EVER wonder why you come away with a sense of exhilaration after a hard day of trolling the internet?

It could be because you're drunk with power.

A new study has found that anonymity gives people the same feeling of abandon as power and alcohol intoxication.

Researchers at Northwestern University in the US found that all three states led to extreme behaviour — both good and bad.

"Although these pathways appear to be unrelated on the surface, they all lead to disinhibited states through a common psychological and neurological mechanism," said Jacob Hirsh of the university's Kellogg School of Management.

Dr Hirsh's colleague Professor Adam Galinsky said the loss of inhibition led to "significant behavioural consequences".

However, the study found that those consequences weren't always the same.

When people lose their inhibitions, they often behave in a manner more consistent with their true motives or character. At the same time, they also tend to be more easily influenced by their environment.

"In effect, disinhibition can both reveal and shape the person, as contradictory as that may sound," Professor Galinsky said.

The end result is that power, alcohol and anonymity can all inspire either strong pro- or anti-social sentiments in people.

The study may help explain why anonymous commentators on the web often appear to hold extreme views.

Dr Darryl Cross, a psychologist at Crossways Consulting, said many people believed there were no repercussions for their actions online.

"It's the fact that they're not confronted visually with another person," he told news.com.au.

"People believe the myth that they can say things that ordinarily they wouldn't be able to say just because they are online."

The consequences of web comments posted under the guise of anonymity can be very real. In a landmark case in 2009, supermodel Liskula Cohen won the right to sue an anonymous commenter who called her a "skanky ho" on a blog.

Dr Cross said the vitriolic nature of internet comments was a symptom of something similar to a split personality.

"I think what we have is, people have two personas," he said.

"The first is an in built human instinctual personality and that’s always there for all of us, it's an animal instinctual personality.

"And then there's always the second personality which is the more conservative, the more guarded, the personality is more in perspective.

"What you've got (online) is people who are prepared to let their instinctual personality out rather than really taking a second perspective, looking at it in a different way, and then saying the second thing that comes into their mind instead of the first."

Dr Cross said one way to bring some decorum back to online discussions was to enforce compulsory registration for websites with a comment area.

"Anything that requires personal responsibility has got to be a plus," he said.

"Once they have to register and they're held accountable, then that's really going to be a major step forward."

Failing that, Dr Cross suggested people come up with a litmus test for what was acceptable to say and what wasn't on the web.

"If they think about their grandparents, that might be one way that they can actually consider what they're going to be writing," he said.

"What would your grandma and grandpa say about it?"