Consistency of extracellular and intracellular classification of simple and complex cell
Using a rectification model and an experimentally measured distribution of the extracellular modulation ratio (F1/F0), we investigate the consistency between extracellular and intracellular modulation metrics for classifying cells in primary visual cortex (V1). We first demonstrate that the shape of the distribution of the intracellular metric χ is sensitive to the specific form of the bimodality observed in F1/F0. When the proper mapping between F1/F0 and χ is applied to the experimentally measured F1/F0 data, χ is weakly bimodal. We then use a two-class mixture model to estimate physiological response parameters given the F1/F0 distribution. We show, once again, that a weak bimodality is present in χ. Finally, using the estimated parameters for the two cell clases, we show that simple and complex cell class assignment in F1/F0 is more-or-less preserved in a heavy-tailed f1/f0 distribution, with complex cells being in the core of the f1/f0 distribution and simple cells in the tail (misclassification error in f1/f0 = 19%). Class assignment in f1/f0 is likewise consistent (misclassification error in F1/F0 = 15%). Our results provide computational support for the conclusion that extracellular and intracellular metrics are relatively consistent measures for classifying cells in V1 as either simple or complex.