PCBI101: NERVOUS

• Alpha-1 receptors


  Elicit response from Ca+ second messenger system, an excitatory response, present in most sympathetic target tissues (e.g. vasoconstriction due to contraction of smooth muscle)
• Alpha-2 receptors


  Block cAMP production, an inhibitory response (e.g. decreased smooth muscle contraction in digestive tract)
• Types of sleep

  • Non-rapid eye movement (NREM)
  • Rapid eye movement (REM)
• Memory


  The parts of brain by which data or information is encoded, stored, and retrieved when needed, for the purpose of influencing future action
• Grey matter


  Contains the cell bodies (perikarya) of neurons and the supporting cells (neuroglia) as well as unmyelinated dendrites
• White matter


  Does not contain any cell bodies, but mostly contains myelinated nerve fibres
• Senses

  • General senses (somatic and visceral)
  • Special senses (vision, hearing, balance, taste, smell)
• Somatic senses


  Provide sensory information about the body and environment, including touch, pressure, temperature, proprioception and pain
• Visceral senses


  Provide information about various internal organs, consist primarily of pain and pressure
• Special senses


  More specialized in structure and located in specific parts of the body, including vision, hearing, balance, taste, and smell
• Sensation


  Conscious awareness of stimuli received by sensory receptors
• Two Basic Groups of Senses

  • General senses
  • Special senses
• General senses


  • Have simple receptors, distributed throughout the body to detect internal and external environmental conditions
• Types of General Senses

  • Somatic senses (touch, pressure, temperature, proprioception, pain)
  • Visceral senses (pain, pressure)
• Special senses


  • More specialized in structure, located in specific parts of the body
  • Include vision, hearing, balance, taste, smell
• Sensory Receptors


  Specialized nerve cells that respond to a stimulus in the internal or external environment by generating a nerve impulse, then travels along the sensory (afferent) nerve to the central nervous system for processing and forming a response
• Types of Sensory Receptors

  • Mechanoreceptors (respond to mechanical forces)
  • Thermoreceptors (respond to temperature changes)
  • Photoreceptors (detect and respond to light)
  • Chemoreceptors (respond to chemicals)
  • Nociceptors (respond to chemical, thermal or mechanical stimuli)
• Pain


  An unpleasant sensation that can range from mild, localized discomfort to agony
• Types of Pain

  • Phantom pain
  • Acute pain
  • Chronic pain
  • Sensitization in Chronic pain (peripheral, central)
  • Referred pain
  • Visceral pain
  • Somatic pain
• The Eye


  • Eyes are the body's most highly developed sensory organs, 80% of what we perceive comes through our sense of sight
  • Protecting our eyes will reduce the odds of blurring vision and developing eye disease
• Visual Acuity


  The person's ability to discern the shapes and details of things
• Visual Acuity Test


  An eye exam that checks how well a person sees the details of a letter or symbol from a specific distance
• The Ear


  • Responsible for hearing and maintaining balance/equilibrium
  • Two types of equilibrium: static (sense of gravity) and kinetic (sense of speed and direction of motion)
• Rinne Test


  1. Compares perception of sounds transmitted by air conduction to those transmitted by bone conduction to screen for conductive hearing loss

  2. Should be accompanied by a Weber Test to also detect sensorineural hearing loss
• Romberg Test


  • A test used to examine neurological function for balance, and also as a test for driving under the influence
  • Assesses the person's ability to maintain balance using proprioception, vestibular function, and vision
• Brain (CNS)

  • Perception and processing of sensory stimuli (somatic/autonomic).
  • Execution of voluntary motor responses (somatic)
  • Regulation of homeostatic mechanisms (autonomic)
• Spinal Cord (CNS)

  • Initiation of reflexes from ventral horn (somatic) and lateral horn (autonomic) gray matter
  • Pathways for sensory and motor functions between periphery and brain (somatic/autonomic)
• Nerves (PNS)

  Fibers of sensory and motor neurons (somatic/autonomic)
• Digestive tract (ENS)

  • The Enteric Nervous System (ENS), located in the digestive tract, is responsible for autonomous functions and can operate independently of the brain and soinal cord
• Ganglia (PNS)

  • Reception of sensory stimuli by dorsal root and cranial ganglia (somatic/autonomic)
  • Relay visceral motor responses by autonomic ganglia (autonomic)
• Neurons - excitable;receive, process, transmit information
• Microglia - innate and immunity
• Astrocytes - Maintain BBB integrity; participate in synapses
• Ependymal - Build barriers between compartments
• Oligodendrocytes - Produce myelin sheaths
• CNS System Cells

  • Neurons
  • Microglia
  • Astrocytes
  • Ependymal
  • Oligodendrocytes
• PNS Cells

  • Neurons
  • Satellite
  • Schwann
• Stellite - Support other cells
• Schwann - Produce myelin sheats around axons
• Left part of the Brain

  • Logic skills
  • Daily activities
  • Language and grammar
  • Memory
  • Analytic and Detail
  • Science
  • Strategy
  • Facts
  • Words of songs