dwòg komen pou depresyon yo ak Parkinson la ka chèf jijman moral moun nan sou mal lòt moun, dapre rechèch ki soulve kesyon etik sou jan pou sèvi a nan dwòg yo.
Etid la te jwenn ke lè moun ki an sante te ba yo yon dòz yon sèl-Off nan yon dwòg serotonin-pou ranfòse lajman sèvi ak trete depresyon yo te vin pi plis pwoteksyon nan lòt moun, peye prèske de fwa lavalè anpeche yo k ap resevwa yon chòk elektrik nan yon eksperyans laboratwa. Yo menm tou yo te vin pi plis ezite ekspoze tèt yo nan doulè.
Syantis yo tou te jwenn ke Dopamine ki ogmante dwòg la Parkinson la, levodopa, te fè moun ki an sante plis egoyis, wiping out the normal tendency to prefer to receive an electric shock themselves, while sparing those around them.
Molly Crockett, a psychologist at the University of Oxford who led the work, said the finding that a single exposure to the drugs had such a noticeable impact on behaviour challenged the idea that we have stable moral values.
“Patients [taking these drugs] are tracked in terms of how their symptoms improve, but not necessarily in terms of how their behaviour changes,"Li te di. “In the treatment of Parkinson’s, some patients go on to develop compulsive gambling and compulsive sexual behaviour. The drugs have consequences that reach out into the world beyond the patient.”
She added that it was unclear whether the effects seen in the study would be replicated in patients. An alternative possibility is that the drugs could bring the behaviour of patients “back to baseline” by stabilising their psychological state.
“The central message is we need to have more research into how these drugs affect behaviour, both in healthy people and in people taking them for disorders,"Li te di.
In the study, published in the journal Biyoloji Kouran, 175 participants took part, ak 89 assigned to receive the anti-depressant citalopram or a placebo and 86 given either levodopa or a placebo.
The participants were also randomly designated as “deciders” or “receivers” and anonymously paired up. All participants were given mildly painful electric shocks matched to their pain threshold so that the intensity was not intolerable. Deciders were told that shocks to receivers would be at the receiver’s own pain threshold.
Deciders went into a room alone with a computer terminal, and each took part in around 170 trials. For each trial, they had to choose between different amounts of money for different numbers of shocks, up to a maximum of 20 shocks and £20 per trial. Pou egzanp, they might be offered a choice of 7 shocks for £10 or 10 shocks for £15. Half of the decisions made in the trials related to shocks for themselves and half to shocks for the receiver, but regardless of who received the shocks, the deciders would get the money.
nan mwayèn, people given a placebo were prepared to pay around 35p per shock to prevent harm to themselves and 44p per shock to prevent harm to others. Those on citalopram, the seratonin-based drug, were far more harm-averse, willing to pay an average 60p per shock to prevent harm to themselves and 73p per shock to prevent harm to others. Tout, they delivered around 30 fewer shocks to themselves and 35 fewer shocks to others than those on placebo.
People given levodopa, sepandan, were not willing to pay any more to prevent shocks to others than to prevent shocks to themselves. nan mwayèn, they were prepared to pay approximately 35p per shock to prevent harm to themselves or others, meaning they delivered on average 10 more shocks to others during the experiment than the placebo group.
“The dopamine drug made people more selfish,” said Crockett. “Most people show this pattern where they think it’s worse to harm other people than to harm oneself. That’s abolished by the drug.”
The researchers suggest that in future it may be possible to give people a simple test to assess whether their decision-making behaviour has been radically altered by a drug, as well as asking them about whether their mood and symptoms have improved.
“We’re not transforming someone from a healthy person into a criminal or anything like that,” Crockett said. “But in aggregate we make decisions multiple times a day and they can shape our lives.”
- This article was amended on Friday 3 Jiyè. It had mistakenly been illustrated with a photograph of ecstasy tablets. This picture has been changed.
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