nervous

• Nervous System


  A system that controls all of the activities of the body
• Major divisions of the Nervous System

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

  Comprised of the brain and spinal cord
• Peripheral Nervous System (PNS)


  Comprised of the nerves
• Central Nervous System


  • It Controls all of the body's activities
• Parts of the brain

  • Forebrain
  • Midbrain
  • Hindbrain
• Forebrain


  Develops into cerebrum and underlying structures
• Midbrain


  Becomes part of the Brainstem
• Hindbrain


  Gives rise to regions of the brainstem and the cerebellum
• Brain


  Command center for the human nervous system
• The brain weighs about 3.3 lbs. (1.5 kilograms), about 2 % of a human's body weight
• The brain contains about 86 billion nerve cells (neurons) - the "gray mater"
• The brain contains billions of nerve fibers (axons and dendrites) - the "white mater"
• Brain


  Receives information through our five senses: sight, smell, touch, taste, and hearing - often many at one time
• Brain


  Assembles the messages in a way that has meaning for us, and can store that information in our memory
• Brain


  Controls our thoughts, memory and speech, movement of the arms and legs, and the function of many organs within our body
• Cerebellum


  Its function is to coordinate muscle movements, maintain posture, and balance
• Brainstem


  Acts as a "relay center" connecting the cerebrum and cerebellum to the spinal cord
• Brainstem


  Performs many automatic functions such as breathing, heart rate, body temperature, wake and sleep cycles, digestion, sneezing, coughing, vomiting, and swallowing
• Cerebrum


  Is the largest part of the brain
• Cerebrum


  Composed of right and left hemispheres
• Cerebrum


  Performs higher functions like interpreting touch, vision and hearing, as well as speech, reasoning, emotions, learning, and fine control of movement
• Corpus Callosum


  Bundle of fibers that joins the right and left hemispheres of cerebrum
• Corpus Callosum


  Transmits messages from one side to the other
• Each hemisphere controls the opposite side of the body
• If a stroke occurs on the right side of the brain, your left arm or leg may be weak or paralyzed
• Left hemisphere ("dominant hemisphere)


  Controls speech, comprehension, arithmetic, and writing
• Right hemisphere


  Controls creativity, spatial ability, artistic, and musical skills
• The left hemisphere is dominant in hand use and language in about 92% of people
• Lobes of the brain

  • Frontal
  • Temporal
  • Parietal
  • Occipital
• Frontal lobe


  • Personality, behavior, emotions
  • Judgment, planning, problem solving
  • Speech: speaking and writing (Broca's area)
  • Body movement (motor strip)
  • Intelligence, concentration, self awareness
• Parietal lobe


  • Interprets language, words
  • Sense of touch, pain, temperature (sensory strip)
  • Interprets signals from vision, hearing, motor, sensory and memory
  • Spatial and visual perception
• Occipital lobe


  Interprets vision (color, light, movement)
• Temporal lobe


  • Understanding language (Wernicke's area)
  • Memory
  • Hearing
  • Sequencing and organization
• Aphasia


  A disturbance of language affecting speech production, comprehension, reading or writing, due to brain injury – most commonly from stroke or trauma
• Broca's Aphasia


  Difficulty moving the tongue or facial muscles to produce the sounds of speech. The person can still read and understand spoken language but has difficulty in speaking and writing (i.e. forming letters and words, doesn't write within lines)
• Wernicke's aphasia


  The individual may speak in long sentences that have no meaning, add unnecessary words, and even create new words. They can make speech sounds, however they have difficulty understanding speech and are therefore unaware of their mistakes
• Cerebral Cortex


  • Gray Matter – the gray-brown layer containing the nerve cell bodies
  • White Matter – lies beneath the gray matter containing long nerve fibers (axons) that connect brain areas to each other
• The folded surface of the cerebrum contains 16 billion neurons (the cerebellum has 70 billion = 86 billion total) that are arranged in specific layers
• Gyrus


  Fold on the surface