End-stopping in the visual cortex: excitation or inhibition?

In the visual cortex some neurons respond more strongly to short stimuli than to long ones. This is referred to as "end-stopping" and has been generally attributed to inhibition. The role of inhibition, however, has been difficult to demonstrate. Moreover, modeling has shown that end-stopping can be created solely from excitation. The roles of excitation and inhibition were investigated using intracellular recordings (Anderson et al., 2001, J. Neurosci. 21: 2104-2112). The results of that study were interpreted in favor of inhibition. The present report re-examines these results and finds that they may be in good, perhaps even better, agreement with an excitation model of end-stopping.