The intralaminar thalamic nuclei (ITN) are collections of

neuron A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...

s in the internal medullary lamina of the

thalamus The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of ...

.Mancall, E., Brock, D. & Gray, H. (2011). Gray's clinical neuroanatomy the anatomic basis for clinical neuroscience. Philadelphia: Elsevier/Saunders.

Anatomy

Structure

The ITN are generally divided in two groups as follows: * anterior (rostral) group **

central lateral nucleus In the human brain, the central lateral nucleus is a part of the anterior intralaminar nucleus in the thalamus. The intralaminar nuclei project to many different regions of the brain, The thalamus The thalamus (: thalami; from Greek language ...

** central medial nucleus (''not'' referred to as "centromedial"NeuroName 321
/ref>) ** paracentral nucleus * posterior (caudal) intralaminar group **

centromedian nucleus In the anatomy of the brain, the centromedian nucleus, also known as the centrum medianum, (CM or Cm-Pf) is a nucleus in the posterior group of the intralaminar thalamic nuclei (ITN) in the thalamus. (This must not be confused with the central me ...

** parafascicular nucleus Some sources also include a "central dorsal" nucleus.

Afferents

Midline intralaminar nuclei receive afferents from the brain stem, spinal cord, and cerebellum. Connections with the cerebral cortex and basal nuclei are reciprocal. Afferents from the

spinothalamic tract The spinothalamic tract is a nerve tract in the anterolateral system in the spinal cord. This tract is an ascending sensory pathway to the thalamus. From the ventral posterolateral nucleus in the thalamus, sensory information is relayed upwar ...

as well as

periaqueductal gray The periaqueductal gray (PAG), also known as the central gray, is a brain region that plays a critical role in autonomic function, motivated behavior and behavioural responses to threatening stimuli. PAG is also the primary control center for ...

are part of a pathway involved in pain processing.

Efferents

The intralaminar nuclei project efferents to the hypothalamus, amygdala, and limbic lobe.

Function

The ITN are thought to be involved in mediating arousal, affective, autonomic responses to pain.

Clinical significance

Degeneration of this area may occur in

progressive supranuclear palsy Progressive supranuclear palsy (PSP) is a late-onset neurodegenerative disease involving the gradual deterioration and death of specific volumes of the brain, linked to 4-repeat tau pathology. The condition leads to symptoms including Balance di ...

and

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become ...

Research

This area is also prominently affected in traumatic brain injuries. One postmortem study of patients with closed head injuries showed correlation of the involvement of these nuclei with the various degrees of disability.

References

External links

Diagram
at

University of Florida The University of Florida (Florida or UF) is a public university, public land-grant university, land-grant research university in Gainesville, Florida, United States. It is a senior member of the State University System of Florida and a preem ...

Thalamic nuclei {{neuroanatomy-stub