Pictorial vs. linguistic negation: Investigating negation in imperatives across different symbol domains.

The processing of negation is typically regarded as one of the most demanding cognitive processes as it often involves the reversal of input information. As negation is also regarded as a core linguistic process, to date, investigations of negation have typically been linguistic in nature. However, negation is a standard operator also within non-linguistic domains. For example, traffic signs often use negation to indicate a prohibition of specific actions (e.g., no left turn). In the current study, we investigate whether processing difficulties that are typically reported within the linguistic domain generalize to pictorial negation. Across two experiments, linguistic negation and pictorial negation were directly compared to their affirmative counterparts. In line with the literature, the results show that there is a general processing benefit for pictorial input. Most interestingly, the core process of negation also benefits from the pictorial input. Specifically, the processing difficulty in pictorial negation compared to affirmation is less pronounced than within the linguistic domain, especially concerning error rates. In the current experiments, pictorial negation did not result in increased error rates compared to the affirmative condition. Overall, the current results suggest that negation in pictorial conditions also results in a slowing of information processing. However, the use of pictorial negation can ease processing difficulty over linguistic negation.