Nervous System Workshop 1 BIOS1158 2024 PDF

BIOS1158 Structure, Function, and Disease B Semester 2 – 2024 Nervous System I Basic Structures Workshop Developed by Dr Jin Huang email: [email protected] Nervous System 1: Basic Structures Workshop Jigsaw red Understanding the location and...

BIOS1158 Structure, Function, and Disease B Semester 2 – 2024 Nervous System I Basic Structures Workshop Developed by Dr Jin Huang email: [email protected] Nervous System 1: Basic Structures Workshop Jigsaw red Understanding the location and naming of major components of the peripheral nervous system (PNS). 1. On a model of a spinal cord segment, identify the structures in the table, list their function/s and label the diagram below: Structure Function/s a) Dorsal root b) Dorsal root ganglion c) Dorsal horn of grey matter d) Ventral horn of grey matter e) Intermediate zone of grey matter (inter-neurons) f) Ventral roots g) Spinal cord white matter h) Spinal nerves (mixed: sensory and motor fibres are together) i) Dorsal primary ramus (a branch of spinal nerve) j) Ventral primary ramus (a branch of spinal nerve) Nervous System 1: Basic Structures Workshop Jigsaw red Postmortem diffusion MRI of the human spinal cord. Identify as many structures as you can. https://www.sciencedirect.com/science/article/pii/S2213158218300962 Nervous System 1: Basic Structures Workshop Jigsaw red 2. Using the anterior spinal cord model examine the cervical region and identify spinal nerves C1-C8. Note: in the cervical region, there are 8 spinal nerves, but only 7 vertebrae. https://anatomy.elpaso.ttuhsc.edu/modules/spinal_cord_module/spinalcord_04.html Nervous System 1: Basic Structures Workshop Jigsaw red 3. Identify on a vertebral column, the intervertebral foramina (openings) through which C1-C8 spinal nerves travel. Lumbar spine Intervertebral http://drugline.org/medic/term/c4-cervical-vertebra/ foramina https://www.studyblue.com/notes/note/n/superficial-back-/deck/1825926 https://www.pinterest.com.au/pin/109353097180992927/ https://radiopaedia.org/articles/spinal-fractures 4. On the spinal cord model, note the network of nerves (plexus) that carry sensory and motor information for the upper limbs / body. Thus, this plexus innervates the upper body. a) What is the name of this plexus? b) What does this word mean? c) By examining the model, determine which spinal segments form this plexus. Nervous System 1: Basic Structures Workshop Jigsaw red Resources Roots can be sensory or motor in nature:  Dorsal roots: formed by sensory fibres / axons  Dorsal root ganglion: houses cell bodies of sensory neurons  Ventral roots: formed by motor fibres / axons Grey matter: formed by cell bodies of neurons, interneurons, glia cells  Dorsal horn: contains sensory information for fine touch, pressure, proprioception, pain, temperature and coarse touch  Intermediate zone of grey matter (interneurons): relay information, communication between neurons  Ventral horn: cell bodies of motor neurons White matter: formed by columns (nerve fibres / axons  pathways / tracs  columns  white matter), carries electrical signals / actions potentials Nerves: carry sensory and motor information Ramus: is a branch of a nerve, rami: plural of ramus, primary ramus means first branch  Dorsal ramus: innervates the back muscles and skin  Ventral ramus: innervates trunk, upper and lower limbs Dorsal ramus Ventral ramus Figure 12.31, Marieb and Hoehn (2007) Nervous System 1: Basic Structures Workshop Jigsaw red Resources Brachial plexus: formed by C5-T1 spinal roots, innervates upper body. Brachial means arm. https://www.cincinnatichildrens.org/health/b/brachial-plexus http://www.medicalook.com/human_anatomy/organs/Brachial_nerve_plexus.html Nervous System 1: Basic Structures Workshop Jigsaw yellow 5. With the help of the dermatome diagram below, outline on yourself and a fellow student the skin areas innervated by C8 and T12 spinal segments. a) Use the anterior spinal cord model to locate C8 and T12 segments of the spinal cord. b) Use the anterior spinal cord and spinal segment models to trace the path taken by cutaneous (skin) sensation from the dermatome to the spinal cord for each example. c) Which sensory modalities (types of sensation) will follow this path? Figure 3.10. Cutaneous distribution of (right) spinal nerves (dermatomes) and named peripheral nerves (left). Crossman and Neary (2010). Nervous System 1: Basic Structures Workshop Jigsaw yellow Understand the location of the major components of the central nervous system (CNS) 6. On the models of the brain, brainstem and the radiographs (below), identify: a) Cerebrum: left and right hemispheres 1. Frontal lobe 2. Temporal lobe 3. Parietal lobe 4. Occipital lobe 5. Central sulcus 6. Lateral fissure 7. Parieto-occipital fissure 8. Cerebellum 9. Brainstem: connects to cerebellum dorsally via cerebellar peduncles I. Midbrain (connects to the diencephalon superiorly) II. Pons III. Medulla (connects to the spinal cord inferiorly) b) Spinal cord Nervous System 1: Basic Structures Workshop Jigsaw yellow A normal sagittal FLAIR MRI scan. Identify as many structures as you can. http://ar.utmb.edu/webpath/radiol/radnorm/mrifs02.htm Nervous System 1: Basic Structures Workshop Jigsaw yellow A lateral view of the skull (Fig. 1.3, Anatomy for Diagnostic Imaging. Ryan, McNicholas and Eustace.). 7. Identify the bones in ( ) which lie close to each of the following: a) frontal lobe (frontal bone) b) temporal lobe (temporal bone) c) cerebellum (occipital bone) d) brainstem (occipital bone) e) spinal cord (emerges from C1 vertebra) Nervous System 1: Basic Structures Workshop Jigsaw yellow https://www.shutterstock.com/search/skull+side+view http://what-when-how.com/neuroscience/the-spinal-cord-organization-of-the-central-nervous-system-part-1/ Nervous System 1: Basic Structures Workshop Resources  Nervous System 1: Basic Structures Workshop Resources * * * * * * * https://www.pinterest.com.au/pin/412783122090989364/ * https://www.pinterest.com.au/pin/570549846515454896/ Nervous System 1: Basic Structures Workshop Resources a) Frontal lobe (red/pink) Frontal bone b) Temporal lobe (yellow) Temporal bone c) Parietal lobe (purple) Parietal bone d) Occipital lobe (green) Occipital bone e) Cerebellum (brown) Occipital bone (below tentorium cerebelli) f) Brainstem (light brown) Occipital bone (adjacent to clivus) A lateral view of the skull (Fig. 1.3, Anatomy for Diagnostic Imaging. Ryan, McNicholas and Eustace.) Nervous System 1: Basic Structures Workshop Resources https://courses.lumenlearning.com/boundless-ap/chapter/the-skull/ Nervous System 1: Basic Structures Workshop Jigsaw green 8. Most cerebrospinal fluid (CSF) is produced by choroid plexuses inside all ventricles. The remainder is produced by ependymal cells which line all the ventricles. Using models, find the four ventricles and the cerebral (mesencephalic) aqueduct. Label the diagram below. 9. Imagine you are a CSF droplet. On one of the diagrams above, draw your path from the right lateral ventricle to the subarachnoid space (a fluid-filled space surrounding CNS). a) Through which structure does CSF enter the venous drainage system? Nervous System 1: Basic Structures Workshop Jigsaw green T1-weighted MRI of (a): a healthy subject and (b) a normal pressure hydrocephalus subject. Identify as many structures as you can. https://www.sciencedirect.com/science/article/pii/S2213158219302219 b) What happens if there was a blockage in the flow of CSF through the right interventricular foramen? Nervous System 1: Basic Structures Workshop Jigsaw green c) What is name given to the clinical procedure for removal of CSF? d) Why is this carried out? https://ssl.adam.com/content.aspx?productId=10&pid=10&gid=000303&site=morehead2.adam.com&login=MORE6662 http://www.ajnr.org/content/38/7/1276 Nervous System 1: Basic Structures Workshop Resources * https://healthjade.net/cerebrospinal-fluid/ Nervous System 1: Basic Structures Workshop Resources * * * * http://www.aboutcancer.com/brain_anatomy_net_6.gif Internal capsule is a white matter structure composed of ascending and descending fibre tracts. These tracts connect the cerebral hemispheres with subcortical structures, the brainstem, and the spinal cord. The various portions of the internal capsule mostly receive their vascular supply from perforating arteries that arise from the anterior cerebral artery, middle cerebral artery, anterior choroidal artery, and the internal carotid artery. These perforating arteries are prone to lipohyalinosis leading to ischemic damage of areas of the internal capsule resulting in clinically significant motor and sensory deficits. FYI only: Lipohyalinosis (you are not expected to know this term): Degenerative changes in small blood vessels, marked by the accumulation of a glassy- or waxy-appearing lipid within the vessel wall. This type of vascular degeneration occurs in hypertension and atherosclerosis, and predisposes patients to small infarcts, esp. in penetrating arteries of the brain. https://www.ncbi.nlm.nih.gov/books/NBK542181/ https://medical-dictionary.thefreedictionary.com/lipohyalinosis Nervous System 1: Basic Structures Workshop Jigsaw blue 10. Examine a horizontal brain slice and identify the grey and white matter. a) Identify the cerebral cortex and the deep white matter entering and leaving it. b) Identify the thalamus. It is the largest structure in the diencephalon. It sorts most information entering the cerebral cortex. c) Identify basal nuclei which lie deep within the cerebrum as islands of grey matter. d) The large boomerang-shaped band of white matter is the internal capsule that carries most of the information entering and leaving the cerebral cortex. It receives blood supply from anterior cerebral artery (ACA), middle cerebral artery (MCA), anterior choroidal artery and internal carotid artery. Note: we will cover blood supply in later lectures. Internal capsule can be a site of vascular damage such as stroke. e) Stroke affects the arteries leading to and within the. There is a rapid loss of brain function due to a disturbance in the supply of blood to the brain. f) Why is the internal capsule a particularly dangerous region to have a stroke? Nervous System 1: Basic Structures Workshop Jigsaw blue g) On the MRI below, identify structures labeled as 1-8 and note their corresponding structures on the horizontal brain slice you just viewed. 1 5 2 6 3 7 4 8  Nervous System 1: Basic Structures Workshop Resources http://neurovascularmedicine.com/basalgangliastrokes.php 1. Insular cortex 2. Septum pellucidum 3. Corpus callosum 4. Caudate nucleus (head) 5. Internal capsule 6. Putamen 7. Thalamus 8. Fornix: connects the hippocampus to the mammillary bodies