Murdoch University-led research has found that social interaction is a key mechanism in individuals radicalising into extremists.
Lead researcher Dr Emma Thomas said the study provides evidence that the radicalisation process requires two elements: 'prompts' from others supporting the idea that only radical action can achieve change; and social interaction.
"Over the past decade, investigators have confronted the fact that very little evidence exists to support the idea that political extremism is caused by psychopathology," Dr Thomas said.
"While the media continues to use words such as 'madmen', 'crazed' or 'deluded' to describe those who undertake radical actions, more objectively, these people behave in ways that are strategic and designed to affect change in society.
"That they use radical action indicates that they feel conventional ways of seeking change, such as legal action or protest, won't work. But people don't become extremists sitting alone in a room – they require others to test their viewpoints and confirm their beliefs."
To test their theory, researchers measured 114 participants' responses to an anti-caged egg campaign, dividing them into political groups and radical groups.
The political groups were primed with expert commentary saying peaceful action was the best way to stop cruelty to hens, while the radical groups were told more extreme action was needed, even if illegal.
Half of the groups were instructed to fill out questionnaires and behavioural measures immediately after the presentation, while the other half were given 30 minutes to debate the situation before being evaluated.
"As expected, group discussion produced stronger action intentions, greater awareness of shared grievance as well as a belief in the need to involve and convince society, in both political and radical groups," Dr Thomas said.
"However, the radical group went further. They were more willing to support more extreme measures, including supporting groups that rescued chickens from factory farms through break and enter, chaining themselves to farming equipment and donating money to organisations that sometimes acted illegally."
Primed radical groups who discussed the situation were also much more likely to take real action compared to those in the radical group who didn't discuss the campaign (88 per cent to 48 per cent).
"The combination of priming with social interaction created the conditions for more extreme action. Although these participants were not full blown radicals by any means, this research provides evidence that radicalisation is a social, group process," Dr Thomas said.
"Political extremism is not something specific to certain cultural, ethnic or religious groups, nor is it an aspect of individual psychopathology," Dr Thomas said.
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"Social interaction and psychological pathways to political engagement and extremism." Emma F. Thomas, Craig McGarty, Winnifred Louis. European Journal of Social Psychology. Article first published online: 4 OCT 2013 DOI: 10.1002/ejsp.1988