Secret to identifying interictal spikes?

[lgroomes]

Basically I'm a research assistant starting med school next year, and my PI wants me to learn to identify interical spikes (I realize it sounds ridiculous). We have 2 hours of ECoG data from 8 surgical patients in which 5 epileptologists have marked interictal spikes. For the first patient the spikes are very obvious with beautiful with slow wave discharges following. However the spikes for the second patient are seemingly different. I really can't see a difference between a lot of spikes that are and are not considered interictal spikes. This is probably very naive of me but is there a book (or part of a book) about identifying interictal spikes? How do neurologists learn to identify them, just practice with feedback? Most of the papers that I have read are about algorithms which isn't very helpful. Any advice would be greatly appreciated! Thanks!

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[exgatr]

There definitely isn't an easy way to do it. It comes down to experience really.

The spike and slow wave discharges are easy to identify because they pop out at you visually.

Isolated spikes are harder to see, especially if they are small.

At the most basic you need to know:

1. A spike lasts less than 70 ms
2. It should have a "field" around it, which is to say that it should involve more than one electrode in some way. Typically the surrounding electrodes have changes that look similar to the spike focus, but are lower in amplitude.
3. Artifacts-- there are a lot less of these with grids than with surface electrodes, but they still happen from time to time.

If you want an east read, check out Practial approach to electroencephalography by Mark Libenson