Neural subspace reorganization reflects value-based decision-making

Value-based decision-making requires maintaining and comparing multiple options to guide behavior. While the neural circuits supporting these decisions are increasingly understood, how decisions reshape option representations remains unclear. We recorded from lateral prefrontal cortex (LPFC) while non-human primates held two sequentially presented option-value pairs in working memory and selected the higher value option. We found that, once a decision could be made, representations of the chosen and unchosen options rotated into orthogonal neural subspaces, while the chosen representation expanded. Before the decision, representations were organized by presentation order. After the decision, the chosen option, regardless of presentation order, was transformed into a common subspace aligned with the prescribed action. These findings suggest that value-based decisions reorganize LPFC population activity to selectively represent the chosen option, enabling efficient downstream readout for action selection.