The reciprocal connections of the suprageniculate nucleus and the superior colliculus in the rat.
Reciprocally bilateral connections between the superior colliculus and the suprageniculate nucleus have been studied in the rat, using the anterograde and retrograde transport techniques of HRP. In those cases where the HRP deposit was restricted to the superficial layers of the colliculus, anterogradely labeled fibers and retrogradely labeled neurons were observed in the ipsilateral suprageniculate nucleus. However, upon HRP injection extended into the intermediate layers of the colliculus, the number of labeled fibers and neurons was not only increased ipsilaterally but were also observed in the contralateral suprageniculate nucleus. The density of the labeled fibers and the number of labeled neurons was always greater in the ipsilateral side. These results show that the suprageniculate nucleus and the superior colliculus are connected reciprocally and bilaterally, with an ipsilateral dominance.
D000818:Animals; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013477:Superior Colliculi / Q000033:anatomy & histology*; D013787:Thalamic Nuclei / Q000033:anatomy & histology*; D014795:Visual Pathways / Q000033:anatomy & histology