There are three types of neurons: sensory neurons, relay neurons and motor neurons
Sensory neurons are found in receptors -eyes, ears tongue and skin-. They carry messages to the Central Nervous System -CNS-. They have long dendrites and short axons
Relay neurons are found in the brain and spinal cord; connect the sensory neurons to the motor neurons or other relay neurons. They have short dendrites and long axons
Motor neurons connect the CNS to effectors such as our muscles or glands. They have short dendrites and long axons
Excitation increases the chance of the PSN continuing the message to the next neuron as it makes it more likely to fire -e.g. Glutamate-
Inhibition decreases the chances of the postsynaptic neuron continuing the message to the next neuron as it makes it less likely to fire
