The NMDA receptor is a receptor in the central nervous system that is responsible for initiating downstream effects using neurotransmitters. In order for the NMDA receptor to be activated, glutamate and glycine need to be activated. Then, the magnesium molecule has to be removed from the pore of the receptor. This type of receptor plays a significant role in a variety of neurological processes, including synaptic plasticity, learning, and memory. The receptor can be triggered by a wide variety of psychoactive drugs including ketamine and PCP. When the receptor is activated, it opens, allowing ions to pass through the membrane. As ions pass through the membrane, various neurotransmitters are released, causing changes in how people feel.