Notes in Neuroscience 2024/2025 PDF

Notes in Neuroscience Dr / HAMADA ZEHRY, MD Lecturer of Neurology , Horus University  Headache Hemiplegia Flipped learning Ataxia Hyper or hypokinetic MD  ‫الخطة الدراسية للعام الحالي‬ Quiz (2) 7 marks Mid-term (electronic) with routine lectu...

Notes in Neuroscience Dr / HAMADA ZEHRY, MD Lecturer of Neurology , Horus University  Headache Hemiplegia Flipped learning Ataxia Hyper or hypokinetic MD  ‫الخطة الدراسية للعام الحالي‬ Quiz (2) 7 marks Mid-term (electronic) with routine lectures 10 marks Activities (2 e.g. scientific days , researchs ,…. ) 3 marks Final exam (MCQ + flipped learning + short essay ) 80 marks Total = 100 marks N:B ) no retake for any exams or quizzes  ILOs Definition of neuroscience Parts of neuroscience Neuropathology notes Neurochemistry notes Neuroanatomy notes Definition of neurology  Neuroscience  A human brain contains roughly 86 billion nerve cells, or neurons.  The brain is literally the “nerve center” of your body — it contains billions of neurons that transmit information from the body and the outside world, and then programs our responses — conscious and unconscious movements, thoughts, emotions, and memories.  The term "neuroscience" refers to the scientific study of the nervous system. The word is derived from a combination of the words "neuron" meaning "nerve" and "science".  Neuroscience concerns all scientific aspects of the nervous system including molecular, cellular, functional, and structural elements as well as the evolutionary, medical and computational aspects. Some examples of the principal areas studied are: (Neurophysiology, neurochemistry and neuropathology. ❖ Neuroanatomy ❖ Neuropharmacology and psychology ❖ Brain imaging in diagnosis of disease ❖ Neurology and psychiatry). Histologically CNS composed of ( neuron and supporting neuroglia cells ) Neuron divided to sensory, motor and interneurons  The major types of neurons in the nervous system: o Excitatory glutamatergic pyramidal neurons—80% of neocortical neurons, long range o Inhibitory gamma aminobutyric acid-ergic (GABAergic) interneurons— 20% of neocortical neurons, mostly local o Neuromodulatory neurons—neurons expressing acetylcholine, dopamine, serotonin, norepinephrine, epinephrine, histamine, and neuropeptides such as orexin/ hypocretin, somatostatin that often also corelease the classical neurotransmitters glutamate or GABA.  The major types of glia in the nervous system: o Astrocytes—establish the blood–brain barrier, flux ions, repair and form scars in injury o Oligodendroglia and Schwann cells—form myelin in brain/spinal cord and periphery o Ependymal cells—neuroepithelial cells lining the ventricles, choroid, spinal cord central canal, form cerebrospinal fluid, nonrenewing stem cell pool producing neurons in adult central nervous system (CNS) injury o Microglia—resident inflammatory phagocytes in infection, degeneration, demyelination  The major subcellular compartments of the neuron affected in disease: o Soma—site of pathological inclusions in neurodegenerative diseases o Dendrites—loss of dendritic spines in autism o Axon—susceptibility to shearing in traumatic brain injury, loss in Wallerian degeneration o Nodes of Ranvier—susceptibility to dysfunction in channelopathies o Myelin—loss in demyelinating diseases Neuroanatomy notes Neuroanatomy notes  I-Intracranial part: 1-Cerebrum. 2-Brain Stem. 3-Cerebellum.  Formed of: Two cerebral hemispheres. Connected to: -Each other by the corpus callosum. -The brain stem by the cerebral peduncles. Composed of: The a-Outer gray matter of nerve cells (cerebral cortex). Cerebrum b-Inner white matter of nerve Fibers. c-Basal nuclei of nerve cells (basal ganglia, thalamus etc) Divided to: Four lobes (frontal, parietal, temporal & occipital).  Formed of: 1-Midbrain. 2-Pons. 3-Medulla. Connected to: -Cerebral hemispheres by cerebral peduncles. -cerebellum by cerebellar peduncles. The Contains: -Groups of nerve cells (cranial nerve Brain nuclei) Cr 3 & 4 in Midbrain. Stem Cr 5, 6, 7 & 8 in pons. Cr 9, 10, 11 & 12 in Medulla. -Several ascending and descending fibers.  Lies: Behind the brain stem. Formed of: -Mid line Vermis. The -Two lateral Cerebellar Hemispheres. Composed of: cerebellum -Grey matter (cerebellar cortex & nuclei). -White matter (entering & leaving fibers). II-Spinal part: 1-spinal cord. 2-Cauda equina.  Lies in the spinal canal. Ends at the lower border of L1 The vertebra. Its lower most 3 segments (S3,4,5) = Spinal the Conus Medullaris. The above 4 segments (L4,5 & S1,2) = the Epiconis. Cord Formed of H shaped gray matter (cells) surrounded by white matter (tracts). The Cauda Equina The collection of lumbosacral roots which fills the lower part of the spinal canal below the lower border of L1 vertebra.  P.N.S. I-Neural part. II-Muscular part.  1-Roots: The Cervical, dorsal, lumbar & sacral. 2-Plexuses: Brachial & lumbosacral. Neural 3-Peripheral nerves: Ulnar, median, radial, femoral part: etc. II-Muscular part: 1-Myoneural junction: Motor end plate. 2-Muscles: Muscle membrane. Muscle fibers. Voluntary motor pathway I-Upper Motor Neurone (U.M.N.). II-Lower Motor Neurone (L.M.N.). U.M.N. Originates: Mainly in large pyramidal cells of the motor area. Descend: In the corona radiata to the internal capsule, then to the midbrain, pons & medulla. Decussates: To descend in white matter of opposite side of the spinal cord. Terminates: at - A.H.C.S of the spinal cord (corticospinal tract). -Motor nuclei of Cr nerves (Corticobulbar tract). L.M.N. Originates: in -A.H.C.s of the spinal cord. -Motor nuclei of Cr nerves in the brain stem. Exits: from -The spinal cord as the anterior roots. -The brain stem as the Cranial nerves. Continue: as -Peripheral nerves. -Cranial nerves. Terminates: At the voluntary muscles.  U.M.N. & L.M.N. Lesions U.M.N. L.M.N. Muscle state Late diffuse disuse wasting Early marked selective wasting Muscle tone Hypertonia (spasticity) Hypotonia (flaccidity) at below the level of lesion the level of lesion Muscle power Weakness below the level of Weakness at the level of lesion leseion Deep reflexes Exaggerated below the level Diminished at the level of of lesion lesion Clonus May be present Absent Superf. reflexes Lost below the level of Lost at level of lesion lesion Planter reflex Extensor planter response No or flexor planter response [email protected] +201091949392 Any Question?