Figure 1. Examples of timing and temporal cognition tasks.

A. In an explicit timing task, a mouse learns the reward delay associated with each cue and produces anticipatory licking during the appropriate cue-specific interval. B. In an implicit timing task each trial may be initiated by a cue (green or red), and humans are asked to respond to a white square. In valid trials each cue is associated with a short or long delay, but in a small number of invalid trials the relationship is reversed. Reaction times are faster in the valid trials even though the task simply requires responding to the target. C. Temporal discounting tasks require animals to select between a smaller-sooner reward versus a larger-later reward. Whereas the delay to the small reward remains at 10 s, typically the delays to the larger reward increase in trial blocks from 10s, 20s, 40s, up to 60s. D. Temporal wagering tasks require animals to wait for variable delay reward following discrimination (i.e., categorization) of an uncertain stimulus. Longer wait times are generally associated with certainty, a proxy for confidence. Importantly, animals can abort the trial at any time during the delay, an outcome generally associated with uncertainty. E. Temporal distribution tasks require animals to discriminate between options with different distributions of reward delays. In this example, animals initiate a trial (central white square), then choose between stimuli associated with the same mean wait time (μ=10s) but different standard deviation of delays (σ either 1s or 4s).