ANAPHYSIO

• The right half of the brain controls the left half of the body. This means that only left handed people are in their right mind.
• Central Nervous System


  Made up of brain and spinal cord, acts as body's control center, coordinates body's activities, impulses travel through neurons in your body to reach the brain
• Peripheral Nervous System


  Made up of all the nerves that carry messages to and from the central nervous system, similar to telephone wires that connect all our houses in the community
• Central Nervous System and Peripheral Nervous System


  Work together to make rapid changes in your body in response to stimuli
• Parts of Peripheral Nervous System

  • Somatic Nervous System
  • Autonomic Nervous System
• Somatic Nervous System


  Relay information between skin, skeletal muscles and central nervous system, you consciously control this pathway by deciding whether or not to move muscles (except reflexes)
• Reflexes


  Automatic response to stimulus
• Autonomic Nervous System


  Relay information from central nervous system to organs, you do not consciously control these
• Parts of Autonomic Nervous System

  • Sympathetic Nervous System (controls in times of stress, such as the flight or fight response)
  • Parasympathetic Nervous System (controls body in times of rest)
• Neurons


  The basic unit of structure and function in the nervous system, cells that conduct impulses, made up of dendrites, cell body and an axon
• Dendrites


  • Branch-like extensions that receive impulses and carry them toward cell body
• Axon


  • Single extension of the neuron that carries impulses away from the cell body, branches out at ending to send impulses to many different neurons
• There's a lot of traffic going on in the neurons of your Central Nervous System
• Types of neurons


  • Sensory Neurons (carry impulses from inside and outside the body to brain and spinal cord)
  • Interneurons (found within brain and spinal cord, process incoming impulses and pass them on to motor neurons)
  • Motor Neurons (carry impulses away from the brain and spinal cord)
• How neurons work when someone taps you on the shoulder

  Receptors in the skin sense touch or other stimuli, sensory neurons transmit the touch message, information is sorted and interpreted in the brain, a response is determined by interneurons, motor neurons transmit a response message to the shoulder muscles, the shoulder muscles are activated, causing the head to turn
• How an impulse is transmitted

  Stimulus excites sensory neuron, depolarization creates a wave of changing charges down the axon, impulse moves across synapse with the help of neurotransmitters
• Reflexes


  Rapid, predictable and involuntary responses to stimuli, occur over neural pathway called reflex arcs and involve both CNS and PNS structures
• Types of reflexes


  • Somatic reflexes (include all reflexes that stimulate the skeletal muscles)
  • Autonomic reflexes (regulate the activity of smooth muscles, the heart, and glands)
• Central Nervous System


  • Neural tube - a simple tube wherein the CNS first appear during embryonic development, ventricles - chambers formed by the enlarged four regions of the brain, brain - about two good fistfuls of pinkish gray tissue, wrinkled like a walnut and with the texture of cold oatmeal, weighs a little over three pounds, cerebral hemispheres - the paired cerebral hemispheres, collectively called the cerebrum, gyri - elevated ridges of tissue in the entire surface of cerebral hemispheres
• Spinal Cord


  • Approximately 17 inches (42 cm) long, extends from the foramen magnum to the first or second lumbar vertebra, 31 pairs of spinal nerves, enlarged in cervical and lumbar regions, cauda equina - collection of spinal nerves at the inferior end of the vertebral canal that looks so much like a horse's tail
• Gray Matter of the Spinal Cord and Spinal Roots

  • Looks like a butterfly or the letter H in cross section, two posterior projections are the dorsal/posterior horns, two anterior projections are the ventral/anterior horns, surrounds the central canal of the cord which contains CSF, dorsal root ganglion - when damaged, sensation from the body area served will be lost, dorsal and ventral roots fuse to form the spinal nerves
• Structure of a Nerve

  • Nerve - a bundle of neuron fibers found outside the CNS, endoneurium - connective tissue sheath that surrounds each fiber, perineurium - coarser connective tissue that wraps groups of fibers (fascicles), epineurium - a tough fibrous sheath that bound all the fascicles together
• Sulci - shallow grooves, Fissures - deeper grooves, separate large regions of the brain, Longitudinal fissure - single deep fissure
• Nerve


  A bundle of neuron fibers found outside the CNS
• Structure of a Nerve

  • Endoneurium - connective tissue sheath that surrounds each fiber
  • Perineurium - coarser connective tissue that wraps groups of fibers (fascicles)
  • Epineurium - a tough fibrous sheath that bound all the fascicles together
• Sulci


  Shallow grooves
• Fissures


  Deeper grooves, separate large regions of the brain
• Longitudinal fissure


  Single deep fissure that separates the cerebral hemispheres
• Cerebral Cortex


  • Speech, memory, logical and emotional response, as well as consciousness, interpretation of sensation, and voluntary movement
• Primary somatic sensory area


  Located in the parietal lobe posterior to the central sulcus. For recognition of pain, coldness, or light touch.
• Occipital lobe


  The visual area
• Temporal lobe


  Auditory area, the olfactory area is found deep inside
• Primary motor area


  Allows us to consciously move our skeletal muscles, anterior to the central sulcus in the frontal lobe
• Corticospinal tract/pyramidal tract


  The major voluntary motor tract
• Motor homunculus


  Body map of the motor cortex
• Broca's area


  Found at the base of the precentral gyrus. Damage to this area causes inability to say words properly.
• Frontal lobe


  Higher intellectual reasoning and socially acceptable behavior
• Temporal and frontal lobes


  Storage of complex memories
• Wernicke's area


  Speech area located at the junction of the temporal, parietal, and occipital lobes
• Corpus callosum


  Large fiber tract that connects the cerebral hemispheres