1. Intro to nervous system David Kachlík a Petr Zach

2. Nervous tissue cells parcellation Two types of cells: neurons – cells transmitting informations Glial cells (neuroglia, glia) (neuroglia) – neuronal support, protection and participation in their nutrition and work –astrocytes (astrocytus) –oligodendrocytes (oligodendrocytus) –microglia (microgliocytus) –ependymal cells (ependymocytus)

3. Nerves Are formed by clusters of nervous fibers Nerve fibers have covering similarly to muscular tissue: –endoneurium Layer of reticular fibers around individual nerve fibers –perineurium „sleeve“ containing bundles of nerve fibers formed by layers of epiteloid cells Numerous zonulae occludentes – non-passable barrier shielding nerve fibers –epineurium Fibrous covering of whole nerve

4. Nerves

5. Ganglias Nerve ganglias are accumulation of pericaryons in PNS They have ovoid shape and their surface is covered by capsule from thick non-organized fibrous tissue Typical are satellite cells (gliocyti ganglionici) – small cuboid cells surrounding perikarya of neurons http://en.wikipedia.org/wiki/Dorsal_root_ganglionhttp://www.pharmainfo.net/introduction-autonomic-nervous-system/classification

6. Ganglias - dichotomization Spinal ganglia (ganglion spinale) –sensory (ganglion sensorium) –In posteroir roots of spinal nerves and in the course of cranial nerves (V, IX, X) –Contain typical pseudounipolar neurons –Carry sensory impulses from periphery into CNS autonomous (vegetative) ganglias (ganglion autonomicum) –In the course of autonomic nerves –Contain multipolar neurons –Layer of satellite cells is incomplete –Intramural ganglias Parasympatetic ganglias in the wall of hollow organs

7. Development of neural tube Nervous tissue develops from neuroectoderm Neuroectoderm originates from ectoderm by notochord induction  neural plate  in the neurulation process creates neural tube=foundation of CNS Remnant of neuroectoderm separates  neural crest (crista neuralis) = foundation of PNS and other structures (ectomezenchyme of the head etc.)

9. Development of neural tube Primary neurulation –Separates ectoderm into three cell types Inside oriented neural tube epidermis externally Cells of neural crest Secondary neurulation –Cells of neural plate create chorda dorsalis In the course of 35th somite formation

10. Development of neural tube Epitelium of neural tube soon changes into multi layer neuroepitelium in which are created 3 layers: internal (germinal) zone (zona ventricularis; matrix germinalis) –Until half of intrauterine life fast proliferating (origination of neuroblasts) –Then reduction into ependyme Middle (shell) zone (zona intermedia; zona pallii) –Formed mostly by migrating neuroblasts –Grey matter originates from it External (marginal) zone (zona marginalis) –Formed by extenstions of neuroblasts –White matter originates from it

11. Development of neural tube

12. Somite (somitus) somitomers around 3rd week At the end of 5th week 42-44 somites http://www.aps.uoguelph.ca/~swatland/HTML10234/LEC5/LEC5.html http://www.uprightape.net/Image_Pages/UA_Fig7-4_SomiteDevel.html

13. Myotome Central part of primitive segment Starting 4th week during differentiation it retains lastly epiteloid organization Foundation of skeletal muscles

14. Sclerotome Dorzomedial part of primitive segment At the 4th week gains chars of mesenchyme Getting thicker around chorda dorsalis Creates foundation of axial skeleton (vertebras, costas, sternum) and base of skull

15. Ventrolateral part of primitive segment During differentiation from start of 4th week of development gains mesenchyme char Migrates into somatopleura Give foundation to fibrous part of skin (dermis and tela subcutanea) Parts originating from the same dermatome have nerve supply from one spinal rootDermatome

17. Composition of brain tissue Grey matter (substantia grisea) –pericarya of neurons, mostly non myelinated nerve fibers –Protoplazmic astrocytes, oligodendrocytes and microglia White matter (substantia alba) –Mostly myelinated fibers –Fibrilary astrocytes, oligodendrocytes and microglia http://library.med.utah.edu/WebPath/HISTHTML/NEURANAT/CNS230A.htmlhttp://fuckyeahnervoussystem.tumblr.com/post/1276369326/spinal-cord-light-micrograph-of-a-cross-section

18. CNS description- parts Spinal cord (Medulla spinalis) Brain stem (Truncus encephali) –Oblongate (Medulla oblongata) –Pons (Pons) – formerly pons Varoli –Midbrain (Mesencephalon) Small brain (Cerebellum) Diencephalon (Diencephalon) Forebrain (Telencephalon) –Basal ganglia (nuclei basales) –Brain cortex (cortex cerebri)

19. Telencephalon Diencephalon Mesencephalon Pons Medulla oblongata Medulla spinalis Cerebellum

20. CNS description Inside CNS cavities –4th ventricle, 3rd ventricle and two lateral ventricles CNS covered by meninges: –Hard meninge (pachymeninx = dura mater) –Soft meninge (leptomeninx) arachnoid (arachnoidea mater) pia (pia mater) Inside ventricles is cerebrospinal fluid (liquor cerebrospinalis = CSF) http://faculty.irsc.edu/FACULTY/TFischer/AP1/AP%201%20resources.htm http://mortdev.blogspot.cz/2008/09/brain-autopsy.html

22. CNS functions Spinal cord – reflexes, ascending and descending tracts Brain stem – vitally important reflexes (respiratory, cardiovascular, vomiting, coughing, synchronization of eyeball movement) diencephalon – hormonal production, circadian rhytms, termoregulation, food intake, autonomic regulation Terminal brain –cortex: functional cortical areas –Basal ganglia: movement patterns limbic system – behavior, emotions, memory

24. Brain stem Converting all ascending and descending nerve tracts (tractus) Reticular formation (RF; formatio reticularis) –Vital reflex centers Cardiac activity, respiration, vazomotorics, consciousness Nuclei of cranial nerves –n. III - XII

25. Mesencephalon Pons Medulla oblongata Medulla spinalis

26. Truncus encephali Medulla oblongata = oblongate Pons (Varoli) = pons Mesencephalon = mid brain Cavities of brain stem ventriculus quartus = 4th ventricle –fossa rhomboidea = bottom of 4th ventricle aqueductus mesencephali (Sylvii) = for CSF between 3rd and 4th ventricle Brain stem - composition

30. Medulla oblongata Ventral side: pyramis –Fibers of tractus corticospinalis oliva dorsal side: tuberculum gracile + cuneatum

34. Mesencephalon = Mid brain Cranial part of brain stem (2 cm) Ventral side: fossa interpeduncularis (intercruralis) –Exit of n. III crura cerebri –Descending motor systems (tractus pyramidalis) fibrae corticospinales other

35. Dorzal side: lamina quadrigemina = lamina tecti colliculi superiores –vision colliculi inferiores –hearing Exit of n. IV Mesencephalon = Mid brain

36. Mesencephalon = mid brain Internal structure: 3 parts on section tectum mesencephali (mesencephalic tectum) = dorzal thin plate with two pairs of tubers - aqueductus mesencephali Sylvii pedunculus cerebri (brain pedicle) = ventral most of midbrain –tegmentum mesencephali nucleus ruber – motor nucleus of stem substantia nigra – motor nucleus – basal ganglion Ascending and descending tracts –crus cerebri – contains only descending tracts

38. RF

39. Formatio reticularis (reticular formation) RF Fylogenetically oldest part of brain Maintains basic stereotypes (walk, sleep) Influences wake, tiredness and motivation Morphologically ill defined Centrall and dorsally in brain stem, especially in the pons Ascending activation systém → talamus, hypotalamus, cortex Descending inhibitory systém → cerebellum, sensory nerves

40. RF function Seat of reflexes – nutrition – self defense respiratory pneumotactic center vazomotor center center for heart beat rate regulation center for vomiting Pain Body temperature maintenance

41. Cerebellum

42. Cerebellum = small brain vermis (worm) – midline non paired hemispheria (cerebellar hemispheres) – paired cortex x corpus medullare 3 lobes –lobus anterior –lobus posterior –lobus flocculonodularis 4 nuclei cerebelli (small brain nuclei) –nucleus dentatus –nucleus emboliformis –nucleus globosus –nucleus fastigii

43. Cerebellum – posterior view VERMIS

45. Cerebellum – three pedicles pedunculus cerebellaris inferior = corpus restiforme + juxtarestiforme pedunculus cerebellaris medius = brachium pontis pedunculus cerebellaris superior = brachium conjunctivum

46. Cerebellum – ventral view P.C.MEDIUS P.C.SUPERIOR P.C.INFERIOR

47. Diencephalon thalamus metathalamus subthalamus hypothalalmus epithalamus thalamus opticus

48. Thalamus (thalamus dorsalis) „brain secretary“  all except for smell Nuclei parcellated according to position or connection –nuclei anteriores, dorsales, intralaminares, mediani, mediales, posteriores, ventrales, reticularis –specific ncl. ventralis posterolateralis, posteromedialis (VPL, VPM) – hmat, bolest, proprioception ncl. ventralis anterior, lateralis (VA, VL) - motoric –Non specific nuclei - (? function) –Association nuclei

49. Parcellation of thalamic nuclei according to position nuclei anteriores, dorsales, intralaminares, mediani, mediales, posteriores, ventrales, reticularis

50. Metathalamus Lateral geniculate body (corpus geniculatum laterale) – vision center Medial geniculate body (corpus geniculatum mediale) – hearing center

51. Subthalamus zona incerta = unsure region) –Function similar to ncll. reticulares thalami –Making difference of other impulses that regularly enter into talamus nucleus subthalamicus = corpus Luysi –Connected with basal ganglia

52. Hypothalamus Highest autonomic center nuclei x transversal and longitudinal zones Crossing of optic nerve (chiasma opticum) hypophysis Mammillary bodies (corpora mamillaria)

53. Hypothalamus

54. Hypothalamus – fyziology Hormones (blood), nerves, CSF  HYPOTHALAMUS  Endocrine + autonomic system   HOMEOSTASIS emotions (= LIMBIC SYSTEM)

55. Telencephalon = Cerebrum Pallium (pars pallialis; pallium)  cerebrum (= hemispheres) Basal part (pars basilaris)  nuclei basales = bazal ganglias Septal part (pars septalis)  septum

56. Pallium Paired hemispheres (hemishperia) 5 lobes (lobi) –frontal (lobus frontalis) –parietal (lobus parietalis) –occipital (lobus occipitalis) –temporal (lobus temporalis) –insular (lobus insularis) = inzula gyr) x sulci – basic description unit

57. Cortical parcellation (Areae Brodmanni) primary – for one modality association –secondary –terciary example: –area 4 – primary motoric –area 17 – primary visual –area 18,19 – association visual

58. bazal ganglia; nuclei basales Striated body (corpus striatum) –Caudate nucleus (nucleus caudatus) –putamen globus pallidus substantia nigra – in mid brain ncl. subthalamicus – in diencephalon Basic function: motor patterns formation

60. Limbic system „visceral brain“ Around brain stem (= “collar“) emotions, memory, smell Connected with emotional reactions, sexual behavior and offspring care, social behavior, memory and regulation of many autonomic function Cortical and subcortical parts hippocampus corpus amygdaloideum = amygdala other