Neurons are charged cells: they conduct electrical signals to pass information through the body. A typical neuron consists of a cell body, dendrites, and an axon with an axon terminal.
The dendrites receive signals from body tissues or other neurons and pass them into the cell body. If an outgoing signal is produced, it zips down the axon to the axon terminal and passes to the next neuron or target cell.
This conductive capability sends information up and down nerve pathways and through the central nervous system at incredible speed. Some billion neurons give the brain its awesome processing power. Nervous system messages travel through neurons as electrical signals.
When these signals reach the end of a neuron, they stimulate the release of chemicals called neurotransmitters. Neurotransmitters travel across synapses , spaces between neurons or between neurons and other body tissues and cells. Neurotransmitters can be classified as two types: excitatory or inhibitory. Excitatory neurotransmitters stimulate electrical signals in other neurons and encourage responses from body cells.
Inhibitory transmitters discourage signals and cellular responses. Through these chemicals, the nervous system regulates the activity of muscles, glands, and its own nerve pathways. The spinal cord is an elongated cylinder of neuron cell bodies, bundles of axons and other cells, protected by connective tissue and bone. It connects to the brain at the medulla oblongata and runs down the vertebral column, the hollow tunnel enclosed within the vertebrae of the spine.
The spinal cord is part of the central nervous system and serves as a kind of superhighway. It also obeys commands from the central nervous system and makes muscles contract or relax, allowing us to move. This page has been produced in consultation with and approved by:.
The long-term effects of brain injury will be different for each person and can range from mild to profound. A person with alcohol related brain impairment ARBI might experience problems with coordination, thinking, planning and memory. If a person with alcohol related brain impairment is aware of their memory limits, they can learn how to deal with them.
People with alcohol related brain impairment benefit when their life is organised and follows a good structure. Loss of memory can be temporary or permanent, but 'amnesia' usually refers to the temporary variety. Content on this website is provided for information purposes only. Information about a therapy, service, product or treatment does not in any way endorse or support such therapy, service, product or treatment and is not intended to replace advice from your doctor or other registered health professional.
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The State of Victoria and the Department of Health shall not bear any liability for reliance by any user on the materials contained on this website. Skip to main content. Brain and nerves. Home Brain and nerves. Nervous system. Actions for this page Listen Print. Summary Read the full fact sheet. On this page. Neurones are the building blocks Central nervous system The peripheral nervous system Problems of the nervous system Where to get help Things to remember.
Neurones are the building blocks The basic building block of the nervous system is a nerve cell, or neurone. Central nervous system The brain and the spinal cord make up the central nervous system. Along the way, nerves branch out to the entire body. The brain and the spinal cord are protected by bone: the brain by the bones of the skull, and the spinal cord by a set of ring-shaped bones called vertebrae. They're both cushioned by layers of membranes called meninges and a special fluid called cerebrospinal fluid.
This fluid helps protect the nerve tissue, keep it healthy, and remove waste products. The forebrain is the largest and most complex part of the brain. It consists of the cerebrum — the area with all the folds and grooves typically seen in pictures of the brain — as well as other structures under it. The cerebrum contains the information that essentially makes you who you are: your intelligence, memory, personality, emotion, speech, and ability to feel and move.
Specific areas of the cerebrum are in charge of processing these different types of information. These are called lobes, and there are four of them: the frontal, parietal, temporal, and occipital lobes.
The cerebrum has right and left halves, called hemispheres. They're connected in the middle by a band of nerve fibers the corpus callosum that lets them communicate. These halves may look like mirror images of each other, but many scientists believe they have different functions:.
So when you're balancing your checkbook, you're using the left side. When you're listening to music, you're using the right side. It's believed that some people are more "right-brained" or "left-brained" while others are more "whole-brained," meaning they use both halves of their brain to the same degree. The outer layer of the cerebrum is called the cortex also known as "gray matter". Information collected by the five senses comes into the brain to the cortex.
This information is then directed to other parts of the nervous system for further processing. For example, when you touch the hot stove, not only does a message go out to move your hand, but one also goes to another part of the brain to help you remember not to do that again.
In the inner part of the forebrain sits the thalamus, hypothalamus, and pituitary gland :. The midbrain, underneath the middle of the forebrain, acts as a master coordinator for all the messages going in and out of the brain to the spinal cord.
The hindbrain sits underneath the back end of the cerebrum. It consists of the cerebellum, pons, and medulla. The cerebellum — also called the "little brain" because it looks like a small version of the cerebrum — is responsible for balance, movement, and coordination. The pons and the medulla, along with the midbrain, are often called the brainstem.
The brainstem takes in, sends out, and coordinates the brain's messages. It also controls many of the body's automatic functions, like breathing, heart rate, blood pressure, swallowing, digestion, and blinking. The basic workings of the nervous system depend a lot on tiny cells called neurons. The brain has billions of them, and they have many specialized jobs. For example, sensory neurons send information from the eyes, ears, nose, tongue, and skin to the brain.
Motor neurons carry messages away from the brain to the rest of the body. All neurons relay information to each other through a complex electrochemical process, making connections that affect the way you think, learn, move, and behave.
Intelligence, learning, and memory.
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