So how is your memory? Pretty good? Did you watch the debate last Thursday night? The relatively genteel Canadian one, not the three-ring circus on the American network that attempted to pass as political discourse. What do you remember? Not that memorable? I suspect that’s the answer for most people. How important will the debate be when you come to make a decision on which box to check on October 19? Chances are, you answered, “Not very” to that one. Here’s the catch: you are very likely wrong about that.

Our minds are complex things. The best research doesn’t take us very far in unraveling the mysteries of what goes on between our ears. We have a lot still to learn about how things work in there. But researchers have generated a fairly substantial list of things we feel fairly certain about. And one of them is that bad news is a lot more powerful than its warm fuzzy cousin, good news. When we hear something negative, it sticks with us a lot longer than the nice things people have to say. A lot longer.

This bias towards negative information has been identified for quite some time. And a variety of researchers have taken a look at the the various implications of this bias. Generally, it seems this habit of our brains is in place to keep us out of trouble. If we hear a lot about a dangerous part of town, we pay attention and hold onto that information because it can help keep us safer. Think of your own city. You can probably readily identify an area or two you would normally steer clear of after dark. But here is a tougher question: what neighbourhood or intersection in your city is the least dangerous? This is a much tougher question and generally only answerable by people who are exposed to this kind of information regularly (think police officers or news reporters or real estate agents).

The bias towards negative information is strong. Numerous studies have tried to put a number on how much more important negative information is to our decision-making. The general consensus is that, without realizing we are doing it, we put 3-5 times as much weight on negative information as we do on positive. So negative information is tough to overcome. But our brain’s game of playing favourites with information goes much further than that.

Not only do we place much more stock in negative information, we quickly forget where we heard it. A few weeks after we learn something, we start to lose track of where, exactly, we learned it. It’s called the sleeper effect. Fifteen years ago, a couple of researchers named Lariscy and Tinkham set out to test the sleeper effect using negative political advertising to see if there was any way to counter-act it. The short version: they couldn’t. They gave their test volunteers good news about an individual first and let it sink in. Then, a short time later, they followed it with bad news about the person (PR experts will recognize this as a version of the classic “get out in front of it” scenario). At first, the good news seemed to help dampen the blow. But fast-forward a few weeks, and the moderating effect was gone. The volunteers had forgotten the good information but remembered the bad. Even more interestingly, they had largely forgotten the exact context of that information (who had delivered it, what they said exactly). And, most alarmingly, their evaluations of the subject were worse than they were when they were first tested. With no additional information to sway those evaluations.

For anyone still following the bouncing ball, the problem here should be coming into focus. That debate you watched? The images and words you consumed are bouncing around in your head. They have made an impression that you may not even be aware of. But what is much more certain, is those words and images will go on influencing you long after you’ve forgotten the details. And the negative stuff is going to have the most influence. Even worse? You are going to forget, precisely, who said it in the first place. So you can forget about blowback. You may be annoyed with the messenger for a week or two, but eventually you will forgive and forget.

For a project as ambitious as electoral representative democracy, this all presents a serious challenge. Politicians, with enough time, research and money, can lob a steady barrage of attacks at their opponents and, more than likely, get off scot-free. Over time, these attacks will steep like a pot of strong tea and begin waging a full-scale assault on any positive impressions a voter might have bouncing around in there. This presents a challenge to any self-professed, fair-minded voter. How can you be certain that you are picking candidate ‘A’ for the “right” reasons? Has your judgement been clouded by ads portraying your former favourite as a dissolute, rudderless lightweight? (Any resemblance to any candidate, living or dead, is purely coincidental). Likely. Is it influencing your ballot box choice? Also very likely. Enough to make you vote for someone else? Quite possibly.

Of course, decision-making is not this simple. There are a lot of factors involved. But decades of research suggests there is little doubt that the barrage of negativity we are going to experience over the next several weeks is not going to make it any easier to make a good decision about who will get to participate in making our laws for the next few years.