What a stimulus predicts, not what it depicts, determines striatal reward signals

Free viewing of emotional pictures activates motivational circuits as a function of arousal and valence, yet, because no real outcomes are delivered, anticipatory wanting and consummatory liking cannot be dissociated. Gustatory neuroimaging paradigms deliver actual rewards but use impoverished, affectively neutral cues that do not engage natural selective attention. We bridged these paradigms by presenting emotional images alongside food photographs that either predicted juice delivery (Food+) or did not (Food-), all within a single fMRI session. On each Food+ trial, participants indicated in real time whether they wanted the juice, enabling a within-subject dissociation of anticipatory from consummatory signals. Nucleus accumbens showed a large and selective response to Food+ cues that exceeded activation to both pleasant (erotica) and unpleasant (mutilation) high-arousal images, establishing that mesolimbic engagement tracked outcome prediction rather than emotional arousal, affective valence, or visual content. A temporal dissociation further revealed that nucleus accumbens carried the dominant anticipatory signal during the cue period, while ventromedial prefrontal cortex carried the dominant outcome-period signal at juice delivery, a pattern consistent with the wanting and liking distinction. Representational similarity analysis confirmed that outcome prediction, rather than emotional arousal, affective valence, or visual category, was the dominant organizing principle of the multivariate neural response across the full region-of-interest network. Together, these findings show that whether a visual stimulus engages reward circuitry depends less on what it depicts than on what it predicts, and provide a framework for studying individual differences in appetitive motivation and cue-induced eating.