Detecting traces of consciousness in the process of intending to act

An intention to act has different onsets when it is measured in different ways. When participants provide a self-initiated report on the onset of their awareness of intending to act, the report occurs around 150 ms prior to action. However, when the same participants are repeatedly asked about their awareness of intending at different points in time, the onset of intending is found up to 2 s prior to action. This ‘probed’ awareness has its onset around the same time as the brain starts preparing the act, as measured using EEG. First of all, this undermines straightforward interpretations about the temporal relation between unconscious brain states and conscious intentions and actions. Secondly, we suggest that these results present a problem for the view that intentions are mental states occurring at a single point in time. Instead, we suggest the results to support the interpretation of an intention to act as a multistage process developing over time. This process of intending seems to develop during the process of acting, leaving reportable traces in consciousness at certain points along the road. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00221-016-4600-1) contains supplementary material, which is available to authorized users.