Figure 4. Effects of 0.375 mM (1.5 minimum alveolar concentration) halothane on spontaneous action potential firing of a neocortical neuron. (A) Spike rates while halothane was applied. Action potentials were binned at 100 ms-intervals. (B, C) The spike rates and discharge patterns of the same cell before, during, and after halothane administration. Mean spike rates were 7.87 Hz (control), 1.56 Hz (0.375 mM halothane), and 7.51 Hz (wash). The temperature was 22 - 24 [degree sign]C.