Illustration of the model and its basic properties.

<p>(<b>A</b>) Schematic of the single compartment model used in this study. The various ligand- and voltage-gated channels used in the model are depicted as arrows, and the transmembrane voltage Vm was recorded in response to Poisson-modulated excitatory synaptic inputs or to pulse current injections. (<b>B</b>) Voltage traces (for 1 s) depicting neuronal firing for Poisson-distributed synaptic stimulation at various stimulus frequencies (SF). (<b>C</b>) Plot showing firing frequency (FF) as a function of SF. Data represented as mean ± SEM for 100 trials of Poisson-distributed synaptic stimulation at each SF. (<b>D</b>) Functional form of the plasticity-regulating (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055590#pone.0055590.e077" target="_blank">Equation 14</a>) plotted as a function of intracellular calcium levels. (<b>E</b>) Synaptic plasticity was induced by stimulating the colocalized NMDAR-AMPAR synapses with 900 pulses of various induction frequencies (<i>f</i>_i) spanning a range of 0.5–25 Hz. Depicted are pulses for five different frequencies for a period of 1 s. As the number of pulses was set at 900 irrespective of the induction frequencies, induction of plasticity through a lower frequency pulse will run for a longer time compared to induction through a higher frequency pulse. (<b>F</b>) BCM-like synaptic weight (<i>w</i>) change induced through various induction frequencies. Arrow indicates the initiation of spikes during the induction protocol.