The politics of identity is a kind of cultural politics. It relies on the development of a culture that is able to create new and affirmative conceptions of the self, to articulate collective identities, and to forge a sense of group loyalty.
Neurons transmit electrical impulses by allowing the passage of charged ions across their membranes in response to stimuli, changing the charge of the neuron in a process that propagates through the axon of the neuron. Normally, neurons maintain an internal negative charge relative to their environment by excluding sodium ions from their cytoplasm.
Nerve cells need to be able to send messages to each other quickly and clearly. One way that nerve cells communicate with their neighbors is by sending a burst of small neurotransmitter molecules. These molecules diffuse to the neighboring cell and bind to special receptor proteins in the cell surface. These receptors then open, allowing ions to flow inside. The process is fast because the small neurotransmitters, such as acetylcholine or serotonin, diffuse rapidly across the narrow synapse between the cells.