Computational Modeling of AÃ\x9f Fiber Wind-up

Wind-up, a condition related to chronic pain, is described traditionally as a frequency dependent increase in the excitability of sensory spinal cord neurons, evoked by electrical stimulation of small pain fibers. In this paper, we introduce a computational model on wind-up of large (Abeta) fibers, considering three major mechanisms of wind-up: 1) a feedforward mechanism causing Ca²⁺ entry, 2) a positive feedback, causing more Ca²⁺ entry, and 3) a feedforward due to sprouting of Abeta fibers towards the small pain fibers. Our model proposes three different ways for reducing wind-up and shows the most important way to treat the pain