Hippocampus and superior colliculus: Congruent EEG activity demonstrated by a simple measure

Simultaneous EEG recordings were taken from the superior colliculus and the hippocampus in awake, freely moving albino rats. A simple method for scoring the synchronization-desynchronization shifts in each of the two structures allowed for a quantitative assessment of the congruence in activity between the two recordings. Intrarater and interrater reliability measurements were high, indicating that the method may be useful. It is also inexpensive particularly when long time periods of EEG activity require analysis. The congruence between the hippocampus and superior colliculus EEG recordings is of interest and, to our knowledge, has not been reported previously.