We all do it. We’ve all been asked at one point or another to send out an email solicitation at 5:30 on a Friday afternoon to a huge list of people.

But somewhere, lingering in the back of our minds, are questions about the efficacy of those late-week, late-day email pushes. Is this something that really works, emailing people just as they begin the weekend? Or I am just doing this to check off a box on somebody’s to-do list? What’s the objective? How successful is this kind of tactic?

I discussed some of these questions at a panel on online fundraising and list building at the annual Personal Democracy Forum Conference in New York last week.

Something we didn’t discuss – but should have – is an issue that many of us face every time we check our Blackberries over dinner: being constantly connected to each other through technology makes our heads explode. We’ve become cognitively overloaded.

We juggle multiple communications tools at the same time, including real world communications, and we have an endless amount of information to catch up with (especially people who work in advocacy, public affairs, and politics). Through constant connection to each other and to information, we look for patterns in all those bits of data that are most relevant to what we do (or need to do).

Linda Stone, a software executive from both Apple and Microsoft, calls this existing in a state of “continuous partial attention” (Check out a great video of Linda explaining this in a lecture titled “Attention: Yours, Mine, Ours” from SIME 09 at BoingBoing)

She argues that we are motivated not to miss anything, to be a live node on the network. And, she says that the way our bodies respond to communications changes when we multi-task – especially when we check email.

Think about your body posture when you check email. Most of us hunch over our keyboards or our mobile devices. Sometimes our breathing stops when a new email comes in. We tense up.

As Stone puts it,

We become hyper-alert. We become vigilant. We create an artificial sense of constant crisis. We go into a flight-or-fight or stress responses physiologically. It isn’t good or bad. It just is.

Stone argues that we are suffering from email apnea. Every time a new email comes in, and we forget to breathe or, worse, we overreact and become emotional, we activate the flight-or-flight mechanisms in our bodies. When we check email that reaction causes our bodies to prepare to run from a predator – or kill it.

Combine email apnea with the fact that when we communicate online, we are deprived of the kinds of rich, nonverbal cues that allow us to sense the subtleties of emotions in the people we communicate with. We can’t tell if the person sending us an email is being flirtatiously sarcastic or wearily sarcastic or angrily sarcastic or bitterly sarcastic or sadly sarcastic, for example.

We’re more likely to read extreme emotions and anger into what other people write to us. We’re quick to respond with extreme emotions and anger. We’re less likely to forgive other people for what they write. We’re more likely to make excuses for our own poor email behavior.

This leads me to believe that our email inboxes are really the equivalent of some kind of asylum.

Now imagine it’s Friday afternoon, and you’re picking your kids up from school to go out for family Friday pizza. Your Blackberry goes off.

Congratulations! You just received more advocacy and political email! Delete.

Writers like Linda Stone and Clay Shirky now argue that people are evolving to help us handle email apnea and cognitive overload. We’re developing ways to filter the kinds of emails and advertisements that hit us a million different ways online. In a recent speech on Information Overload vs. Filter Failure at Web 2.0 Expo in New York, Shirky argued that this kind of overload isn’t new. Humans have faced these issues since the invention of the printing press.

What we’re dealing with isn’t information overload. It’s filter failure. . . .This is a general system design problem for our era. . . . It isn’t about access to information. It’s about flows and access to flows. It’s about designing a system that accommodates good information and good conversation. When you feel yourself getting too much information, ask yourself, ‘what filter just broke.’

Sick of getting too much political or advocacy email? Block it. Delete it. Flag it as spam. Forget it before you even open it.

As we convince more of our clients to invest money in online tactics like email (or online advertising), we need to realize that the more sophisticated we get, the more sophisticated people will get at filtering us out.

That’s our challenge right now: finding tactics that work extraordinarily well for our clients and also give them the comfortable, satisfactory feeling we all get when we can check something off a list.

The fact is that a lot of us already know what to do instinctively. We know what makes us open an email, send a letter to our Member of Congress, or donate money. We know how we like to be treated.

And that’s precisely why the best digital strategy results from collaboration between people who know the tools and people who know people. Together we can combine what we all know about being human and being persuasive with technological tactics that engage and activate people, instead of accelerating that fight-or-flight instinct.