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. 2005;2(4):147-54.
doi: 10.7150/ijms.2.147. Epub 2005 Oct 1.

Characterization of N200 and P300: selected studies of the Event-Related Potential

Salil H Patel  1 , Pierre N Azzam
Affiliations

Characterization of N200 and P300: selected studies of the Event-Related Potential

Salil H Patel et al. Int J Med Sci. 2005.

Abstract

The Event-Related Potential (ERP) is a time-locked measure of electrical activity of the cerebral surface representing a distinct phase of cortical processing. Two components of the ERP which bear special importance to stimulus evaluation, selective attention, and conscious discrimination in humans are the P300 positivity and N200 negativity, appearing 300 ms and 200 ms post-stimulus, respectively. With the rapid proliferation of high-density EEG methods, and interdisciplinary interest in its application as a prognostic, diagnostic, and investigative tool, an understanding of the underpinnings of P300 and N200 physiology may support its application to both the basic neuroscience and clinical medical settings. The authors present a synthesis of current understanding of these two deflections in both normal and pathological states.

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Conflict of interest statement

Conflict of interest: The authors have declared that no conflict of interest exists.

Figures

Figure 1
Figure 1
Archetypical waveform stimulus-locked representing event-related components of EEG waveforms. N.B., negative waveforms may be represented by upward deflections in traditional notation, which reverses the voltage axis
Figure 2
Figure 2
Example multichannel ERP waveforms arranged in a topographic map, from superior “birds-eye” representation (A = anterior scalp, P=posterior scalp)
Figure 3
Figure 3
Schematic representation of Oddball (1) and Modified Oddball (2) task paradigms. White box represents a standard or nontarget stimulus; black box represents variant target stimulus; circle represents a deviant, unexpected stimulus presented to the subject
See this image and copyright information in PMC

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