Ionotropic receptors are a type of membrane protein that function as channels for ions. When a specific neurotransmitter binds to these receptors, they undergo a conformational change, allowing ions such as sodium, potassium, calcium, or chloride to flow across the cell membrane. This rapid movement of ions can lead to changes in the electrical potential of the cell, influencing neuronal signaling. These receptors play a crucial role in synaptic transmission, particularly in the central nervous system. Examples of ionotropic receptors include NMDA receptors and AMPA receptors, which are important for processes like learning and memory. Their fast response times make them essential for quick communication between neurons.