This study investigated the role of expertise and personality in reactions to challenges in contemporary paintings, here operationalized as violations in syntax and semantics. Thirty-eight expert and 56 naïve art viewers appraised 20 paintings (divided into four groups, i.e. no violation, only syntactic or semantic violation, and both semantic-syntactic violations) on scales of valence, activation, sense-making, understanding and appreciation. Viewing time was also recorded and participants filled in questionnaires measuring the Big Five model of personality and Need for Closure. Separate mixed linear models were fit for each outcome variable (rating scales and viewing time) with the type of violations, expertise and personality measures as predictors. It was found that syntactically violated paintings predicted best viewers' reaction to art. Such paintings were viewed longer and evoked reactions modulated by individual differences and expertise. Expertise was found to be a positive predictor of understanding and appreciation of paintings with syntactic violations. Conversely, need for closure turned out to be a negative predictor of sense-making, understanding, and liking those types of art. Similarly, people high in neuroticism liked syntactically violated artworks less. Only openness to experience turned out to be a positive predictor of sense-making and activation in all types of stimuli. The results are discussed in terms of elevated challenge, which syntactically violated paintings present, and different strategies of viewers to cope with this.