Topological relation of chick thalamofugal visual projections with hyper pallium revealed by three color tracers.
In birds, there are two visual projections from retina to higher pallium, i.e., tectofugal and thalamofugal pathways. The latter one is lateralized in chick and suggested to be involved in visually evoked social behavior, like recognition of novelty, predator, and conspecific animals. We wanted to establish functionally relevant topological connection map between thalamic nuclei and hyperpallium apicale (HA) and carried out tracing study with three color fluorescent tracers. The tracers were serially injected in HA either along with the medial-lateral (M-L) or anterior-posterior (A-P) axis. We found that M-L axis and A-P axis in HA were transferred into the dorsal-ventral axis and the medial-lateral axis, respectively within the nucleus geniculatus lateralis pars dorsalis (GLd). In another word, the medial part of nucleus dorsolateralis anterior thalami pars lateralis (DLLv) projected to anterior part of HA and the ventral part of nucleus dorsolateralis anterior thalami pars lateralis pas ventralis (DLLd) projects to lateral HA. This result suggests that thalamus would process information in parallel through each subnuclei and elaborate coordination among them in relation to topological map presented in higher pallium.
Koshiba
Mamiko
M
Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo 184-8588, Japan.
Yohda
Masafumi
M
Nakamura
Shun
S
D000818:Animals; D000831:Animals, Newborn; D001931:Brain Mapping; D002645:Chickens; D003952:Diagnostic Imaging / Q000379:methods; D005456:Fluorescent Dyes; D007839:Functional Laterality / Q000502:physiology; D008297:Male; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence / Q000379:methods; D016571:Neural Networks, Computer; D013477:Superior Colliculi / Q000033:anatomy & histology* / Q000378:metabolism; D013787:Thalamic Nuclei / Q000033:anatomy & histology* / Q000378:metabolism; D014795:Visual Pathways / Q000033:anatomy & histology* / Q000378:metabolism
D005456:Fluorescent Dyes