In hippocampal CA1 pyramidal neurons, the distal apical tuft receives inputs from entorhinal cortex via the temporoammonic (TA) pathway. Though electrotonically distant from the cell soma, TA inputs have been shown to influence hippocampal place cell firing. Using a morphologically accurate compartmental model we were able to replicate results of previously reported voltage sensitive dye imaging studies (Ang, Carlson, & Coulter, SFN, 853.1, 2004) showing that local circuit activity shapes the effect of TA inputs into area CA1. Specifically we were able to show following three features: 1) Burst stimulation in the stratum lacunosum moleculare evoked EPSPs spatially restricted to the TA pathway. 2) Removal of GABAA inhibition significantly increased TA throughput to the cell soma. 3) When burst stimulation in the stratum lacunosum moleculare is preceded (40 ms) by excitatory input to Shaffer collateral afferents, TA throughput to the cell soma is significantly increased. In the model, the TA input triggers d...