Images of conflict: MEG vs. EEG (magnetoencephalography vs electroencephalography)

Article Abstract:

For decades, electroencephalography (EEG) has been a primary tool for researchers trying to understand the working human brain, as well as for neurologists attempting to pinpoint the problems of some patients. Technological improvements in a new process, magnetoencephalography (MEG) have prompted some researchers to suggest the newer device will be a big improvement. EEG works by recording electrical activity on the scalp. While electrical activity is related to events in the brain inside the skull, the ability to pinpoint the location of electrical signals in the brain is necessarily limited. MEG, on the other hand, uses sensitive detectors to sense changing magnetic fields outside the head. Since these magnetic fields are created by electrical activity within the brain, recordings may be made of brain activity by this method. The proponents of MEG say it is more precise and will allow neurologists to determine the location of events within the brain with greater precision than is possible with EEG. However, a prominent researcher has recently stated that this is not so. Controversy surrounding new technologies is not uncommon, but in this case the individual stating that MEG will not live up to expectations is David Cohen, the MIT physicist whose discoveries lead to the development of MEG. Cohen feels that the claims made for the precision of MEG are overblown. MEG supporters say that while Cohen's original work was excellent, the field of MEG has advanced greatly since then, and Cohen's lack of understanding of the brain has prevented him from remaining at the forefront. This controversy would not be so important were it not for the difference in cost between EEG and MEG. An excellent EEG may be purchased for $50,000, but a MEG costs about $3 million. If the EEG can do the job just as well, there is little incentive for the use or further development of the MEG. (Consumer Summary produced by Reliance Medical Information, Inc.)

Electroencephalography, Magnetoencephalography

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Righting the antibiotic record

Article Abstract:

The history of the discovery of antibiotics was the topic of a symposium at Rockefeller University in New York City on October 23, 1989. Although most people give credit to Alexander Fleming as the first person to discover antibiotics, substances that kill bacteria that cause infectious diseases, science historians say that the honor should go to Rene Dubos. Discoveries in science occur either by the combination of luck and hard work or by a systematic approach to solving a particular problem. The discovery of antibiotics occurred in both manners. In 1928, Alexander Fleming discovered that a substance obtained from mold, which he named penicillin, killed bacteria. He had returned from a vacation to find that some bacteria he was growing were contaminated with mold and that the bacteria surrounding the mold were lysed or dissolved. Although the circumstances surrounding the findings were fortuitous, as the weather had to stay within a certain temperature range for the mold to grow, Fleming was observant enough to notice the finding. However, the substance that killed the bacteria was not isolated nor were its properties understood until the 1940s, when Howard Florey and Ernst Chain discovered the value of penicillin as an antibiotic, which is now used in humans and animals to kill bacteria and cure various infectious diseases. In 1939, Rene Dubos reasoned that a bacterium must exist in nature to dissolve the outer surface of another bacterium that was responsible for pneumonia. Using microbiological techniques, he systematically looked for this organism, finding an organism which produced a substance containing gramicidin. Gramicidin was too toxic to be used in humans but it was the first antibiotic to be used in animals in 1939.

Antibiotics, History, Penicillin, Penicillins, Gramicidins, Dubos, Rene J.

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The epilepsy "cure": bold claims, weak data

Article Abstract:

An article published in the Sep 1989 issue of the International Journal of Neuroscience stated that 20 patients with epilepsy, a neurological disorder characterized by episodes of seizures, had been cured after treatment with an electronic device which created a magnetic field within the patient's brain. Other investigators in the field were angry that the article was printed, as the data and conclusions were unsubstantiated. The electronic device that was used was not described and no details of the techniques or procedures were given. There was no follow-up on the patients, who are normally followed for three to five years after any treatment for epilepsy. The criticisms of peer investigators will be published in another issue of the journal. When the authors of the article were asked for a comment on the criticisms, they responded by asserting that anything new will always be criticized. In addition, they claimed that details of the device were not explained in order to protect a patent that was pending. The editor of the journal claims that some journals have less rigorous standards than others, especially international journals that publish articles from laboratories that do not have the same resources as others. Scientists, on the other hand, claim that loose standards, especially in articles about a cure for a disease, are a social injustice to people with the disease, who may hear about it and think that there is hope of a cure for their disease. The lowering of standards and the publication of unjustified articles can give a bad name to science in general.

Care and treatment, Evaluation, Medical equipment, Epilepsy, Brain research

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