Visual cortical contributions to emotional imagery

Previous work has shown that mental imagery activates the visual cortex, including the primary visual cortex. Here, we examined the role of the visual cortex in representing the motivational significance of imagined events by recording fMRI data in an emotional imagery paradigm. In each trial, the participant began by silently reading a text varying in affective content (pleasant, neutral, or unpleasant) and then proceeded to imagine their active involvement in the described event continuously until the end of the trial. Applying both univariate and multivariate analysis methods to the fMRI data, we found that (1) the univariate analysis did not demonstrate valence-dependent activation in the visual cortex, which is consistent with findings from previous studies and (2) the MVPA analysis revealed above-chance decoding accuracy for pleasant vs neutral, unpleasant vs neutral, and pleasant vs unpleasant imagery in the entire visual hierarchy including the primary visual cortex. These results show that the visual cortex contributes to the representation of motivational significance of imagined events and multivariate analysis is essential in uncovering the valence-specific neural patterns in the visual cortex.