The nervous system is composed of two major types of cells—nerve cells, or neurons, which process information and rapidly convey information; and—glial cells which serve as supporting cells of the nervous system. Neurons create neural networks by connecting to each other to facilitate communication. The dendrites are processes that receive information from various sources, such as the sensory epithelial cells, or other neurons. Thereby, neurons usually receive information through their dendrites and cell bodies and transmit it via their axons to other neurons via their synapses. Sensory neurons are involved in the reception of sensory stimuli by being either directly responsive to stimuli such as touch or temperature changes or receiving direct connections from non-neuronal receptor cells. Glutamatergic neurons are neurons that use glutamic acid, glutamate, as a neurotransmitter. The major sources of dopamine in the mammalian central nervous system are the dopaminergic neurons located at midbrain.