what is neuron in psychology?

It is clear that most of what we think of as our mental life involves the activities of the nervous system, especially the brain. This nervous system is composed of billions of cells, the most essential being the nerve cells or neurons. There are estimated to be as many as 100 billion neurons in our nervous system!

A typical neuron has all the parts that any cell would have, and a few specialized structures that set it apart. The main portion of the cell is called the soma or cell body. It contains the nucleus, which in turn contains the genetic material in the form of chromosomes.

Neurons have a large number of extensions called dendrites. They often look likes branches or spikes extending out from the cell body. It is primarily the surfaces of the dendrites that receive chemical messages from other neurons.

One extension is different from all the others, and is called the axon. Although in some neurons, it is hard to distinguish from the dendrites, in others it is easily distinguished by its length. The purpose of the axon is to transmit an electro-chemical signal to other neurons, sometimes over a considerable distance. In the neurons that make up the nerves running from the spinal cord to your toes, the axons can be as long as three feet!

Longer axons are usually covered with a myelin sheath, a series of fatty cells which have wrapped around an axon many times. These make the axon look like a necklace of sausage-shaped beads. They serve a similar function as the insulation around electrical wire.

At the very end of the axon is the axon ending, which goes by a variety of names such as the bouton, the synaptic knob, the axon foot, and so on (I do not know why no one has settled on a consistent term!). It is there that the electro-chemical signal that has travelled the length of the axon is converted into a chemical message that travels to the next neuron.

Between the axon ending and the dendrite of the next neuron is a very tiny gap called the synapse (or synaptic gap, or synaptic cleft), which we will discuss in a little bit. For every neuron, there are between 1000 and 10,000 synapses.

A neuron is a nerve cell that is the basic building block of the nervous system. Neurons are similar to other cells in the human body in a number of ways, but there is one key difference between neurons and other cells. Neurons are specialized to transmit information throughout the body.

These highly specialized nerve cells are responsible for communicating information in both chemical and electrical forms. There are also several different types of neurons responsible for different tasks in the human body.

Sensory neurons carry information from the sensory receptor cells throughout the body to the brain. Motor neurons transmit information from the brain to the muscles of the body. Interneurons are responsible for communicating information between different neurons in the body.

Neurons vs. Other Cells

Similarities with other cells:

Neurons and other body cells both contain a nucleus that holds genetic information.

Neurons and other body cells are surrounded by a membrane that protects the cell.

The cell bodies of both cell types contain organelles that support the life of the cell, including mitochondria, Golgi bodies, and cytoplasm.

Differences that make neurons unique:

Unlike other body cells, neurons stop reproducing shortly after birth. Because of this, some parts of the brain have more neurons at birth than later in life because neurons die but are not replaced. While neurons do not reproduce, research has shown that new connections between neurons form throughout life.

Neurons have a membrane that is designed to sends information to other cells. The axon and dendrites are specialized structures designed to transmit and receive information. The connections between cells are known as a synapses. Neurons release chemicals known as neurotransmitters into these synapses to communicate with other neurons.

The Structure of a Neuron

There are three basic parts of a neuron: the dendrites, the cell body and the axon. However, all neurons vary somewhat in size, shape, and characteristics depending on the function and role of the neuron. Some neurons have few dendritic branches, while others are highly branched in order to receive a great deal of information. Some neurons have short axons, while others can be quite long. The longest axon in the human body extends from the bottom of the spine to the big toe and averages a length of approximately three feet!