Substantia nigra

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Brain: Substantia nigra
Section through superior colliculus showing path of oculomotor nerve.
Coronal slices of human brain showing the basal ganglia, globus pallidus: external segment (GPe), subthalamic nucleus (STN), globus pallidus: internal segment (GPi), and substantia nigra (SN, red). The right section is the deeper one, closer to the back of the head.
Gray's	subject #188 802
Part of	Midbrain, Basal ganglia
NeuroNames	hier-527
MeSH	Substantia+Nigra

The substantia nigra (Latin for "black substance", Sömmering) or locus niger is a heterogeneous portion of the midbrain, separating the pes (foot) from the tegmentum (covering), and an accessory to the basal ganglia system.

Contents 1 Components 2 Additional images 3 See also 4 References 5 External links

[edit] Components

It consists of two strongly contrasted ensembles, the pars compacta and adjacent dopaminergic groups, and another ensemble made up of the pars reticulata and the pars lateralis. The latter two, along with the pallidal nuclei, are elements of the core of the basal ganglia. Although intricate and interconnected, the two ensembles must imperatively be distinguished.

The substantia nigra compacta and surrounding is responsible for dopamine production in the brain, and therefore plays a vital role in reward and addiction.

[edit] Additional images

Schematic representation of the chief ganglionic categories (I to V).	Deep dissection of brain-stem. Lateral view.	Deep dissection of brain-stem. Ventral view.	Coronal section through mid-brain.
Transverse section of mid-brain at level of inferior colliculi.	Transverse section of mid-brain at level of superior colliculi.	Coronal section of brain immediately in front of pons.	Human brain frontal (coronal) section
Dopamine and serotonin

[edit] See also

• Basal ganglia
• Brain stem
• Cerebral peduncle
• Dopamine
• Mesencephalon
• List of regions in the human brain
• Parkinson's disease

[edit] References

[edit] External links

• Brainstem at UWisc 20Substantia
• BrainMaps at UCDavis substantia nigra

• Diagram at uni-tuebingen.de
• Diagram and explanation of cortico-basal pathways

v • d • e Brain: mesencephalon (midbrain) Tectum (Dorsal) Corpora quadrigemina: Inferior colliculi (Brachium of inferior colliculus), Superior colliculi (Brachium of superior colliculus) Subcommissural organ • Pretectum Peduncle (Ventral) Peduncle tegmentum Periaqueductal gray (Cerebral aqueduct, Dorsal raphe nucleus) Ventral tegmentum • Pedunculopontine nucleus • Red nucleus (Rubrospinal tract, Rubro-olivary tract)  • MLF (riMLF)  • lemnisci (Medial, Lateral) cranial nuclei: GSA (V: Mesencephalic) - GSE (III: Oculomotor, IV: Trochlear) - GVE (III: Edinger-Westphal) Interstitial cell of Cajal Superior cerebellar peduncles (Decussation of superior cerebellar peduncle) Peduncle base Substantia nigra (Pars compacta, Pars reticulata) Cerebral crus: Corticospinal tract - Corticobulbar tract - Corticopontine tract/Frontopontine fibers/Temporopontine fibers Interpeduncular fossa

v • d • e Brain - Basal ganglia Rostral, telencephalon (corpus striatum) striatum: Putamen - Caudate nucleus lentiform nucleus: Putamen - Globus pallidus (GPe, GPi) Caudal, diencephalon Subthalamic nucleus Caudal, mesencephalon Substantia nigra (Pars compacta, Pars reticulata) Paths direct: Motor cortex → Striatum → GPi → Subthalamic fasciculus → Thalamus → Motor cortex indirect: Motor cortex → Striatum → GPe → Subthalamic nucleus → GPi → Subthalamic fasciculus → Thalamus → Motor cortex nigrostriatal pathway: Pars compacta → Striatum note: nucleus accumbens, claustrum and amygdala are considered part of basal ganglia by some sources