Barron Andrew B, Klein Colin
Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia;
Department of Philosophy and Australian Research Council Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, NSW 2109, Australia.
Proc Natl Acad Sci U S A. 2016 May 3;113(18):4900-8. doi: 10.1073/pnas.1520084113. Epub 2016 Apr 18.
How, why, and when consciousness evolved remain hotly debated topics. Addressing these issues requires considering the distribution of consciousness across the animal phylogenetic tree. Here we propose that at least one invertebrate clade, the insects, has a capacity for the most basic aspect of consciousness: subjective experience. In vertebrates the capacity for subjective experience is supported by integrated structures in the midbrain that create a neural simulation of the state of the mobile animal in space. This integrated and egocentric representation of the world from the animal's perspective is sufficient for subjective experience. Structures in the insect brain perform analogous functions. Therefore, we argue the insect brain also supports a capacity for subjective experience. In both vertebrates and insects this form of behavioral control system evolved as an efficient solution to basic problems of sensory reafference and true navigation. The brain structures that support subjective experience in vertebrates and insects are very different from each other, but in both cases they are basal to each clade. Hence we propose the origins of subjective experience can be traced to the Cambrian.
意识如何、为何以及何时进化仍然是备受热议的话题。解决这些问题需要考虑意识在动物系统发育树中的分布情况。在此我们提出，至少有一个无脊椎动物类群——昆虫，具备意识最基本的方面：主观体验。在脊椎动物中，主观体验的能力由中脑的整合结构所支撑，这些结构会对处于空间中的活动动物的状态进行神经模拟。这种从动物视角对世界的整合且以自我为中心的表征足以产生主观体验。昆虫大脑中的结构执行类似的功能。因此，我们认为昆虫大脑也支持主观体验的能力。在脊椎动物和昆虫中，这种行为控制系统的形式都是作为解决感觉反馈和真正导航等基本问题的有效方案而进化的。支持脊椎动物和昆虫主观体验的大脑结构彼此差异很大，但在这两种情况下，它们都是各自类群的基础结构。因此我们提出，主观体验的起源可以追溯到寒武纪。
