STP profile | 10–20 Hz slope | 20–30 Hz slope | 30–40 Hz slope | Overall (R^{2}) | 10–20 vs 20–30 | 20–30 vs 30–40 | 10–20 vs 30–40 |
---|---|---|---|---|---|---|---|

No plasticity | 0.59 ± 0.08 | 0.54 ± 0.05 | 0.48 ± 0.06 | 0.55 (0.998) | 0.935 | 0.266 | 0.420 |

□ | 0.35 ± 0.05 | 0.24 ± 0.03 | 0.20 ± 0.02 | 0.26 (0.983) | 0.148 | 0.270 | 0.050* |

◊ | 0.91 ± 0.11 | 0.56 ± 0.08 | 0.33 ± 0.04 | 0.60 (0.955) | 0.022* | 0.049* | 0.003* |

∇ | 1.15 ± 0.15 | 0.71 ± 0.07 | 0.48 ± 0.05 | 0.77 (0.964) | 0.080 | 0.045* | 0.016* |

The square, diamond, and triangle are explained in Figure 2.

The slopes of the input–output function of each STP profile shown in Figure 5 are given for each segment of the range in input rates (10–20, 20–30, and 30–40 Hz) as mean ± SEM from the measurements made in each neuron (

*n*= 6). A slope of 1 indicates that output spiking increased by 10 Hz for an increase of 10 Hz in input rate. In addition, the slopes of the linear regression through the mean data points for each STP profile are given along with the*R*^{2}value of the linear regression. To examine the nonlinearity of each STP profile, the slopes from each portion of the plot of each STP parameter were compared using a*t*test, and the resulting*p*values are given in the table.*Asterisks*denote comparisons that are significantly different at a level of α = 0.05, indicating nonlinearity in the input–output function.