Johns Hopkins Gazette: November 3, 1997

In Brief

Right side of brain does work for worriers

Hopkins researchers think they have identified sites in the brain where "worrying" takes place. Using brain scans that measure blood flow variations, the scientists concluded that several structures on the right side are the site of anxious thoughts.

For the study, presented at the annual meeting of the Society for Neuroscience, 10 volunteers made short tapes describing their worries: recent family crises, stress in the workplace, financial problems, or other troubles. After volunteers listened to the same tapes, their brains were immediately scanned with a technique called functional positron emission tomography, which detects differences in blood flow, an indicator of brain activity.

Subjects also were scanned after listening to "neutral" tapes about flower auctions and flower arrangements.

"We subtracted the scans to find the difference, and it was clear that several areas on the right became more active during worrying," says Rudolf Hoehn-Saric, director of the anxiety disorders unit at Johns Hopkins.

"We saw an increase in the right frontal lobe, the planning and decision-making part of the brain, and in other areas on the right that are involved in arousal, self-examination and processing of new inputs," says Hoehn-Saric. The other areas included the basal ganglia, which coordinate and process messages from various parts of the brain; the cerebellum, whose functions include storing "routines"--frequently used patterns of thought or movements; and the pontine nuclei, which regulate arousal.

The new finding makes sense in light of historic evidence that the left side of the brain is involved in analytical thinking and the right in emotional, according to Hoehn-Saric.

"Worrying occurs when no easy solution is available, and the solution is often derived emotionally rather than rationally," he notes.

Scientists plan to follow up with studies of patients with anxiety disorders, psychiatric conditions that disable them with overwhelming concern about a particular aspect of their lives, such as cleanliness or their physical surroundings. Comparisons of the two studies could help scientists find anxiety disorders' origins in the brain.
--Michael Purdy


Potential test for Lou Gehrig's disease at hand

Good results in preliminary studies of a potential diagnostic test for amyotrophic lateral sclerosis have led Hopkins scientists to call for an expanded trial immediately.

At this week's meeting of the Society for Neuroscience in New Orleans, Hopkins neurologist Jeffrey Rothstein is asking physicians "to send us cerebrospinal fluid from their patients to give us a larger sample to evaluate the test."

Currently, diagnosis of ALS, also known as Lou Gehrig's disease, is indirect, requiring months of tests to exclude other diseases. "During this time, motor nerve cells are dying," Rothstein says. "If our new test works, doctors can check for ALS at the first sign of ALS-like symptoms and begin treatment much earlier."

A drug called riluzole, approved in 1995 by the Food and Drug Administration, can slow the disease, although it is unable to halt it. Other drugs are under study, and experts believe that earlier application of those treatments could significantly improve the quality of patients' lives.

Early studies that identified abnormalities in proteins related to ALS were funded in part by the Cal Ripken/Lou Gehrig Fund for Neuromuscular Research, a fund for research into ALS and other neuromuscular diseases created in 1995 when Ripken broke Gehrig's long-standing record for consecutive games played.
--Michael Purdy


Best test and treatment for stroke patients determined

Researchers at the School of Public Health have determined which combination of diagnostic and treatment techniques is most cost-effective in preventing repeated strokes in patients who have had their first stroke.

Those stroke patients who receive a relatively new imaging procedure called transesophageal echocardiography and have their treatment based on the test results likely will have significantly fewer strokes later on, with improved quality of life and decreased medical costs. In contrast, another older imaging method widely used in stroke patients, transthoracic echocardiography, often does not see clots in a particular region of the heart where many clots form, thus leaving patients vulnerable to recurrent strokes and higher medical costs.

The study appeared in the Nov. 1 issue of the Annals of Internal Medicine.

Because strokes that are caused by clots traveling in the blood (emboli) carry the greatest risk of subsequent emboli-induced strokes, identifying potential sources of cardiovascular emboli and then dissolving any new clots with anticoagulation therapy is crucial in reducing the incidence of later strokes. Anticoagulation therapy, however, cannot be given indiscriminately to all stroke patients because it can sometimes rupture weak blood vessels in the brain and trigger a hemorrhagic stroke.

By reviewing evidence on case histories of first-time stroke patients in the medical literature, the researchers were able to compare the benefits, risks, and cost effectiveness of various imaging strategies.

Neil R. Powe, director of the school's Evidence-Based Practice Center and senior author, said, "Although a variety of cardiovascular imaging techniques are now used to locate emboli in patients after stroke, until now the most cost-effective technique for preventing future strokes and improving quality of life had not been determined. Physicians often perform tests sequentially, ordering the least costly and invasive test first followed by the more expensive. For first-time stroke patients, this is not cost-effective and may not be in the patient's best interest."
--Lisbeth Pettengill


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