Show different outcomes following drug administration, and activate diverse, but overlapping brain regions. It has been argued that the two tasks may index different aspects of inhibition–e.g., inhibition of reified/wellentrenched processes in the Stroop versus inhibition of recently learned associations in the stop-signal. Some have even argued that, other than the cancellation of motor responses, most ‘inhibitory’ phenomena may be explained by “inhibition-free model”. For Compound Library example, it is possible that Stroop interference may be accounted for by proactive mechanisms such as sustained activation of goal or task representations. More recent models of inhibitory control tend to conceptualize performance on tasks such as the Stroop and stop-signal as a result of both proactive/early-selection mechanisms and reactive/late-correction mechanisms, with the emphasis on proactive/reactive control amenable to variations in both person and situational factors. Empirical findings of a weak relationship between the two tasks’ measures may thus reflect the engagement of different constructs or different combinations of similar processes. On the other hand, low correlations may also arise from measurement issues. The literature sees a mix of accuracy and reaction time scores from different task variants, often computed in different ways across studies. Inhibitory control in the Stroop task is commonly indexed by Stroop interference reaction time, amongst other measures such as accuracy rates and commission/intrusion errors. Stroop interference RT is calculated equally often as the mean latency difference between incongruent and neutral conditions, and between incongruent and congruent conditions. The neutral control is sometimes preferred over the congruent condition which can be confounded by individual differences in facilitation effects. On the other hand, the congruent condition serves as a closer control for the incongruent condition in terms of stimulus-response dimensional overlap. Some studies have examined interference RT in terms of delta-plots derived by rank-ordering each participant’s RTs for each condition and then plotting the mean interference RT by quantiles. A weak or slow inhibitory process is hypothesized to benefit Stroop performance most at slower RTs, giving an accurate-trials RT distribution a negative skew, and a steeper interference delta slope. Though not conventionally used, the recent years have also seen Stroop interference begin to be examined in terms of inverse efficiency –an adjusted RT measure derived by dividing RT by its corresponding percentage accuracy–in a small handful of studies. Conventional RT measures are typically based on accurate trials only. The IE score adjusts RT performance for sacrifices in accuracy that might have been made in favor of speed. A mean RT achieved with high accuracy will have a smaller IE than the same RT achieved at the cost of more errors. The hybrid IE score may be especially useful when there are individual or developmental differences in speed-accuracy trade-offs, in which case accuracy and RT data can show different patterns of results.