The late positive potential (LPP) is a sustained positive deflection in the event-related potential that is larger following the presentation of emotional compared to neutral visual stimuli. Recent studies have indicated that the magnitude of the LPP is sensitive to emotion regulation strategies such as reappraisal, which involves generating an alternate interpretation of emotional stimuli so that they are less negative. It is unclear, however, whether reappraisal-related reductions in the LPP reflect reduced emotional processing or increased cognitive demands following reappraisal instructions. In the present study, we sought to examine whether a more or less negative description preceding the presentation of unpleasant images would similarly modulate the LPP. The LPP was recorded from 26 subjects as they viewed unpleasant and neutral International Affective Picture System images. All participants heard a brief description of the upcoming picture; prior to unpleasant images, this description was either more neutral or more negative. Following the more neutral description, the magnitude of the LPP, unpleasant ratings, and arousal ratings were all reliably reduced. These results indicate that changes in narrative are sufficient to modulate the electrocortical response to the initial viewing of emotional pictures, and are discussed in terms of recent studies on reappraisal and emotion regulation.