NBCE Exam 2025 – 400 Free Practice Questions to Pass the National Board of Chiropractic Examiners

The correct answer, facilitation, refers to the process whereby an increase in afferent stimuli lowers the threshold for synaptic transmission, making it easier for the postsynaptic neuron to reach the threshold for firing an action potential. In this context, facilitation enhances the responsiveness of neurons due to the interaction of incoming signals. It essentially means that with increased stimulation, the neuron is primed and more likely to respond.

Understanding facilitation is crucial in both physiological and clinical settings because it explains how increased sensory input can influence neuronal activity, potentially leading to heightened awareness of pain or increased reflex responses. This concept is significant in chiropractic practice, where the modulation of neuronal activity plays a crucial role in treatment strategies for pain management and neuromusculoskeletal health.

The other options present different concepts. Inhibition refers to the decrease in neuronal excitability and reduced likelihood of firing due to various factors. Normalization often refers to processes that aim to return systems to a baseline state, while desensitization involves a reduction in response to a constant stimulus over time. Each of these plays a role in different contexts but does not pertain directly to making it easier for synaptic thresholds to be reached due to increased afferent stimuli.