Neurotransmitters can have different effects, as they can either be excitatory or inhibitory. Excitatory neurotransmitters bind to a gated ion channel, which allows for the influx of positively charged [ Select ] ions: This [ Select ] the membrane, resulting in a less negative voltage. This is called an excitatory post-synaptic potential (EPSP). Inhibitory neurotransmitters bind to a gated ion channel, which allows for the influx of negatively charged [ Select ] ions. This [ Select ] the membrane, resulting in a more negative voltage. This is called an inhibitory post-synaptic potential (IPSP).