How the Nervous System Works
- The nervous system coordinates all activities
- Your nervous system is a complex network that allows communication between the brain and body
- The brain, spine, and nerves work together, transmitting messages between organs, tissues, and cells.
Central Nervous System v. Peripheral Nervous System
The central nervous system (CNS) consists of the brain and spinal cord
- The CNS receives messages from the nerves and in the PNS, interprets them, and sends out a response
The peripheral nervous system (PNS) gathers information from inside and outside your body
- The PNS includes nerves that extend from the brain, spinal cord, and sensory receptors, such as those in the skin
Understanding Neurons
- Sensory Neurons: Carry messages from receptors in the body to the CNS
- Motor Neurons: Carry messages from the CNS back to muscles or glands in response to an impulse
- Internuerons: Communicate with connect other neurons
Central Nervous System
Peripheral Nervous System (PNS)
- The peripheral nervous system is made up of the nerves that are not in the brain and spinal cord
- The PNS carries messages between the CNS and parts of the body
Autonomic Nervous System
- The autonomic nervous system control such involuntary functions as digestion and heart rate
- A reflex is the body’s spontaneous response to stimulus
Somatic Nervous System
- The somatic nervous system involves voluntary responses that are under your control
- Sensory neurons relay messages from the eyes, ears, nose, tongue, and skin to the CNS, and motor neurons carry impulses from the CNS to skeletal muscles
Caring For your Nervous System
- Eat a well-balanced diet
- Exercise regularly
- Get enough sleep
- Wear a safety belt when in a motor vehicle
- Never die into shallow water
- Wear a helmet and other protective gear while riding a bicycle, motorcycle, or other open vehicle, or when playing a contact sport
- Avoid using drugs an alcohol
Problems of the Nervous System
Headaches: can be caused by muscle tension, eyestrain, exposure to fumes, a sinus infection, dehydration, or food allergies
Head Injuries
- Concussion: Cause by a bump, blow, or jolt to the head or by a hit to the body that causes the head and brain to move rapidly back and forth
- Contusion: A bruising of the brain tissues that causes swelling
- Coma: A state of unconsciousness caused by major trauma
Spinal Injury: Swelling of the spinal cord or tissue around it can result in temporary loss of nerve function. If the spinal cord is severed, paralysis results
Meningitis: An inflammation of spinal and cranial meninges caused by bacterial or viral infection
Degenerative Diseases: occur over time as cells break down