P&S Journal: Spring 1996, Vol.16, No.2
Suicide Researcher Brings Unique Studies to Columbia
|Dr. John Mann, a leading expert in suicide research, has brought to P&S the only federally funded study on suicide behavior across the life cycle. His studies of biological markers for suicide earned him the American Suicide Foundation's 1995 Research Award.|
"One of the factors involved in determining the threshold for suicidal behavior appears to be the activity of the serotonin system," explains Dr. Mann, professor of psychiatry and director of neuroscience at the New York State Psychiatric Institute and of the Mental Health Clinical Research Center for the Study of Suicidal Behavior, which draws on the disciplines of neurochemistry, neuropathology, and brain imaging. "The more active it is, the safer you are."
Dr. Mann joined P&S and the Psychiatric Institute after serving as director of the University of Pittsburgh's Laboratories of Neuropharmacology. He and his research team have improved understanding of site-specific activity in the brain and directed their efforts to studying abnormalities in the lateral and orbital prefrontal cortex. This is based on knowledge that individuals, after sustaining injuries to the prefrontal cortex, often are less inhibited from acting and speaking inappropriately.
|Dr. John Mann|
A specific biological abnormality appears to be associated with many psychiatric disorders and correlates with a vulnerability for suicide. Depressed patients may exhibit the same severity and number of episodes of illness, but members of a high-risk group (group A) may make lethal attempts to end their lives while members of a low-risk group (group B) do not.
"The serotonin system in group A may be blunted. Often the high-risk group tends to be undermedicated," says Dr. Mann. "We need to distinguish the characteristics of the high-risk group from the low-risk group then work toward a clinical recommendation."
Throughout years of research, Dr. Mann and his colleagues, Dr. Victoria Arango and Dr. Mark Underwood, have developed a method of looking at biochemical activity by examining slices of brain tissue obtained during autopsy at a resolution many times greater than that allowed by a PET (positron emission tomography) scanner. The resolution permits examination of the serotonin activity at the cellular level.
"We are conducting postmortem research comparing the brain tissue of suicide victims with those dying from other causes, as well as interviewing families in order to determine a diagnosis," Dr. Mann says. "One factor may not be sufficient to predispose an individual to act on suicidal tendencies."
As a result of these postmortem studies, Dr. Mann and Dr. Kevin Malone, assistant professor of clinical psychiatry, have developed a method for visualizing serotonin function in the brain of living patients using PET. The PET center at CPMC is a major resource for this kind of study. Dr. Mann and Dr. Malone have demonstrated for the first time a deficient serotonin response in depressed patients.
A native of Australia, Dr. Mann came to the United States in 1978 as research assistant professor in psychiatry at NYU. After holding positions at Cornell and Rockefeller universities, he became professor of psychiatry at the University of Pittsburgh and research psychiatrist at Western Psychiatric Institute in 1989.