You can't have missed the latest Twitter debacle. Some deeply unpleasant individuals got very angry at women pursuing pro-female agendas publicly. People then got very angry at these individuals who were sending threats and at Twitter in general for not doing more to stop it. Some people then got angry at these people in turn about the solutions they wanted. A brief twitter-boycott was then organised by a high profile person who seems to make people angry with her I mean their very existence. People then got very angry about the supposed rationale behind this boycott. People then got very angry with these people who were angry about the boycott. There may have been more but it was getting too complex for me. I'm only a neuroscientist.

Around this time, GQ were receiving an onslaught of rage-fuelled messages from One Direction fans, due to innocuous comments made about Harry Styles, one of the bipedal haircuts in the aforementioned band. Then they announced the new Doctor Who and many got angry about him being another white male. That's a major issue for some; not enough racial/gender diversity in Time Lords. Each to their own.

A lot of anger about lately, is what I'm saying. If it were a liquid we'd be piling sandbags against our doors. But where does it all come from? And why is it so often directed at bizarre targets?

Psychologically, it's a complex subject (as many emotions tend to be). Aggression (in humans) is defined by Anderson and Bushman as "any behaviour directed toward another individual that is carried out with the proximate (immediate) intent to cause harm. In addition, the perpetrator must believe the behaviour will cause harm and that the target is motivated to avoid the behaviour". Someone's doing something you don't like (e.g be a woman who expresses opinions), you do something to them which you know will cause harm (e.g. threaten them with violence and assault), and they'll hopefully respond to prevent you doing that again (e.g. stop voicing opinions).

It's important to differentiate anger and aggression. Anger is the state of emotional and physiological arousal. You can get angry about something but opt to not behave aggressively to someone as a result; this sort of behaviour is regarded as rather mature. Similarly, you can be very aggressive to someone, e.g. by mugging them, without being angry at that person; odds are you know nothing about them apart from the fact that they may have valuables on them. For the record, mugging someone is not regarded as mature.

Hostility is the cognitive component of aggression. It's the stuff you think about that leads to aggressive behaviour, and keeps it happening while you're doing it. Hostile aggression is when you react aggressively and impulsively to perceived threat/insult. Conversely, instrumental aggression is when you use aggression to acquire more long term goals. A co-worker who openly belittles you in front of others is likely using instrumental aggression to obtain promotions at your expense; you subsequently attempting to cave his head in with a stapler while he's in the toilet is hostile aggression.

There are numerous theories behind human aggression. Psychodynamic, evolutionary, ethological, the frustration-aggression hypothesis, cue-arousal, social learning and many more. Perhaps the most comprehensive take is the general aggression model. Neuroscientificallly, aggression is believed to involve the frontal lobes, the amygdala and serotonin, but the overall understanding of it seems limited. This is understandable; to scientifically study anger you'd need people to get angry. However, most psychological experiments on humans require ethical approval, and actively harming/angering people is unlikely to get that. On the Venn-diagram of "people easily angered" and "people who willingly volunteer to let scientists poke and prod them" there's not going to be much overlap, so opportunities for research are limited.

But another interesting question is why people seem so angry about relatively inconsequential things so often these days. One possibility is that it's been hot lately, and people are more aggressive when it's hot. What with climate change, maybe we can expect more of this?

The frustration-aggression hypothesis says we get angry when frustrated; when our desires, goals or expectations are thwarted. There are so many opportunities for this these days, what with capitalism telling us all the things we could/should have (but can't), the media telling us how terrible everything is with the economy/environment/politics/everything else, and the internet ensuring we have a constant stream of potentially frustrating info, it's easy to see how people could live in a perpetual state of simmering anger. However, it's often difficult to do anything about these frustrations, so it's likely to result in displaced aggression. This is where you can't respond to the thing that's frustrating you due to it being unavailable or, more frustratingly, something or someone who has the greater ability to harm you if you react. The arousal of anger doesn't dissipate quickly, so it's often transferred to less deserving but more convenient targets. Your life isn't going as you'd hoped and your situation sucks? It can't be your fault; it's those damn women and feminists, ruining society and screwing you over in the process. But thanks to the internet, you now have ample opportunity to get your "revenge".

That's one thing the internet does do well; it provides ample things for us to get angry about that we've power to change or affect, but it does offer us plenty of avenues to displace and vent our aggression and anger at more minor, less significant targets.

Obviously the truth of the matter is way more complex, taking in societal, evolutionary and psychological factors beyond the scope of a single blog post. And anger and aggression are not all bad. Without anger, serious injustices would go unanswered, we would be less motivated to protect ourselves and our loved ones and may not have survived as a species, and the Daily Mail web traffic would collapse like a rice-paper canoe.

But anger and aggression are all too easy to fall victim to, and often over the most insubstantial of reasons when you think about it, which is rarely of benefit to anyone. After all, it was Sigmund Freud who said "Anger leads to fear, fear leads to hate, and hate leads to the dark side".

And if that last line doesn't anger a large number of people, I'll be very surprised.

Dean Burnett is a veritable ray of sunshine on Twitter, @garwboy

He also does a very soothing podcast with his friend and co-blogger Dave Steele.