Consider two questions. First: Who are you? What makes you different from your peers, in terms of the things you buy, the clothes you wear, and the car you drive (or refuse to)? What makes you unique in terms of your basic psychological make-up—the part of you that makes you do the things you do, say the things you say, and feel the things you feel? And the second question: How do you use the internet?
Although these questions may seem unrelated, they’re not. Clearly the content of your internet usage can suggest certain psychological characteristics. Spending a lot of late nights playing high stakes internet poker? Chances are you are a risk taker. Like to post videos of yourself doing karaoke on YouTube? Clearly an extravert. But what about the mechanics of your internet usage—how often you email others, chat online, stream media, or multi-task (switch from one application or website to another)? Can these behaviors—regardless of their content—also predict psychological characteristics? Recent research conducted by a team of computer scientists, engineers, and psychologists suggests that it might. Indeed, their data show that such analysis could predict a particularly important aspect of the self: the tendency to experience depression.
First, the research team asked over 200 volunteers to fill out a survey about “recent affective experiences;” what the volunteers didn’t know was that a well-known measure of depression—the Center for Epidemiological Studies Depression (CES-D) scale—was embedded within this survey. The researchers then correlated scores on the hidden depression scale with individual trends in internet usage, grouped into three categories: “aggregate,” which indicated how much information was being sent and received over a network, “application,” which indicated the broad category of program that was being used (e.g., email, surfing the web, downloading media), and “entropy,” which indicated the degree of randomness in information flow (essentially, the extent to which someone was sending and receiving information to multiple net-based resources at once).
Again, researchers didn’t know what people were looking at on the internet (for example, depression support groups—a dead giveaway), but merely how they were using the internet. None of the data categories gave specific information about what websites people were visiting, the content of their emails or chats, or the types of files being downloaded—they simply indicated the extent to which people used different broad categories of net-based resources, as well as differences in people’s tendency to use many resources at once.
It turns out that very specific patterns of internet use are reliably related to depressive tendencies. For example, peer-to-peer file sharing, heavy emailing and chatting online, and a tendency to quickly switch between multiple websites and other online resources all predict a greater propensity to experience symptoms of depression. Although the exact reasons that these behaviors predict depression is unknown, each behavior corresponds with previous research on depression. Quickly switching between websites may reflect anhedonia (a decreased ability to experience emotions), as people desperately seek for emotional stimulation. Similarly, excessive emailing and chatting may signify a relative lack of strong face-to-face relationships, as people strive to maintain contact either with faraway friends or new people met online.
These data are particularly important for several reasons. Depression is both prevalent and dangerous. Recent estimates from the Centers for Disease Control and Prevention (CDC) indicate that around 10 percent of adults in the United States currently suffer from clinical depression—depression that consists of symptoms such as disruptions in eating, sleeping, and concentration patterns, lack of interest in daily activities, and consistently feeling like a failure. These estimates are even higher for other segments of the population; for example, a 2011 report by the American College Health Association found that 30 percent of college students have “felt so depressed that it was difficult to function” within the past year.