Anatomy of a neuron Cell Body (soma) Receives information from the soma s extensions (dendrites) Central Nervous System January 7, 2016 Passes on information away from the soma towards extensions (axons) Axon Conducts nerve impulses (AP) away from soma Nervous tissue Neuronal circuitry Nervous tissue is specialized tissue for reacting to stimuli and transmitting impulses. The nervous tissue/system is made up of two main cell types: 1. Neurons excitable cells that transmit electrical signals 2. Support cells (glia) cells that surround and assist neurons Microglia: Specialized macrophages, ~15% Macroglia Oligodendrocytes (coat axons In CNS) (~Schwann cells in PNS) Astrocytes (control external chemical environme (~satellite cells of PNS) Ependymal Cells: Coat cavities (ventricles) Lalo et al. J. Neurosci 26:2673 83. Classification Spinal cord: spinal tracts 13-6 1
Reticular formation Crown 85 Centra Nervous System Anataomy 1/7/2016 Classification CNS: Processing center PNS: 12 pairs of cranial nerves 31 pairs of spinal nerves Sensory (afferent) division carries sensory information from the body to the CNS; Somatosomatic Visceral Nociception Propioceptors Central Nervous System brain: major portion of the central nervous system Cerebrum: Motor (efferent) division Response: Transmits impulses from the CNS to organs involved in the response Striated muscle cells: voluntary Smooth muscle cells: involuntary glands 15-8 Embryology of CNS:Ventricular System MRCPCH : Embryology of CNS by MrcpchTeam www.ezqmeceu.com Embryology of CNS: Ventricular System Anatomical elements of the brain Hindbrain http://drugster.info/img/term/cerebral-ventricle-2808_2.gif 15-12 2
Brainstem and diencephalon: overview Brainstem: Pons and Medulla Oblongata Anatomical elements of the brain:midbrain Anatomical elements of the brain: diencephalon Infundibulum Caudal view 15-15 Rostral view Todd R. Olson. A.D.A.M. Student atlas of anatomy. Anatomical elements: Cerebellum Cerebellum histology Purkinje cells compare information of Intention vs outcome Cortex: input Deep nuclei: output 3
Opistotonus in dinosaurs Posture suggesting of severe spastic distress sal2560x_1512l.jpg https://laelaps.wordpress.com/2007/06/11/opisthotonus-in-dinosaurs/ Cerebrum: Somatosensory perception Sensory cortex Input from general senses Gracile fasciculi Cunerate faciculi Spinothalamic tract Thalamus Postcentral gyrus (association a. for taste and smell) addictivebehaviors.wordpress.com Cerebrum: Motor control Anatomical elements of the brain: cerebrum Motor association area in frontal lobe Motor homunculus Precentral gyrus Brainstem and spinal cord Synapse with lower motor neuron Feedback circuitry for planning and execution of movement Thalamus Muscle contraction Cerebellum comparator coordinator Sulci gyri Basal nuclei: input from all cortex areas except vis and aud Control of highly practiced behaviors repetitive movements 4
Limbic system Cerebrum: Lateralization Cerebrum: language production Malfunctions Area (Left hemisphere) Role Area (Right hemisphere) Wernicke (crossroad between visual, auditory, and somatosensory) Angular gyrus (posterior and superior) Broca Insula Recognition of spoken and written language Reading and writing Motor program for speech Understanding spoken language Attention to objects in environment Domoic acid poisoning Area affected Substantia nigra Basal nuclei Pathology Parkinson s disease Dyskinesias Inhibited movements Exagerated movements (ballismus) Marine Animal Center Fort McArthur s slide Language areas, VII and XII Aphasias Cerebellum Hippocampus ADHD (impulse control problems) No new declarative memories Frontal lobe Irresponsible behavior, profanity Phineas Gage s 1848 accident Architechture of autonomic vs motor Reflexes: Somatic vs autonomic 5
Dual innervation and autonomic tone Fight or flight vs Relaxing over a meal http://human-anatomyphysiology.blogspot.com/2010/03/fight-or-flight-sympathetic-nervous.html 6