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Does Intelligence Influence Toxic Behaviour?

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Connection between intelligence and toxic behaviours

Does cognitive ability influence positive and negative behaviour?

Does cognitive ability effect the degree to which we see negative and positive behaviours at work? The answer is yes, research shows that there is a relationship between toxic behaviour and intelligence.

Employees with high cognitive ability are better at self-managing feelings of violence, anger, or frustration.

Read on to learn more about the connection between intelligence and bad behaviour

The relationship between intelligence and counterproductive behaviours

Watch the video to understand how intelligence affects our tendency towards violence and other harmful behaviours, and why intelligent people can self-manage better and end up earning more, on average.

Watch the next video in this series here:

Part 4 – Integrity Testing and Screening

And watch the previous video here:

Part 2 – Does Genetics Play a Role in Toxic Behaviour?

And if you know of anyone who would benefit from this video, please share it with them.

Video Transcript

Hi, Andrew from SACS. Welcome to video number three in our 11 video series on toxic behaviours at work.

This one is about cognitive ability, IQ, aptitudes, whatever you want to call it, intelligence and toxic behaviours.

So we’re really addressing the question of whether cognitive ability can affect the degree to which we see negative and positive behaviours at work.

And the answer is yes, there is a relationship between negative behaviours and cognitive ability.

And so let me show you some research that demonstrates this.

Prisoners and cognitive ability

The first study that we want to show you (refer to video) is from the link between cognitive ability in prisoners.

So this research was undertaken by Brie Diamond and colleagues in the United States of America.

Now, if you go to jail into the States, it may surprise you to know that in many places, they actually psych test you, they might measure your cognitive ability.

In other words, give you an IQ test and intelligence test.

They might test your personality, and they retain those records.

Brie Diamond got access to those records. And what she identified was that certain jail cells were low IQ, medium IQ, or high IQ largely due to pure fluke. In other words, if you get a certain bunch of prisoners together, if you get enough of them randomised across all different jail cells, then by pure luck, you’ll end up with high IQ jail cells, low IQ jail cells, and medium IQ jail cells.

And so the prisoners in there, on average, when you average their cognitive ability that was low, medium, or high, and what you discovered is that the rates of violence corresponded quite closely to the levels of cognitive ability.

So the degree to which they were likely to beat each other up was increased if the level of cognitive ability in that cell block was lowest.

So this is one of the big and important studies in a really practical setting jail, after all, about what determined levels of cognitive ability.

But that’s not the only evidence about the relationship between cognitive ability and violence or toxic behaviours.

IQ and the workforce population

Work populations around the world. And this is the work of Deniz Ones, the famous researcher into negative behaviours across the world.

She found a 0.35 correlation between cognitive ability and negative behaviours in employees generally.

So counterproductive work behaviours as they’re known. So the counterproductive work behaviours which apply in a workplace are really have two types, bad stuff against your colleagues or bad stuff against the organisation.

And what she found was that this correlated 0.35, which is not an inconsequential correlation in big samples with cognitive ability.

So if you’ve got a low IQ workforce, then it’s much more likely that you’ll see negative behaviours out of that workforce.

Flynn effect

The next one is about a thing called the Flynn effect.

Now, the idea of the Flynn effect, this was discovered by a scientist by the name of Flynn from New Zealand, a cognitive ability theorist if you want to put it that way.

He noticed that cognitive ability was improving over the years.

Now, so if you looked at the average levels of cognitive ability for people today versus let’s say 60 years ago, many more people would’ve been considered to be subnormal if you want to put it that way or struggling with their cognitive ability 60 years ago than are now. So cognitive abilities have been improving.

You may also be interested to know that in terms of levels of violence across the world, violence has been reducing across the world for decades, centuries as a matter of fact.

And if you read the press, you would think that this weren’t the case that the world’s becoming more violent, well, in fact, on average, yes, and I know that there are wars and things, but if you go back to let’s say the early 1800s, there were wars everywhere. And so levels of violence have reduced.

Now, it’s theorised that one of the things that might be causing this is the Flynn effect where levels of cognitive of ability have improved. And so therefore, the tendency to violence reduces.

By the way, in the last few years, there’s been evidence of thing called the negative Flynn effect where the levels of cognitive ability are now starting to drop off.

And that’s positive to be largely due to the fact that we are now outsourcing a whole bunch of our brain function to computers.

So we don’t have to do the stuff that we used to have to do.

And so we’re not exercising our brain so much.

And yes, for the first time in human history, cognitive ability, IQ points seem to be declining and that’s been reported widely across the world.

What would be interesting to see is that, if that trend continues where the violence starts to arc back up again and we set out to see more violent behaviour.

Relationship between IQ and remuneration

Now, I just want to finish this section with something that can be considered to be a little controversial, but on the other hand, it is irrefutable. So it has that benefit.

What you’re seeing here (refer to video) is a diagram of the relationship between cognitive ability and income.

And what you see is that cognitive ability correlates quite heavily with income.

So this is the lowest cognitive ability, the lowest decile of cognitive ability.

And this is based on many, many people, so thousands and thousands of people across the United States of America, and the highest cognitive ability is correlated with the highest income.

The interesting thing about that, though, is that if you think of this in a population sense, let’s say you’re in an organisation that employs 10,000 people.

If you think of the 10% of your workforce that’s most lowly paid, you would have to presume that that’s where you’re going to get the bulk of your negative behaviours.

Lowly paid workforces tend to have lower levels of cognitive ability.

So what they will mean is that you’re going to get more negative behaviours out of those workforces.

And of course, this is how it plays out in practise, but it’s a reason that it plays out in practise.

Now, please understand at an individual level, this does not apply.

So you can have a person who has individually low cognitive ability and may be the sweetest, most harmless individual on planet earth.

And you’ll get somebody who’s really smart and evil.

And so yes, at an individual level, that’s true. But if you get large groups of people, on average, you’ll find that you get more negative behaviours.


Why? Well, there is research evidence, genetic evidence that people with higher cognitive ability have better self-management.

Let’s say I get angry at you if I have higher cognitive ability, it seems that I’m better able to manage that and maybe find a sensible alternative rather than to get involved in violence.

In any event, it’s a strong finding from across the world.

The next video is all about a thing called integrity testing, how you can screen for toxic behaviour by asking people what are called integrity questions.

Now, I don’t particularly like the term integrity testing. We tend to call it counterproductive work behaviour testing but it is very effective in helping you to avoid recruiting people who have toxic behaviours.

Join us for the next video to find out what it is and how it works.

Watch the next video in this series to find out more about dealing with toxic employees:

Part 4 – Integrity Testing and Screening

And watch the previous video here:

Part 2 – Does Genetics Play a Role in Toxic Behaviour?

And if you’d like some help screening future hires for toxic behaviour, contact us about our Psychometric Assessment Tools.

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