Smith G T
Department of Zoology, University of Washington, Seattle 98195-1800, USA.
Brain Res. 1996 Sep 23;734(1-2):79-85.
Seasonal changes in the brain nuclei that control song behavior in songbirds are among the most striking examples of plasticity in the adult vertebrate brain. Although seasonal changes in the size of these brain nuclei have been found in several species in captivity, results on seasonal changes in the song nuclei of wild songbirds have been equivocal. In the present study, I measured plasma testosterone (T) concentrations and the size of song nuclei across seasons in wild male rufous-sided towhees (Pipilo erythrophthalmus). I found seasonal changes in both T concentrations and the size of song nuclei that were as large as or larger than those observed in this species in captivity. These results demonstrate that seasonal plasticity of the song nuclei occur in wild, as well as captive, songbirds.
在鸣禽中，控制鸣叫行为的脑核的季节性变化是成年脊椎动物大脑可塑性最显著的例子之一。尽管在圈养的几个物种中发现了这些脑核大小的季节性变化，但关于野生鸣禽鸣叫核季节性变化的结果一直存在争议。在本研究中，我测量了野生雄性棕胁唧鹀（Pipilo erythrophthalmus）不同季节的血浆睾酮（T）浓度和鸣叫核的大小。我发现T浓度和鸣叫核大小的季节性变化与该物种在圈养环境中观察到的变化一样大或更大。这些结果表明，鸣叫核的季节性可塑性在野生和圈养鸣禽中均会出现。
