Adult, episodic events 3-4 times per year, possibly representing epileptic seizures

What do these waves during wakefulness and sleep represent?

These are three consecutive pages:

Figure 1:

Figure 2:

 The following represent three consecutive pages:

 figure 5

figure 6

figure 7

The following represents the same three pages as above, on the referential montage

The following three pages represent the above waves on a coronal montage:

The following is a different page, taken from sleep

  Figure 2 demonstrates rhythmic theta waves M1-F7, somewhat sharply contoured. The clue to interpreting this correctly is context; as these waves appear, slower waves are seen in the other derivations at the same time (the entire recording slows subtly). The  EEG demonstrates no eyeblinks, indicating the patient is relaxed and therefore prone to drowsiness, especially at this time of night. Although theta waves are not obvious at F8, they certainly are present. Hence, these theta waves likely represent an asymmetric form of drowsiness. It is noteworthy that theta waves like this are virtually absent from the rest of the recording over 24 hours.

Although you might be tempted to call  the sharply contoured waves at F7-T3 on page 6 a sharp wave/inter-ictal epileptiform discharges, you should avoid doing so as,

 1. The wave is symmetric

 2. The  wave has no  succeeding slow wave

3. The wave does not disrupt the background

4. The wave is not remarkable in respect of its amplitude when compared to the background rhythms

5. The final 2 pages represent sequences of waves, nearly identical to the above isolated wave.  In fact, if you look at the referential and coronal montages  representing the way seen in Figure 6, you will notice that it is part of a sequence of waves.

Hence, this is no more than an isolated wicket spike. Such waves are repeatedly over-interpreted in many recordings and accompanying reports sent to me for review. 

This patient's EEG is normal.