Bergan Joseph F, Ro Peter, Ro Daniel, Knudsen Eric I
Department of Neurobiology, Stanford University School of Medicine, Stanford, California 94305-5125, USA.
J Neurosci. 2005 Oct 19;25(42):9816-20. doi: 10.1523/JNEUROSCI.2533-05.2005.
The optic tectum (OT) of barn owls contains topographic maps of auditory and visual space. Barn owls reared with horizontally displacing prismatic spectacles (prisms) acquire a novel auditory space map in the OT that restores alignment with the prismatically displaced visual map. Although juvenile owls readily acquire alternative maps of auditory space as a result of experience, this plasticity is reduced greatly in adults. We tested whether hunting live prey, a natural and critically important behavior for barn owls, increases auditory map plasticity in adult owls. Two groups of naive adult owls were fit with prisms. The first group was fed dead mice during 10 weeks of prism experience, while the second group was required to hunt live prey for an identical period of time. When the owls hunted live prey, auditory maps shifted substantially farther (five times farther, on average) and the consistency of tuning curve shifts within each map increased. Only a short period of time in each day, during which the two groups experienced different conditions, accounts for this effect. In addition, increased map plasticity correlated with behavioral improvements in the owls' ability to strike and capture prey. These results indicate that the experience of hunting dramatically increases adult adaptive plasticity in this pathway.
仓鸮的视顶盖（OT）包含听觉和视觉空间的地形图。用水平移位的棱镜眼镜（棱镜）饲养的仓鸮在视顶盖中获得了一种新的听觉空间图，该图恢复了与棱镜移位后的视觉图的对齐。尽管幼年仓鸮由于经验很容易获得听觉空间的替代图，但这种可塑性在成年仓鸮中大大降低。我们测试了捕食活猎物（仓鸮的一种自然且至关重要的行为）是否会增加成年仓鸮的听觉图谱可塑性。两组未接触过实验的成年仓鸮佩戴了棱镜。第一组在佩戴棱镜的10周内喂食死老鼠，而第二组在相同时间段内需要捕食活猎物。当仓鸮捕食活猎物时，听觉图谱的移位幅度明显更大（平均大五倍），并且每个图谱内调谐曲线移位的一致性增加。每天只有一小段时间两组经历不同条件，这就是造成这种效果的原因。此外，图谱可塑性的增加与仓鸮打击和捕获猎物能力的行为改善相关。这些结果表明，捕食经历显著增加了这条通路中成年仓鸮的适应性可塑性。
