This is the readme for the models associated with the paper: Rahul Gupta, Melissa Reneaux, Karmeshu (2016) Role of Macromolecular Crowding and Geometrical Irregularity at Central Excitatory Synapses in Shaping Synaptic Transmission. PLOS ONE MATLAB Scripts for the Numerical Simulation of Glutamate Diffusion, Stochastic AMPA Receptor Activation and EPSC generation This code was contributed by Rahul Gupta. There are three folders: (1) Glutamate_diffusion. It contains scripts for two seperate situations of glutamate diffusion viz. (a) Standard diffusion with zero sigma_Dglut and (b) Diffusion with non-zero sigma_Dglut. Both these scripts perform simulation of the Brownian dynamics of glutamate diffusion within the cleft space under the prescribed absorbing and reflecting boundary conditions. (2) Stochastic_AMPAR_activation. It contains scripts for the stochastic activation of AMPA receptors located in the PSD in response to the temporal profile of the local glutamate concentration obtained from the numerical simulation of glutamate diffusion. The script "AMPAR_activation_GillspiAlgorithm.m" perform the stochastic activation of AMPA receptors using modified Gillespie algorithm proposed by Skaugen and Walloe (1979). During simulation, it repeatedly calls another script "AMPAR_activation_MNscheme.m", which contains kinetic parameters of transition among the various states of AMPA receptor under the Milstein-Nicoll scheme. (3) EPSC_generation. It contains a single script to compute the resultant profile of EPSC generated due to stochastic AMPA receptor activation.