State-dependent LTD in the dorsal striatum. A, State-dependent LTD induction protocol. The membrane holding potential (hp) was varied between -70 and -50 mV every 0.5 s for a total of 5 min. Steps to -50 mV were paired with 10 presynaptic stimuli at 25 Hz (stim). Medium spiny neuron responses to this stimulus protocol are shown below for an individual experiment. Capacitance transients have been truncated, and stimulus artifacts have been blanked for clarity. B, EPSC amplitude (top graph; filled circles) is plotted for an individual experiment. The dotted line above the graph represents the time of LTD induction. The PPR (bottom graph; open circles) is shown below. Ca, Average EPSC trace from 0-10 min (thick trace) overlaid with average EPSC trace from 30-40 min (thin trace) from the experiment shown in A and B. Cb, Average EPSC trace from 0-10 min (thick trace) overlaid with the scaled average EPSC trace from 30-40 min (thin trace). Each point represents an average of three EPSCs. Experiments were performed at 30-32°C.