De Groof Geert, Verhoye Marleen, Poirier Colline, Leemans Alexander, Eens Marcel, Darras Veerle M, Van der Linden Annemie
Bio-Imaging Laboratory, University of Antwerp, Antwerp, Belgium.
J Neurosci. 2009 Oct 28;29(43):13557-65. doi: 10.1523/JNEUROSCI.1788-09.2009.
The song control system (SCS) of seasonal songbirds shows remarkable seasonal plasticity. Male starlings (Sturnus vulgaris) sing throughout the year, but in the breeding season, when concentrations of testosterone are elevated, the song is highly sexually motivated. The main goal of this study was to investigate structural seasonal changes in regions involved in auditory processing and in socio-sexual behavior. Using in vivo Diffusion Tensor Imaging (DTI), we measured in breeding and nonbreeding seasons volume and tissue characteristics of several brain regions of nine adult male starlings. We demonstrate that the songbird brain exhibits an extreme seasonal plasticity not merely limited to the SCS. Volumetric analysis showed seasonal telencephalon volume changes and more importantly also a volumetric change in the caudal region of the nidopallium (NCM), a region analogous to the mammalian secondary auditory cortex. Analysis of the DTI data allowed detection of seasonal changes in cellular attributes in NCM and regions involved in social behavior. This study extends our view on a seasonally dynamic avian brain which not only hones its song control system but also auditory and social systems to be prepared for the breeding season.
季节性鸣禽的歌声控制系统（SCS）具有显著的季节性可塑性。雄性椋鸟（Sturnus vulgaris）全年都会鸣叫，但在繁殖季节，当睾酮浓度升高时，歌声具有强烈的性动机。本研究的主要目的是调查参与听觉处理和社会性行为的区域的结构季节性变化。我们使用活体扩散张量成像（DTI），在繁殖季节和非繁殖季节测量了9只成年雄性椋鸟几个脑区的体积和组织特征。我们证明，鸣禽大脑表现出极端的季节性可塑性，不仅仅局限于歌声控制系统。体积分析显示端脑体积有季节性变化，更重要的是，巢皮质尾侧区域（NCM）也有体积变化，该区域类似于哺乳动物的次级听觉皮层。对DTI数据的分析能够检测到NCM和参与社会行为区域的细胞属性的季节性变化。这项研究扩展了我们对季节性动态鸟类大脑的认识，其不仅优化了歌声控制系统，还优化了听觉和社会系统，为繁殖季节做好准备。
