Effect of cholineacetyltransferase activity and choline recycle ratio on diffusion-reaction modeling, bifurcation and chaotic behavior of acetylcholine neurocycle and their relation to Alzheimer's and Parkinson's diseases

► The effects of ChAT activity and choline recycle ratio are investigated. ► The dynamics of ACh system is monitored through the two-compartment model. ► ACh concentration in both model compartments increases as ChAT activity increases. ► Choline uptake represents the key role for providing choline for ACh processes. ► Bifurcation analysis is achieved to highlight the characteristics of ACh system.