Some antidepressants alter peoples' moral judgement

Some antidepressants alter peoples' moral judgement
( -- The most common type of antidepressants, serotonin enhancers, alters peoples’ moral judgement and leads to a reduction in aggressive behaviour, a study published today in the journal Proceedings of the National Academy of Sciences (PNAS) has found.

The new research, by scientists at the University of Cambridge's Behavioural and Clinical Neuroscience Institute, discovered that healthy volunteers given drugs which increase their serotonin,  (SSRI), have an increased aversion to harming others, viewing such actions as morally forbidden.

Ms Molly Crockett of the Behavioural and Clinical Neuroscience Institute (a Medical Research Council and Wellcome Trust funded initiative) is the lead author of the paper. She said: "Our study suggests that these medications can affect people's sense of right and wrong, which influences the choices they make in everyday life.

"Interestingly, the drug's effects were strongest in people who were naturally high in empathy, suggesting that serotonin could enhance people's concern for others by making the prospect of harming them feel worse."

, which include SSRIs like the one used in the study, are among the most widely prescribed drugs worldwide. In the United States and the UK, an estimated ten per cent of the population take antidepressants for a range of psychiatric and medical conditions.

The Cambridge researchers measured the drug's effects on moral judgement by giving the participants 'dilemmas' which pitted beneficial outcomes (e.g., saving five lives) against highly unpleasant harmful actions (e.g., killing an innocent person). Individuals with increased serotonin were far more likely to judge the harmful actions as morally wrong even when such actions would result in significant benefits.

The participants' aversion to harming others, on the grounds that it was morally objectionable, was also apparent on a different test in which subjects decide whether to accept or reject fair or unfair splits of a sum of money from another player. People tend to reject unfair offers as an act of retaliation, because rejecting offers harms the other player financially. Subjects taking the SSRI were less likely to reject unfair offers, possibly because they were reluctant to hurt the other players financially.

A previous study by the same research group had found that decreasing serotonin made people more likely to retaliate against unfairness. 

Citation: Some antidepressants alter peoples' moral judgement (2010, September 28) retrieved 24 May 2019 from
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Sep 28, 2010
It could be said that people are depressed because other people or life itself has treated them badly, and they cannot retaliate. Part of SSRIs' efficiency may be because they diminish the urge to retaliate. In other words, if you can't do something, you're better off not wanting it.

This, of course has its downsides, too. Pick on somebody until they start eating SSRIs, and there's even less of a chance they'll ever get even. Now even others dare to pick on them.

Sep 28, 2010
I agree with the conclusions of this study and cannot state how overwhelmingly this needed to be done and address. And the statement that it seems to effect people how naturally have high empathy is so totally true.

I will not go into the details of what I watched a friend go through - but they changed back to 'normal' without the anti depressants and they had to learn better coping skills. But their actions while on antidepressants was deplorable, and almost childlike in their way of justifing them.

I have seen a lot of people on these antidepressants and while they are calm - or just nolonger moody many take something to extreme that is not healty or even legal in many cases.

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