子长天气预报15天查询:我们只使用了大脑的10%？

Is it true that we use only 10% of our brain?

Published on June 21, 2011 by Ezequiel Morsella in Consciousness and the Brain

It is quite remarkable that a handful of ideas from the field of neuroscience spread like wildfire through the popular media, thereby becoming part of our culture and worldview, while other ideas remain neglected, known only to a small group of experts. A recent example would be the idea of mirror neurons, which has successfully stimulated the curiosity of many people outside the ivory tower. Why some ideas are more catchy than others remains a mystery.

 　　有这样一种现象非常值得注意：一小部分神经科学领域的观念通过大众传媒不胫而走，并因此成为我们文化和世界观的一部分，而另外一些观念却依旧被忽略，仅被一小群专家所知晓。近期的一个例子就是镜像神经元的观念。这个观念成功的引起了象牙塔外很多人的好奇心。为什么某些观念会比其它理念更引人注目？这依然是一个谜。

Since I was little, I always heard that humans use only 10% of their brains.  To me, this idea agreed with the age-old notion that we as humans have great potential. Years later, I learned from reading a series of excellent books on the history of neuroscience and psychology that this notion may actually be a misinterpretation of the classic research by the great Wilder Penfield (1891-1976), an American born neurosurgeon who was the first director of the world-famous Montreal Neurological Institute of McGill University. Because of his many contributions to medical research in Canada, Penfield was regarded at one time as "the greatest living Canadian." Today, he is remembered as one of the all-time greatest thinkers about the brain.

Penfield pioneered a technique for the treatment of severe epilepsy which required damaging the brain areas responsible for the onset of the seizures. One obvious concern in carrying out this procedure is that the surgeon may be damaging a brain area that is critical for the welfare of the patient. Penfield devised a technique to assess whether the area to be damaged was critical for brain function. While the patient was awake (there are no pain receptors in the brain, so neurosurgery can be carried out painlessly while patients are conscious), Penfield would mildly stimulate the targeted brain area with an electrode and would note the effects of the stimulation. With this technique, which continues to be used today, the surgeon can evaluate whether the electrical stimulation leads to something notable (e.g., a visual hallucination, auditory hallucination, or movement of a finger) or whether the stimulation disrupts function (e.g., the patient can no longer utter a word). Either kind of effect suggests that the region being stimulated should not be damaged. 

　　 Penfield开创了一种治疗严重的癫痫的技术。这种技术通过损毁负责惊厥发作的大脑区域来实现。采取这种治疗方法的一个明显的问题是，医生可能会损害到对患者来说至关重要的大脑区域。Penfield发明了一种用以评估待损毁区域对于脑功能是否关键的方法。在患者保持清醒时候（由于大脑中没有疼痛受体，使得神经外科手术可以在患者有意识的情况下无痛苦的实施），Penfield使用电极轻微的刺激特定的大脑区域，并记录下刺激的效果。采用这种沿用至今的技术，外科医生能够评价电刺激是否会导致明显的反应（如幻视，幻听，或手指运动），或者电刺激是否会破坏某些功能（例如，病人无法发声）。无论出现上述两种情况中的那一种，都表明受到刺激的区域不应该被损毁。 

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From this technique, Penfield and his colleagues discovered (among many things) the topography of the motor strip in the motor cortex and the nature of the adjacent somatosensory 'homunculus.'

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In one famous example, a female patient reported that stimulation led to a vivid experience in which she was enjoying the sights and sounds of a concert at Royal Albert Hall in London. Penfield was surprised that the patient felt as if she were at the concert while also knowing that she was in the operating room. He referred to this as "double consciousness," because the subjective experience of the patient was about two separate places. Penfield and others noted that the stimulation of few areas (circa 10%) led to a detectable effect  (e.g., the activation or disruption of a perceptual or motor event).

 　　在一个著名的实验中，一位女性患者宣称电刺激导致她产生了一种仿佛正在享受一场在伦敦皇家阿尔伯特音乐厅举办的音乐会中的场景和声音的鲜活体验。对于患者在能感到她仿佛身处音乐会的同时也清楚地知道她其实是在手术室，彭菲尔德感到很惊讶。他将患者的这种身处两个不同的地方的主观体验称为“双重意识”。彭菲尔德和其他人指出，大约只有10%的大脑区域被刺激后会产生明显的效果（如某种感知或者运动的激活或丧失）。undefined

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What I learned from the historical record is that it was this observation that led to the incorrect view that humans use only 10% of their brains. In truth, many areas that lead to no effect when stimulated by electrode are important "association areas" that connect other areas of the brain, permitting communication between two brain regions. Such interaction between areas is notable in the classic McGurk effect, in which what one sees influences what one hears. (Clickhere for a dramatic demonstration.) Areas whose stimulation leads to no discernible effect may also consist of networks whose function is not directly perceptual, mnemonic, or motor.

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The historical record leads one to believe that the notion that humans use only 10% of our brain is more myth than fact. But this is not to say that we are not creatures of tremendous potential. Consider space flight, the Sistine Chapel, or the pioneering research of Wilder Penfield.

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