Disorders of Neurological Function PDF

DISORDERS OF NEUROLOGICAL FUNCTION PATH 200 Outline: Anatomy of the Nervous System Pain Headache Meningitis Stroke Multiple sclerosis Parkinson’s disease Seizures PATH 200 OBJECTIVES By the end of this lecture the students will be able...

DISORDERS OF NEUROLOGICAL FUNCTION PATH 200 Outline: Anatomy of the Nervous System Pain Headache Meningitis Stroke Multiple sclerosis Parkinson’s disease Seizures PATH 200 OBJECTIVES By the end of this lecture the students will be able to: ⮚ List down the functions of Nervous system ⮚ List down the components of nervous system ⮚ Describe the pathophysiological changes in disorders of neural function PATH 200  Anatomy of The Nervous System ⮚ The nervous system coordinates and organizes the functions of all body systems. ⮚ This intricate network of interlocking receptors and transmitters is a dynamic system that controls and regulates every mental and physical function. It has three main divisions: Central nervous system (CNS)— the brain and spinal cord Peripheral nervous system—the motor and sensory nerves, which carry messages between the CNS and remote parts of the body Autonomic nervous system—actually part of the peripheral nervous system, regulates involuntary functions of the internal organs.  Division of the Nervous System PATH 200  Functions of the Nervous System ▪ Controls skeletal muscle movement ▪ Helps to regulate cardiac and visceral smooth muscle activity ▪ Enables the reception, integration, and perception of sensory information ▪ Provides the substratum necessary for intelligence, anticipation, and judgement ▪ Facilitates adjustment to an ever-changing external environment PATH 200 Neurons  Synapses ⮚ Neurons communicate with one another at junctions called synapses. At a synapse, one neuron sends a message to a target neuron—another cell. ⮚ Most synapses are chemical; these synapses communicate using chemical messengers. Other synapses are electrical; in these synapses, ions flow directly between cells. ⮚ At a chemical synapse, an action potential triggers the presynaptic neuron to release neurotransmitters. These molecules bind to receptors on the postsynaptic cell and make it more or less likely to fire an action potential.  Neurotransmitters The chemical messengers are released from neurons at synapses so that they can communicate with neighboring cells. Acetylcholine (ACh) Biogenic Amines - Dopamine, Norepinephrine, Epinephrine, Serotonin Amino Acids Peptides - endorphins Novel or Miscellaneous PATH 200 Certainly! Here are some scenario-based multiple-choice questions (MCQs) related to different types of pain: ### Question 1 A 35-year-old woman accidentally cuts her finger while chopping vegetables. She describes the pain as sharp and burning. What type of pain is she experiencing? A) Deep Pain B) Visceral Pain C) Cutaneous Pain D) Referred Pain **Answer:** C) Cutaneous Pain ### Question 2 A 50-year-old man visits the doctor complaining of a dull, throbbing pain in his lower back that worsens after physical activity. The pain seems to radiate into his buttocks and thighs. What type of pain is he most likely experiencing? A) Cutaneous Pain B) Deep Pain C) Visceral Pain D) Acute Pain **Answer:** B) Deep Pain ### Question 3 A patient arrives at the emergency room with severe abdominal pain. After examination, the doctor suspects gallstones. The patient describes the pain as diffuse and hard to pinpoint. What type of pain is this? A) Referred Pain B) Acute Pain C) Cutaneous Pain D) Visceral Pain **Answer:** D) Visceral Pain ### Question 4 During a routine check-up, a patient mentions experiencing persistent shoulder pain. Further investigation reveals that the pain is actually due to an underlying heart condition. What type of pain is this an example of? A) Deep Pain B) Referred Pain C) Chronic Pain D) Cutaneous Pain **Answer:** B) Referred Pain ### Question 5 A young athlete suffers a sprained ankle during a basketball game and experiences immediate, intense pain accompanied by sweating and increased heart rate. What type of pain does this scenario describe? A) Chronic Pain B) Visceral Pain C) Acute Pain D) Deep Pain **Answer:** C) Acute Pain ### Question 6 An elderly woman has been living with joint pain for several years, which has led to sleep disturbances and depression. What type of pain is she experiencing? A) Acute Pain B) Chronic Pain C) Referred Pain D) Cutaneous Pain **Answer:** B) Chronic Pain PATH 200 These questions are designed to test understanding of different types of pain through real-life scenarios. Sources  PAIN CLASSIFICATION OF PAIN Cutaneous pain is a sharp, burning pain that has its origin in the skin or subcutaneous tissues. Deep pain is a more diffuse and throbbing pain that originates in structures such as the muscles, bones, and tendons and radiates to the surrounding tissues. Visceral pain is a diffuse and poorly defined pain that results from stretching, distention, or ischemia of tissues in a body organ. Referred pain is pain that originates at a visceral site but is perceived as originating in part of the body wall that is innervated by neurons entering the same segment of the nervous system. Acute pain usually results from tissue damage and is characterized by autonomic nervous system responses. Chronic pain is persistent pain that is accompanied by loss of appetite, sleep disturbances, depression, and other debilitating responses  Pain processing involves four key stages: transduction, transmission, modulation, and perception. Here's a simple explanation of each, with examples: Anatomy of The Pain Pathway ## Transduction **Explanation:** Transduction is the conversion of a noxious stimulus (chemical, mechanical, or thermal) into an electrical signal by nociceptors (pain receptors). **Example:** When you touch a hot surface, the heat is converted into an electrical signal by Transduction: Conversion of a noxious stimulus receptors in your skin. ## Transmission **Explanation:** (chemical, mechanical, or thermal) into electrical energy Transmission is the process where the electrical signal travels from the site of injury to the spinal cord and then to the brain. **Example:** The signal from a burn travels via nerves to the spinal cord's dorsal horn and then to the Transmission: Electrical stimulus is sent to the dorsal hornbrain. ## Modulation **Explanation:** of the spinal cord and synapse at the 2nd order neuron Modulation involves either amplifying or inhibiting pain signals within the central nervous system. **Example:** The body can release endorphins to reduce pain perception after an injury, modulating Modulation: Inhibition vs amplification of signal the pain experience. ## Perception **Explanation:** Perception is the conscious awareness of pain, integrating sensory signals with emotional and cognitive factors. Perception: Conscious awareness of pain as a culmination **Example:** Feeling a sharp pain after stepping on a nail, which is influenced by past experiences and current context. of previous processes in the context of the individuals' R experiences.  Headache Usually occurs as a symptom of an underlying disorder. Ninety percent of all headaches are vascular, muscle contraction, or a combination CAUSES Emotional stress or fatigue Environmental stimuli (noise, crowds, or bright lights) Menstruation. Diseases of the scalp, teeth, extracranial arteries, external or middle ear Hypertension Increased intracranial pressure Vasodilators (nitrates, alcohol, and histamine). PATH 200  Headache Pathophysiology Headaches are believed to be associated with constriction and dilation of intracranial and extracranial arteries. Migraine- severe headache generally associated with nausea and/or light and sound sensitivity, certain biochemical abnormalities, including local leakage of a vasodilator polypeptide called neurokinin through the dilated arteries, are thought to occur as well as a decrease in the plasma level of serotonin. Headache may originate from the pain-sensitive structures of the skin, scalp, muscles, arteries, and veins Intracranial mechanisms of headaches include traction or displacement of arteries, venous sinuses, and inflammation or direct pressure on the cranial nerves. PATH 200  Cerebrovascular Accident (CVA)/ Stroke A stroke or brain attack is a sudden focal neurological deficit caused by cerebrovascular disease. A stroke is a syndrome in which the cerebral circulation is interrupted, causing neurological deficits. Cerebral anoxia lasting longer than 10 minutes causes cerebral infarction with irreversible change. Cerebral edema and congestion cause further dysfunction. https://www.youtube.com/watch?v=3oWspN_SvVM Cerebrovascular Accident (CVA)/ Stroke  Cerebrovascular Accident (CVA)/ Stroke A. Ischemic Strokes: Thrombotic – plaque build-up causing narrowing Embolic – dislodged thrombi of plaque, blot clot, and occludes cerebral arteries B. Lacunar Stroke: Ischemic type stroke from occlusions of small arteries deep in the brain. These are less severe strokes and usually have no or less pronounced neurological changes. C. Hemorrhagic: Stroke occurs suddenly; due to extravasation may include severe headache described as “the worst headache of my life” Cerebrovascular Accident (CVA)/ Stroke Manifestation of right brain and left-brain stroke  Meningitis The brain and the spinal cord meninges become inflamed, usually as a result of bacterial or viral infection. Such inflammation may involve all three meningeal membranes— the dura mater, arachnoid, and pia mater. CAUSES: Almost always a complication of bacteremia, especially from pneumonia, empyema, osteomyelitis, and endocarditis Aseptic meningitis possibly resulting from chemicals, a virus, or other agent Other infections associated with its development include sinusitis, otitis media, encephalitis, myelitis, and brain abscess Following trauma or invasive procedures, including skull fracture, Sometimes no causative organism found  Meningitis Pathophysiology ▪ Meningitis commonly begins as an inflammation of the pia mater and arachnoid mater, which may progress to congestion of adjacent tissues and destroy some nerve cells. ▪ The microorganism triggers an inflammatory response in the meninges. ▪ In an attempt to fight the infection, neutrophils gather in the area and produce an exudate in the subarachnoid space, causing the CSF to thicken. ▪ The exudate also exacerbates the inflammatory response, increasing the pressure and edema in the brain. Clinical Findings: fever, chills, headache, vomiting  Multiple sclerosis (MS) A disease of the CNS, causing demyelination of the white matter of the brain and spinal cord and damage to nerve fibers and their targets. CAUSES The exact cause of MS is unknown Theories suggest that a slow-acting or latent viral infection triggers an autoimmune response. PATH 200 https://www.youtube.com/watch?v=Z1ibVlGflPs  Multiple sclerosis (MS) Pathophysiology In MS, sporadic patches of axon demyelination and nerve fiber loss occur throughout the central nervous system (CNS), producing widely disseminated and varied neurologic dysfunction. Clinical Findings muscle dysfunction, speech problems, bladder and bowel disturbances PATH 200  Parkinson’s disease Parkinson’s disease (also known as shaking palsy) characteristically produces progressive muscle rigidity, akinesia, and involuntary tremors. CAUSES The cause of Parkinson’s disease is unknown Dopamine deficiency Exposure to toxins, such as manganese dust or carbon monoxide. PATH 200  Parkinson’s disease Pathophysiology Parkinson’s disease is a degenerative process involving the dopaminergic neurons in the substantia nigra (the area of the basal ganglia that produces and stores the neurotransmitter dopamine). Normally, stimulation of the basal ganglia results in refined motor movement because acetylcholine (excitatory) and dopamine (inhibitory) release are balanced. Degeneration of the dopaminergic neurons and loss of available dopamine leads to an excess of excitatory acetylcholine at the synapse and consequent rigidity, tremors, and bradykinesia. PATH 200  Parkinson’s disease CLINICAL FINDINGS Muscle rigidity, akinesia, and an insidious tremor beginning in the fingers (unilateral pill- roll tremor), Masklike facial expression, Difficulty speaking or swallowing  Seizure disorder Seizures are an abnormal, sudden, excessive discharge of electrical activity within the brain. Epilepsy is a disorder characterized by chronic seizure activity and indicates brain or CNS irritation. Causes include genetic factors, trauma, tumors, circulatory or metabolic disorders, toxicity, and infections. Status epileptics involve a rapid succession of epileptic spasms without intervals of consciousness; it is a potential complication that can occur with any type of seizure, and brain damage may result. Status epilepticus is a severe condition where a seizure lasts more than 5 minutes or multiple seizures occur without recovery between them. It is a medical emergency that can lead to brain damage if not treated promptly https://www.youtube.com/watch?v=WjRIzsy97hk  Seizure disorder CAUSES Anoxia Birth trauma Brain tumors Head injury or trauma Infectious diseases PATH 200  Seizure disorder Pathophysiology On stimulation, the epileptogenic focus fires and spreads electrical current to surrounding cells. These cells fire in turn and the impulse cascades to one side of the brain (a partial seizure), both sides of the brain (a generalized seizure), or specific cortical, subcortical, or brain stem areas. Clinical Findings Recurring seizures PATH 200  REFERENCES: ▪ NORRIS, T. (2019). Porth’s Pathophysiology Concepts of Altered Health States. 10th ed. Wolters Kluwer ▪ Ian Peate, (2021) Fundamentals of applied pathophysiology: an essential guide for nursing & healthcare students. 4th ed. ▪ Hoboken, NJ : Wiley-Blackwell Dignle, M., Mulvihill, M., Zelman, M. & Tompary, E. (2011). Introductory pathophysiology for nursing & healthcare professionals. |Pearson ▪ Nair, M., & Peate, I. (2015). Pathophysiology for nurses at a glance (nursing and healthcare). Publisher: West Sussex, England: John Wiley & Sons, Inc PATH200/MACHS 33