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5: Referencing and Other Channel Operations

  • Page ID
    87952
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    Learning Objectives

    In this chapter, you will learn to:

    This chapter dives deeper into channel operations, especially with respect to how the reference electrode works and how you can re-reference your data. Once you know what you’re doing, re-referencing the data will take you just a few seconds, and many researchers don’t give it much thought. However, the reference has an enormous impact on your ERP waveforms, so you really need to understand what you’re doing when you reference or re-reference your data.

    The exercises in this chapter are designed to give you greater insight into what the reference site does, why we need to reference the data, and how re-referencing the data can clarify or obfuscate the results depending on what new reference you choose. We’ll also discuss the mechanics of re-referencing in ERPLAB so that you can have confidence that you’re doing it correctly.

    We’ll start with simulated data so that you can see how the original and referenced data on the scalp are related to the underlying neural generator. The simulations use Excel rather than ERPLAB, which makes it easier to see exactly what’s going on. You can use Google Sheets instead of Excel, if you prefer. I’m assuming that you know the basics of spreadsheets, including how an equation in one cell can compute a value on the basis of other cells.


    This page titled 5: Referencing and Other Channel Operations is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Steven J Luck directly on the LibreTexts platform.

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