Issues

Cover picture: Four bifurcation diagrams and corresponding time simulations of bursting made with a Chay–Keizer model of a cell. In the top of each pair of panels, the solid black line represents stable states of V_m as a function of (clamped) Ca, the dashed and dotted lines represent unstable equilibria and unstable oscillations, and the blue lines represent burst trajectories. The bottom of each pair of panels shows the corresponding time-dependent changes in V_m with Ca free to vary. Upper left: square wave without spikes; upper right: β cell–like bursting; lower left: pituitary-like bursting; lower right: bursting without bistability but with two slow variables, as in the R15 neuron of Aplysia (see commentary by Sherman, 13–19).