以色列科學(xué)家研究發(fā)現(xiàn),，無論對孩子還是成人來說,，有氣味的物體會在他們的大腦中留下鮮明的印記，這就是為什么氣味往往能勾起回憶的原因,。
以色列魏茨曼科學(xué)研究所的雅拉·耶舒?zhèn)惖热嗽谛乱黄诿绹懂?dāng)代生物學(xué)》雜志上發(fā)表論文說,，無論香味還是臭味，大腦都能“銘刻”最初的記憶,，但這種記憶僅限于氣味,。
為測試與氣味有關(guān)的記憶，科學(xué)家向一組自愿接受測試的人展示了一些物品,，這些物品或能發(fā)出氣味,，或能發(fā)出聲音，其中有些物品的氣味或聲音是令人愉悅的,，如梨和吉他,，還有一些是令人反感的，如死魚和動力鉆。
科學(xué)家利用磁共振成像技術(shù)對被測試者的大腦進(jìn)行掃描,，他們發(fā)現(xiàn),，當(dāng)被測試者遇到可發(fā)出氣味的物體時，大腦海馬區(qū)和扁桃核都會產(chǎn)生明顯反應(yīng),。但遇到可發(fā)出聲音的物體時,，就沒有出現(xiàn)這種現(xiàn)象。一周后再要求他們回憶所遇到的物體,，被測試者大多能回憶起有氣味的物體,，而不是可發(fā)出聲音的物體。
大腦海馬區(qū)對人的學(xué)習(xí),、記憶能力等有重要作用,，而扁桃核是大腦控制情緒的中心。這兩個部位有反應(yīng),，表明大腦對與氣味有關(guān)的物體更敏感,。
科學(xué)家稱，此項研究成果有可能幫助人們找到改善記憶力甚至治療早期腦部創(chuàng)傷的新途徑,。（生物谷Bioon.com）
生物谷推薦原始出處：
Current Biology, 09 November 2009 doi:10.1016/j.cub.2009.09.066
The Privileged Brain Representation of First Olfactory Associations
Yaara Yeshurun1, , , Hadas Lapid1, Yadin Dudai1 and Noam Sobel1
1 Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel
Authors [1], poets [2], and scientists [3,4,5,6] have been fascinated by the strength of childhood olfactory memories. Indeed, in long-term memory, the first odor-to-object association was stronger than subsequent associations of the same odor with other objects [7]. Here we tested the hypothesis that first odor associations enjoy a privileged brain representation. Because emotion impacts memory [8,9,10], we further asked whether the pleasantness of an odor would influence such a representation. On day 1, we associated the same visual objects initially with one, and subsequently with a second, set of pleasant and unpleasant olfactory and auditory stimuli. One week later, we presented the same visual objects and tested odor-associative memory concurrent with functional magnetic resonance brain imaging. We found that the power (% remembered) of early associations was enhanced when they were unpleasant, regardless of whether they were olfactory or auditory. Brain imaging, however, revealed a unique hippocampal activation for early olfactory but not auditory associations, regardless of whether they were pleasant or unpleasant. Activity within the hippocampus on day 1 predicted the olfactory but not auditory associations that would be remembered one week later. These findings confirmed the hypothesis of a privileged brain representation for first olfactory associations.
