EEG vs. Perfusion

The following graph from a publication by Leuchter et al. (1999) on cortical perfusion and EEG is quite helpful in interpreting EEG frequencies and what they represent. The graph below shows EEG frequency on the X-axis and the partial correlation between EEG frequency and relative perfusion. It can be clearly seen that the alpha band indeed can be seen as the iddling rhythm of the brain since in the Alpha band there is the biggest negative partial correlation with perfusion, indicating that the metabolic activity in the underlying cortex is lowest during that activity. Furthermore, with increasing frequency in the beta band there is an increasing partial correlation indicating increased metabolic activity in the underlying cortex. Note there is also a high positive correlation for low frequent activity in the 0-4 Hz frequency band.

 

Literature

Leuchter AF, Uijtdehaage SH, Cook IA, O'Hara R, Mandelkern M. Relationship between brain electrical activity and cortical perfusion in normal subjects. Psychiatry Res. 1999 Apr 26;90(2):125-40