Dorsal trigeminal tract

Dorsal trigeminal tract
Details
Identifiers
Latin	tractus trigeminothalamicus posterior
NeuroNames	606
NeuroLex ID	birnlex_1718
TA98	A14.1.05.312
TA2	5864
FMA	72500
Anatomical terms of neuroanatomy [edit on Wikidata]

The dorsal trigeminal tract (also dorsal trigeminothalamic tract, or posterior trigeminothalamic tract) are uncrossed second-order sensory fibers conveying fine (discriminative) touch and pressure information from the dorsomedial division of principal sensory nucleus of trigeminal nerve to the ipsilateral ventral posteromedial nucleus of thalamus. Second-order fibers from the ventrolateral division of the principal sensory nucleus meanwhile cross-over to ascend contralaterally in the ventral trigeminal tract along with those fibers arising from the spinal trigeminal nucleus.^[1]

The DTT may be likened functionally to the medial lemniscus.^[2]

Trigeminal ganglion → first-order neurons → dorsomedial division of principal sensory nucleus of trigeminal nerve (in pons) (synapse) → second-order neurons → trigeminal lemniscus (in midbrain) → (ipsilateral) ventral posteromedial nucleus of the thalamus (synapse) → third-order neurons → sensory cortex of postcentral gyrus (synapse)

References

^ Patestas, Maria A.; Gartner, Leslie P. (2016). A Textbook of Neuroanatomy (2nd ed.). Hoboken, New Jersey: Wiley-Blackwell. p. 329. ISBN 978-1-118-67746-9.
^ Siegel, Allan; Sapru, Hreday N.; Siegel, Heidi (2015). Essential Neuroscience (3rd ed.). Philadelphia: Wolters Kluwer Health. p. 229. ISBN 978-1-4511-8968-1.

External links

Trigeminothalamic tracts (Netter image)
http://www.medilexicon.com/medicaldictionary.php?t=48738 Archived 2013-06-03 at the Wayback Machine

Anatomy of the pons

Dorsal/
(tegmentum)

Surface

White: Sensory

Trapezoid body
Trigeminal lemniscus
- Dorsal trigeminal tract
- Ventral trigeminal tract
Medial lemniscus
Lateral lemniscus
Central tegmental tract
Medial longitudinal fasciculus
- Vestibulo-oculomotor fibers

White: Motor

Grey: Cranial nuclei

afferent:	GSA Trigeminal Principal Spinal Cochlear nucleus Dorsal Anterior Vestibular nuclei Superior
efferent:	SVE: Trigeminal motor nucleus Facial motor nucleus GSE: Abducens nucleus GVE: Superior salivary nucleus Inferior salivary nucleus

Grey: Other nuclei

Ventral/
(base)

Grey	Pontine nuclei
White: Motor/descending	Corticospinal tract Corticobulbar tract Corticopontine fibers MCP Pontocerebellar fibers
Surface	Basilar sulcus

Other grey: Raphe/
reticular

Brain and spinal cord: neural tracts and fasciculi

Sensory

DCML

1°:	Pacinian corpuscle/Meissner's corpuscle → Posterior column (Gracile fasciculus/Cuneate fasciculus) → Gracile nucleus/Cuneate nucleus
2°:	→ sensory decussation/arcuate fibers (Posterior external arcuate fibers, Internal arcuate fibers) → Medial lemniscus/Trigeminal lemniscus → Thalamus (VPL, VPM)
3°:	→ Posterior limb of internal capsule → Postcentral gyrus

Anterolateral/
pain

Fast/lateral	1° (Free nerve ending → A delta fiber) → 2° (Anterior white commissure → Lateral and Anterior Spinothalamic tract → Spinal lemniscus → VPL of Thalamus) → 3° (Postcentral gyrus) → 4° (Posterior parietal cortex) 2° (Spinomesencephalic tract → Superior colliculus of Midbrain tectum)
Slow/medial	1° (Group C nerve fiber → Spinoreticular tract → Reticular formation) → 2° (MD of Thalamus) → 3° (Cingulate cortex)

Motor

Pyramidal

flexion: Primary motor cortex → Posterior limb of internal capsule → Decussation of pyramids → Corticospinal tract (Lateral, Anterior) → Neuromuscular junction

Extrapyramidal

flexion:	Primary motor cortex → Genu of internal capsule → Corticobulbar tract → Facial motor nucleus → Facial muscles
flexion:	Red nucleus → Rubrospinal tract
extension:	Vestibulocerebellum → Vestibular nuclei → Vestibulospinal tract
extension:	Vestibulocerebellum → Reticular formation → Reticulospinal tract
Midbrain tectum → Tectospinal tract → muscles of neck

Basal ganglia

direct:	1° (Motor cortex → Striatum) → 2° (GPi) → 3° (Lenticular fasciculus/Ansa lenticularis → Thalamic fasciculus → VL of Thalamus) → 4° (Thalamocortical radiations → Supplementary motor area) → 5° (Motor cortex)
indirect:	1° (Motor cortex → Striatum) → 2° (GPe) → 3° (Subthalamic fasciculus → Subthalamic nucleus) → 4° (Subthalamic fasciculus → GPi) → 5° (Lenticular fasciculus/Ansa lenticularis → Thalamic fasciculus → VL of Thalamus) → 6° (Thalamocortical radiations → Supplementary motor area) → 7° (Motor cortex)
nigrostriatal pathway:	Pars compacta → Striatum

Cerebellar

Afferent

Vestibular nuclei → Vestibulocerebellar tract → ICP → Cerebellum → Granule cell

Pontine nuclei → Pontocerebellar fibers → MCP → Deep cerebellar nuclei → Granule cell

Inferior olivary nucleus → Olivocerebellar tract → ICP → Hemisphere → Purkinje cell → Deep cerebellar nuclei

Efferent

Dentate nucleus in Lateral hemisphere/pontocerebellum → SCP → Dentatothalamic tract → Thalamus (VL) → Motor cortex

Interposed nucleus in Intermediate hemisphere/spinocerebellum → SCP → Reticular formation, or → Cerebellothalamic tract → Red nucleus → Thalamus (VL) → Motor cortex

Fastigial nucleus in Flocculonodular lobe/vestibulocerebellum → Vestibulocerebellar tract → Vestibular nuclei

Bidirectional:
Spinocerebellar

Unconscious proprioception	lower limb → 1° (muscle spindles → DRG) → 2° (Posterior thoracic nucleus → Dorsal/posterior spinocerebellar tract → ICP → Cerebellar vermis) upper limb → 1° (muscle spindles → DRG) → 2° (Accessory cuneate nucleus → Cuneocerebellar tract → ICP → Anterior lobe of cerebellum)
Reflex arc	lower limb → 1° (Golgi tendon organ) → 2° (Ventral/anterior spinocerebellar tract→ SCP → Cerebellar vermis) upper limb → 1° (Golgi tendon organ) → 2° (Rostral spinocerebellar tract → ICP → Cerebellum)

Anatomy of the midbrain

Tectum
(Dorsal)

Corpora quadrigemina

Grey matter

Pretectal area

White matter

Sensory / ascending	Spinotectal tract Central tegmental tract
Motor / descending	Tectospinal tract

CSF

Cerebral aqueduct

Peduncle
(Ventral)

Tegmentum

White matter

Sensory / ascending	Lemnisci Medial Lateral Ascending MLF Vestibulo-oculomotor fibers Spinothalamic tract Anterior trigeminothalamic tract Dentatothalamic tract
Motor / descending	Rubrospinal tract Rubro-olivary tract Descending MLF

Grey matter

cranial nuclei	GSA Mesencephalic GSE Oculomotor nucleus Trochlear nucleus GVE Edinger–Westphal nucleus
Ventral tegmental area	Rostromedial tegmental nucleus
Periaqueductal gray Red nucleus Rostral interstitial nucleus of medial longitudinal fasciculus Parabrachial area Interpeduncular nucleus
Midbrain reticular formation	dorsal tegmental nucleus Raphe nuclei dorsal Reticulotegmental nucleus

Base

White / Cerebral crus	Corticospinal tract Corticobulbar tract Corticopontine tract Frontopontine fibers Temporopontine fibers
Grey / Substantia nigra	Pars compacta Pars reticulata
Surface	Superior cerebellar peduncle Decussation Interpeduncular fossa

Anatomy of the diencephalon of the human brain

Epithalamus

Surface	Pineal gland Habenula Habenular trigone Habenular commissure
Grey matter	Pretectal area Habenular nuclei Subcommissural organ

Thalamus

Surface	Stria medullaris of thalamus Thalamic reticular nucleus Taenia thalami
Grey matter/ nuclei	paired: AN Ventral VA/VL VP/VPM/VPL Lateral LD LP Pulvinar nuclei Metathalamus MG LG P cell M cell K cell midline: MD Intralaminar Centromedian Midline nuclear group Interthalamic adhesion
White matter	Mammillothalamic tract Pallidothalamic tracts Ansa lenticularis Lenticular fasciculus Thalamic fasciculus PCML Medial lemniscus Trigeminal lemniscus Spinothalamic tract Lateral lemniscus Dentatothalamic tract Acoustic radiation Optic radiation Subthalamic fasciculus Anterior trigeminothalamic tract Medullary laminae

Hypothalamus

Surface

Grey matter

Autonomic zones	Anterior (parasympathetic/heat loss) Posterior (sympathetic/heat conservation)
Endocrine	posterior pituitary: Paraventricular Magnocellular neurosecretory cell Parvocellular neurosecretory cell Supraoptic oxytocin/vasopressin other: Arcuate (dopamine/GHRH) Preoptic (GnRH) Suprachiasmatic (melatonin)
Emotion	Lateral Ventromedial Dorsomedial

White matter

afferent
efferent
- Mammillothalamic tract
- Dorsal longitudinal fasciculus

Pituitary

Posterior is diencephalon, but anterior is glandular

Subthalamus

Brain and spinal cord: neural tracts and fasciculi

Sensory

DCML

1°:	Pacinian corpuscle/Meissner's corpuscle → Posterior column (Gracile fasciculus/Cuneate fasciculus) → Gracile nucleus/Cuneate nucleus
2°:	→ sensory decussation/arcuate fibers (Posterior external arcuate fibers, Internal arcuate fibers) → Medial lemniscus/Trigeminal lemniscus → Thalamus (VPL, VPM)
3°:	→ Posterior limb of internal capsule → Postcentral gyrus

Anterolateral/
pain

Fast/lateral	1° (Free nerve ending → A delta fiber) → 2° (Anterior white commissure → Lateral and Anterior Spinothalamic tract → Spinal lemniscus → VPL of Thalamus) → 3° (Postcentral gyrus) → 4° (Posterior parietal cortex) 2° (Spinomesencephalic tract → Superior colliculus of Midbrain tectum)
Slow/medial	1° (Group C nerve fiber → Spinoreticular tract → Reticular formation) → 2° (MD of Thalamus) → 3° (Cingulate cortex)

Motor

Pyramidal

flexion: Primary motor cortex → Posterior limb of internal capsule → Decussation of pyramids → Corticospinal tract (Lateral, Anterior) → Neuromuscular junction

Extrapyramidal

flexion:	Primary motor cortex → Genu of internal capsule → Corticobulbar tract → Facial motor nucleus → Facial muscles
flexion:	Red nucleus → Rubrospinal tract
extension:	Vestibulocerebellum → Vestibular nuclei → Vestibulospinal tract
extension:	Vestibulocerebellum → Reticular formation → Reticulospinal tract
Midbrain tectum → Tectospinal tract → muscles of neck

Basal ganglia

direct:	1° (Motor cortex → Striatum) → 2° (GPi) → 3° (Lenticular fasciculus/Ansa lenticularis → Thalamic fasciculus → VL of Thalamus) → 4° (Thalamocortical radiations → Supplementary motor area) → 5° (Motor cortex)
indirect:	1° (Motor cortex → Striatum) → 2° (GPe) → 3° (Subthalamic fasciculus → Subthalamic nucleus) → 4° (Subthalamic fasciculus → GPi) → 5° (Lenticular fasciculus/Ansa lenticularis → Thalamic fasciculus → VL of Thalamus) → 6° (Thalamocortical radiations → Supplementary motor area) → 7° (Motor cortex)
nigrostriatal pathway:	Pars compacta → Striatum

Cerebellar

Afferent

Vestibular nuclei → Vestibulocerebellar tract → ICP → Cerebellum → Granule cell

Pontine nuclei → Pontocerebellar fibers → MCP → Deep cerebellar nuclei → Granule cell

Inferior olivary nucleus → Olivocerebellar tract → ICP → Hemisphere → Purkinje cell → Deep cerebellar nuclei

Efferent

Dentate nucleus in Lateral hemisphere/pontocerebellum → SCP → Dentatothalamic tract → Thalamus (VL) → Motor cortex

Interposed nucleus in Intermediate hemisphere/spinocerebellum → SCP → Reticular formation, or → Cerebellothalamic tract → Red nucleus → Thalamus (VL) → Motor cortex

Fastigial nucleus in Flocculonodular lobe/vestibulocerebellum → Vestibulocerebellar tract → Vestibular nuclei

Bidirectional:
Spinocerebellar

Unconscious proprioception	lower limb → 1° (muscle spindles → DRG) → 2° (Posterior thoracic nucleus → Dorsal/posterior spinocerebellar tract → ICP → Cerebellar vermis) upper limb → 1° (muscle spindles → DRG) → 2° (Accessory cuneate nucleus → Cuneocerebellar tract → ICP → Anterior lobe of cerebellum)
Reflex arc	lower limb → 1° (Golgi tendon organ) → 2° (Ventral/anterior spinocerebellar tract→ SCP → Cerebellar vermis) upper limb → 1° (Golgi tendon organ) → 2° (Rostral spinocerebellar tract → ICP → Cerebellum)