colliculus superior


su·pe·ri·or col·lic·u·lus

[TA] the paired, larger, rounded anterior eminence of the laminae of mesencephalic tectum; major afferent connections of the superficial layers are the retina and striate cortex; input to deep layers of the colliculus are polymodal. Its efferent connections are with the lower brainstem and spinal cord (tectobulbar tract and tectospinal tract) and with the pulvinar and other cell groups in the caudal part of the thalamus; it participates in the extrageniculate visual pathway. The layers of the superior colliculus from superficial to deep are: zonal layer (stratum zonale), superficial gray layer (stratum griseum superficial), optic layer (stratum opticum), intermediate gray layer (stratum griseum intermedium), intermediate white layer (stratum medullare intermedium), deep gray layer (stratum griseum profundum), and deep white layer (stratum medullare profundum). Synonym(s): colliculus superior [TA], anterior quadrigeminal body, corpus quadrigeminum anterius

colliculus superior

One of two elevations forming the upper portion of the corpora quadrigemina of the midbrain.See also: colliculus