A single neuron example of the enhancing effects of PF-3628 on delay-related firing. A: Iontophoresis of PF-3628@25nA significantly enhanced delay-related firing for the neuron’s preferred direction, not for the non-preferred direction. Activity was reduced to control levels after drug application was terminated during the recovery condition (third panel; control vs recovery: p>0.05, one-way ANOVA). Rasters and histograms for preferred direction and non-preferred direction during control condition and PF-3628 application condition and recovery are shown. B: Statistical analysis of the neuronal firing rates across the delay epoch for the Delay cell shown above, during control, PF-3628, and recovery conditions. C: Spatial tuning changes for this Delay cell during control, PF-3628, and recovery conditions.