We’ve been hearing a lot lately about how communications technology reduces productivity and makes people stupider — mainly by interrupting people too often, in too many ways. Some studies have gone so far as to quantify the decline in productivity (25 to 30 per cent) due to multitasking. These researchers imply that we’d all be better off turning off our phones, shutting down instant messaging and e-mail, and logging out of Facebook, MySpace and Linked-In. I think they’re nuts.

For one thing, many other studies (including some by yours truly) have documented a net improvement in productivity due to real-time collaboration. For example, a major intelligence agency was able to reduce the time required to validate intelligence alerts thanks to blogging. Cisco saw an order-of-magnitude improvement in the quantity and quality of ideas generated by using social networking tools. And sales forces around the globe have increased their responsiveness to customers using just-in-time-fetch-the-expert tools such as mobility and presence.

But there’s a bigger reason I think the studies showing that communications makes people less intelligent are wrong, and that more effective communication actually makes us smarter. There’s a growing body of evidence that human intelligence is the result of developing brain mechanisms that enabled us to communicate effectively with our peers.

Language was such a potent survival tool that tribes who had language survived while those who didn’t died out — and our brains adapted accordingly. Essentially, our ancestors’ brains rewired themselves to enable us to speak, repurposing complex brain systems (such as the ability to differentiate smells and the ability to navigate) to serve the purpose of enabling language. The ability to repurpose brain systems — called “neuroplasticity” — is a surprising phenomenon that’s been researched extensively in the past few years. There’s a great book on the topic called The Brain that Changes Itself, by Norman Doidge. The basic idea is that if you really need to do something, your brain will rewire itself to enable you to do it by “stealing” neural circuitry from some other function.

At any rate, the ability to communicate effectively appears to be hard-wired into human brains (although the choice of language is culturally dependent). And evolutionary biologists cite language ability — as opposed to tool-making, the ability to walk upright or even the ability to work a television remote control — as the single biggest differentiator between ourselves and nonhumans.

In other words, communications gave our ancestors the ability to survive and outlast Neanderthals — pretty powerful evidence that communications makes us smarter, not stupider. With the Internet, IM, social networking and mobility, the intensity and scope of communications increases dramatically. Obviously there’s a time and place for multitasking. It’s difficult to write War and Peace or practice brain surgery while simultaneously texting, Twittering, e-mailing and carrying on a phone conversation. For situations in which you need to maintain intense focus, I respectfully suggest making effective use of the “off” switch.

But overall, you can definitely say that your phone is making you smarter. Modern-day Neanderthals, your days are numbered.