Gerber Bertram, Hendel Thomas
Universität Würzburg, Lehrstuhl für Genetik und Neurobiologie, Biozentrum Am Hubland, 970 74 Würzburg, Germany.
Proc Biol Sci. 2006 Dec 7;273(1604):2965-8. doi: 10.1098/rspb.2006.3673.
Why does Pavlov's dog salivate? In response to the tone, or in expectation of food? While in vertebrates behaviour can be driven by expected outcomes, it is unknown whether this is true for non-vertebrates as well. We find that, in the Drosophila larva, odour memories are expressed behaviourally only if animals can expect a positive outcome from doing so. The expected outcome of tracking down an odour is determined by comparing the value of the current situation with the value of the memory for that odour. Memory is expressed behaviourally only if the expected outcome is positive. This uncovers a hitherto unrecognized evaluative processing step between an activated memory trace and behaviour control, and argues that learned behaviour reflects the pursuit of its expected outcome. Shown in a system with a simple brain, an apparently cognitive process like representing the expected outcome of behaviour seems to be a basic feature of behaviour control.
为什么巴甫洛夫的狗会流口水？是对铃声做出反应，还是期待食物？虽然在脊椎动物中，行为可以由预期结果驱动，但对于无脊椎动物是否也是如此却尚不清楚。我们发现，在果蝇幼虫中，只有当动物能够预期这样做会带来积极结果时，气味记忆才会通过行为表现出来。追踪一种气味的预期结果是通过将当前情况的价值与该气味记忆的价值进行比较来确定的。只有当预期结果为正时，记忆才会通过行为表现出来。这揭示了在激活的记忆痕迹与行为控制之间一个迄今未被认识的评估处理步骤，并表明习得行为反映了对其预期结果的追求。在一个具有简单大脑的系统中显示，像表征行为预期结果这样一个明显的认知过程似乎是行为控制的一个基本特征。
