Thalamic reticular nucleus explained
| Thalamic reticular nucleus |
| Latin: | nucleus reticularis thalami |
| Ispartof: | Thalamus |
The thalamic reticular nucleus is part of the ventral thalamus that forms a capsule around the thalamus laterally. However, recent evidence from mice and fish question this statement and define it as a dorsal thalamic structure. It is separated from the thalamus by the external medullary lamina. Reticular nucleus cells are all GABAergic, and have discoid dendritic arbors in the plane of the nucleus.
Thalamic Reticular Nucleus is variously abbreviated TRN, RTN, NRT, and RT. The TRN is found in all mammals.
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.
The outputs from the primary thalamic reticular nucleus 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. Instead it modulates the information from other nuclei in the thalamus. Its function is modulatory on signals going through the thalamus (and the reticular nucleus).
The thalamic reticular nucleus receives massive projections from the external segment of the globus pallidus, thought to play a part in disinhibition of thalamic cells, which is essential for initiation of movement (Parent and Hazrati, 1995).
It has been suggested that the reticular nucleus receives afferent input from the reticular formation and in turn projects to the other thalamic nuclei, regulating the flow of information through these to the cortex. 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.
References
- Book: Brodal . Per . The Central Nervous System . Oxford University Press . New York . 2016 . 5th . 978-0-19-022895-8.
- Crabtree . John W. . Isaac . John T.R. . New intrathalamic pathways allowing modality-related and cross-modality switching in the dorsal thalamus . The Journal of Neuroscience . 22 . 19 . 8754–8761 . October 2002 . 12351751 . 6757787 . 10.1523/JNEUROSCI.22-19-08754.2002.
- Jones . Edward G. . Edward G. Jones . Some aspects of the organization of the thalamic reticular complex . J. Comp. Neurol. . 162 . 3 . 285–308 . 1975 . 1150923 . 10.1002/cne.901620302. 28724898 .
- Book: The Thalamus . Springer . en . 10.1007/978-1-4615-1749-8 . 1985 . 978-1-4613-5704-9 . 41337319 . Jones . Edward G . Edward G. Jones . 710.
- Parent . André . Hazrati . Lili-Naz . 1995 . Functional anatomy of the basal ganglia. II. The place of subthalamic nucleus and external pallidium in basal ganglia circuitry . Brain Research Reviews . 20 . 1 . 128–154 . 10.1016/0165-0173(94)00008-D.
- Book: The cerebral cortex and thalamus . 2024 . Oxford University Press . New York . 978-0-19-767615-8 . Usrey . W. Martin . Sherman . S. Murray . The thalamic reticular nucleus: Anatomo-functional mechanisms and concept . Pinault . Didier . 163–175.
- Scholpp . Steffen . Delogu . Alessio . Gilthorpe . Jonathan . Peukert . Daniela . Schindler . Simone . Lumsden . Andrew . Her6 regulates the neurogenetic gradient and neuronal identity in the thalamus . Proceedings of the National Academy of Sciences of the USA . 106 . 47 . 19895–19900 . November 2009 . 19903880 . 2775703 . 10.1073/pnas.0910894106 . 2009PNAS..10619895S . free.
- Book: The cerebral cortex and thalamus . 2024 . Oxford University Press . New York . 978-0-19-767615-8 . Usrey . W. Martin . Sherman . S. Murray . Introduction and overview . Usrey . W. Martin . Sherman . S. Murray . 3–9.
- Vue TY, Bluske K, Alishahi A, etal . Sonic hedgehog signaling controls thalamic progenitor identity and nuclei specification in mice . J. Neurosci. . 29 . 14 . 4484–97 . April 2009 . 19357274 . 2718849 . 10.1523/JNEUROSCI.0656-09.2009 .
Further reading
- Hestrin. Shaul. 2011. The strength of electrical synapses. Science. 334. 6054. 315–316. 10.1126/science.1213894. 22021844. 4458844. 2011Sci...334..315H.
- Haas . Julie S.. Zavala . Baltazar . Landisman . Carole E. . 2011. Activity-dependent long-term depression of electrical synapses. Science. 334. 6054. 389–393. 10.1126/science.1207502. 22021860. 2011Sci...334..389H. 35398480. 10921920.
