HA

• Miosis

  –constricted pupil
• Neuron/Nerve cell

  -highly specialized cell that sends impulses throughout the body
• How many neurons do we have?

  100 billion neurons
• Nervous system


  • Highly integrated and complex system
  • Two principal parts: the two systems work together to receive an impulse, interpret it, and initiate a response, enabling the individual to maintain a high-level adaptation and homeostasis or balance
• Parts of the nervous system

  • Central Nervous System (CNS)
  • Peripheral Nervous System (PNS)
• Central Nervous System (CNS)


  Brain and spinal cord
• Peripheral Nervous System (PNS)


  Nerves outside the CNS (cranial and spinal nerves)
• Nervous system


  • Responsible for control of cognitive function and both voluntary and involuntary activities
• Neuron


  Basic cell of the nervous system, a highly specialized cell that sends impulses throughout the body. We have approximately 100 billion neurons
• Parts of a neuron

  • Cell body: contains the nucleus (source of information for protein synthesis)
  • Protoplasmic processes / Dendrites: carry impulses toward the cell body
  • Axon: carry impulses away from the cell body
  • Myelin Sheath: tight pack produced by the Schwann cells in the PNS, Oligodendrocytes in CNS
  • Node of Ranvier: periodic gap in the insulating sheath (myelin) on the axon of certain neurons that serves to facilitate the rapid conduction of nerve impulses
  • Axon terminal: axon endings that are somewhat enlarged and often club- or button-shaped. Axon terminals are that part of a nerve cell that make synaptic connections with another nerve cell or with an effector cell (e.g., muscle cell or gland cell)
• Brain


  • Largest portion of the CNS
  • Covered and protected by meninges, the cerebrospinal fluid (CSF), and the bony structure of the skull
• Meninges


  • Dura mater: This is the outer layer, closest to your skull
  • Arachnoid mater: This is the middle layer
  • Pia mater: This is the inner layer, closest to your brain tissue
• Cerebrospinal fluid


  Helps nourish the CNS, but its primary function is to cushion the brain and prevent injury to the brain tissue
• Regions of the cerebrum

  • Frontal lobe
  • Parietal lobe
  • Occipital lobe
  • Temporal lobe
• Frontal lobe


  • Motor functions, helps control voluntary skeletal movement, speech, emotions, and intellectual activities
  • Prefrontal cortex: controls our intellect, complex learning abilities, judgment, reasoning, concern for others, and creation of abstract ideas
• Parietal lobe


  • Sensory functions, conscious awareness of sensation, somatosensory stimuli, including temperature, pain, and shapes
  • Somatosensory: denotes a sensation that occur anywhere in the body
• Occipital lobe


  • Visual functions, contains visual cortex that receives stimuli from the retina and interprets visual stimuli in relation to past experiences
• Temporal lobe


  • Auditory and olfactory functions, interprets auditory stimuli and contains olfactory cortex that transmits impulses related to smell
• Parts of the diencephalon

  • Thalamus
  • Hypothalamus
  • Epithalamus
• Thalamus


  Gateway to cerebral cortex, all inputs channeled to the cerebral cortex are processed by the thalamus
• Hypothalamus


  Automatic control center, influences activities such as BP, HR, force heart contraction, digestive motility, RR, and depth and perception of pain, pleasure, and fear, regulates body temperature, food intake, water balance, and sleep cycles
• Epithalamus


  Helps control mood and sleep cycles, contains choroid plexus where CSF is formed, where pineal gland/body is located
• Parts of the brainstem

  • Midbrain
  • Pons
  • Medulla oblongata
• Brainstem


  • Contains the midbrain, pons, and medulla oblongata
  • Located between the cerebrum and spinal cord
  • Connects pathways between the higher and lower structures
  • Influences BP by controlling vasoconstriction and also regulates RR, depth, and rhythm as well as vomiting, hiccupping, swallowing coughing, and sneezing
• Vasoconstriction


  Constriction of the blood vessels
• Cerebellum


  • Coordinates stimuli from the cerebral cortex to provide precise timing for skeletal muscle coordination and smooth movements
  • Assists with maintaining equilibrium and muscle tone
• Spinal cord


  • Continuation of the medulla, passes through the skull at the foramen magnum and continues through the vertebral column to the first lumbar vertebra (L1 or L2)
  • Meninges, CSF, and bony vertebrae protect the spinal cord
  • Transmit impulses to and from the brain via the ascending and descending pathways
• Cranial nerves

  • CN I Olfactory
  • CN II Optic
  • CN III Oculomotor
  • CN IV Trochlear
  • CN V Trigeminal
  • CN VI Abducens
  • CN VII Facial
  • CN VIII Vestibulocochlear
  • CN IX Glossopharyngeal
  • CN X Vagus
  • CN XI Accessory
  • CN XII Hypoglossal
• Cranial nerves


  • First two pairs originate in the anterior brain, remaining 10 pairs originate in the brain stem
  • The Vagus nerve is the only CN to serve a muscle and body region below the neck
• Spinal nerves

  • 31 pairs of nerves that arise from the spinal cord
  • Categorized by the region of the vertebral column from which they emerged
  • All are mixed nerves because they contain axons of both sensory and motor neurons
  • Grouped into network of plexus: cervical, brachial, lumbar, and sacral
• Cervical plexus


  • Supplies the neck and shoulders, Phrenic Nerve: supplies the diaphragm (major muscle of respiration)
• Brachial plexus


  • Supplies arm and upper back
• Lumbar plexus


  • Supplies the abdomen and leg muscles
• Sacral plexus


  • Supplies nerves to the back of the thigh, most of the lower leg, and the entire foot
• Nursing procedure


  1. Gather and assemble the need equipment and supplies

  2. Introduce self and identify the client

  3. Explain the procedure and ask for consent

  4. Assist the client to wear examination gown if necessary and place in a position appropriate to the procedure

  5. Provide privacy and expose on the area(s)/part(s) to be assessed

  6. Do hand hygiene and don gloves of necessary
• Neurological disorders

  • Depression
  • Schizophrenia
  • Organic brain syndrome
  • Obsessive-compulsive disorder (OCD)
• Schizophrenia


  Chronic, severe mental disorder that affects the way a person thinks, acts, expresses emotions, perceives reality, and relates to others. A major form of psychosis (a person loses contact with reality), dopamine level is increased
• Depression


  • Reactive Depression: we know the reason why we are depressed. Secondary to a bad situation in life
  • Major Depression
• Organic brain syndrome


  Dysfunction associated with disturbance in consciousness, cognition, mood, affect, and behavior in the absence of drugs, infections, or metabolic cause
• Parkinson's disease


  Brain disorder that leads to shaking, stiffness, and difficulty with walking, balance, and coordination, dopamine level is decreased