Thalamic reticular nucleus

The thalamic reticular nucleus is part of the ventral thalamus that forms a capsule around the thalamus laterally. It is separated from the thalamus by the external medullary lamina. Reticular cells are GABAergic, and have discoid dendritic arbors in the plane of the nucleus.

Thalamic Reticular Nucleus is variously abbreviated TRN, RTN, NRT, and RT.

Input and output
The thalamic reticular nucleus receives input from the cerebral cortex and dorsal thalamic nuclei. Most input comes from collaterals of fibers passing through the thalamic reticular nucleus. Primary thalamic reticular nucleus efferent fibers project to dorsal thalamic nuclei, but never to the cerebral cortex. This is the only thalamic nucleus that does not project to the cerebral cortex.The function of the thalamic reticular nucleus is not understood, although it has some role in absence seizures, von Krosigk et al., 1993. There is debate over the presence of distinct sectors within the nucleus that each correspond to a different sensory or cognitive modality.

For original connectivity anatomy see Jones 1975; For discussion of mapping and cross modality pathways see Crabtree 2002.