Figure 2.

Three examples of DLPFC spatial-bias neurons and one non-bias neuron. Raster plots (top; ranked by increasing trial number for trials with subsequent leftward and rightward eye movements separately), spike-density function plots (mean ± SEM; middle), and logistic-regression best-fits (bottom) to the data of 4 DLPFC neurons (Panels A and D from Animal D, B and C from J). Cue onset is at 0 s, so depicted is spiking activity from the last half-second of the inter-trial interval as well as from the 1 s fore period. The data is taken from all the undetermined (UNDET) trials of each neuron, because bias neurons were selected using only UNDET trials. Panels (A–C) depict spatial bias neurons, while panel (D) is a non-bias neuron. The number of trials associated with each data point in the logistic regression is designated by the diameter of the symbol. (See Figure S2A for ROC and choice-probability analyses of these neurons.).