Neural substrates involved in the processing of cognitive information in fish (Pseudotropheus sp)

上个世纪的行为研究表明，鱼类拥有与哺乳动物和鸟类相媲美的认知能力。然而，不幸的是，相对较少的研究已经成功地确定了参与鱼的认知信息处理的神经基质。因此，一些信息在非常有限的主题上是可用的，即经典或工具条件反射，回避学习和空间认知，而对许多其他认知能力重要的大脑区域仍然完全未知。这些能力包括（但当然不限于）社会学习的各个方面（例如个体识别、信息传递或马基雅维利式智力）、辨别学习（其中刺激可以从2D到3D变化，静止到移动的物体等）、分类能力和记忆存储。我认为不仅是端脑，间脑内的特定区域也对鱼类的认知信息处理起着关键作用。生活在复杂栖息地的（群居）物种的大脑，如珊瑚鱼或丽鱼，有几个大脑区域或核（如肾小球核），而在更基本的硬骨鱼中，如骨舌鱼（如非洲弱电鱼）、舌形鱼（如鳗鱼）和团形鱼（如鲱鱼）中没有发现。在现代硬骨鱼的端脑或间脑中发现的这种衍生结构的发展很可能与更复杂的社会等级和复杂的栖息地有关，从而与更复杂的认知能力有关。本提案旨在缩小当前文献中关于详细结构-功能关系的差距，以及对识别涉及鱼类认知信息处理的大脑结构的日益增长的需求，这些结构位于端脑内和端脑外（认知信息处理的主要候选者，也是迄今为止研究最好的）。选择性损伤实验结合自发性行为观察（实验1a和b）和专门设计的训练实验（实验2），揭示了特定脑区在个体识别、视觉辨别、时间-地点学习和空间定向等方面的重要性。IEG研究（实验3）将进一步阐明参与视觉辨别学习过程的特定大脑区域，特别是个体识别（社会认知）。本研究的六个目标核或区域包括三个来自端脑的区域；它们是(1)白质背区，(2)白质外侧区和(3)白质内侧区。此外，间脑中的三个区域是目标，迄今为止从未在认知环境中进行过研究。这些是(4)肾小球核，(5)下叶和(6)丘脑背/腹侧。

Behavioral studies over the last century have shown that fish possess cognitive abilities rivaling those of mammals and birds. Unfortunately though, comparably few studies have successfully identified the neural substrates involved in the processing of cognitive information in fish. Consequentially, some information is available on a very limited number of topics, i.e. classical or instrumental conditioning, avoidance learning and spatial cognition while the brain areas important for many other cognitive abilities remain completely unknown. Such abilities include (but are certainly not limited to) all aspects of social learning (e.g. individual recognition, information transfer or Machiavellian intelligence), discrimination learning (whereby stimuli can vary from 2D to 3D, stationary to moving objects, etc.), categorization abilities and memory storage. I propose that not only the telencephalon but also specific regions within the diencephalon hold key functions for the processing of cognitive information in fish. Brains of (social) species living in complex habitats, such as coral reef fish or cichlids feature several brain areas or nuclei (e.g. the nucleus glomerulosus) not found in more basal teleost fish such as the osteoglossomorpha (e.g. African weakly electric fish), elopomorpha (e.g. eels) and clupeomorpha (e.g. herrings). The development of such derived structures found in the telencephalon or diencephalon of modern teleosts may quite likely be linked to more complex social hierarchies and complex habitats and thereby to more elaborate cognitive abilities. This proposal aims to narrow the gap in the current literature regarding detailed structure-function relationships and the growing need for the identification of brain structures involved in the processing of cognitive information in fishes, located both within and outside of the telencephalon (a prime candidate for cognitive information processing and also the best studied so far). Selective lesion experiments used in combination with behavioral observations of spontaneous behavior (experiment 1A&B) as well as specifically designed training assays (experiment 2) are proposed to reveal the significance of specific brain regions for aspects of individual recognition, visual discrimination, time-place learning and spatial orientation. IEG studies (experiment 3) will shed further light onto specific brain regions involved in the process of visual discrimination learning and specifically recognition of individuals (social cognition). The six target nuclei or areas in this study include three areas from the telencephalon; these are (1) the dorsal zone of the pallium, (2) the lateral zone of the pallium and (3) the medial zone of the pallium. Additionally, three areas are targeted in the diencephalon, which so far have never been investigated in a cognitive context. These are (4) the nucleus glomerulosus, (5) the inferior lobes and (6) the dorsal/ventral thalamus.