Not nice to listen to. But what makes such noises unbearable?
这听起来很不悦耳。是什么让这些声音听起来如此刺耳?
Part of the answer is that the brain appears to be hardwired to be alarmed at, for example, alarms and other shrill noises.
一部分原因是大脑似乎天生对某些声音,例如警报声以及其他刺耳的噪音易于产生警觉。
Researchers scanned the brains of 16 participants as they listened to a range of sounds, and asked them to rate the sounds from unpleasant to less unpleasant. Activity in both the auditory cortex and the amygdala varied directly with the subject's ratings.
研究人员让16名受试者聆听各种声音,并扫描他们的大脑活动,然后让他们评价声音的悦耳程度。通过扫描发现杏仁体和听觉皮层的活动与受试者的评价同步变化。
The auditory cortex is where a sound's acoustic features are processed. But it is the amygdala—the small part of the brain in charge of emotional memory—that encodes those features and triggers the negative reaction to unpleasant sounds. And this reaction from the amygdala is delivered back to the cortex making us extremely sensitive (acoustically) to such sounds. This interaction between the auditory cortex and amygdala happens so fast as to seem instant.
听觉皮层是脑中处理声音特征的部分。但负责情绪记忆的是大脑中一个很小的区域——杏仁体,杏仁体能够解密这些特征,并引起对令人不快的声音的消极反应。而且杏仁体的反应会重新传回听觉皮层,这让人们对类似的声音极其敏感。这种听觉皮层和杏仁体之间的互动发生得如此之快,以至于顷刻之间就消失了。
The researchers hope to test this model next with purely pleasurable sounds, as well as other types of negative sounds, including bad words, like [bleep] and [bleep] and [bleep.]
研究人员期望下次测试这种模式时采用美妙的声音,或者其它类型的消极声音,也包括像[bleep]这样的不好的词汇。