The relationship between the electroencephalogram and the intelligence level has been studied by many authors. In recent years, with increasing knowledge of the types of tracing seen in normal children, it seemed pertinent to review a new group of cases.
A great deal of the early work was done by Kreezer * and by Kreezer and Smith. This work was primarily concerned with the relationship between mental age and various attributes of the alpha rhythm, such as frequency, amplitude, and alpha index. The results were suggestive of a relationship between development of alpha and intelligence, but they were not clear-cut.
Studies by Rahm and Williams, Knott, Friedman and Bardsley, and Gunnarson have also failed to reveal any definite change characteristic of mental deficiency. Other authors, Putnam and Merritt, Posey, and Cook, have discussed in detail the relationship between mental deficiency and epilepsy. That there is a close connection between these two