It is easy to laugh at footballer Luis Suarez.
He has been punished before for biting opponents. Then, with nothing to gain and all to lose - sponsorships, his reputation and even a chance to continue in the World Cup - he sinks his teeth into an opponent's shoulder.
Madman? Idiot? Or just another person who succumbs to violent urges, even when his rational mind would tell him that his actions are more likely to hurt him than anyone else.
There are more Suarezes around than you may think. You see them at the workplace and in street-soccer courts - otherwise intelligent people who can't control their impulses.
Psychiatrist Ang Yong Guan told My Paper that he recently had a patient with violent urges.
"He thought that someone was talking bad about him and, just based on that, he went to push the person," he said.
On another occasion, the same man tried to flip a table.
What makes these people flip, figuratively, when what they stand to lose is even more than the satisfaction gained from their actions?
"The logical part of the brain is completely shut off when the emotions are (running) so high," said sports psychologist Jay-Lee Longbottom, who is in private practice.
Suarez, a Liverpool striker, has become the butt of jokes, but his situation may not be all that funny.
The Uruguayan was hit with a four-month ban from all football yesterday for biting defender Giorgio Chiellini during a World Cup match against Italy.
Last year, he was banned for 10 matches for biting Chelsea defender Branislav Ivanovic. In 2010, he bit a certain Otman Bakkal and was punished.
Another sports psychologist, Edgar Tham, said: "Some may even suggest that his most recent aggressive act was already hardwired - meaning that it may have already become a habit."
Ms Longbottom, who worked at the Singapore Sports School for two years, said that such aggression among sportsmen shows a need to regain domination after being challenged.
"Usually, it has everything to do with the culprit's perception of his performance and role in the match," she said.
Child psychiatrist Brian Yeo said that children may bite others when they are angry, as they are not very expressive verbally, but "there is no excuse" for an adult to do it.
Dr Ang thinks that a personality disorder could be to blame.
"They may be insecure and threatened very easily. They think they must win all the time," he said.
Such people may take even a tackle as a personal slight. "They are acting on a primitive part of their brain," Ms Longbottom said.
Counselling and working on controlling one's emotions may help. And Suarez may have time on his hands to fix his teething problem. But he's not alone in hurting himself and others, and he may be in need of help.
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