Thalamic reticular nucleus

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.[1][2] It is separated from the thalamus by the external medullary lamina. Reticular nucleus cells are all GABAergic,[3][4][5][6] and have discoid dendritic arbors in the plane of the nucleus.[citation needed]

Thalamic reticular nucleus
Left thalamus reticular nucleus
Thalamus dorsal view
Details
Part ofThalamus
Identifiers
Latinnucleus reticularis thalami
NeuroNames365
NeuroLex IDbirnlex_1721
TA98A14.1.08.638
TA25704
FMA62026
Anatomical terms of neuroanatomy

Thalamic Reticular Nucleus is variously abbreviated TRN, RTN, NRT, and RT. The TRN is found in all mammals.[5]

Input and output

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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.[7][8] 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).[9]

It has been suggested that the reticular nucleus receives afferent input from the reticular formation[citation needed] 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.[10]

For discussion of mapping and cross modality pathways see Crabtree 2002.[11]

Notes

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  1. ^ Vue, Bluske & Alishahi 2009.
  2. ^ Scholpp et al. 2009.
  3. ^ Usrey & Sherman 2024, p. 3.
  4. ^ Jones 1985, p. 710.
  5. ^ a b Pinault 2024, p. 163.
  6. ^ Brodal 2016, p. 572.
  7. ^ Jones 1985, p. 218.
  8. ^ Jones 1975, p. 304.
  9. ^ Parent & Hazrati 1995.
  10. ^ Jones 1975.
  11. ^ Crabtree & Isaac 2002.

References

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  • Brodal, Per (2016). The Central Nervous System (5th ed.). New York: Oxford University Press. ISBN 978-0-19-022895-8.
  • Crabtree, John W.; Isaac, John T.R. (October 2002). "New intrathalamic pathways allowing modality-related and cross-modality switching in the dorsal thalamus". The Journal of Neuroscience. 22 (19): 8754–8761. doi:10.1523/JNEUROSCI.22-19-08754.2002. PMC 6757787. PMID 12351751.
  • Jones, Edward G. (1975). "Some aspects of the organization of the thalamic reticular complex". J. Comp. Neurol. 162 (3): 285–308. doi:10.1002/cne.901620302. PMID 1150923. S2CID 28724898.
  • Jones, Edward G (1985). The Thalamus. Springer. p. 710. doi:10.1007/978-1-4615-1749-8. ISBN 978-1-4613-5704-9. S2CID 41337319.
  • 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. doi:10.1016/0165-0173(94)00008-D.
  • Pinault, Didier (2024). "The thalamic reticular nucleus: Anatomo-functional mechanisms and concept". In Usrey, W. Martin; Sherman, S. Murray (eds.). The cerebral cortex and thalamus. New York: Oxford University Press. pp. 163–175. ISBN 978-0-19-767615-8.
  • Usrey, W. Martin; Sherman, S. Murray (2024). "Introduction and overview". In Usrey, W. Martin; Sherman, S. Murray (eds.). The cerebral cortex and thalamus. New York: Oxford University Press. pp. 3–9. ISBN 978-0-19-767615-8.

Further reading

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