Centromedian nucleus
In the
anatomy of the brain, the
centromedian nucleus, also known as the
centrum medianum, (
CM or
Cm-Pf) is a part of the
intralaminar nucleus (ILN) of the
thalamus. There are two centromedian nuclei arranged bilaterally.
It contains about 2000
neurons per cubic millimetre and has a volume of about 300 cubic millimetres with 600,000 neurons in total. It sends
nerve fibres to the
caudate,
putamen and
collateral fibres to the
cerebral cortex. It receives nerve fibres from the cerebral cortex,
vestibular nuclei,
globus pallidus,
superior colliculus,
reticular formation, and
spinothalamic tract.
Its physiological role involves
attention and
arousal, including control of the level of cortical activity. Some frequencies of extracellular electrical stimulation of the centromedian nucleus can cause
absence seizures (temporary loss of consciousness) although electrical stimulation can be of therapeutic use in intractable
epilepsy and
Tourette's syndrome.
General anaesthetics specifically suppress activity in the ILN, including the centromedian nucleus. Complete bilateral lesions of the centromedian nucleus can lead to states normally associated with
brain death such as
coma, death,
persistent vegetative state, forms of
mutism and
severe delirium. Unilateral lesions can lead to
unilateral thalamic neglect.
Furthermore, it has been suggested that the human consciousness resides fully or at least mainly in the centromedian nucleus.
*
The Global Thalamus (See level 12, the centromedian nucleus is labelled CM)*
Nicholas D. Schiff and Fred Plum. The Role of Arousal and "Gating" Systems in the Neurology of Impaired Consciousness. Journal of Clinical Neurophysiology. 17(5):438–452, 2000.*
J. M. Henderson, K. Carpenter, H. Cartwright and G. M. Halliday. Loss of thalamic intralaminar nuclei in progressive supranuclear palsy and Parkinson's disease: clinical and therapeutic implications. Brain, Vol. 123, No. 7, 1410-1421, July 2000*
Joe Bogen's Consciousness Page (Professor Bogen)
