Asked to describe your typical internet 'troll', few would have conjured up the image of a Brenda Leyland, a well-to-do middle class mother with her neat bob and Eeyore keyring.
Her death alone in a hotel just a few days after being confronted at her Leicestershire home by Sky News' Martin Brunt, who was armed with a dossier of "trolling" directed at the parents of missing Madeleine McCann, brought into sharp focus how misplaced stereotypical assumptions of "trolls" can be.
In fact, according to at least one expert, Mrs Leyland might not have been a troll at all.
Brenda Leyland, found dead in a hotel, after being confronted about her Twitter activity
Dr Claire Hardaker, a lecturer at Lancaster University and an expert in internet abuse, said that from the tweets she downloaded from Leyland's 'sweepyface' Twitter account, she would not have classified her as a "troll".
"I don't think she was a troll, she had very unpopular opinions, she was convinced that there had been a cover-up and that the British press and police were complicit. She called the McCann's fools, she called someone that she didn't agree with a 'f**ktard,' but that's about as bad as it got.
"She had entirely bought into the conspiracy theory, and she was a campaigner. She was tweeting the Daily Mail, Sky News, the Met Police, everyone to try to get them to investigate. She might have been misguided, but her intentions were to act in the little girl's best interests, and she was obsessive."
One of the most poignant tweets that Leyland sent, Hardaker said, was when she realised Martin Brunt was following her on Twitter. "She actually tweeted him asking him to investigate the theories she was passionate about."
Isabella Sorley, 23, from Newcastle, who tweeted abuse at a feminist campaigner
Hardaker said that it appeared from Leyland's tweets that she had found a "community" through the issue and had taken on a certain importance within that group. "To blow that open can be shattering for someone."
Dr Tomas Chamorro-Premuzic, professor of business psychology at University College London, said that trolling and abuse online had now become so commonplace that it was hard to find common distinguishing features.
"The profile of an internet troll has nothing to do with class, or socio-economic or educational variable. It's more psychological," he said. "One of the characteristics of people who spend of lot of time doing things like this is that they don't seem to have the same ability to do this in the real world. They are often compensating for a lower assertiveness or dominance in the real world, they are a little bit more repressed."
The stereotype of an internet troll, an angry young man sat alone in his room shouting into the ether, did still apply in some cases though, Hardaker said. She cited John Nimmo, a student jailed for trolling the feminist activist Caroline Criado-Perez, Liam Stacey, the 21-year-old who tweeted racist abuse about footballer Fabrice Muamba as he suffered a heart attack on the pitch, and Frank Zimmerman, the agoraphobic prosecuted for abusing former MP Louise Mensch, though as a pensioner he was older than the stereotypical troll.
But Peter Nunn, who was given an 18-week sentence last week for sending abusive messages to MP Stella Creasy, was a father-of-two. Yet his abuse was so bad Creasy had felt driven to install a panic button in her home.
And John Nimmo's co-defendent, Isabella Sorley, as a young woman, did also not fit the mould. Yet in tweets after the successful campaign to get a woman on a banknote, she told Criado-Perez "go kill yourself" and "rape is the last of your worries". Later, Sorley expressed regret for having "jumped on a bandwagon".
Blogger Peter Nunn said he sent rape threats to Stella Creasy to 'satirise' online trolling
Chamorro-Premuzic said that he could understand how the kind of confrontation engineered on the television could be shattering for a person who had found "comfort from the anonymity, and from being part of a group".
"People can't cope with it. Confront people in the real world, they're exposed. They can't keep being the civilised and polite self that they are in normal life. It potentially puts a lot of pressure or strain on people," he said.
He added that it was likely that people who did use the internet to provoke and insult were vulnerable, though not all would be. "They might be more impulsive people and have a low sense of control over events. Trolling can be a coping mechanism to release anger and tension, and there's actually an argument to let them do that. But then, they are often upsetting other people by their actions."
"I don't think the way forward is to prosecute or publicly shame people," he added. "I think the way forward to moderate harder online and censor more, within reason."
Frank Zimmerman, an agoraphobic, was prosecuted for sending abuse to Louise Mensch
Psychologists and experts agree there should be a clear distinction drawn between those who direct rape or death threats against individuals, those who deliberate set out to provoke and upset, and those who just tweet passionately on unpopular or conspiracy theory-heavy subjects.
"People have unusual, strong, conspiratorial views online, that are genuinely held," Chamorro-Premuzic said. Not everybody sees the world in the same way, and we should be able to express that view. But more hardcore, traditional trolls will do that only to provoke. They have a sadistic streak, they do it to get a reaction, that's what they care about."
Chamorro-Premuzic said it was sometimes difficult for laymen to tell the difference. "That may have been the problem in this case. But actually, for the most part, the media and the authorities don't really care about the reason why someone is doing it," he said.
"The problem is the effect it has on the victim. If it is wrong, and deeply upsetting to people, then it should be suppressed. It can be very difficult though. The media has a responsibility to minimise the psychological harm that these people can cause to others."