Action potentials are rapid, transient changes in the electrical potential across a neuron's membrane. They propagate along the axon, allowing information to be transmitted over long distances within the nervous system.
Neurotransmitters are chemical messengers that transmit signals across synapses, the junctions between neurons. They travel very short distances and enable communication between neurons.
Some neurotransmitters can act as hormones when released into the bloodstream. These chemical signals can travel long distances to affect distant tissues and organs.
Recent discoveries suggest that neurons working together create electric fields, which in turn can influence the behavior of the neurons that created them. This creates a feedback loop of neuronal activity and electric field interactions.
Some scientists hypothesize that quantum mechanical processes might play a role in brain function. While still controversial, this idea suggests that quantum effects could contribute to cognitive processes.