A model account of the neural and behavioral observations in Monkey A.

<p><b>A.</b> Empirically observed behavioral data from monkey A (left) and simulated behavioral results (right) of the competing accumulator model described in the text. Four colors indicate the four reward conditions: HH (red), LL (blue), HL (black; LH (green). <b>B.</b> Empirically observed physiological data from monkey A (left) and simulated physiological results (right) for the imbalanced reward conditions. Solid lines indicated trials ending in T1 choices; dashed lines illustrate trials ending in T2 choices. Color code is the same as in the top panels. <b>C.</b> Empirically observed physiological data from monkey A (left) and simulated physiological results (right) for the balanced reward conditions. Solid and dashed lines, and the color code, are the same as in the preceding panels. Parameter values used in the reported fits are as follows: <i>b</i> = 10; <i>a</i> = 0.5; <i>σ_b</i> = 14; <i>σ_w</i> = 1, θ = 22. Values are in units of seconds and Hertz.