Goal-directed action selection relies on conjunctive representations that bind goals, actions and expected sensory outcomes

Goal-directed actions are performed to obtain specific sensory outcomes. However, theories of action control diverge on whether anticipated outcomes are only consequences of motor command specification or serve as instrumental determinants of action selection. Here, we directly tested whether predicted sensory outcomes are integrated into the neural processes underlying the selection of goal-directed actions. Participants learned novel action-outcome contingencies and selected actions to generate specific sensory outcomes, while their brain activity was recorded using EEG. Combining time-resolved multivariate decoding with representational similarity analysis, we tracked both feature-specific and conjunctive neural representations over time. We found that the strength of high-dimensional conjunctive representations including anticipated sensory outcomes predicted trial-to-trial reaction times, even after accounting for individual task features. These results provide neural evidence that predicted sensory outcomes are not downstream consequences, but core determinants of action selection, supporting the view that actions are selected to control expected sensory input.