Sound Categories Are Represented as Distributed Patterns in the Human Auditory Cortex
Sound Categories Are Represented as Distributed Patterns in the Human Auditory Cortex
复制标题
DOI：
10.1016/j.cub.2009.01.066
复制
发表时间：
2009-03-24
期刊：
影响因子：
9.2
通讯作者：
Formisano, Elia
中科院分区：
文献类型：
--
作者：
Staeren, Noel;Renvall, Hanna;Formisano, Elia
识别声音的能力使人类和动物即使在没有视觉信息的情况下也能有效地检测到与行为相关的事件。人类大脑中的声音识别被认为是通过几个功能专门的区域进行的，最终在皮层模块中进行特定类别的处理[1-5]。在当前的高分辨率fMRI实验中，我们通过使用控制良好的自然听觉刺激和采用基于迭代机器学习算法[6]的高级分析策略来挑战该模型，该算法允许对空间分布和局部响应模式进行建模。猫、女歌手、原声吉他和音调的声音随时间变化的频谱特征被控制，并以三种不同的音调水平呈现给受试者。声音类别信息不能用传统的基于对比的方法分析检测到，但可以用多体素模式分析检测到，并归因于颞上皮层的空间分布区域。在初级听觉区域的侧侧，我们观察到一种更局部化的音调处理模式。我们的研究结果表明，人类听觉皮层内分布的神经元群，包括通常与低水平听觉处理相关的区域，需要超越其物理特性的声音分类表征。
The ability to recognize sounds allows humans and animals to efficiently detect behaviorally relevant events, even in the absence of visual information. Sound recognition in the human brain has been assumed to proceed through several functionally specialized areas, culminating in cortical modules where category-specific processing is carried out [1-5]. In the present high-resolution fMRI experiment, we challenged this model by using well-controlled natural auditory stimuli and by employing an advanced analysis strategy based on an iterative machine-learning algorithm [6] that allows modeling of spatially distributed, as well as localized, response patterns. Sounds of cats, female singers, acoustic guitars, and tones were controlled for their time-varying spectral characteristics and presented to subjects at three different pitch levels. Sound category information-not detectable with conventional contrast-based methods analysis-could be detected with multivoxel pattern analyses and attributed to spatially distributed areas over the supratemporal cortices. A more localized pattern was observed for processing of pitch laterally to primary auditory areas. Our findings indicate that distributed neuronal populations within the human auditory cortices, including areas conventionally associated with lower-level auditory processing, entail categorical representations of sounds beyond their physical properties.