Thinking better with depression

Mood disorder may provide an analytical lift

Depression may have an analytical upside. People hospitalized for this mood disorder display a flair for making good choices when many options must be considered one at a time, a new study finds.

Depression may prompt an analytical thinking style suited to solving sequential problems, such as deciding when to stop a house hunt and purchase a property or when to stop playing the field and marry a suitor, say psychologist Bettina von Helversen of the University of Basel in Switzerland and her colleagues.

It’s also possible that depressed people adopt a pessimistic outlook that encourages a thorough evaluation of available options, von Helversen’s team suggests in an upcoming Journal of Abnormal Psychology.

“Depression may improve sequential decision making, which includes some high-stakes choices,” she says.

Von Helversen’s study is the first to demonstrate a thinking advantage for clinically depressed patients, possibly because — unlike previous studies of people with the ailment — the team used a quantitative measure to evaluate the accuracy of realistic social choices, remarks psychologist Paul Andrews of Virginia Commonwealth University in Richmond.

Andrews hypothesizes that depression evolved as an emotional response that induces people to isolate themselves and single-mindedly resolve painful personal problems. “Depressive cognition is more complex than has been assumed by clinicians,” he says.

Over the past 20 years, psychologists such as Paula Hertel of Trinity University in San Antonio have found that depressed volunteers who are not hospitalized do as well as or better than nondepressed peers on various tasks, some demanding careful analysis and others calling for quick or spontaneous answers.

Contrasting studies find that depression, and the rumination it often entails, derail attention and thinking abilities, says Stanford University psychologist Ian Gotlib. People move and react slowly when severely depressed, which could have delayed depressed patients’ choices in the new study and misleadingly made them look analytical and patient, Gotlib suggests.

Waiting too long to select an option undermines sequential decisions as much as jumping the gun, but depressed patients usually put off choices just long enough to make a good call, von Helversen responds.

In her investigation, volunteers tried to choose the best job candidate from a computer-presented sequence of 40 applicants. In a series of trials, 15 depressed patients considered an average of a dozen applicants before selecting a first choice and around 16 before making a second choice. A mathematical model of the task devised by the researchers indicated that patients stopped their applicant searches at key points where there was a strong likelihood of choosing a highly qualified candidate.

In this lab task, rejected applicants could not be chosen later in the selection process. Participants saw a numerical rating of a current applicant’s ranking relative to those already seen.

Severely depressed patients chose higher-qualified job applicants than 27 non-depressed volunteers and 12 depressed patients whose symptoms had moderated with treatment. All depressed patients were recruited from a Berlin psychiatric hospital.

About half of depressed participants, regardless of symptom severity, received antidepressant drugs. Medicated and drug-free patients with severe depression chose job applicants with comparable success, von Helversen says.

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.