A key goal in the study of decision making is determining how neural networks involved in perception and motor planning interact to generate a given choice, but this is complicated due to the internal trade-off between speed and accuracy, which confounds their individual contributions. Urgent decisions, however, are special: they may range between random and fully informed, depending on the amount of processing time (or stimulus viewing time) available in each trial, but regardless, movement preparation always starts early on. As a consequence, under time pressure it is possible to produce a psychophysical curve that characterizes perceptual performance independently of reaction time, and this, in turn, makes it possible to pinpoint how perceptual information (which requires sensory input) modulates motor planning (which does not) to guide a choice. Here we review experiments in which, on the basis of this approach, the origin of the speed-accuracy trade-off becomes particularly transparent. Psychophysical, neurophysiological, and modeling results in the “compelled-saccade” task indicate that, during urgent decision making, perceptual information—if and whenever it becomes available—accelerates or decelerates competing motor plans that are already ongoing. This interaction affects both the reaction time and the probability of success in any given trial. In two experiments with reward asymmetries, we find that speed and accuracy can be traded in different amounts and for different reasons, depending on how the particular task contingencies affect specific neural mechanisms related to perception and motor planning. Therefore, from the vantage point of urgent decisions, the speed-accuracy trade-off is not a unique phenomenon tied to a single underlying mechanism, but rather a typical outcome of many possible combinations of internal adjustments within sensory-motor neural circuits.

Highlights d Urgent choice tasks reveal temporal relationships between neural firing and behavior d FEF visual neurons select targets only for some visually informed saccadic choices d FEF visual target selection reflects feature saliency rather than feature relevance d Isolating the pure visual signal is critical for interpreting FEF activity in general

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The purpose of this study was to use established measures of attentional reserve capacity to test for the existence of tactile-specific resources in the context of Wickens ' (1984, 2002) Multiple Resource Theory. Participants performed a primary counting task in the tactile modality and were presented with a concurrent secondary attention task in the visual, auditory, and tactile modalities. The data indicate a significant difference in performance based on whether the dual-task conditions were performed crossmodally or unimodally, in terms of percent correct and response time to target stimuli. Specifically, participants performed significantly worse in tactile-tactile dual-task conditions, suggesting performance was degraded as a function of resource depletion. Furthermore, participants rated the unimodal dual-task conditions as significantly harder, using a subjective workload rating, than either of the dual-task crossmodal conditions, or the single task condition. The results suggest that task interference was a function of resource limitation rather than structural interference, providing direct empirical evidence supporting the inclusion of tactile resources in Wickens' Multiple Resource Theory.