Pulvinar nuclei


The pulvinar nuclei or nuclei of the pulvinar are the nuclei located in the thalamus. As a group they make up the collection called the pulvinar of the thalamus, usually just called the pulvinar.
The pulvinar is usually grouped as one of the lateral thalamic nuclei in rodents and carnivores, and stands as an independent complex in primates.

Structure

By convention, the pulvinar is divided into four nuclei:
TA alphanumeric identifierTA nameEnglish translation
A14.1.08.611nucleus pulvinaris anterioranterior pulvinar nucleus
A14.1.08.612nucleus pulvinaris inferiorinferior pulvinar nucleus
A14.1.08.613nucleus pulvinaris lateralislateral pulvinar nucleus
A14.1.08.614nucleus pulvinaris medialismedial pulvinar nucleus

Their connectomic details are as follows:
Lesions of the pulvinar can result in neglect syndromes and attentional deficits. In addition, lesions in early life can impact normal visuomotor behaviors such as reaching and grasping. Furthermore, the pulvinar was demonstrated to be instrumental in the preservation of vision afforded to a boy who lost his primary visual cortex bilaterally at birth. Strokes affecting the pulvinar have also been implicated in the development of chronic pain.

Other animals

The pulvinar varies in importance in different animals: it is virtually nonexistent in the rat, and grouped as the lateral posterior-pulvinar complex with the lateral posterior thalamic nucleus due to its small size in cats. In humans it makes up roughly 40% of the thalamus making it the largest of its nuclei. Significant research has been undertaken in the marmoset examining the role of the retinorecipient region of the inferior pulvinar, which projects to visual cortical area MT, in the early development of MT and the dorsal stream, as well as following early-life lesions of the primary visual cortex.

Etymology and pronunciation

The word pulvinar comes to scientific English vocabulary via New Latin from classical Latin pulvinus, "cushion". In the religion of ancient Rome, a pulvinar was an empty throne, a cushioned couch for occupation by a deity. Like the cervix uteri is usually just called the cervix, the pulvinar thalami is usually just called the pulvinar; no other anatomic structure in today's Terminologia Anatomica is called a pulvinar, although in older terminology a part of the glomus body was called the pulvinar tunicae internae segmenti arterialis anastomosis arteriovenae glomeriformis. Each pulvinar nucleus has its own set of cortical connections.

Additional images