What is the role of an excitatory neurotransmitter?

An excitatory neurotransmitter primarily functions to increase the likelihood of an action potential occurring in a neuron. When such a neurotransmitter is released into the synaptic cleft and binds to receptors on the postsynaptic neuron, it typically causes depolarization. This depolarization may elevate the membrane potential to a threshold level, which triggers the opening of voltage-gated sodium channels, leading to the initiation of an action potential.

This effect is crucial for communication between neurons, enabling the propagation of signals throughout the nervous system. By enhancing the activity of neurons, excitatory neurotransmitters play a vital role in functions such as learning, memory, and overall brain function.