How does the CNS know weather a stimulus is strong or weak?

Answer 1

Nerves do not fire at varying intensities; for example, neurons won't fire at a stronger intensity if you're hit with a Baseball in comparison to a marble. The difference between the two stimuli is the number of firing neurons. After being hit with a baseball, the affected neurons will fire more frequently than if hit with a marble.

Answer 2

The central nervous system (CNS) determines the strength of a stimulus based on the frequency and number of action potentials generated by sensory neurons in response to the stimulus. Stronger stimuli result in a higher frequency and more action potentials being sent to the CNS, signaling a stronger stimulus. This information is then processed and interpreted by the CNS to generate an appropriate response.