APA Dictionary of Psychology

a type of glutamate receptor that binds NMDA as well as glutamate. NMDA receptors are coupled to ligand-gated ion channels and are also voltage-sensitive, which enables them to participate in a variety of information-processing operations at synapses where glutamate is the neurotransmitter. The drugs of abuse ketamine and PCP are antagonists at NMDA receptors, preventing the influx of calcium ions at calcium channels, which may cause the hallucinogenic effects of these drugs. Excessive flow of calcium ions into the presynaptic neuron via the NMDA receptor is thought to contribute to glutamate toxicity. A hypothesis on the etiology of schizophrenia involves dysfunction of the NMDA glutamate receptor (see glutamate hypothesis). Compare AMPA receptor.