Brain death--a review of the concept

The early origins of the concept of brain death have been retraced. Using practical examples from clinical experience it has been demonstrated that conventionally, cardiac death is always accompanied by brain death. Cardiac death implies brain death. The two are inseparably linked or coupled. Death on a ventilator uncouples the two, revealing death of the brain as the true determinant of the cessation of a person's life and the heartbeat as a false measure.

Electroencephalography 60 years later

The birthday of Electroencephalography (EEG) is dated back to the 22nd of April 1929. On this date Hans Berger submitted the first of his 14 contributions "Uber das Elektrenkephalogramm des Menschen" to the "Archiv für Psychiatrie und Nervenkrankheiten" for publication. Therefore in 1989 Electroencephalography was 60 years of age. In spite of controversy over its usefulness during this period, Electroencephalography substantially contributed to progress in medicine. Today is the beginning of its Renaissance due to a dramatic diversification of Clinical Electroencephalography into applied neurophysiological specialties. Progress became possible by the introduction of new techniques. However it will become obvious that new instrumentations cannot replace intelligence and human understanding. The dispute of importance and nonsense, use and misuse of Electroencephalography is without doubt useful and stimulates new orientations.

Electrophysiological brain maturation in premature infants: an historical perspective

The EEG is an excellent method for measuring brain maturation in premature neonates. Characteristic patterns typify each conceptional age (CA) (age in weeks from conception) and allow the experienced reader to predict within +/- 2 weeks the infant's CA. This paper reviews from an historical perspective (beginning with Berger) the dramatic changes the EEG undergoes from early premature birth (CA, 26 weeks) to term (CA, 40 weeks). The important features of normal EEG development are discussed as well as the clinical significance of an apparent arrest or delay of the normal developmental process, the so-called "dysmature" pattern. It is proposed that close attention to the stage of brain maturation in normal and abnormal EEGs might allow more accurate timing of the brain insult in infants with neurological sequelae.

Sixty years of clinical electroencephalography

As a result of painstaking studies carried out over a period of almost 30 years, the German neurologist and psychiatrist Hans Berger, of Jena, published the first paper on the human electroencephalogram (Uber das Elektrenkephalogramm des Menschen') in 1929. Clinical electroencephalography, which reached a zenith in the 1950s and 1960s, increased the range of diagnostic techniques available for a series of brain diseases and revolutionized the study of epilepsy. Today, conventional electroencephalography no longer yields startling scientific discoveries. Nor can it complete with computer tomography and magnetic resonance imaging, in the diagnosis of structural disorders of the brain. In spite of this, the scope of its uses continues to increase and it remains an indispensable instrument of neurophysiological diagnosis, especially in its capacity as a 'seismograph' of the brain. The trend that is apparent throughout the world to cut back clinical electroencephalographic units in favor of other neurophysiological investigative techniques is both unjustified and dangerous. If it continues, it will inevitably lead to a decline in epileptology, which is an essential part of the work of many different medical specialists both in practice and in hospitals.

[The French Society of EEG and Clinical Neurophysiology is 40 years old]

The historical reminder of the foundation of the French EEG Society and the changes which have occurred during its operation show the worry of the Society for a better efficiency all along this last fourty years. A general survey of the scientific activities disclose the contribution of the society in the papers first published in the Revue Neurologique, and, after 1971, in the Revue d'EEG et de Neurophysiologie clinique de Langue française. The French participation in other clinical neurophysiological or scientific meetings in France and abroad is underlined by the important role it has played in the life of the International Federation for EEG Societies. Training of specialized doctors and technicians in the domain of the functional exploration of the nervous system has been a standing preoccupation of the Society, with the teaching of the so-called "Attestation d'EEG" in French universities and the training of technical personnel in specialized schools.

[Fiftieth anniversary of Hans Berger's publication of the electroencephalogram. His first records in 1924--1931 (author's transl)]

For the fiftieth anniversary of Berger's first EEG publication, some of his early recordings obtained between 1924 and 1931 are discussed and illustrated. Examples of his protocols from the Freiburg Berger Archives are reproduced. Three types of Berger's early investigations are described: (1) String-galvanometer recordings obtained between 1924 and 1926, mainly from trephined patients with cerebral diseases, which usually showed brain waves slowed to 6--8 per second; (2) Direct recordings from the cortex and white matter proving the cortical origin of the EEG in 1930; (3) Typical unpublished EEG recordings of epileptics and of petit-mal attacks obtained in 1930 and 1931. Berger's first six papers published between 1929 and 1933 described nearly all the main EEG findings of cerebral diseases and the EEG alterations of normals during attention, sleep, and narcosis, but they did not report on convulsive potentials in the EEGs of epileptics. Berger had, however, obtained excellent records of epileptic EEG features, here depicted in Figs. 4 through 7. These remained unpublished until 1933 and 1938, because Berger suspected that they contained artifacts caused by blinks and facial movements which he had recorded in his controls (Fig. 4). Only in 1933, after other authors had described large amplitudes of convulsive potentials in the cortex of animals, did Berger publish parts of the EEGs of a petit-mal attack and of focal attacks in progressive paresis. In 1938, Berger presented the EEG of the beginning of a petit-mal attack with large 3/s spikes and waves recorded in 1931 which were similar to those described by Gibbs and coworkers in 1935. In 1933 and 1938, Berger interpreted the abnormal brain potentials of epileptics as signs of a preconvulsive state of the forebrain and suggested that the periods of 3/s waves were cortical correlates of an epileptic absence.