Briefly outline how excitation and inhibition are involved in synaptic transmission (4 marks)

If neurotransmitters are excitatory then they increase the positive charge of the neuron, making it more likely to fire. An example of this is dopamine, of which high amounts are linked to schizophrenia. Whereas, if a neurotransmitter is inhibitory, such as serotonin, it will result in the neuron becoming more negatively charged and less likely to fire.