科學家稱大腦會“占卜” 每個人都是預言家
People subconsciously make thousands of tiny predictions each day, e.g., when a bus will arrive, who is knocking on the door or if a dropped glass will break。
Researchers at Washington University in St Louis focused on the mid-brain dopamine system (MDS)， which provides signals to the rest of the brain when unexpected events occur。
The scientists tested healthy young volunteers who were shown films of everyday events. And then it was stopped. Participants were then asked to predict what would happen five seconds later。
Half of the time, the movie was stopped just before an event boundary, when a new event was just about to start. The other half of the time, the film was stopped in the middle of an event。
The researchers found that participants were more than 90 percent correct in predicting activity within the event, but less than 80 percent correct in predicting across the event boundary. They were also less confident in their predictions。
Using functional MRI (FMRI)， researchers found that this system encodes prediction error when participants made prediction. And they saw significant activity in several mid-brain regions, among them the substantial nigra, which is the part of the brain most affected by Parkinson's disease, and is important for controlling movement and making adaptive decisions。
Lead researcher Jeffrey Zacks said: "Successful predictions are associated with the subjective experience of a smooth stream of consciousness. But a few times a minute, our predictions come out wrong and then we perceive a break in the stream of consciousness."
The research is published in the Journal of Cognitive Neuroscience。據英國《每日郵報》8月23日報道，人們每天都會在潛意識中做出成百上千個小預測，比如公交什麼時候會來，誰在敲門，或者掉落的杯子是否會破碎。
聖路易斯華盛頓大學的研究人員集中研究了中腦多巴胺系統，該系統在意外事件發生時，會向腦部其他區域發送信號。
科學家對一些身體狀況良好的年輕志願者進行測試，並讓其觀看關於日常生活的影片，然後暫停影片，讓他們預測影片中接下來5秒後會發生什麼。
(影片暫停的情況分爲兩種)，一種是，影片剛好停在事件的分界線上，即一個新事件開始前。另一種是，影片在某事件的中間部分停止。
研究人員發現，90%以上的參與者可以對事件內的活動做出正確的預測，但是，跨事件做出正確預測的人卻不足80%，而參與者在預測的過程中也更不自信。
通過功能核磁共振成像，研究人員發現中腦多巴胺系統在參與者進行預測時，對預測誤差進行了編碼。他們觀測到很多中腦區域會有明顯活動，包括大量的黑質。該物質是人腦中受帕金森氏症影響最大的一部分，它對人類控制行爲並作出適應性決定至關重要。
領導該研究的傑弗裏•扎克斯說：“成功的預測與流暢的意識流主觀活動有關，但是，當預測出現錯誤時，我們就會感知到意識流被打斷。”
該研究發表在《認知神經科學雜誌》上。
