Huo Juan, Murray Alan
Doctoral Training Center, School of Informatics, The University of Edinburgh, Mayfield Road, Edinburgh, UK.
Neural Netw. 2009 Sep;22(7):913-21. doi: 10.1016/j.neunet.2008.10.007. Epub 2008 Nov 13.
To localize a seen object, the superior colliculus of the barn owl integrates the visual and auditory localization cues which are accessed from the sensory system of the brain. These cues are formed as visual and auditory maps. The alignment between visual and auditory maps is very important for accurate localization in prey behavior. Blindness or prism wearing may interfere this alignment. The juvenile barn owl could adapt its auditory map to this mismatch after several weeks training. Here we investigate this process by building a computational model of auditory and visual integration in deep Superior Colliculus (SC). The adaptation of the map alignment is based on activity dependent axon developing in Inferior Colliculus (IC). This axon growing process is instructed by an inhibitory network in SC while the strength of the inhibition is adjusted by Spike Timing Dependent Plasticity (STDP). The simulation results of this model are in line with the biological experiment and support the idea that STDP is involved in the alignment of sensory maps. This model also provides a new spiking neuron based mechanism capable of eliminating the disparity in visual and auditory map integration.
为了定位所见物体，仓鸮的上丘整合了从大脑感觉系统获取的视觉和听觉定位线索。这些线索以视觉和听觉图谱的形式形成。视觉和听觉图谱之间的对齐对于捕食行为中的准确定位非常重要。失明或佩戴棱镜可能会干扰这种对齐。幼年仓鸮在经过几周训练后可以使其听觉图谱适应这种不匹配。在这里，我们通过构建一个关于深上丘（SC）中听觉和视觉整合的计算模型来研究这个过程。图谱对齐的适应基于下丘（IC）中依赖活动的轴突发育。这个轴突生长过程由上丘中的一个抑制性网络指导，而抑制的强度由尖峰时间依赖可塑性（STDP）调整。该模型的模拟结果与生物学实验一致，并支持STDP参与感觉图谱对齐的观点。这个模型还提供了一种基于脉冲神经元的新机制，能够消除视觉和听觉图谱整合中的差异。
