People create meaning frameworks to make sense of the world. Moderate political or religious attitudes require individual meaning frameworks to be flexible and changeable, whereas extreme attitudes are based on fortified, rigid, and hard-to-change meaning frameworks. Research has shown that individuals with extreme (vs. moderate) political or religious attitudes react to expectancy violations with reduced neurophysiological markers of arousal. To test the assumption that these reduced immediate reactions are due to top-down attentional processes, we recorded electrophysiological activity during the presentation of normal and anomalous playing cards (N = 79). The presence of anomalous playing cards in the stimulus set boosted prestimulus alpha power, an index of top-down attentional processing, among individuals with extreme, but not moderate political attitudes. On the other hand, anomalous playing cards increased the late positive potential (LPP), a marker of allocation of attentional resources, among moderates, but not extremists. The findings support the assumptions that extremists engage in more top-down attentional processing, presumably to prevent their fortified meaning systems to be modified through novel experiences. This might partly explain why extremists also attend to perceptual anomalies less than moderates.