Scientists have linked higher intelligence to an appreciation of dark humour, based on a small study that investigated the complex information-processing that's involved in interpreting a sick joke.

But a higher IQ isn't the only thing that'll have you winning popularity contests in your local Louie Appreciation Society - the study also found that those who were most in tune with dark humour had the lowest scores for aggression and bad mood.

"These findings support the notion that humour processing depends on cognitive as well as emotional aspects, and suggest that this also accounts for black humour processing, which seems to be a complex information-processing task," the team from the Medical University of Vienna in Austria concludes.

The researchers recruit 156 male and female volunteers with an average age of 33, and asked them to rate their comprehension and enjoyment of 12 dark humour cartoons taken from The Black Book by German cartoonist Uli Stein.

To give you an idea of the kind of thing the participants were looking at, one of the cartoons is set in a morgue, where a physician lifts the sheet off a body for a woman to identify.

"Sure, that's my husband," she says, "anyway, which washing powder did you use to get that so white?"

Another cartoon depicts a confused man using a public telephone, and the voice coming from the phone says: "Here is the answering machine of the self-help association for Alzheimer patients. If you still remember your topic, please speak after the tone."

Topics ranged from death, disease and deformity, to disability and warfare.

For each cartoon, the participants were asked to rate various qualities, such as how vulgar or tasteless they found it, how fitting was the punchline, how much did you like the joke, and how fresh or novel did you find it?

They were also tested for various qualities themselves, including verbal and non-verbal IQ, mood disturbance, aggression, and educational background.

The team found that there was no difference between the male and female subjects regarding dark humour appreciation, and age didn't appear to be a factor either.

But they did identify three distinct 'groups' in the 156 participants, based on their respective scores:

  1. Moderate black humour comprehension and preference, average non-verbal and verbal intelligence, low values in mood disturbances, and moderate values in aggressiveness
  2. Moderate black humour comprehension and low black humour preference, average non-verbal and verbal intelligence, high values in mood disturbances and high values in aggressiveness
  3. High black humour comprehension and preference, high non-verbal and verbal intelligence, no mood disturbances, and low values in aggressiveness.

To be clear, the study is a small one, with a very limited sample size and a reliance on self-reporting by the participants, so there are some significant limitations here.

The study also only identifies a link between intelligence, low aggression, and dark humour, and does not investigate a causal link between the two - as in, why would these three qualities be linked?

But they do offer up some hypotheses.

As Jamie Doward explains for The Guardian, the researchers suggest that being able to appreciate dark humour was a "complex information-processing task" that not only required higher intelligence, but also a clear mind.

"[N]egative moods and high aggression levels could cloud people's ability to get the joke," says Doward.

In addition to this, the results suggest that if you're unhappy, rather than revelling in the misfortune of others in sick jokes or dark cartoons, you struggle to engage with the humour.

"[I]t could be shown that subjects who are in a bad mood are most likely to dislike black humour, and show lower values with respect to black humour comprehension than subjects who show low mood disturbance," the researchers report.

"These results support studies which show that subjective humour response is influenced by pre-existing mood, as well as the notion that bad mood impairs the involvement in humour, rather than facilitating the appreciation of aggressive humour."

The same could go for aggression - if you have aggressive feelings towards others, it would make sense that you'd enjoy a sick joke, but the results of the study showed the opposite. 

Perhaps getting a good lot in life gives you the luxury of basking in some dark humour.

"Seemingly, only those subjects who have no aggressive feelings towards others, as well as no mood disturbance such as dysphoric or depressive mood, can afford or get away with the playful exposure in the course of black humour processing," the team suggests.

"Another hypothesis would be that aggressiveness as well as bad mood could lead to a reduced information-processing capacity with respect to cognitively demanding humorous contents."

It hasn't always been the case that scientists think low aggression is linked to humour - Freud himself hypothesised that humour gives you a safe, socially acceptable release of repressed sexual and aggressive urges.

"This [study] fits with past research showing that sense of humour correlates with IQ, but refutes the somewhat commonly-held belief that people who like black humour tend to be grumpy and perhaps a little prone to sadism," Christian Jarrett from the British Psychological Society Research Digest explains.

Again, given the limitations of the study, we should take the findings with a grain of salt, but the results are part of a wider trend that's been developing in recent research that suggests those with higher intelligence are better equipped to enjoy complex humour and the more 'rebellious' aspects of language. 

Back in 2015, a separate study linked the propensity to swear and curse with better vocabularies, and in 2011, researchers from the University of New Mexico found that verbal and non-verbal intelligence predicted an ability to process humour.

"A good sense of humour is sexually attractive, perhaps because it reveals intelligence, creativity, and other 'good genes' or 'good parent' traits," they concluded. 

"These results suggest that the human sense of humour evolved at least partly through sexual selection as an intelligence-indicator."

So don't feel bad if you enjoy a sick joke now and again, but just remember - honour the 'too soon' rule if you don't want to get yourself in trouble.

The study has been published in Cognitive Processing.