Medical Terminology: The Nervous System (2022-2023) PDF

MEDICAL TERMINOLOGY T H E N E RVO U S S YS T E M D R / M A RWA Y O U S S E F LECTURER OF PHARMACOLOGY&TOXICOLOGY  NERVOUS SYSTEM The nervous system coordinates the body’s involuntary and voluntary actions. It works in conjunction with the endocrine system to maintain hom...

MEDICAL TERMINOLOGY T H E N E RVO U S S YS T E M D R / M A RWA Y O U S S E F LECTURER OF PHARMACOLOGY&TOXICOLOGY  NERVOUS SYSTEM The nervous system coordinates the body’s involuntary and voluntary actions. It works in conjunction with the endocrine system to maintain homeostasis (Stay the same), a term that means “a state of equilibrium.” Enable the body to respond and adapt to changes. The nervous system has two main divisions: The central nervous system (CNS) The peripheral nervous system (PNS). NERVOUS SYSTEM NERVOUS SYSTEM NERVOUS SYSTEM MENINGES  NERVOUS SYSTEM Nerve tissue is composed of fundamental units called neurons (nerve cells). The three main parts of a neuron cell are its cell body, dendrites, and axon. The cell body contains the nucleus and receives nerve impulses (action potentials) from other cells through the dendrites. The cell body passes these messages to the axon, which conducts nerve impulses away from the cell body. Axons are covered by myelin, a white fatty material that provides protection and insulation. NERVOUS SYSTEM The gaps that Connect neurons or neurons and muscles are called synapse. Synaptic connections can occur between two nerve cells. The stimulus between the two cells is usually a chemical called a neurotransmitter. Groups of neuron cell bodies within the PNS are called ganglia (ganglion, singular). Groups of neuron cell bodies within the CNS are called nuclei (nucleus, singular). Groupings of axons are called nerves, wherever they occur in the body. ROOT WORDS ASSOCIATED WITH NERVOUS SYSTEM Word Part Meaning neur/o nerve, nerve tissue encephal/o brain cephal/o head cerebell/o cerebellum cerebr/o cerebrum; also, the brain in general cortic/o outer layer or covering crani/o cranium, skull meningi/o membrane ment/o referring to the mind psych/o mind schiz/o to split SUFFIXES DESCRIBING CONDITIONS OR DISORDERS OF NERVOUS SYSTEM Word Part Meaning -mania morbid attraction to or impulse toward (madness) -mnesia memory -phasia speech -phobia fear - phrenia mind -lepsy Seizures EXAMPLES Aphasia Loss of speech Amnesia Loss of memory Meningitis Inflammation of the meninges Schizophrenia Mind splitting  DISORDERS RELATED TO THE NERVOUS SYSTEM 1- Trauma Traumatic brain injury (TBI) is sudden damage to the brain caused by a blow or jolt to the head. Common causes include car or motorcycle crashes, falls, sports injuries, and assaults. Trauma Head injuries can produce skull fractures, hemorrhage, swelling, and direct damage to the brain itself. Brain injury can range from mild concussions to severe permanent brain damage.  DISORDERS RELATED TO THE NERVOUS SYSTEM Common types of brain trauma: A. Concussion is an injury to the brain resulting from violent shaking or a hit to the head. A concussion may cause temporary loss of consciousness followed by a short period of amnesia (loss of memory). Dizziness, nausea, and headache are common with a concussion. B. Epidural hematoma occurs when blood collects between the dura mater and the skull, causing pressure on the blood vessels and interrupting blood flow to the brain. This condition is caused by a skull fracture or a hit to the head C. Subdural hematoma is a collection of blood trapped in the subdural space, the area beneath the dura mater. It may result from a hit to the front or back of the head.  DISORDERS RELATED TO THE NERVOUS SYSTEM 2- Vascular Insults A vascular insult is an injury to the blood vessels. A. Stroke: It results from an interruption of oxygen caused by blood vessel blockage or rupture B. Transient ischemic attack: It is a temporary interruption in the blood supply to the brain. This is sometimes called a “mini-stroke,” but can indicate serious problems and be a forewarning of a stroke. C. Cerebral aneurysm: An aneurysm is a localized dilation (widening) of an artery caused by weakness in the vessel wall. Aneurysm from greek word “aneurysma” which means widening. DISORDERS RELATED TO THE NERVOUS SYSTEM 3-Tumors Tumors are lesions (regions in an organ that are damaged) or neoplasms that may cause localized dysfunction, producing an increase in intracranial pressure (ICP). Tumors may be benign or malignant. Two examples of tumors occurring in the nervous system include  Astrocytoma is a tumor derived from a star-shaped type of neuroglia called an astrocyte.  Meningioma is a tumor derived from the meninges surrounding the brain and spinal cord. DISORDERS RELATED TO THE NERVOUS SYSTEM 4- Systemic Degenerative Diseases These are progressive deterioration of the nervous tissue that affects body. Examples of systemic degenerative diseases include Multiple sclerosis (MS), is a progressive degenerative disease with symptoms caused by demyelination, a patchy loss of the myelin sheath. Parkinson’s disease (PD), usually develops after age 60 and occurs with the loss of the neurotransmitter dopamine (DA). This can affect posture, balance, speech, and other activities of daily living. Alzheimer’s disease (AD) is a atrophy of the cerebral cortex, producing a progressive loss of intellectual function. (Amnesia) DISORDERS RELATED TO THE NERVOUS SYSTEM 5- Seizures A seizure occurs when there is an abnormal, uncontrolled burst of electrical activity in the brain. Seizures may result from trauma, tumors, fevers, medications, or other causes. Epilepsy is a chronic disorder characterized by recurrent seizures that result from the excessive discharge of neurons in the brain.  DISORDERS RELATED TO THE NERVOUS SYSTEM 6- Behavioral Disorders Some behavioral disorders are related to the nervous system. They may be caused by physical changes, substance abuse, medications, or any combination thereof. Anxiety disorders are characterized by feelings of uneasiness, sometimes associated with the anticipation of danger. Depression, which is characterized by loss of interest or pleasure in activities Schizophrenia, which is characterized by abnormal thoughts, hallucinations, delusions, and withdrawal. SPECIALITY Neurologists are medical specialists trained in the diagnosis and treatment of neuromuscular disorders. Neurosurgeons are physicians specialized in operations on the brain, spinal cord, and peripheral nerves. Psychiatrists are physicians who treat behavioral and mental health disorders.