Event-related potentials (ERPs) have been used for decades to study perception, cognition, emotion, neurological and psychiatric disorders, and lifespan development. ERPs consist of multiple components and reflect a specific neurocognitive process.
Finally, we checked whether the same ERP component similar to N250 could be detected after the VPP components. Since previous studies have suggested that N170 and VPP components could be generated by the same neural modules, we checked whether we could find the same ERP component as N250 after VPP or not. We measured frontal activity during 250-350 ms after the stimulus onset, at FP1 and FP2 electrode sites where we measured VPP, and we called it post-VPP activity (see Methods section). Post-VPP activity, in contrast to N170, VPP, and N250 brain potentials, was not systematically affected by stimulus visibility and the only prominent difference was among ERP trials in which SOA = 500 ms, relative to the rest of the trials ( Figures 3b and 8). During both face detection and leaf detection tasks, application of a two-factor repeated measures ANOVA (stimulus category (face vs. leaf vs. other objects) × SOA (10 vs. 20 vs. 30 vs. 500 ms)) yielded a significant effects of stimulus visibility ( F , ...
The present study examined the electrophysiological correlates of intentional forgetting using the item-method directed forgetting paradigm. Participants (N=23) studied a series of words each followed by either a "remember" cue (TBR) or a "forget" cue (TBF) and then undertook an old/new recognition memory test for which they were requested to endorse studied items regardless of original remember/forget status. Event-related potentials time locked to the cues were examined as a function of subsequent recognition-memory accuracy. Results showed that TBR and TBF cues elicited Dm or subsequent memory effects that differed in scalp distribution and polarity, suggesting activation of fundamentally different encoding operations for the respective sets of items. Additionally, analyses that examined the processes underlying successful implementations of intentions to forget (i.e., TBF-miss vs. TBR-miss) and intentions to remember (i.e., TBR-hit vs. TBF-hit) revealed that in case of unwanted information a ...
It was definitely a very negative wave of spiritual energy around me. I can tell when it happens now. I know that it was trying to make me do things wrong. I am not controlled by spirits at all. I cannot be controlled into doing things anymore. But the wave was still there and it…
Links between attention and emotion were investigated by obtaining electrophysiological measures of attentional selectivity together with behavioral measures of affective evaluation. Participants were asked to rate faces that had just been presented as targets or distractors in a visual search task. Distractors were rated as less trustworthy than targets. To study the association between the efficiency of selective attention during visual search and subsequent emotional responses, the N2pc component was quantified as a function of evaluative judgments. Evaluation of distractor faces (but not target faces) covaried with selective attention. On trials where distractors were later judged negatively, the N2pc emerged earlier, demonstrating that attention was strongly biased toward target events, and distractors were effectively inhibited. When previous distractors were judged positively, the N2pc was delayed, indicating unfocused attention to the target and less distractor suppression. Variations in
In this study, we used a traditional auditory oddball paradigm, in which participants were required to press a button for the infrequent target stimulus while ignoring the frequent non-target standard stimulus while ignoring the frequent non-target standard stimulus, and focused on P3 component, which is a generic name for a variety of relatively late positive components with a centro-parietal or centro-frontal midline distribution [17, 18]. In addition, we will also investigate the N2, a frontal-central distributed negativity that reflects the stimulus evaluation response including action monitoring, the early target-selection and response preparation [19]. If there were gender effects on cognitive function in patients, it should be reflected by a modulation of the N2 and/or P3 components.. The present study found the P3 component was larger for female than for male participants, for both the patient and control groups. Compared with the control group, there was a decrease in the amplitude of ...
Visual object identification is modulated by perceptual experience. In a cross-cultural ERP study we investigated whether cultural expertise determines how buildings that vary in their ranking between high and low according to the Western architectural decorum are perceived. Two groups of German and Chinese participants performed an object classification task in which high- and low-ranking Western buildings had to be discriminated from everyday life objects. ERP results indicate that an early stage of visual object identification (i.e., object model selection) is facilitated for high-ranking buildings for the German participants, only. At a later stage of object identification, in which object knowledge is complemented by information from semantic and episodic long-term memory, no ERP evidence for cultural differences was obtained. These results suggest that the identification of architectural ranking is modulated by culturally specific expertise with Western-style architecture already at an ...
We used event-related potentials (ERPs) to explore the influence of manipulating facial expression on error monitoring in individuals. The participants were 11 undergraduate students who had been diagnosed with minor depression (MinD). We recorded error-related negativity (ERN) as the participants performed a modified flanker task in 3 conditions: Duchenne smile, standard smile, and no smile. Behavioral data results showed that, in both the Duchenne smile and standard smile conditions, error rates were significantly lower than in the no-smile condition. The ERP analysis results indicated that, compared to the no-smile condition, both Duchenne and standard smiling facial expressions decreased ERN amplitude, and ERN amplitudes were smallest for those in the Duchenne smile condition. Our findings suggested that even brief smile manipulation may improve long-term negative mood states of people with MinD ...
Two experiments examined phonological priming effects on reaction times, error rates, and event-related brain potential (ERP) measures in an auditory lexical decision task. In Experiment 1 related prime-target pairs rhymed, and in Experiment 2 they alliterated (i.e., shared the consonantal onset and vowel). Event-related potentials were recorded in a delayed response task. Reaction times and error rates were obtained both for the delayed and an immediate response task. The behavioral data of Experiment 1 provided evidence for phonological facilitation of word, but not of nonword decisions. The brain potentials were more negative to unrelated than to rhyming word-word pairs between 450 and 700 msec after target onset. This negative enhancement was not present for word-nonword pairs. Thus, the ERP results match the behavioral data. The behavioral data of Experiment 2 provided no evidence for phonological Facilitation. However, between 250 and 450 msec after target onset, i.e., considerably earlier ...
We used high-density event-related potentials (ERP) in a modified flanker paradigm to study the role of anticipated action consequences in action planning and the role of anticipation in the perception of action consequences. Prior to the experiment, participants were trained to classify target letters in a four-alternative forced-choice task; another letter was presented as an effect following each response. After participants had thus acquired the response-effect contingencies, in the experiment effect letters were presented as flankers to target letters. Effect-compatible flankers were letters that were learned as effects of the correct response to the target; effect-incompatible ones were learned as effects of other responses; neutral flankers were never presented as action effects. To help distinguish early and late effects of flankers on target processing, flankers were presented either simultaneously with the target or after a delay. We found that effect-incompatible flankers resulted in ...
Electrophysiological correlates of common-onset visual masking. In common-onset visual masking (COVM) the target and the mask come into view simultaneously. Masking occurs when the mask remains on the screen for longer after deletion of the target. Enns and Di Lollo [Enns, J. T., & Di Lollo, V. (2000). Whats new in visual masking? Trends in Cognitive Sciences, 4(9), 345-352] have argued that this type of masking can be explained by re-entrant visual processing. In the present studies we used high-density event-related brain potentials (HD-ERP) to obtain neural evidence for re-entrant processing in COVM. In two experiments the participants task was to indicate the presence or absence of a vertical bar situated at the lower part of a ring highlighted by the mask. The only difference between the experiments was the duration of the target: 13 and 40 ms for the first and second experiment respectively. Behavioral results were consistent between experiments: COVM was stronger as a joint function of ...
Motor learning can be monitored by observing the development of neural correlates of error processing. Among these neural correlates, the error- and feedback-related negativity (Ne/ERN and FRN) represent error processing mechanisms. While the Ne/ERN is more related to error prediction, the FRN is found after an error is manifested. The questions the current study strives to answer are: What information is needed by the system to make error predictions and how is this represented by the Ne/ERN and FRN in a complex motor task? We reduced the information and increased the difficulty level for the prediction in a semivirtual throwing task and found no Ne/ERN but a large FRN when the action result was finally observed (hitting or missing a target). We assume that uncertainty for error prediction was too high (either due to insufficient information or due to lacking prerequisites for prediction), such that error processing had to be mainly based on feedback. The finding is in line with the ...
TY - JOUR. T1 - Neural mechanisms of global and local processing. T2 - A combined PET and ERP study. AU - Heinze, H. J.. AU - Hinrichs, H.. AU - Scholz, M.. AU - Burchert, W.. AU - Mangun, George R. PY - 1998. Y1 - 1998. N2 - The neural mechanisms of hierarchical stimulus processing were investigated using a combined event-related potentials (ERPs) and positron emission tomography (PET) approach. Healthy subjects were tested under two conditions that involved selective or divided attention between local and global levels of hierarchical letter stimuli in order to determine whether and where hemispheric differences might exist in the processing of local versus global information. When attention was divided between global and local levels, the N2 component of the ERPs (260- to 360-msec latency) elicited by the target stimuli showed asymmetries in amplitude over the two hemispheres. The N2 to local targets was larger over the left hemisphere, but the N2 to global targets tended to be slightly ...
Studies of electrophysiological indices of performance monitoring, such as the error-related negativity (ERN), posterror positivity (Pe), and N2 components of the event-related potential (ERP),...
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Author: Hagoort, Peter; Genre: Talk; Title: Order out of chaos: An explicit account of ERP effects on the interface of lexicon, grammar and semantics
By themselves, there are no specific tests that can determine if a person has MS or is likely to have it in the future. Current diagnosis of definite MS involves both clinical (history and neurological exam) and paraclinical (MRI, Spinal Tap, Evoked potentials) evidence.. The diagnosis evolves from a discussion between the patient and the physician. A careful medical history is taken; symptoms and signs are assessed. Other ailments are ruled out. The diagnosis is highly dependent on the accuracy of the patients medical history and the physicians skill in eliciting and evaluating this information. The diagnosis is sometimes obvious and sometimes very difficult. Even in the hands of experts, the diagnosis is correct only 90 - 95 percent of the time.. The physician will ask about past surgeries, illnesses, allergies, any family neurological disorders including MS, geographic locations where you have lived, if adversely affected by heat, medications taken, history of substance abuse (alcohol, ...
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We carry out a systematic qualitative analysis of the two quadratic schemes of generalized oscillators recently proposed by Quesne [J. Math. Phys. 56, 012903 (2015)]. By performing a local analysis of the governing potentials, we demonstrate that while the first potential admits a pair of equilibrium points one of which is typically a center for both signs of the coupling strength λ, the other points to a centre for λ , 0 but a saddle λ , 0. On the other hand, the second potential reveals only a center for both the signs of λ from a linear stability analysis. We carry out our study by extending Quesnes scheme to include the effects of a linear dissipative term. An important outcome is that we run into a remarkable transition to chaos in the presence of a periodic force term fcosωt. ...
Women tend to respond to emotional stimuli differently from men. This study aimed at investigating whether neural responses to perceptually
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Research on familiar face recognition has largely focused on the neural correlates of recognizing a beloved partner or family member. However, no research has explored the effect of marriage style on the recognition of a beloved partners face, especially in matriarchal societies. Here, we examined the time course of event-related potentials (ERP) in response to the face of a beloved partner, sibling, or unknown person in a sample of individuals from the matriarchal Mosuo tribe. Two groups were assessed: intermarriage and walking marriage groups (i.e., couples in a committed relationship who do not cohabitate during the daytime). In agreement with previous reports, ERP results revealed more positive VPP, N250, and P300 waveforms for beloved faces than sibling faces in both groups. Moreover, P300 was more positive for beloved partner versus sibling faces; however, this difference emerged at fronto-central sites for the walking marriage group and at posterior sites for the intermarriage group. Overall, we
Simultaneous recording of event-related electroencephalographic (EEG) and functional magnetic resonance imaging (fMRI) responses has the potential to provide information on how the human brain reacts to an external stimulus with unique spatial and temporal resolution. However, in most studies combining the two techniques, the acquisition of functional MR images has been interleaved with the recording of evoked potentials. In this study we investigated the feasibility of recording pain-related evoked potentials during continuous and simultaneous collection of blood oxygen level-dependent (BOLD) functional MR images at 3 T. Brain potentials were elicited by selective stimulation of cutaneous Adelta and C nociceptors using brief radiant laser pulses (laser-evoked potentials, LEPs). MR-induced artifacts on EEG data were removed using a novel algorithm. Latencies, amplitudes, and scalp distribution of LEPs recorded during fMRI were not significantly different from those recorded in a control session outside
Auditory novelty detection has been associated with different cognitive processes. Bekinschtein et al. (2009) developed an experimental paradigm to dissociate these processes, using local and global novelty, which were associated, respectively, with automatic versus strategic perceptual processing. They have mostly been studied using event-related potentials (ERPs), but local spiking activity as indexed by gamma (60-120 Hz) power and interactions between brain regions as indexed by modulations in beta-band (13-25 Hz) power and functional connectivity have not been explored. We thus recorded 9 epileptic patients with intracranial electrodes to compare the precise dynamics of the responses to local and global novelty. Local novelty triggered an early response observed as an intracranial mismatch negativity (MMN) contemporary with a strong power increase in the gamma band and an increase in connectivity in the beta band. Importantly, all these responses were strictly confined to the temporal ...
BACKGROUND:Individuals with schizophrenia have heterogeneous impairments of the auditory processing system that likely mediate differences in the cognitive gains induced by auditory training (AT). Mismatch negativity (MMN) is an event-related potential component reflecting auditory echoic memory, and its amplitude reduction in schizophrenia has been linked to cognitive deficits. Therefore, MMN may predict response to AT and identify individuals with schizophrenia who have the most to gain from AT. Furthermore, to the extent that AT strengthens auditory deviance processing, MMN may also serve as a readout of the underlying changes in the auditory system induced by AT. METHODS:Fifty-six individuals early in the course of a schizophrenia-spectrum illness (ESZ) were randomly assigned to 40 h of AT or Computer Games (CG). Cognitive assessments and EEG recordings during a multi-deviant MMN paradigm were obtained before and after AT and CG. Changes in these measures were compared between the treatment ...
The current study investigated the neurophysiological underpinnings of emotional maintenance in schizophrenia (SCZ) and whether aberrant neural responses predicted deficits in affective decision making and real-world motivated behavior. Event-related potentials (ERPs) were recorded from 27 SCZ outpatients and 23 healthy controls (CN) during an emotional maintenance task in which participants were presented an initial image for 3 seconds and then required to maintain a mental representation of the intensity that image over a delay period of varying lengths and determine whether the initial image was more or less intense than the second image. The Late Positive Potential (LPP) was used as a neurophysiological marker of emotional maintenance during the delay period. SCZ showed normal in-the-moment emotion experience to positive stimuli; however, SCZ rated negative and neutral pictures as more intense than CN. SCZ also displayed deficits in emotional maintenance accuracy. Furthermore, ERP data ...
Tinnitus related distress corresponds to different degrees of attention paid to the tinnitus. Shifting attention to a signal other than the tinnitus is therefore particularly difficult for patients wi
Sarica Y.; Karacan I., 1988: Electrophysiological correlates of sensory innervation of the vesico urethral junction and urethra in man
The reliability of cue-based conscious expectation improves with increasing predictive value of the cue. Here we report that expectation strengthens delta-band phase-entrainment to and speeds up the detection of relevant stimulus events. Our results further reveal that target events expected with high confidence are likely to 1) coincide with the negative-going phase of the frontocentral delta oscillations, 2) elicit short-latency and high-amplitude delta-peak (P300) ERP responses, and 3) are quickly detected consciously. Therefore, we suggest that the entrainment of cortical delta oscillations to expected stimulus onsets plays an important role in mediating the effects of anticipation on target detection in humans. Our study extends the recent finding that low-frequency oscillations entrain to rhythmic stimuli in macaques (Lakatos et al., 2008) to humans. Moreover, our results go beyond the previous understanding about passive phase-entrainment, providing evidence that phase concentration-and ...
We tested 14-month-olds and adults in an event-related potentials (ERPs) study in which pictures of familiar objects generated expectations about upcoming word forms. Expected word forms labelled the picture (word condition), while unexpected word forms mismatched by either a small deviation in word medial vowel height (mispronunciation condition) or a large deviation from the onset of the first speech segment (pseudoword condition). Both infants and adults showed sensitivity to both types of unexpected word form. Adults showed a chain of discrete effects: positivity over the N 1 wave, negativity over the P 2 wave (PMN effect) and negativity over the N 2 wave (N400 effect). Infants showed a similar pattern, including a robust effect similar to the adult P 2 effect. These observations were underpinned by a novel visualisation method which shows the dynamics of the ERP within bands of the scalp over time. The results demonstrate shared processing mechanisms across development, as even subtle
Schankin, A.; Wascher, E.: What do we and our brain see when we do not expect a stimulus? Results from a lateralized event-related potential study (N2PC). 46th Annual Meeting of the Society for Psychophysiological Research (SPR), Vancouver, BS, Canada (2006 ...
The optimal performance of an action depends to a great extend on the ability of a person to prepare in advance the appropriate kinetic and kinematic parameters at a specific point in time in order to meet the demands of a given situation and to foresee its consequences to the surrounding environment. In the research presented in this thesis, I employed high-density electroencephalography in order to study the neural processes underlying preparation for action. A typical way for studying preparation for action in neuroscience is to divide it in temporal preparation (when to respond) and event preparation (what response to make). In Chapter 2, we identified electrophysiological signs of implicit temporal preparation in a task where such preparation was not essential for the performance of the task. Electrophysiological traces of implicit timing were found in lateral premotor, parietal as well as occipital cortices. In Chapter 3, explicit temporal preparation was assessed by comparing anticipatory ...
Examples of current source density (CSD) waveforms (A) and CSD maps (B). EEG data (SEPs) shown in Fig. 2 were subjected to CSD transformation. Isolatency dotte
This is just a follow up on some threads that fat maybe a trigger to rosacea, in at least one forum member. Personally, I have never really heard this association, so am somewhat skeptical, though open to the possibility. The only potential evidence i know to this is that red meat has been linked to worsening rosacea, compared to fish or veggies. This however may not be due to the fat.... Clearly fat is important for our bodies to function normally, so it would not seem logical to totally
You may want to look into the LFP modelling work of Alain Destexhes lab: http://cns.iaf.cnrs-gif.fr/Main.html and Gaute Einevolls lab: http://compneuro.umb.no/ . They have both been producing some very interesting work on the origin and features of local field potentials. If you are using simplified point neuron models, it may be worth looking at Alberto Mazzonis recent papers on LFPs insimplified models: http://www.iit.it/en/component/profiles ... ile&id=385 ...
Figure 6. Spikes are embedded in unique synapsembles and spatially distributed LFP - The origin of extracellular fields and currents - EEG, ECoG, LFP and spikes
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I was excited to see that local field potentials were added! Unfortunately I was having trouble getting them to work, likely due to my own ignorance. I have the same code as in my previous post about plotRatePSD, where I create a network with the following populations ...
This book reviews a productive period of research aimed at connecting brain and mind through the use of scalp-recorded brain potentials to chart the temporal course of information processing in the human brain. The book serves as both as a summary of where we have been and as a pointer of the way ahead. Event-related potential (ERP) methodology has long been used in neuroscience to measure electrical activity in the brain. It has become clear, however, that it can be a powerful tool in studying and illuminating central psychological issues relating to attention, information, processing, dynamics, memory, and language. Linking this technology to newer imaging techniques such as positron emission tomography (PET) and functional magnetic resonance imaging (MRI), it becomes possible to build up a spatial and temporal picture of the brain during the performance of high-level skills. This book provides strong evidence that cognitive psychology can benefit from the use of brain electrical activity.
1. Wolf OT, Naumann E, Hellhammer DH, et al. Effects of dehydroepiandrosterone replacement in elderly men on event-related potentials, memory, and well-being. J Gerontol. 1998;53:M385-M390. 2. Wolf OT, Neumann O, Hellhammer DH, et al. Effects of a two-week physiological dehydroepiandrosterone substitution on cognitive performance and well-being in healthy elderly women and men. J Clin Endocrinol Metab. 1997;82:2363-2367. 3. Barnhart KT, Freeman E, Grisso JA, et al. The effect of dehydroepiandrosterone supplementation to symptomatic perimenopausal women on serum endocrine profiles, lipid parameters, and health-related quality of life. J Clin Endocrinol Metab. 1999;84:3896-3902. 4. Flynn MA, Weaver-Osterholtz D, Sharpe-Timms KL, et al. Dehydroepiandrosterone replacement in aging humans. J Clin Endocrinol Metab. 1999;84:1527-1533. 5. van Niekerk JK, Huppert FA, Herbert J. Salivary cortisol and DHEA: association with measures of cognition and well-being in normal older men, and effects of three ...
Evidence from visual probe detection tasks suggests that anxious individuals exhibit biased (enhanced) selective attention to threat stimuli, such as angry and fearful faces. Attentional bias to threatening stimuli has been characterized by (1) facilitated attention to stimuli (vigilance), (2) difficulty disengaging attention away from stimuli, or (3) attentional avoidance of stimuli. The current study used event-related potentials (ERP) and behavioural performance measures to examine the effects of attentional bias towards ecologically threatening stimuli (emotional faces) in 18 post-traumatic stress disorder (PTSD) patients and 18 healthy controls during a dot probe task. Behavioural measures of target detection and the amplitude and latency of early (P100, N100) and late (P200, P300) ERPs were assessed during presentation of face pair displays and target probes. Processing of threat-face pairs did not reveal evidence of attentional bias in PTSD patients. Perceptual (P100) and cognitive ...
Errors in speeded decision tasks are associated with characteristic patterns of brain activity. In the scalp-recorded EEG, error processing is reflected in two components, the error-related negativity (ERN) and the error positivity (Pe). These components have been widely studied, but debate remains regarding the precise aspects of error processing they reflect. The present study investigated the relation between the ERN and the Pe using a novel version of the flanker task to allow a comparison between errors reflecting different causes-response conflict versus stimulus masking. The conflict and mask conditions were matched for overall behavioural performance but differed in underlying response dynamics, as indexed by response time distributions and measures of lateralised motor activity. ERN amplitude varied in relation to these differing response dynamics, being significantly larger in the conflict condition compared to the mask condition. Furthermore, differences in response dynamics between
An engaging Q & A format is used to discuss how auditory evoked-related potentials can help understand the cognitive factors involved in word recognition. 12731 AudiologyOnline Article
TY - JOUR. T1 - Observations on field potentials at their point of generation. AU - Hentall, Ian D.. PY - 1994/11. Y1 - 1994/11. N2 - A technique for evoking then recording field potentials through one extracellular electrode was studied in the dentate gyrus of pentobarbital-anesthetized rats. In the molecular layer (the location of granule cell dendrites), a -5 μA pulse (0.4 ms, 0.2 Hz) consistently elicited a focal response the major component of which was a negative-going wave of about 1 ms latency, 10 ms duration, and -0.8 to -1.5 mV amplitude. This wave resembled, and could partially occlude, field excitatory post-synaptic potentials (EPSPs) elicited electrically from the perforant path. It fatigued during high-frequency stimulation and is suggested to consist largely of granule-cell EPSPs produced by directly activated, perforant-path terminals. Focal and perforant-path tetanic stimulation led to stable potentiation of the focal negative phase. Stimulus-response curves for the negative ...
Evaluating the familiarity of faces is critical for social animals as it is the basis of individual recognition. In the present study, we examined how face familiarity is reflected in neural activities in our closest living relative, the chimpanzee. Skin-surface event-related brain potentials (ERPs) were measured while a fully awake chimpanzee observed photographs of familiar and unfamiliar chimpanzee faces (Experiment 1) and human faces (Experiment 2). The ERPs evoked by chimpanzee faces differentiated unfamiliar individuals from familiar ones around midline areas centered on vertex sites at approximately 200 ms after the stimulus onset. In addition, the ERP response to the image of the subjects own face did not significantly diverge from those evoked by familiar chimpanzees, suggesting that the subjects brain at a minimum remembered the image of her own face. The ERPs evoked by human faces were not influenced by the familiarity of target individuals. These results indicate that chimpanzee neural
P300 thresholds were consistently higher than psychophysical thresholds. This is not surprising. The generation of the P300 relies on the percept that is generated immediately after the onset of the stimulus. Psychophysical thresholds were obtained with standard procedures that allow for prolonged inspection of the stimulus. At least for Landolt C stimuli, it is known that such a difference can have a sizable effect on the test outcome.51 Furthermore, the present oddball paradigm was based on the Landolt C gap or the grating stripes being present in infrequent trials and being absent in frequent trials, as opposed to the situation in a psychophysical acuity test in which the gap is always present, but the stimulus orientation has to be determined. Resembling a detection task, the P300-based acuity may thus be reduced. It should be noted that we took a very different approach to estimating thresholds from ERP amplitudes than that taken by, for instance, Norcia et al.52 and Bach et al.15 in ...
Current source density analysis (CSD) is a class of methods of analysis of extracellular electric potentials recorded at multiple sites leading to estimates of current sources generating the measured potentials. CSD Montage in WinEEG is based on spherical spline algorithm (Perrin et al., 1989) to compute scalp surface Laplacian or Current Source Density estimates for surface potentials (EEG/ERP). To create "CSD montage" you need to follow following steps:. ...
Brian F. ODonnell, Dean F. Salisbury, Margaret A. Niznikiewicz, Colleen A. Brenner and Jenifer L. Vohs.. in The Oxford Handbook of Event-Related Potential Components. December 2011; p ublished online September 2012 . Article. Subjects: Psychology; Cognitive Psychology; Cognitive Neuroscience. 18623 words. ...
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TY - JOUR. T1 - Reproducibility of p3. AU - Zamrini, Edward Y.. AU - Meador, Kimford J.. AU - Thompson, William O.. AU - Lee, Gregory P. PY - 1991/1/1. Y1 - 1991/1/1. N2 - The P3 event-related potential has been widely employed in both clinical and research investigations. In the present study, P3 latency and amplitude intersession reliability were evaluated in 4 sessions over an average of 33 days in 24 healthy adults using the P3 tonal oddball paradigm. Mean group latencies ranged from 302-305 ms and mean amplitudes ranged from 7.75-8.87 μV. No significant group differences were found across sessions for latency or amplitude. Intrasubject variability was large; the 95% confidence interval for the difference between the means of two combined sessions was ±20 ms for latency and ±4.63 μV for amplitude. The results suggest that P3 latency and amplitude are reliable and reproducible over weeks for groups, but have greater variability for individuals.. AB - The P3 event-related potential has ...