The sustained attention to response task (SART) is a popular measure in the psychology and neuroscience of attention. The underlying psychological cause for errors, in particular errors of commission, in the SART is actively disputed. Some researchers have suggested task-disengagement due to mind-wandering or mindlessness, and others have proposed strategic choices. In this study we explored an alternative perspective based on Signal Detection Theory, in which the high rate of commission errors in the SART reflects simply a shift in response bias (criterion) due to the high prevalence of Go-stimuli. We randomly assigned 406 participants to one of ten Go-stimuli prevalence rates (50%, 64%, 74%, 78%, 82%, 86%, 90%, 94%, 98% and 100%). As Go-stimuli prevalence increased reaction times to both Go and No–Go stimuli decreased, omission errors decreased and commission errors increased. These all were predicted from a hypothesized bias shift, but the findings were not compatible with some alternative theories of SART performance. These findings may have implications for similar tasks.

持续关注反应任务 (SART) 是注意力心理学和神经科学中的一种流行测量方法。SART 中错误（尤其是佣金错误）的潜在心理原因存在争议。一些研究人员建议由于走神或无意识而导致任务脱离，而其他人则提出了战略选择。在这项研究中，我们探索了基于信号检测理论的另一种观点，其中 SART 中的高佣金错误率仅反映了由于围棋刺激的高流行而导致的响应偏差（标准）的转变。我们将 406 名参与者随机分配到 10 个 Go 刺激流行率（50%、64%、74%、78%、82%、86%、90%、94%、98% 和 100%）之一。随着 Go 刺激普遍性增加，对 Go 和 No–Go 刺激的反应时间减少，遗漏错误减少，佣金错误增加。这些都是从假设的偏差转移中预测出来的，但这些发现与 SART 性能的一些替代理论不相容。这些发现可能对类似任务有影响。