Our brains are littered with passwords and alphanumeric combinations that span all levels of necessary corporate and personal security—from bank accounts and PINs, to work-related e-mail and network log-ons, to e-commerce and social networking sites.

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A neurological researcher who is fully appreciative of the dizzying increase in passwords and other things to memorize, however, argues that we all can remember much more if we practice visualizing the information we want to recall.

But first: What should we actually try to commit to memory these days? It seems like a legitimate question. (Personally, here's how many computer-related passwords I can remember off the top of my head: three. I figure I have a total of 50 or so passwords which I need to recall during a typical month.)

Recent research from Ian Robertson, professor of psychology at the Institute of Neuroscience and School of Psychology at Trinity College in Dublin, Ireland, illustrates the growing amount of alphanumeric clutter in our heads: the average person now has to remember five passwords, five PIN numbers, two number plates, three security ID numbers and three bank account numbers just to get through everyday life.

A 2007 study of Web users by Microsoft Research found that the average user has 6.5 Web passwords, each of which is shared across almost four different websites. In addition, each user has about 25 accounts that require passwords, and types an average of 8 passwords per day.

Too Much To Remember?

Not surprisingly, Robertson's research found that nearly 60 percent of those studied felt like they couldn't possibly remember all of these numbers and letters that they were supposed to. A consequence of this "information overload" was that most users today create weak passwords (dog's or child's name usually top the list) or rely heavily on technology to create or store of the alphanumeric data.

Vendor solutions to the password problem, such as Passface's facial-recognition technology, abound. Researchers, like those at Microsoft, have explored the value of tech-assisted visual aides, like digital ink blots. And security experts such as Bruce Schneier have laid out their own strategies. (See CSO's take: "How to Write Good Passwords.")

To which Robertson responds: "People are incapable [of remembering passwords] because of the particular ways they have been taught to remember," he says. "We can use our brains much more than we do. And if we could be bothered, we could happily remember two dozen passwords using some fairly standard memory methods."

Flexing the Brain's Memory Muscles

The brain is just like any other part of our body when it comes to use, Robertson contends: "Use it or lose it." His recent study showed the generational differences and how the brain can seemingly atrophy. In Robertson's survey, for example, almost a third of those under 30 couldn't remember their home telephone number, which was usually stored on their mobile device or on a piece of paper.

"I was astonished that a significant percentage of people didn't know their own cell phone number or landline number without looking it up," Robertson says. "And this was much more so of younger people, who are reliant on technology, and that's leading to the underuse of certain areas of the brain." (A recent article in The Atlantic, by Nicholas Carr, asked if Google was making us stupid—was the Internet negatively influencing our brain's processing abilities, especially in how we read?)