Inside Out: Looking at schizophrenia’s inner chaos pg. 2
A wide-ranging array of symptoms characterizes the illness, which profoundly disrupts cognition and emotion, affecting language, thought, perception, affect, and sense of self. Diagnosis encompasses a pattern of signs and symptoms—often including psychotic symptoms, such as hearing imagined voices or espousing false yet fervent personal beliefs—in conjunction with an impaired ability to participate socially or occupationally.
Schizophrenia can occur at any age, but it tends to first become evident between adolescence and young adulthood, somewhat earlier in men than in women but at about the same rate. Retrospective studies reveal signs of cognitive decline—a slide in grades or withdrawal from friends and family, for example—well before the first psychotic “break.” The conditions necessary to produce such neurological havoc remain an enigma.
“That’s why it’s so difficult,” says Pat R. Levitt, Ph.D., director of the Vanderbilt Kennedy Center for Research on Human Development. “It’s a disorder that is complicated because it affects two major mental domains, because it is clearly multi-genic, and because it also has environmental contributors. And yet, out of all the psychiatric disorders that people work on, other than depression, it is the most prominent, affecting one in 100 people.”
It has long been accepted that schizophrenia has a genetic component. The risk for inheriting the disorder is 10 percent in those who have one immediate, or first-degree, family member affected, and about 40 percent if the illness is shared by both parents or by an identical twin.
It’s important to note, however, that the majority of people with schizophrenia have no close relatives who are affected, an indication that there are other factors at play. Epidemiological evidence suggests certain external circumstances, such as viral infection during pregnancy, insufficient prenatal nutrition, or a child’s being born during the winter months or being born in an urban setting, may increase risk.
“This is not to say that you have a higher risk being born in a city hospital rather than in the country,” says Levitt. “It’s probably related to some increased incidence of something a mother is exposed to—infection or perinatal stress, for example—if pregnancy occurs in these different environments.”
Stilling the tempest
Sorting out which behaviors in schizophrenia are linked to genetic changes in the brain, and how those changes impact neurological chemistry and circuitry, has proved challenging. One of the first clues about altered brain chemistry in schizophrenia came in the early 1950s with the introduction of the antipsychotic drug chlorpromazine (trade name Thorazine). Originally used as an antihistamine during surgical procedures, the drug’s sedative properties inspired a psychiatrist to try it on agitated institutionalized mental patients.
View Related Article:
Creativity and madness: are they linked?