Divisions of the Nervous System

Central Nervous System Injuries

concussions and spinal cord injuries

Peripheral Nervous System

-consists of all the nerves located outside of the central nervous system -connects nerves to the rest of the body -involved in both voluntary and involuntary actions -43 pairs of nerves -12 pairs originate in the brain -31 pairs orginate in the spinal cord -1 nerve in each pair goes to the left side of the body and the other goes to the right

autonomic nervous system

-controls involuntary actions

Brain

-controls most systems in the body -directs a response after receiving an impulse -sends it back through the spinal cord and out to the peripheral nervous system

Left half of cerebrum

-controls the right side of the body -associated with mathematical skills and logical skills

Somatic nervous system

-controls voluntary actions

Cerebrum

-largest part of brain -interprets input from the senses -controls movement -carries out complex mental processes such as learning and remembering -divided into right and left half -each half controls slightly different mental activities -different areas control different functions

Brain Stem

-lies between the cerebellum and the spinal cord -controls your body's involuntary actions (those occuring automatically--ex: breathing and heartbeat)

How do spinal nerves function?

-like a two-lane highway -impulses travel on the spinal nerve in two directions (to and from the central nervous system) -contains axons of sensory and motor neurons -sensory neurons carry impulses from the body to the central nervous system -motor neurons carry impulses in the opposite direction (from the central nervous system to the body)

Cerebellum

-second largest part of the brain -coordinates the actions of your muscles -helps you keep your balance

Right half of cerebrum

-sends impulses to skeletal muscles on the left side of the body -associated with creativity and artistic ability

The Reflex Pathway (finger touching sharp object)

-sensory neurons detect stimulus -nerve impulses travel to the spinal cord -nerve impulses return to motor neurons and cause muscles to contract -nerve impulses travel to your brain -you feel pain

What are the two groups of nerves in the peripheral nervous system?

-somatic and autonomic

spinal cord injuries

-spinal is cut or crushed -axons are damaged and impulses cannot pass through them -results in paraysis (loss of movement)

Signaling Brain

-takes longer for pain impulses to get to the brain and be interpreted than it does for a reflex action to occur -by the time you feel pain, you've already moved your finger away

Spinal Cord

-thick column of nervous tissue -vertebral column surrounds and protects it -also protected by watery fluid and layers of connective tissue (same as brain) -links brain to most of the nerves in the peripheral nervous system -most impulses from the peripheral nervous system travel through here to get to the brain

concussions

-a bruise like injury of the brain -occurs when the soft tissue of the brain collide against the skull -bump head, contact sports, car accident -cause headache, drowsiness, confusion, lose consciousness -wear a helmet

Reflex

-an automatic response that occurs very rapidly without conscious control -help protect the body

What are the 3 main regions of the brain that receive and process information?

-cerebrum -cerebellum -brain stem

Central Nervous System

-consists of the brain and the spinal cord -control center of the body

What are the 2 divisions of the nervous system?

Central and Peripheral