The Neurobiology of Drug Addiction

Describe the synapse and the process of chemical neurotransmission. As an electrical impulse arrives at the terminal, it triggers vesicles containing a neurotransmitter, such as dopamine (in blue), to move toward the terminal membrane. The vesicles fuse with the terminal membrane to release their contents (in this case, dopamine). Once inside the synaptic cleft (the space between the two neurons) the dopamine can bind to specific proteins called dopamine receptors (in pink) on the membrane of a neighboring neuron. This is illustrated in more detail on the next image.