NMDA (N-methyl-D-aspartate) receptors are a type of receptor in the brain that play a crucial role in synaptic plasticity, which is important for learning and memory. They are a subtype of glutamate receptors, as they are activated by the neurotransmitter glutamate, which is the primary excitatory neurotransmitter in the central nervous system. NMDA receptors are unique because they are both ligand-gated and voltage-dependent. This means they require the binding of glutamate and a change in the electrical potential of the cell membrane to become active.
Neurons in the brain can be broadly classified into excitatory and inhibitory types based on the type of neurotransmitters they release and the effect they have on target neurons. Excitatory Neurons: These neurons release excitatory neurotransmitters, like glutamate, which increase the likelihood that the target neuron will fire an action.