There’s a particularly tedious kind of speaker that ostentatiously tries to teach his audience something by having the audience repeatedly recall some big idea, or some list, or the seven levels of . . . knowledge about a certain subject.  The hapless audience has to shout out, or chant in unison, or (worst of all) individually prove that they have been paying attention.

Perhaps it’s appropriate for small children learning arithmetic, but once we’re out of grade school, we deserve better.

And now there’s a good neuro-scientific reason not to pointlessly chant rote learnings.  A new study shows that every time we go through the act of recalling an idea, list or level, our brains jettison something else.  We forget one old thing for every one new thing we remember.

We’ve known for a long time that memory is a fragile thing at best, that it’s unreliable, and transient.  We’ve also known that listening – such as the kind of listening that an audience does – is a particularly bad way to try to remember things.  As I’ve reported before, the retention rate for things a speaker tells you, if you’re sitting in the audience, is something like ten to thirty percent, depending on who’s studying you.  And slides do not help retention, much as Microsoft wished it were otherwise.  In fact, slides may make retention a little worse.

OK, so that’s what we’ve known for a while.  But to learn that memory is a zero-sum game is distressing, perhaps, for speakers, because essentially we’re asking audiences to forget things as fast as we pour new ideas into their heads.

But before we speakers throw in the verbal towel and stop trying to get our audiences to remember anything at all, it’s worth turning this science on its head in order to see that, rather than being a discouraging fact, in the right light, this study is very good news indeed.

How so?

Modern audiences are pictures of distraction.  Before a speaker starts, they’re on their mobile phones, desperately trying to get one last email or text message sent before they’re temporarily deprived of that form of connection.

Bloggers (and speakers) regularly report that people now have the attention span of eight seconds, less than a goldfish.  This is not true, but that doesn’t stop hundreds of so-called experts from regularly reporting that fiction as fact.  (It was based on a study of how long people spend on a web site, on average, not on a real measure of anything like attention span.)

Other studies claim that the average person receives somewhere between 5,000 and 20,000 marketing messages per day.  I’m not sure what the real number is, but let’s agree that it’s a lot.

In short, our brains are already overstretched in the modern world, and, seen in that light, forgetting is as important for survival as remembering.

The problem is, as an advertising genius said long ago in another context, which 50 percent of everything you hear or see or are subjected to should you forget?  Knowing what’s essential to remember for modern life and success is a much harder puzzle than the acts of remembering and forgetting themselves.

Understood in this context, forgetting as much as you remember is a mercy and a necessity for survival in our information-rich modern world.  More than that, helping people forget the right things becomes an important job in a world like the one we inhabit now.

So speakers take heart.  By putting new ideas into the heads of your audience (and thus forcing them to forget old ideas) you’re helping clean the cerebral house, a highly important task given the speed and volume of new ideas.

Don’t apologize for giving your audience something new.  Every idea you give them scrubs an old one from their brains.  We audiences need to be the sharks of the information age, moving forward in order to keep up and to keep ingesting new thoughts while jettisoning the old.

Help your audiences forget – the right things.

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