Glial cells are smaller than neurons but are greater in number than nerve cells in the brain. © 2016 Wiley Periodicals, Inc. Neurons are cells that send and receive electro-chemical signals to and from the brain and nervous system. J. Comp. Glial cells are much smaller than neurons and we have many more glial cells than neurons. Figure \(\PageIndex{1}\): (CC BY 2.5; By Wei-Chung Allen Lee, Hayden Huang, Guoping Feng, Joshua R. Sanes, Emery N. Brown, Peter T. “In a sense, glial cells are taking the pulse of neurons in a wide area.” Brain and Beyond. We also discuss implications and consequences of the new insights into true numbers of glial cells in the human brain, and the promise and potential impact of the newly validated isotropic fractionator for reliable quantification of glia and neurons in neurological and psychiatric diseases. There are different types of glial cell, each of which plays a different role in supporting the neurons. There are about 100 billion neurons in the brain. They vary in size from 4 microns (.004 mm) to 100 microns (.1 mm) in diameter. 524:3865–3895, 2016. Newman will repeat this work in the brain to find out how much capillary dilation contributes to overall blood flow. They have traditionally been ascribed supportive roles in the nervous system, and number on average roughly equal to the 86 billion neurons in the adult brain. There are many type of neurons. There are several types of glial cells. The main ones are listed below. Neurol. The neuron is one of two basic types of cells in the nervous system, the other type being the glial cell. Glial cells do not have axon and dendrites. Glial cells support and protect the neurons, provide the neurons with oxygen and nutrients, and remove dead cells. First, an explanation of glial cells is in order. They are, after all, the primary cells of the nervous system, responsible for conducting electrical currents to encode and process our senses, thoughts, memories and emotions. Smarter brain ‘glue’ — glia cells take the spotlight Many neuroscientists will tell you that nerve cells in the brain (called neurons) are the most important part of the nervous system. Their length … “A glial cell can sense the activity of many neurons in its neighborhood,” Newman notes. There are many more glial cells; they provide support functions for the neurons, and are far more numerous than neurons.