In the anatomy

Anatomy

Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...

 of the brain, the centromedian nucleus, also known as the centrum medianum, (CM or Cm-Pf) is a part of the intralaminar nucleus

Intralaminar nucleus

The intralaminar nucleus is a nucleus of the thalamus that contains the following nuclei:* central lateral* centromedian * paracentral* parafascicular.Some sources also include a "central dorsal" nucleus....

 (ILN) of the thalamus

Thalamus

The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...

. There are two centromedian nuclei arranged bilaterally.

It contains about 2000 neuron

Neuron

A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...

s per cubic millimetre and has a volume of about 310 cubic millimetres with 664,000 neurons in total.

Input and output

It sends nerve fibres to the subthalamic nucleus

Subthalamic nucleus

The subthalamic nucleus is a small lens-shaped nucleus in the brain where it is, from a functional point of view, part of the basal ganglia system. Anatomically, it is the major part of subthalamus. As suggested by its name, the subthalamic nucleus is located ventral to the thalamus. It is also...

 and putamen

Putamen

The putamen is a round structure located at the base of the forebrain . The putamen and caudate nucleus together form the dorsal striatum. It is also one of the structures that comprises the basal ganglia. Through various pathways, the putamen is connected to the substantia nigra and globus pallidus...

. It receives nerve fibres from the cerebral cortex, vestibular nuclei

Vestibular nuclei

The vestibular nuclei are the cranial nuclei for the vestibular nerve.In Terminologia Anatomica they are grouped in both the pons and medulla.-Subnuclei:There are 4 subnuclei; they are situated at the floor of the fourth ventricle....

, globus pallidus

Globus pallidus

The globus pallidus also known as paleostriatum, is a sub-cortical structure of the brain. Topographically, it is part of the telencephalon, but retains close functional ties with the subthalamus - both of which are part of the extrapyramidal motor system...

, superior colliculus

Superior colliculus

The optic tectum or simply tectum is a paired structure that forms a major component of the vertebrate midbrain. In mammals this structure is more commonly called the superior colliculus , but, even in mammals, the adjective tectal is commonly used. The tectum is a layered structure, with a...

, reticular formation

Reticular formation

The reticular formation is a part of the brain that is involved in actions such as awaking/sleeping cycle, and filtering incoming stimuli to discriminate irrelevant background stimuli...

, and spinothalamic tract

Spinothalamic tract

The spinothalamic tract is a sensory pathway originating in the spinal cord. It transmits information to the thalamus about pain, temperature, itch and crude touch...

.

Function

Its physiological role involves attention

Attention

Attention is the cognitive process of paying attention to one aspect of the environment while ignoring others. Attention is one of the most intensely studied topics within psychology and cognitive neuroscience....

 and arousal

Arousal

Arousal is a physiological and psychological state of being awake or reactive to stimuli. It involves the activation of the reticular activating system in the brain stem, the autonomic nervous system and the endocrine system, leading to increased heart rate and blood pressure and a condition of...

, including control of the level of cortical activity. Some frequencies of extracellular electrical stimulation of the centromedian nucleus can cause absence seizure

Absence seizure

Absence seizures are one of several kinds of seizures. These seizures are sometimes referred to as petit mal seizures ....

s (temporary loss of consciousness) although electrical stimulation can be of therapeutic use in intractable epilepsy

Epilepsy

Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...

 and Tourette's syndrome

Tourette syndrome

Tourette syndrome is an inherited neuropsychiatric disorder with onset in childhood, characterized by multiple physical tics and at least one vocal tic; these tics characteristically wax and wane...

. General anaesthetic

General anaesthetic

A general anaesthetic is a drug that brings about a reversible loss of consciousness. These drugs are generally administered by an anaesthesia provider to induce or maintain general anaesthesia to facilitate surgery...

s 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

Brain death

Brain death is the irreversible end of all brain activity due to total necrosis of the cerebral neurons following loss of brain oxygenation. It should not be confused with a persistent vegetative state...

 such as coma

Coma

In medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...

, death, persistent vegetative state

Persistent vegetative state

A persistent vegetative state is a disorder of consciousness in which patients with severe brain damage are in a state of partial arousal rather than true awareness. It is a diagnosis of some uncertainty in that it deals with a syndrome. After four weeks in a vegetative state , the patient is...

, forms of mutism and severe delirium. Unilateral lesions can lead to unilateral thalamic neglect.

Some have suggested the controversial notion that human consciousness

Consciousness

Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...

 resides fully or at least mainly in the centromedian nucleus, since damage or change to the area alters consciousness significantly.

External links

- The Global Thalamus (See level 12, the centromedian nucleus is labelled CM)

• Joe Bogen's Consciousness Page (Professor Bogen) at California Institute of Technology
  California Institute of Technology
  The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...
  
  
• NIF Search - Centromedian Nucleus via the Neuroscience Information Framework
  Neuroscience Information Framework
  The Neuroscience Information Framework is a repository of global neuroscience web resources, including experimental, clinical, and translational neuroscience databases, knowledge bases, atlases, and genetic/genomic resources.-Description:...