Figure 6.

Illustration of the one-choice diffusion decision model for the PVT. After presentation of a stimulus and subsequent stimulus encoding, a decision process takes place during which evidence is accumulated through neuronal processing resembling a random walk with a certain drift rate. When the accumulated evidence reaches an evidence criterion, the decision process stops and a response is made. While performing the PVT, the evidence criterion must be set in advance of the stimulus onset and maintained throughout the RSI, which in the face of sleep deprivation may require sustained effort. Figure adapted from Ratcliff and Van Dongen [75].