BI2432 Fundamental Neuroscience Lecture 1 PDF

BI2432 Fundamental Neuroscience Dr Jittima Muensoongnoen  Human Neuroanatomy Functional anatomy of the central and peripheral nervous systems Neuroanatomy Practicals: Dissection of the human brain to allow understanding of its...

BI2432 Fundamental Neuroscience Dr Jittima Muensoongnoen  Human Neuroanatomy Functional anatomy of the central and peripheral nervous systems Neuroanatomy Practicals: Dissection of the human brain to allow understanding of its 3D structure and pathways. 1st session –Introduction to the nervous system (station based, prosections) (22nd Oct) 2nd and 3rd sessions – brain dissection (24th Oct and 31st Oct) Formative spotter – scheduled in the session on 22nd Nov Neuroanatomy and Neuropharmacology ICA – 23rd January  HUMAN TISSUE AUTHORITY (HTA) Before the start of the practical on 22th Oct – Refer to ‘HTA and Rules and Regulations’ for the use of Human Tissue that you were given in Year 1. The use of human tissue is tightly regulated by the UK government: THE HUMAN TISSUE AUTHORITY (HTA) RULES MUST BE ADHERED TO ALL TIMES Cardiff is one of a few Neuroscience courses in the UK that learn neuroanatomy by dissecting human tissue. The brains that you will be dissecting belonged to local people and must be treated with the utmost RESPECT at all times  Before attending the practical An email will be sent to you – please read and follow the instruction carefully Watch the brain knife test video before coming to the practical 3. During the practical 3, a member of staff will assess you in your use of instruments. You will demonstrate you can use a brain knife safely and when they are satisfied you are competent, a form will be signed.  Rule and regulation in a practical 1. Mobile phones MUST be switched off and put in your coat pocket or bag and remain in the changing area. Any student with a phone (on or off) in the main practical area will be flagged and reported for serious professionalism issue. 2. Follow the dress code: Please wear long trousers/skirts. No crop tops, ripped jeans, hats or caps (other than those worn because of religious dictates). Wear closed shoes. Anyone dressed inappropriately will not be permitted entry. It is a legal requirement to comply with these regulations. Any issues will be reported immediately as a professionalism concern. In addition, please ensure that you: Yes i. arrive early before the time indicated in your timetable ii. have your ID ready to be checked at the front door iii. leave your mobile phone (switched off) in your coat/bag in the changing area iv. bring your fabric lab coat and goggles Yes Introduction to Fundamental Neuroanatomy  Learning outcomes By the end of the session (and recommended reading) you should be able to: Describe important anatomical terminology and be able to use it appropriately. Explain the divisions of the nervous system, their components as well as their function. Identify the main regions of the brain. Identify the lobes and main cortical areas (primary motor, primary somatosensory, primary auditory and primary visual areas). Identify the components of the ventricular system and describe their location. Describe the production of the CSF and its flow. Identify and describe the arteries supplying the brain which include the internal carotid artery, vertebral artery and their branches. Describe the arterial Circle of Willis and its significance. Describe the 3 layers of the cranial meninges. Name and describe major dural partitions (flax cerebri and tentorial cerebelli) Name and describe major dural venous sinuses and their function. Pictures of the structures (Online version available through the library) Same book but different editions Main books for the introduction lecture Useful Videos (by Dr Alan Watson) on Learning Central 1) External features of the brain 2) Internal features of the brain 3) Cranial nerves 4) Cells of the nervous system  Terminology superior super (rostral) ior Posterior (medic) (dorsal) Anterior (medic) (ventral) inferior (caudal) https://brain.oit.duke.edu/lab01/lab01.html Dissection planes Coronal plane Sagittal plane Horizontal plane  CNS Nuclei and Tracts Nucleus (gray matter): nucleus tract a nucleus is a cluster of cell bodies (and Cell body their dendrites) in CNS where synapses are made and information is processed Cell Cell body body Cell Cell body Tracts (white matter)- bundles of myelinated body axons form tracts connecting nuclei Cell body Cell nucleus body Spinal cord - transverse section Afferent – going towards the central nervous system = sensory neurones Efferent – leaving the central nervous system = motor neurones Somatic: relating to the body (soma = body) Visceral: relating to the viscera (viscera = organs) Functional components of nerves General somatic afferent (GSA) = Carry sensory information to the CNS from muscles and skin General somatic efferent (GSE) = Carry motor information from the CNS to skeletal muscles General visceral afferent (GVA) = Carry sensory information to the CNS from organs and blood vessels General visceral efferent (GVE) = Carry motor information from the CNS to smooth muscle and glands (parasympathetic innervation) Cranial nerves - Special senses  Functional components Special somatic afferent (SSA) = vision, hearing & balance Special visceral afferent (SVA) = smell, taste Special visceral efferent (SVE)= branchial arch striated muscles The Central (CNS) and Peripheral Nervous Systems (PNS) Axons  The Nervous System Central nervous system - Brain (cerebral hemisphere, diencephalon, cerebellum and brainstem) - spinal cord Peripheral nervous system 1) somatic nervous system: peripheral nerves (sensory and motor) - spinal nerves and cranial nerves - voluntary 2) Autonomic nervous system – sympathetic and parasympathetic = visceral - involuntary (cardiac muscle, smooth muscle and glands) dorsal root ganglion Ganglion - a collection of cell bodies of neurones found in spinal nerve the peripheral nervous system e.g. dorsal root ganglion Remember: Nucleus (CNS) vs Ganglion (PNS)  Early development of the brain Neural tube Five secondary brain vesicles: 1. Telencephalon - cerebral cortex and basal ganglia 2. Diencephalon - optic stalk, optic cup, thalamus, hypothalamus, pituitary gland, pineal gland. 3. Mesencephalon - midbrain 4. Metencephalon - pons & cerebellum 5. Myelencephalon - medulla oblongata Midbrain + pons + medulla = brainstem  The main regions of the brain Which plane? cerebral hemisphere Basal ganglia diencephalon midbrain caudate nucleus cerebellum putamen pons medulla globus pallidus Brainstem: midbrain, pons and medulla. Which plane? Coronal You will learn more - ‘Brainstem’ lecture Which plane? Sagittal section frontal parietal Corpus callosum occipital diencephalon posterior cerebellum midbrain anterior pons Temporal medulla Spinal cord – transverse section Cerebral cortex White Grey matter matter Myelin sheath is stained - dark cortex cerebellum The cortex is a six layered sheet of grey matter. Folding this sheet packs more of the grey matter sheet into the volume available  Cerebral cortex gyrus = ridge (plural: gyri) Sulci sulcus = groove (pleural: sulci) Gyri sulcus vs fissure Coronal Lateral view  Lobes Lateral sulcus (Sylvian fissure) Longitudinal Central sulcus fissure Parieto- Parietal occipital Frontal sulcus Cerebral Cerebral hemisphere hemisphere l ita cip Temporal Oc Lateral sulcus Superior view Lateral view Sagittal section Calcarine sulcus Parieto-occipital sulcus  Cortical areas Central sulcus Precentral gyrus – primary motor area al gyr centr l gyr entra Postcentral gyrus – primary us t Pos somesthetic us c Pre (somatosensory) area  Cortical areas Central sulcus Precentral gyrus – primary motor area al gyr centr l gyr entra us Postcentral gyrus – primary somesthetic area t Pos us c Pre  Cortical areas Precentral gyrus – primary motor area al gyr centr l gyr entra us Postcentral gyrus – primary somesthetic area t Pos us c Pre Lateral sulcus  Cortical areas Precentral gyrus – primary motor area al gyr centr l gyr entra us Postcentral gyrus – primary somesthetic area t Pos us c Pre Primary visual Primary area auditory area Cortical areas Calcarine sulcus Cortical areas Calcarine sulcus Primary visual area Function of the cerebral cortex Phineas Gage (1823-1860) Left frontal lobe injury Personality & behaviour Cortical areas In the 19th century, Korbinian Brodmann (German anatomist) divided the cortex into a number of regions based on fine structures and neuronal components of its six layers. These later turned out to correspond quite well to functional regions of the cortex, so his numerical system is still used today. Some Brodmann areas: 4 primary motor cortex 6 pre-motor/supplementary motor cortex 9, 10, 11, 12 prefrontal cortex 3, 1, 2 primary somatosensory area 17 primary visual cortex 18, 19 visual association cortex 41, 42 primary auditory cortex 22 Wernicke’s area (sensory speech area) 44, 45 Broca’s area (motor speech area) You will learn more - ‘Cortex’ lecture.  Ventricular System These are filled with a cerebrospinal fluid (CSF); basically a saline solution derived from blood plasma, but lacking proteins or cells. 3D - https://sketchfab.com/3d-models/ventricles-a5c44ec4384a423f8df9c17d3dab43fc  Interventricular foramen (of Monro) (Frontal, parietal, Ventricles; spaces within the brain occipital and temporal lobes} filled with cerebrospinal fluid (secretes (CSF) CSF} (diencephalon (thalamus/ hypothalamus ) (midbrai n} (pons & medulla} Choroid plexus produces CSF Functions….. 1) The brain floats in CSF which supports its weight, preventing compression of its blood supply. It buffers the brain against the effects of blows to the head. 2) It may wash out metabolic waste products. Ventricles Frontal Parietal Corpus callosum Occipital Septum pellucidum Cerebral aqueduct (midbrain) Lateral ventricle Interventricular foramen 4th ventricle 3rd ventricle Temporal  Blood Supply: Arteries and Veins Arteries – carry blood away from the heart to parts of the body (mostly move oxygenated blood to organs) Veins – carry blood towards the heart from parts of the body (mostly drain the deoxygenated blood from the organ (via dural venous sinuses in the brain)  Two large arteries supply the brain on each side Brain arterial circulation 1) Internal carotid arteries* ventral view 2) Vertebral arteries** anterior cerebral middle cerebral internal carotid* posterior cerebral basilar vertebral arteries** Vertebrobasilar system  Brain arterial circulation You will learn about this later anterior anterior cerebral communicating artery middle cerebral internal carotid* internal posterior Carotid Circle of Willis communicating Arteries * artery posterior cerebral pontine superior branches cerebellar basilar basilar artery anterior inferior cerebellar vertebral arteries** posterior inferior cerebellar vertebral arteries**  Meninges 3 layers of membranes surround the brain Dura mater tough parchment like double bone layer – meningeal (inner) and periosteal (outer) Arachnoid mater very thin with subarachnoid space beneath containing brain Cerebrospinal Fluid. Pia mater thin and adherent to brain surface Gray’s Rohan Color Atlas of Anatomy scalp skull dura arachnoid subarachnoid Contains CSF space cortex pia  Where the 2 layers of the cranial dura Dura mater separate will form: Outer periosteal layer Meninges – Dura mater Dural venous Inner meningeal Dural venous sinus sinuses layer Dural partitions Dural partition Cortex  Dural partitions 1) The falx cerebri lies on the midline, between the two tentorial falx cerebri cerebral hemispheres of the notch (sickle) forebrain 2) The tentorium cerebelli lies between the occipital lobe of the cortex and the cerebellum tentorium cerebelli Gray’s  Dural venous sinuses Dural venous sinuses are inferior sagittal sinus superior sagittal sinus spaces within (the 2 layers of) the dura that drain blood falx cerebri from veins within the brain great cerebral vein straight sinus CONFLUENCE OF SINUSES transverse sinus tentorium cerebelli cavernous sigmoid sinus sinus Barr Dural partitions and dural sinuses jugular foramen sigmoid sinus tentorium inferior sagittal sinus falx (cut edge) superior sagittal sinus transverse sinus Dural venous sinuses superior and inferior sagittal sinuses sigmoid sinus (drains through jugular - foramen) straight sinus transverse sinus Gray’s Anatomy for medical students Sigmoid sinus continuous inferior with the internal jugular vein heart The CSF that fills the subarachnoid space drains via the arachnoid granulations into the venous blood within the superior sagittal sinus. Superior sagittal sinus Subarachnoid space contains CSF Arachnoid granulations Questions? www.pinterest.com