Pedunculopontine nucleus

Pedunculopontine nucleus
Pedunculopontine nucleus at number 13
Details
Identifiers
Latinnucleus tegmentalis pedunculopontinus
MeSHD045042
NeuroNames504
NeuroLex IDbirnlex_1437
TA98A14.1.06.336
TA25895
FMA72429
Anatomical terms of neuroanatomy

The pedunculopontine nucleus (PPN) or pedunculopontine tegmental nucleus (PPT or PPTg) is a collection of neurons located in the upper pons in the brainstem.[1][2] It is involved in voluntary movements,[3] arousal, and provides sensory feedback to the cerebral cortex and one of the main components of the ascending reticular activating system.[4][5] It is a potential target for deep brain stimulation treatment for Parkinson's disease.[6] It was first described in 1909 by Louis Jacobsohn-Lask, a German neuroanatomist.[7][8]

Structure and projections

The pedunculopontine nucleus lies below the red nucleus, caudal to the substantia nigra and adjacent to the superior cerebellar peduncle. It has two divisions of subnuclei; the pars compacta, containing mainly cholinergic neurons, and the pars dissipata, containing mainly glutamatergic neurons and some non-cholinergic neurons.[2]

Its neurons project axons to a wide range of areas in the brain,[9] particularly parts of the basal ganglia such as the subthalamic nucleus, substantia nigra pars compacta, and globus pallidus internus. It also sends them to targets in the thalamus, cerebellum, basal forebrain, and lower brainstem, and in the cerebral cortex, the supplementary motor area and somatosensory and motor cortices.[4][5][10]

It receives inputs from many areas of the brain.[9] It both projects to and receives input from most parts of the basal ganglia, with the exception of the substantia nigra pars compacta (which it projects to but does not receive input from), and the substantia nigra pars reticulata (which it receives input from but does not project to).[4][5]

Functions

The pedunculopontine nucleus is involved in many functions, including arousal, attention, learning, reward, and voluntary limb movements and locomotion.[3][11] While once thought important to the initiation of movement, recent research suggests a role in providing sensory feedback to the cerebral cortex.[3] It is also implicated in the generation and maintenance of REM sleep.[9]

Recent research has discovered that the pedunculopontine nucleus is involved in the planning of movement, and that different networks of neurons in the pedunculopontine nucleus are switched on during real and imagined movement.[11]

Parkinson's disease

Research is being done on whether deep brain stimulation of the pedunculopontine nucleus might be used to improve the gait and postural difficulties found in Parkinson's disease.[3][6] Clinical trials show improvement of balance and postural reactions when the pedunculopontine nucleus is electrically stimulated.[12][13]

References

  1. ^ Jankovic, Joseph (2015). "Gait disorders". In Jankovic, Joseph (ed.). Movement Disorders, An Issue of Neurologic Clinics. Philadelphia, PA: Elsevier. pp. 249–268. ISBN 978-0-323-35446-2.
  2. ^ a b French, IT; Muthusamy, KA (2018). "A Review of the Pedunculopontine Nucleus in Parkinson's Disease". Frontiers in Aging Neuroscience. 10: 99. doi:10.3389/fnagi.2018.00099. PMC 5933166. PMID 29755338.
  3. ^ a b c d Tsang EW, Hamani C, Moro E, Mazzella F, Poon YY, Lozano AM, Chen R (2010). "Involvement of the human pedunculopontine nucleus region in voluntary movements". Neurology. 75 (11): 950–9. doi:10.1212/WNL.0b013e3181f25b35. PMC 2942031. PMID 20702790.
  4. ^ a b c Garcia-Rill E (1991). "The pedunculopontine nucleus". Prog. Neurobiol. 36 (5): 363–89. doi:10.1016/0301-0082(91)90016-t. PMID 1887068. S2CID 40467457.
  5. ^ a b c Winn P (October 2006). "How best to consider the structure and function of the pedunculopontine tegmental nucleus: evidence from animal studies". J. Neurol. Sci. 248 (1–2): 234–50. doi:10.1016/j.jns.2006.05.036. PMID 16765383. S2CID 23034945.
  6. ^ a b Benarroch, Eduardo E. (19 March 2013). "Pedunculopontine nucleus Functional organization and clinical implications". Neurology. 80 (12): 1148–1155. doi:10.1212/WNL.0b013e3182886a76. PMID 23509047. S2CID 22239596.
  7. ^ Jenkinson N, Nandi D (July 2009). "Anatomy, Physiology, and Pathophysiology of the Pedunculopontine Nucleus". Mov Disord. 24 (3): 319–328. doi:10.1002/mds.22189. PMID 19097193. S2CID 14475183.
  8. ^ Über die Kerne des menschlichen Hirnstamms (Medulla oblongata, Pons und Pedunculus cerebri), Berlin, 1909. pag. 58, fig. 22
  9. ^ a b c Mena-Segovia, Juan; Bolam, J. Paul; Martinez-Gonzalez, Cristina (2011). "Topographical Organization of the Pedunculopontine Nucleus". Frontiers in Neuroanatomy. 5: 22. doi:10.3389/fnana.2011.00022. PMC 3074429. PMID 21503154.
  10. ^ Aravamuthan BR, Muthusamy KA, Stein JF, Aziz TZ, Johansen-Berg H (2007). "Topography of cortical and subcortical connections of the human pedunculopontine and subthalamic nuclei". NeuroImage. 37 (3): 694–705. doi:10.1016/j.neuroimage.2007.05.050. PMID 17644361. S2CID 3348936.
  11. ^ a b Tattersall TL, et al. (2014). "Imagined gait modulates neuronal network dynamics in the human pedunculopontine nucleus" (PDF). Nature Neuroscience. 17 (3): 449–454. doi:10.1038/nn.3642. PMID 24487235. S2CID 405368.
  12. ^ "Characterising, Understanding, and Treating Balance Impairment in Parkinson’s Disease". Brain Foundation Research Report. brainfoundation.org.au/wp-content/uploads/2022/08/Research-Report-Wesley-Thevathsan-Web-1.pdf
  13. ^ Perera, Thushara; Tan, Joy L.; Cole, Michael H.; Yohanandan, Shivy A. C.; Silberstein, Paul; Cook, Raymond; Peppard, Richard; Aziz, Tipu; Coyne, Terry; Brown, Peter; Silburn, Peter A.; Thevathasan, Wesley (2018-10-01). "Balance control systems in Parkinson's disease and the impact of pedunculopontine area stimulation". Brain: A Journal of Neurology. 141 (10): 3009–3022. doi:10.1093/brain/awy216. ISSN 1460-2156. PMC 6158752. PMID 30165427.