#summary Biological Mind Tracts
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http://usvn.ahuman.org/svn/ahwiki/images/wiki/research/bio-research.jpg
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This page is intended to describe set of descending tracts

<wiki:toc max_depth="2" />

= Tract Details =
(generated)

TRACT SET: *Descending Tracts*

<img src="http://o.quizlet.com/OvyHXzkWIfq4piBE7gtbUw.png" alt="unavailable" style="max-width: 100%;">


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=== ATS - autonomic tracts system ===
  * external: 
  * synonyms: descending autonomic fibers
  * function:directs activity of glands, smooth muscles, and cardiac muscle
  * generic path: {cortex, HT, AM, RF} -> {sympathetic and parasympathetic}


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==== HTST - hypothalamospinal tract ====
  * external: http://en.wikipedia.org/wiki/Hypothalamospinal_tract
  * function:control autonomic components
  * comments: descend in dorsolateral funiculus; oculosympathetic pathway; next to superior cervical ganglion to common carotid - internal carotid - long ciliary nerves to pupillary dilator
  * notes to function: 
   * descend in dorsolateral funiculus
   *  oculosympathetic pathway
   *  next to superior cervical ganglion to common carotid - internal carotid - long ciliary nerves to pupillary dilator
  * generic path: {paraventrical nucleus of hypothalamus} -> {IML, sympathetic and parasympathetic preganglionic neurons; ciliospinal center of IML (T1,T2)}

<img src="http://instruct.uwo.ca/anatomy/530/autcont.gif" alt="unavailable" style="max-width: 100%;" height=400>


*Tract path details:*
  * path *HTST.CSC*: stress responses (from paraventricular and lateral hypohtalamus to IML and SPS) - [BrainRegionLAC_FD_HT_PV Paraventricular Nucleus,LAC.FD.HT.PV] -> [BrainRegionLAC_SC_IZ_CSC Ciliospinal Center,LAC.SC.IZ.CSC]
  * path *HTST.IML*: blood pressure regulation (from paraventricular and lateral hypohtalamus to IML and SPS) - [BrainRegionLAC_FD_HT_PV Paraventricular Nucleus,LAC.FD.HT.PV] -> [BrainRegionLAC_SC_IZ_IML Intermediolateral Nucleus,LAC.SC.IZ.IML]


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==== SSS - solitariospinal system ====
  * external: http://en.wikipedia.org/wiki/Respiratory_system
  * function:autonomic control of breathing
  * comments: respiratory, vomiting and micturition functions
  * notes to function: 
   * respiratory, vomiting and micturition functions
  * generic path: {ventrolateral solitary nucleus, retroambiguus nucleus} -> {diaphragm}

<img src="http://www.medicine.mcgill.ca/physio/resp-web/Fig_jpm/FIG5-5.jpg" alt="unavailable" style="max-width: 100%;">



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===== SSET - solitariospinal expiratory tract =====
  * external: http://en.wikipedia.org/wiki/Ventral_respiratory_group
  * function:facilitate expiratory motor neurons to intercostal muscles
  * comments: nucleus ambiguus - cranial division innervates muscles of the ipsilateral accessory muscles of respiration, principally via the vagus; nucleus retroambiguus - caudal division provides inspiratory and expiratory drive to the motor neurones of the intercostal muscles
  * notes to function: 
   * nucleus ambiguus - cranial division innervates muscles of the ipsilateral accessory muscles of respiration, principally via the vagus
   *  nucleus retroambiguus - caudal division provides inspiratory and expiratory drive to the motor neurones of the intercostal muscles
  * generic path: {parabrachial nucleus to nucleus ambiguus, nucleus retroambiguus} -> {internal intercostal muscles and abdominal muscles}

<img src="http://www.as.miami.edu/chemistry/2086/chap23/The%20Respiratory%20System%20Part%202_files/image009.jpg" alt="unavailable" style="max-width: 100%;">


*Tract path details:*
  * path *SSET.PATH*: facilitary expiratory muscles (descending in ventral funiculus) - [BrainRegionLPC_HL_AMB Ambiguus Nucleus,LPC.HL.AMB] -> [BrainRegionLPC_SC_VH_VM Ventromedial Nucleus,LPC.SC.VH.VM]


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===== SSIT - solitariospinal inpiratory tract =====
  * external: http://en.wikipedia.org/wiki/Dorsal_respiratory_group
  * function:facilitate inspiratory motor neurons in phrenic nucleus
  * comments: neck muscles, external intercostal muscles - conscious forced inspiration; pneumotaxic center = medial parabrachial nucleus + kolliker-fuse nucleus, breathing frequency
  * notes to function: 
   * neck muscles, external intercostal muscles - conscious forced inspiration
   *  pneumotaxic center = medial parabrachial nucleus + kolliker-fuse nucleus, breathing frequency
  * generic path: {kolliker-fuse nucleus, receptors to solitary nucleus} -> {phrenic nucleus, inspiratory; diaphragm}

<img src="http://what-when-how.com/wp-content/uploads/2012/04/tmp3611.jpg" alt="unavailable" style="max-width: 100%;" height=600>


*Tract path details:*
  * path *SSIT.PATH*: driving inspiratory muscles (descending in ventral part of lateral funiculus) - [BrainRegionLRC_HT_KFN Kolliker-Fuse Nucleus,LRC.HT.KFN] -> [BrainRegionLPC_SC_VH_PHR Phrenic Nucleus,LPC.SC.VH.PHR]


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=== ESS - extensor somatic system ===
  * external: 
  * function:control extensor muscles


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==== ACST - anterior corticospinal tract ====
  * external: http://en.wikipedia.org/wiki/Anterior_corticospinal_tract
  * synonyms: ventral corticospinal tract
  * function:extensor motor, pyramidal tract, conscious
  * comments: premotor BA 6, parietal BA 1,2,3
  * notes to function: 
   * premotor BA 6, parietal BA 1,2,3

<img src="http://www2.fiu.edu/~condon/cs-cb.jpg" alt="unavailable" style="max-width: 100%;">


*Tract path details:*
  * path *ACST.VL*: conscious control of distal extensors (premotor cortex to spinal cord VL) - [BrainRegionNMA_NC_PMC_F2 Dorsal Caudal Premotor Cortex,NMA.NC.PMC.F2] -> [BrainRegionLPC_SC_VH_VL Ventrolateral Nucleus,LPC.SC.VH.VL]
  * path *ACST.VM*: conscious control of axial extensors (premotor cortex to spinal cord VM) - [BrainRegionNMA_NC_SMC_F3 Supplementary Motor Area,NMA.NC.SMC.F3] -> [BrainRegionLPC_SC_VH_VM Ventromedial Nucleus,LPC.SC.VH.VM]


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==== MLFS - medial longitudinal fasciculus system ====
  * external: http://en.wikipedia.org/wiki/Medial_longitudinal_fasciculus
  * function:connects the cranial nerve nuclei III (oculomotor nerve), IV (trochlear nerve) and VI (abducens nerve) together, and integrates movements directed by the gaze centers (frontal eye field) and information about head movement (from cranial nerve VIII, vestibulocochlear nerve)
  * comments: connects together III, IV, and VI; integral component of saccadic eye movements as well as vestibulo-ocular and optokinetic reflexes; tectospinal and vestibulospinal
  * notes to function: 
   * connects together III, IV, and VI
   *  integral component of saccadic eye movements as well as vestibulo-ocular and optokinetic reflexes
   *  tectospinal and vestibulospinal
  * generic path: {vestibular nucleus} -> {}


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===== TCST - tectospinal tract =====
  * external: http://en.wikipedia.org/wiki/Tectospinal_tract
  * function:mediate reflex postural movements of head in response to visual and auditory stimuli
  * comments: extrapyramidal; in response to bright and sudden movements and loud noises
  * notes to function: 
   * extrapyramidal
   *  in response to bright and sudden movements and loud noises

<img src="http://www.neuroanatomy.wisc.edu/virtualbrain/Images/23C.jpg" alt="unavailable" style="max-width: 100%;" height=800>


*Tract path details:*
  * path *TCST.DEEP*: coordinates head and eye movements; mediate reflex postural movements of head in response to visual stimuli (from deep layers of the superior colliculus; projects to contralateral and ipsilateral portion of first cervical neuromeres of spinal cord, oculomotor and trochlear nuclei and abducens nucleus) - [BrainRegionLRC_MM_SC_DEEP Deep Superior Colliculus,LRC.MM.SC.DEEP] -> [BrainRegionLPC_SC_VH_SAN Spinal Accessory Nucleus,LPC.SC.VH.SAN]
  * path *TCST.INT*: coordinates head and eye movements; mediate reflex postural movements of head in response to auditory and somatosensory stimuli (from intermediate layers of the superior colliculus; projects to contralateral and ipsilateral portion of first cervical neuromeres of spinal cord, oculomotor and trochlear nuclei and abducens nucleus) - [BrainRegionLRC_MM_SC_DEEP Deep Superior Colliculus,LRC.MM.SC.DEEP] -> [BrainRegionLPC_SC_VH_SAN Spinal Accessory Nucleus,LPC.SC.VH.SAN]


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===== VST - vestibulospinal tract =====
  * external: http://en.wikipedia.org/wiki/Vestibulospinal_tract
  * function:alter muscle tone, extend, and change position of limbs and head with goal of supporting posture and maintaining balance of body and head; maintain balance and to stabilize the visual image on the retina during head movements
  * comments: extrapyramidal; proximal muscles, postural control; activates extensors, inhibits flexors; vestibular nuclei receive their primary input from the vestibular portion of C.N. VIII - vestibular-auditory
  * notes to function: 
   * extrapyramidal
   *  proximal muscles, postural control
   *  activates extensors, inhibits flexors
   *  vestibular nuclei receive their primary input from the vestibular portion of C.N. VIII - vestibular-auditory

<img src="http://www.neuroanatomy.wisc.edu/virtualbrain/Images/23D.jpg" alt="unavailable" style="max-width: 100%;">



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====== LVST - lateral vestibulospinal tract ======
  * external: http://en.wikipedia.org/wiki/Lateral_vestibulospinal_tract
  * function:maintain an upright and balanced posture by stimulating extensor motor neurons in legs
  * comments: also innervates muscles of the trunk, thus additionally aiding in body posture; lateral vestibular nuclei receive input from cerebellum
  * notes to function: 
   * also innervates muscles of the trunk, thus additionally aiding in body posture
   *  lateral vestibular nuclei receive input from cerebellum
  * generic path: {lateral vestibular nucleus; additional input from superior and inferior vestibular nuclei} -> {extensor muscles of legs}

<img src="http://www.neuroanatomy.wisc.edu/virtualbrain/Images/13F1.jpg" alt="unavailable" style="max-width: 100%;">


*Tract path details:*
  * path *LVST.PATH*: maintain an upright and balanced posture by stimulating extensor motor neurons in legs (originating in lateral, superior, and inferior vestibular nuclei (primarily the lateral); projects ipsilaterally down to lumbar region of spinal cord) - [BrainRegionLPC_HT_LVBN Lateral Vestibular Nucleus,LPC.HT.LVBN] -> [BrainRegionLPC_SC_VH_VL Ventrolateral Nucleus,LPC.SC.VH.VL]


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====== MVST - medial vestibulospinal tract ======
  * external: http://en.wikipedia.org/wiki/Medial_vestibulospinal_tract
  * function:controls position of the head, neck, and eyes in response to changes in posture
  * comments: controlling lower motor neurons associated with the spinal accessory nerve - CN XI; additionally, projects superiorly to the paramedian pontine reticular formation, indirectly innervating the nuclei of CN VI and III
  * notes to function: 
   * controlling lower motor neurons associated with the spinal accessory nerve - CN XI
   *  additionally, projects superiorly to the paramedian pontine reticular formation, indirectly innervating the nuclei of CN VI and III
  * generic path: {medial vestibular nucleus} -> {spinal accessory nucleus, paramedian pontine reticular formation; found only in cervical spine and above}

<img src="http://www.neuroanatomy.wisc.edu/virtualbrain/Images/13F.jpg" alt="unavailable" style="max-width: 100%;">


*Tract path details:*
  * path *MVST.PATH*: it controls head and whole body orientation (from medial vestibular nucleus; projects bilaterally down spinal cord and triggers ventral horn of cervical spinal circuits) - [BrainRegionLPC_HT_MVBN Medial Vestibular Nucleus,LPC.HT.MVBN] -> [BrainRegionLPC_SC_VH_SAN Spinal Accessory Nucleus,LPC.SC.VH.SAN]


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==== RTSS - reticulospinal system ====
  * external: http://en.wikipedia.org/wiki/Reticulospinal_tract
  * function:locomotion and postural control
  * comments: extrapyramidal; proximal muscles, postural control; integrates information from the motor systems to coordinate automatic movements of locomotion and posture; facilitates and inhibits voluntary movement; influences muscle tone; mediates autonomic functions; modulates pain impulses; influences blood flow to lateral geniculate nucleus of the thalamus
  * notes to function: 
   * extrapyramidal
   *  proximal muscles, postural control
   *  integrates information from the motor systems to coordinate automatic movements of locomotion and posture
   *  facilitates and inhibits voluntary movement
   *  influences muscle tone
   *  mediates autonomic functions
   *  modulates pain impulses
   *  influences blood flow to lateral geniculate nucleus of the thalamus

<img src="http://what-when-how.com/wp-content/uploads/2012/04/tmp14107.jpg" alt="unavailable" style="max-width: 100%;" height=600>



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===== MRST - medullary reticulospinal tract =====
  * external: 
  * synonyms: lateral reticulospinal tract
  * function:inhibiting excitatory axial extensor muscles of movement
  * generic path: {Gigantocellular Reticular Nucleus} -> {extensor muscles, all levels of spinal cord}

<img src="http://instruct.uwo.ca/anatomy/530/descmoto.gif" alt="unavailable" style="max-width: 100%;" height=600>


*Tract path details:*
  * path *RTSS.MGC*: coordinate with phasic movements to and from paradoxical sleep; inhibit with enkephalin (from nucleus reticularis gigantocellularis (vasodepressor center) to lamina VII) - [BrainRegionLRC_HL_PRF_GCR Gigantocellular Reticular Nucleus,LRC.HL.PRF.GCR] -> [BrainRegionLAC_SC_IZ_IML Intermediolateral Nucleus,LAC.SC.IZ.IML]


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===== PRST - pontine reticulospinal tract =====
  * external: 
  * synonyms: medial reticulospinal tract
  * function:exciting anti-gravity, extensor muscles; mediate postural adjustments in response to startling stimuli
  * generic path: {Pontine Reticular Formation } -> {extensor muscles, all levels of spinal cord}

<img src="http://what-when-how.com/wp-content/uploads/2012/04/tmp3624.jpg" alt="unavailable" style="max-width: 100%;" height=600>


*Tract path details:*
  * path *RTSS.PNC*: mediate head movement, suppresses muscle tone during REM sleep (from caudal pontine reticular nucleus to lamina VII and lamina VIII of spinal cord) - [BrainRegionLRC_HT_PRF_CRF Caudal Pontine Reticular Nucleus,LRC.HT.PRF.CRF] -> [BrainRegionLPC_SC_VH_VM Ventromedial Nucleus,LPC.SC.VH.VM]
  * path *RTSS.PNO*: coordinate with phasic movements to and from paradoxical sleep (from oral pontine reticular nucleus to lamina VII and lamina VIII of spinal cord) - [BrainRegionLRC_HT_PRF_RPO Oral Pontine Reticular Nucleus,LRC.HT.PRF.RPO] -> [BrainRegionLPC_SC_VH_VM Ventromedial Nucleus,LPC.SC.VH.VM]


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=== FSS - flexor somatic system ===
  * external: 
  * function:control flexor muscles


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==== CBT - corticobulbar tract ====
  * external: http://en.wikipedia.org/wiki/Corticobulbar_tract
  * function:carrying the motor function of the non-oculomotor cranial nerves
  * comments: V, VII, XI, and XII; indirectly - via IX and X in nucleus ambiguus
  * notes to function: 
   * V, VII, XI, and XII
   *  indirectly - via IX and X in nucleus ambiguus

<img src="http://usvn.ahuman.org/svn/ahwiki/images/wiki/research/biomodel/spinobulbar.jpg" alt="unavailable" style="max-width: 100%;" height=800>


*Tract path details:*
  * path *CBT.FACE*: conscious face expression (cortex to face muscles) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_HT_FCM Facial Motor Nucleus,LPC.HT.FCM]
  * path *CBT.MOUTH*: conscious jaw move (cortex to jaw muscles) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_HT_TRM Trigeminal Motor Nucleus,LPC.HT.TRM]
  * path *CBT.NECK*: conscious neck move (cortex to neck muscles) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_SC_VH_SAN Spinal Accessory Nucleus,LPC.SC.VH.SAN]
  * path *CBT.THROAT*: conscious pharynx/larynx move (cortex to throat muscles) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_HL_AMB Ambiguus Nucleus,LPC.HL.AMB]
  * path *CBT.TONGUE*: conscious tongue move (cortex to tongue muscles) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_HL_HYG Hypoglossal Motor Nucleus,LPC.HL.HYG]


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==== LSTT - lateral corticospinal tract ====
  * external: http://en.wikipedia.org/wiki/Lateral_corticospinal_tract
  * function:flexor motor, pyramidal tract, conscious; volitional skilled motor activity
  * comments: 90 percents of corticospinal fibers; 80 percents - contrallateral; 10 percents - unilateral; cervical-medial, thoracic, lumbar-lateral, distal muscles, decussating to contralateral and ipsilateral
  * notes to function: 
   * 90 percents of corticospinal fibers
   *  80 percents - contrallateral
   *  10 percents - unilateral
   *  cervical-medial, thoracic, lumbar-lateral, distal muscles, decussating to contralateral and ipsilateral
  * generic path: {cortex BA 1-4,6} -> {muscle groups that require concentration and conscious thought to control; upper limb digits}

<img src="http://www.ib.cnea.gov.ar/~redneu/2013/BOOKS/Principles%20of%20Neural%20Science%20-%20Kandel/gateway.ut.ovid.com/fulltextservice/ct%7B06b9ee1beed594190674f1983457a7dd32af6a0d5a4c9892~23/da4c18ff8.gif.png" alt="unavailable" style="max-width: 100%;" height=800>


*Tract path details:*
  * path *LCST.PL*: conscious control of proximal flexors (cortex to spinal cord PL) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_SC_VH_PL Posterolateral Nucleus,LPC.SC.VH.PL]
  * path *LCST.PM*: conscious control of axial flexors (cortex to spinal cord PM) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_SC_VH_PM Posteromedial Nucleus,LPC.SC.VH.PM]
  * path *LCST.RPL*: conscious control of distal flexors (cortex to spinal cord RPL) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainRegionLPC_SC_VH_RPL Retroposterolateral Nucleus,LPC.SC.VH.RPL]


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==== RBST - rubrospinal tract ====
  * external: http://en.wikipedia.org/wiki/Rubrospinal_tract
  * function:mediation of voluntary movement, upper limbs; control of flexor tone
  * comments: extrapyramidal; activates flexors, inhibits extensors; pattern locomotion, inhibit reflex activity in spinal cord; terminate into dorsal horn and in the intermediate region of the ventral horn; fibers terminated in contralateral laminae 5, 6, and the dorsal part of lamina 7 at all spinal cord levels
  * notes to function: 
   * extrapyramidal
   *  activates flexors, inhibits extensors
   *  pattern locomotion, inhibit reflex activity in spinal cord
   *  terminate into dorsal horn and in the intermediate region of the ventral horn
   *  fibers terminated in contralateral laminae 5, 6, and the dorsal part of lamina 7 at all spinal cord levels

<img src="http://www.neuroanatomy.wisc.edu/virtualbrain/Images/22B.jpg" alt="unavailable" style="max-width: 100%;" height=600>


*Tract path details:*
  * path *RBST.CR*: automatic control of flexors (cerebellum to red nucleus) - Cerebellum,LLC.HT.CR ([BrainRegionLRC_HT_CR_FN Cerebellar Flocconodular Lobe] (LRC.HT.CR.FN), [BrainRegionLLC_HT_CR_CC Cerebellar Lateral Lobe] (LLC.HT.CR.CC), [BrainRegionLLC_HT_CR_PV Cerebellar Paravermis] (LLC.HT.CR.PV), [BrainRegionLRC_HT_CR_VM Cerebellar Vermis] (LRC.HT.CR.VM)) -> [BrainCenterLLC_MM_RD Red Nucleus,LLC.MM.RD]
  * path *RBST.MC*: conscious modulation of automatic flexors activity (cortex to red nucleus) - [BrainRegionNMA_NC_MC Motor Cortex,NMA.NC.MC] -> [BrainCenterLLC_MM_RD Red Nucleus,LLC.MM.RD]
  * path *RBST.PL*: automatic control of proximal flexors (red nucleus to spinal cord PL) - [BrainCenterLLC_MM_RD Red Nucleus,LLC.MM.RD] -> [BrainRegionLPC_SC_VH_PL Posterolateral Nucleus,LPC.SC.VH.PL]
  * path *RBST.PM*: automatic control of axial flexors (red nucleus to spinal cord PM) - [BrainCenterLLC_MM_RD Red Nucleus,LLC.MM.RD] -> [BrainRegionLPC_SC_VH_PM Posteromedial Nucleus,LPC.SC.VH.PM]
  * path *RBST.RPL*: automatic control of distal flexors (red nucleus to spinal cord RPL) - [BrainCenterLLC_MM_RD Red Nucleus,LLC.MM.RD] -> [BrainRegionLPC_SC_VH_RPL Retroposterolateral Nucleus,LPC.SC.VH.RPL]