In the nervous system, a synapse is a structure that permits a neuron to pass an electrical or chemical signal to another cell (neural or otherwise). Santiago Ramón y Cajal proposed that neurons are not continuous throughout the body, yet still communicate with each other, an idea known as the neuron doctrine.. The word "synapse" comes from "synaptein", which Sir Charles Scott Sherrington and colleagues coined from the Greek "syn-" ("together") and "haptein" ("to clasp").

Synapses are essential to neuronal function: neurons are cells that are specialized to pass signals to individual target cells, and synapses are the means by which they do so. At a synapse, the plasma membrane of the signal-passing neuron (the presynaptic neuron) comes into close apposition with the membrane of the target (postsynaptic) cell. Both the presynaptic and postsynaptic sites contain extensive arrays of molecular machinery that link the two membranes together and carry out the signaling process. In many synapses, the presynaptic part is located on an axon, but some presynaptic sites are located on a dendrite or soma. Astrocytes also exchange information with the synaptic neurons, responding to synaptic activity and, in turn, regulating synaptic transmission.

Rain Phoenix (born November 21, 1972) is an American actress, musician, and singer. Phoenix has four siblings: two brothers, actors Joaquin and the late River Phoenix, and two sisters, Summer and Liberty.

Phoenix was born Rain Joan of Arc (according to the State of Texas Texas Birth Index, 1903-1997 Ancestry.com) in Crockett, Texas, the second child of John Lee Bottom and Arlyn Sharon (née Dunetz). Her mother was born in the Bronx, New York to Jewish parents from Hungary and Russia. Her father was a lapsed Catholic from Fontana, California. In 1968, Phoenix's mother left her family and moved to California, meeting Phoenix's father while hitch-hiking. They married in 1969 and joined Children of God and worked as missionaries in South America. It was there, at the age of three, that Phoenix (accompanied by elder brother River on guitar) first began to sing. Soon the other Phoenix children joined them and they would perform on the streets of Caracas, Venezuela for loose change while handing out Christian flyers to passers by. The family set out for California in order for the children to enter the entertainment industry. In West Los Angeles, Phoenix and her siblings would perform on the streets for crowds of people. Arlyn took a job at NBC and eventually secured all five Phoenix children with an agent.