Psychologists refer to the information flowing into our working memory as our cognitive load. When the load exceeds our mind’s ability to process and store it, we’re unable to retain the information or to draw connections with other memories. We can’t translate the new material into conceptual knowledge. Our ability to learn suffers, and our understanding remains weak. That’s why the extensive brain activity that Small discovered in Web searchers may be more a cause for concern than for celebration. It points to cognitive overload.
The Internet is an interruption system. It seizes our attention only to scramble it. There’s the problem of hypertext and the many different kinds of media coming at us simultaneously. There’s also the fact that numerous studies—including one that tracked eye movement, one that surveyed people, and even one that examined the habits displayed by users of two academic databases—show that we start to read faster and less thoroughly as soon as we go online. Plus, the Internet has a hundred ways of distracting us from our onscreen reading. Most email applications check automatically for new messages every five or 10 minutes, and people routinely click the Check for New Mail button even more frequently. Office workers often glance at their inbox 30 to 40 times an hour. Since each glance breaks our concentration and burdens our working memory, the cognitive penalty can be severe.
The penalty is amplified by what brain scientists call switching costs. Every time we shift our attention, the brain has to reorient itself, further taxing our mental resources. Many studies have shown that switching between just two tasks can add substantially to our cognitive load, impeding our thinking and increasing the likelihood that we’ll overlook or misinterpret important information. On the Internet, where we generally juggle several tasks, the switching costs pile ever higher.
The Net’s ability to monitor events and send out messages and notifications automatically is, of course, one of its great strengths as a communication technology. We rely on that capability to personalize the workings of the system, to program the vast database to respond to our particular needs, interests, and desires. We want to be interrupted, because each interruption—email, tweet, instant message, RSS headline—brings us a valuable piece of information. To turn off these alerts is to risk feeling out of touch or even socially isolated. The stream of new information also plays to our natural tendency to overemphasize the immediate. We crave the new even when we know it’s trivial.
And so we ask the Internet to keep interrupting us in ever more varied ways. We willingly accept the loss of concentration and focus, the fragmentation of our attention, and the thinning of our thoughts in return for the wealth of compelling, or at least diverting, information we receive. We rarely stop to think that it might actually make more sense just to tune it all out.