Lateral geniculate body

The lateral geniculate body is an example of a sensory relay nucleus projecting from the pulvinar of the thalamus. It plays an important role in normal visual processing.

Thalamus, as we all know, is the major sensory relay station situated in the center of the brain. Most of the thalamus comprises of relay nuclei, which receive inputs from dedicated pathways and subsequently project them to the cortex. In this context, the lateral geniculate body (or lateral geniculate nucleus) forms part of the visual pathway and relays sensory visual information from the retina. More specifically, axons of the retinal ganglionic cells in the optic tracts form synapses with the neuronal cell bodies inside the lateral geniculate body (LGB). Next, the LGB conveys this visual information to the primary visual cortex via the thalamocortical projections (a.k.a. optic radiations). These neuronal projections traverse through the parietal lobe as superior optic radiations and through the temporal lobe as inferior optic radiations, prior to reaching the primary visual cortex in the occipital lobe.

A stroke in the lateral geniculate body could lead to a contralateral homonymous hemianopia, while a stroke in the parietal or temporal lobe could lead to contralateral homonymous quadrantanopia, due to separate involvement of superior or inferior optic radiations.