Information is relayed within the nervous system by neurons which send out electrical impulses through the stimulation by heat, pressure, light and other chemical substances. During these actions, the neurons undergo a potential process which is a difference in electrical charges.The two charges occur in two phases which are the resting potential and/or the action potential. For this to take effect, neural threshold (a point where no stimulation occurs) must be reached or the occurrence of depolarization where change in a cell potential is experienced. With this in place, there is occurrence of resting to action potential.The action potential is accompanied by a short period of refractory period which affects neuron stimulation and lasts for a short period which is then followed by the relative refractory period which requires stronger stimulation to trigger the action potential before the neuron returns to resting state.
Through neurotransmitters, information is transmitted from the axon of the first neuron to the dendrites which happen as a result of action potential. This happens through the process of synaptic transmission. When neurotransmitter and receptor molecules combine, a change (postsynaptic potential, PSP) occurs in the postsynaptic cell membrane. This allow for the movement of ions in and out of the postsynaptic neuron. This movements increase or decrease probable effects of the occurrence of neural impulses in the postsynaptic neuron.
Postsynaptic potential occurs as excitatory postsynaptic potential (EPSP) and Inhibitory postsynaptic potential (IPSP). (EPSPs) increase and (ISPS) decrease the possibilities that the postsynaptic neuron will stimulate a neural impulse. This rate at which a neuron is stimulated is dependant on the relative number of EPSPs and IPSPs.