Dynamical Systems in Neuroscience:

334 Simple ModelsFigure 8.34: Classification of hippocampal CA1 pyramidal neurons. A-E, in vitrorecordings from five different pyramidal neurons arranged according to a gradient ofincreasing propensity to burst. The neurons were stimulated with current pulses of 200ms duration and amplitude 50 pA and 100 pA (a), or brief (3-5 ms) superthresholdpulses (b). Non-burster (NB) neuron fires tonic spikes in response to long pulses anda single spike in response to brief pulses. High-threshold burster (HTB) fires burstsonly in response to strong long pulses, and single spikes in response to weak or briefpulses. Grade I low-threshold burster (LTB I) generates bursts in response to longpulses of current, but single spikes in response to brief pulses. Grade II LTB (LTB II)fires bursts in response to both long (a) and brief (b) current pulses. Grade III LTB(LTB III), in addition to firing bursts in response to long and brief pulses of current(not shown) also fires spontaneous rhythmic bursts, shown in contracted and expandedtime scales (reproduced from Su et al. (2001) with permission).