研究:人類疼痛感乃心理作用

According to scientists from Oxford, Cambridge and two German universities, positive thoughts can double a painkiller's effect while negative thoughts can cancel them out, which may prove that pain actually is all in the mind. The research is published in the journal Science Translational Medicine.

英國牛津大學、劍橋大學以及兩所德國大學的科學家今日宣稱，病人情緒積極向上能夠讓止痛藥的效果加倍，而消極低沉則會讓止痛藥毫無作用，從而很可能證明了一種看法，即：疼痛乃心理作用。研究論文已被刊登在了醫學雜誌《轉化醫學》上面。

In the study, 22 volunteers had a pain device put on their skin that was too hot for comfort. Each then had an intravenous line attached to deliver a painkiller. They were asked to rate the pain before any painkiller was introduced. The average score was 66.

研究中，22名受試者均被安裝了疼痛裝置，使得他們的皮膚產生灼痛感。隨後每人都被插入靜脈注射管以輸入止痛藥。在藥物輸入之前，研究人員調查他們的疼痛程度，得到的疼痛平均指數爲66。

Then the researchers started providing the painkiller, without telling the volunteers they had done so. The average score dropped to 55. But when the scientists told them they had started administering the painkiller the score dropped again to 39. When they said they had stopped providing the painkiller, the score rose to 64 - even though the opiate was still flowing.

接下來研究人員在不告知受試者的情況下輸入止痛藥，疼痛平均指數下降到了55。但在科學家告知受試者止痛藥正被輸入他們體內後，疼痛指數下跌至39。而在宣稱停止輸入止痛藥後，疼痛指數又上升至64，而事實上藥物輸入過程並沒有間斷。

At the same time the volunteers' brain activity was monitored using MRI scans. These showed their brains' pain networks were more active when they thought the drug was not being administered. Professor Irene Tracey of Oxford University, who led the research, said: "Doctors shouldn't underestimate the significant influence that patients' negative expectations can have on outcome."

與此同時，研究人員還對受試者的腦部活動進行了MRI掃描。掃描結果顯示，受試者以爲自己沒有被輸入止痛藥時，大腦的痛覺神經系統更爲活躍。領導該研究的牛津大學教授艾琳稱：“病人的負面預期會產生某種藥理結果，大夫們不應忽視這種影響。”