Non-Centered Spike-Triggered Covariance Analysis Reveals Neurotrophin-3 as a Developmental Regulator of Receptive Field Properties of ON-OFF Retinal Ganglion Cells
Figure 4
Spiking in response to both positive and negative contrasts (ON-OFF behavior) produces bimodal distributions and symmetric nonlinearities, while ON or OFF cells produce unimodal distributions and asymmetric nonlinearities.
(A) Scatter plot of the STC-NC bias against the p value for the null hypothesis of a unimodal distribution. Bimodality was measured using the Hartigan and Hartigan Dip Test. Red lines at −0.6 and 0.6 show the cutoffs for ON and OFF classification. (B–C) The majority of ON and OFF cells were unimodal (e.g., B#1 and B#3) with highly asymmetric static nonlinearities, however, a few demonstrated highly unbalanced bimodality (C#4). Most ON-OFF cells were bimodal with a symmetric static nonlinearity (B#2), though some possessed less symmetric nonlinearities and were not bimodal (C#5).