What Is All-Or-None Law?

The all-or-none law is a principle that proposes the strength of a response with respect to a muscle fiber or nerve cell is not dependent on the strength of the stimulus. Essentially, if a stimulus reaches a certain threshold, the muscle fiber or nerve will fire. Part of the transmission process that occurs with this firing is known as an action potential. During the action potential, a part of the neural membrane opens up to allow negatively charged ions out, and positively charged ions into the cell. However, if the stimulus doesn’t reach the required threshold, there won't be a response. Simply put, either no response will occur, or a full one will. There is no level between the two. During firing, the action potential process causes an increase in the positive charge of the …show more content…
Once the charge reaches +40 mv, the impulse is broadcast down the nerve fiber, and carried down the nerve through a series of action potentials. All of this requires that the threshold be met for the firing to occur in the first place. If it is, the electrical signal will be sent down the axon. Actions potentials either happen or they don’t, which is the principle of the all-or-none law. This mechanism ensures the neurons fire at full strength, with a consistent intensity that allows the signal to be carried down the fiber and transferred to the next cell without