Nervous System Different parts of nervous system are divided by where the nerves are located and what areas of the body are involved
Central Nervous System Definition: the brain and spinal cord
Spinal Cord Definition: part of the body that functions as an automatic “brain” in its own right and as a relay station for impulses to and from the higher brain In theory: spinal cord could operate by itself if different parts of the body were stimulated – Frog experiment
Reflex Definition: an automatic behavior of the body involving movement that is activated through the spinal cord without use of the cerebral cortex – Provide an “automatic” protective device for the body Examples: close call while driving, putting hand on hot stove
Peripheral Nervous System All the nerves outside the brain and spinal cord Divided into Somatic nervous system and autonomic nervous system
Somatic Nervous System Definition: A division of the peripheral nervous system containing sensory and motor nerves – Sensory Nerves: pick up information and relays it to the brain and spinal cord – Motor Nerves: get instructions from the brain and spinal cord and put our muscles into action
Autonomic Nervous System Definition: the autonomic control system of the body; regulates breathing, heart rate, digestion, and so on – Autonomic: independent or functioning on its own (THINK AUTOPILOT)
Sympathetic Nervous System Definition: a division of the autonomic nervous system that energizes and prepares for emergencies An accelerator for emergency situations
Sympathetic Nervous System Tries to stay in balance, but can be overridden by the higher brain – Taking a big exam Emotional response triggered by cerebral cortex Heart speeds up Blood pressure increases Liver becomes highly active to provide sugar to muscles Stomach slows Pupils dilate
Parasympathetic Nervous System Definition: division of the autonomic nervous system that conserves bodily activity; works in opposition to the sympathetic system to calm us own A natural breaking mechanism to bring things back to normal