Detecting own errors is a crucial precondition for adaptive behavior. It has long been known that the human brain is equipped with an error monitoring system that registers errors which then leads to adjustments of attention and behavior. However, the mechanisms behind these adjustments and their functional significance are still under debate. Particularly the role of post-error adjustments of attention is rather unclear. Whereas traditional accounts assume that errors lead to adaptive adjustments of attention that improve future performance, others suggested that errors elicit a maladaptive orienting response that even increases the probability of further errors. A recently proposed theory integrates these findings by assuming that adaptive and maladaptive adjustments occur at different time points after the error, but a direct test of this idea is still pending. In the present project, we will utilize steady-state visual evoked potentials (SSVEPs) in the electroencephalogram to directly measure attentional adjustments after errors. This allows us to address several open questions: First, by tracking the time course of post-error attentional adjustments, we will ask whether adaptive and maladaptive adjustments occur at different time points after an error. Second, by manipulating temporal aspects of stimulus presentation, we will test the idea that maladaptive attentional adjustments are a consequence of discrete laboratory tasks to which our brain is not optimally adapted. Third, we will investigate whether attentional adjustments are reactive or proactive by asking whether they take previous or future task demands into account. And finally, we will determine whether attentional adjustments depend on the source of an error and hence occur particularly when errors are due to failures of selective attention. In all studies, we will further investigate how attentional adjustments relate to component processes of error monitoring by correlating changes in the SSVEP with error-related brain activity in event-related potentials (Ne/ERN, Pe) and oscillations (theta) using single-trial analyses. The results of this project will advance our knowledge about the neural and cognitive mechanisms underlying post-error adjustments of attention and behavior.