The Problem

Abstract

This is an old-fashioned book. It deals with phenotypes - phenotypes, however, that are not easy to describe since fairly elaborated techniques are required for their identification and, still more, for their adequate description. The mere fact that the living human brain produces continuous electrical activity has been known for about a century, and the first details, the most important patterns of this activity were described almost exactly 70 years ago not by a physiologist but by a practicing psychiatrist, Hans Berger. Since that time the electroencephalogram (EEG) has been investigated from various points of view. The fact that it proved to be a major tool for diagnosis of many diseases - especially those mainly affecting the brain but also other ones in which the brain was involved - was the main reason for their continuous scientific interest. More recently, this interest has narrowed down somewhat. While the EEG has for a long time been the only method giving a clearcut picture of the present functional state of the brain without intrusion into the integrity of the human body, and without undue molestation of the individual to be examined, other such methods have now been developed. Sometimes they provide even more detailed information. However, the EEG is still an indispensable diagnostic tool; especially for differential diagnosis of diseases in which seizures occur - the epilepsies.