Centre of Computational Neuroscience and Robotics, University of Sussex, Brighton BN1 9QG, UK.
J Exp Biol. 2011 Aug 15;214(Pt 16):2739-48. doi: 10.1242/jeb.058537.
The visually guided foraging routes of some formicine ants are individually stereotyped, suggesting the importance of visual learning in maintaining these routes. We ask here whether the wood ant Formica rufa learns a sequence of visual features encountered at different stages along a route, as reported for honeybees. We trained ants in several simple mazes to follow two alternative routes. Along each two-stage route, the ants first encountered one of two priming stimuli. The identity of the priming stimulus determined which of two choice stimuli was rewarded in the second stage of the route. As stimuli we used ultraviolet and yellow/green light panels, and two black-and-white patterns. Did ants learn to pair each colour with the appropriate black-and-white pattern? Ants learnt readily to discriminate between the two coloured stimuli or between the two black-and-white patterns. They could also pair coloured and black-and-white patterns, provided that the two were presented simultaneously. The ants' behaviour with sequential stimuli varied according to whether the priming stimulus was a coloured stimulus or a black-and-white pattern. When the priming stimulus was coloured, ants seemed to learn the two sequences, but tests showed that their success was probably caused by the after-effects of colour adaptation. With a black-and-white priming stimulus and a coloured second stage stimulus, robust sequential learning could not be demonstrated, although under certain experimental conditions a tiny proportion of ants did acquire the sequence. Thus, ants perform conditional discriminations reliably when priming and choice stimuli are simultaneous, but they usually fail when the stimuli are sequential.
一些木蚁的视觉导向觅食路线具有个体刻板性，这表明视觉学习在维持这些路线中的重要性。我们在这里询问木蚁 Formica rufa 是否像蜜蜂一样，学习在路线的不同阶段遇到的一系列视觉特征的序列。我们在几个简单的迷宫中训练蚂蚁，让它们选择两条替代路线。在每条两段式路线中，蚂蚁首先遇到两个启动刺激之一。启动刺激的身份决定了在路线的第二阶段哪个选择刺激会得到奖励。我们使用紫外线和黄/绿光面板以及两个黑白图案作为刺激。蚂蚁是否学会将每种颜色与相应的黑白图案配对？蚂蚁很快学会区分两种颜色刺激或两种黑白图案。只要同时呈现两种颜色和黑白图案，它们也可以将它们配对。蚂蚁对顺序刺激的行为根据启动刺激是颜色刺激还是黑白图案而有所不同。当启动刺激是颜色刺激时，蚂蚁似乎学习了这两个序列，但测试表明它们的成功可能是由颜色适应的后效引起的。当使用黑白启动刺激和彩色第二阶段刺激时，虽然在某些实验条件下，一小部分蚂蚁确实可以获得序列，但不能证明存在稳健的序列学习。因此，当启动和选择刺激同时存在时，蚂蚁可以可靠地执行条件辨别，但当刺激是序列时，它们通常会失败。
