Figure 5.

Suppressive effect of pulse trains on neurons from young adult and aged animals. A, Probability of each pulse train from the pulse matrix to suppress neurons from young adult animals. Each square in the surface plot depicts the percentage of cells the pulse train of the indicated pulse and pause duration was suppressive to. Percentage is color coded. Discharges of neurons from young adult animals were mostly suppressed by pulse trains of short pulse and short pause durations. B, Probability of each pulse train from the pulse matrix to suppress neurons from aged animals. Similar to young adult animals, discharges of neurons from aged animals were most effectively suppressed by pulse trains of short pulse and short pause durations C, Difference between probability distributions of pulse trains suppressing neurons from young adult and from aged animals, respectively. Pulse trains of long pulse durations independent of pause duration and pulse trains of short pulse and pause duration were more likely to suppress discharges in young adult animals than in aged animals. Pulse trains of short pulse duration and long pause duration were more likely to suppress discharges in aged animals (Wilcoxon's rank sum test, p = 0.04).