Electroencephalographic Studies of Injury to the Head

Berger's original observations that the electroencephalogram provided a sensitive indicator of certain pathologic conditions of the brain has received abundant confirmation. Slow "delta" waves, below the normal alpha frequency of 8 to 12 per second, appear from cortical tissue undergoing irreversible degenerative changes or from a reversible depression of cortical function, such as occurs with low blood sugar,¹with certain drugs²or with normal sleep.³The electroencephalogram has also been found useful in the localization of certain focal cortical lesions. Injuries to the head produce both reversible and irreversible changes in cerebral function. Clinical and pneumographic (roentgen) examinations do not always give a clear picture of the nature, extent or localization of cerebral damage. The present study is concerned with the results of electroencephalographic examinations of patients who have suffered various degrees and kinds of injury to the head. The attempt is made to correlate the electroencephalographic