* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Chapter 45 Central Nervous System BRain
Donald O. Hebb wikipedia , lookup
Neurogenomics wikipedia , lookup
Intracranial pressure wikipedia , lookup
Neuroeconomics wikipedia , lookup
Molecular neuroscience wikipedia , lookup
Premovement neuronal activity wikipedia , lookup
Neuroinformatics wikipedia , lookup
Neurolinguistics wikipedia , lookup
Central pattern generator wikipedia , lookup
Optogenetics wikipedia , lookup
Neurophilosophy wikipedia , lookup
Brain morphometry wikipedia , lookup
Biochemistry of Alzheimer's disease wikipedia , lookup
Clinical neurochemistry wikipedia , lookup
Aging brain wikipedia , lookup
Brain Rules wikipedia , lookup
Development of the nervous system wikipedia , lookup
Neural engineering wikipedia , lookup
Feature detection (nervous system) wikipedia , lookup
Blood–brain barrier wikipedia , lookup
Microneurography wikipedia , lookup
Human brain wikipedia , lookup
Selfish brain theory wikipedia , lookup
Channelrhodopsin wikipedia , lookup
Evoked potential wikipedia , lookup
Neuroregeneration wikipedia , lookup
Cognitive neuroscience wikipedia , lookup
Holonomic brain theory wikipedia , lookup
Neuroplasticity wikipedia , lookup
Stimulus (physiology) wikipedia , lookup
Nervous system network models wikipedia , lookup
Sports-related traumatic brain injury wikipedia , lookup
History of neuroimaging wikipedia , lookup
Neuropsychology wikipedia , lookup
Metastability in the brain wikipedia , lookup
Haemodynamic response wikipedia , lookup
Circumventricular organs wikipedia , lookup
Neuro – A & P, Assessment, Diagnostics Chapter 41 Spring News Grey’s Anatomy Quote • The brain is the human body's most mysterious organ. It learns. It changes. It adapts. It tells us what we see. What we hear. It lets us feel love. I think it holds our soul. But no matter how much research we do, no one can really say how all that delicate gray matter inside our skull works. And when it's hurt, when the human brain is traumatized, well... that's when it gets even more mysterious. Nervous System • What does it do? • How does it do it? ANATOMY Neurons • • • • • • Initiate and transmit impulses High metabolic rate Longevity Typically non-mitotic Variety of shapes and sizes Comprised of a cell body, dendrites and axons Sensory vs. Motor • Sensory Neurons (afferent) – Transmit information to the CNS • Motor Neurons (efferent) – Transmit information away from the CNS Impulse Conduction Reflex Arc – Functional unit that provides the pathways for the nerve impulses – The passage of the impulses is called • Reflex act or Reflex – Process of Reflex Arc • Neural impulses Anatomy Neuroglial Cells – Four types • Capable of mitosis and replacing damaged neurons • Aid in neuronal development • Do not transmit nerve impulses • Protect, nourish and provide support for the neurons Anatomy Action Potentials – Movement of an electrical charge thru an impulse along the axon membrane – Allows for communication with neurons and body cells – Initiated by a stimulus – Propagated by rapidly charged ions thru the cell membrane – Faster in myelinated fibers Anatomy Neurotransmitters • Synaptic Transmission – One way communication that link the neurons by a chemical synapse – Either inhibitory or excitatory – Chemical neurotransmitters • • • • • • Acetylcholine Norepinephrine Dopamine Histamine GABA (gamma aminobutyric acid) Serotonin Factors Effecting Neurotransmission • Distance • Strength of Stimulus – Inhibition – Inadequate transmitter substance – ECF changes • pH • O2 • Medications PHYSIOLOGY Physiology • Central Nervous System (CNS) – Brain – Spinal Cord Brain Parts and Function • • • • • Bone Meninges Cerebrum Brainstem Circle of Willis Brain Table 41-1 General Functions of the Four Regions of the Brain Figure 41–3 Lobes of the cerebrum and functional areas of the cerebral cortex. Table Functions of Lobes of the Cerebrum and Areas of the Cerebral Cortex CSF • Clear and Colorless • From blood plasma – 99% water – Contains protein, sodium, chloride, potassium, bicarbonate and glucose • 80 – 200 mL total volume – Replaced several times per day • Cushion for the brain and spinal column • Provides nourishment and removes waste Circulation and the BBB Circulation • 750 mL of blood per minute • Uses 20% of the total O2 – Needed for the metabolism of glucose – sole source of energy. BBB • Allows lipids, glucose, some amino acids, water, CO2 and O2 • Other substances are prevented from crossing Figure 41–5 Major arteries serving the brain and the Circle of Willis. Spinal Cord • Center for conducting messages to and from the brain and a reflex center • 33 vertebrae – – – – – 7 cervical 12 thoracic 5 lumbar 5 sacral 4 fused which form the coccyx Function Ascending tracts- start in spinal cord and end in the brain • Spinothalamic • Spinocerebellar Descending tracts - start in the brain and end in the spinal cord Physiology • Peripheral Nervous System (PNS) – 12 pairs of Cranial nerves – 31 pairs of Spinal nerves – Autonomic nervous system • Sympathetic system • Parasympathetic system • Cranial Nerve Song Dermatones • Area of skin that is innervated by cutaneous branches of a single spinal nerve • Provide anatomic landmarks to locate neurologic lesions Autonomic Nervous System Regulates involuntary activity (cardiovascular, respiratory, metabolic, body temps etc) • Sympathetic (SNS) • Parasympathetic (PNS) Autonomic Nervous System Area Affected Sympathetic Parasympathetic Pupil Dilates Constricts Bronchi Dilates Constricts Heart Increases Rate Decreases Rate GI Inhibits peristalsis Stimulates sphincter Stimulates peristalsis Inhibits sphincter Adrenal Glands Increases secretion of EN and NE Bladder Relaxes Bladder muscle Constricts sphincter Contracts bladder muscle Relaxes sphincter Neurological Assessment History • Family history/genetic risks • Personal history • Current health problems • Social history Mental Assessment • • • • • Mental status Memory Attention Language/Copying Cognition Cranial Nerve Assessment • Done to establish a baseline for future comparison to rule out deterioration Sensory Function Assessment • Completed on patients with problems affecting spinal cord or spinal nerves: trauma, intervertebral disk disease, infections • Evaluate: pain, temperature touch Figure 41–12 Testing two-point discrimination. Assessment of Motor Function • Muscle strength • Cerebral/brainstem integrity • Pronator Drift Assessment of Cerebellar Function • Coordination • Gait and equilibrium Figure 41–13 Heel-to-shin test. Assessment of Reflex Activity • Deep tendon reflexes • Cutaneous (Superfical) reflexes • Abnormal findings Box 41-1 Abbreviated Neurologic Assessment (Neuro Check) Table 41-5 Glasgow Coma Scale Diagnostic Assessment • Laboratory –CSF • Lumbar Puncture Diagnostic Assessment • Radiographic –Cerebral Angiography –CT –PET –SPECT –Cerebral Blood Flow Evaluation –Brain Scan Diagnostic Assessment • Other –MRI –EEG –EMG –Transcranial Doppler