据physorg网站2006年8月2日报道，画家训练过的眼神可以区别常人无法区别的差别；音乐家可以辨别出细微的跑调。大脑研究人员将这种能力称之为感性学习能力。
在研究中获得一次意外发现后，美国麻省理工学院皮库尔学习和记忆研究所研究员和他们研究伙伴们共同合作破解了这一现象的机理。该研究发现将刊登在8月3日出版的《神经元》期刊上。
他们最初是想研究视力丧失对大脑的影响。但是实验中老鼠视力丧失之前，研究人员使用基线测量法进行测量的仪器屏幕上却出现了一种斑纹图案。非常令人感到意外的是，研究人员发现尽管这个图案在观察期没有什么变化，但是在过了仅仅12小时后，老鼠视力越发与这种图案相“协调”。在经过几个观察期后，老鼠大脑中斑纹的反应增强，当老鼠的视力超出正常时斑纹反应达到最强。研究人员将这种变化称之为“刺激选择性反应增强(SRP)”。
皮库尔研究所神经系统科学教授和此项研究的参与者之一马克·比尔说，“刺激选择性反应增强的特性与一些人类感性学习模式有着惊人的相似”。因此，此种类型感性学习的研究非常重要，因为它可以破解内隐记忆形式的机理，可能应用于促进大脑损伤后的恢复。详细了解大脑化学变化的形式可能会帮助创造出新的大脑药理和行为疗法，从而促进大脑中的这些化学变化。
同时还在麻省理工学院大脑和认知科学系任职的比尔说，“大脑研究人员已经对感性学习进行了很长时间的研究，但是直到现在，还没有任何研究触及到感性学习背后的机理”。
研究人员已经确定发现了位于大脑视觉皮层，负责神经键之间的传输，连接神经元和引发刺激选择性反应增强的新型神经传递素受体。由学习引发的大脑变化能增强神经键。
在麻省理工学院进行的此项研究中，年青和成年老鼠大脑中均出现感性学习表明年龄增长不会导致敏锐感觉器官理解能力的丧失。
此项研究小组成员除了比尔还包括皮库尔研究所博士后迈克黑尔·弗伦克尔、俄勒冈卫生科学大学的纳撒尼尔·索特尔、里约联邦大学的安东尼娅·西尼拉·迪沃果、皮库尔研究所博士后邦琼·尤恩和麦克林医院的拉恰尔·勒维。
英文原文：
Researchers uncover basis for perceptual learning
--------------------------------------------------------------------------------
The artist's trained eye can detect distinctions others can't; musicians pick up subtle changes in tone lost on the nonmusical. Brain researchers call these abilities perceptual learning.
Following up on an accidental finding, MIT researchers at the Picower Institute for Learning and Memory and colleagues have uncovered a mechanism for this phenomenon. The study will appear in the Aug. 3 issue of Neuron.
The original idea was to look at how visual deprivation affects the brain. But before mice in the experiment were deprived of vision, researchers recorded baseline measurements by showing them a striped pattern on a video screen.
Unexpectedly, the researchers found that although no change showed up during the viewing session, as few as 12 hours later the mice were more visually "tuned" to the pattern they had seen. Over several sessions, the mice's brain responses to the stripes increased, with the biggest responses occurring to stripes the mice saw more often. The researchers dubbed this change "stimulus selective response potentiation" or SRP.
"The properties of SRP are strikingly similar to those described for some forms of human perceptual learning," said Mark Bear, Picower Professor of Neuroscience and co-author of the study. As a result, "understanding this type of perceptual learning is important because it can reveal mechanisms of implicit memory formation and might be exploited to promote rehabilitation after brain damage. Detailed knowledge of how practice changes brain chemistry is likely to suggest new pharmacological and behavioral therapies to facilitate these changes.
</FORM>-->
We offer a great choice of AI degrees at the postgraduate level
"Brain researchers have studied perceptual learning for a long time, but until now, there has never been any insight into the mechanism behind it," said Bear, who also holds an appointment in MIT's Department of Brain and Cognitive Sciences.
The researchers specifically discovered that new neurotransmitter receptors are delivered to synapses, the connections among neurons, in the brain's visual cortex, leading to SRP. Changes in the brain triggered by learning strengthen the synapses.
In the MIT study, perceptual learning occurred in both young and adult mice, implying that the ability to sharpen sensory perception is not lost with aging.
In addition to Bear, authors include Mikhail Y. Frenkel, Picower Institute postdoctoral associate; Nathaniel B. Sawtell of Oregon Health and Sciences University; Antonia Cinira M. Diogo of the Universidade Federal do Rio de Janeiro; Picower Institute postdoctoral associate Bongjune Yoon; and Rachael L. Neve of McLean Hospital.
