prx4 covalent complexes can be reduced by glutathione and protein disulfide isomerase family members in the ER, allowing the two components to recycle. This work provides insights into the mechanisms of thiol-mediated protein retention and indicates the key roles of ERp44 in this biochemical cycle to optimize oxidative folding and redox homeostasis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recording event-related activity under hostile magnetic resonance environment: Is multimodal EEG/ERP-MRI recording possible?

PubMed

Karakaş, H M; Karakaş, S; Ozkan Ceylan, A; Tali, E T

2009-08-01

Event-related potentials (ERPs) have high temporal resolution, but insufficient spatial resolution; the converse is true for the functional imaging techniques. The purpose of the study was to test the utility of a multimodal EEG/ERP-MRI technique which combines electroencephalography (EEG) and magnetic resonance imaging (MRI) for a simultaneously high temporal and spatial resolution. The sample consisted of 32 healthy young adults of both sexes. Auditory stimuli were delivered according to the active and passive oddball paradigms in the MRI environment (MRI-e) and in the standard conditions of the electrophysiology laboratory environment (Lab-e). Tasks were presented in a fixed order. Participants were exposed to the recording environments in a counterbalanced order. EEG data were preprocessed for MRI-related artifacts. Source localization was made using a current density reconstruction technique. The ERP waveforms for the MRI-e were morphologically similar to those for the Lab-e. The effect of the recording environment, experimental paradigm and electrode location were analyzed using a 2x2x3 analysis of variance for repeated measures. The ERP components in the two environments showed parametric variations and characteristic topographical distributions. The calculated sources were in line with the related literature. The findings indicated effortful cognitive processing in MRI-e. The study provided preliminary data on the feasibility of the multimodal EEG/ERP-MRI technique. It also indicated lines of research that are to be pursued for a decisive testing of this technique and its implementation to clinical practice.

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.

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.

Spatiotemporal mapping of sex differences during attentional processing.

PubMed

Neuhaus, Andres H; Opgen-Rhein, Carolin; Urbanek, Carsten; Gross, Melanie; Hahn, Eric; Ta, Thi Minh Tam; Koehler, Simone; Dettling, Michael

2009-09-01

Functional neuroimaging studies have increasingly aimed at approximating neural substrates of human cognitive sex differences elicited by visuospatial challenge. It has been suggested that females and males use different behaviorally relevant neurocognitive strategies. In females, greater right prefrontal cortex activation has been found in several studies. The spatiotemporal dynamics of neural events associated with these sex differences is still unclear. We studied 22 female and 22 male participants matched for age, education, and nicotine with 29-channel-electroencephalogram recorded under a visual selective attention paradigm, the Attention Network Test. Visual event-related potentials (ERP) were topographically analyzed and neuroelectric sources were estimated. In absence of behavioral differences, ERP analysis revealed a novel frontal-occipital second peak of visual N100 that was significantly increased in females relative to males. Further, in females exclusively, a corresponding central ERP component at around 220 ms was found; here, a strong correlation between stimulus salience and sex difference of the central ERP component amplitude was observed. Subsequent source analysis revealed increased cortical current densities in right rostral prefrontal (BA 10) and occipital cortex (BA 19) in female subjects. This is the first study to report on a tripartite association between sex differences in ERPs, visual stimulus salience, and right prefrontal cortex activation during attentional processing. 2009 Wiley-Liss, Inc.

Implicit Processing of the Eyes and Mouth: Evidence from Human Electrophysiology.

PubMed

Pesciarelli, Francesca; Leo, Irene; Sarlo, Michela

2016-01-01

The current study examined the time course of implicit processing of distinct facial features and the associate event-related potential (ERP) components. To this end, we used a masked priming paradigm to investigate implicit processing of the eyes and mouth in upright and inverted faces, using a prime duration of 33 ms. Two types of prime-target pairs were used: 1. congruent (e.g., open eyes only in both prime and target or open mouth only in both prime and target); 2. incongruent (e.g., open mouth only in prime and open eyes only in target or open eyes only in prime and open mouth only in target). The identity of the faces changed between prime and target. Participants pressed a button when the target face had the eyes open and another button when the target face had the mouth open. The behavioral results showed faster RTs for the eyes in upright faces than the eyes in inverted faces, the mouth in upright and inverted faces. Moreover they also revealed a congruent priming effect for the mouth in upright faces. The ERP findings showed a face orientation effect across all ERP components studied (P1, N1, N170, P2, N2, P3) starting at about 80 ms, and a congruency/priming effect on late components (P2, N2, P3), starting at about 150 ms. Crucially, the results showed that the orientation effect was driven by the eye region (N170, P2) and that the congruency effect started earlier (P2) for the eyes than for the mouth (N2). These findings mark the time course of the processing of internal facial features and provide further evidence that the eyes are automatically processed and that they are very salient facial features that strongly affect the amplitude, latency, and distribution of neural responses to faces.

Implicit Processing of the Eyes and Mouth: Evidence from Human Electrophysiology

PubMed Central

Pesciarelli, Francesca; Leo, Irene; Sarlo, Michela

2016-01-01

The current study examined the time course of implicit processing of distinct facial features and the associate event-related potential (ERP) components. To this end, we used a masked priming paradigm to investigate implicit processing of the eyes and mouth in upright and inverted faces, using a prime duration of 33 ms. Two types of prime-target pairs were used: 1. congruent (e.g., open eyes only in both prime and target or open mouth only in both prime and target); 2. incongruent (e.g., open mouth only in prime and open eyes only in target or open eyes only in prime and open mouth only in target). The identity of the faces changed between prime and target. Participants pressed a button when the target face had the eyes open and another button when the target face had the mouth open. The behavioral results showed faster RTs for the eyes in upright faces than the eyes in inverted faces, the mouth in upright and inverted faces. Moreover they also revealed a congruent priming effect for the mouth in upright faces. The ERP findings showed a face orientation effect across all ERP components studied (P1, N1, N170, P2, N2, P3) starting at about 80 ms, and a congruency/priming effect on late components (P2, N2, P3), starting at about 150 ms. Crucially, the results showed that the orientation effect was driven by the eye region (N170, P2) and that the congruency effect started earlier (P2) for the eyes than for the mouth (N2). These findings mark the time course of the processing of internal facial features and provide further evidence that the eyes are automatically processed and that they are very salient facial features that strongly affect the amplitude, latency, and distribution of neural responses to faces. PMID:26790153

App-guided exposure and response prevention for obsessive compulsive disorder: an open pilot trial.

PubMed

Boisseau, Christina L; Schwartzman, Carly M; Lawton, Jessica; Mancebo, Maria C

2017-11-01

Although effective treatments for obsessive-compulsive disorder (OCD) exist, there are significant barriers to receiving evidence-based care. Mobile health applications (Apps) offer a promising way of overcoming these barriers by increasing access to treatment. The current study investigated the feasibility, acceptability, and preliminary efficacy of LiveOCDFree, an App designed to help OCD patients conduct exposure and response prevention (ERP). Twenty-one participants with mild to moderate symptoms of OCD were enrolled in a 12-week open trial of App-guided self-help ERP. Self-report assessments of OCD, depression, anxiety, and quality of life were completed at baseline, mid-treatment, and post-treatment. App-guided ERP was a feasible and acceptable self-help intervention for individuals with OCD, with high rates of retention and satisfaction. Participants reported significant improvement in OCD and anxiety symptoms pre- to post-treatment. Findings suggest that LiveOCDFree is a feasible and acceptable self-help intervention for OCD. Preliminary efficacy results are encouraging and point to the potential utility of mobile Apps in expanding the reach of existing empirically supported treatments.

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.

adLIMS: a customized open source software that allows bridging clinical and basic molecular research studies.

PubMed

Calabria, Andrea; Spinozzi, Giulio; Benedicenti, Fabrizio; Tenderini, Erika; Montini, Eugenio

2015-01-01

Many biological laboratories that deal with genomic samples are facing the problem of sample tracking, both for pure laboratory management and for efficiency. Our laboratory exploits PCR techniques and Next Generation Sequencing (NGS) methods to perform high-throughput integration site monitoring in different clinical trials and scientific projects. Because of the huge amount of samples that we process every year, which result in hundreds of millions of sequencing reads, we need to standardize data management and tracking systems, building up a scalable and flexible structure with web-based interfaces, which are usually called Laboratory Information Management System (LIMS). We started collecting end-users' requirements, composed of desired functionalities of the system and Graphical User Interfaces (GUI), and then we evaluated available tools that could address our requirements, spanning from pure LIMS to Content Management Systems (CMS) up to enterprise information systems. Our analysis identified ADempiere ERP, an open source Enterprise Resource Planning written in Java J2EE, as the best software that also natively implements some highly desirable technological advances, such as the high usability and modularity that grants high use-case flexibility and software scalability for custom solutions. We extended and customized ADempiere ERP to fulfil LIMS requirements and we developed adLIMS. It has been validated by our end-users verifying functionalities and GUIs through test cases for PCRs samples and pre-sequencing data and it is currently in use in our laboratories. adLIMS implements authorization and authentication policies, allowing multiple users management and roles definition that enables specific permissions, operations and data views to each user. For example, adLIMS allows creating sample sheets from stored data using available exporting operations. This simplicity and process standardization may avoid manual errors and information backtracking, features that are not granted using track recording on files or spreadsheets. adLIMS aims to combine sample tracking and data reporting features with higher accessibility and usability of GUIs, thus allowing time to be saved on doing repetitive laboratory tasks, and reducing errors with respect to manual data collection methods. Moreover, adLIMS implements automated data entry, exploiting sample data multiplexing and parallel/transactional processing. adLIMS is natively extensible to cope with laboratory automation through platform-dependent API interfaces, and could be extended to genomic facilities due to the ERP functionalities.

Applying an Archetype-Based Approach to Electroencephalography/Event-Related Potential Experiments in the EEGBase Resource.

PubMed

Papež, Václav; Mouček, Roman

2017-01-01

The purpose of this study is to investigate the feasibility of applying openEHR (an archetype-based approach for electronic health records representation) to modeling data stored in EEGBase, a portal for experimental electroencephalography/event-related potential (EEG/ERP) data management. The study evaluates re-usage of existing openEHR archetypes and proposes a set of new archetypes together with the openEHR templates covering the domain. The main goals of the study are to (i) link existing EEGBase data/metadata and openEHR archetype structures and (ii) propose a new openEHR archetype set describing the EEG/ERP domain since this set of archetypes currently does not exist in public repositories. The main methodology is based on the determination of the concepts obtained from EEGBase experimental data and metadata that are expressible structurally by the openEHR reference model and semantically by openEHR archetypes. In addition, templates as the third openEHR resource allow us to define constraints over archetypes. Clinical Knowledge Manager (CKM), a public openEHR archetype repository, was searched for the archetypes matching the determined concepts. According to the search results, the archetypes already existing in CKM were applied and the archetypes not existing in the CKM were newly developed. openEHR archetypes support linkage to external terminologies. To increase semantic interoperability of the new archetypes, binding with the existing odML electrophysiological terminology was assured. Further, to increase structural interoperability, also other current solutions besides EEGBase were considered during the development phase. Finally, a set of templates using the selected archetypes was created to meet EEGBase requirements. A set of eleven archetypes that encompassed the domain of experimental EEG/ERP measurements were identified. Of these, six were reused without changes, one was extended, and four were newly created. All archetypes were arranged in the templates reflecting the EEGBase metadata structure. A mechanism of odML terminology referencing was proposed to assure semantic interoperability of the archetypes. The openEHR approach was found to be useful not only for clinical purposes but also for experimental data modeling.

The development of control processes supporting source memory discrimination as revealed by event-related potentials.

PubMed

de Chastelaine, Marianne; Friedman, David; Cycowicz, Yael M

2007-08-01

Improvement in source memory performance throughout childhood is thought to be mediated by the development of executive control. As postretrieval control processes may be better time-locked to the recognition response rather than the retrieval cue, the development of processes underlying source memory was investigated with both stimulus- and response-locked event-related potentials (ERPs). These were recorded in children, adolescents, and adults during a recognition memory exclusion task. Green- and red-outlined pictures were studied, but were tested in black outline. The test requirement was to endorse old items shown in one study color ("targets") and to reject new items along with old items shown in the alternative study color ("nontargets"). Source memory improved with age. All age groups retrieved target and nontarget memories as reflected by reliable parietal episodic memory (EM) effects, a stimulus-locked ERP correlate of recollection. Response-locked ERPs to targets and nontargets diverged in all groups prior to the response, although this occurred at an increasingly earlier time point with age. We suggest these findings reflect the implementation of attentional control mechanisms to enhance target memories and facilitate response selection with the greatest and least success, respectively, in adults and children. In adults only, response-locked ERPs revealed an early-onsetting parietal negativity for nontargets, but not for targets. This was suggested to reflect adults' ability to consistently inhibit prepotent target responses for nontargets. The findings support the notion that the development of source memory relies on the maturation of control processes that serve to enhance accurate selection of task-relevant memories.

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.

ERPs recorded during early second language exposure predict syntactic learning.

PubMed

Batterink, Laura; Neville, Helen J

2014-09-01

Millions of adults worldwide are faced with the task of learning a second language (L2). Understanding the neural mechanisms that support this learning process is an important area of scientific inquiry. However, most previous studies on the neural mechanisms underlying L2 acquisition have focused on characterizing the results of learning, relying upon end-state outcome measures in which learning is assessed after it has occurred, rather than on the learning process itself. In this study, we adopted a novel and more direct approach to investigate neural mechanisms engaged during L2 learning, in which we recorded ERPs from beginning adult learners as they were exposed to an unfamiliar L2 for the first time. Learners' proficiency in the L2 was then assessed behaviorally using a grammaticality judgment task, and ERP data acquired during initial L2 exposure were sorted as a function of performance on this task. High-proficiency learners showed a larger N100 effect to open-class content words compared with closed-class function words, whereas low-proficiency learners did not show a significant N100 difference between open- and closed-class words. In contrast, amplitude of the N400 word category effect correlated with learners' L2 comprehension, rather than predicting syntactic learning. Taken together, these results indicate that learners who spontaneously direct greater attention to open- rather than closed-class words when processing L2 input show better syntactic learning, suggesting a link between selective attention to open-class content words and acquisition of basic morphosyntactic rules. These findings highlight the importance of selective attention mechanisms for L2 acquisition.

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.

Frontal midline theta and the error-related negativity: neurophysiological mechanisms of action regulation.

PubMed

Luu, Phan; Tucker, Don M; Makeig, Scott

2004-08-01

The error-related negativity (ERN) is an event-related potential (ERP) peak occurring between 50 and 100 ms after the commission of a speeded motor response that the subject immediately realizes to be in error. The ERN is believed to index brain processes that monitor action outcomes. Our previous analyses of ERP and EEG data suggested that the ERN is dominated by partial phase-locking of intermittent theta-band EEG activity. In this paper, this possibility is further evaluated. The possibility that the ERN is produced by phase-locking of theta-band EEG activity was examined by analyzing the single-trial EEG traces from a forced-choice speeded response paradigm before and after applying theta-band (4-7 Hz) filtering and by comparing the averaged and single-trial phase-locked (ERP) and non-phase-locked (other) EEG data. Electrical source analyses were used to estimate the brain sources involved in the generation of the ERN. Beginning just before incorrect button presses in a speeded choice response paradigm, midfrontal theta-band activity increased in amplitude and became partially and transiently phase-locked to the subject's motor response, accounting for 57% of ERN peak amplitude. The portion of the theta-EEG activity increase remaining after subtracting the response-locked ERP from each trial was larger and longer lasting after error responses than after correct responses, extending on average 400 ms beyond the ERN peak. Multiple equivalent-dipole source analysis suggested 3 possible equivalent dipole sources of the theta-bandpassed ERN, while the scalp distribution of non-phase-locked theta amplitude suggested the presence of additional frontal theta-EEG sources. These results appear consistent with a body of research that demonstrates a relationship between limbic theta activity and action regulation, including error monitoring and learning.

Cortical sources of ERP in prosaccade and antisaccade eye movements using realistic source models

PubMed Central

Richards, John E.

2013-01-01

The cortical sources of event-related-potentials (ERP) using realistic source models were examined in a prosaccade and antisaccade procedure. College-age participants were presented with a preparatory interval and a target that indicated the direction of the eye movement that was to be made. In some blocks a cue was given in the peripheral location where the target was to be presented and in other blocks no cue was given. In Experiment 1 the prosaccade and antisaccade trials were presented randomly within a block; in Experiment 2 procedures were compared in which either prosaccade and antisaccade trials were mixed in the same block, or trials were presented in separate blocks with only one type of eye movement. There was a central negative slow wave occurring prior to the target, a slow positive wave over the parietal scalp prior to the saccade, and a parietal spike potential immediately prior to saccade onset. Cortical source analysis of these ERP components showed a common set of sources in the ventral anterior cingulate and orbital frontal gyrus for the presaccadic positive slow wave and the spike potential. In Experiment 2 the same cued- and non-cued blocks were used, but prosaccade and antisaccade trials were presented in separate blocks. This resulted in a smaller difference in reaction time between prosaccade and antisaccade trials. Unlike the first experiment, the central negative slow wave was larger on antisaccade than on prosaccade trials, and this effect on the ERP component had its cortical source primarily in the parietal and mid-central cortical areas contralateral to the direction of the eye movement. These results suggest that blocked prosaccade and antisaccade trials results in preparatory or set effects that decreases reaction time, eliminates some cueing effects, and is based on contralateral parietal-central brain areas. PMID:23847476

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.

Cortical Neural Synchronization Underlies Primary Visual Consciousness of Qualia: Evidence from Event-Related Potentials

PubMed Central

Babiloni, Claudio; Marzano, Nicola; Soricelli, Andrea; Cordone, Susanna; Millán-Calenti, José Carlos; Del Percio, Claudio; Buján, Ana

2016-01-01

This article reviews three experiments on event-related potentials (ERPs) testing the hypothesis that primary visual consciousness (stimulus self-report) is related to enhanced cortical neural synchronization as a function of stimulus features. ERP peak latency and sources were compared between “seen” trials and “not seen” trials, respectively related and unrelated to the primary visual consciousness. Three salient features of visual stimuli were considered (visuospatial, emotional face expression, and written words). Results showed the typical visual ERP components in both “seen” and “not seen” trials. There was no statistical difference in the ERP peak latencies between the “seen” and “not seen” trials, suggesting a similar timing of the cortical neural synchronization regardless the primary visual consciousness. In contrast, ERP sources showed differences between “seen” and “not seen” trials. For the visuospatial stimuli, the primary consciousness was related to higher activity in dorsal occipital and parietal sources at about 400 ms post-stimulus. For the emotional face expressions, there was greater activity in parietal and frontal sources at about 180 ms post-stimulus. For the written letters, there was higher activity in occipital, parietal and temporal sources at about 230 ms post-stimulus. These results hint that primary visual consciousness is associated with an enhanced cortical neural synchronization having entirely different spatiotemporal characteristics as a function of the features of the visual stimuli and possibly, the relative qualia (i.e., visuospatial, face expression, and words). In this framework, the dorsal visual stream may be synchronized in association with the primary consciousness of visuospatial and emotional face contents. Analogously, both dorsal and ventral visual streams may be synchronized in association with the primary consciousness of linguistic contents. In this line of reasoning, the ensemble of the cortical neural networks underpinning the single visual features would constitute a sort of multi-dimensional palette of colors, shapes, regions of the visual field, movements, emotional face expressions, and words. The synchronization of one or more of these cortical neural networks, each with its peculiar timing, would produce the primary consciousness of one or more of the visual features of the scene. PMID:27445750

The Basal Ganglia Striosomes Affect the Modulation of Conflicts by Subliminal Information-Evidence from X-Linked Dystonia Parkinsonism.

PubMed

Beste, Christian; Mückschel, Moritz; Rosales, Raymond; Domingo, Aloysius; Lee, Lillian; Ng, Arlene; Klein, Christine; Münchau, Alexander

2018-07-01

Cognitive control is relevant when distracting information induces behavioral conflicts. Such conflicts can be produced consciously and by subliminally processed information. Interestingly, both sources of conflict interact suggesting that they share neural mechanisms. Here, we ask whether conjoint effects between different sources of conflict are modulated by microstructural basal ganglia dysfunction. To this end, we carried out an electroencephalography study and examined event-related potentials (ERPs) including source localization using a combined flanker-subliminal priming task in patients with X-linked dystonia Parkinsonism (XDP) and a group of healthy controls. XDP in its early stages is known to predominantly affect the basal ganglia striosomes. The results suggest that conjoint effects between subliminal and conscious sources of conflicts are modulated by the striosomes and were stronger in XDP patients. The neurophysiological data indicate that this effect is related to modulations in conflict monitoring and response selection (N2 ERP) mechanisms engaging the anterior cingulate cortex. Bottom-up perceptual gating, attentional selection, and motor response activation processes in response to the stimuli (P1, N1, and lateralized readiness potential ERPs) were unaffected. Taken together, these data indicate that striosomes modulate the processing of conscious and subliminal sources of conflict suggesting that microstructural basal ganglia properties are relevant for cognitive control.

Infant Attention and Visual Preferences: Converging Evidence from Behavior, Event-Related Potentials, and Cortical Source Localization

ERIC Educational Resources Information Center

Reynolds, Greg D.; Courage, Mary L.; Richards, John E.

2010-01-01

In this study, we had 3 major goals. The 1st goal was to establish a link between behavioral and event-related potential (ERP) measures of infant attention and recognition memory. To assess the distribution of infant visual preferences throughout ERP testing, we designed a new experimental procedure that embeds a behavioral measure (paired…

The relationship between somatic and cognitive-affective depression symptoms and error-related ERPs.

PubMed

Bridwell, David A; Steele, Vaughn R; Maurer, J Michael; Kiehl, Kent A; Calhoun, Vince D

2015-02-01

The symptoms that contribute to the clinical diagnosis of depression likely emerge from, or are related to, underlying cognitive deficits. To understand this relationship further, we examined the relationship between self-reported somatic and cognitive-affective Beck'sDepression Inventory-II (BDI-II) symptoms and aspects of cognitive control reflected in error event-related potential (ERP) responses. Task and assessment data were analyzed within 51 individuals. The group contained a broad distribution of depressive symptoms, as assessed by BDI-II scores. ERPs were collected following error responses within a go/no-go task. Individual error ERP amplitudes were estimated by conducting group independent component analysis (ICA) on the electroencephalographic (EEG) time series and analyzing the individual reconstructed source epochs. Source error amplitudes were correlated with the subset of BDI-II scores representing somatic and cognitive-affective symptoms. We demonstrate a negative relationship between somatic depression symptoms (i.e. fatigue or loss of energy) (after regressing out cognitive-affective scores, age and IQ) and the central-parietal ERP response that peaks at 359 ms. The peak amplitudes within this ERP response were not significantly related to cognitive-affective symptom severity (after regressing out the somatic symptom scores, age, and IQ). These findings were obtained within a population of female adults from a maximum-security correctional facility. Thus, additional research is required to verify that they generalize to the broad population. These results suggest that individuals with greater somatic depression symptoms demonstrate a reduced awareness of behavioral errors, and help clarify the relationship between clinical measures of self-reported depression symptoms and cognitive control. Copyright © 2014 Elsevier B.V. All rights reserved.

An event-related potential study of memory for words spoken aloud or heard.

PubMed

Wilding, E L; Rugg, M D

1997-09-01

Subjects made old/new recognition judgements to visually presented words, half of which had been encountered in a prior study phase. For each word judged old, subjects made a subsequent source judgement, indicating whether they had pronounced the word aloud at study (spoken words), or whether they had heard the word spoken to them (heard words). Event-related potentials (ERPs) were compared for three classes of test item; words correctly judged to be new (correct rejections), and spoken and heard words that were correctly assigned to source (spoken hit/hit and heard hit/hit response categories). Consistent with previous findings (Wilding, E. L. and Rugg, M. D., Brain, 1996, 119, 889-905), two temporally and topographically dissociable components, with parietal and frontal maxima respectively, differentiated the ERPs to the hit/hit and correct rejection response categories. In addition, there was some evidence that the frontally distributed component could be decomposed into two distinct components, only one of which differentiated the two classes of hit/hit ERPs. The findings suggest that at least three functionally and neurologically dissociable processes can contribute to successful recovery of source information.

The effects of aging on ERP correlates of source memory retrieval for self-referential information.

PubMed

Dulas, Michael R; Newsome, Rachel N; Duarte, Audrey

2011-03-04

Numerous behavioral studies have suggested that normal aging negatively affects source memory accuracy for various kinds of associations. Neuroimaging evidence suggests that less efficient retrieval processing (temporally delayed and attenuated) may contribute to these impairments. Previous aging studies have not compared source memory accuracy and corresponding neural activity for different kinds of source details; namely, those that have been encoded via a more or less effective strategy. Thus, it is not yet known whether encoding source details in a self-referential manner, a strategy suggested to promote successful memory in the young and old, may enhance source memory accuracy and reduce the commonly observed age-related changes in neural activity associated with source memory retrieval. Here, we investigated these issues by using event-related potentials (ERPs) to measure the effects of aging on the neural correlates of successful source memory retrieval ("old-new effects") for objects encoded either self-referentially or self-externally. Behavioral results showed that both young and older adults demonstrated better source memory accuracy for objects encoded self-referentially. ERP results showed that old-new effects onsetted earlier for self-referentially encoded items in both groups and that age-related differences in the onset latency of these effects were reduced for self-referentially, compared to self-externally, encoded items. These results suggest that the implementation of an effective encoding strategy, like self-referential processing, may lead to more efficient retrieval, which in turn may improve source memory accuracy in both young and older adults. Published by Elsevier B.V.

Progressive quality control of secretory proteins in the early secretory compartment by ERp44

PubMed Central

Sannino, Sara; Anelli, Tiziana; Cortini, Margherita; Masui, Shoji; Degano, Massimo; Fagioli, Claudio; Inaba, Kenji; Sitia, Roberto

2014-01-01

ERp44 is a pH-regulated chaperone of the secretory pathway. In the acidic milieu of the Golgi, its C-terminal tail changes conformation, simultaneously exposing the substrate-binding site for cargo capture and the RDEL motif for ER retrieval via interactions with cognate receptors. Protonation of cysteine 29 in the active site allows tail movements in vitro and in vivo. Here we show that also conserved histidines in the C-terminal tail regulate ERp44 in vivo. Mutants lacking these histidines are hyperactive in retaining substrates. Surprisingly, they are also O-glycosylated and partially secreted. Co-expression of client proteins prevents secretion of the histidine mutants, forcing tail opening and RDEL accessibility. Client-induced RDEL exposure allows retrieval of proteins from distinct stations along the secretory pathway, as indicated by the changes in O-glycosylation patterns upon over-expression of different partners. The ensuing gradients may help optimising folding and assembly of different cargoes. Endogenous ERp44 is O-glycosylated and secreted by human primary endometrial cells, suggesting possible pathophysiological roles of these processes. PMID:25097228

Self-Referential Information Alleviates Retrieval Inhibition of Directed Forgetting Effects-An ERP Evidence of Source Memory.

PubMed

Mao, Xinrui; Wang, Yujuan; Wu, Yanhong; Guo, Chunyan

2017-01-01

Directed forgetting (DF) assists in preventing outdated information from interfering with cognitive processing. Previous studies pointed that self-referential items alleviated DF effects due to the elaboration of encoding processes. However, the retrieval mechanism of this phenomenon remains unknown. Based on the dual-process framework of recognition, the retrieval of self-referential information was involved in familiarity and recollection. Using source memory tasks combined with event-related potential (ERP) recording, our research investigated the retrieval processes of alleviative DF effects elicited by self-referential information. The FN400 (frontal negativity at 400 ms) is a frontal potential at 300-500 ms related to familiarity and the late positive complex (LPC) is a later parietal potential at 500-800 ms related to recollection. The FN400 effects of source memory suggested that familiarity processes were promoted by self-referential effects without the modulation of to-be-forgotten (TBF) instruction. The ERP results of DF effects were involved with LPCs of source memory, which indexed retrieval processing of recollection. The other-referential source memory of TBF instruction caused the absence of LPC effects, while the self-referential source memory of TBF instruction still elicited the significant LPC effects. Therefore, our neural findings suggested that self-referential processing improved both familiarity and recollection. Furthermore, the self-referential processing advantage which was caused by the autobiographical retrieval alleviated retrieval inhibition of DF, supporting that the self-referential source memory alleviated DF effects.

Self-Referential Information Alleviates Retrieval Inhibition of Directed Forgetting Effects—An ERP Evidence of Source Memory

PubMed Central

Mao, Xinrui; Wang, Yujuan; Wu, Yanhong; Guo, Chunyan

2017-01-01

Directed forgetting (DF) assists in preventing outdated information from interfering with cognitive processing. Previous studies pointed that self-referential items alleviated DF effects due to the elaboration of encoding processes. However, the retrieval mechanism of this phenomenon remains unknown. Based on the dual-process framework of recognition, the retrieval of self-referential information was involved in familiarity and recollection. Using source memory tasks combined with event-related potential (ERP) recording, our research investigated the retrieval processes of alleviative DF effects elicited by self-referential information. The FN400 (frontal negativity at 400 ms) is a frontal potential at 300–500 ms related to familiarity and the late positive complex (LPC) is a later parietal potential at 500–800 ms related to recollection. The FN400 effects of source memory suggested that familiarity processes were promoted by self-referential effects without the modulation of to-be-forgotten (TBF) instruction. The ERP results of DF effects were involved with LPCs of source memory, which indexed retrieval processing of recollection. The other-referential source memory of TBF instruction caused the absence of LPC effects, while the self-referential source memory of TBF instruction still elicited the significant LPC effects. Therefore, our neural findings suggested that self-referential processing improved both familiarity and recollection. Furthermore, the self-referential processing advantage which was caused by the autobiographical retrieval alleviated retrieval inhibition of DF, supporting that the self-referential source memory alleviated DF effects. PMID:29066962

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.

[Q:] When would you prefer a SOSSAGE to a SAUSAGE? [A:] At about 100 msec. ERP correlates of orthographic typicality and lexicality in written word recognition.

PubMed

Hauk, O; Patterson, K; Woollams, A; Watling, L; Pulvermüller, F; Rogers, T T

2006-05-01

Using a speeded lexical decision task, event-related potentials (ERPs), and minimum norm current source estimates, we investigated early spatiotemporal aspects of cortical activation elicited by words and pseudo-words that varied in their orthographic typicality, that is, in the frequency of their component letter pairs (bi-grams) and triplets (tri-grams). At around 100 msec after stimulus onset, the ERP pattern revealed a significant typicality effect, where words and pseudo-words with atypical orthography (e.g., yacht, cacht) elicited stronger brain activation than items characterized by typical spelling patterns (cart, yart). At approximately 200 msec, the ERP pattern revealed a significant lexicality effect, with pseudo-words eliciting stronger brain activity than words. The two main factors interacted significantly at around 160 msec, where words showed a typicality effect but pseudo-words did not. The principal cortical sources of the effects of both typicality and lexicality were localized in the inferior temporal cortex. Around 160 msec, atypical words elicited the stronger source currents in the left anterior inferior temporal cortex, whereas the left perisylvian cortex was the site of greater activation to typical words. Our data support distinct but interactive processing stages in word recognition, with surface features of the stimulus being processed before the word as a meaningful lexical entry. The interaction of typicality and lexicality can be explained by integration of information from the early form-based system and lexicosemantic processes.

Event-related potential variations in the encoding and retrieval of different amounts of contextual information.

PubMed

Estrada-Manilla, Cinthya; Cansino, Selene

2012-06-15

Episodic memory events occur within multidimensional contexts; however, the electrophysiological manifestations associated with processing of more than one context have been rarely investigated. The effect of the amount of context on the ERPs was studied using two single and one double source memory tasks and by comparing full and partial context retrieval within a double source task. The single source tasks elicited waveforms with a larger amplitude during successful encoding and retrieval than the double source task. Compared with the waveforms elicited with a full source response, a partial source response elicited waveforms with a smaller amplitude, probably because the retrieval success for one context was combined with the retrieval attempt processes for the missing source. Comparing the tasks revealed that the larger the amount of contextual information processed, the smaller the amplitude of the ERPs, indicating that greater effort or further control processes were required during double source retrieval. Copyright © 2012 Elsevier B.V. All rights reserved.

Electrophysiological correlates of cocktail-party listening.

PubMed

Lewald, Jörg; Getzmann, Stephan

2015-10-01

Detecting, localizing, and selectively attending to a particular sound source of interest in complex auditory scenes composed of multiple competing sources is a remarkable capacity of the human auditory system. The neural basis of this so-called "cocktail-party effect" has remained largely unknown. Here, we studied the cortical network engaged in solving the "cocktail-party" problem, using event-related potentials (ERPs) in combination with two tasks demanding horizontal localization of a naturalistic target sound presented either in silence or in the presence of multiple competing sound sources. Presentation of multiple sound sources, as compared to single sources, induced an increased P1 amplitude, a reduction in N1, and a strong N2 component, resulting in a pronounced negativity in the ERP difference waveform (N2d) around 260 ms after stimulus onset. About 100 ms later, the anterior contralateral N2 subcomponent (N2ac) occurred in the multiple-sources condition, as computed from the amplitude difference for targets in the left minus right hemispaces. Cortical source analyses of the ERP modulation, resulting from the contrast of multiple vs. single sources, generally revealed an initial enhancement of electrical activity in right temporo-parietal areas, including auditory cortex, by multiple sources (at P1) that is followed by a reduction, with the primary sources shifting from right inferior parietal lobule (at N1) to left dorso-frontal cortex (at N2d). Thus, cocktail-party listening, as compared to single-source localization, appears to be based on a complex chronology of successive electrical activities within a specific cortical network involved in spatial hearing in complex situations. Copyright © 2015 Elsevier B.V. All rights reserved.

The effects of aging on emotion-induced modulations of source retrieval ERPs: evidence for valence biases.

PubMed

Newsome, Rachel N; Dulas, Michael R; Duarte, Audrey

2012-12-01

Many behavioral studies have shown that memory is enhanced for emotionally salient events across the lifespan. It has been suggested that this mnemonic boost may be observed for both age groups, particularly the old, in part because emotional information is retrieved with less effort than neutral information. Neuroimaging evidence suggests that inefficient retrieval processing (temporally delayed and attenuated) may contribute to age-related impairments in episodic memory for neutral events. It is not entirely clear whether emotional salience may reduce these age-related changes in neural activity associated with episodic retrieval for neutral events. Here, we investigated these ideas using event-related potentials (ERPs) to assess the neural correlates of successful source memory retrieval ("old-new effects") for neutral and emotional (negative and positive) images. Behavioral results showed that older adults demonstrated source memory impairments compared to the young but that both groups showed reduced source memory accuracy for negative compared to positive and neutral images; most likely due to an arousal-induced memory tradeoff for the negative images, which were subjectively more arousing than both positive and neutral images. ERP results showed that early onsetting old-new effects, between 100 and 300 ms, were observed for emotional but not neutral images in both age groups. Interestingly, these early effects were observed for negative items in the young and for positive items in the old. These ERP findings offer support for the idea that emotional events may be retrieved more automatically than neutral events across the lifespan. Furthermore, we suggest that very early retrieval mechanisms, possibly perceptual priming or familiarity, may underlie the negativity and positivity effects sometimes observed in the young and old, respectively, for various behavioral measures of attention and memory. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

The ERP signature of the contextual diversity effect in visual word recognition.

PubMed

Vergara-Martínez, Marta; Comesaña, Montserrat; Perea, Manuel

2017-06-01

Behavioral experiments have revealed that words appearing in many different contexts are responded to faster than words that appear in few contexts. Although this contextual diversity (CD) effect has been found to be stronger than the word-frequency (WF) effect, it is a matter of debate whether the facilitative effects of CD and WF reflect the same underlying mechanisms. The analysis of the electrophysiological correlates of CD may shed some light on this issue. This experiment is the first to examine the ERPs to high- and low-CD words when WF is controlled for. Results revealed that while high-CD words produced faster responses than low-CD words, their ERPs showed larger negativities (225-325 ms) than low-CD words. This result goes in the opposite direction of the ERP WF effect (high-frequency words elicit smaller N400 amplitudes than low-frequency words). The direction and scalp distribution of the CD effect resembled the ERP effects associated with "semantic richness." Thus, while apparently related, CD and WF originate from different sources during the access of lexical-semantic representations.

Item and source memory for emotional associates is mediated by different retrieval processes.

PubMed

Ventura-Bort, Carlos; Dolcos, Florin; Wendt, Julia; Wirkner, Janine; Hamm, Alfons O; Weymar, Mathias

2017-12-12

Recent event-related potential (ERP) data showed that neutral objects encoded in emotional background pictures were better remembered than objects encoded in neutral contexts, when recognition memory was tested one week later. In the present study, we investigated whether this long-term memory advantage for items is also associated with correct memory for contextual source details. Furthermore, we were interested in the possibly dissociable contribution of familiarity and recollection processes (using a Remember/Know procedure). The results revealed that item memory performance was mainly driven by the subjective experience of familiarity, irrespective of whether the objects were previously encoded in emotional or neutral contexts. Correct source memory for the associated background picture, however, was driven by recollection and enhanced when the content was emotional. In ERPs, correctly recognized old objects evoked frontal ERP Old/New effects (300-500ms), irrespective of context category. As in our previous study (Ventura-Bort et al., 2016b), retrieval for objects from emotional contexts was associated with larger parietal Old/New differences (600-800ms), indicating stronger involvement of recollection. Thus, the results suggest a stronger contribution of recollection-based retrieval to item and contextual background source memory for neutral information associated with an emotional event. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dipole source localization of event-related brain activity indicative of an early visual selective attention deficit in ADHD children.

PubMed

Jonkman, L M; Kenemans, J L; Kemner, C; Verbaten, M N; van Engeland, H

2004-07-01

This study was aimed at investigating whether attention-deficit hyperactivity disorder (ADHD) children suffer from specific early selective attention deficits in the visual modality with the aid of event-related brain potentials (ERPs). Furthermore, brain source localization was applied to identify brain areas underlying possible deficits in selective visual processing in ADHD children. A two-channel visual color selection task was administered to 18 ADHD and 18 control subjects in the age range of 7-13 years and ERP activity was derived from 30 electrodes. ADHD children exhibited lower perceptual sensitivity scores resulting in poorer target selection. The ERP data suggested an early selective-attention deficit as manifested in smaller frontal positive activity (frontal selection positivity; FSP) in ADHD children around 200 ms whereas later occipital and fronto-central negative activity (OSN and N2b; 200-400 ms latency) appeared to be unaffected. Source localization explained the FSP by posterior-medial equivalent dipoles in control subjects, which may reflect the contribution of numerous surrounding areas. ADHD children have problems with selective visual processing that might be caused by a specific early filtering deficit (absent FSP) occurring around 200 ms. The neural sources underlying these problems have to be further identified. Source localization also suggested abnormalities in the 200-400 ms time range, pertaining to the distribution of attention-modulated activity in lateral frontal areas.

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'.

PSPs and ERPs: applying the dynamics of post-synaptic potentials to individual units in simulation of temporally extended Event-Related Potential reading data.

PubMed

Laszlo, Sarah; Armstrong, Blair C

2014-05-01

The Parallel Distributed Processing (PDP) framework is built on neural-style computation, and is thus well-suited for simulating the neural implementation of cognition. However, relatively little cognitive modeling work has concerned neural measures, instead focusing on behavior. Here, we extend a PDP model of reading-related components in the Event-Related Potential (ERP) to simulation of the N400 repetition effect. We accomplish this by incorporating the dynamics of cortical post-synaptic potentials--the source of the ERP signal--into the model. Simulations demonstrate that application of these dynamics is critical for model elicitation of repetition effects in the time and frequency domains. We conclude that by advancing a neurocomputational understanding of repetition effects, we are able to posit an interpretation of their source that is both explicitly specified and mechanistically different from the well-accepted cognitive one. Copyright © 2014 Elsevier Inc. All rights reserved.

Spatio-temporal dynamics of processing non-symbolic number: An ERP source localization study

PubMed Central

Hyde, Daniel C.; Spelke, Elizabeth S.

2013-01-01

Coordinated studies with adults, infants, and nonhuman animals provide evidence for two distinct systems of non-verbal number representation. The ‘parallel individuation’ system selects and retains information about 1–3 individual entities and the ‘numerical magnitude’ system establishes representations of the approximate cardinal value of a group. Recent ERP work has demonstrated that these systems reliably evoke functionally and temporally distinct patterns of brain response that correspond to established behavioral signatures. However, relatively little is known about the neural generators of these ERP signatures. To address this question, we targeted known ERP signatures of these systems, by contrasting processing of small versus large non-symbolic numbers, and used a source localization algorithm (LORETA) to identify their cortical origins. Early processing of small numbers, showing the signature effects of parallel individuation on the N1 (∼150 ms), was localized primarily to extrastriate visual regions. In contrast, qualitatively and temporally distinct processing of large numbers, showing the signatures of approximate number representation on the mid-latency P2p (∼200–250 ms), was localized primarily to right intraparietal regions. In comparison, mid-latency small number processing was localized to the right temporal-parietal junction and left-lateralized intraparietal regions. These results add spatial information to the emerging ERP literature documenting the process by which we represent number. Furthermore, these results substantiate recent claims that early attentional processes determine whether a collection of objects will be represented through parallel individuation or as an approximate numerical magnitude by providing evidence that downstream processing diverges to distinct cortical regions. PMID:21830257

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.

Progressive quality control of secretory proteins in the early secretory compartment by ERp44.

PubMed

Sannino, Sara; Anelli, Tiziana; Cortini, Margherita; Masui, Shoji; Degano, Massimo; Fagioli, Claudio; Inaba, Kenji; Sitia, Roberto

2014-10-01

ERp44 is a pH-regulated chaperone of the secretory pathway. In the acidic milieu of the Golgi, its C-terminal tail changes conformation, simultaneously exposing the substrate-binding site for cargo capture and the RDEL motif for ER retrieval through interactions with cognate receptors. Protonation of cysteine 29 in the active site allows tail movements in vitro and in vivo. Here, we show that conserved histidine residues in the C-terminal tail also regulate ERp44 in vivo. Mutants lacking these histidine residues retain substrates more efficiently. Surprisingly, they are also O-glycosylated and partially secreted. Co-expression of client proteins prevents secretion of the histidine mutants, forcing tail opening and RDEL accessibility. Client-induced RDEL exposure allows retrieval of proteins from distinct stations along the secretory pathway, as indicated by the changes in O-glycosylation patterns upon overexpression of different partners. The ensuing gradients might help to optimize folding and assembly of different cargoes. Endogenous ERp44 is O-glycosylated and secreted by human primary endometrial cells, suggesting possible pathophysiological roles of these processes. © 2014. Published by The Company of Biologists Ltd.

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.

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.

Electrophysiological Evidence for Domain-General Processes in Task-Switching

PubMed Central

Capizzi, Mariagrazia; Ambrosini, Ettore; Arbula, Sandra; Mazzonetto, Ilaria; Vallesi, Antonino

2016-01-01

The ability to flexibly switch between tasks is a hallmark of cognitive control. Despite previous studies that have investigated whether different task-switching types would be mediated by distinct or overlapping neural mechanisms, no definitive consensus has been reached on this question yet. Here, we aimed at directly addressing this issue by recording the event-related potentials (ERPs) elicited by two types of task-switching occurring in the context of spatial and verbal cognitive domains. Source analysis was also applied to the ERP data in order to track the spatial dynamics of brain activity underlying task-switching abilities. In separate blocks of trials, participants had to perform either spatial or verbal switching tasks both of which employed the same type of stimuli. The ERP analysis, which was carried out through a channel- and time-uninformed mass univariate approach, showed no significant differences between the spatial and verbal domains in the modulation of switch and repeat trials. Specifically, relative to repeat trials, switch trials in both domains were associated with a first larger positivity developing over left parieto-occipital electrodes and with a subsequent larger negativity distributed over mid-left fronto-central sites. The source analysis reconstruction for the two ERP components complemented these findings by highlighting the involvement of left-lateralized prefrontal areas in task-switching. Overall, our results join and extend recent research confirming the existence of left-lateralized domain-general task-switching processes. PMID:27047366

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.

Non-target adjacent stimuli classification improves performance of classical ERP-based brain computer interface

NASA Astrophysics Data System (ADS)

Ceballos, G. A.; Hernández, L. F.

2015-04-01

Objective. The classical ERP-based speller, or P300 Speller, is one of the most commonly used paradigms in the field of Brain Computer Interfaces (BCI). Several alterations to the visual stimuli presentation system have been developed to avoid unfavorable effects elicited by adjacent stimuli. However, there has been little, if any, regard to useful information contained in responses to adjacent stimuli about spatial location of target symbols. This paper aims to demonstrate that combining the classification of non-target adjacent stimuli with standard classification (target versus non-target) significantly improves classical ERP-based speller efficiency. Approach. Four SWLDA classifiers were trained and combined with the standard classifier: the lower row, upper row, right column and left column classifiers. This new feature extraction procedure and the classification method were carried out on three open databases: the UAM P300 database (Universidad Autonoma Metropolitana, Mexico), BCI competition II (dataset IIb) and BCI competition III (dataset II). Main results. The inclusion of the classification of non-target adjacent stimuli improves target classification in the classical row/column paradigm. A gain in mean single trial classification of 9.6% and an overall improvement of 25% in simulated spelling speed was achieved. Significance. We have provided further evidence that the ERPs produced by adjacent stimuli present discriminable features, which could provide additional information about the spatial location of intended symbols. This work promotes the searching of information on the peripheral stimulation responses to improve the performance of emerging visual ERP-based spellers.

Neural activity associated with metaphor comprehension: spatial analysis.

PubMed

Sotillo, María; Carretié, Luis; Hinojosa, José A; Tapia, Manuel; Mercado, Francisco; López-Martín, Sara; Albert, Jacobo

2005-01-03

Though neuropsychological data indicate that the right hemisphere (RH) plays a major role in metaphor processing, other studies suggest that, at least during some phases of this processing, a RH advantage may not exist. The present study explores, through a temporally agile neural signal--the event-related potentials (ERPs)--, and through source-localization algorithms applied to ERP recordings, whether the crucial phase of metaphor comprehension presents or not a RH advantage. Participants (n=24) were submitted to a S1-S2 experimental paradigm. S1 consisted of visually presented metaphoric sentences (e.g., "Green lung of the city"), followed by S2, which consisted of words that could (i.e., "Park") or could not (i.e., "Semaphore") be defined by S1. ERPs elicited by S2 were analyzed using temporal principal component analysis (tPCA) and source-localization algorithms. These analyses revealed that metaphorically related S2 words showed significantly higher N400 amplitudes than non-related S2 words. Source-localization algorithms showed differential activity between the two S2 conditions in the right middle/superior temporal areas. These results support the existence of an important RH contribution to (at least) one phase of metaphor processing and, furthermore, implicate the temporal cortex with respect to that contribution.

Modeling the effects of changes in new source review on national SO2 and NOx emissions from electricity-generating units.

PubMed

Evans, David A; Hobbs, Benjamin F; Oren, Craig; Palmer, Karen L

2008-01-15

The Clean Air Act establishes New Source Review (NSR) programs that apply to construction or modification of major stationary sources. In 2002 and 2003, EPA revised its rules to narrow NSR's coverage of renovations. Congress mandated a National Research Council study of the revisions' impacts. In that study, we used an electricity-sector model to explore possible effects of the equipment replacement provision (ERP), the principal NSR change directed at power plants. We find that, assuming implementation of the Clean Air Interstate Rule (CAIR), tight enforcement of the prerevision NSR rules would likely lead to no or limited decreases in national emissions compared to policies such as ERP. However, emissions might shift forward in time because the previous NSR rules would depress allowance prices, discouraging banking and encouraging allowance use. Only under the most aggressive prerevision NSR enforcement scenario, in which essentially all coal capacity is compelled to retrofit controls by 2020, do NOx emissions fall below ERP levels. Even then, total 2007-2020 SO2 emissions are unaffected. Further decreases in national emissions could be accomplished more cheaply by tighter emissions caps than through NSR because caps provide incentives for efficient operating strategies, such as fuel switching, as well as retrofits.

Cortical substrates and functional correlates of auditory deviance processing deficits in schizophrenia

PubMed Central

Rissling, Anthony J.; Miyakoshi, Makoto; Sugar, Catherine A.; Braff, David L.; Makeig, Scott; Light, Gregory A.

2014-01-01

Although sensory processing abnormalities contribute to widespread cognitive and psychosocial impairments in schizophrenia (SZ) patients, scalp-channel measures of averaged event-related potentials (ERPs) mix contributions from distinct cortical source-area generators, diluting the functional relevance of channel-based ERP measures. SZ patients (n = 42) and non-psychiatric comparison subjects (n = 47) participated in a passive auditory duration oddball paradigm, eliciting a triphasic (Deviant−Standard) tone ERP difference complex, here termed the auditory deviance response (ADR), comprised of a mid-frontal mismatch negativity (MMN), P3a positivity, and re-orienting negativity (RON) peak sequence. To identify its cortical sources and to assess possible relationships between their response contributions and clinical SZ measures, we applied independent component analysis to the continuous 68-channel EEG data and clustered the resulting independent components (ICs) across subjects on spectral, ERP, and topographic similarities. Six IC clusters centered in right superior temporal, right inferior frontal, ventral mid-cingulate, anterior cingulate, medial orbitofrontal, and dorsal mid-cingulate cortex each made triphasic response contributions. Although correlations between measures of SZ clinical, cognitive, and psychosocial functioning and standard (Fz) scalp-channel ADR peak measures were weak or absent, for at least four IC clusters one or more significant correlations emerged. In particular, differences in MMN peak amplitude in the right superior temporal IC cluster accounted for 48% of the variance in SZ-subject performance on tasks necessary for real-world functioning and medial orbitofrontal cluster P3a amplitude accounted for 40%/54% of SZ-subject variance in positive/negative symptoms. Thus, source-resolved auditory deviance response measures including MMN may be highly sensitive to SZ clinical, cognitive, and functional characteristics. PMID:25379456

Event-Related Potential (ERP) Evidence for Varied Recollection during Source Monitoring

ERIC Educational Resources Information Center

Leynes, P. Andrew; Phillips, Michelle C.

2008-01-01

The source monitoring framework (SMF; M. K. Johnson, S. Hashtroudi, & D. S. Lindsay, 1993) posits that source monitoring can be supported by varying degrees of recollection. Source judgments were made for words heard at study (male or female voice) followed by remember/know (RK) judgments in order to assess differences in degrees of recollection…

Combat Veterans with PTSD after Mild TBI Exhibit Greater ERPs from Posterior-medial Cortical Areas While Appraising Facial Features

DTIC Science & Technology

2014-01-01

K.Y., Kim, D.W., Im, C.H., Lee, S.H., 2011. Source imaging of P300 auditory evoked potentials and clinical correlations in patients with posttraumatic...Neural correlates of memories of childhood sexual abuse in womenwith and without posttraumatic stress disorder. Am. J. Psychiatry 156, 1787–1795...S., Zhang, Q., 2011. Neural mechanisms of subliminal priming for traumatic episodic memory: an ERP study. Neurosci. Lett. 498, 10–14. Zhang, K

Synthetic event-related potentials: a computational bridge between neurolinguistic models and experiments.

PubMed

Barrès, Victor; Simons, Arthur; Arbib, Michael

2013-01-01

Our previous work developed Synthetic Brain Imaging to link neural and schema network models of cognition and behavior to PET and fMRI studies of brain function. We here extend this approach to Synthetic Event-Related Potentials (Synthetic ERP). Although the method is of general applicability, we focus on ERP correlates of language processing in the human brain. The method has two components: Phase 1: To generate cortical electro-magnetic source activity from neural or schema network models; and Phase 2: To generate known neurolinguistic ERP data (ERP scalp voltage topographies and waveforms) from putative cortical source distributions and activities within a realistic anatomical model of the human brain and head. To illustrate the challenges of Phase 2 of the methodology, spatiotemporal information from Friederici's 2002 model of auditory language comprehension was used to define cortical regions and time courses of activation for implementation within a forward model of ERP data. The cortical regions from the 2002 model were modeled using atlas-based masks overlaid on the MNI high definition single subject cortical mesh. The electromagnetic contribution of each region was modeled using current dipoles whose position and orientation were constrained by the cortical geometry. In linking neural network computation via EEG forward modeling to empirical results in neurolinguistics, we emphasize the need for neural network models to link their architecture to geometrically sound models of the cortical surface, and the need for conceptual models to refine and adopt brain-atlas based approaches to allow precise brain anchoring of their modules. The detailed analysis of Phase 2 sets the stage for a brief introduction to Phase 1 of the program, including the case for a schema-theoretic approach to language production and perception presented in detail elsewhere. Unlike Dynamic Causal Modeling (DCM) and Bojak's mean field model, Synthetic ERP builds on models of networks that mediate the relation between the brain's inputs, outputs, and internal states in executing a specific task. The neural networks used for Synthetic ERP must include neuroanatomically realistic placement and orientation of the cortical pyramidal neurons. These constraints pose exciting challenges for future work in neural network modeling that is applicable to systems and cognitive neuroscience. Copyright © 2012 Elsevier Ltd. All rights reserved.

EEG signatures of arm isometric exertions in preparation, planning and execution.

PubMed

Nasseroleslami, Bahman; Lakany, Heba; Conway, Bernard A

2014-04-15

The electroencephalographic (EEG) activity patterns in humans during motor behaviour provide insight into normal motor control processes and for diagnostic and rehabilitation applications. While the patterns preceding brisk voluntary movements, and especially movement execution, are well described, there are few EEG studies that address the cortical activation patterns seen in isometric exertions and their planning. In this paper, we report on time and time-frequency EEG signatures in experiments in normal subjects (n=8), using multichannel EEG during motor preparation, planning and execution of directional centre-out arm isometric exertions performed at the wrist in the horizontal plane, in response to instruction-delay visual cues. Our observations suggest that isometric force exertions are accompanied by transient and sustained event-related potentials (ERP) and event-related (de-)synchronisations (ERD/ERS), comparable to those of a movement task. Furthermore, the ERPs and ERD/ERS are also observed during preparation and planning of the isometric task. Comparison of ear-lobe-referenced and surface Laplacian ERPs indicates the contribution of superficial sources in supplementary and pre-motor (FC(z)), parietal (CP(z)) and primary motor cortical areas (C₁ and FC₁) to ERPs (primarily negative peaks in frontal and positive peaks in parietal areas), but contribution of deep sources to sustained time-domain potentials (negativity in planning and positivity in execution). Transient and sustained ERD patterns in μ and β frequency bands of ear-lobe-referenced and surface Laplacian EEG indicate the contribution of both superficial and deep sources to ERD/ERS. As no physical displacement happens during the task, we can infer that the underlying mechanisms of motor-related ERPs and ERD/ERS patterns do not only depend on change in limb coordinate or muscle-length-dependent ascending sensory information and are primary generated by motor preparation, direction-dependent planning and execution of isometric motor tasks. The results contribute to our understanding of the functions of different brain regions during voluntary motor tasks and their activity signatures in EEG can shed light on the relationships between large-scale recordings such as EEG and other recordings such as single unit activity and fMRI in this context. Copyright © 2013 Elsevier Inc. All rights reserved.

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.

Within-subject joint independent component analysis of simultaneous fMRI/ERP in an auditory oddball paradigm

PubMed Central

MANGALATHU-ARUMANA, J.; BEARDSLEY, S. A.; LIEBENTHAL, E.

2012-01-01

The integration of event-related potential (ERP) and functional magnetic resonance imaging (fMRI) can contribute to characterizing neural networks with high temporal and spatial resolution. This research aimed to determine the sensitivity and limitations of applying joint independent component analysis (jICA) within-subjects, for ERP and fMRI data collected simultaneously in a parametric auditory frequency oddball paradigm. In a group of 20 subjects, an increase in ERP peak amplitude ranging 1–8 μV in the time window of the P300 (350–700ms), and a correlated increase in fMRI signal in a network of regions including the right superior temporal and supramarginal gyri, was observed with the increase in deviant frequency difference. JICA of the same ERP and fMRI group data revealed activity in a similar network, albeit with stronger amplitude and larger extent. In addition, activity in the left pre- and post- central gyri, likely associated with right hand somato-motor response, was observed only with the jICA approach. Within-subject, the jICA approach revealed significantly stronger and more extensive activity in the brain regions associated with the auditory P300 than the P300 linear regression analysis. The results suggest that with the incorporation of spatial and temporal information from both imaging modalities, jICA may be a more sensitive method for extracting common sources of activity between ERP and fMRI. PMID:22377443

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

Electrocortical changes associated with minocycline treatment in fragile X syndrome.

PubMed

Schneider, Andrea; Leigh, Mary Jacena; Adams, Patrick; Nanakul, Rawi; Chechi, Tasleem; Olichney, John; Hagerman, Randi; Hessl, David

2013-10-01

Minocycline normalizes synaptic connections and behavior in the knockout mouse model of fragile X syndrome (FXS). Human-targeted treatment trials with minocycline have shown benefits in behavioral measures and parent reports. Event-related potentials (ERPs) may provide a sensitive method of monitoring treatment response and changes in coordinated brain activity. Measurement of electrocortical changes due to minocycline was done in a double-blind, placebo-controlled crossover treatment trial in children with FXS. Children with FXS (Meanage 10.5 years) were randomized to minocycline or placebo treatment for 3 months then changed to the other treatment for 3 months. The minocycline dosage ranged from 25-100 mg daily, based on weight. Twelve individuals with FXS (eight male, four female) completed ERP studies using a passive auditory oddball paradigm. Current source density (CSD) and ERP analysis at baseline showed high-amplitude, long-latency components over temporal regions. After 3 months of treatment with minocycline, the temporal N1 and P2 amplitudes were significantly reduced compared with placebo. There was a significant amplitude increase of the central P2 component on minocycline. Electrocortical habituation to auditory stimuli improved with minocycline treatment. Our study demonstrated improvements of the ERP in children with FXS treated with minocycline, and the potential feasibility and sensitivity of ERPs as a cognitive biomarker in FXS treatment trials.

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.

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.

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

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

Measuring the face-sensitive N170 with a gaming EEG system: A validation study.

PubMed

de Lissa, Peter; Sörensen, Sidsel; Badcock, Nicholas; Thie, Johnson; McArthur, Genevieve

2015-09-30

The N170 is a "face-sensitive" event-related potential (ERP) that occurs at around 170ms over occipito-temporal brain regions. The N170's potential to provide insight into the neural processing of faces in certain populations (e.g., children and adults with cognitive impairments) is limited by its measurement in scientific laboratories that can appear threatening to some people. The advent of cheap, easy-to-use portable gaming EEG systems provides an opportunity to record EEG in new contexts and populations. This study tested the validity of the face-sensitive N170 ERP measured with an adapted commercial EEG system (the Emotiv EPOC) that is used at home by gamers. The N170 recorded through both the gaming EEG system and the research EEG system exhibited face-sensitivity, with larger mean amplitudes in response to the face stimuli than the non-face stimuli, and a delayed N170 peak in response to face inversion. The EPOC system produced very similar N170 ERPs to a research-grade Neuroscan system, and was capable of recording face-sensitivity in the N170, validating its use as research tool in this arena. This opens new possibilities for measuring the face-sensitive N170 ERP in people who cannot travel to a traditional ERP laboratory (e.g., elderly people in care), who cannot tolerate laboratory conditions (e.g., people with autism), or who need to be tested in situ for practical or experimental reasons (e.g., children in schools). Copyright © 2015 Elsevier B.V. All rights reserved.

Modeling the effects of changes in new source review on national SO{sub 2} and NOx emissions from electricity-generating units

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

David A. Evans; Benjamin F. Hobbs; Craig Oren

2008-01-15

The Clean Air Act establishes New Source Review (NSR) programs that apply to construction or modification of major stationary sources. In 2002 and 2003, EPA revised its rules to narrow NSR's coverage of renovations. Congress mandated a National Research Council study of the revisions' impacts. In that study, we used an electricity-sector model to explore possible effects of the equipment replacement provision (ERP), the principal NSR change directed at power plants. We find that, assuming implementation of the Clean Air Interstate Rule (CAIR), tight enforcement of the prerevision NSR rules would likely lead to no or limited decreases in nationalmore » emissions compared to policies such as ERP. However, emissions might shift forward in time because the previous NSR rules would depress allowance prices, discouraging banking and encouraging allowance use. Only under the most aggressive prerevision NSR enforcement scenario, in which essentially all coal capacity is compelled to retrofit controls by 2020, do NOx emissions fall below ERP levels. Even then, total 2007-2020 SO{sub 2} emissions are unaffected. Further decreases in national emissions could be accomplished more cheaply by tighter emissions caps than through NSR because caps provide incentives for efficient operating strategies, such as fuel switching, as well as retrofits. 23 refs., 2 figs., 1 tab.« less

Performance comparison of AV1, HEVC, and JVET video codecs on 360 (spherical) video

NASA Astrophysics Data System (ADS)

Topiwala, Pankaj; Dai, Wei; Krishnan, Madhu; Abbas, Adeel; Doshi, Sandeep; Newman, David

2017-09-01

This paper compares the coding efficiency performance on 360 videos, of three software codecs: (a) AV1 video codec from the Alliance for Open Media (AOM); (b) the HEVC Reference Software HM; and (c) the JVET JEM Reference SW. Note that 360 video is especially challenging content, in that one codes full res globally, but typically looks locally (in a viewport), which magnifies errors. These are tested in two different projection formats ERP and RSP, to check consistency. Performance is tabulated for 1-pass encoding on two fronts: (1) objective performance based on end-to-end (E2E) metrics such as SPSNR-NN, and WS-PSNR, currently developed in the JVET committee; and (2) informal subjective assessment of static viewports. Constant quality encoding is performed with all the three codecs for an unbiased comparison of the core coding tools. Our general conclusion is that under constant quality coding, AV1 underperforms HEVC, which underperforms JVET. We also test with rate control, where AV1 currently underperforms the open source X265 HEVC codec. Objective and visual evidence is provided.

fMRI-constrained source analysis reveals early top-down modulations of interference processing using a flanker task.

PubMed

Siemann, Julia; Herrmann, Manfred; Galashan, Daniela

2016-08-01

Usually, incongruent flanker stimuli provoke conflict processing whereas congruent flankers should facilitate task performance. Various behavioral studies reported improved or even absent conflict processing with correctly oriented selective attention. In the present study we attempted to reinvestigate these behavioral effects and to disentangle neuronal activity patterns underlying the attentional cueing effect taking advantage of a combination of the high temporal resolution of Electroencephalographic (EEG) and the spatial resolution of functional magnetic resonance imaging (fMRI). Data from 20 participants were acquired in different sessions per method. We expected the conflict-related N200 event-related potential (ERP) component and areas associated with flanker processing to show validity-specific modulations. Additionally, the spatio-temporal dynamics during cued flanker processing were examined using an fMRI-constrained source analysis approach. In the ERP data we found early differences in flanker processing between validity levels. An early centro-parietal relative positivity for incongruent stimuli occurred only with valid cueing during the N200 time window, while a subsequent fronto-central negativity was specific to invalidly cued interference processing. The source analysis additionally pointed to separate neural generators of these effects. Regional sources in visual areas were involved in conflict processing with valid cueing, while a regional source in the anterior cingulate cortex (ACC) seemed to contribute to the ERP differences with invalid cueing. Moreover, the ACC and precentral gyrus demonstrated an early and a late phase of congruency-related activity differences with invalid cueing. We discuss the first effect to reflect conflict detection and response activation while the latter more likely originated from conflict monitoring and control processes during response competition. Copyright © 2016 Elsevier Inc. All rights reserved.

Neural Patterns of the Implicit Association Test

PubMed Central

Healy, Graham F.; Boran, Lorraine; Smeaton, Alan F.

2015-01-01

The Implicit Association Test (IAT) is a reaction time based categorization task that measures the differential associative strength between bipolar targets and evaluative attribute concepts as an approach to indexing implicit beliefs or biases. An open question exists as to what exactly the IAT measures, and here EEG (Electroencephalography) has been used to investigate the time course of ERPs (Event-related Potential) indices and implicated brain regions in the IAT. IAT-EEG research identifies a number of early (250–450 ms) negative ERPs indexing early-(pre-response) processing stages of the IAT. ERP activity in this time range is known to index processes related to cognitive control and semantic processing. A central focus of these efforts has been to use IAT-ERPs to delineate the implicit and explicit factors contributing to measured IAT effects. Increasing evidence indicates that cognitive control (and related top-down modulation of attention/perceptual processing) may be components in the effective measurement of IAT effects, as factors such as physical setting or task instruction can change an IAT measurement. In this study we further implicate the role of proactive cognitive control and top-down modulation of attention/perceptual processing in the IAT-EEG. We find statistically significant relationships between D-score (a reaction-time based measure of the IAT-effect) and early ERP-time windows, indicating where more rapid word categorizations driving the IAT effect are present, they are at least partly explainable by neural activity not significantly correlated with the IAT measurement itself. Using LORETA, we identify a number of brain regions driving these ERP-IAT relationships notably involving left-temporal, insular, cingulate, medial frontal and parietal cortex in time regions corresponding to the N2- and P3-related activity. The identified brain regions involved with reduced reaction times on congruent blocks coincide with those of previous studies. PMID:26635570

Single-trial event-related potentials to significant stimuli.

PubMed

Rushby, Jacqueline A; Barry, Robert J

2009-11-01

The stimulus-response pattern of the skin conductance response (SCR) was used as a model of the Orienting Reflex (OR) to assess the P1, N1, P2, N2 and late positive complex (LPC/P300) components of the ERP in a simple habituation paradigm, in which a single series of 12 innocuous tones were presented at a very long interstimulus interval (2 min). To maintain their waking state during this boring task, participants were instructed to alternately close or open their eyes to each stimulus. None of the baseline-to-peak ERP measures showed trials effects comparable with the marked habituation over trials shown by the SCRs. Principal Components Analysis was used to decompose the ERP, yielding factors identified as the N1, N2, P3a, P3b and Novelty P3 components. An additional factor represented later eye-movement activity. No trial effects were apparent for the N1, N2, P3a or P3b components. The Novelty P3 showed marked response decrement over trials. These results are discussed in relation to current conceptualisations of the OR.

Spatiotemporal dynamics of processing nonsymbolic number: an event-related potential source localization study.

PubMed

Hyde, Daniel C; Spelke, Elizabeth S

2012-09-01

Coordinated studies with adults, infants, and nonhuman animals provide evidence for two distinct systems of nonverbal number representation. The "parallel individuation" (PI) system selects and retains information about one to three individual entities and the "numerical magnitude" system establishes representations of the approximate cardinal value of a group. Recent event-related potential (ERP) work has demonstrated that these systems reliably evoke functionally and temporally distinct patterns of brain response that correspond to established behavioral signatures. However, relatively little is known about the neural generators of these ERP signatures. To address this question, we targeted known ERP signatures of these systems, by contrasting processing of small versus large nonsymbolic numbers, and used a source localization algorithm (LORETA) to identify their cortical origins. Early processing of small numbers, showing the signature effects of PI on the N1 (∼150 ms), was localized primarily to extrastriate visual regions. In contrast, qualitatively and temporally distinct processing of large numbers, showing the signatures of approximate number representation on the mid-latency P2p (∼200-250 ms), was localized primarily to right intraparietal regions. In comparison, mid-latency small number processing was localized to the right temporal-parietal junction and left-lateralized intraparietal regions. These results add spatial information to the emerging ERP literature documenting the process by which we represent number. Furthermore, these results substantiate recent claims that early attentional processes determine whether a collection of objects will be represented through PI or as an approximate numerical magnitude by providing evidence that downstream processing diverges to distinct cortical regions. Copyright © 2011 Wiley Periodicals, Inc.

Ecological Restoration Programs Induced Amelioration of the Dust Pollution in North China Plain

NASA Astrophysics Data System (ADS)

Long, X.; Tie, X.; Li, G.; Junji, C.

2017-12-01

With Moderate Resolution Imaging Spectroradiometer (MODIS) land cover product (MCD12Q1), we quantitatively evaluate the ecological restoration programs (ERP) induced land cover change in China by calculating gridded the land use fraction (LUF). We clearly capture two obvious vegetation (grass and forest) protective barriers arise between the dust source region DSR and North China Plain NCP from 2011 to 2013. The WRF-DUST model is applied to investigate the impact of ERPs on dust pollution from 2 to 8 March 2016, corresponding to a national dust storm event over China. Despite some model biases, the WRF-DUST model reasonably reproduced the temporal variations of dust storm event, involving IOA of 0.96 and NMB of 2% for DSR, with IOA of 0.83 and NMB of -15% for downwind area of NCP. Generally, the WRF-DUST model well capture the spatial variations and evolutions of dust storm events with episode-average [PMC] correlation coefficient (R) of 0.77, especially the dust storm outbreak and transport evolution, involving daily average [PMC] R of 0.9 and 0.73 on 4-5 March, respectively. It is found that the ERPs generally reduce the dust pollution in NCP, especially for BTH, involving upper dust pollution control benefits of -15.3% (-21.0 μg m-3) for BTH, and -6.2% (-9.3 μg m-3) for NCP. We are the first to conduct model sensitivity studies to quantitatively evaluate the impacts of the ERPs on the dust pollution in NCP. And our narrative is independently based on first-hand sources, whereas government statistics.

Aberrant Processing of Deviant Stimuli in Schizophrenia Revealed by Fusion of FMRI and EEG Data

PubMed Central

Calhoun, VD; Wu, L; Kiehl, KA; Eichele, T; Pearlson, GD

2010-01-01

Background Aberrant electrophysiological and hemodynamic processing of auditory oddball stimuli is among the most robustly documented findings in patients with schizophrenia. However, no study to date has directly examined linked patterns of electrical and hemodynamic differences in patients and controls. Methods In a recent paper we demonstrated a data-driven approach, joint independent component analysis (jICA) to fuse together functional magnetic resonance imaging (fMRI) and event-related potential (ERP) data and elucidated the chronometry of auditory oddball target detection in healthy control subjects. In this paper we extend our fusion method to identify specific differences in the neuronal chronometry of target detection for chronic schizophrenia patients compared to healthy controls. Results We found one linked source, consistent with the N2 response, known to be related to cognitive processing of deviant stimuli, spatially localized to bilateral fronto-temporal regions. This source showed significant between-group differences both in amplitude response and in the fMRI/ERP distribution pattern. These findings are consistent with previous work showing N2 amplitude and latency abnormalities in schizophrenia, and provide new information about the linkage between the two. Conclusions In summary, we use a novel approach to isolate and identify a linked fMRI/ERP component which shows marked differences in chronic schizophrenia patients. We also demonstrate that jointly using both fMRI and ERP measures provides a fully picture of the underlying hemodynamic and electrical changes which are present in patients. Our approach also has broad applicability to other diseases such as autism, Alzheimer’s disease, or bipolar disorder. PMID:21331320

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.

Mechanisms mediating parallel action monitoring in fronto-striatal circuits.

PubMed

Beste, Christian; Ness, Vanessa; Lukas, Carsten; Hoffmann, Rainer; Stüwe, Sven; Falkenstein, Michael; Saft, Carsten

2012-08-01

Flexible response adaptation and the control of conflicting information play a pivotal role in daily life. Yet, little is known about the neuronal mechanisms mediating parallel control of these processes. We examined these mechanisms using a multi-methodological approach that integrated data from event-related potentials (ERPs) with structural MRI data and source localisation using sLORETA. Moreover, we calculated evoked wavelet oscillations. We applied this multi-methodological approach in healthy subjects and patients in a prodromal phase of a major basal ganglia disorder (i.e., Huntington's disease), to directly focus on fronto-striatal networks. Behavioural data indicated, especially the parallel execution of conflict monitoring and flexible response adaptation was modulated across the examined cohorts. When both processes do not co-incide a high integrity of fronto-striatal loops seems to be dispensable. The neurophysiological data suggests that conflict monitoring (reflected by the N2 ERP) and working memory processes (reflected by the P3 ERP) differentially contribute to this pattern of results. Flexible response adaptation under the constraint of high conflict processing affected the N2 and P3 ERP, as well as their delta frequency band oscillations. Yet, modulatory effects were strongest for the N2 ERP and evoked wavelet oscillations in this time range. The N2 ERPs were localized in the anterior cingulate cortex (BA32, BA24). Modulations of the P3 ERP were localized in parietal areas (BA7). In addition, MRI-determined caudate head volume predicted modulations in conflict monitoring, but not working memory processes. The results show how parallel conflict monitoring and flexible adaptation of action is mediated via fronto-striatal networks. While both, response monitoring and working memory processes seem to play a role, especially response selection processes and ACC-basal ganglia networks seem to be the driving force in mediating parallel conflict monitoring and flexible adaptation of actions. Copyright © 2012 Elsevier Inc. All rights reserved.

Familiarity in source memory.

PubMed

Mollison, Matthew V; Curran, Tim

2012-09-01

Familiarity and recollection are thought to be separate processes underlying recognition memory. Event-related potentials (ERPs) dissociate these processes, with an early (approximately 300-500ms) frontal effect relating to familiarity (the FN400) and a later (500-800ms) parietal old/new effect relating to recollection. It has been debated whether source information for a studied item (i.e., contextual associations from when the item was previously encountered) is only accessible through recollection, or whether familiarity can contribute to successful source recognition. It has been shown that familiarity can assist in perceptual source monitoring when the source attribute is an intrinsic property of the item (e.g., an object's surface color), but few studies have examined its contribution to recognizing extrinsic source associations. Extrinsic source associations were examined in three experiments involving memory judgments for pictures of common objects. In Experiment 1, source information was spatial and results suggested that familiarity contributed to accurate source recognition: the FN400 ERP component showed a source accuracy effect, and source accuracy was above chance for items judged to only feel familiar. Source information in Experiment 2 was an extrinsic color association; source accuracy was at chance for familiar items and the FN400 did not differ between correct and incorrect source judgments. Experiment 3 replicated the results using a within-subjects manipulation of spatial vs. color source. Overall, the results suggest that familiarity's contribution to extrinsic source monitoring depends on the type of source information being remembered. Copyright © 2012 Elsevier Ltd. All rights reserved.

EEGLAB: an open source toolbox for analysis of single-trial EEG dynamics including independent component analysis.

PubMed

Delorme, Arnaud; Makeig, Scott

2004-03-15

We have developed a toolbox and graphic user interface, EEGLAB, running under the crossplatform MATLAB environment (The Mathworks, Inc.) for processing collections of single-trial and/or averaged EEG data of any number of channels. Available functions include EEG data, channel and event information importing, data visualization (scrolling, scalp map and dipole model plotting, plus multi-trial ERP-image plots), preprocessing (including artifact rejection, filtering, epoch selection, and averaging), independent component analysis (ICA) and time/frequency decompositions including channel and component cross-coherence supported by bootstrap statistical methods based on data resampling. EEGLAB functions are organized into three layers. Top-layer functions allow users to interact with the data through the graphic interface without needing to use MATLAB syntax. Menu options allow users to tune the behavior of EEGLAB to available memory. Middle-layer functions allow users to customize data processing using command history and interactive 'pop' functions. Experienced MATLAB users can use EEGLAB data structures and stand-alone signal processing functions to write custom and/or batch analysis scripts. Extensive function help and tutorial information are included. A 'plug-in' facility allows easy incorporation of new EEG modules into the main menu. EEGLAB is freely available (http://www.sccn.ucsd.edu/eeglab/) under the GNU public license for noncommercial use and open source development, together with sample data, user tutorial and extensive documentation.

The Neural Basis of Decision-Making and Reward Processing in Adults with Euthymic Bipolar Disorder or Attention-Deficit/Hyperactivity Disorder (ADHD)

PubMed Central

Ibanez, Agustin; Cetkovich, Marcelo; Petroni, Agustin; Urquina, Hugo; Baez, Sandra; Gonzalez-Gadea, Maria Luz; Kamienkowski, Juan Esteban; Torralva, Teresa; Torrente, Fernando; Strejilevich, Sergio; Teitelbaum, Julia; Hurtado, Esteban; Guex, Raphael; Melloni, Margherita; Lischinsky, Alicia; Sigman, Mariano; Manes, Facundo

2012-01-01

Background Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) share DSM-IV criteria in adults and cause problems in decision-making. Nevertheless, no previous report has assessed a decision-making task that includes the examination of the neural correlates of reward and gambling in adults with ADHD and those with BD. Methodology/Principal Findings We used the Iowa gambling task (IGT), a task of rational decision-making under risk (RDMUR) and a rapid-decision gambling task (RDGT) which elicits behavioral measures as well as event-related potentials (ERPs: fERN and P3) in connection to the motivational impact of events. We did not observe between-group differences for decision-making under risk or ambiguity (RDMUR and IGT); however, there were significant differences for the ERP-assessed RDGT. Compared to controls, the ADHD group showed a pattern of impaired learning by feedback (fERN) and insensitivity to reward magnitude (P3). This ERP pattern (fERN and P3) was associated with impulsivity, hyperactivity, executive function and working memory. Compared to controls, the BD group showed fERN- and P3-enhanced responses to reward magnitude regardless of valence. This ERP pattern (fERN and P3) was associated with mood and inhibitory control. Consistent with the ERP findings, an analysis of source location revealed reduced responses of the cingulate cortex to the valence and magnitude of rewards in patients with ADHD and BD. Conclusions/Significance Our data suggest that neurophysiological (ERPs) paradigms such as the RDGT are well suited to assess subclinical decision-making processes in patients with ADHD and BD as well as for linking the cingulate cortex with action monitoring systems. PMID:22624011

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

The neural basis of decision-making and reward processing in adults with euthymic bipolar disorder or attention-deficit/hyperactivity disorder (ADHD).

PubMed

Ibanez, Agustin; Cetkovich, Marcelo; Petroni, Agustin; Urquina, Hugo; Baez, Sandra; Gonzalez-Gadea, Maria Luz; Kamienkowski, Juan Esteban; Torralva, Teresa; Torrente, Fernando; Strejilevich, Sergio; Teitelbaum, Julia; Hurtado, Esteban; Guex, Raphael; Melloni, Margherita; Lischinsky, Alicia; Sigman, Mariano; Manes, Facundo

2012-01-01

Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) share DSM-IV criteria in adults and cause problems in decision-making. Nevertheless, no previous report has assessed a decision-making task that includes the examination of the neural correlates of reward and gambling in adults with ADHD and those with BD. We used the Iowa gambling task (IGT), a task of rational decision-making under risk (RDMUR) and a rapid-decision gambling task (RDGT) which elicits behavioral measures as well as event-related potentials (ERPs: fERN and P3) in connection to the motivational impact of events. We did not observe between-group differences for decision-making under risk or ambiguity (RDMUR and IGT); however, there were significant differences for the ERP-assessed RDGT. Compared to controls, the ADHD group showed a pattern of impaired learning by feedback (fERN) and insensitivity to reward magnitude (P3). This ERP pattern (fERN and P3) was associated with impulsivity, hyperactivity, executive function and working memory. Compared to controls, the BD group showed fERN- and P3-enhanced responses to reward magnitude regardless of valence. This ERP pattern (fERN and P3) was associated with mood and inhibitory control. Consistent with the ERP findings, an analysis of source location revealed reduced responses of the cingulate cortex to the valence and magnitude of rewards in patients with ADHD and BD. Our data suggest that neurophysiological (ERPs) paradigms such as the RDGT are well suited to assess subclinical decision-making processes in patients with ADHD and BD as well as for linking the cingulate cortex with action monitoring systems.

A perspective on the use of an enhanced recovery program in open, non-instrumented day surgery for degenerative lumbar and cervical spinal conditions.

PubMed

Venkata, Hari K; van Dellen, James R

2018-06-01

A means of significantly shortening patients' length of hospital stay, improving their outcome and thereby also reducing costs is to use an enhanced recovery program (ERP) which is increasingly being used in a number of surgical sub-specialties. This paper provides a perspective on its prospective use in a wide-ranging, unselected cohort of patients undergoing open spinal surgery for degenerative lumbar and cervical spinal conditions. Selected spinal cases undergoing day surgery have been increasingly reported. A prospective, unselected, consecutive cohort of 246 cases, over an 18-month period, undergoing open, non-instrumented decompression spinal surgery and using ERP (and the concept of "bundles of care") was analyzed. Nine cases could not be included as they did not fully meet the entry criteria. No routine follow-up was arranged for the study group. The ages ranged widely, from 23-90 years (mean 57). In 187 the surgery for degenerative conditions was lumbar and in 50 cervical. The ASA (American Association of Anesthesiologists) ratings were 108=1; 107=2 and 22=3. Using the United Kingdom (UK) National Health Service (NHS) definitions of length of stay 225 (95%) could be finally classified as "ambulatory" and 12 (5%) were "short stay". A sub-cohort of 126 (53.2%) were "day cases". The follow-up was >1 year for all. There were no wound infections reported; 5 postdischarge cases (2.1%) needed to be seen in the Accident and Emergency (A&E) Department (less than 4 days postsurgery), but none needed re-admission; and there were 7 re-admissions (2.5%), between 4 and 30 days, and of these 6 required a further surgical procedure. There were no long-term instability complications reported in this cohort. ERP can be used for spinal surgery. There were identifiable and correctable medical and social factors found on analysis which could significantly increase the "day cases" number to over 90%.

Revisiting the Incremental Effects of Context on Word Processing: Evidence from Single-Word Event-Related Brain Potentials

PubMed Central

Payne, Brennan R.; Lee, Chia-Lin; Federmeier, Kara D.

2015-01-01

The amplitude of the N400— an event-related potential (ERP) component linked to meaning processing and initial access to semantic memory— is inversely related to the incremental build-up of semantic context over the course of a sentence. We revisited the nature and scope of this incremental context effect, adopting a word-level linear mixed-effects modeling approach, with the goal of probing the continuous and incremental effects of semantic and syntactic context on multiple aspects of lexical processing during sentence comprehension (i.e., effects of word frequency and orthographic neighborhood). First, we replicated the classic word position effect at the single-word level: open-class words showed reductions in N400 amplitude with increasing word position in semantically congruent sentences only. Importantly, we found that accruing sentence context had separable influences on the effects of frequency and neighborhood on the N400. Word frequency effects were reduced with accumulating semantic context. However, orthographic neighborhood was unaffected by accumulating context, showing robust effects on the N400 across all words, even within congruent sentences. Additionally, we found that N400 amplitudes to closed-class words were reduced with incrementally constraining syntactic context in sentences that provided only syntactic constraints. Taken together, our findings indicate that modeling word-level variability in ERPs reveals mechanisms by which different sources of information simultaneously contribute to the unfolding neural dynamics of comprehension. PMID:26311477

Revisiting the incremental effects of context on word processing: Evidence from single-word event-related brain potentials.

PubMed

Payne, Brennan R; Lee, Chia-Lin; Federmeier, Kara D

2015-11-01

The amplitude of the N400-an event-related potential (ERP) component linked to meaning processing and initial access to semantic memory-is inversely related to the incremental buildup of semantic context over the course of a sentence. We revisited the nature and scope of this incremental context effect, adopting a word-level linear mixed-effects modeling approach, with the goal of probing the continuous and incremental effects of semantic and syntactic context on multiple aspects of lexical processing during sentence comprehension (i.e., effects of word frequency and orthographic neighborhood). First, we replicated the classic word-position effect at the single-word level: Open-class words showed reductions in N400 amplitude with increasing word position in semantically congruent sentences only. Importantly, we found that accruing sentence context had separable influences on the effects of frequency and neighborhood on the N400. Word frequency effects were reduced with accumulating semantic context. However, orthographic neighborhood was unaffected by accumulating context, showing robust effects on the N400 across all words, even within congruent sentences. Additionally, we found that N400 amplitudes to closed-class words were reduced with incrementally constraining syntactic context in sentences that provided only syntactic constraints. Taken together, our findings indicate that modeling word-level variability in ERPs reveals mechanisms by which different sources of information simultaneously contribute to the unfolding neural dynamics of comprehension. © 2015 Society for Psychophysiological Research.

Variability of ICA decomposition may impact EEG signals when used to remove eyeblink artifacts

PubMed Central

PONTIFEX, MATTHEW B.; GWIZDALA, KATHRYN L.; PARKS, ANDREW C.; BILLINGER, MARTIN; BRUNNER, CLEMENS

2017-01-01

Despite the growing use of independent component analysis (ICA) algorithms for isolating and removing eyeblink-related activity from EEG data, we have limited understanding of how variability associated with ICA uncertainty may be influencing the reconstructed EEG signal after removing the eyeblink artifact components. To characterize the magnitude of this ICA uncertainty and to understand the extent to which it may influence findings within ERP and EEG investigations, ICA decompositions of EEG data from 32 college-aged young adults were repeated 30 times for three popular ICA algorithms. Following each decomposition, eyeblink components were identified and removed. The remaining components were back-projected, and the resulting clean EEG data were further used to analyze ERPs. Findings revealed that ICA uncertainty results in variation in P3 amplitude as well as variation across all EEG sampling points, but differs across ICA algorithms as a function of the spatial location of the EEG channel. This investigation highlights the potential of ICA uncertainty to introduce additional sources of variance when the data are back-projected without artifact components. Careful selection of ICA algorithms and parameters can reduce the extent to which ICA uncertainty may introduce an additional source of variance within ERP/EEG studies. PMID:28026876

Individual differences in verbal working memory underlie a tradeoff between semantic and structural processing difficulty during language comprehension: An ERP investigation.

PubMed

Kim, Albert E; Oines, Leif; Miyake, Akira

2018-03-01

This study investigated the processes reflected in the widely observed N400 and P600 event-related potential (ERP) effects and tested the hypothesis that the N400 and P600 effects are functionally linked in a tradeoff relationship, constrained in part by individual differences in cognitive ability. Sixty participants read sentences, and ERP effects of semantic anomaly, relative to plausible words, were calculated for each participant. Results suggested qualitatively different ERP patterns across participants: Some individuals generated N400-dominated effects, whereas others generated P600-dominated effects, for the same stimuli. To specify the sources of individual differences in brain responses, we also derived aggregate scores for verbal working memory (WM), nonverbal WM, and language experience/knowledge, based on 6 behavioral measures administered to each participant. Multiple regression analysis pitting these 3 constructs against each other showed that a larger verbal WM capacity was significantly associated with larger P600 and smaller N400 effect amplitudes across individuals, whereas the other constructs did not predict the ERP effects. The results suggest that N400 and P600 brain responses, which may be attributable to semantic integration difficulty and structural processing, respectively, vie for expression when comprehenders encounter semantically unexpected words and that which option wins out is constrained in part by each comprehender's verbal WM capacity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Perception of Dynamic and Static Facial Expressions of Happiness and Disgust Investigated by ERPs and fMRI Constrained Source Analysis

PubMed Central

Trautmann-Lengsfeld, Sina Alexa; Domínguez-Borràs, Judith; Escera, Carles; Herrmann, Manfred; Fehr, Thorsten

2013-01-01

A recent functional magnetic resonance imaging (fMRI) study by our group demonstrated that dynamic emotional faces are more accurately recognized and evoked more widespread patterns of hemodynamic brain responses than static emotional faces. Based on this experimental design, the present study aimed at investigating the spatio-temporal processing of static and dynamic emotional facial expressions in 19 healthy women by means of multi-channel electroencephalography (EEG), event-related potentials (ERP) and fMRI-constrained regional source analyses. ERP analysis showed an increased amplitude of the LPP (late posterior positivity) over centro-parietal regions for static facial expressions of disgust compared to neutral faces. In addition, the LPP was more widespread and temporally prolonged for dynamic compared to static faces of disgust and happiness. fMRI constrained source analysis on static emotional face stimuli indicated the spatio-temporal modulation of predominantly posterior regional brain activation related to the visual processing stream for both emotional valences when compared to the neutral condition in the fusiform gyrus. The spatio-temporal processing of dynamic stimuli yielded enhanced source activity for emotional compared to neutral conditions in temporal (e.g., fusiform gyrus), and frontal regions (e.g., ventromedial prefrontal cortex, medial and inferior frontal cortex) in early and again in later time windows. The present data support the view that dynamic facial displays trigger more information reflected in complex neural networks, in particular because of their changing features potentially triggering sustained activation related to a continuing evaluation of those faces. A combined fMRI and EEG approach thus provides an advanced insight to the spatio-temporal characteristics of emotional face processing, by also revealing additional neural generators, not identifiable by the only use of an fMRI approach. PMID:23818974

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

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.

The relationship between somatic and cognitive-affective depression symptoms and error-related ERP’s

PubMed Central

Bridwell, David A.; Steele, Vaughn R.; Maurer, J. Michael; Kiehl, Kent A.; Calhoun, Vince D.

2014-01-01

Background The symptoms that contribute to the clinical diagnosis of depression likely emerge from, or are related to, underlying cognitive deficits. To understand this relationship further, we examined the relationship between self-reported somatic and cognitive-affective Beck’s Depression Inventory-II (BDI-II) symptoms and aspects of cognitive control reflected in error event-related potential (ERP) responses. Methods Task and assessment data were analyzed within 51 individuals. The group contained a broad distribution of depressive symptoms, as assessed by BDI-II scores. ERP’s were collected following error responses within a go/no-go task. Individual error ERP amplitudes were estimated by conducting group independent component analysis (ICA) on the electroencephalographic (EEG) time series and analyzing the individual reconstructed source epochs. Source error amplitudes were correlated with the subset of BDI-II scores representing somatic and cognitive-affective symptoms. Results We demonstrate a negative relationship between somatic depression symptoms (i.e. fatigue or loss of energy) (after regressing out cognitive-affective scores, age and IQ) and the central-parietal ERP response that peaks at 359 ms. The peak amplitudes within this ERP response were not significantly related to cognitive-affective symptom severity (after regressing out the somatic symptom scores, age, and IQ). Limitations These findings were obtained within a population of female adults from a maximum-security correctional facility. Thus, additional research is required to verify that they generalize to the broad population. Conclusions These results suggest that individuals with greater somatic depression symptoms demonstrate a reduced awareness of behavioral errors, and help clarify the relationship between clinical measures of self-reported depression symptoms and cognitive control. PMID:25451400

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

Neurophysiologic Evaluation of Early Cognitive Development in High-Risk Infants and Toddlers

ERIC Educational Resources Information Center

deRegnier, Raye-Ann

2005-01-01

New knowledge of the perceptual, discriminative, and memory capabilities of very young infants has opened the door to further evaluation of these abilities in infants who have risk factors for cognitive impairments. A neurophysiologic technique that has been very useful in this regard is the recording of event-related potentials (ERPs). The…

Something to sink your teeth into: The presence of teeth augments ERPs to mouth expressions.

PubMed

daSilva, Elizabeth B; Crager, Kirsten; Geisler, Danika; Newbern, Powell; Orem, Benjamin; Puce, Aina

2016-02-15

If the whites of the sclera can impact neural processing of eye expressions (Hardee, Thompson, & Puce, 2008; Whalen et al., 1998), do seen teeth affect neural responses to mouth expressions? Twenty participants (10 females; ages 22-31) viewed avatar mouth images depicting grimaces, smiles and open mouth expressions that were presented with and without teeth. A continuous 256 channel electroencephalogram (EEG) was recorded while subjects completed two tasks: an implicit task evaluating stimulus color and an explicit task evaluating mouth expression valence. Event related potential (ERP) peak amplitudes and latencies and area under the curve (AUC) were measured in individual subject averaged ERPs. Statistical testing revealed a main effect of the presence of Teeth for P100, N170, and vertex positive potential (VPP) amplitudes and for slow positive wave (SPW) AUC. Task by teeth interactions occurred for P250 amplitude, underscoring how explicit task demands can influence neural processing. Arousal ratings co-varied with teeth presence, suggesting that low-level visual features such as teeth may drive the saliency of emotional expressions, and lie at the core of differences in neural processing to different emotional expressions. Copyright © 2015 Elsevier Inc. All rights reserved.

Pharmacogenetics-guided analgesics in major abdominal surgery: Further benefits within an enhanced recovery protocol.

PubMed

Senagore, Anthony J; Champagne, Bradley J; Dosokey, Eslam; Brady, Justin; Steele, Scott R; Reynolds, Harry L; Stein, Sharon L; Delaney, Conor P

2017-03-01

Effective, narcotic sparing analgesia is a major component of Enhanced Recovery Protocols (ERP), however the risk of poor analgesia and opioid related side effects (ORADE) remains an issue related to poor outcomes and satisfaction, and is strongly related to the risk of narcotic dependence after surgery. A variety of genes can impact narcotic and non-steroidal (NSAID) drug efficacy including: the CYP family (drug metabolism-narcotics and NSAID), or COMT/ABCB1/OPRM1 (functional receptor and transport activity for analgesia vs side effects). The purpose of this study was to perform the first assessment of the impact of a pharmacogenetics (PGx) guided selection of analgesics following major abdominal surgery within an ERP. A consecutive series of open and laparoscopic colorectal resections or major ventral hernia repair (PGx group) had a guided analgesic protocol based upon assessment of CYP1A2, CYP2C19, CYP2C9, CYP2D6, CYP3A4, CYP3A5, COMT, OPRM1, and ABCB1 genes. Study patients were compared to a recent historical series of patients (H group) managed using our well validated ERP. The primary outcome measure was the Overall Benefit of Analgesia Score (OBAS). Pain scores were also assessed. The data demonstrated a similar mix of procedures and gender between groups and more than half of the PGx group had revised analgesia from the standard ERP. The PGx group demonstrated significantly lower OBAS scores (p = 0.0.1) from POD1 (3.8 vs 5.4) through POD 5 (3.0 vs 4.5) Analgesia was also superior for the PGx group from POD1 through POD 5 (p = 0.04). Pharmacogenetics guidance resulted in frequent modifications of the analgesic program, resulting in excellent analgesia with a 50% reduction in narcotic consumption, and a reduced incidence of analgesic related side effects compared to our standard ERP. These data suggest further improvement in ERP resulting from a patient centric analgesic, reduced narcotic regimen which provides early and durable pain control with fewer narcotic related side effects. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

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.

Conflict-Specific Aging Effects Mainly Manifest in Early Information Processing Stages-An ERP Study with Different Conflict Types.

PubMed

Korsch, Margarethe; Frühholz, Sascha; Herrmann, Manfred

2016-01-01

Aging is usually accompanied by alterations of cognitive control functions such as conflict processing. Recent research suggests that aging effects on cognitive control seem to vary with degree and source of conflict, and conflict specific aging effects on performance measures as well as neural activation patterns have been shown. However, there is sparse information whether and how aging affects different stages of conflict processing as indicated by event related potentials (ERPs) such as the P2, N2 and P3 components. In the present study, 19 young and 23 elderly adults performed a combined Flanker conflict and stimulus-response-conflict (SRC) task. Analysis of the reaction times (RTs) revealed an increased SRC related conflict effect in elderly. ERP analysis furthermore demonstrated an age-related increase of the P2 amplitude in response to the SRC task. In addition, elderly adults exhibited an increased P3 amplitude modulation induced by incongruent SRC and Flanker conflict trials.

Event-related brain potentials and cognitive processes related to perceptual-motor information transmission.

PubMed

Kopp, Bruno; Wessel, Karl

2010-05-01

In the present study, event-related potentials (ERPs) were recorded to investigate cognitive processes related to the partial transmission of information from stimulus recognition to response preparation. Participants classified two-dimensional visual stimuli with dimensions size and form. One feature combination was designated as the go-target, whereas the other three feature combinations served as no-go distractors. Size discriminability was manipulated across three experimental conditions. N2c and P3a amplitudes were enhanced in response to those distractors that shared the feature from the faster dimension with the target. Moreover, N2c and P3a amplitudes showed a crossover effect: Size distractors evoked more pronounced ERPs under high size discriminability, but form distractors elicited enhanced ERPs under low size discriminability. These results suggest that partial perceptual-motor transmission of information is accompanied by acts of cognitive control and by shifts of attention between the sources of conflicting information. Selection negativity findings imply adaptive allocation of visual feature-based attention across the two stimulus dimensions.

Emotion impairs extrinsic source memory--An ERP study.

PubMed

Mao, Xinrui; You, Yuqi; Li, Wen; Guo, Chunyan

2015-09-01

Substantial advancements in understanding emotional modulation of item memory notwithstanding, controversies remain as to how emotion influences source memory. Using an emotional extrinsic source memory paradigm combined with remember/know judgments and two key event-related potentials (ERPs)-the FN400 (a frontal potential at 300-500 ms related to familiarity) and the LPC (a later parietal potential at 500-700 ms related to recollection), our research investigated the impact of emotion on extrinsic source memory and the underlying processes. We varied a semantic prompt (either "people" or "scene") preceding a study item to manipulate the extrinsic source. Behavioral data indicated a significant effect of emotion on "remember" responses to extrinsic source details, suggesting impaired recollection-based source memory in emotional (both positive and negative) relative to neutral conditions. In parallel, differential FN400 and LPC amplitudes (correctly remembered - incorrectly remembered sources) revealed emotion-related interference, suggesting impaired familiarity and recollection memory of extrinsic sources associated with positive or negative items. These findings thus lend support to the notion of emotion-induced memory trade off: while enhancing memory of central items and intrinsic/integral source details, emotion nevertheless disrupts memory of peripheral contextual details, potentially impairing both familiarity and recollection. Importantly, that positive and negative items result in comparable memory impairment suggests that arousal (vs. affective valence) plays a critical role in modulating dynamic interactions among automatic and elaborate processes involved in memory. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

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.

An electrophysiological index of changes in risk decision-making strategies.

PubMed

Zhang, Dandan; Gu, Ruolei; Wu, Tingting; Broster, Lucas S; Luo, Yi; Jiang, Yang; Luo, Yue-jia

2013-07-01

Human decision-making is significantly modulated by previously experienced outcomes. Using event-related potentials (ERPs), we examined whether ERP components evoked by outcome feedbacks could serve as biomarkers to signal the influence of current outcome evaluation on subsequent decision-making. In this study, 18 adult volunteers participated in a simple monetary gambling task, in which they were asked to choose between two options that differed in risk. Their decisions were immediately followed by outcome presentation. Temporospatial principle component analysis (PCA) was applied to the outcome-onset locked ERPs in the 200-1000 ms time window. The PCA factors that approximated classical ERP components (P2, feedback-related negativity, P3a, and P3b) in terms of time course and scalp distribution were tested for their association with subsequent decision-making strategies. Our results revealed that a fronto-central PCA factor approximating the classical P3a was related to changes of decision-making strategies on subsequent trials. The decision to switch between high- and low-risk options resulted in a larger P3a relative to the decision to retain the same choice. According to the results, we suggest that the amplitude of the fronto-central P3a is an electrophysiological index of the influence of current outcome on subsequent risk decision-making. Furthermore, the ERP source analysis indicated that the activations of the frontopolar cortex and sensorimotor cortex were involved in subsequent changes of strategies, which enriches our understanding of the neural mechanisms of adjusting decision-making strategies based on previous experience. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

Event-related potential studies of outcome processing and feedback-guided learning.

PubMed

San Martín, René

2012-01-01

In order to control behavior in an adaptive manner the brain has to learn how some situations and actions predict positive or negative outcomes. During the last decade cognitive neuroscientists have shown that the brain is able to evaluate and learn from outcomes within a few hundred milliseconds of their occurrence. This research has been primarily focused on the feedback-related negativity (FRN) and the P3, two event-related potential (ERP) components that are elicited by outcomes. The FRN is a frontally distributed negative-polarity ERP component that typically reaches its maximal amplitude 250 ms after outcome presentation and tends to be larger for negative than for positive outcomes. The FRN has been associated with activity in the anterior cingulate cortex (ACC). The P3 (~300-600 ms) is a parietally distributed positive-polarity ERP component that tends to be larger for large magnitude than for small magnitude outcomes. The neural sources of the P3 are probably distributed over different regions of the cortex. This paper examines the theories that have been proposed to explain the functional role of these two ERP components during outcome processing. Special attention is paid to extant literature addressing how these ERP components are modulated by outcome valence (negative vs. positive), outcome magnitude (large vs. small), outcome probability (unlikely vs. likely), and behavioral adjustment. The literature offers few generalizable conclusions, but is beset with a number of inconsistencies across studies. This paper discusses the potential reasons for these inconsistencies and points out some challenges that probably will shape the field over the next decade.

Event-related potential evidence for separable automatic and controlled retrieval processes in proactive interference.

PubMed

Bergström, Zara M; O'Connor, Richard J; Li, Martin K-H; Simons, Jon S

2012-05-21

Interference between competing memories is a major source of retrieval failure, yet, surprisingly little is known about how competitive memory activation arises in the brain. One possibility is that interference during episodic retrieval might be produced by relatively automatic conceptual priming mechanisms that are independent of strategic retrieval processes. Such priming-driven interference might occur when the competing memories have strong pre-existing associations to the retrieval cue. We used ERPs to measure the neural dynamics of retrieval competition, and investigated whether the ERP correlates of interference were affected by varying task demands for selective retrieval. Participants encoded cue words that were presented either two or four times, paired either with the same or different strongly associated words across repetitions. In a subsequent test, participants either selectively recalled each cue's most recent associate, or simply judged how many times a cue had been presented, without requiring selective recall. Interference effects on test performance were only seen in the recall task. In contrast, ERPs during test revealed an early posterior positivity for high interference items that was present in both retrieval tasks. This early ERP effect likely reflects a conceptual priming-related N400 reduction when many associations to a cue were pre-activated. A later parietal positivity resembling the ERP correlate of conscious recollection was found only in the recall task. The results suggest that early effects of proactive interference are relatively automatic and independent of intentional retrieval processes, consistent with suggestions that interference can arise through conceptual priming. Copyright © 2012 Elsevier B.V. All rights reserved.

The role of retrieval mode and retrieval orientation in retrieval practice: insights from comparing recognition memory testing formats and restudying.

PubMed

Gao, Chuanji; Rosburg, Timm; Hou, Mingzhu; Li, Bingbing; Xiao, Xin; Guo, Chunyan

2016-12-01

The effectiveness of retrieval practice for aiding long-term memory, referred to as the testing effect, has been widely demonstrated. However, the specific neurocognitive mechanisms underlying this phenomenon remain unclear. In the present study, we sought to explore the role of pre-retrieval processes at initial testing on later recognition performance by using event-related potentials (ERPs). Subjects studied two lists of words (Chinese characters) and then performed a recognition task or a source memory task, or restudied the word lists. At the end of the experiment, subjects received a final recognition test based on the remember-know paradigm. Behaviorally, initial testing (active retrieval) enhanced memory retention relative to restudying (passive retrieval). The retrieval mode at initial testing was indexed by more positive-going ERPs for unstudied items in the active-retrieval tasks than in passive retrieval from 300 to 900 ms. Follow-up analyses showed that the magnitude of the early ERP retrieval mode effect (300-500 ms) was predictive of the behavioral testing effect later on. In addition, the ERPs for correctly rejected new items during initial testing differed between the two active-retrieval tasks from 500 to 900 ms, and this ERP retrieval orientation effect predicted differential behavioral testing gains between the two active-retrieval conditions. Our findings confirm that initial testing promotes later retrieval relative to restudying, and they further suggest that adopting pre-retrieval processing in the forms of retrieval mode and retrieval orientation might contribute to these memory enhancements.

An electrophysiological index of changes in risk decision-making strategies

PubMed Central

Zhang, Dandan; Gu, Ruolei; Wu, Tingting; Broster, Lucas S.; Luo, Yi; Jiang, Yang; Luo, Yue-jia

2014-01-01

Human decision-making is significantly modulated by previously experienced outcomes. Using event-related potentials (ERPs), we examined whether ERP components evoked by outcome feedbacks could serve as biomarkers to signal the influence of current outcome evaluation on subsequent decision-making. In this study, eighteen adult volunteers participated in a simple monetary gambling task, in which they were asked to choose between two options that differed in risk. Their decisions were immediately followed by outcome presentation. Temporospatial principle component analysis (PCA) was applied to the outcome-onset locked ERPs in the -200 – 1000 ms time window. The PCA factors that approximated classical ERP components (P2, feedback-related negativity, P3a, & P3b) in terms of time course and scalp distribution were tested for their association with subsequent decision-making strategies. Our results revealed that a fronto-central PCA factor approximating the classical P3a was related to changes of decision-making strategies on subsequent trials. The decision to switch between high- and low-risk options resulted in a larger P3a relative to the decision to retain the same choice. According to the results, we suggest the amplitude of the fronto-central P3a is an electrophysiological index of the influence of current outcome on subsequent risk decision-making. Furthermore, the ERP source analysis indicated that the activations of the frontopolar cortex and sensorimotor cortex were involved in subsequent changes of strategies, which enriches our understanding of the neural mechanisms of adjusting decision-making strategies based on previous experience. PMID:23643796

Your brain on bikes: P3, MMN/N2b, and baseline noise while pedaling a stationary bike.

PubMed

Scanlon, Joanna E M; Sieben, Alex J; Holyk, Kevin R; Mathewson, Kyle E

2017-06-01

Increasingly, there is a trend to measure brain activity in more ecologically realistic scenarios. Normally, the confines of the laboratory and sedentary tasks mitigate sources of electrical noise on EEG measurement. Moving EEG outside of the lab requires understanding of the impact of complex movements and activities on traditional EEG and ERP measures. Here, we recorded EEG with active electrodes while participants were either riding or sitting on a stationary bike in an electrical and sound-attenuated chamber in the lab. Participants performed an auditory oddball task, pressing a button when they detected rare target tones in a series of standard frequent tones. We quantified both the levels of spectral, single-trial baseline, and ERP baseline noise, as well as classic MMN/N2b and P3 ERP components measured during both biking and sitting still. We observed slight increases in posterior high frequency noise in the spectra, and increased noise in the baseline period during biking. However, morphologically and topographically similar MMN/N2b and P3 components were measured reliably while both biking and sitting. A quantification of the power to reliably measure ERPs as a function of the number of trials revealed slight increases in the number of trials needed during biking to achieve the same level of power. Taken in sum, our results confirm that classic ERPs can be measured reliably during biking activities in the lab. Future directions will employ these techniques outside the lab in ecologically valid situations. © 2017 Society for Psychophysiological Research.

Plasticity in the adult language system: a longitudinal electrophysiological study on second language learning.

PubMed

Stein, M; Dierks, T; Brandeis, D; Wirth, M; Strik, W; Koenig, T

2006-11-01

Event-related potentials (ERPs) were used to trace changes in brain activity related to progress in second language learning. Twelve English-speaking exchange students learning German in Switzerland were recruited. ERPs to visually presented single words from the subjects' native language (English), second language (German) and an unknown language (Romansh) were measured before (day 1) and after (day 2) 5 months of intense German language learning. When comparing ERPs to German words from day 1 and day 2, we found topographic differences between 396 and 540 ms. These differences could be interpreted as a latency shift indicating faster processing of German words on day 2. Source analysis indicated that the topographic differences were accounted for by shorter activation of left inferior frontal gyrus (IFG) on day 2. In ERPs to English words, we found Global Field Power differences between 472 and 644 ms. This may due to memory traces related to English words being less easily activated on day 2. Alternatively, it might reflect the fact that--with German words becoming familiar on day 2--English words loose their oddball character and thus produce a weaker P300-like effect on day 2. In ERPs to Romansh words, no differences were observed. Our results reflect plasticity in the neuronal networks underlying second language acquisition. They indicate that with a higher level of second language proficiency, second language word processing is faster and requires shorter frontal activation. Thus, our results suggest that the reduced IFG activation found in previous fMRI studies might not reflect a generally lower activation but rather a shorter duration of activity.

Electrophysiological evidence for separation between human face and non-face object processing only in the right hemisphere.

PubMed

Niina, Megumi; Okamura, Jun-ya; Wang, Gang

2015-10-01

Scalp event-related potential (ERP) studies have demonstrated larger N170 amplitudes when subjects view faces compared to items from object categories. Extensive attempts have been made to clarify face selectivity and hemispheric dominance for face processing. The purpose of this study was to investigate hemispheric differences in N170s activated by human faces and non-face objects, as well as the extent of overlap of their sources. ERP was recorded from 20 subjects while they viewed human face and non-face images. N170s obtained during the presentation of human faces appeared earlier and with larger amplitude than for other category images. Further source analysis with a two-dipole model revealed that the locations of face and object processing largely overlapped in the left hemisphere. Conversely, the source for face processing in the right hemisphere located more anterior than the source for object processing. The results suggest that the neuronal circuits for face and object processing are largely shared in the left hemisphere, with more distinct circuits in the right hemisphere. Copyright © 2015 Elsevier B.V. All rights reserved.

Modulations of 'late' event-related brain potentials in humans by dynamic audiovisual speech stimuli.

PubMed

Lebib, Riadh; Papo, David; Douiri, Abdel; de Bode, Stella; Gillon Dowens, Margaret; Baudonnière, Pierre-Marie

2004-11-30

Lipreading reliably improve speech perception during face-to-face conversation. Within the range of good dubbing, however, adults tolerate some audiovisual (AV) discrepancies and lipreading, then, can give rise to confusion. We used event-related brain potentials (ERPs) to study the perceptual strategies governing the intermodal processing of dynamic and bimodal speech stimuli, either congruently dubbed or not. Electrophysiological analyses revealed that non-coherent audiovisual dubbings modulated in amplitude an endogenous ERP component, the N300, we compared to a 'N400-like effect' reflecting the difficulty to integrate these conflicting pieces of information. This result adds further support for the existence of a cerebral system underlying 'integrative processes' lato sensu. Further studies should take advantage of this 'N400-like effect' with AV speech stimuli to open new perspectives in the domain of psycholinguistics.

The political (and physiological) divide: Political orientation, performance monitoring, and the anterior cingulate response.

PubMed

Weissflog, Meghan; Choma, Becky L; Dywan, Jane; van Noordt, Stefon J R; Segalowitz, Sidney J

2013-01-01

Our goal was to test a model of sociopolitical attitudes that posits a relationship between individual differences in liberal versus conservative political orientation and differential levels of anterior cingulate cortex (ACC) responsivity. We recorded event-related potentials (ERPs) while participants who varied along a unidimensional liberal-conservative continuum engaged in a standard Go/NoGo task. We also measured component attitudes of political orientation in the form of traditionalism (degree of openness to social change) and egalitarianism (a preference for social equality). Generally, participants who reported a more liberal political orientation made fewer errors and produced larger ACC-generated ERPs (the error-related negativity, or ERN and the NoGo N2). This ACC activation, especially as indicated by a larger NoGo N2, was most strongly associated with greater preference for social equality. Performance accuracy, however, was most strongly associated with greater openness to social change. These data are consistent with a social neuroscience view that sociopolitical attitudes are related to aspects of neurophysiological responsivity. They also indicate that a bidimensional model of political orientation can enhance our interpretation of the nature of these associations.

Individual differences in cardiac vagal tone are associated with differential neural responses to facial expressions at different spatial frequencies: an ERP and sLORETA study.

PubMed

Park, Gewnhi; Moon, Eunok; Kim, Do-Won; Lee, Seung-Hwan

2012-12-01

A previous study has shown that greater cardiac vagal tone, reflecting effective self-regulatory capacity, was correlated with superior visual discrimination of fearful faces at high spatial frequency Park et al. (Biological Psychology 90:171-178, 2012b). The present study investigated whether individual differences in cardiac vagal tone (indexed by heart rate variability) were associated with different event-related brain potentials (ERPs) in response to fearful and neutral faces. Thirty-six healthy participants discriminated the emotion of fearful and neutral faces at broad, high, and low spatial frequencies, while ERPs were recorded. Participants with low resting heart rate variability-characterized by poor functioning of regulatory systems-exhibited significantly greater N200 activity in response to fearful faces at low spatial frequency and greater LPP responses to neutral faces at high spatial frequency. Source analyses-estimated by standardized low-resolution brain electromagnetic tomography (sLORETA)-tended to show that participants with low resting heart rate variability exhibited increased source activity in visual areas, such as the cuneus and the middle occipital gyrus, as compared with participants with high resting heart rate variability. The hyperactive neural activity associated with low cardiac vagal tone may account for hypervigilant response patterns and emotional dysregulation, which heightens the risk of developing physical and emotional problems.

Prosocial attitudes and empathic behavior in emotional positive versus negative situations: brain response (ERPs) and source localization (LORETA) analysis.

PubMed

Balconi, Michela; Canavesio, Ylenia

2013-03-01

The present research firstly investigated the neural correlates (ERPs, event-related potentials) of attitudes to engage in prosocial-helping behaviors, and secondly, it analyzed the relation between these brain-based potentials and personal profile (high vs. low empathic profile). It was considered the subjects' behavior in response to specific emotional situations (positive vs. negative) in case it was required a possible prosocial intervention. Thirty-one subjects were invited to empathize with the emotional contexts (videotapes that reproduced two person's exchanges) and to decide whether to intervene or not to support these persons. BEES questionnaire for empathic behavior was submitted to the subjects after the experimental session. ERP acquisition and LORETA source analysis revealed a negative ongoing deflection (N200 effect) more prefrontally distributed (dorsolateral prefrontal cortex) in response to prosocial intervention options mainly for negative and positive contexts. Moreover, a significant positive correlation was found between high-empathic profiles, intervention behaviors (higher frequency of interventions) and N200 amplitude (higher peak). These results highlight the role of emotions in prosocial behavior, since the N200 effect was considered a marker of the emotional significance of the interpersonal situation. Secondly, the empathic trait may explain the prosocial decisional processes: Higher empathic trait contributes to induce subject's intervention behavior which in turn appears to be directly related to the cortical responsiveness within the prefrontal areas.

MAO-A Phenotype Effects Response Sensitivity and the Parietal Old/New Effect during Recognition Memory

PubMed Central

Ross, Robert S.; Smolen, Andrew; Curran, Tim; Nyhus, Erika

2018-01-01

A critical problem for developing personalized treatment plans for cognitive disruptions is the lack of understanding how individual differences influence cognition. Recognition memory is one cognitive ability that varies from person to person and that variation may be related to different genetic phenotypes. One gene that may impact recognition memory is the monoamine oxidase A gene (MAO-A), which influences the transcription rate of MAO-A. Examination of how MAO-A phenotypes impact behavioral and event-related potentials (ERPs) correlates of recognition memory may help explain individual differences in recognition memory performance. Therefore, the current study uses electroencephalography (EEG) in combination with genetic phenotyping of the MAO-A gene to determine how well-characterized ERP components of recognition memory, the early frontal old/new effect, left parietal old/new effect, late frontal old/new effect, and the late posterior negativity (LPN) are impacted by MAO-A phenotype during item and source memory. Our results show that individuals with the MAO-A phenotype leading to increased transcription have lower response sensitivity during both item and source memory. Additionally, during item memory the left parietal old/new effect is not present due to increased ERP amplitude for correct rejections. The results suggest that MAO-A phenotype changes EEG correlates of recognition memory and influences how well individuals differentiate between old and new items. PMID:29487517

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.

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.

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…

Predicting Clinical Gains and Side Effects of Stimulant Medication in Pediatric Attention-Deficit/Hyperactivity Disorder by Combining Measures From qEEG and ERPs in a Cued GO/NOGO Task.

PubMed

Ogrim, Geir; Kropotov, Juri D

2018-06-01

The study aim was to develop 2 scales: predicting clinical gains and risk of acute side effects of stimulant medication in pediatric attention-deficit/hyperactivity disorder (ADHD), combining measures from EEG spectra, event-related potentials (ERPs), and a cued visual GO/NOGO task. Based on 4-week systematic medication trials, 87 ADHD patients aged 8 to 17 years were classified as responders (REs, n = 62) or non-REs (n = 25), and belonging to the side effects (SEs, n = 42) or no-SEs (n = 45) groups. Before starting the trial, a 19-channel EEG was registered twice: Test 1 (T1) without medication and T2 on a single dose of stimulant medication a few days before the trial. EEG was registered T1 and T2: 3 minutes eyes-closed, 3 minutes eyes-open, and 20 minutes cued GO/NOGO. EEG spectra, ERPs, omissions, commissions, reaction time (RT), and RT variability were computed. Groups were compared at T1 and T2 on quantitative EEG (qEEG), ERPs and behavioral parameters; effect sizes ( d) were estimated. Variables with d > 0.5 were converted to quartiles, multiplied by corresponding d, and summed to obtain 2 global scales. Six variables differed significantly between REs and non-REs (T1: theta/alpha ratio, P3NOGO amplitude. Differences T2-T1: Omissions, RT variability, P3NOGO, contingent negative variation [CNV]). The global scale d was 1.86. Accuracy (receiver operating characteristic) was 0.92. SEs and no-SEs differed significantly on 4 variables. (T1: RT, T2: novelty component and alpha peak frequency, and RT changes. Global scale d = 1.08 and accuracy = 0.78. Gains and side effects of stimulants in pediatric ADHD can be predicted with high accuracy by combining EEG spectra, ERPs, and behavior from baseline and single-dose tests. ClinicalTrials.gov identifier: NCT02695355.

Electrophysiological quantification of underlying mechanism of decision making from auto dealers advertisement - A neuromarketing research

NASA Astrophysics Data System (ADS)

Samsuri, Norlyiana; Reza, Faruque; Begum, Tahamina; Yusoff, Nasir; Idris, Badrisyah; Omar, Hazim; Isa, Salmi Mohd

2016-10-01

This study focused on which display design of advertisement that would be able to attract most attention by measuring cognitive response and gaze behavior. Total of 15 subjects were recruited from USM undergraduate medical students. The event related potential (ERP) as a cognitive response during viewing different display design were recorded from 17 electrode sites using 128 electrode sensors net which was applied on the subject's scalp according to the 10-20 international electrode placement system. The amplitude of the evoked N100 and P300 ERP components were identified. To determine the statistical significance, amplitude data were analyzed using one way ANOVA test and reaction time was analyzed using Independent t-test. Two out of the 15 subjects participated in the ERP recording in order to measure the fixation duration, pupil size and attention maps of eye movement as a gaze behavioral response to the different display design using Eye Tracking. The ERP and the gaze behavior results were consistent. Higher amplitudes of the N100 and the P300 ERP components during the RLG view proved that participants had larger visual selective attention and visual cognitive processing during visual presentation of the RLG view. Visual interpretation of the attention map together with the fixation duration and the pupil size of gaze behavior data from two case studies revealed that the RLG view attracted more attention than its counterpart. In regards to color as a confounder, gaze performance data from two cases opened an interesting finding is that both subjects showed common interest in red color during both the LLG and the RLG view, indicating color may play a different role in the display design. The finding of this research has important information for the marketers to design their advertisement making it cost-effective and limited space advertising. And on that case, RLG view is the most prioritize display design.

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…

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

Women are better at seeing faces where there are none: an ERP study of face pareidolia

PubMed Central

Galli, Jessica

2016-01-01

Event-related potentials (ERPs) were recorded in 26 right-handed students while they detected pictures of animals intermixed with those of familiar objects, faces and faces-in-things (FITs). The face-specific N170 ERP component over the right hemisphere was larger in response to faces and FITs than to objects. The vertex positive potential (VPP) showed a difference in FIT encoding processes between males and females at frontal sites; while for men, the FIT stimuli elicited a VPP of intermediate amplitude (between that for faces and objects), for women, there was no difference in VPP responses to faces or FITs, suggesting a marked anthropomorphization of objects in women. SwLORETA source reconstructions carried out to estimate the intracortical generators of ERPs in the 150–190 ms time window showed how, in the female brain, FIT perception was associated with the activation of brain areas involved in the affective processing of faces (right STS, BA22; posterior cingulate cortex, BA22; and orbitofrontal cortex, BA10) in addition to regions linked to shape processing (left cuneus, BA18/30). Conversely, in the men, the activation of occipito/parietal regions was prevalent, with a considerably smaller activation of BA10. The data suggest that the female brain is more inclined to anthropomorphize perfectly real objects compared to the male brain. PMID:27217120

Electrocortical Reactivity During Self-referential Processing in Female Youth With Borderline Personality Disorder.

PubMed

Auerbach, Randy P; Tarlow, Naomi; Bondy, Erin; Stewart, Jeremy G; Aguirre, Blaise; Kaplan, Cynthia; Yang, Wenhui; Pizzagalli, Diego A

2016-07-01

Borderline personality disorder (BPD) is debilitating, and theoretical models have postulated that cognitive-affective biases contribute to the onset and maintenance of BPD symptoms. Despite advances, our understanding of BPD pathophysiology in youth is limited. The present study used event-related potentials (ERPs) to identify cognitive-affective processes that underlie negative self-referential processing in BPD youth. Healthy females ( n = 33) and females with BPD ( n = 26) 13 to 22 years of age completed a self-referential encoding task while 128-channel electroencephalography data were recorded to examine early (i.e., P1 and P2) and late (late positive potential [LPP]) ERP components. Whole-brain standardized low-resolution electromagnetic tomography explored intracortical sources underlying significant scalp ERP effects. Compared to healthy females, participants with BPD endorsed, recalled, and recognized fewer positive and more negative words. Moreover, unlike the healthy group, females with BPD had faster reaction times to endorse negative versus positive words. In the scalp ERP analyses, the BPD group had greater P2 and late LPP positivity to negative as opposed to positive words. For P2 and late LPP, whole-brain standardized low-resolution electromagnetic tomography analyses suggested that females with BPD overrecruit frontolimbic circuitry in response to negative stimuli. Collectively, these findings show that females with BPD process negative self-relevant information differently than healthy females. Clinical implications and future directions are discussed.

Electrocortical Reactivity During Self-referential Processing in Female Youth With Borderline Personality Disorder

PubMed Central

Auerbach, Randy P.; Tarlow, Naomi; Bondy, Erin; Stewart, Jeremy G.; Aguirre, Blaise; Kaplan, Cynthia; Yang, Wenhui; Pizzagalli, Diego A.

2016-01-01

BACKGROUND Borderline personality disorder (BPD) is debilitating, and theoretical models have postulated that cognitive-affective biases contribute to the onset and maintenance of BPD symptoms. Despite advances, our understanding of BPD pathophysiology in youth is limited. The present study used event-related potentials (ERPs) to identify cognitive-affective processes that underlie negative self-referential processing in BPD youth. METHODS Healthy females (n = 33) and females with BPD (n = 26) 13 to 22 years of age completed a self-referential encoding task while 128-channel electroencephalography data were recorded to examine early (i.e., P1 and P2) and late (late positive potential [LPP]) ERP components. Whole-brain standardized low-resolution electromagnetic tomography explored intracortical sources underlying significant scalp ERP effects. RESULTS Compared to healthy females, participants with BPD endorsed, recalled, and recognized fewer positive and more negative words. Moreover, unlike the healthy group, females with BPD had faster reaction times to endorse negative versus positive words. In the scalp ERP analyses, the BPD group had greater P2 and late LPP positivity to negative as opposed to positive words. For P2 and late LPP, whole-brain standardized low-resolution electromagnetic tomography analyses suggested that females with BPD overrecruit frontolimbic circuitry in response to negative stimuli. CONCLUSIONS Collectively, these findings show that females with BPD process negative self-relevant information differently than healthy females. Clinical implications and future directions are discussed. PMID:28626812

Event-related brain potentials and the study of reward processing: Methodological considerations.

PubMed

Krigolson, Olave E

2017-11-14

There is growing interest in using electroencephalography and specifically the event-related brain potential (ERP) methodology to study human reward processing. Since the discovery of the feedback related negativity (Miltner et al., 1997) and the development of theories associating the feedback related negativity and more recently the reward positivity with reinforcement learning, midbrain dopamine function, and the anterior cingulate cortex (i.e., Holroyd and Coles, 2002) researchers have used the ERP methodology to probe the neural basis of reward learning in humans. However, examination of the feedback related negativity and the reward positivity cannot be done without an understanding of some key methodological issues that must be taken into account when using ERPs and examining these ERP components. For example, even the component name - the feedback related negativity - is a source of debate within the research community as some now strongly feel that the component should be named the reward positivity (Proudfit, 2015). Here, ten key methodological issues are discussed - confusion in component naming, the reward positivity, component identification, peak quantification and the use of difference waveforms, frequency (the N200) and component contamination (the P300), the impact of feedback timing, action, and task learnability, and how learning results in changes in the amplitude of the feedback-related negativity/reward positivity. The hope here is to not provide a definitive approach for examining the feedback related negativity/reward positivity, but instead to outline the key issues that must be taken into account when examining this component to assist researchers in their study of human reward processing with the ERP methodology. Copyright © 2017 Elsevier B.V. All rights reserved.

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…

[Neurophysiological correlates of learning disabilities in Japan].

PubMed

Miyao, M

1999-05-01

In the present study, we developed a new event-related potentials (ERPs) stimulator system applicable to simultaneous audio visual stimuli, and tested it clinically on healthy adults and patients with learning disabilities (LD), using Japanese language task stimuli: hiragana letters, kanji letters, and kanji letters with spoken words. (1) The origins of the P300 component were identified in these tasks. The sources in the former two tasks were located in different areas. In the simultaneous task stimuli, a combination of the two P300 sources was observed with dominance in the left posterior inferior temporal area. (2) In patients with learning disabilities, those with reading and writing disability showed low amplitudes in the left hemisphere in response to visual language task stimuli with kanji and hiragana letters, in contrast to healthy children and LD patients with arithmetic disability. (3) To evaluate the effect of methylphenidate (10 mg) on ADD, paired-associate ERPs were recorded. Methylphenidate increased the amplitude of P300.

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.

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.

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.

Comparison of spatiotemporal cortical activation pattern during visual perception of Korean, English, Chinese words: an event-related potential study.

PubMed

Kim, Kyung Hwan; Kim, Ja Hyun

2006-02-20

The aim of this study was to compare spatiotemporal cortical activation patterns during the visual perception of Korean, English, and Chinese words. The comparison of these three languages offers an opportunity to study the effect of written forms on cortical processing of visually presented words, because of partial similarity/difference among words of these languages, and the familiarity of native Koreans with these three languages at the word level. Single-character words and pictograms were excluded from the stimuli in order to activate neuronal circuitries that are involved only in word perception. Since a variety of cerebral processes are sequentially evoked during visual word perception, a high-temporal resolution is required and thus we utilized event-related potential (ERP) obtained from high-density electroencephalograms. The differences and similarities observed from statistical analyses of ERP amplitudes, the correlation between ERP amplitudes and response times, and the patterns of current source density, appear to be in line with demands of visual and semantic analysis resulting from the characteristics of each language, and the expected task difficulties for native Korean subjects.

Evaluative conditioning of positive and negative valence affects P1 and N1 in verbal processing.

PubMed

Kuchinke, Lars; Fritsch, Nathalie; Müller, Christina J

2015-10-22

The present study examined the effect of contextual learning on the neural processing of previously meaningless pseudowords. During an evaluative conditioning session on 5 consecutive days, participants learned to associate 120 pseudowords with either positive, neutral or negative pictures. In a second session, participants were presented all conditioned pseudowords again together with 40 new pseudowords in a recognition memory task while their event-related potentials (ERPs) were recorded. The behavioral data confirm successful learning of pseudoword valence. At the neural level, early modulations of the ERPs are visible at the P1 and the N1 components discriminating between positively and negatively conditioned pseudowords. Differences to new pseudowords were visible at later processing stages as indicated by modulations of the LPC. These results support a contextual learning hypothesis that is able to explain very early emotional ERP modulations in visual word recognition. Source localization indicates a role of medial-frontal brain regions as a likely origin of these early valence discrimination signals which are discussed to promote top-down signals to sensory processing. Copyright © 2015. Published by Elsevier B.V.

Enhanced attention-dependent activity in the auditory cortex of older musicians.

PubMed

Zendel, Benjamin Rich; Alain, Claude

2014-01-01

Musical training improves auditory processing abilities, which correlates with neuro-plastic changes in exogenous (input-driven) and endogenous (attention-dependent) components of auditory event-related potentials (ERPs). Evidence suggests that musicians, compared to non-musicians, experience less age-related decline in auditory processing abilities. Here, we investigated whether lifelong musicianship mitigates exogenous or endogenous processing by measuring auditory ERPs in younger and older musicians and non-musicians while they either attended to auditory stimuli or watched a muted subtitled movie of their choice. Both age and musical training-related differences were observed in the exogenous components; however, the differences between musicians and non-musicians were similar across the lifespan. These results suggest that exogenous auditory ERPs are enhanced in musicians, but decline with age at the same rate. On the other hand, attention-related activity, modeled in the right auditory cortex using a discrete spatiotemporal source analysis, was selectively enhanced in older musicians. This suggests that older musicians use a compensatory strategy to overcome age-related decline in peripheral and exogenous processing of acoustic information. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

Learning from label proportions in brain-computer interfaces: Online unsupervised learning with guarantees.

PubMed

Hübner, David; Verhoeven, Thibault; Schmid, Konstantin; Müller, Klaus-Robert; Tangermann, Michael; Kindermans, Pieter-Jan

2017-01-01

Using traditional approaches, a brain-computer interface (BCI) requires the collection of calibration data for new subjects prior to online use. Calibration time can be reduced or eliminated e.g., by subject-to-subject transfer of a pre-trained classifier or unsupervised adaptive classification methods which learn from scratch and adapt over time. While such heuristics work well in practice, none of them can provide theoretical guarantees. Our objective is to modify an event-related potential (ERP) paradigm to work in unison with the machine learning decoder, and thus to achieve a reliable unsupervised calibrationless decoding with a guarantee to recover the true class means. We introduce learning from label proportions (LLP) to the BCI community as a new unsupervised, and easy-to-implement classification approach for ERP-based BCIs. The LLP estimates the mean target and non-target responses based on known proportions of these two classes in different groups of the data. We present a visual ERP speller to meet the requirements of LLP. For evaluation, we ran simulations on artificially created data sets and conducted an online BCI study with 13 subjects performing a copy-spelling task. Theoretical considerations show that LLP is guaranteed to minimize the loss function similar to a corresponding supervised classifier. LLP performed well in simulations and in the online application, where 84.5% of characters were spelled correctly on average without prior calibration. The continuously adapting LLP classifier is the first unsupervised decoder for ERP BCIs guaranteed to find the optimal decoder. This makes it an ideal solution to avoid tedious calibration sessions. Additionally, LLP works on complementary principles compared to existing unsupervised methods, opening the door for their further enhancement when combined with LLP.

Learning from label proportions in brain-computer interfaces: Online unsupervised learning with guarantees

PubMed Central

Verhoeven, Thibault; Schmid, Konstantin; Müller, Klaus-Robert; Tangermann, Michael; Kindermans, Pieter-Jan

2017-01-01

Objective Using traditional approaches, a brain-computer interface (BCI) requires the collection of calibration data for new subjects prior to online use. Calibration time can be reduced or eliminated e.g., by subject-to-subject transfer of a pre-trained classifier or unsupervised adaptive classification methods which learn from scratch and adapt over time. While such heuristics work well in practice, none of them can provide theoretical guarantees. Our objective is to modify an event-related potential (ERP) paradigm to work in unison with the machine learning decoder, and thus to achieve a reliable unsupervised calibrationless decoding with a guarantee to recover the true class means. Method We introduce learning from label proportions (LLP) to the BCI community as a new unsupervised, and easy-to-implement classification approach for ERP-based BCIs. The LLP estimates the mean target and non-target responses based on known proportions of these two classes in different groups of the data. We present a visual ERP speller to meet the requirements of LLP. For evaluation, we ran simulations on artificially created data sets and conducted an online BCI study with 13 subjects performing a copy-spelling task. Results Theoretical considerations show that LLP is guaranteed to minimize the loss function similar to a corresponding supervised classifier. LLP performed well in simulations and in the online application, where 84.5% of characters were spelled correctly on average without prior calibration. Significance The continuously adapting LLP classifier is the first unsupervised decoder for ERP BCIs guaranteed to find the optimal decoder. This makes it an ideal solution to avoid tedious calibration sessions. Additionally, LLP works on complementary principles compared to existing unsupervised methods, opening the door for their further enhancement when combined with LLP. PMID:28407016

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.

Combined ICA-LORETA analysis of mismatch negativity.

PubMed

Marco-Pallarés, J; Grau, C; Ruffini, G

2005-04-01

A major challenge for neuroscience is to map accurately the spatiotemporal patterns of activity of the large neuronal populations that are believed to underlie computing in the human brain. To study a specific example, we selected the mismatch negativity (MMN) brain wave (an event-related potential, ERP) because it gives an electrophysiological index of a "primitive intelligence" capable of detecting changes, even abstract ones, in a regular auditory pattern. ERPs have a temporal resolution of milliseconds but appear to result from mixed neuronal contributions whose spatial location is not fully understood. Thus, it is important to separate these sources in space and time. To tackle this problem, a two-step approach was designed combining the independent component analysis (ICA) and low-resolution tomography (LORETA) algorithms. Here we implement this approach to analyze the subsecond spatiotemporal dynamics of MMN cerebral sources using trial-by-trial experimental data. We show evidence that a cerebral computation mechanism underlies MMN. This mechanism is mediated by the orchestrated activity of several spatially distributed brain sources located in the temporal, frontal, and parietal areas, which activate at distinct time intervals and are grouped in six main statistically independent components.

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.

From upright to upside-down presentation: A spatio-temporal ERP study of the parametric effect of rotation on face and house processing

PubMed Central

Jemel, Boutheina; Coutya, Julie; Langer, Caroline; Roy, Sylvain

2009-01-01

Background While there is a general agreement that picture-plane inversion is more detrimental to face processing than to other seemingly complex visual objects, the origin of this effect is still largely debatable. Here, we address the question of whether face inversion reflects a quantitative or a qualitative change in processing mode by investigating the pattern of event-related potential (ERP) response changes with picture plane rotation of face and house pictures. Thorough analyses of topographical (Scalp Current Density maps, SCD) and dipole source modeling were also conducted. Results We find that whilst stimulus orientation affected in a similar fashion participants' response latencies to make face and house decisions, only the ERPs in the N170 latency range were modulated by picture plane rotation of faces. The pattern of N170 amplitude and latency enhancement to misrotated faces displayed a curvilinear shape with an almost linear increase for rotations from 0° to 90° and a dip at 112.5° up to 180° rotations. A similar discontinuity function was also described for SCD occipito-temporal and temporal current foci with no topographic distribution changes, suggesting that upright and misrotated faces activated similar brain sources. This was confirmed by dipole source analyses showing the involvement of bilateral sources in the fusiform and middle occipital gyri, the activity of which was differentially affected by face rotation. Conclusion Our N170 findings provide support for both the quantitative and qualitative accounts for face rotation effects. Although the qualitative explanation predicted the curvilinear shape of N170 modulations by face misrotations, topographical and source modeling findings suggest that the same brain regions, and thus the same mechanisms, are probably at work when processing upright and rotated faces. Taken collectively, our results indicate that the same processing mechanisms may be involved across the whole range of face orientations, but would operate in a non-linear fashion. Finally, the response tuning of the N170 to rotated faces extends previous reports and further demonstrates that face inversion affects perceptual analyses of faces, which is reflected within the time range of the N170 component. PMID:19691846

From upright to upside-down presentation: a spatio-temporal ERP study of the parametric effect of rotation on face and house processing.

PubMed

Jemel, Boutheina; Coutya, Julie; Langer, Caroline; Roy, Sylvain

2009-08-19

While there is a general agreement that picture-plane inversion is more detrimental to face processing than to other seemingly complex visual objects, the origin of this effect is still largely debatable. Here, we address the question of whether face inversion reflects a quantitative or a qualitative change in processing mode by investigating the pattern of event-related potential (ERP) response changes with picture plane rotation of face and house pictures. Thorough analyses of topographical (Scalp Current Density maps, SCD) and dipole source modeling were also conducted. We find that whilst stimulus orientation affected in a similar fashion participants' response latencies to make face and house decisions, only the ERPs in the N170 latency range were modulated by picture plane rotation of faces. The pattern of N170 amplitude and latency enhancement to misrotated faces displayed a curvilinear shape with an almost linear increase for rotations from 0 degrees to 90 degrees and a dip at 112.5 degrees up to 180 degrees rotations. A similar discontinuity function was also described for SCD occipito-temporal and temporal current foci with no topographic distribution changes, suggesting that upright and misrotated faces activated similar brain sources. This was confirmed by dipole source analyses showing the involvement of bilateral sources in the fusiform and middle occipital gyri, the activity of which was differentially affected by face rotation. Our N170 findings provide support for both the quantitative and qualitative accounts for face rotation effects. Although the qualitative explanation predicted the curvilinear shape of N170 modulations by face misrotations, topographical and source modeling findings suggest that the same brain regions, and thus the same mechanisms, are probably at work when processing upright and rotated faces. Taken collectively, our results indicate that the same processing mechanisms may be involved across the whole range of face orientations, but would operate in a non-linear fashion. Finally, the response tuning of the N170 to rotated faces extends previous reports and further demonstrates that face inversion affects perceptual analyses of faces, which is reflected within the time range of the N170 component.

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...

Evaluation of the effectiveness of neurofeedback in the reduction of Posttraumatic stress disorder (PTSD) in a patient following high-voltage electric shock with the use of ERPs.

PubMed

Chrapusta, Anna; Pąchalska, Maria; Wilk-Frańczuk, Magdalena; Starczyńska, Małgorzata; Kropotov, Juri D

2015-01-01

The aim of our research was an evaluation of the effectiveness of neurofeedback in reducing the symptoms of Post-trauma stress disorder (PTSD), which had developed as a result of a high-voltage electric burn to the head. Quantitative EEG (QEEG) and Event related potentials (ERPs) were utilised in the evaluation. A 21-year-old patient, experienced 4(th) degree burns to his head as a result of a high-voltage electric burn. The patient was repeatedly operated on and despite the severity of the injuries was to recover. However the patient complained of flashbacks, difficulties with sleeping as well as an inability to continue work in his given profession. Specialist tests were to show the presence within him of PTSD. As a result of which the patient was provided with neurofeedback therapy. The effectiveness of this therapy in the reduction (eradication) of the symptoms of PTSD were evaluated through the utilisation of qantitative eeg (Qeeg) and event related potentials (ERPs). It was found that in the first examination that ERPs display the most significant deviations from the reference in the two components: (1) the one component is generated within the cingulate cortex. The pattern of its deviation from the norms is similar to that found in a group of OCD patients. In contrast to healthy subjects the component repeats itself twice; (2) the second component is generated in the medial prefrontal cortex. Its pattern (neuromarker) is similar to that found in PTSD patients. There is a delay in the late part of the component, which probably reflects the flashbacks. In the second examination, after neurofeedback training, the ERPs were similar to the norm. The patient returned to work. Chronic PTSD developed within the patient as a result of a high-voltage electric burn. The application of a method of therapy (neurofeedback) resulted in the withdrawal of the syndrome symptoms. ERPs in a GO/NOGO task can be used to plan neurofeedback and in the assessment of functional brain changes induced by neurotherapeutic programmes. Funds Collection: Private sources.

Electrophysiological Evidence for Late Maturation of Strategic Episodic Retrieval Processes

ERIC Educational Resources Information Center

Sprondel, Volker; Kipp, Kerstin H.; Mecklinger, Axel

2012-01-01

Improvement in source memory performance throughout development is thought to be mediated by strategic processes that facilitate the retrieval of task-relevant information. Using event-related potentials (ERPs), we examined developmental changes in these processes during adolescence. Adolescents (13-14 years) and adults (19-29 years) completed a…

The more you ignore me the closer I get: An ERP study of evaluative priming.

PubMed

Gibbons, Henning; Bachmann, Olga; Stahl, Jutta

2014-12-01

We used event-related brain potentials (ERPs) to investigate the various mental processes contributing to evaluative priming-that is, more positive judgments for targets preceded by affectively positive, as opposed to negative, prime stimuli. To ensure ecological validity, we employed a priori meaningful landscape pictures as targets and emotional adjectives as visual primes and presented both primes and targets for relatively long durations (>1 s). Prime-related lateralized readiness potentials (LRPs) revealed response priming as one source of the significant evaluative priming effect. On the other hand, greater right-frontal positive slow wave in the ERP for pictures following negative, as compared with positive, primes indicated altered impression formation, thus supporting automatic spreading activation and/or affect misattribution accounts. Moreover, target LRPs suggested conscious counter-control to reduce the evaluative priming net effect. Finally, when comparing prime ERPs for two groups of participants showing strong versus weak evaluative priming, we found strong evidence for the role of depth of prime processing: In the weak-effect group, prime words evoked an increased visual P1/N1 complex, a larger posterior P2 component, and a greater left-parietal processing negativity presumably reflecting semantic processing. By contrast, a larger medial-frontal P2/N2 complex in the strong-effect group suggested top-down inhibition of the prime's emotional content. Thus, trying to ignore the primes can actually increase, rather than decrease, the evaluative priming effect.

Women are better at seeing faces where there are none: an ERP study of face pareidolia.

PubMed

Proverbio, Alice M; Galli, Jessica

2016-09-01

Event-related potentials (ERPs) were recorded in 26 right-handed students while they detected pictures of animals intermixed with those of familiar objects, faces and faces-in-things (FITs). The face-specific N170 ERP component over the right hemisphere was larger in response to faces and FITs than to objects. The vertex positive potential (VPP) showed a difference in FIT encoding processes between males and females at frontal sites; while for men, the FIT stimuli elicited a VPP of intermediate amplitude (between that for faces and objects), for women, there was no difference in VPP responses to faces or FITs, suggesting a marked anthropomorphization of objects in women. SwLORETA source reconstructions carried out to estimate the intracortical generators of ERPs in the 150-190 ms time window showed how, in the female brain, FIT perception was associated with the activation of brain areas involved in the affective processing of faces (right STS, BA22; posterior cingulate cortex, BA22; and orbitofrontal cortex, BA10) in addition to regions linked to shape processing (left cuneus, BA18/30). Conversely, in the men, the activation of occipito/parietal regions was prevalent, with a considerably smaller activation of BA10. The data suggest that the female brain is more inclined to anthropomorphize perfectly real objects compared to the male brain. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

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.

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.

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.

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.

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

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.

Key elements of successful care process of patients with heart symptoms in an emergency care - could an ERP system help?

PubMed

Kontio, Elina; Korvenranta, Heikki; Lundgren-Laine, Heljä; Salanterä, Sanna

2009-01-01

The aim of the study was to identify key elements of successful care process of patients with heart symptoms from the nursing management viewpoint in an emergency care. Through these descriptions, we aimed at identifying possibilities for using enterprise resource planning (ERP) systems to support decision making in emergency care. Hospitals are increasingly moving to process-based workings and at the same time new information system in healthcare are developed and therefore it is essential to understand the strengths and weaknesses of current processes better. A qualitative descriptive design using critical incident technique was employed. Critical Incidents were collected with an open-ended questionnaire. The sample (n=50), 13 head nurses and 37 registered nurses, was purposeful selected from three acute hospitals in southern Finland. The process of patients with heart symptoms in emergency care was described. We identified three competence categories where special focus should be placed to achieve successful process of patients with heart symptoms: process-oriented competencies, personal/management competencies and logistics oriented competencies. Improvement of decision making requires that the care processes are defined and modeled. The research showed that there are several happenings in emergency care where an ERP system could help and support decision making. These happenings can be categorized in two groups: 1) administrative related happenings and 2) patient processes related happenings.

Early Neural Markers of Implicit Attitudes: N170 Modulated by Intergroup and Evaluative Contexts in IAT.

PubMed

Ibáñez, Agustín; Gleichgerrcht, Ezequiel; Hurtado, Esteban; González, Ramiro; Haye, Andrés; Manes, Facundo F

2010-01-01

The Implicit Association Test (IAT) is the most popular measure to evaluate implicit attitudes. Nevertheless, its neural correlates are not yet fully understood. We examined event related potentials (ERPs) in response to face- and word processing while indigenous and non-indigenous participants performed an IAT displaying faces (ingroup and outgroup members) and words (positive and negative valence) as targets of category judgments. The N170 component was modulated by valence of words and by ingroup/outgroup face categorization. Contextual effects (face-words implicitly associated in the task) had an influence on the N170 amplitude modulation. On the one hand, in face categorization, right N170 showed differences according to the association between social categories of faces and affective valence of words. On the other, in word categorization, left N170 presented a similar modulation when the task implied a negative-valence associated with ingroup faces. Only indigenous participants showed a significant IAT effect and N170 differences. Our results demonstrate an early ERP blending of stimuli processing with both intergroup and evaluative contexts, suggesting an integration of contextual information related to intergroup attitudes during the early stages of word and face processing. To our knowledge, this is the first report of early ERPs during an ethnicity IAT, opening a new branch of exchange between social neuroscience and social psychology of attitudes.

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.

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...

Determination of Earth rotation by the combination of data from different space geodetic systems

NASA Technical Reports Server (NTRS)

Archinal, Brent Allen

1987-01-01

Formerly, Earth Rotation Parameters (ERP), i.e., polar motion and UTI-UTC values, have been determined using data from only one observational system at a time, or by the combination of parameters previously obtained in such determinations. The question arises as to whether a simultaneous solution using data from several sources would provide an improved determination of such parameters. To pursue this reasoning, fifteen days of observations have been simulated using realistic networks of Lunar Laser Ranging (LLR), Satellite Laser Ranging (SLR) to Lageos, and Very Long Baseline Interferometry (VLBI) stations. A comparison has been done of the accuracy and precision of the ERP obtained from: (1) the individual system solutions, (2) the weighted means of those values, (3) all of the data by means of the combination of the normal equations obtained in 1, and (4) a grand solution with all the data. These simulations show that solutions done by the normal equation combination and grand solution methods provide the best or nearly the best ERP for all the periods considered, but that weighted mean solutions provide nearly the same accuracy and precision. VLBI solutions also provide similar accuracies.

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…

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.

Behavioral and ERP Evidence for Amodal Sluggish Attentional Shifting in Developmental Dyslexia

ERIC Educational Resources Information Center

Lallier, Marie; Tainturier, Marie-Josephe; Dering, Benjamin; Donnadieu, Sophie; Valdois, Sylviane; Thierry, Guillaume

2010-01-01

The goal of this study was to examine the claim that amodal deficits in attentional shifting may be the source of reading acquisition disorders in phonological developmental dyslexia (sluggish attentional shifting, SAS, theory, Hari & Renvall, 2001). We investigated automatic attentional shifting in the auditory and visual modalities in 13…

Quantifiers More or Less Quantify On-Line: ERP Evidence for Partial Incremental Interpretation

ERIC Educational Resources Information Center

Urbach, Thomas P.; Kutas, Marta

2010-01-01

Event-related brain potentials were recorded during RSVP reading to test the hypothesis that quantifier expressions are incrementally interpreted fully and immediately. In sentences tapping general knowledge ("Farmers grow crops/worms as their primary source of income"), Experiment 1 found larger N400s for atypical ("worms") than typical objects…

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.

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.

Analysis and visualization of single-trial event-related potentials

NASA Technical Reports Server (NTRS)

Jung, T. P.; Makeig, S.; Westerfield, M.; Townsend, J.; Courchesne, E.; Sejnowski, T. J.

2001-01-01

In this study, a linear decomposition technique, independent component analysis (ICA), is applied to single-trial multichannel EEG data from event-related potential (ERP) experiments. Spatial filters derived by ICA blindly separate the input data into a sum of temporally independent and spatially fixed components arising from distinct or overlapping brain or extra-brain sources. Both the data and their decomposition are displayed using a new visualization tool, the "ERP image," that can clearly characterize single-trial variations in the amplitudes and latencies of evoked responses, particularly when sorted by a relevant behavioral or physiological variable. These tools were used to analyze data from a visual selective attention experiment on 28 control subjects plus 22 neurological patients whose EEG records were heavily contaminated with blink and other eye-movement artifacts. Results show that ICA can separate artifactual, stimulus-locked, response-locked, and non-event-related background EEG activities into separate components, a taxonomy not obtained from conventional signal averaging approaches. This method allows: (1) removal of pervasive artifacts of all types from single-trial EEG records, (2) identification and segregation of stimulus- and response-locked EEG components, (3) examination of differences in single-trial responses, and (4) separation of temporally distinct but spatially overlapping EEG oscillatory activities with distinct relationships to task events. The proposed methods also allow the interaction between ERPs and the ongoing EEG to be investigated directly. We studied the between-subject component stability of ICA decomposition of single-trial EEG epochs by clustering components with similar scalp maps and activation power spectra. Components accounting for blinks, eye movements, temporal muscle activity, event-related potentials, and event-modulated alpha activities were largely replicated across subjects. Applying ICA and ERP image visualization to the analysis of sets of single trials from event-related EEG (or MEG) experiments can increase the information available from ERP (or ERF) data. Copyright 2001 Wiley-Liss, Inc.

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

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.

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.

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…

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

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.

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.

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.

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...

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.

Trait inferences in goal-directed behavior: ERP timing and localization under spontaneous and intentional processing

PubMed Central

Van den Eede, Sofie; Baetens, Kris; Vandekerckhove, Marie

2009-01-01

This study measured event-related potentials (ERPs) during multiple goal and trait inferences, under spontaneous or intentional instructions. Participants read sentences describing several goal-implying behaviors of a target person from which also a strong trait could be inferred or not. The last word of each sentence determined the consistency with the inference induced during preceding sentences. In comparison with behaviors that implied only a goal, stronger waveforms beginning at ∼150 ms were obtained when the behaviors additionally implied a trait. These ERPs showed considerable parallels between spontaneous and intentional inferences. This suggests that traits embedded in a stream of goal-directed behaviors were detected more rapidly and automatically than mere goals, irrespective of the participants’ spontaneous or intentional instructions. In line with this, source localization (LORETA) of the ERPs show predominantly activation in the temporo-parietal junction (TPJ) during 150–200 ms, suggesting that goals were detected at that time interval. During 200–300 ms, activation was stronger at the medial prefrontal cortex (mPFC) for multiple goals and traits as opposed to goals only, suggesting that traits were inferred during this time window. A cued recall measure taken after the presentation of the stimulus material support the occurrence of goal and trait inferences and shows significant correlations with the neural components, indicating that these components are valid neural indices of spontaneous and intentional social inferences. The early detection of multiple goal and trait inferences is explained in terms of their greater social relevance, leading to privileged attention allocation and processing in the brain. PMID:19270041

Investigating the Functional Utility of the Left Parietal ERP Old/New Effect: Brain Activity Predicts within But Not between Participant Variance in Episodic Recollection.

PubMed

MacLeod, Catherine A; Donaldson, David I

2017-01-01

A success story within neuroimaging has been the discovery of distinct neural correlates of episodic retrieval, providing insight into the processes that support memory for past life events. Here we focus on one commonly reported neural correlate, the left parietal old/new effect, a positive going modulation seen in event-related potential (ERP) data that is widely considered to index episodic recollection. Substantial evidence links changes in the size of the left parietal effect to changes in remembering, but the precise functional utility of the effect remains unclear. Here, using forced choice recognition of verbal stimuli, we present a novel population level test of the hypothesis that the magnitude of the left parietal effect correlates with memory performance. We recorded ERPs during old/new recognition, source accuracy and Remember/Know/Guess tasks in two large samples of healthy young adults, and successfully replicated existing within participant modulations of the magnitude of the left parietal effect with recollection. Critically, however, both datasets also show that across participants the magnitude of the left parietal effect does not correlate with behavioral measures of memory - including both subjective and objective estimates of recollection. We conclude that in these tasks, and across this healthy young adult population, the generators of the left parietal ERP effect do not index performance as expected. Taken together, these novel findings provide important constraints on the functional interpretation of the left parietal effect, suggesting that between group differences in the magnitude of old/new effects cannot always safely be used to infer differences in recollection.

The rapid distraction of attentional resources toward the source of incongruent stimulus input during multisensory conflict.

PubMed

Donohue, Sarah E; Todisco, Alexandra E; Woldorff, Marty G

2013-04-01

Neuroimaging work on multisensory conflict suggests that the relevant modality receives enhanced processing in the face of incongruency. However, the degree of stimulus processing in the irrelevant modality and the temporal cascade of the attentional modulations in either the relevant or irrelevant modalities are unknown. Here, we employed an audiovisual conflict paradigm with a sensory probe in the task-irrelevant modality (vision) to gauge the attentional allocation to that modality. ERPs were recorded as participants attended to and discriminated spoken auditory letters while ignoring simultaneous bilateral visual letter stimuli that were either fully congruent, fully incongruent, or partially incongruent (one side incongruent, one congruent) with the auditory stimulation. Half of the audiovisual letter stimuli were followed 500-700 msec later by a bilateral visual probe stimulus. As expected, ERPs to the audiovisual stimuli showed an incongruency ERP effect (fully incongruent versus fully congruent) of an enhanced, centrally distributed, negative-polarity wave starting ∼250 msec. More critically here, the sensory ERP components to the visual probes were larger when they followed fully incongruent versus fully congruent multisensory stimuli, with these enhancements greatest on fully incongruent trials with the slowest RTs. In addition, on the slowest-response partially incongruent trials, the P2 sensory component to the visual probes was larger contralateral to the preceding incongruent visual stimulus. These data suggest that, in response to conflicting multisensory stimulus input, the initial cognitive effect is a capture of attention by the incongruent irrelevant-modality input, pulling neural processing resources toward that modality, resulting in rapid enhancement, rather than rapid suppression, of that input.

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.

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.

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

Prediction of episodic acidification in North-eastern USA: An empirical/mechanistic approach

USGS Publications Warehouse

Davies, T.D.; Tranter, M.; Wigington, P.J.; Eshleman, K.N.; Peters, N.E.; Van Sickle, J.; DeWalle, David R.; Murdoch, Peter S.

1999-01-01

Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the North-eastern United States are used to develop an empirical/mechanistic scheme for prediction of the minimum values of acid neutralizing capacity (ANC) during episodes. An acidification episode is defined as a hydrological event during which ANC decreases. The pre-episode ANC is used to index the antecedent condition, and the stream flow increase reflects how much the relative contributions of sources of waters change during the episode. As much as 92% of the total variation in the minimum ANC in individual catchments can be explained (with levels of explanation >70% for nine of the 13 streams) by a multiple linear regression model that includes pre-episode ANC and change in discharge as independent variable. The predictive scheme is demonstrated to be regionally robust, with the regional variance explained ranging from 77 to 83%. The scheme is not successful for each ERP stream, and reasons are suggested for the individual failures. The potential for applying the predictive scheme to other watersheds is demonstrated by testing the model with data from the Panola Mountain Research Watershed in the South-eastern United States, where the variance explained by the model was 74%. The model can also be utilized to assess 'chemically new' and 'chemically old' water sources during acidification episodes.Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the Northeastern United States are used to develop an empirical/mechanistic scheme for prediction of the minimum values of acid neutralizing capacity (ANC) during episodes. An acidification episode is defined as a hydrological event during which ANC decreases. The pre-episode ANC is used to index the antecedent condition, and the stream flow increase reflects how much the relative contributions of sources of waters change during the episode. As much as 92% of the total variation in the minimum ANC in individual catchments can be explained (with levels of explanation >70% for nine of the 13 streams) by a multiple linear regression model that includes pre-episode ANC and change in discharge as independent variables. The predictive scheme is demonstrated to be regionally robust, with the regional variance explained ranging from 77 to 83%. The scheme is not successful for each ERP stream, and reasons are suggested for the individual failures. The potential for applying the predictive scheme to other watersheds is demonstrated by testing the model with data from the Panola Mountain Research Watershed in the South-eastern United States, where the variance explained by the model was 74%. The model can also be utilized to assess `chemically new' and `chemically old' water sources during acidification episodes.

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…

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...

Metabolomics variable selection and classification in the presence of observations below the detection limit using an extension of ERp.

PubMed

van Reenen, Mari; Westerhuis, Johan A; Reinecke, Carolus J; Venter, J Hendrik

2017-02-02

ERp is a variable selection and classification method for metabolomics data. ERp uses minimized classification error rates, based on data from a control and experimental group, to test the null hypothesis of no difference between the distributions of variables over the two groups. If the associated p-values are significant they indicate discriminatory variables (i.e. informative metabolites). The p-values are calculated assuming a common continuous strictly increasing cumulative distribution under the null hypothesis. This assumption is violated when zero-valued observations can occur with positive probability, a characteristic of GC-MS metabolomics data, disqualifying ERp in this context. This paper extends ERp to address two sources of zero-valued observations: (i) zeros reflecting the complete absence of a metabolite from a sample (true zeros); and (ii) zeros reflecting a measurement below the detection limit. This is achieved by allowing the null cumulative distribution function to take the form of a mixture between a jump at zero and a continuous strictly increasing function. The extended ERp approach is referred to as XERp. XERp is no longer non-parametric, but its null distributions depend only on one parameter, the true proportion of zeros. Under the null hypothesis this parameter can be estimated by the proportion of zeros in the available data. XERp is shown to perform well with regard to bias and power. To demonstrate the utility of XERp, it is applied to GC-MS data from a metabolomics study on tuberculosis meningitis in infants and children. We find that XERp is able to provide an informative shortlist of discriminatory variables, while attaining satisfactory classification accuracy for new subjects in a leave-one-out cross-validation context. XERp takes into account the distributional structure of data with a probability mass at zero without requiring any knowledge of the detection limit of the metabolomics platform. XERp is able to identify variables that discriminate between two groups by simultaneously extracting information from the difference in the proportion of zeros and shifts in the distributions of the non-zero observations. XERp uses simple rules to classify new subjects and a weight pair to adjust for unequal sample sizes or sensitivity and specificity requirements.

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

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.

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.

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.

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 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.

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.

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.

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.

A final report to the Laboratory Directed Research and Development committee on Project 93-ERP-075: ``X-ray laser propagation and coherence: Diagnosing fast-evolving, high-density laser plasmas using X-ray lasers``

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

Wan, A.S.; Cauble, R.; Da Silva, L.B.

1996-02-01

This report summarizes the major accomplishments of this three-year Laboratory Directed Research and Development (LDRD) Exploratory Research Project (ERP) entitled ``X-ray Laser Propagation and Coherence: Diagnosing Fast-evolving, High-density Laser Plasmas Using X-ray Lasers,`` tracking code 93-ERP-075. The most significant accomplishment of this project is the demonstration of a new laser plasma diagnostic: a soft x-ray Mach-Zehnder interferometer using a neonlike yttrium x-ray laser at 155 {angstrom} as the probe source. Detailed comparisons of absolute two-dimensional electron density profiles obtained from soft x-ray laser interferograms and profiles obtained from radiation hydrodynamics codes, such as LASNEX, will allow us to validate andmore » benchmark complex numerical models used to study the physics of laser-plasma interactions. Thus the development of soft x-ray interferometry technique provides a mechanism to probe the deficiencies of the numerical models and is an important tool for, the high-energy density physics and science-based stockpile stewardship programs. The authors have used the soft x-ray interferometer to study a number of high-density, fast evolving, laser-produced plasmas, such as the dynamics of exploding foils and colliding plasmas. They are pursuing the application of the soft x-ray interferometer to study ICF-relevant plasmas, such as capsules and hohlraums, on the Nova 10-beam facility. They have also studied the development of enhanced-coherence, shorter-pulse-duration, and high-brightness x-ray lasers. The utilization of improved x-ray laser sources can ultimately enable them to obtain three-dimensional holographic images of laser-produced plasmas.« less

Brain Imaging Research: The Detection of Deception Utilizing HD-ERP,

DTIC Science & Technology

2008-01-01

Queer, Put On, Mock, Put up a Front, Whopper, Bull, Bunk, Plant , Cant, and Simulate. Based on experts’ open-ended definitions (see Table 4), we came up...Plagiarize 1.55 (1.49) whitewash 3.66 (2.57) Disinformation 2.68 (2.15) Gloss 3.58 (2.43) Plant 2.80 (2.29) whopper 3.20 (2.66) Dissemble 3.79 (2.51) Go...order to deceive people false information deliberately and often covertly spread (as by the planting of rumors) in order to influence

Preparation breeds success: Brain activity predicts remembering.

PubMed

Herron, Jane E; Evans, Lisa H

2018-05-09

Successful retrieval of episodic information is thought to involve the adoption of memory states that ensure that stimulus events are treated as episodic memory cues (retrieval mode) and which can bias retrieval toward specific memory contents (retrieval orientation). The neural correlates of these memory states have been identified in many neuroimaging studies, yet critically there is no direct evidence that they facilitate retrieval success. We cued participants before each test item to prepare to complete an episodic (retrieve the encoding task performed on the item at study) or a non-episodic task. Our design allowed us to separate event-related potentials (ERPs) elicited by the preparatory episodic cue according to the accuracy of the subsequent memory judgment. We predicted that a correlate of retrieval orientation should be larger in magnitude preceding correct source judgments than that preceding source errors. This hypothesis was confirmed. Preparatory ERPs at bilateral frontal sites were significantly more positive-going when preceding correct source judgments than when preceding source errors or correct responses in a non-episodic baseline task. Furthermore this effect was not evident prior to recognized items associated with incorrect source judgments. This pattern of results indicates a direct contribution of retrieval orientation to the recovery of task-relevant information and highlights the value of separating preparatory neural activity at retrieval according to subsequent memory accuracy. Moreover, at a more general level this work demonstrates the important role of pre-stimulus processing in ecphory, which has remained largely neglected to date. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

The engagement of cortical areas preceding exogenous vergence eye movements.

PubMed

Wojtczak-Kwaśniewska, Monika; Przekoracka-Krawczyk, Anna; Van der Lubbe, Rob H J

2018-01-01

Source analyses on event related potentials (ERPs) derived from the electroencephalogram (EEG) were performed to examine the respective roles of cortical areas preceding exogenously triggered saccades, combined convergences, and combined divergences. All eye movements were triggered by the offset of a central fixation light emitting diode (LED) and the onset of a lateral LED at various depths in an otherwise fully darkened room. Our analyses revealed that three source pairs, two located in the frontal lobe-the frontal eye fields (FEF) and an anterior frontal area-, and one located within the occipital cortex, can account for 99.2% of the observed ERPs. Overall, the comparison between source activities revealed the largest activity in the occipital cortex, while no difference in activity between FEF and the anterior frontal area was obtained. For all sources, increased activity was observed for combined vergences, especially combined convergences, relative to saccades. Behavioral results revealed that onset latencies were longest for combined convergences, intermediate for combined divergences, and the shortest for saccades. Together, these findings fit within a perspective in which both occipital and frontal areas play an important role in retinal disparity detection. In the case of saccades and combined divergences stimulus-locked activity was larger than response-locked activity, while no difference between stimulus- and response-locked activity was observed for combined convergences. These findings seem to imply that the electrophysiological activity preceding exogenous eye movements consists of a sensory-related part that is under cortical control, while subcortical structures may be held responsible for final execution.

Integrative neuroscience: the role of a standardized database.

PubMed

Gordon, E; Cooper, N; Rennie, C; Hermens, D; Williams, L M

2005-04-01

Most brain related databases bring together specialized information, with a growing number that include neuroimaging measures. This article outlines the potential use and insights from the first entirely standardized and centralized database, which integrates information from neuroimaging measures (EEG, event related potential (ERP), structural/functional MRI), arousal (skin conductance responses (SCR)s, heart rate, respiration), neuropsychological and personality tests, genomics and demographics: The Brain Resource International Database. It comprises data from over 2000 "normative" subjects and a growing number of patients with neurological and psychiatric illnesses, acquired from over 50 laboratories (in the U.S.A, United Kingdom, Holland, South Africa, Israel and Australia), all with identical equipment and experimental procedures. Three primary goals of this database are to quantify individual differences in normative brain function, to compare an individual's performance to their database peers, and to provide a robust normative framework for clinical assessment and treatment prediction. We present three example demonstrations in relation to these goals. First, we show how consistent age differences may be quantified when large subject numbers are available, using EEG and ERP data from nearly 2000 stringently screened. normative subjects. Second, the use of a normalization technique provides a means to compare clinical subjects (50 ADHD subjects in this study) to the normative database with the effects of age and gender taken into account. Third, we show how a profile of EEG/ERP and autonomic measures potentially provides a means to predict treatment response in ADHD subjects. The example data consists of EEG under eyes open and eyes closed and ERP data for auditory oddball, working memory and Go-NoGo paradigms. Autonomic measures of skin conductance (tonic skin conductance level, SCL, and phasic skin conductance responses, SCRs) were acquired simultaneously with central EEG/ERP measures. The findings show that the power of large samples, tested using standardized protocols, allows for the quantification of individual differences that can subsequently be used to control such variation and to enhance the sensitivity and specificity of comparisons between normative and clinical groups. In terms of broader significance, the combination of size and multidimensional measures tapping the brain's core cognitive competencies, may provide a normative and evidence-based framework for individually-based assessments in "Personalized Medicine."

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.

Neural Correlates of Changes in a Visual Search Task due to Cognitive Training in Seniors

PubMed Central

Wild-Wall, Nele; Falkenstein, Michael; Gajewski, Patrick D.

2012-01-01

This study aimed to elucidate the underlying neural sources of near transfer after a multidomain cognitive training in older participants in a visual search task. Participants were randomly assigned to a social control, a no-contact control and a training group, receiving a 4-month paper-pencil and PC-based trainer guided cognitive intervention. All participants were tested in a before and after session with a conjunction visual search task. Performance and event-related potentials (ERPs) suggest that the cognitive training improved feature processing of the stimuli which was expressed in an increased rate of target detection compared to the control groups. This was paralleled by enhanced amplitudes of the frontal P2 in the ERP and by higher activation in lingual and parahippocampal brain areas which are discussed to support visual feature processing. Enhanced N1 and N2 potentials in the ERP for nontarget stimuli after cognitive training additionally suggest improved attention and subsequent processing of arrays which were not immediately recognized as targets. Possible test repetition effects were confined to processes of stimulus categorisation as suggested by the P3b potential. The results show neurocognitive plasticity in aging after a broad cognitive training and allow pinpointing the functional loci of effects induced by cognitive training. PMID:23029625

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.

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

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

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…

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…

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.

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.

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.

Contributions of Sensory Coding and Attentional Control to Individual Differences in Performance in Spatial Auditory Selective Attention Tasks.

PubMed

Dai, Lengshi; Shinn-Cunningham, Barbara G

2016-01-01

Listeners with normal hearing thresholds (NHTs) differ in their ability to steer attention to whatever sound source is important. This ability depends on top-down executive control, which modulates the sensory representation of sound in the cortex. Yet, this sensory representation also depends on the coding fidelity of the peripheral auditory system. Both of these factors may thus contribute to the individual differences in performance. We designed a selective auditory attention paradigm in which we could simultaneously measure envelope following responses (EFRs, reflecting peripheral coding), onset event-related potentials (ERPs) from the scalp (reflecting cortical responses to sound) and behavioral scores. We performed two experiments that varied stimulus conditions to alter the degree to which performance might be limited due to fine stimulus details vs. due to control of attentional focus. Consistent with past work, in both experiments we find that attention strongly modulates cortical ERPs. Importantly, in Experiment I, where coding fidelity limits the task, individual behavioral performance correlates with subcortical coding strength (derived by computing how the EFR is degraded for fully masked tones compared to partially masked tones); however, in this experiment, the effects of attention on cortical ERPs were unrelated to individual subject performance. In contrast, in Experiment II, where sensory cues for segregation are robust (and thus less of a limiting factor on task performance), inter-subject behavioral differences correlate with subcortical coding strength. In addition, after factoring out the influence of subcortical coding strength, behavioral differences are also correlated with the strength of attentional modulation of ERPs. These results support the hypothesis that behavioral abilities amongst listeners with NHTs can arise due to both subcortical coding differences and differences in attentional control, depending on stimulus characteristics and task demands.

Behavioral and brain pattern differences between acting and observing in an auditory task

PubMed Central

Karanasiou, Irene S; Papageorgiou, Charalabos; Tsianaka, Eleni I; Matsopoulos, George K; Ventouras, Errikos M; Uzunoglu, Nikolaos K

2009-01-01

Background Recent research has shown that errors seem to influence the patterns of brain activity. Additionally current notions support the idea that similar brain mechanisms are activated during acting and observing. The aim of the present study was to examine the patterns of brain activity of actors and observers elicited upon receiving feedback information of the actor's response. Methods The task used in the present research was an auditory identification task that included both acting and observing settings, ensuring concurrent ERP measurements of both participants. The performance of the participants was investigated in conditions of varying complexity. ERP data were analyzed with regards to the conditions of acting and observing in conjunction to correct and erroneous responses. Results The obtained results showed that the complexity induced by cue dissimilarity between trials was a demodulating factor leading to poorer performance. The electrophysiological results suggest that feedback information results in different intensities of the ERP patterns of observers and actors depending on whether the actor had made an error or not. The LORETA source localization method yielded significantly larger electrical activity in the supplementary motor area (Brodmann area 6), the posterior cingulate gyrus (Brodmann area 31/23) and the parietal lobe (Precuneus/Brodmann area 7/5). Conclusion These findings suggest that feedback information has a different effect on the intensities of the ERP patterns of actors and observers depending on whether the actor committed an error. Certain neural systems, including medial frontal area, posterior cingulate gyrus and precuneus may mediate these modulating effects. Further research is needed to elucidate in more detail the neuroanatomical and neuropsychological substrates of these systems. PMID:19154586

Parametric design and correlational analyses help integrating fMRI and electrophysiological data during face processing.

PubMed

Horovitz, Silvina G; Rossion, Bruno; Skudlarski, Pawel; Gore, John C

2004-08-01

Face perception is typically associated with activation in the inferior occipital, superior temporal (STG), and fusiform gyri (FG) and with an occipitotemporal electrophysiological component peaking around 170 ms on the scalp, the N170. However, the relationship between the N170 and the multiple face-sensitive activations observed in neuroimaging is unclear. It has been recently shown that the amplitude of the N170 component monotonically decreases as gaussian noise is added to a picture of a face [Jemel et al., 2003]. To help clarify the sources of the N170 without a priori assumptions regarding their number and locations, ERPs and fMRI were recorded in five subjects in the same experiment, in separate sessions. We used a parametric paradigm in which the amplitude of the N170 was modulated by varying the level of noise in a picture, and identified regions where the percent signal change in fMRI correlated with the ERP data. N170 signals were observed for pictures of both cars and faces but were stronger for faces. A monotonic decrease with added noise was observed for the N170 at right hemisphere sites but was less clear on the left and occipital central sites. Correlations between fMRI signal and N170 amplitudes for faces were highly significant (P < 0.001) in bilateral fusiform gyrus and superior temporal gyrus. For cars, the strongest correlations were observed in the parahippocampal region and in the STG (P < 0.005). Besides contributing to clarify the spatiotemporal course of face processing, this study illustrates how ERP information may be used synergistically in fMRI analyses. Parametric designs may be developed further to provide some timing information on fMRI activity and help identify the generators of ERP signals.

Neural Correlates of User-initiated Motor Success and Failure - A Brain-Computer Interface Perspective.

PubMed

Yazmir, Boris; Reiner, Miriam

2018-05-15

Any motor action is, by nature, potentially accompanied by human errors. In order to facilitate development of error-tailored Brain-Computer Interface (BCI) correction systems, we focused on internal, human-initiated errors, and investigated EEG correlates of user outcome successes and errors during a continuous 3D virtual tennis game against a computer player. We used a multisensory, 3D, highly immersive environment. Missing and repelling the tennis ball were considered, as 'error' (miss) and 'success' (repel). Unlike most previous studies, where the environment "encouraged" the participant to perform a mistake, here errors happened naturally, resulting from motor-perceptual-cognitive processes of incorrect estimation of the ball kinematics, and can be regarded as user internal, self-initiated errors. Results show distinct and well-defined Event-Related Potentials (ERPs), embedded in the ongoing EEG, that differ across conditions by waveforms, scalp signal distribution maps, source estimation results (sLORETA) and time-frequency patterns, establishing a series of typical features that allow valid discrimination between user internal outcome success and error. The significant delay in latency between positive peaks of error- and success-related ERPs, suggests a cross-talk between top-down and bottom-up processing, represented by an outcome recognition process, in the context of the game world. Success-related ERPs had a central scalp distribution, while error-related ERPs were centro-parietal. The unique characteristics and sharp differences between EEG correlates of error/success provide the crucial components for an improved BCI system. The features of the EEG waveform can be used to detect user action outcome, to be fed into the BCI correction system. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Response competition and response inhibition during different choice-discrimination tasks: evidence from ERP measured inside MRI scanner.

PubMed

Gonzalez-Rosa, Javier J; Inuggi, Alberto; Blasi, Valeria; Cursi, Marco; Annovazzi, Pietro; Comi, Giancarlo; Falini, Andrea; Leocani, Letizia

2013-07-01

We investigated the neural correlates underlying response inhibition and conflict detection processes using ERPs and source localization analyses simultaneously acquired during fMRI scanning. ERPs were elicited by a simple reaction time task (SRT), a Go/NoGo task, and a Stroop-like task (CST). The cognitive conflict was thus manipulated in order to probe the degree to which information processing is shared across cognitive systems. We proposed to dissociate inhibition and interference conflict effects on brain activity by using identical Stroop-like congruent/incongruent stimuli in all three task contexts and while varying the response required. NoGo-incongruent trials showed a larger N2 and enhanced activations of rostral anterior cingulate cortex (ACC) and pre-supplementary motor area, whereas Go-congruent trials showed a larger P3 and increased parietal activations. Congruent and incongruent conditions of the CST task also elicited similar N2, P3 and late negativity (LN) ERPs, though CST-incongruent trials revealed a larger LN and enhanced prefrontal and ACC activations. Considering the stimulus probability and experimental manipulation of our study, current findings suggest that NoGo N2 and frontal NoGo P3 appear to be more associated to response inhibition rather than a specific conflict monitoring, whereas occipito-parietal P3 of Go and CST conditions may be more linked to a planned response competition between the prepared and required response. LN, however, appears to be related to higher level conflict monitoring associated with response choice-discrimination but not when the presence of cognitive conflict is associated with response inhibition. Copyright © 2013. Published by Elsevier B.V.

Investigating the Functional Utility of the Left Parietal ERP Old/New Effect: Brain Activity Predicts within But Not between Participant Variance in Episodic Recollection

PubMed Central

MacLeod, Catherine A.; Donaldson, David I.

2017-01-01

A success story within neuroimaging has been the discovery of distinct neural correlates of episodic retrieval, providing insight into the processes that support memory for past life events. Here we focus on one commonly reported neural correlate, the left parietal old/new effect, a positive going modulation seen in event-related potential (ERP) data that is widely considered to index episodic recollection. Substantial evidence links changes in the size of the left parietal effect to changes in remembering, but the precise functional utility of the effect remains unclear. Here, using forced choice recognition of verbal stimuli, we present a novel population level test of the hypothesis that the magnitude of the left parietal effect correlates with memory performance. We recorded ERPs during old/new recognition, source accuracy and Remember/Know/Guess tasks in two large samples of healthy young adults, and successfully replicated existing within participant modulations of the magnitude of the left parietal effect with recollection. Critically, however, both datasets also show that across participants the magnitude of the left parietal effect does not correlate with behavioral measures of memory – including both subjective and objective estimates of recollection. We conclude that in these tasks, and across this healthy young adult population, the generators of the left parietal ERP effect do not index performance as expected. Taken together, these novel findings provide important constraints on the functional interpretation of the left parietal effect, suggesting that between group differences in the magnitude of old/new effects cannot always safely be used to infer differences in recollection. PMID:29259551

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...

ERP Index of the Morphological Family Size Effect during Word Recognition

ERIC Educational Resources Information Center

Kwon, Youan; Nam, Kichun; Lee, Yoonhyoung

2012-01-01

The purpose of this study was to examine whether the N400 is affected by the semantic richness of associated neighboring word members or by the density of the orthographic syllable neighborhood. Another purpose of this study was to investigate the source of the different LPC in respect to the semantic richness. To do so, the density of the…

Age-Related Occipito-Temporal Hypoactivation during Visual Search: Relationships between mN2pc Sources and Performance

ERIC Educational Resources Information Center

Lorenzo-Lopez, L.; Gutierrez, R.; Moratti, S.; Maestu, F.; Cadaveira, F.; Amenedo, E.

2011-01-01

Recently, an event-related potential (ERP) study (Lorenzo-Lopez et al., 2008) provided evidence that normal aging significantly delays and attenuates the electrophysiological correlate of the allocation of visuospatial attention (N2pc component) during a feature-detection visual search task. To further explore the effects of normal aging on the…

Emotion processing in the visual brain: a MEG analysis.

PubMed

Peyk, Peter; Schupp, Harald T; Elbert, Thomas; Junghöfer, Markus

2008-06-01

Recent functional magnetic resonance imaging (fMRI) and event-related brain potential (ERP) studies provide empirical support for the notion that emotional cues guide selective attention. Extending this line of research, whole head magneto-encephalogram (MEG) was measured while participants viewed in separate experimental blocks a continuous stream of either pleasant and neutral or unpleasant and neutral pictures, presented for 330 ms each. Event-related magnetic fields (ERF) were analyzed after intersubject sensor coregistration, complemented by minimum norm estimates (MNE) to explore neural generator sources. Both streams of analysis converge by demonstrating the selective emotion processing in an early (120-170 ms) and a late time interval (220-310 ms). ERF analysis revealed that the polarity of the emotion difference fields was reversed across early and late intervals suggesting distinct patterns of activation in the visual processing stream. Source analysis revealed the amplified processing of emotional pictures in visual processing areas with more pronounced occipito-parieto-temporal activation in the early time interval, and a stronger engagement of more anterior, temporal, regions in the later interval. Confirming previous ERP studies showing facilitated emotion processing, the present data suggest that MEG provides a complementary look at the spread of activation in the visual processing stream.

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.

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.

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

A comparison of auditory evoked potentials to acoustic beats and to binaural beats.

PubMed

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

2010-04-01

The purpose of this study was to compare cortical brain responses evoked by amplitude modulated acoustic beats of 3 and 6 Hz in tones of 250 and 1000 Hz with those evoked by their binaural beats counterparts in unmodulated tones to indicate whether the cortical processes involved differ. Event-related potentials (ERPs) were recorded to 3- and 6-Hz acoustic and binaural beats in 2000 ms duration 250 and 1000 Hz tones presented with approximately 1 s intervals. Latency, amplitude and source current density estimates of ERP components to beats-evoked oscillations were determined and compared across beat types, beat frequencies and base (carrier) frequencies. All stimuli evoked tone-onset components followed by oscillations corresponding to the beat frequency, and a subsequent tone-offset complex. Beats-evoked oscillations were higher in amplitude in response to acoustic than to binaural beats, to 250 than to 1000 Hz base frequency and to 3 Hz than to 6 Hz beat frequency. Sources of the beats-evoked oscillations across all stimulus conditions located mostly to left temporal lobe areas. Differences between estimated sources of potentials to acoustic and binaural beats were not significant. The perceptions of binaural beats involve cortical activity that is not different than acoustic beats in distribution and in the effects of beat- and base frequency, indicating similar cortical processing. Copyright 2010 Elsevier B.V. All rights reserved.

Event-related potential evidence suggesting voters remember political events that never happened

PubMed Central

Federmeier, Kara D.; Gonsalves, Brian D.

2014-01-01

Voters tend to misattribute issue positions to political candidates that are consistent with their partisan affiliation, even though these candidates have never explicitly stated or endorsed such stances. The prevailing explanation in political science is that voters misattribute candidates’ issue positions because they use their political knowledge to make educated but incorrect guesses. We suggest that voter errors can also stem from a different source: false memories. The current study examined event-related potential (ERP) responses to misattributed and accurately remembered candidate issue information. We report here that ERP responses to misattributed information can elicit memory signals similar to that of correctly remembered old information—a pattern consistent with a false memory rather than educated guessing interpretation of these misattributions. These results suggest that some types of voter misinformation about candidates may be harder to correct than previously thought. PMID:23202775

The Stroop matching task presents conflict at both the response and nonresponse levels: an event-related potential and electromyography study.

PubMed

Caldas, A L; Machado-Pinheiro, W; Souza, L B; Motta-Ribeiro, G C; David, I A

2012-09-01

In the Stroop matching task, a Stroop word is compared to a colored bar. The origin of the conflict presented by this task is a topic of current debate. In an effort to disentangle nonresponse and response conflicts, we recorded electromyography (EMG) and event-related potentials (ERPs) while participants performed the task. The N450 component was sensitive to the relationship of color surfaces, regardless of the response, suggesting the participation of nonresponse conflict. Incompatible arrays (e.g., incongruent Stroop stimuli during "same" responses) presented a substantial amount of double EMG activation and slower EMG latencies, suggesting the participation of response conflict. We propose that both response and nonresponse conflicts are sources of these effects. The combined use of the EMG and ERP techniques played an important role in elucidating the conflicts immersed in the Stroop matching task. Copyright © 2012 Society for Psychophysiological Research.

Font size matters--emotion and attention in cortical responses to written words.

PubMed

Bayer, Mareike; Sommer, Werner; Schacht, Annekathrin

2012-01-01

For emotional pictures with fear-, disgust-, or sex-related contents, stimulus size has been shown to increase emotion effects in attention-related event-related potentials (ERPs), presumably reflecting the enhanced biological impact of larger emotion-inducing pictures. If this is true, size should not enhance emotion effects for written words with symbolic and acquired meaning. Here, we investigated ERP effects of font size for emotional and neutral words. While P1 and N1 amplitudes were not affected by emotion, the early posterior negativity started earlier and lasted longer for large relative to small words. These results suggest that emotion-driven facilitation of attention is not necessarily based on biological relevance, but might generalize to stimuli with arbitrary perceptual features. This finding points to the high relevance of written language in today's society as an important source of emotional meaning.

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...

ERP signs of categorical and supra-categorical processing of visual information.

PubMed

Zani, Alberto; Marsili, Giulia; Senerchia, Annapaola; Orlandi, Andrea; Citron, Francesca M M; Rizzi, Ezia; Proverbio, Alice M

2015-01-01

The aim of the present study was to investigate to what extent shared and distinct brain mechanisms are possibly subserving the processing of visual supra-categorical and categorical knowledge as observed with event-related potentials of the brain. Access time to these knowledge types was also investigated. Picture pairs of animals, objects, and mixed types were presented. Participants were asked to decide whether each pair contained pictures belonging to the same category (either animals or man-made objects) or to different categories by pressing one of two buttons. Response accuracy and reaction times (RTs) were also recorded. Both ERPs and RTs were grand-averaged separately for the same-different supra-categories and the animal-object categories. Behavioral performance was faster for more endomorphic pairs, i.e., animals vs. objects and same vs. different category pairs. For ERPs, a modulation of the earliest C1 and subsequent P1 responses to the same vs. different supra-category pairs, but not to the animal vs. object category pairs, was found. This finding supports the view that early afferent processing in the striate cortex can be boosted as a by-product of attention allocated to the processing of shapes and basic features that are mismatched, but not to their semantic quintessence, during same-different supra-categorical judgment. Most importantly, the fact that this processing accrual occurred independent of a traditional experimental condition requiring selective attention to a stimulus source out of the various sources addressed makes it conceivable that this processing accrual may arise from the attentional demand deriving from the alternate focusing of visual attention within and across stimulus categorical pairs' basic structural features. Additional posterior ERP reflections of the brain more prominently processing animal category and same-category pairs were observed at the N1 and N2 levels, respectively, as well as at a late positive complex level, overall most likely related to different stages of analysis of the greater endomorphy of these shape groups. Conversely, an enhanced fronto-central and fronto-lateral N2 as well as a centro-parietal N400 to man-made objects and different-category pairs were found, possibly indexing processing of these entities' lower endomorphy and isomorphy at the basic features and semantic levels, respectively. Overall, the present ERP results revealed shared and distinct mechanisms of access to supra-categorical and categorical knowledge in the same way in which shared and distinct neural representations underlie the processing of diverse semantic categories. Additionally, they outlined the serial nature of categorical and supra-categorical representations, indicating the sequential steps of access to these separate knowledge types. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

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.

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.

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.

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.

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

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.

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.

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

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

Driving with Intuition: A Preregistered Study about the EEG Anticipation of Simulated Random Car Accidents

PubMed Central

Duma, Gian Marco; Mento, Giovanni; Manari, Tommaso; Martinelli, Massimiliano

2017-01-01

The study of neural pre-stimulus or “anticipatory” activity opened a new window for understanding how the brain actively constructs the forthcoming reality. Usually, experimental paradigms designed to study anticipatory activity make use of stimuli. The purpose of the present study is to expand the study of neural anticipatory activity upon the temporal occurrence of dichotomic, statistically unpredictable (random) stimuli within an ecological experimental paradigm. To this purpose, we used a simplified driving simulation including two possible, randomly-presented trial types: a car crash end trial and a no car crash end trial. Event Related Potentials (ERP) were extracted -3,000 ms before stimulus onset. We identified a fronto-central negativity starting around 1,000 ms before car crash presentation. By contrast, a whole-scalp distributed positivity characterized the anticipatory activity observed before the end of the trial in the no car crash end condition. The present data are in line with the hypothesis that the brain may also anticipate dichotomic, statistically unpredictable stimuli, relaying onto different pre-stimulus ERP activity. Possible integration with car-smart-systems is also suggested. PMID:28103303

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.

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

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.

Open- and Closed-Skill Exercise Interventions Produce Different Neurocognitive Effects on Executive Functions in the Elderly: A 6-Month Randomized, Controlled Trial

PubMed Central

Tsai, Chia-Liang; Pan, Chien-Yu; Chen, Fu-Chen; Tseng, Yu-Ting

2017-01-01

This study aimed to explore the effects of open- and closed-skill exercise interventions on the neurocognitive performance of executive functions in the elderly. Sixty-four healthy elderly males were randomly assigned to either a closed-skill (bike riding or brisk walking/jogging, n = 22), open-skill (table tennis, n = 21), or control (n = 21) group. Various neuropsychological [e.g., accuracy rates (AR) and reaction time (RT)] and electrophysiological [e.g., event-related potential (ERP) P3 component] measures were assessed during a variant of the task-switching paradigm, as well as an N-back task at baseline and after either a 6-month exercise intervention or control period. The results showed that, when performing the task-switching paradigm, the two exercise groups relative to control group showed significantly faster RTs in the switch trials after the exercise intervention. However, the RT facilitation in the non-switch and switch trials post-exercise relative to pre-exercise only emerged in the open-skill group. In terms of the N-back task, the two exercise groups significantly increased ARs in the 1-back condition after the exercise intervention, and the beneficial AR effect on the 2-back condition only emerged in the closed-skill group. In addition, the two exercise groups exhibited significantly larger P3 amplitudes on the frontal-to-parietal cortex areas after the exercise intervention relative to the baseline when performing the two cognitive tasks. These neurocognitive results still remained unchanged even when the confounding factors (e.g., cardiorespiratory fitness, social participation, and BMI) were controlled for. The present study concluded that, although 6-month open- and closed-skill exercise interventions facilitate overall electrophysiological effects (i.e., increased ERP P3 amplitudes) on the frontal-to-parietal cortices in the elderly, the two exercise modes produced different levels of neuropsychologically beneficial effects on RTs of the task-switching paradigm (i.e., lessened RTs) and ARs of the N-back task (i.e., enhanced ARs). The distinctive neurocognitive changes induced by open- and closed-skill exercise have implications for task switching and working memory in elderly individuals, especially with such cognitive functioning impairments. PMID:28959200

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.

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.

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.

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.

Two Sides of the Same Coin: ERP and Wavelet Analyses of Visual Potentials Evoked and Induced by Task-Relevant Faces.

PubMed

Van der Lubbe, Rob H J; Szumska, Izabela; Fajkowska, Małgorzata

2016-01-01

New analysis techniques of the electroencephalogram (EEG) such as wavelet analysis open the possibility to address questions that may largely improve our understanding of the EEG and clarify its relation with related potentials (ER Ps). Three issues were addressed. 1) To what extent can early ERERP components be described as transient evoked oscillations in specific frequency bands? 2) Total EEG power (TP) after a stimulus consists of pre-stimulus baseline power (BP), evoked power (EP), and induced power (IP), but what are their respective contributions? 3) The Phase Reset model proposes that BP predicts EP, while the evoked model holds that BP is unrelated to EP; which model is the most valid one? EEG results on NoGo trials for 123 individuals that took part in an experiment with emotional facial expressions were examined by computing ERPs and by performing wavelet analyses on the raw EEG and on ER Ps. After performing several multiple regression analyses, we obtained the following answers. First, the P1, N1, and P2 components can by and large be described as transient oscillations in the α and θ bands. Secondly, it appears possible to estimate the separate contributions of EP, BP, and IP to TP, and importantly, the contribution of IP is mostly larger than that of EP. Finally, no strong support was obtained for either the Phase Reset or the Evoked model. Recent models are discussed that may better explain the relation between raw EEG and ERPs.

Two Sides of the Same Coin: ERP and Wavelet Analyses of Visual Potentials Evoked and Induced by Task-Relevant Faces

PubMed Central

Van der Lubbe, Rob H. J.; Szumska, Izabela; Fajkowska, Małgorzata

2016-01-01

New analysis techniques of the electroencephalogram (EEG) such as wavelet analysis open the possibility to address questions that may largely improve our understanding of the EEG and clarify its relation with related potentials (ER Ps). Three issues were addressed. 1) To what extent can early ERERP components be described as transient evoked oscillations in specific frequency bands? 2) Total EEG power (TP) after a stimulus consists of pre-stimulus baseline power (BP), evoked power (EP), and induced power (IP), but what are their respective contributions? 3) The Phase Reset model proposes that BP predicts EP, while the evoked model holds that BP is unrelated to EP; which model is the most valid one? EEG results on NoGo trials for 123 individuals that took part in an experiment with emotional facial expressions were examined by computing ERPs and by performing wavelet analyses on the raw EEG and on ER Ps. After performing several multiple regression analyses, we obtained the following answers. First, the P1, N1, and P2 components can by and large be described as transient oscillations in the α and θ bands. Secondly, it appears possible to estimate the separate contributions of EP, BP, and IP to TP, and importantly, the contribution of IP is mostly larger than that of EP. Finally, no strong support was obtained for either the Phase Reset or the Evoked model. Recent models are discussed that may better explain the relation between raw EEG and ERPs. PMID:28154612

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.

Seeing voices: High-density electrical mapping and source-analysis of the multisensory mismatch negativity evoked during the McGurk illusion.

PubMed

Saint-Amour, Dave; De Sanctis, Pierfilippo; Molholm, Sophie; Ritter, Walter; Foxe, John J

2007-02-01

Seeing a speaker's facial articulatory gestures powerfully affects speech perception, helping us overcome noisy acoustical environments. One particularly dramatic illustration of visual influences on speech perception is the "McGurk illusion", where dubbing an auditory phoneme onto video of an incongruent articulatory movement can often lead to illusory auditory percepts. This illusion is so strong that even in the absence of any real change in auditory stimulation, it activates the automatic auditory change-detection system, as indexed by the mismatch negativity (MMN) component of the auditory event-related potential (ERP). We investigated the putative left hemispheric dominance of McGurk-MMN using high-density ERPs in an oddball paradigm. Topographic mapping of the initial McGurk-MMN response showed a highly lateralized left hemisphere distribution, beginning at 175 ms. Subsequently, scalp activity was also observed over bilateral fronto-central scalp with a maximal amplitude at approximately 290 ms, suggesting later recruitment of right temporal cortices. Strong left hemisphere dominance was again observed during the last phase of the McGurk-MMN waveform (350-400 ms). Source analysis indicated bilateral sources in the temporal lobe just posterior to primary auditory cortex. While a single source in the right superior temporal gyrus (STG) accounted for the right hemisphere activity, two separate sources were required, one in the left transverse gyrus and the other in STG, to account for left hemisphere activity. These findings support the notion that visually driven multisensory illusory phonetic percepts produce an auditory-MMN cortical response and that left hemisphere temporal cortex plays a crucial role in this process.

Seeing voices: High-density electrical mapping and source-analysis of the multisensory mismatch negativity evoked during the McGurk illusion

PubMed Central

Saint-Amour, Dave; De Sanctis, Pierfilippo; Molholm, Sophie; Ritter, Walter; Foxe, John J.

2006-01-01

Seeing a speaker’s facial articulatory gestures powerfully affects speech perception, helping us overcome noisy acoustical environments. One particularly dramatic illustration of visual influences on speech perception is the “McGurk illusion”, where dubbing an auditory phoneme onto video of an incongruent articulatory movement can often lead to illusory auditory percepts. This illusion is so strong that even in the absence of any real change in auditory stimulation, it activates the automatic auditory change-detection system, as indexed by the mismatch negativity (MMN) component of the auditory event-related potential (ERP). We investigated the putative left hemispheric dominance of McGurk-MMN using high-density ERPs in an oddball paradigm. Topographic mapping of the initial McGurk-MMN response showed a highly lateralized left hemisphere distribution, beginning at 175 ms. Subsequently, scalp activity was also observed over bilateral fronto-central scalp with a maximal amplitude at ~290 ms, suggesting later recruitment of right temporal cortices. Strong left hemisphere dominance was again observed during the last phase of the McGurk-MMN waveform (350–400 ms). Source analysis indicated bilateral sources in the temporal lobe just posterior to primary auditory cortex. While a single source in the right superior temporal gyrus (STG) accounted for the right hemisphere activity, two separate sources were required, one in the left transverse gyrus and the other in STG, to account for left hemisphere activity. These findings support the notion that visually driven multisensory illusory phonetic percepts produce an auditory-MMN cortical response and that left hemisphere temporal cortex plays a crucial role in this process. PMID:16757004

Test Area C-64 Range Environmental Assessment, Revision 1

DTIC Science & Technology

2010-10-01

DOI U.S. Department of the Interior DNL Day–Night Average Sound Level DU Depleted Uranium EBD Environmental Baseline Document EIAP Environmental...vulnerability, burning sensitivity, drop tests, bullet impact tests, sympathetic detonation tests, advanced warhead design tests, and depleted uranium (DU...land back to range use. Source: U.S. Air Force, 2009 DU = depleted uranium ; ERP = Environmental Restoration Program; LUC = land use control; RW

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.

The cortical generators of P3a and P3b: a LORETA study.

PubMed

Volpe, U; Mucci, A; Bucci, P; Merlotti, E; Galderisi, S; Maj, M

2007-07-12

The P3 is probably the most well known component of the brain event-related potentials (ERPs). Using a three-tone oddball paradigm two different components can be identified: the P3b elicited by rare target stimuli and the P3a elicited by the presentation of rare non-target stimuli. Although the two components may partially overlap in time and space, they have a different scalp topography suggesting different neural generators. The present study is aimed at defining the scalp topography of the two P3 components by means of reference-independent methods and identifying their electrical cortical generators by using the low-resolution electromagnetic tomography (LORETA). ERPs were recorded during a three-tone oddball task in 32 healthy, right-handed university students. The scalp topography of the P3 components was assessed by means of the brain electrical microstates technique and their cortical sources were evaluated by LORETA. P3a and P3b showed different scalp topography and cortical sources. The P3a electrical field had a more anterior distribution as compared to the P3b and its generators were localized in cingulate, frontal and right parietal areas. P3b sources included bilateral frontal, parietal, limbic, cingulate and temporo-occipital regions. Differences in scalp topography and cortical sources suggest that the two components reflect different neural processes. Our findings on cortical generators are in line with the hypothesis that P3a reflects the automatic allocation of attention, while P3b is related to the effortful processing of task-relevant events.

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.

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.

Grand average ERP-image plotting and statistics: A method for comparing variability in event-related single-trial EEG activities across subjects and conditions

PubMed Central

Delorme, Arnaud; Miyakoshi, Makoto; Jung, Tzyy-Ping; Makeig, Scott

2014-01-01

With the advent of modern computing methods, modeling trial-to-trial variability in biophysical recordings including electroencephalography (EEG) has become of increasingly interest. Yet no widely used method exists for comparing variability in ordered collections of single-trial data epochs across conditions and subjects. We have developed a method based on an ERP-image visualization tool in which potential, spectral power, or some other measure at each time point in a set of event-related single-trial data epochs are represented as color coded horizontal lines that are then stacked to form a 2-D colored image. Moving-window smoothing across trial epochs can make otherwise hidden event-related features in the data more perceptible. Stacking trials in different orders, for example ordered by subject reaction time, by context-related information such as inter-stimulus interval, or some other characteristic of the data (e.g., latency-window mean power or phase of some EEG source) can reveal aspects of the multifold complexities of trial-to-trial EEG data variability. This study demonstrates new methods for computing and visualizing grand ERP-image plots across subjects and for performing robust statistical testing on the resulting images. These methods have been implemented and made freely available in the EEGLAB signal-processing environment that we maintain and distribute. PMID:25447029

Neurodynamics of executive control processes in bilinguals: evidence from ERP and source reconstruction analyses.

PubMed

Heidlmayr, Karin; Hemforth, Barbara; Moutier, Sylvain; Isel, Frédéric

2015-01-01

The present study was designed to examine the impact of bilingualism on the neuronal activity in different executive control processes namely conflict monitoring, control implementation (i.e., interference suppression and conflict resolution) and overcoming of inhibition. Twenty-two highly proficient but non-balanced successive French-German bilingual adults and 22 monolingual adults performed a combined Stroop/Negative priming task while event-related potential (ERP) were recorded online. The data revealed that the ERP effects were reduced in bilinguals in comparison to monolinguals but only in the Stroop task and limited to the N400 and the sustained fronto-central negative-going potential time windows. This result suggests that bilingualism may impact the process of control implementation rather than the process of conflict monitoring (N200). Critically, our study revealed a differential time course of the involvement of the anterior cingulate cortex (ACC) and the prefrontal cortex (PFC) in conflict processing. While the ACC showed major activation in the early time windows (N200 and N400) but not in the latest time window (late sustained negative-going potential), the PFC became unilaterally active in the left hemisphere in the N400 and the late sustained negative-going potential time windows. Taken together, the present electroencephalography data lend support to a cascading neurophysiological model of executive control processes, in which ACC and PFC may play a determining role.

Neurodynamics of executive control processes in bilinguals: evidence from ERP and source reconstruction analyses

PubMed Central

Heidlmayr, Karin; Hemforth, Barbara; Moutier, Sylvain; Isel, Frédéric

2015-01-01

The present study was designed to examine the impact of bilingualism on the neuronal activity in different executive control processes namely conflict monitoring, control implementation (i.e., interference suppression and conflict resolution) and overcoming of inhibition. Twenty-two highly proficient but non-balanced successive French–German bilingual adults and 22 monolingual adults performed a combined Stroop/Negative priming task while event-related potential (ERP) were recorded online. The data revealed that the ERP effects were reduced in bilinguals in comparison to monolinguals but only in the Stroop task and limited to the N400 and the sustained fronto-central negative-going potential time windows. This result suggests that bilingualism may impact the process of control implementation rather than the process of conflict monitoring (N200). Critically, our study revealed a differential time course of the involvement of the anterior cingulate cortex (ACC) and the prefrontal cortex (PFC) in conflict processing. While the ACC showed major activation in the early time windows (N200 and N400) but not in the latest time window (late sustained negative-going potential), the PFC became unilaterally active in the left hemisphere in the N400 and the late sustained negative-going potential time windows. Taken together, the present electroencephalography data lend support to a cascading neurophysiological model of executive control processes, in which ACC and PFC may play a determining role. PMID:26124740

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.

Transforming the Force: A Comparative Analysis of the Department of Defense’s (DOD’s) Enterprise Resource Planning (ERP) Systems

DTIC Science & Technology

2007-09-01

the smaller ERP companies that produce specialized ERPs for particular industries. Five former IBM employees founded SAP and created the first ERP...Computer Sciences Corporations (CSC), Price Waterhouse Coopers, EDS, and IBM [2]. Selecting the right integrators is critical because they are the link... IBM was chosen as the integrator for the NEMAIS pilot. 5. Pilot Results and Road Ahead Between late 1998 and early 2002, the four Navy pilots took

Enhanced recovery pathways optimize health outcomes and resource utilization: a meta-analysis of randomized controlled trials in colorectal surgery.

PubMed

Adamina, Michel; Kehlet, Henrik; Tomlinson, George A; Senagore, Anthony J; Delaney, Conor P

2011-06-01

Health care systems provide care to increasingly complex and elderly patients. Colorectal surgery is a prime example, with high volumes of major procedures, significant morbidity, prolonged hospital stays, and unplanned readmissions. This situation is exacerbated by an exponential rise in costs that threatens the stability of health care systems. Enhanced recovery pathways (ERP) have been proposed as a means to reduce morbidity and improve effectiveness of care. We have reviewed the evidence supporting the implementation of ERP in clinical practice. Medline, Embase, and the Cochrane library were searched for randomized, controlled trials comparing ERP with traditional care in colorectal surgery. Systematic reviews and papers on ERP based on data published in major surgical and anesthesiology journals were critically reviewed by international contributors, experienced in the development and implementation of ERP. A random-effect Bayesian meta-analysis was performed, including 6 randomized, controlled trials totalizing 452 patients. For patients adhering to ERP, length of stay decreased by 2.5 days (95% credible interval [CrI] -3.92 to -1.11), whereas 30-day morbidity was halved (relative risk, 0.52; 95% CrI, 0.36-0.73) and readmission was not increased (relative risk, 0.59; 95% CrI, 0.14-1.43) when compared with patients undergoing traditional care. Adherence to ERP achieves a reproducible improvement in the quality of care by enabling standardization of health care processes. Thus, while accelerating recovery and safely reducing hospital stay, ERPs optimize utilization of health care resources. ERPs can and should be routinely used in care after colorectal and other major gastrointestinal procedures. Copyright © 2011 Mosby, Inc. All rights reserved.

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.

ERp29 Regulates ΔF508 and Wild-type Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Trafficking to the Plasma Membrane in Cystic Fibrosis (CF) and Non-CF Epithelial Cells*

PubMed Central

Suaud, Laurence; Miller, Katelyn; Alvey, Lora; Yan, Wusheng; Robay, Amal; Kebler, Catherine; Kreindler, James L.; Guttentag, Susan; Hubbard, Michael J.; Rubenstein, Ronald C.

2011-01-01

Sodium 4-phenylbutyrate (4PBA) improves the intracellular trafficking of ΔF508-CFTR in cystic fibrosis (CF) epithelial cells. The underlying mechanism is uncertain, but 4PBA modulates the expression of some cytosolic molecular chaperones. To identify other 4PBA-regulated proteins that might regulate ΔF508-CFTR trafficking, we performed a differential display RT-PCR screen on IB3-1 CF bronchiolar epithelial cells exposed to 4PBA. One transcript up-regulated by 4PBA encoded ERp29, a luminal resident of the endoplasmic reticulum (ER) thought to be a novel molecular chaperone. We tested the hypothesis that ERp29 is a 4PBA-regulated ER chaperone that influences ΔF508-CFTR trafficking. ERp29 mRNA and protein expression was significantly increased (∼1.5-fold) in 4PBA-treated IB3-1 cells. In Xenopus oocytes, ERp29 overexpression increased the functional expression of both wild-type and ΔF508-CFTR over 3-fold and increased wild-type cystic fibrosis transmembrane conductance regulator (CFTR) plasma membrane expression. In CFBE41o− WT-CFTR cells, expression of and short circuit currents mediated by CFTR decreased upon depletion of ERp29 as did maturation of newly synthesized CFTR. In IB3-1 cells, ΔF508-CFTR co-immunoprecipitated with endogenous ERp29, and overexpression of ERp29 led to increased ΔF508-CFTR expression at the plasma membrane. These data suggest that ERp29 is a 4PBA-regulated ER chaperone that regulates WT-CFTR biogenesis and can promote ΔF508-CFTR trafficking in CF epithelial cells. PMID:21525008

ERp29 regulates DeltaF508 and wild-type cystic fibrosis transmembrane conductance regulator (CFTR) trafficking to the plasma membrane in cystic fibrosis (CF) and non-CF epithelial cells.

PubMed

Suaud, Laurence; Miller, Katelyn; Alvey, Lora; Yan, Wusheng; Robay, Amal; Kebler, Catherine; Kreindler, James L; Guttentag, Susan; Hubbard, Michael J; Rubenstein, Ronald C

2011-06-17

Sodium 4-phenylbutyrate (4PBA) improves the intracellular trafficking of ΔF508-CFTR in cystic fibrosis (CF) epithelial cells. The underlying mechanism is uncertain, but 4PBA modulates the expression of some cytosolic molecular chaperones. To identify other 4PBA-regulated proteins that might regulate ΔF508-CFTR trafficking, we performed a differential display RT-PCR screen on IB3-1 CF bronchiolar epithelial cells exposed to 4PBA. One transcript up-regulated by 4PBA encoded ERp29, a luminal resident of the endoplasmic reticulum (ER) thought to be a novel molecular chaperone. We tested the hypothesis that ERp29 is a 4PBA-regulated ER chaperone that influences ΔF508-CFTR trafficking. ERp29 mRNA and protein expression was significantly increased (∼1.5-fold) in 4PBA-treated IB3-1 cells. In Xenopus oocytes, ERp29 overexpression increased the functional expression of both wild-type and ΔF508-CFTR over 3-fold and increased wild-type cystic fibrosis transmembrane conductance regulator (CFTR) plasma membrane expression. In CFBE41o- WT-CFTR cells, expression of and short circuit currents mediated by CFTR decreased upon depletion of ERp29 as did maturation of newly synthesized CFTR. In IB3-1 cells, ΔF508-CFTR co-immunoprecipitated with endogenous ERp29, and overexpression of ERp29 led to increased ΔF508-CFTR expression at the plasma membrane. These data suggest that ERp29 is a 4PBA-regulated ER chaperone that regulates WT-CFTR biogenesis and can promote ΔF508-CFTR trafficking in CF epithelial cells.

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.

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.

A frontal cortex event-related potential driven by the basal forebrain

PubMed Central

Nguyen, David P; Lin, Shih-Chieh

2014-01-01

Event-related potentials (ERPs) are widely used in both healthy and neuropsychiatric conditions as physiological indices of cognitive functions. Contrary to the common belief that cognitive ERPs are generated by local activity within the cerebral cortex, here we show that an attention-related ERP in the frontal cortex is correlated with, and likely generated by, subcortical inputs from the basal forebrain (BF). In rats performing an auditory oddball task, both the amplitude and timing of the frontal ERP were coupled with BF neuronal activity in single trials. The local field potentials (LFPs) associated with the frontal ERP, concentrated in deep cortical layers corresponding to the zone of BF input, were similarly coupled with BF activity and consistently triggered by BF electrical stimulation within 5–10 msec. These results highlight the important and previously unrecognized role of long-range subcortical inputs from the BF in the generation of cognitive ERPs. DOI: http://dx.doi.org/10.7554/eLife.02148.001 PMID:24714497

Spatial and Time Domain Feature of ERP Speller System Extracted via Convolutional Neural Network.

PubMed

Yoon, Jaehong; Lee, Jungnyun; Whang, Mincheol

2018-01-01

Feature of event-related potential (ERP) has not been completely understood and illiteracy problem remains unsolved. To this end, P300 peak has been used as the feature of ERP in most brain-computer interface applications, but subjects who do not show such peak are common. Recent development of convolutional neural network provides a way to analyze spatial and temporal features of ERP. Here, we train the convolutional neural network with 2 convolutional layers whose feature maps represented spatial and temporal features of event-related potential. We have found that nonilliterate subjects' ERP show high correlation between occipital lobe and parietal lobe, whereas illiterate subjects only show correlation between neural activities from frontal lobe and central lobe. The nonilliterates showed peaks in P300, P500, and P700, whereas illiterates mostly showed peaks in around P700. P700 was strong in both subjects. We found that P700 peak may be the key feature of ERP as it appears in both illiterate and nonilliterate subjects.

Spatial and Time Domain Feature of ERP Speller System Extracted via Convolutional Neural Network

PubMed Central

2018-01-01

Feature of event-related potential (ERP) has not been completely understood and illiteracy problem remains unsolved. To this end, P300 peak has been used as the feature of ERP in most brain–computer interface applications, but subjects who do not show such peak are common. Recent development of convolutional neural network provides a way to analyze spatial and temporal features of ERP. Here, we train the convolutional neural network with 2 convolutional layers whose feature maps represented spatial and temporal features of event-related potential. We have found that nonilliterate subjects' ERP show high correlation between occipital lobe and parietal lobe, whereas illiterate subjects only show correlation between neural activities from frontal lobe and central lobe. The nonilliterates showed peaks in P300, P500, and P700, whereas illiterates mostly showed peaks in around P700. P700 was strong in both subjects. We found that P700 peak may be the key feature of ERP as it appears in both illiterate and nonilliterate subjects.

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.

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.

Insights into MHC class I peptide loading from the structure of the tapasin/ERp57 heterodimer

PubMed Central

Dong, Gang; Wearsch, Pamela A.; Peaper, David R.; Cresswell, Peter; Reinisch, Karin M.

2009-01-01

SUMMARY Tapasin is a glycoprotein critical for loading Major Histocompatibility Complex (MHC) class I molecules with high affinity peptides. It functions within the multimeric peptide-loading complex (PLC) as a disulfide-linked, stable heterodimer with the thiol oxidoreductase ERp57, and this covalent interaction is required to support optimal PLC activity. Here we present the 2.6 Å resolution structure of the tapasin/ERp57 core of the PLC. The structure reveals the basis for the stable dimerization of tapasin and ERp57 and provides the first example of a protein disulfide isomerase family member interacting with a substrate. Mutational analysis identified a conserved surface on tapasin that interacts with MHC class I molecules and is critical for the peptide loading and editing function of the tapasin-ERp57 heterodimer. By combining the tapasin/ERp57 structure with those of other defined PLC components we present a molecular model that illuminates the processes involved in MHC class I peptide loading. PMID:19119025

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

The ErpA/NfuA complex builds an oxidation-resistant Fe-S cluster delivery pathway.

PubMed

Py, Béatrice; Gerez, Catherine; Huguenot, Allison; Vidaud, Claude; Fontecave, Marc; Ollagnier de Choudens, Sandrine; Barras, Frédéric

2018-05-18

Fe-S cluster-containing proteins occur in most organisms, wherein they assist in myriad processes from metabolism to DNA repair via gene expression and bioenergetic processes. Here, we used both in vitro and in vivo methods to investigate the capacity of the four Fe-S carriers, NfuA, SufA, ErpA, and IscA, to fulfill their targeting role under oxidative stress. Likewise, Fe-S clusters exhibited varying half-lives, depending on the carriers they were bound to; an NfuA-bound Fe-S cluster was more stable ( t ½ = 100 min) than those bound to SufA ( t ½ = 55 min), ErpA ( t ½ = 54 min), or IscA ( t ½ = 45 min). Surprisingly, the presence of NfuA further enhanced stability of the ErpA-bound cluster to t ½ = 90 min. Using genetic and plasmon surface resonance analyses, we showed that NfuA and ErpA interacted directly with client proteins, whereas IscA or SufA did not. Moreover, NfuA and ErpA interacted with one another. Given all of these observations, we propose an architecture of the Fe-S delivery network in which ErpA is the last factor that delivers cluster directly to most if not all client proteins. NfuA is proposed to assist ErpA under severely unfavorable conditions. A comparison with the strategy employed in yeast and eukaryotes is discussed. © 2018 Py et al.

47 CFR 22.1013 - Effective radiated power limitations.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... The effective radiated power (ERP) of transmitters in the Offshore Radiotelephone Service must not exceed the limits in this section. (a) Maximum power. The ERP of transmitters in this service must not exceed 1000 Watts under any circumstances. (b) Mobile transmitters. The ERP of mobile transmitters must...

47 CFR 22.759 - Power limit for BETRS.

Code of Federal Regulations, 2010 CFR

2010-10-01

... radio systems must not exceed the limits in this section. (a) Maximum ERP. The effective radiated power (ERP) of central office and rural subscriber station transmitters in BETRS must not exceed the applicable limits in this paragraph under any circumstances. Frequency range (MHz) Maximum ERP (watts) 152...

47 CFR 22.759 - Power limit for BETRS.

Code of Federal Regulations, 2011 CFR

2011-10-01

... radio systems must not exceed the limits in this section. (a) Maximum ERP. The effective radiated power (ERP) of central office and rural subscriber station transmitters in BETRS must not exceed the applicable limits in this paragraph under any circumstances. Frequency range (MHz) Maximum ERP (watts) 152...

75 FR 17874 - Digital Audio Broadcasting Systems and Their Impact on the Terrestrial Radio Broadcast Service

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-08

... power (ERP), and implements interference mitigation and remediation procedures to resolve promptly..., and the interference mitigation and remediation procedures will make certain that permissible... ERP to more than 4% of authorized analog ERP. 4. Establishes interference remediation procedures that...

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.

The Influence of Emotional Material on Encoding and Retrieving Intentions: An ERP Study in Younger and Older Adults

PubMed Central

Hering, Alexandra; Kliegel, Matthias; Bisiacchi, Patrizia S.; Cona, Giorgia

2018-01-01

Prospective memory is a cognitive process that comprises the encoding and maintenance of an intention until the appropriate moment of its retrieval. It is of highly relevance for an independent everyday life, especially in older adults; however, there is ample evidence that prospective memory declines with increasing age. Because most studies have used neutral stimuli, it is still an open question how emotional factors influence age-related differences in prospective remembering. The aim of the study was to investigate the influence of emotional material on prospective memory encoding, monitoring, maintaining, and retrieval in younger and older adults using behavioral and electrophysiological measures. We tested 24 younger adults (M = 26.4 years) and 20 older adults (M = 68.1 years) using a picture one-back task as ongoing activity with an embedded prospective memory instruction. The experimental task consisted of three sessions. In each session, participants had to encode series of images that represented the prospective memory cues for the consecutive block. The images were either of pleasant, unpleasant, or neutral valence. The pictures used in the ongoing task were likewise of pleasant, unpleasant, or neutral valence. Event-related potentials (ERPs) were recorded to assess the neural correlates of intention encoding, maintenance, and self-initiated retrieval. We did not find age differences between younger and older adults on the behavioral level. However, the ERP results revealed an interesting pattern that suggested for both age groups elevated attentional processing of emotional cues during encoding indicated by an elevated LPP for the emotional cues. Additionally, younger adults showed increased activity for unpleasant cues. During the maintenance phase, both age groups engaged in strategic monitoring especially for pleasant cues, which led to enhanced sustained positivity. During retrieval, older adults showed increased activity of ERP components related to cue detection and retrieval mainly for pleasant cues indicating enhanced relevance for those cues. In conclusion, emotional material may influence prospective remembering in older adults differently than in younger adults by supporting a mixture of top-down and bottom-up controlled processing. The results demonstrated a negativity bias in younger adults and a positivity bias in older adults. PMID:29503622

Cortical sources of visual evoked potentials during consciousness of executive processes.

PubMed

Babiloni, Claudio; Vecchio, Fabrizio; Iacoboni, Marco; Buffo, Paola; Eusebi, Fabrizio; Rossini, Paolo Maria

2009-03-01

What is the timing of cortical activation related to consciousness of visuo-spatial executive functions? Electroencephalographic data (128 channels) were recorded in 13 adults. Cue stimulus briefly appeared on right or left (equal probability) monitor side for a period, inducing about 50% of recognitions. It was then masked and followed (2 s) by a central visual go stimulus. Left (right) mouse button had to be clicked after right (left) cue stimulus. This "inverted" response indexed executive processes. Afterward, subjects said "seen" if they had detected the cue stimulus or "not seen" when it was missed. Sources of event-related potentials (ERPs) were estimated by LORETA software. The inverted responses were about 95% in seen trials and about 60% in not seen trials. Cue stimulus evoked frontal-parietooccipital potentials, having the same peak latencies in the seen and not seen data. Maximal difference in amplitude of the seen and not seen ERPs was detected at about +300-ms post-stimulus (P3). P3 sources were higher in amplitude in the seen than not seen trials in dorsolateral prefrontal, premotor and parietooccipital areas. This was true in dorsolateral prefrontal and premotor cortex even when percentage of the inverted responses and reaction time were paired in the seen and not seen trials. These results suggest that, in normal subjects, the primary consciousness enhances the efficacy of visuo-spatial executive processes and is sub-served by a late (100- to 400-ms post-stimulus) enhancement of the neural synchronization in frontal areas.

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

ERP index of the morphological family size effect during word recognition.

PubMed

Kwon, Youan; Nam, Kichun; Lee, Yoonhyoung

2012-12-01

The purpose of this study was to examine whether the N400 is affected by the semantic richness of associated neighboring word members or by the density of the orthographic syllable neighborhood. Another purpose of this study was to investigate the source of the different LPC in respect to the semantic richness. To do so, the density of the syllable neighborhood and the size of the morphological family of a word were orthogonally manipulated. ERPs from 24 participants were collected during a go/no-go semantic categorization task. The results showed that the N400 effect was mainly influenced by the density of the syllable neighborhood rather than by the morphological family size. The results also showed that words with a larger morphological family size generate significantly larger LPC than words with a smaller morphological family size. The present study did not support the assumption that the main source of the N400 effect is the semantic richness of the associated neighbors. The present results suggest that the N400 is more sensitive to the density of the syllable neighborhood and LPC is sensitive to the density of the semantic neighborhood reflected by the morphological family size. Copyright © 2012 Elsevier Ltd. All rights reserved.

Excitation of Earth-ionosphere waveguide in the ELF and lower VLF bands by modulated ionospheric current

NASA Astrophysics Data System (ADS)

Field, E. C.; Bloom, R. M.

1993-05-01

In this report, the principal of reciprocity is used in conjunction with a full-wave propagation code to calculate ground-level fields excited by ionospheric currents modulated at frequencies between 50 and 100 Hz with HF heaters. Results show the dependence on source orientation, altitude, and dimension and therefore pertain to experiments using the HIPAS or HAARP ionospheric heaters. In the end-fire mode, the waveguide excitation efficiency of an ELF HED in the ionosphere is up to 20 dB greater than for a ground-based antenna, provided its altitude does not exceed 80 to 90 km. The highest efficiency occurs for a source altitude of around 70 km; if that altitude is raised to 100 km, the efficiency drops by about 20 dB in the day and 10 dB at night. That efficiency does not account for the greater conductivity modulation that might be achieved at altitudes greater than 70 km, however. The trade-off between the altitude dependencies of the excitation efficiency and maximum achievable modulation depends on the ERP of the HF heater, the optimum altitude increasing with increasing ERP. For HIPAS the best modulation altitude is around 70 km, whereas for HAARP there might be marginal value in modulating at attitudes as high as 100 km.

ERP Project Management Lessons Learned

ERIC Educational Resources Information Center

Carroll, Timothy D.

2009-01-01

Implementing an enterprise resource planning (ERP) system is a major undertaking for any higher education institution, with many challenges along the way. More than three years ago, Roane State Community College began a journey to implement an ERP system. Roane State recently completed a very successful implementation of the SunGard Banner Student…

Stay on the ERP Treadmill!

ERIC Educational Resources Information Center

Panettieri, Joseph C.

2007-01-01

This article discusses University of Central Florida's proactive approach to enterprise resource planning (ERP) and highlights UCF's success with ERP. The article points out that much of this success comes from the strength and management experience of those in leadership positions at UCF, and from the expertise and strong credentials of the team…

30 CFR 75.1507 - Emergency Response Plan; refuge alternatives.

Code of Federal Regulations, 2011 CFR

2011-07-01

....1507 Emergency Response Plan; refuge alternatives. (a) The Emergency Response Plan (ERP) shall include... request and the District Manager may approve an alternative location in the ERP if mining involves two... constructed prior to an event in a secure space and an isolated atmosphere, the ERP shall specify that— (1...

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…

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…

Neural Dynamics Underlying Event-Related Potentials

NASA Technical Reports Server (NTRS)

Shah, Ankoor S.; Bressler, Steven L.; Knuth, Kevin H.; Ding, Ming-Zhou; Mehta, Ashesh D.; Ulbert, Istvan; Schroeder, Charles E.

2003-01-01

There are two opposing hypotheses about the brain mechanisms underlying sensory event-related potentials (ERPs). One holds that sensory ERPs are generated by phase resetting of ongoing electroencephalographic (EEG) activity, and the other that they result from signal averaging of stimulus-evoked neural responses. We tested several contrasting predictions of these hypotheses by direct intracortical analysis of neural activity in monkeys. Our findings clearly demonstrate evoked response contributions to the sensory ERP in the monkey, and they suggest the likelihood that a mixed (Evoked/Phase Resetting) model may account for the generation of scalp ERPs in humans.

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.

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.

Trust at first sight: evidence from ERPs.

PubMed

Marzi, Tessa; Righi, Stefania; Ottonello, Sara; Cincotta, Massimo; Viggiano, Maria Pia

2014-01-01

We used event-related potentials (ERPs) to tap the temporal dynamics of first impressions based on face appearance. Participants were asked to evaluate briefly presented faces for trustworthiness and political choice. Behaviorally, participants were better at discriminating faces that were pre-rated as untrustworthy. The ERP results showed that the P100 component was enhanced for untrustworthy faces, consistently with the view that signals of potential threat are given precedence in neural processing. The enhanced ERP responses to untrustworthy faces persisted throughout the processing sequence and the amplitude of early posterior negativity (EPN), and subsequent late positive potential (LPP) was increased with respect to trustworthy faces which, in contrast, elicited an enhanced positivity around 150 ms on frontal sites. These ERP patterns were found specifically for the trustworthiness evaluation and not for the political decision task. Political decision yielded an increase in the N170 amplitude, reflecting a more demanding and taxing structural encoding. Similar ERP responses, as previously reported in the literature for facial expressions processing, were found throughout the entire time course specifically elicited by faces explicitly judged as untrustworthy. One possibility might be that evolution has provided the brain with a 'special toolkit' for trust evaluation that is fast and triggers ERPs related to emotional processing.

Differences in Social Decision-Making between Proposers and Responders during the Ultimatum Game: An EEG Study.

PubMed

Horat, Sibylle K; Prévot, Anne; Richiardi, Jonas; Herrmann, François R; Favre, Grégoire; Merlo, Marco C G; Missonnier, Pascal

2017-01-01

The Ultimatum Game (UG) is a typical paradigm to investigate social decision-making. Although the behavior of humans in this task is already well established, the underlying brain processes remain poorly understood. Previous investigations using event-related potentials (ERPs) revealed three major components related to cognitive processes in participants engaged in the responder condition, the early ERP component P2, the feedback-related negativity (FRN) and a late positive wave (late positive component, LPC). However, the comparison of the ERP waveforms between the responder and proposer conditions has never been studied. Therefore, to investigate condition-related electrophysiological changes, we applied the UG paradigm and compared parameters of the P2, LPC and FRN components in twenty healthy participants. For the responder condition, we found a significantly decreased amplitude and delayed latency for the P2 component, whereas the mean amplitudes of the LPC and FRN increased compared to the proposer condition. Additionally, the proposer condition elicited an early component consisting of a negative deflection around 190 ms, in the upward slope of the P2, probably as a result of early conflict-related processing. Using independent component analysis (ICA), we extracted one functional component time-locked to this deflection, and with source reconstruction (LAURA) we found the anterior cingulate cortex (ACC) as one of the underlying sources. Overall, our findings indicate that intensity and time-course of neuronal systems engaged in the decision-making processes diverge between both UG conditions, suggesting differential cognitive processes. Understanding the electrophysiological bases of decision-making and social interactions in controls could be useful to further detect which steps are impaired in psychiatric patients in their ability to attribute mental states (such as beliefs, intents, or desires) to oneself and others. This ability is called mentalizing (also known as theory of mind).

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.

Multi-Tasking and Choice of Training Data Influencing Parietal ERP Expression and Single-Trial Detection-Relevance for Neuroscience and Clinical Applications.

PubMed

Kirchner, Elsa A; Kim, Su Kyoung

2018-01-01

Event-related potentials (ERPs) are often used in brain-computer interfaces (BCIs) for communication or system control for enhancing or regaining control for motor-disabled persons. Especially results from single-trial EEG classification approaches for BCIs support correlations between single-trial ERP detection performance and ERP expression. Hence, BCIs can be considered as a paradigm shift contributing to new methods with strong influence on both neuroscience and clinical applications. Here, we investigate the relevance of the choice of training data and classifier transfer for the interpretability of results from single-trial ERP detection. In our experiments, subjects performed a visual-motor oddball task with motor-task relevant infrequent ( targets ), motor-task irrelevant infrequent ( deviants ), and motor-task irrelevant frequent ( standards ) stimuli. Under dual-task condition, a secondary senso-motor task was performed, compared to the simple-task condition. For evaluation, average ERP analysis and single-trial detection analysis with different numbers of electrodes were performed. Further, classifier transfer was investigated between simple and dual task. Parietal positive ERPs evoked by target stimuli (but not by deviants) were expressed stronger under dual-task condition, which is discussed as an increase of task emphasis and brain processes involved in task coordination and change of task set. Highest classification performance was found for targets irrespective whether all 62, 6 or 2 parietal electrodes were used. Further, higher detection performance of targets compared to standards was achieved under dual-task compared to simple-task condition in case of training on data from 2 parietal electrodes corresponding to results of ERP average analysis. Classifier transfer between tasks improves classification performance in case that training took place on more varying examples (from dual task). In summary, we showed that P300 and overlaying parietal positive ERPs can successfully be detected while subjects are performing additional ongoing motor activity. This supports single-trial detection of ERPs evoked by target events to, e.g., infer a patient's attentional state during therapeutic intervention.

Multi-Tasking and Choice of Training Data Influencing Parietal ERP Expression and Single-Trial Detection—Relevance for Neuroscience and Clinical Applications

PubMed Central

Kirchner, Elsa A.; Kim, Su Kyoung

2018-01-01

Event-related potentials (ERPs) are often used in brain-computer interfaces (BCIs) for communication or system control for enhancing or regaining control for motor-disabled persons. Especially results from single-trial EEG classification approaches for BCIs support correlations between single-trial ERP detection performance and ERP expression. Hence, BCIs can be considered as a paradigm shift contributing to new methods with strong influence on both neuroscience and clinical applications. Here, we investigate the relevance of the choice of training data and classifier transfer for the interpretability of results from single-trial ERP detection. In our experiments, subjects performed a visual-motor oddball task with motor-task relevant infrequent (targets), motor-task irrelevant infrequent (deviants), and motor-task irrelevant frequent (standards) stimuli. Under dual-task condition, a secondary senso-motor task was performed, compared to the simple-task condition. For evaluation, average ERP analysis and single-trial detection analysis with different numbers of electrodes were performed. Further, classifier transfer was investigated between simple and dual task. Parietal positive ERPs evoked by target stimuli (but not by deviants) were expressed stronger under dual-task condition, which is discussed as an increase of task emphasis and brain processes involved in task coordination and change of task set. Highest classification performance was found for targets irrespective whether all 62, 6 or 2 parietal electrodes were used. Further, higher detection performance of targets compared to standards was achieved under dual-task compared to simple-task condition in case of training on data from 2 parietal electrodes corresponding to results of ERP average analysis. Classifier transfer between tasks improves classification performance in case that training took place on more varying examples (from dual task). In summary, we showed that P300 and overlaying parietal positive ERPs can successfully be detected while subjects are performing additional ongoing motor activity. This supports single-trial detection of ERPs evoked by target events to, e.g., infer a patient's attentional state during therapeutic intervention. PMID:29636660

A new method to detect event-related potentials based on Pearson's correlation.

PubMed

Giroldini, William; Pederzoli, Luciano; Bilucaglia, Marco; Melloni, Simone; Tressoldi, Patrizio

2016-12-01

Event-related potentials (ERPs) are widely used in brain-computer interface applications and in neuroscience.  Normal EEG activity is rich in background noise, and therefore, in order to detect ERPs, it is usually necessary to take the average from multiple trials to reduce the effects of this noise.  The noise produced by EEG activity itself is not correlated with the ERP waveform and so, by calculating the average, the noise is decreased by a factor inversely proportional to the square root of N , where N is the number of averaged epochs. This is the easiest strategy currently used to detect ERPs, which is based on calculating the average of all ERP's waveform, these waveforms being time- and phase-locked.  In this paper, a new method called GW6 is proposed, which calculates the ERP using a mathematical method based only on Pearson's correlation. The result is a graph with the same time resolution as the classical ERP and which shows only positive peaks representing the increase-in consonance with the stimuli-in EEG signal correlation over all channels.  This new method is also useful for selectively identifying and highlighting some hidden components of the ERP response that are not phase-locked, and that are usually hidden in the standard and simple method based on the averaging of all the epochs.  These hidden components seem to be caused by variations (between each successive stimulus) of the ERP's inherent phase latency period (jitter), although the same stimulus across all EEG channels produces a reasonably constant phase. For this reason, this new method could be very helpful to investigate these hidden components of the ERP response and to develop applications for scientific and medical purposes. Moreover, this new method is more resistant to EEG artifacts than the standard calculations of the average and could be very useful in research and neurology.  The method we are proposing can be directly used in the form of a process written in the well-known Matlab programming language and can be easily and quickly written in any other software language.

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.

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

47 CFR 22.1013 - Effective radiated power limitations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... not exceed 100 Watts. The ERP of mobile transmitters, when located within 32 kilometers (20 miles) of the 4.8 kilometer (3 mile) limit, must not exceed 25 Watts. The ERP of airborne mobile stations must.... The ERP of offshore stations located within 128.8 kilometers (80 miles) of the main transmitter...

47 CFR 22.1013 - Effective radiated power limitations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... not exceed 100 Watts. The ERP of mobile transmitters, when located within 32 kilometers (20 miles) of the 4.8 kilometer (3 mile) limit, must not exceed 25 Watts. The ERP of airborne mobile stations must.... The ERP of offshore stations located within 128.8 kilometers (80 miles) of the main transmitter...

The Strategic Academic Enterprise: Why ERPs Will No Longer Be Adequate

ERIC Educational Resources Information Center

Jones, Mary

2009-01-01

In the 1970s and '80s, manufacturing firms began purchasing centralized administrative software--"Enterprise Resource Planning (ERP) systems"--to support their infrastructure needs. In the 1990s, higher education adopted the term ERP to define the back-office systems used by institutions to meet their most pressing business needs--typically those…

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…

Drivers and Effects of Enterprise Resource Planning Post-Implementation Learning

ERIC Educational Resources Information Center

Chang, Hsiu-Hua; Chou, Huey-Wen

2011-01-01

The use of enterprise resource planning (ERP) systems has grown enormously since 1990, but the failure to completely learn how to use them continues to produce disappointing results. Today's rapidly changing business environment and the integrative applications of ERP systems force users to continuously learn new skills after ERP implementation.…

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…

47 CFR 90.303 - Availability of frequencies.

Code of Federal Regulations, 2011 CFR

2011-10-01

...)(2)(ii) of this section, base stations shall be limited to a maximum effective radiated power (ERP... Kull, and Arthur Kill, the maximum ERP and antenna height shall be limited to the entries specified in....0″ W). (iii) Mobile stations shall be limited to 100 watts ERP in areas of operation extending...

47 CFR 22.565 - Transmitting power limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... channels listed in § 22.561 must not exceed the limits in this section. (a) Maximum ERP. The effective radiated power (ERP) of base and fixed transmitters must not exceed the applicable limits in this paragraph under any circumstances. Frequency range (MHz) Maximum ERP (watts) 152-153 1400 157-159 150 454-455 3500...

14 CFR 431.45 - Mishap investigation plan and emergency response plan.

Code of Federal Regulations, 2011 CFR

2011-01-01

... shall also submit an emergency response plan (ERP) that contains procedures for informing the affected public of a planned RLV mission. An acceptable ERP satisfies the requirements of paragraph (e) of this section. The MIP and ERP shall be signed by an individual authorized to sign and certify the application...

47 CFR 22.565 - Transmitting power limits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... channels listed in § 22.561 must not exceed the limits in this section. (a) Maximum ERP. The effective radiated power (ERP) of base and fixed transmitters must not exceed the applicable limits in this paragraph under any circumstances. Frequency range (MHz) Maximum ERP (watts) 152-153 1400 157-159 150 454-455 3500...

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…

Temporal Dynamics of Awareness for Facial Identity Revealed with ERP

ERIC Educational Resources Information Center

Genetti, Melanie; Khateb, Asaid; Heinzer, Severine; Michel, Christoph M.; Pegna, Alan J.

2009-01-01

In this study, we investigated the scalp recorded event-related potential (ERP) responses related to visual awareness. A backward masking procedure was performed while high-density EEG recordings were carried out. Subjects were asked to detect a familiar face, presented at durations that varied parametrically between 16 and 266 ms. ERPs were…

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…

To Use or Not to Use--ERP Resistance Is the Question: The Roles of Tacit Knowledge and Complexity

ERIC Educational Resources Information Center

Freeze, Ronald D.; Schmidt, Pamela J.

2015-01-01

Enterprise Resource Planning (ERP) systems in business environments demand multidisciplinary understanding and collaboration between functional departments. The traditional educational paradigm isolates the learning of each functional discipline as if business people operated in functional isolation. ERP system value can only be realized by…

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.

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.

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

Mapping the ER Interactome: The P Domains of Calnexin and Calreticulin as Plurivalent Adapters for Foldases and Chaperones.

PubMed

Kozlov, Guennadi; Muñoz-Escobar, Juliana; Castro, Karla; Gehring, Kalle

2017-09-05

The lectin chaperones calreticulin (CRT) and calnexin (CNX) contribute to the folding of glycoproteins in the ER by recruiting foldases such as the protein disulfide isomerase ERp57 and the peptidyl prolyl cis-trans isomerase CypB. Recently, CRT was shown to interact with the chaperone ERp29. Here, we show that ERp29 directly binds to the P domain of CNX. Crystal structures of the D domain of ERp29 in complex with the P domains from CRT and calmegin, a tissue-specific CNX homolog, reveal a commonality in the mechanism of binding whereby the tip of the P domain functions as a plurivalent adapter to bind a variety of folding factors. We show that mutation of a single residue, D348 in CNX, abrogates binding to ERp29 as well as ERp57 and CypB. The structural diversity of the accessory factors suggests that these chaperones became specialized for glycoprotein folding through convergent evolution of their P-domain binding sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of a movie soundtrack on auditory event-related potentials in children, adolescents, and adults.

PubMed

Mahajan, Yatin; McArthur, Genevieve

2011-05-01

To determine if an audible movie soundtrack has a degrading effect on the auditory P1, N1, P2, N2, or mismatch negativity (MMN) event-related potentials (ERPs) in children, adolescents, or adults. The auditory ERPs of 36 children, 32 young adolescents, 19 older adolescents, and 10 adults were measured while they watched a movie in two conditions: with an audible soundtrack and with a silent soundtrack. In children and adolescents, the audible movie soundtrack had a significant impact on amplitude, latency or split-half reliability of the N1, P2, N2, and MMN ERPs. The audible soundtrack had minimal impact on the auditory ERPs of adults. These findings challenge previous claims that an audible soundtrack does not degrade the auditory ERPs of children. Further, the reliability of the MMN is poorer than P1, N1, P2, and N2 peaks in both sound-off and sound-on conditions. Researchers should be cautious about using an audible movie soundtrack when measuring auditory ERPs in younger listeners. Copyright © 2010 International Federation of Clinical Neurophysiology. All rights reserved.

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.

Effect of Aging on ERP Components of Cognitive Control

PubMed Central

Kropotov, Juri; Ponomarev, Valery; Tereshchenko, Ekaterina P.; Müller, Andreas; Jäncke, Lutz

2016-01-01

As people age, their performance on tasks requiring cognitive control often declines. Such a decline is frequently explained as either a general or specific decline in cognitive functioning with age. In the context of hypotheses suggesting a general decline, it is often proposed that processing speed generally declines with age. A further hypothesis is that an age-related compensation mechanism is associated with a specific cognitive decline. One prominent theory is the compensation hypothesis, which proposes that deteriorated functions are compensated for by higher performing functions. In this study, we used event-related potentials (ERPs) in the context of a GO/NOGO task to examine the age-related changes observed during cognitive control in a large group of healthy subjects aged between 18 and 84 years. The main question we attempted to answer was whether we could find neurophysiological support for either a general decline in processing speed or a compensation strategy. The subjects performed a relatively demanding cued GO/NOGO task with similar omissions and reaction times across the five age groups. The ERP waves of cognitive control, such as N2, P3cue and CNV, were decomposed into latent components by means of a blind source separation method. Based on this decomposition, it was possible to more precisely delineate the different neurophysiological and psychological processes involved in cognitive control. These data support the processing speed hypothesis because the latencies of all cognitive control ERP components increased with age, by 8 ms per decade for the early components (<200 ms) and by 20 ms per decade for the late components. At the same time, the compensatory hypothesis of aging was also supported, as the amplitudes of the components localized in posterior brain areas decreased with age, while those localized in the prefrontal cortical areas increased with age in order to maintain performance on this simple task at a relatively stable level. PMID:27092074

Temporal Dynamics of Visual Attention Measured with Event-Related Potentials

PubMed Central

Kashiwase, Yoshiyuki; Matsumiya, Kazumichi; Kuriki, Ichiro; Shioiri, Satoshi

2013-01-01

How attentional modulation on brain activities determines behavioral performance has been one of the most important issues in cognitive neuroscience. This issue has been addressed by comparing the temporal relationship between attentional modulations on neural activities and behavior. Our previous study measured the time course of attention with amplitude and phase coherence of steady-state visual evoked potential (SSVEP) and found that the modulation latency of phase coherence rather than that of amplitude was consistent with the latency of behavioral performance. In this study, as a complementary report, we compared the time course of visual attention shift measured by event-related potentials (ERPs) with that by target detection task. We developed a novel technique to compare ERPs with behavioral results and analyzed the EEG data in our previous study. Two sets of flickering stimulus at different frequencies were presented in the left and right visual hemifields, and a target or distracter pattern was presented randomly at various moments after an attention-cue presentation. The observers were asked to detect targets on the attended stimulus after the cue. We found that two ERP components, P300 and N2pc, were elicited by the target presented at the attended location. Time-course analyses revealed that attentional modulation of the P300 and N2pc amplitudes increased gradually until reaching a maximum and lasted at least 1.5 s after the cue onset, which is similar to the temporal dynamics of behavioral performance. However, attentional modulation of these ERP components started later than that of behavioral performance. Rather, the time course of attentional modulation of behavioral performance was more closely associated with that of the concurrently recorded SSVEPs analyzed. These results suggest that neural activities reflected not by either the P300 or N2pc, but by the SSVEPs, are the source of attentional modulation of behavioral performance. PMID:23976966

Sports training enhances visuo-spatial cognition regardless of open-closed typology

PubMed Central

Hsieh, Shu-Shih; Chen, Kuan-Fu; Chang, Yu-Kai

2017-01-01

The aim of this study was to investigate the effects of open and closed sport participation on visuo-spatial attention and memory performance among young adults. Forty-eight young adults—16 open-skill athletes, 16 closed-skill athletes, and 16 non-athletes controls—were recruited for the study. Both behavioral performance and event-related potential (ERP) measurement were assessed when participants performed non-delayed and delayed match-to-sample task that tested visuo-spatial attention and memory processing. Results demonstrated that regardless of training typology, the athlete groups exhibited shorter reaction times in both the visuo-spatial attention and memory conditions than the control group with no existence of speed-accuracy trade-off. Similarly, a larger P3 amplitudes were observed in both athlete groups than in the control group for the visuo-spatial memory condition. These findings suggest that sports training, regardless of typology, are associated with superior visuo-spatial attention and memory performance, and more efficient neural resource allocation in memory processing. PMID:28560098

Event-related potentials to structural familiar face incongruity processing.

PubMed

Jemel, B; George, N; Olivares, E; Fiori, N; Renault, B

1999-07-01

Thirty scalp sites were used to investigate the specific topography of the event-related potentials (ERPs) related to face associative priming when masked eyes of familiar faces were completed with either the proper features or incongruent ones. The enhanced negativity of N210 and N350, due to structural incongruity of faces, have a "category specific" inferotemporal localization on the scalp. Additional analyses support the existence of multiple ERP features within the temporal interval typically associated with N400 (N350 and N380), involving occipitotemporal and centroparietal areas. Seven reliable dipole locations have been evidenced using the brain electrical source analysis algorithm. Some of these localizations (fusiform, parahippocampal) are already known to be involved in face recognition, the other ones being related to general cognitive processes related to the task's demand. Because of their specific topography, the observed effects suggest that the face structural congruency process might involve early specialized neocortical areas in parallel with cortical memory circuits in the integration of perceptual and cognitive face processing.

Elements of person knowledge: Episodic recollection helps us to identify people but not to recognize their faces.

PubMed

MacKenzie, Graham; Donaldson, David I

2016-12-01

Faces automatically draw attention, allowing rapid assessments of personality and likely behaviour. How we respond to people is, however, highly dependent on whether we know who they are. According to face processing models person knowledge comes from an extended neural system that includes structures linked to episodic memory. Here we use scalp recorded brain signals to demonstrate the specific role of episodic memory processes during face processing. In two experiments we recorded Event-Related Potentials (ERPs) while participants made identify, familiar or unknown responses to famous faces. ERPs revealed neural signals previously associated with episodic recollection for identify but not familiar faces. These findings provide novel evidence suggesting that recollection is central to face processing, providing one source of person knowledge that can be used to moderate the initial impressions gleaned from the core neural system that supports face recognition. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

History of concussion impacts electrophysiological correlates of working memory.

PubMed

Hudac, Caitlin M; Cortesa, Cathryn S; Ledwidge, Patrick S; Molfese, Dennis L

2017-10-10

Sports-related concussions occur in approximately 21% of college athletes with implications for long-term cognitive impairments in working memory. Working memory involves the capacity to maintain short-term information and integrate with higher-order cognitive processing for planning and behavior execution, critical skills for optimal cognitive and athletic performance. This study quantified working memory impairments in 36 American football college athletes (18-23years old) using event-related potentials (ERPs). Despite performing similarly in a standard 2-back working memory task, athletes with history of concussion exhibited larger P1 and P3 amplitudes compared to Controls. Concussion History group latencies were slower for the P1 and faster for the N2. Source estimation analyses indicated that previously concussed athletes engaged different brain regions compared to athletes with no concussion history. These findings suggest that ERPs may be a sensitive and objective measure to detect long-term cognitive consequences of concussion. Copyright © 2017 Elsevier B.V. All rights reserved.

Event-related Potentials During Target-response Tasks to Study Cognitive Processes of Upper Limb Use in Children with Unilateral Cerebral Palsy.

PubMed

Zielinski, Ingar Marie; Steenbergen, Bert; Baas, C Marjolein; Aarts, Pauline; Jongsma, Marijtje L A

2016-01-11

Unilateral Cerebral Palsy (CP) is a neurodevelopmental disorder that is a very common cause of disability in childhood. It is characterized by unilateral motor impairments that are frequently dominated in the upper limb. In addition to a reduced movement capacity of the affected upper limb, several children with unilateral CP show a reduced awareness of the remaining movement capacity of that limb. This phenomenon of disregarding the preserved capacity of the affected upper limb is regularly referred to as Developmental Disregard (DD). Different theories have been postulated to explain DD, each suggesting slightly different guidelines for therapy. Still, cognitive processes that might additionally contribute to DD in children with unilateral CP have never been directly studied. The current protocol was developed to study cognitive aspects involved in upper limb control in children with unilateral CP with and without DD. This was done by recording event-related potentials (ERPs) extracted from the ongoing EEG during target-response tasks asking for a hand-movement response. ERPs consist of several components, each of them associated with a well-defined cognitive process (e.g., the N1 with early attention processes, the N2 with cognitive control and the P3 with cognitive load and mental effort). Due to its excellent temporal resolution, the ERP technique enables to study several covert cognitive processes preceding overt motor responses and thus allows insight into the cognitive processes that might contribute to the phenomenon of DD. Using this protocol adds a new level of explanation to existing behavioral studies and opens new avenues to the broader implementation of research on cognitive aspects of developmental movement restrictions in children.

Induced theta oscillations as biomarkers for alcoholism.

PubMed

Andrew, Colin; Fein, George

2010-03-01

Studies have suggested that non-phase-locked event-related oscillations (ERO) in target stimulus processing might provide biomarkers of alcoholism. This study investigates the discriminatory power of non-phase-locked oscillations in a group of long-term abstinent alcoholics (LTAAs) and non-alcoholic controls (NACs). EEGs were recorded from 48 LTAAs and 48 age and gender comparable NACs during rest with eyes open (EO) and during the performance of a three-condition visual target detection task. The data were analyzed to extract resting power, ERP amplitude and non-phase-locked ERO power measures. Data were analyzed using MANCOVA to determine the discriminatory power of induced theta ERO vs. resting theta power vs. P300 ERP measures in differentiating the LTAA and NAC groups. Both groups showed significantly more theta power in the pre-stimulus reference period of the task vs. the resting EO condition. The resting theta power did not discriminate the groups, while the LTAAs showed significantly less pre-stimulus theta power vs. the NACs. The LTAAs showed a significantly larger theta event-related synchronization (ERS) to the target stimulus vs. the NACs, even after accounting for pre-stimulus theta power levels. ERS to non-target stimuli showed smaller induced oscillations vs. target stimuli with no group differences. Alcohol use variables, a family history of alcohol problems, and the duration of alcohol abstinence were not associated with any theta power measures. While reference theta power in the task and induced theta oscillations to target stimuli both discriminate LTAAs and NACs, induced theta oscillations better discriminate the groups. Induced theta power measures are also more powerful and independent group discriminators than the P3b amplitude. Induced frontal theta oscillations promise to provide biomarkers of alcoholism that complement the well-established P300 ERP discriminators.

Effect of ecological restoration programs on dust concentrations in the North China Plain: a case study

NASA Astrophysics Data System (ADS)

Long, Xin; Tie, Xuexi; Li, Guohui; Cao, Junji; Feng, Tian; Zhao, Shuyu; Xing, Li; An, Zhisheng

2018-05-01

In recent decades, the Chinese government has made a great effort in initiating large-scale ecological restoration programs (ERPs) to reduce the dust concentrations in China, especially for dust storm episodes. Using the Moderate Resolution Imaging Spectroradiometer (MODIS) land cover product, the ERP-induced land cover changes are quantitatively evaluated in this study. Two obvious vegetation protective barriers arise throughout China from the southwest to the northeast, which are well known as the Green Great Wall (GGW). Both the grass GGW and forest GGW are located between the dust source region (DSR) and the densely populated North China Plain (NCP). To assess the effect of ERPs on dust concentrations, a regional transport/dust model (WRF-DUST, Weather Research and Forecast model with dust) is applied to investigate the evolution of dust plumes during a strong dust storm episode from 2 to 8 March 2016. The WRF-DUST model generally performs reasonably well in reproducing the temporal variations and spatial distributions of near-surface [PMC] (mass concentration of particulate matter with aerodynamic diameter between 2.5 and 10 µm) during the dust storm event. Sensitivity experiments have indicated that the ERP-induced GGWs help to reduce the dust concentration in the NCP, especially in BTH (Beijing, Tianjin, and Hebei). When the dust storm is transported from the upwind DSR to the downwind NCP, the [PMC] reduction ranges from -5 to -15 % in the NCP, with a maximum reduction of -12.4 % (-19.2 µg m-3) in BTH and -7.6 % (-10.1 µg m-3) in the NCP. We find the dust plumes move up to the upper atmosphere and are transported from the upwind DSR to the downwind NCP, accompanied by dust decrease. During the episode, the forest GGW is nonsignificant in dust concentration control because it is of benefit for dry deposition and not for emission. Conversely, the grass GGW is beneficial in controlling dust erosion and is the dominant reason for [PMC] decrease in the NCP. Because the air pollution is severe in eastern China, especially in the NCP, and the contribution of dust episodes is significant, the reduction of dust concentrations will have important effects on severe air pollution. This study illustrates the considerable contribution of ERPs to the control of air pollution in China, especially in springtime.

Enterprise resource planning for hospitals.

PubMed

van Merode, Godefridus G; Groothuis, Siebren; Hasman, Arie

2004-06-30

Integrated hospitals need a central planning and control system to plan patients' processes and the required capacity. Given the changes in healthcare one can ask the question what type of information systems can best support these healthcare delivery organizations. We focus in this review on the potential of enterprise resource planning (ERP) systems for healthcare delivery organizations. First ERP systems are explained. An overview is then presented of the characteristics of the planning process in hospital environments. Problems with ERP that are due to the special characteristics of healthcare are presented. The situations in which ERP can or cannot be used are discussed. It is suggested to divide hospitals in a part that is concerned only with deterministic processes and a part that is concerned with non-deterministic processes. ERP can be very useful for planning and controlling the deterministic processes.

Single-trial detection of visual evoked potentials by common spatial patterns and wavelet filtering for brain-computer interface.

PubMed

Tu, Yiheng; Huang, Gan; Hung, Yeung Sam; Hu, Li; Hu, Yong; Zhang, Zhiguo

2013-01-01

Event-related potentials (ERPs) are widely used in brain-computer interface (BCI) systems as input signals conveying a subject's intention. A fast and reliable single-trial ERP detection method can be used to develop a BCI system with both high speed and high accuracy. However, most of single-trial ERP detection methods are developed for offline EEG analysis and thus have a high computational complexity and need manual operations. Therefore, they are not applicable to practical BCI systems, which require a low-complexity and automatic ERP detection method. This work presents a joint spatial-time-frequency filter that combines common spatial patterns (CSP) and wavelet filtering (WF) for improving the signal-to-noise (SNR) of visual evoked potentials (VEP), which can lead to a single-trial ERP-based BCI.

Efficient IgM assembly and secretion require the plasma cell induced endoplasmic reticulum protein pERp1

PubMed Central

van Anken, Eelco; Pena, Florentina; Hafkemeijer, Nicole; Christis, Chantal; Romijn, Edwin P.; Grauschopf, Ulla; Oorschot, Viola M. J.; Pertel, Thomas; Engels, Sander; Ora, Ari; Lástun, Viorica; Glockshuber, Rudi; Klumperman, Judith; Heck, Albert J. R.; Luban, Jeremy; Braakman, Ineke

2009-01-01

Plasma cells daily secrete their own mass in antibodies, which fold and assemble in the endoplasmic reticulum (ER). To reach these levels, cells require pERp1, a novel lymphocyte-specific small ER-resident protein, which attains expression levels as high as BiP when B cells differentiate into plasma cells. Although pERp1 has no homology with known ER proteins, it does contain a CXXC motif typical for oxidoreductases. In steady state, the CXXC cysteines are locked by two parallel disulfide bonds with a downstream C(X)6C motif, and pERp1 displays only modest oxidoreductase activity. pERp1 emerged as a dedicated folding factor for IgM, associating with both heavy and light chains and promoting assembly and secretion of mature IgM. PMID:19805154

Time is of the Essence: A Review of Electroencephalography (EEG) and Event-Related Brain Potentials (ERPs) in Language Research.

PubMed

Beres, Anna M

2017-12-01

The discovery of electroencephalography (EEG) over a century ago has changed the way we understand brain structure and function, in terms of both clinical and research applications. This paper starts with a short description of EEG and then focuses on the event-related brain potentials (ERPs), and their use in experimental settings. It describes the typical set-up of an ERP experiment. A description of a number of ERP components typically involved in language research is presented. Finally, the advantages and disadvantages of using ERPs in language research are discussed. EEG has an extensive use in today's world, including medical, psychology, or linguistic research. The excellent temporal resolution of EEG information allows one to track a brain response in milliseconds and therefore makes it uniquely suited to research concerning language processing.

A comparison between EEG source localization and fMRI during the processing of emotional visual stimuli

NASA Astrophysics Data System (ADS)

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

2007-03-01

The purpose of this paper is to compare between EEG source localization and fMRI during emotional processing. 108 pictures for EEG (categorized as positive, negative and neutral) and 72 pictures for fMRI were presented to 24 healthy, right-handed subjects. The fMRI data were analyzed using statistical parametric mapping with SPM2. LORETA was applied to grand averaged ERP data to localize intracranial sources. Statistical analysis was implemented to compare spatiotemporal activation of fMRI and EEG. The fMRI results are in accordance with EEG source localization to some extent, while part of mismatch in localization between the two methods was also observed. In the future we should apply the method for simultaneous recording of EEG and fMRI to our study.

Developing Brain Vital Signs: Initial Framework for Monitoring Brain Function Changes Over Time

PubMed Central

Ghosh Hajra, Sujoy; Liu, Careesa C.; Song, Xiaowei; Fickling, Shaun; Liu, Luke E.; Pawlowski, Gabriela; Jorgensen, Janelle K.; Smith, Aynsley M.; Schnaider-Beeri, Michal; Van Den Broek, Rudi; Rizzotti, Rowena; Fisher, Kirk; D'Arcy, Ryan C. N.

2016-01-01

Clinical assessment of brain function relies heavily on indirect behavior-based tests. Unfortunately, behavior-based assessments are subjective and therefore susceptible to several confounding factors. Event-related brain potentials (ERPs), derived from electroencephalography (EEG), are often used to provide objective, physiological measures of brain function. Historically, ERPs have been characterized extensively within research settings, with limited but growing clinical applications. Over the past 20 years, we have developed clinical ERP applications for the evaluation of functional status following serious injury and/or disease. This work has identified an important gap: the need for a clinically accessible framework to evaluate ERP measures. Crucially, this enables baseline measures before brain dysfunction occurs, and might enable the routine collection of brain function metrics in the future much like blood pressure measures today. Here, we propose such a framework for extracting specific ERPs as potential “brain vital signs.” This framework enabled the translation/transformation of complex ERP data into accessible metrics of brain function for wider clinical utilization. To formalize the framework, three essential ERPs were selected as initial indicators: (1) the auditory N100 (Auditory sensation); (2) the auditory oddball P300 (Basic attention); and (3) the auditory speech processing N400 (Cognitive processing). First step validation was conducted on healthy younger and older adults (age range: 22–82 years). Results confirmed specific ERPs at the individual level (86.81–98.96%), verified predictable age-related differences (P300 latency delays in older adults, p < 0.05), and demonstrated successful linear transformation into the proposed brain vital sign (BVS) framework (basic attention latency sub-component of BVS framework reflects delays in older adults, p < 0.05). The findings represent an initial critical step in developing, extracting, and characterizing ERPs as vital signs, critical for subsequent evaluation of dysfunction in conditions like concussion and/or dementia. PMID:27242415

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 Electrophysiological Signature of Remember-Know Is Confounded with Memory Strength and Cannot Be Interpreted as Evidence for Dual-process Theory of Recognition.

PubMed

Brezis, Noam; Bronfman, Zohar Z; Yovel, Galit; Goshen-Gottstein, Yonatan

2017-02-01

The quantity and nature of the processes underlying recognition memory remains an open question. A majority of behavioral, neuropsychological, and brain studies have suggested that recognition memory is supported by two dissociable processes: recollection and familiarity. It has been conversely argued, however, that recollection and familiarity map onto a single continuum of mnemonic strength and hence that recognition memory is mediated by a single process. Previous electrophysiological studies found marked dissociations between recollection and familiarity, which have been widely held as corroborating the dual-process account. However, it remains unknown whether a strength interpretation can likewise apply for these findings. Here we describe an ERP study, using a modified remember-know (RK) procedure, which allowed us to control for mnemonic strength. We find that ERPs of high and low mnemonic strength mimicked the electrophysiological distinction between R and K responses, in a lateral positive component (LPC), 500-1000 msec poststimulus onset. Critically, when contrasting strength with RK experience, by comparing weak R to strong K responses, the electrophysiological signal mapped onto strength, not onto subjective RK experience. Invoking the LPC as support for dual-process accounts may, therefore, be amiss.

Electrophysiological evidence for phenomenal consciousness.

PubMed

Revonsuo, Antti; Koivisto, Mika

2010-09-01

Abstract Recent evidence from event-related brain potentials (ERPs) lends support to two central theses in Lamme's theory. The earliest ERP correlate of visual consciousness appears over posterior visual cortex around 100-200 ms after stimulus onset. Its scalp topography and time window are consistent with recurrent processing in the visual cortex. This electrophysiological correlate of visual consciousness is mostly independent of later ERPs reflecting selective attention and working memory functions. Overall, the ERP evidence supports the view that phenomenal consciousness of a visual stimulus emerges earlier than access consciousness, and that attention and awareness are served by distinct neural processes.

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.

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.

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.

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.

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

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…

Effects of Rhyme and Spelling Patterns on Auditory Word ERPs Depend on Selective Attention to Phonology

ERIC Educational Resources Information Center

Yoncheva, Yuliya N.; Maurer, Urs; Zevin, Jason D.; McCandliss, Bruce D.

2013-01-01

ERP responses to spoken words are sensitive to both rhyming effects and effects of associated spelling patterns. Are such effects automatically elicited by spoken words or dependent on selectively attending to phonology? To address this question, ERP responses to spoken word pairs were investigated under two equally demanding listening tasks that…

The Drivers of ERP Implementation and Its Impact on Organizational Capabilities and Performance and Customer Value

ERIC Educational Resources Information Center

Hwang, Woosang

2011-01-01

In a constantly changing global business environment, firms have no other choice but to continually expand their capabilities and sharpen their competitive edge. Toward this goal, an increasing number of organizations are turning to Enterprise Resource Planning (ERP) systems. An ERP system utilizes various kinds of information processing…

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…

Factors Influencing Post-Adoptive Enterprise Resource Planning (ERP) Utilization

ERIC Educational Resources Information Center

McGinnis, Thomas C.

2011-01-01

Organizations expend a great deal of time, effort and money on the implementation of enterprise resource planning (ERP) systems. They are considered the price of entry for large organizations to do business. Yet the success rate of ERP systems is poor. IS literature suggests that one possible reason for this is the underutilization of these…

47 CFR 90.545 - TV/DTV interference protection criteria.

Code of Federal Regulations, 2011 CFR

2011-10-01

... contour (41 dBµV/m) (88.5 kilometers or 55.0 miles) of the DTV station. (b) Maximum ERP and HAAT. The maximum effective radiated power (ERP) and the antenna height above average terrain (HAAT) of the proposed... determined using the methods described in this section. (1) Each base station is limited to a maximum ERP of...

47 CFR 5.85 - Frequencies and policy governing their assignment.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Stations within 4.8 kilometers (3 statute miles) with 50 watts or more average ERP in the primary plane of... statute miles) with 1 kW or more average ERP in the primary plane of polarization in the azimuthal... more average ERP in the primary plane of polarization in the azimuthal direction of the Monitoring...

47 CFR 2.1091 - Radiofrequency radiation exposure evaluation: mobile devices.

Code of Federal Regulations, 2011 CFR

2011-10-01

... their effective radiated power (ERP) is 1.5 watts or more, or if they operate at frequencies above 1.5 GHz and their ERP is 3 watts or more. Unlicensed personal communications service devices, unlicensed... exposure prior to equipment authorization or use if their ERP is 3 watts or more or if they meet the...

47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna Height (EAH) limitations as shown in the table below. ERP is defined as the product of the power supplied to... height above mean sea level. Limits of Effective Radiated Power (ERP) Corresponding to Effective Antenna...

47 CFR 22.911 - Cellular geographic service area.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the SAB is calculated as a function of effective radiated power (ERP) and antenna center of radiation...: d is the radial distance in kilometers h is the radial antenna HAAT in meters p is the radial ERP in... the radial distance in kilometers h is the radial antenna HAAT in meters p is the radial ERP in Watts...

Investigation of ERP Teaching and Practitioner Experiences Related to ISO 9000 Core Standards

ERIC Educational Resources Information Center

Wiggins, Charles

2010-01-01

Enterprise Resource Planning (ERP) systems have greatly enhanced the efficiency and continuity of the business process and the flow of information technology in order to support organizations. ERP was intended to be used as a tool for manufacturing in an effort to build a more cohesive customer relationship. Lately many "Fortune" 500 companies…

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…

Private and Public Sector Enterprise Resource Planning System Post-Implementation Practices: A Comparative Mixed Method Investigation

ERIC Educational Resources Information Center

Bachman, Charles A.

2010-01-01

While private sector organizations have implemented enterprise resource planning (ERP) systems since the mid 1990s, ERP implementations within the public sector lagged by several years. This research conducted a mixed method, comparative assessment of post "go-live" ERP implementations between public and private sector organization. Based on a…

The Impact of Enterprise Resource Planning Systems on Small and Medium Enterprises

ERIC Educational Resources Information Center

Buleje, Miguel A.

2014-01-01

Enterprise resource planning (ERP) systems are considered the price of entry in today's business environment, and the number of small and medium-sized enterprises (SME) retiring legacy systems in favor of ERP systems is increasing exponentially. However, there is a lack of knowledge and awareness of ERP systems and their potential benefit and…

Teaching Tip: Using a Group Role-Play Exercise to Engage Students in Learning Business Processes and ERP

ERIC Educational Resources Information Center

Shen, Yide; Nicholson, Jennifer; Nicholson, Darren

2015-01-01

With the increasing process-centric focus and proliferation of Enterprise Resource Planning (ERP) systems in organizations, it is imperative for business graduates to understand cross-functional business processes and ERP system's role in supporting business processes. However, this topic can be rather abstract and dry to undergraduate students,…

Proceedings of the 1989 Antenna Applications Symposium. Volume 2

DTIC Science & Technology

1990-03-01

together with the power and phase of the four active sources. This information was determined and subsequently compared with recorded ERP. As component...temperature profile T2. Applying the negated RA values as phase shifter commands generates constant phase across the aperture at temperature T1 in...over the band for both cases. The phase prediction was compared to a Touchstone circuit model and the error with respect to this model is plotted in

Selective anterior cingulate cortex deficit during conflict solution in schizophrenia: an event-related potential study.

PubMed

Neuhaus, Andres H; Koehler, Simone; Opgen-Rhein, Carolin; Urbanek, Carsten; Hahn, Eric; Dettling, Michael

2007-10-01

Schizophrenia research has gained a new focus on identification and further characterization of neurocognitive deficits in the search for behavioural endophenotypes of this disorder. The objective of this study was to explore differential cortical processing during executive control in schizophrenia as assessed with the attention network test (ANT). Sixteen schizophrenic patients and sixteen healthy controls matched for gender, age, education, and nicotine consumption were tested with the ANT while recording 29-channel-electroencephalogram (EEG). Visual event-related potentials (ERP) N200 and P300 were topographically analyzed and cortical mapping using low resolution brain electromagnetic tomography (LORETA) was applied to localize neuroelectric generators of ERP. Behaviourally, significant differences between schizophrenic patients and controls were found only for the conflict condition (p<0.05) and for conflict adjusted by mean reaction time (p<0.01). Examining ERP of control subjects, N200 failed to show robust flanker congruency effects. P300 amplitude was reduced at Pz (p<0.05) and P300 latency was increased at Cz (p<0.005) for the conflict condition. Schizophrenic patients differed significantly in P300 latency at Cz during late conflict processing (p<0.005). Source analysis revealed a deficit in anterior cingulate cortex (p<0.05). Our results are in line with previous reports about dysfunctional ACC activation in schizophrenia and argue in favour of a selective deficit of cortical conflict resolution. It is further proposed that dysfunctional ACC activation during executive processing may be a neurophysiologic endophenotype candidate of schizophrenia.

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 sentence wrap-up dogma.

PubMed

Stowe, Laurie A; Kaan, Edith; Sabourin, Laura; Taylor, Ryan C

2018-03-30

Current sentence processing research has focused on early effects of the on-line incremental processes that are performed at each word or constituent during processing. However, less attention has been devoted to what happens at the end of the clause or sentence. More specifically, over the last decade and a half, a lot of effort has been put into avoiding measuring event-related brain potentials (ERPs) at the final word of a sentence, because of the possible effects of sentence wrap-up. This article reviews the evidence on how and when sentence wrap-up impacts behavioral and ERP results. Even though the end of the sentence is associated with a positive-going ERP wave, thus far this effect has not been associated with any factors hypothesized to affect wrap-up. In addition, ERP responses to violations have not been affected by this positivity. "Sentence-final" negativities reported in the literature are not unique to sentence final positions, nor do they obscure or distort ERP effects associated with linguistic manipulations. Finally, the empirical evidence used to argue that sentence-final ERPs are different from those recorded at sentence-medial positions is weak at most. Measuring ERPs at sentence-final positions is therefore certainly not to be avoided at all costs, especially not in cases where the structure of the language under investigation requires it. More importantly, researchers should follow rigorous method in their experimental design, avoid decision tasks which may induce ERP confounds, and ensure all other possible explanations for results are considered. Although this article is directed at a particular dogma from a particular literature, this review shows that it is important to reassess what is regarded as "general knowledge" from time to time. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

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.

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.

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.

Flashing characters with famous faces improves ERP-based brain-computer interface performance

NASA Astrophysics Data System (ADS)

Kaufmann, T.; Schulz, S. M.; Grünzinger, C.; Kübler, A.

2011-10-01

Currently, the event-related potential (ERP)-based spelling device, often referred to as P300-Speller, is the most commonly used brain-computer interface (BCI) for enhancing communication of patients with impaired speech or motor function. Among numerous improvements, a most central feature has received little attention, namely optimizing the stimulus used for eliciting ERPs. Therefore we compared P300-Speller performance with the standard stimulus (flashing characters) against performance with stimuli known for eliciting particularly strong ERPs due to their psychological salience, i.e. flashing familiar faces transparently superimposed on characters. Our results not only indicate remarkably increased ERPs in response to familiar faces but also improved P300-Speller performance due to a significant reduction of stimulus sequences needed for correct character classification. These findings demonstrate a promising new approach for improving the speed and thus fluency of BCI-enhanced communication with the widely used P300-Speller.

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

Analysis on the integration of ERP and e-commerce

NASA Astrophysics Data System (ADS)

Wang, Yongqing; Shi, Yuliana

2017-08-01

With the continuous development of China's modern economic construction, a variety of information technology are emerging. The new economic development characterized by e-commerce has accelerated the globalization of the economy. In face of increasingly fierce market competition, for enterprises, the constructions of ERP and e-commerce are necessary ways to enhance the core competitiveness of enterprises. At present, most of the internal ERP systems and external e-commerce systems are in relatively independent state. However, with the increasing fierce market competition, a single mode of operation has been unable to meet the requirements of enterprise development. Accordingly, the effective integration of ERP and e-commerce in the new era has become one of the most important topics for enterprise development. This paper firstly analyzes the relationship between ERP and e-commerce, and then analyzes the necessity and feasibility of integration, and finally discusses the integration strategies and technologies.

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

Motivated attention and family risk for depression: Neuronal generator patterns at scalp elicited by lateralized aversive pictures reveal blunted emotional responsivity.

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

2017-01-01

Behavioral and electrophysiologic evidence suggests that major depression (MDD) involves right parietotemporal dysfunction, a region activated by arousing affective stimuli. Building on prior event-related potential (ERP) findings (Kayser et al. 2016 NeuroImage 142:337-350), this study examined whether these abnormalities also characterize individuals at clinical high risk for MDD. We systematically explored the impact of family risk status and personal history of depression and anxiety on three distinct stages of emotional processing comprising the late positive potential (LPP). ERPs (72 channels) were recorded from 74 high and 53 low risk individuals (age 13-59 years, 58 male) during a visual half-field paradigm using highly-controlled pictures of cosmetic surgery patients showing disordered (negative) or healed (neutral) facial areas before or after treatment. Reference-free current source density (CSD) transformations of ERP waveforms were quantified by temporal principal components analysis (tPCA). Component scores of prominent CSD-tPCA factors sensitive to emotional content were analyzed via permutation tests and repeated measures ANOVA for mixed factorial designs with unstructured covariance matrix, including gender, age and clinical covariates. Factor-based distributed inverse solutions provided descriptive estimates of emotional brain activations at group level corresponding to hierarchical activations along ventral visual processing stream. Risk status affected emotional responsivity (increased positivity to negative-than-neutral stimuli) overlapping early N2 sink (peak latency 212 ms), P3 source (385 ms), and a late centroparietal source (630 ms). High risk individuals had reduced right-greater-than-left emotional lateralization involving occipitotemporal cortex (N2 sink) and bilaterally reduced emotional effects involving posterior cingulate (P3 source) and inferior temporal cortex (630 ms) when compared to those at low risk. While the early emotional effects were enhanced for left hemifield (right hemisphere) presentations, hemifield modulations did not differ between risk groups, suggesting top-down rather than bottom-up effects of risk. Groups did not differ in their stimulus valence or arousal ratings. Similar effects were seen for individuals with a lifetime history of depression or anxiety disorder in comparison to those without. However, there was no evidence that risk status and history of MDD or anxiety disorder interacted in their impact on emotional responsivity, suggesting largely independent attenuation of attentional resource allocation to enhance perceptual processing of motivationally salient stimuli. These findings further suggest that a deficit in motivated attention preceding conscious awareness may be a marker of risk for depression.

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…

Critical Success Factors (CSFs) for Implementation of Enterprise Resource Planning (ERP) Systems in Various Industries, Including Institutions of Higher Education (IHEs)

ERIC Educational Resources Information Center

Debrosse-Bruno, Marie Michael

2017-01-01

Enterprise Resource Planning (ERP) systems present a management problem for various industries including institutions of higher education (IHEs) because they are costly to acquire, challenging to implement, and often fail to meet anticipated expectations. ERP systems are highly complex due to the nature of the operations they support. This…

Technical-Oriented Enterprise Resource Planning (ERP) Body of Knowledge for Information Systems Programs: Content and Implementation

ERIC Educational Resources Information Center

Boyle, Todd A.

2007-01-01

In this article, the author proposes a body of knowledge that the educators can use to incorporate the technical aspects of enterprise resource planning (ERP) into an information systems (IS) program, encapsulated as the ERP technical knowledge framework. To illustrate the application of this framework, the author discusses a course sequence that…

75 FR 35027 - Notice of Public Information Collection Approved By the Office of Management and Budget

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-21

... must file an informal request for any increase in the station's FM Digital ERP). (2) Licensees to... Digital ERP beyond 6 dB. (3) Licensees submitting such a request must use a simplified method set forth in the Order to determine the proponent station's maximum permissible FM Digital ERP. (4) In situations...

47 CFR 73.213 - Grandfathered short-spaced stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... application for authority to operate a Class A station with no more than 3000 watts ERP and 100 meters antenna HAAT (or equivalent lower ERP and higher antenna HAAT based on a class contour distance of 24 km) must... application for authority to operate a Class A station with more than 3000 watts ERP (up to a maximum of 5800...

47 CFR 73.213 - Grandfathered short-spaced stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... application for authority to operate a Class A station with no more than 3000 watts ERP and 100 meters antenna HAAT (or equivalent lower ERP and higher antenna HAAT based on a class contour distance of 24 km) must... application for authority to operate a Class A station with more than 3000 watts ERP (up to a maximum of 5800...

47 CFR 22.567 - Technical channel assignment criteria.

Code of Federal Regulations, 2011 CFR

2011-10-01

... meters p is the radial ERP in Watts (1) Whenever the actual HAAT is less than 30 meters (98 feet), 30... must not be less than 27 dB less than the maximum ERP in any direction, or 0.1 Watt, whichever is more... contour using the formula in paragraph (c) of this section with actual HAAT and ERP data for the inter...

47 CFR 90.542 - Broadband transmitting power limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the 763-768 MHz band with an emission bandwidth of 1 MHz or less must not exceed an ERP of 1000 watts... if power levels are reduced below 1000 watts ERP in accordance with Table 1 of this section. (2... ERP of 2000 watts and an antenna height of 305 m HAAT, except that antenna heights greater than 305 m...

47 CFR 22.537 - Technical channel assignment criteria.

Code of Federal Regulations, 2011 CFR

2011-10-01

... distance in kilometers h is the radial antenna HAAT in meters p is the radial ERP in Watts (1) Whenever the...) The value used for p in the above formula must not be less than 27 dB less than the maximum ERP in any... HAAT and ERP data for the inter-station radial and additional radials above and below the inter-station...

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…

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…

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.

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.

High density event-related potential data acquisition in cognitive neuroscience.

PubMed

Slotnick, Scott D

2010-04-16

Functional magnetic resonance imaging (fMRI) is currently the standard method of evaluating brain function in the field of Cognitive Neuroscience, in part because fMRI data acquisition and analysis techniques are readily available. Because fMRI has excellent spatial resolution but poor temporal resolution, this method can only be used to identify the spatial location of brain activity associated with a given cognitive process (and reveals virtually nothing about the time course of brain activity). By contrast, event-related potential (ERP) recording, a method that is used much less frequently than fMRI, has excellent temporal resolution and thus can track rapid temporal modulations in neural activity. Unfortunately, ERPs are under utilized in Cognitive Neuroscience because data acquisition techniques are not readily available and low density ERP recording has poor spatial resolution. In an effort to foster the increased use of ERPs in Cognitive Neuroscience, the present article details key techniques involved in high density ERP data acquisition. Critically, high density ERPs offer the promise of excellent temporal resolution and good spatial resolution (or excellent spatial resolution if coupled with fMRI), which is necessary to capture the spatial-temporal dynamics of human brain function.

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.

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.

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.

Worklife expectancy in a cohort of Danish employees aged 55-65 years - comparing a multi-state Cox proportional hazard approach with conventional multi-state life tables.

PubMed

Pedersen, Jacob; Bjorner, Jakob Bue

2017-11-15

Work life expectancy (WLE) expresses the expected time a person will remain in the labor market until he or she retires. This paper compares a life table approach to estimating WLE to an approach based on multi-state proportional hazards models. The two methods are used to estimate WLE in Danish members and non-members of an early retirement pensioning (ERP) scheme according to levels of health. In 2008, data on self-rated health (SRH) was collected from 5212 employees 55-65 years of age. Data on previous and subsequent long-term sickness absence, unemployment, returning to work, and disability pension was collected from national registers. WLE was estimated from multi-state life tables and through multi-state models. Results from the multi-state model approach agreed with the life table approach but provided narrower confidence intervals for small groups. The shortest WLE was seen for employees with poor SRH and ERP membership while the longest WLE was seen for those with good SRH and no ERP membership. Employees aged 55-56 years with poor SRH but no ERP membership had shorter WLE than employees with good SRH and ERP membership. Relative WLE reversed for the two groups after age 57. At age 55, employees with poor SRH could be expected to spend approximately 12 months on long-term sick leave and 9-10 months unemployed before they retired - regardless of ERP membership. ERP members with poor SRH could be expected to spend 4.6 years working, while non-members could be expected to spend 7.1 years working. WLE estimated through multi-state models provided an effective way to summarize complex data on labor market affiliation. WLE differed noticeably between members and non-members of the ERP scheme. It has been hypothesized that while ERP membership would prompt some employees to retire earlier than they would have done otherwise, this effect would be partly offset by reduced time spent on long-term sick leave or unemployment. Our data showed no indication of such an effect, but this could be due to residual confounding and self-selection of people with poor health into the ERP scheme.

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.

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.

Interactions of Cd and Cu in anaerobic estuarine sediments. 1: Partitioning in geochemical fractions of sediments

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

Rule, J.H.; Alden, R.W. III

1996-04-01

Partitioning of Cd and Cu between geochemical fractions of an anaerobic estuarine sediment was determined after equilibrating fine-sandy sediment with different combinations of added Cd (0, 2.5, 5 mg/kg) and Cu(0, 12.5, 25 mg/kg). Sediments were placed in aquaria with 20 ppt seawater where bioassay test organisms were exposed for 14 d. At the start and conclusion of the experimental period, sediments were sequentially extracted to determine the elemental content of the exchangeable (EP), easily reducible (ERP), organic- sulfide (OSP), moderately reducible (MRP), and acid extractable (AEP) phases. Partitioning of the metals in both the native and treated sediments was,more » for Cd: OSP {much_gt} ERP > AEP > EP (MRP was below detection) and for Cu: OSP {much_gt} AEP > ERP > MRP > EP. Cadmium extracted in all phases and Cu in the EP, RP, and OSP were proportional to the respective treatments. The EP-Cd, ERP-Cd, and OSP-Cd were affected by the Cu treatment and significant interactions occurred between Cd and Cu for the EP-Cd, ERP-Cd, OSP-Cd, EP-Cu, and ERP-Cu. Increasing levels of applied Cd and Cu resulted in greater amounts of EP-Cd and ERP-Cd, fractions that are the most bioavailable and the most readily available for desorption into the water column. A significant conclusion is that the input of nontoxic metals may affect the geochemical phase distribution, potential bioavailability, and toxicity of native sediment metals.« less

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.

Alu expression in human cell lines and their retrotranspositional potential.

PubMed

Oler, Andrew J; Traina-Dorge, Stephen; Derbes, Rebecca S; Canella, Donatella; Cairns, Brad R; Roy-Engel, Astrid M

2012-06-20

The vast majority of the 1.1 million Alu elements are retrotranspositionally inactive, where only a few loci referred to as 'source elements' can generate new Alu insertions. The first step in identifying the active Alu sources is to determine the loci transcribed by RNA polymerase III (pol III). Previous genome-wide analyses from normal and transformed cell lines identified multiple Alu loci occupied by pol III factors, making them candidate source elements. Analysis of the data from these genome-wide studies determined that the majority of pol III-bound Alus belonged to the older subfamilies Alu S and Alu J, which varied between cell lines from 62.5% to 98.7% of the identified loci. The pol III-bound Alus were further scored for estimated retrotransposition potential (ERP) based on the absence or presence of selected sequence features associated with Alu retrotransposition capability. Our analyses indicate that most of the pol III-bound Alu loci candidates identified lack the sequence characteristics important for retrotransposition. These data suggest that Alu expression likely varies by cell type, growth conditions and transformation state. This variation could extend to where the same cell lines in different laboratories present different Alu expression patterns. The vast majority of Alu loci potentially transcribed by RNA pol III lack important sequence features for retrotransposition and the majority of potentially active Alu loci in the genome (scored high ERP) belong to young Alu subfamilies. Our observations suggest that in an in vivo scenario, the contribution of Alu activity on somatic genetic damage may significantly vary between individuals and tissues.

Positive and negative symptom scores are correlated with activation in different brain regions during facial emotion perception in schizophrenia patients: a voxel-based sLORETA source activity study.

PubMed

Kim, Do-Won; Kim, Han-Sung; Lee, Seung-Hwan; Im, Chang-Hwan

2013-12-01

Schizophrenia is one of the most devastating of all mental illnesses, and has dimensional characteristics that include both positive and negative symptoms. One problem reported in schizophrenia patients is that they tend to show deficits in face emotion processing, on which negative symptoms are thought to have stronger influence. In this study, four event-related potential (ERP) components (P100, N170, N250, and P300) and their source activities were analyzed using EEG data acquired from 23 schizophrenia patients while they were presented with facial emotion picture stimuli. Correlations between positive and negative syndrome scale (PANSS) scores and source activations during facial emotion processing were calculated to identify the brain areas affected by symptom scores. Our analysis demonstrates that PANSS positive scores are negatively correlated with major areas of the left temporal lobule for early ERP components (P100, N170) and with the right middle frontal lobule for a later component (N250), which indicates that positive symptoms affect both early face processing and facial emotion processing. On the other hand, PANSS negative scores are negatively correlated with several clustered regions, including the left fusiform gyrus (at P100), most of which are not overlapped with regions showing correlations with PANSS positive scores. Our results suggest that positive and negative symptoms affect independent brain regions during facial emotion processing, which may help to explain the heterogeneous characteristics of schizophrenia. © 2013 Elsevier B.V. All rights reserved.

Modeling the effects of changes in New Source Review on national SO{sub 2} and NOx emissions from electricity-generating units

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

David A. Evans; Benjamin F. Hobbs; Craig Oren

2007-03-15

The Clean Air Act establishes New Source Review (NSR) programs that apply to the construction or modification of major stationary emissions sources. In 2002 and 2003, the U.S. Environmental Protection Agency revised its rules to narrow the applicability of NSR to facility renovations. Congress then mandated a National Research Council study of the effects of the rules. An electricity-sector model - the Integrated Planning Model (IPM) - was used to explore the possible effects of the equipment replacement provision (ERP), the principal NSR change that was to affect the power-generation industry. The studies focused in particular on coal-fired electricity generatingmore » units, EGUs, for two reasons. First, coal-fired EGUs are important contributors of these pollutants, accounting for approximately 70 and 20% of nations SO{sub 2} and NOx emissions in 2004, respectively. Second, the shares of total capacity of large coal-fired EGUs that lack flue-gas desulfurization to control SO{sub 2} and selective catalytic reduction to reduce NOx emissions are 62 and 63% respectively. Although the analysis cannot predict effects on local emissions, assuming that the Clean Air Interstate Rule (CAIR) is implemented, we find that stringent enforcement of the previous NSR rules would likely lead to no or limited decreases in national emissions compared to policies such as ERP. Our results indicate that tighter emissions caps could achieve further decreases in national emissions more cost-effectively than NSR programs. 15 refs., 3 figs., 1 tab.« less

The effect of late posterior negativity in retrieving the color of Chinese characters.

PubMed

Nie, Aiqing; Guo, Chunyan; Liang, Junying; Shen, Mowei

2013-02-08

Previous event-related potentials (ERPs) research has suggested that the retrieval tasks for many sources of items were operated in the frontal regions, but Cycowicz et al. [2-4,6] recorded the late posterior negativity (LPN), a component over the posterior cortex, in retrieving the associative color sources of pictures. To examine whether the LPN could also be observed in retrieving both the associative and the organizational color sources of verbal stimuli, two experiments were designed by using Chinese nouns as stimuli. Both experiments revealed significant LPN that was related to the tasks of color source retrieval. These findings demonstrate that the association between LPN and search for and/or retrieval/evaluation of the colors of objects is fairly strong, and this association is insensitive to both the attributes of stimulus materials and those of the color sources. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

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

47 CFR 101.1333 - Interference protection criteria.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Maximum EIRP Watts dBW Maximum ERP 1 Watts dBW Master 941.0-941.5 1000 30 600 27.8 Fixed Remote and Master 932.0-932.5 50 17 30 14.8 1 Where ERP = EIRP/1.64.> (ii) Maximum antenna height above average terrain... Reduction Table Antenna height above average terrain (meters) EIRP Watts dBW ERP Watts dBW Above 305 200 23...

47 CFR 90.267 - Assignment and use of frequencies in the 450-470 MHz band for low power use.

Code of Federal Regulations, 2011 CFR

2011-10-01

... operation determine whether a station is within an “80 km circle.” (i) The maximum ERP for low power... ERP for low power operation on these frequencies is as follows: Operation Low side of frequency pair.... (2) Operation on these frequencies is limited to 6 watts ERP for base, mobile or operational fixed...

Infant ERPs Separate Children at Risk of Dyslexia Who Become Good Readers from Those Who Become Poor Readers

ERIC Educational Resources Information Center

Zuijen, Titia L.; Plakas, Anna; Maassen, Ben A. M.; Maurits, Natasha M.; van der Leij, Aryan

2013-01-01

Dyslexia is heritable and associated with phonological processing deficits that can be reflected in the event-related potentials (ERPs). Here, we recorded ERPs from 2-month-old infants at risk of dyslexia and from a control group to investigate whether their auditory system processes /bAk/ and /dAk/ changes differently. The speech sounds were…

SALT spectroscopic classification of SN 2017erp as a type-Ia supernova well before maximum light

NASA Astrophysics Data System (ADS)

Jha, S. W.; Camacho, Y.; Dettman, K.; Pan, Y.-C.; Foley, R. J.; Rest, A.; Scolnic, D.; Skelton, R.

2017-06-01

We obtained SALT (+RSS) spectroscopy of SN 2017erp (discovered by K. Itagaki) on 2017 Jun 13.9 UT, covering the wavelength range 350-940 nm. Cross-correlation of the supernova spectrum with a template library using SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows SN 2017erp is a type-Ia supernova before maximum light.

Total Cost of Ownership, System Acceptance and Perceived Success of Enterprise Resource Planning Software: Simulating a Dynamic Feedback Perspective of ERP in the Higher Education Environment

ERIC Educational Resources Information Center

Fryling, Meg

2010-01-01

Enterprise Research Planning (ERP) software is advertised as the product that will "run the enterprise", improving data access and accuracy as well as enhancing business process efficiency. Unfortunately, organizations often make implementation decisions with little consideration for the maintenance phase of an ERP, resulting in significant…

Gap detection measured with electrically evoked auditory event-related potentials and speech-perception abilities in children with auditory neuropathy spectrum disorder.

PubMed

He, Shuman; Grose, John H; Teagle, Holly F B; Woodard, Jennifer; Park, Lisa R; Hatch, Debora R; Buchman, Craig A

2013-01-01

This study aimed (1) to investigate the feasibility of recording the electrically evoked auditory event-related potential (eERP), including the onset P1-N1-P2 complex and the electrically evoked auditory change complex (EACC) in response to temporal gaps, in children with auditory neuropathy spectrum disorder (ANSD); and (2) to evaluate the relationship between these measures and speech-perception abilities in these subjects. Fifteen ANSD children who are Cochlear Nucleus device users participated in this study. For each subject, the speech-processor microphone was bypassed and the eERPs were elicited by direct stimulation of one mid-array electrode (electrode 12). The stimulus was a train of biphasic current pulses 800 msec in duration. Two basic stimulation conditions were used to elicit the eERP. In the no-gap condition, the entire pulse train was delivered uninterrupted to electrode 12, and the onset P1-N1-P2 complex was measured relative to the stimulus onset. In the gapped condition, the stimulus consisted of two pulse train bursts, each being 400 msec in duration, presented sequentially on the same electrode and separated by one of five gaps (i.e., 5, 10, 20, 50, and 100 msec). Open-set speech-perception ability of these subjects with ANSD was assessed using the phonetically balanced kindergarten (PBK) word lists presented at 60 dB SPL, using monitored live voice in a sound booth. The eERPs were recorded from all subjects with ANSD who participated in this study. There were no significant differences in test-retest reliability, root mean square amplitude or P1 latency for the onset P1-N1-P2 complex between subjects with good (>70% correct on PBK words) and poorer speech-perception performance. In general, the EACC showed less mature morphological characteristics than the onset P1-N1-P2 response recorded from the same subject. There was a robust correlation between the PBK word scores and the EACC thresholds for gap detection. Subjects with poorer speech-perception performance showed larger EACC thresholds in this study. These results demonstrate the feasibility of recording eERPs from implanted children with ANSD, using direct electrical stimulation. Temporal-processing deficits, as demonstrated by large EACC thresholds for gap detection, might account in part for the poor speech-perception performances observed in a subgroup of implanted subjects with ANSD. This finding suggests that the EACC elicited by changes in temporal continuity (i.e., gap) holds promise as a predictor of speech-perception ability among implanted children with ANSD.

Dysfunctional frontal lobe activity during inhibitory tasks in individuals with childhood trauma: An event-related potential study.

PubMed

Kim, Sungkean; Kim, Ji Sun; Jin, Min Jin; Im, Chang-Hwan; Lee, Seung-Hwan

2018-01-01

Individuals who experience childhood trauma are vulnerable to various psychological and behavioral problems throughout their lifetime. This study aimed to investigate whether individuals with childhood trauma show altered frontal lobe activity during response inhibition tasks. In total, 157 healthy individuals were recruited and instructed to perform a Go/Nogo task during electroencephalography recording. Source activities of N2 and P3 of Nogo event-related potentials (ERP) were analyzed. The Childhood Trauma Questionnaire (CTQ) and Barratt Impulsivity Scale (BIS) were applied. Individuals were divided into three groups based on their total CTQ score: low CTQ, middle CTQ, and high CTQ groups. The high CTQ group exhibited significantly higher BIS scores than the low CTQ group. P3 amplitudes of the differences between Nogo and Go ERP waves exhibited higher mean values in the low CTQ than the high CTQ group, with trending effects. In Nogo-P3, the source activities of the right anterior cingulate cortex, bilateral medial frontal cortex (MFC), bilateral superior frontal gyrus (SFG), and right precentral gyrus were significantly lower in the high CTQ than the low CTQ group. Motor impulsivity showed a significant negative correlation with activities of the bilateral MFC and SFG in Nogo-P3 conditions. Our study revealed that individuals with childhood trauma have inhibitory failure and frontal lobe dysfunction in regions related to Nogo-P3.

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.