Brauth S E, McHale C M, Brasher C A, Dooling R J
Department of Psychology, University of Maryland, College Park.
Brain Behav Evol. 1987;30(3-4):174-99. doi: 10.1159/000118645.
Thalamo-telencephalic auditory pathways in the budgerigar (Melopsittacus undulatus) were studied using horseradish peroxidase (HRP) histochemistry and amino acids autoradiography. The results indicate that in this species the thalamic auditory relay nucleus, n. ovoidalis, projects upon a circumscribed region of the caudal and caudomedial neostriatum including field 'L' and immediately adjacent portions of the neostriatum intermedium, pars dorsolateralis (NIDL). This region of NIDL also receives inputs from another thalamic nucleus, n. dorsolateralis posterior (DLP). In the DLP is in receipt of tectal inputs. Projections of DLP upon NIDL were confirmed with amino acids autoradiography. The results of the HRP experiments indicate that different portions of n. ovoidalis project upon different portions of field 'L' and NIDL. Neurons in the dorsal and lateral portions of the n. ovoidalis project upon more medial portions of field 'L'. Neurons located centrally in the n. ovoidalis project upon central and lateral portions of field 'L'. Neurons in the ventromedial portion of the n. ovoidalis are labeled in all cases in which HRP is placed in either field 'L' or in the DLP projection field immediately adjacent to field 'L' proper. HRP injections placed in NIDL lateral to the projection fields of the n. ovoidalis and DLP label neurons within other diencephalic nuclei including the n. subrotundus. The caudal and intermediate levels of the neostriatum intermedium apparently serve as a complex processing area for many thalamic inputs in this species. The existence of multiple ascending thalamo-telencephalic projections from portions of the thalamus receiving inputs from both the visual (i.e., tectal) and auditory (i.e., n. mesencephalicus lateralis pars dorsalis) portions of the midbrain roof (i.e., from DLP and from n. ovoidalis) suggests the possibility that intermodal associations may take place in these telencephalic fields. Such partially converging pathways may provide a basics for intermodal associations which are important in individual recognition and social signalling systems in this species.
利用辣根过氧化物酶（HRP）组织化学和氨基酸放射自显影技术，对虎皮鹦鹉（Melopsittacus undulatus）的丘脑 - 端脑听觉通路进行了研究。结果表明，在该物种中，丘脑听觉中继核——卵圆核，投射到尾侧和尾内侧新纹状体的一个限定区域，包括“L”区以及新纹状体中间部背外侧部（NIDL）紧邻“L”区的部分。NIDL的这个区域还接受来自另一个丘脑核——背外侧后核（DLP）的输入。DLP接受顶盖的输入。通过氨基酸放射自显影证实了DLP向NIDL的投射。HRP实验结果表明，卵圆核的不同部分投射到“L”区和NIDL的不同部分。卵圆核背侧和外侧部分的神经元投射到“L”区更内侧的部分。位于卵圆核中央的神经元投射到“L”区的中央和外侧部分。在所有将HRP置于“L”区或紧邻“L”区的DLP投射区的情况下，卵圆核腹内侧部分的神经元都被标记。将HRP注射到卵圆核和DLP投射区外侧的NIDL，会标记包括亚圆形核在内的其他间脑核内的神经元。新纹状体中间部的尾侧和中间水平显然是该物种许多丘脑输入的复杂处理区域。来自丘脑部分的多个上行丘脑 - 端脑投射的存在，这些丘脑部分从中脑顶盖的视觉（即顶盖）和听觉（即中脑外侧核背侧部）部分接收输入（即来自DLP和卵圆核），这表明在这些端脑区域可能发生模式间关联。这种部分汇聚的通路可能为模式间关联提供基础，而模式间关联在该物种的个体识别和社会信号系统中很重要。
