Centromedian Thalamic Nucleus (CM) / Parafasicular (Pf) complex
Disorders Treated with Stimulation
- Primary indications: Epilepsy
- Investigational applications: May be effective in treating Tourette syndrome and chronic pain [1]
Location
- The CM nucleus is loacted in the posterior thalamus, near the midline, anterior to the pulvinar. [2] The CM-PF complex is located posterolateral to the fasciculus retroflexus (the fiber bundle that that gives the PF its name) [3]
- The Pf nucleus is directly medial to the CM and closely interrelated, so is shown in this graphic. The CM nucleus is typically targeted for DBS however.
Associated Tracts
- The CM is a waystation in the thalamus with numerous connections, the majority of which are not depicted on these images.
- Thalamocortical Projections: There are broad projections of white matter tracts from the CM in the thalamus to cortical locations including the precentral gyrus, superior frontal gyrus, and bilateral cerebellar hemispheres. Stimulating these projections at their termini in the CM appears to result in more efficacious neuromodulation when using DBS for epilepsy [4].
- Ascending reticular activating system (ARAS) Tracts: The ARAS regulates arousal, alertness, and attention[5], and is composed of multiple nuclei and tracts, with only the medial forebrain bundle (MFB) and medial longitudinal fasciculus (MLF) depicted on this graphic.
References
- Lee DJ, Lozano CS, Dallapiazza RF, Lozano AM. Current and future directions of deep brain stimulation for neurological and psychiatric disorders. J Neurosurg. 2019 Aug 1;131(2):333-342. doi: 10.3171/2019.4.JNS181761. PMID: 31370011
- Chung S, Storey P, Shepherd TM, Lui YW. MR Susceptibility Imaging with a Short TE (MR-SISET): A Clinically Feasible Technique to Resolve Thalamic Nuclei. AJNR Am J Neuroradiol. 2020 Sep;41(9):1629-1631. doi: 10.3174/ajnr.A6683. Epub 2020 Jul 16. PMID: 32675340; PMCID: PMC7583092
- Ichinohe, N., & Shoumura, K. (1998). A di-synaptic projection from the superior colliculus to the head of the caudate nucleus via the centromedian-parafascicular complex in the cat: an anterograde and retrograde labeling study. Neuroscience Research, 32, 295-303
- Remore LG, Rifi Z, Nariai H, Eliashiv DS, Fallah A, Edmonds BD, Matsumoto JH, Salamon N, Tolossa M, Wei W, Locatelli M, Tsolaki EC, Bari AA. Structural connections of the centromedian nucleus of thalamus and their relevance for neuromodulation in generalized drug-resistant epilepsy: insight from a tractography study. Ther Adv Neurol Disord. 2023 Oct 10;16:17562864231202064
- Agashe S, Burkholder D, Starnes K, Van Gompel JJ, Lundstrom BN, Worrell GA, Gregg NM. Centromedian Nucleus of the Thalamus Deep Brain Stimulation for Genetic Generalized Epilepsy: A Case Report and Review of Literature. Front Hum Neurosci. 2022 May 20;16:858413. doi: 10.3389/fnhum.2022.858413. PMID: 35669200; PMCID: PMC9164300