Zhang Weiwei, Luck Steven J
Department of Psychology, University of Iowa, Iowa City, Iowa 52242, USA.
Nature. 2008 May 8;453(7192):233-5. doi: 10.1038/nature06860. Epub 2008 Apr 2.
Limits on the storage capacity of working memory significantly affect cognitive abilities in a wide range of domains, but the nature of these capacity limits has been elusive. Some researchers have proposed that working memory stores a limited set of discrete, fixed-resolution representations, whereas others have proposed that working memory consists of a pool of resources that can be allocated flexibly to provide either a small number of high-resolution representations or a large number of low-resolution representations. Here we resolve this controversy by providing independent measures of capacity and resolution. We show that, when presented with more than a few simple objects, human observers store a high-resolution representation of a subset of the objects and retain no information about the others. Memory resolution varied over a narrow range that cannot be explained in terms of a general resource pool but can be well explained by a small set of discrete, fixed-resolution representations.
工作记忆存储容量的限制在广泛领域中显著影响认知能力，但这些容量限制的本质一直难以捉摸。一些研究人员提出，工作记忆存储一组有限的离散、固定分辨率表征，而另一些人则提出，工作记忆由一组资源组成，这些资源可以灵活分配，以提供少量高分辨率表征或大量低分辨率表征。在这里，我们通过提供容量和分辨率的独立测量来解决这一争议。我们表明，当呈现多个简单物体时，人类观察者会存储其中一部分物体的高分辨率表征，而对其他物体则不保留任何信息。记忆分辨率在一个狭窄范围内变化，这无法用一般的资源池来解释，但可以用一小组离散、固定分辨率表征来很好地解释。
