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Deception and the Systemic Problem of Substance Abuse
Published in Harold V. Hall, Joseph G. Poirier, Detecting Malingering and Deception, 2020
Harold V. Hall, Joseph G. Poirier
The ERP waveform voltage amplitudes are identified as being positive or negative and by degree of latency (i.e., time of wave peak post stimulus onset). For example, P300 would identify a positive peak that occurred 300 milliseconds post stimulus onset. For several decades, P300 activity has been known to be an (ERP) component related to decision-making behavior (Key et al., 2005; Polich, 1991, 1997). Parietal lobe electrodes are where P300 activity is most strongly evidenced and is attributed to attentional allocation.
Neurophysiological changes associated with dementia in Down syndrome
Published in Vee P. Prasher, Down Syndrome and Alzheimer’s Disease, 2018
Frank E. Visser, Satnam Kunar, Vee P. Prasher
The auditory evoked potential (AEP) (P3 or P300) response is recorded around 300 milliseconds after a stimulus of an infrequent but relevant tone has been presented in a series of frequent ‘ignored’ tones. The P300 or ‘P3b’ component is a scalp positivity that is typically maximal at centroparietal midline sites around 300 milliseconds after the stimulus.43 Although there is no consensus about the precise cognitive processes underlying the P3 component,44–46 it is clearly sensitive to attentional resource allocation and working memory load. Factors that influence the P300 size include subjective probability, stimulus saliency, attention and inter-stimulus interval, whereas the P300 is relatively independent of the sensory input characteristics.47,48 One view is that the P300 reflects the updating of working memory.45 Although the P300 latency is closely related to the complexity of the stimulus evaluation phase, the P300 amplitude is most sensitive to the subjective probability of the target’s occurrence, where decreased probability results in larger amplitudes.49
Gentle Introduction to Signal Processing and Classification for Single-Trial EEG Analysis
Published in Chang S. Nam, Anton Nijholt, Fabien Lotte, Brain–Computer Interfaces Handbook, 2018
A good starting point for discussing single-trial classification is the amplitude threshold criterion, which is a simple classification rule for a single quantity derived from measured data, which we will refer to as a univariate1feature. We will notice that this univariate setting is ideal for studying the basic concept of classification, which can be extended easily to multidimensional (multivariate) features and more complex classification rules. We here consider electroenchephalogram (EEG) data acquired in a so-called oddball experiment. In this experiment, six different visual stimuli were presented to the participant in random order at a presentation rate of 5 Hz. The participants were instructed to pay attention to one kind of stimulus (i.e., 16.66 %) and to mentally count the number of their occurrences. Attended stimuli (called targets or “oddballs”) elicit a so-called P300 component (Key et al. 2005) in the EEG, which is a positive voltage deflection observable at central EEG channels. Targets are thus characterized by larger amplitudes in these channels than the stimuli that were to be ignored (the nontargets). The P300 can be related to brain processes evaluating the relevance of the given stimulus for the task (see also Ref. Wenzel et al. 2017). Since it is locked to the time of the stimulus onset, the P300 belongs to the class of so-called event-related potentials (ERPs).
Presence of endolymphatic hydrops on listening difficulties in patients with normal hearing level
Published in Acta Oto-Laryngologica, 2023
Tadao Yoshida, Masumi Kobayashi, Satofumi Sugimoto, Yukari Fukunaga, Daisuke Hara, Shinji Naganawa, Michihiko Sone
Mismatch negativity and P300 are known as event-related potentials associated with hearing. Mismatch negativity is a negative potential detected at a latency of 100–200 ms after a sound stimulus [5]. P300 is a positive wave that is recognized at a latency of about 300 ms after a sound stimulus. Event-related potentials are considered to reflect higher-order functions and are used to assess the effects of treatments for psychological, physiological, psychiatric, and neurological disorders. Mismatch negativity is expected to be applied to the study of auditory memory, such as attention testing for infants who cannot understand tasks, and for the temporal integration of auditory information. P300 is considered useful as an objective method for evaluating attention function in people with attention deficit hyperactivity disorder in terms of temporal changes and treatment effects and as an objective method to evaluate APD. P300 is also expected to be a neurophysiological biomarker for the objective assessment of APD.
MEG reveals preference specific increases of sexual-image-evoked responses in paedophilic sexual offenders and healthy controls
Published in The World Journal of Biological Psychiatry, 2021
Marina Krylova, Inka Ristow, Vanessa Marr, Viola Borchardt, Meng Li, Joachim Witzel, Krasimira Drumkova, Joseph A. Harris, Norman Zacharias, Kolja Schiltz, Till Amelung, Klaus M. Beier, Tillmann H. C. Kruger, Jorge Ponseti, Boris Schiffer, Henrik Walter, Christian Kärgel, Martin Walter
The P300 is most commonly referred to in the context of attentional switch and information processing, more specifically in updating working memory and problem-solving (Dinteren et al. 2014). Typically, P300 is subdivided into the P3a and P3b component, with the P3a involved in early attention-related processes (‘novelty detection’) served by the frontal cortex and the hippocampus (Huster et al. 2010), and the P3b crucial for later attention-related processes and working memory, served by the temporal and parietal lobes, and cingulate cortex. In the P3a window, present sources of activity were observed in occipital, parietal and temporal areas as well as in orbitofrontal cortex in both HC and P + CSO. P + CSO exhibited increased amplitudes in response to child images in the P3a window in middle orbital and middle frontal gyrus (Supplementary Table 1). These effects could be interpreted in terms of dorsal and ventral stream of the visual pathways. Especially, the P + CSO show activation regarding ventral stream, which is associated with form recognition and object representation, with storage of long-term memory subsequent cognitive operations (Goodale and Milner 1992).
Role of visual P300 in cognitive assessment of subacute stroke patients: a longitudinal study
Published in International Journal of Neuroscience, 2020
Simona De Salvo, Viviana Lo Buono, Lilla Bonanno, Katia Micchia, Emanuele Cartella, Laura Romeo, Francesca Arcadi, Francesco Corallo, Fabrizia Caminiti, Alessia Bramanti, Roberto Giorgianni, Silvia Marino
The P300 (ERPs’s main wave) is generated by cognitive tasks which stimulate the attention of subjects after an unexpected stimulus [5]. It represents a non-invasive tool to assess cortical signal processing [6, 7] and brain functional state. It can be also elicited by visual, auditory, somatosensory, or olfactory stimuli in different experimental settings. The P300 is involved in cognitive processes resulting from cortical and subcortical areas, especially auditory cortex, hippocampus, and amygdala thalamic structures [8]. Recent studies have confirmed the role of ERPs as prognostic markers in patients with severe brain acquired lesions [9, 10]. P300 seems to be susceptible to stimuli recognition and the presence of this wave is an important prognostic marker for functional recovery in patients with global aphasia [11, 12]. In addition, the increase of P300 latency is associated to post-stroke depression [13].