Nottebohm F, Stokes T M, Leonard C M
J Comp Neurol. 1976 Feb 15;165(4):457-86. doi: 10.1002/cne.901650405.
We have traced central nervous pathways controlling bird song in the canary using a combination of behavioral and anatomical techniques. Unilateral electrolytic brain lesions were made in adult male canaries whose song had been previously recorded and analysed on a sound spectrograph. After several days of postoperative recording, the birds were sacrificed and their brains processed histologically for degeneration staining with the Fink-Heimer technique. Although large lesions in the neostriatum and rostral hyperstriatum had no effect on song, severe song deficits followed damage to a discrete large-celled area in the caudal hyperstriatum ventrale (HVc). Degenerating fibers were traced from this region to two other discrete nuclei in the forebrain: one in the parolfactory lobe (area X, a teardrop-shaped small-celled nucleus); and a round large-celled nucleus in the archistriatum (RA). Unilateral lesion of X had no effect on song; lesions of RA, however, caused severe song deficits. Degenerating fibers from RA joined the occipitomesencephalic tract and had widespread ipsilateral projections to the thalamus, nucleus intercollicularis of the midbrain, reticular formation, and medulla. It is of particular interest that direct connections were found onto the cells of the motor nucleus innervating the syrinx, the organ of song production. Unilateral lesions of n. intercollicularis (previously implicated in the control of vocal behavior) had little effect on song. One bilateral lesion of HVc resulted in permanent (9 months) and complete elimination of the audible components of song, although the bird assumed the posture and movements typical of song. Preliminary data suggest that lesions of the left hemisphere result in greater deficits than lesions of the right one. This finding is consistent with earlier reports that the left syrinx controls the majority of song components. Results reported here suggest a localization of vocal control in the canary brain with an overlying left hemispheric dominance.
我们运用行为学和解剖学技术相结合的方法，追踪了金丝雀体内控制鸟鸣的中枢神经通路。对成年雄性金丝雀进行单侧电解脑损伤，这些金丝雀的歌声此前已被录制并在声谱仪上进行分析。术后记录数天后，处死这些鸟，并对其大脑进行组织学处理，采用芬克 - 海默技术进行变性染色。尽管新纹状体和嘴侧上纹状体的大面积损伤对鸟鸣没有影响，但尾侧腹侧上纹状体（HVc）中一个离散的大细胞区域受损后，鸟鸣出现严重缺陷。从该区域追踪到退化纤维至前脑的另外两个离散核团：一个位于副嗅叶（X区，一个泪滴状的小细胞核）；另一个是古纹状体中的圆形大细胞核（RA）。单侧损伤X区对鸟鸣没有影响；然而，损伤RA会导致严重的鸟鸣缺陷。来自RA的退化纤维加入枕中脑束，并广泛地同侧投射至丘脑、中脑的顶盖间核、网状结构和延髓。特别有趣的是，发现有直接连接至支配鸣管（发声器官）的运动核的细胞。单侧损伤顶盖间核（此前认为与发声行为控制有关）对鸟鸣影响很小。单侧HVc损伤导致鸟鸣的可听成分永久性（9个月）且完全消失，尽管鸟仍呈现出典型的鸣唱姿势和动作。初步数据表明，左半球损伤比右半球损伤导致的缺陷更大。这一发现与早期报告一致，即左侧鸣管控制大多数的鸟鸣成分。此处报告的结果表明，金丝雀大脑中存在发声控制的定位，且左半球具有优势地位。
