The present study aimed to test the hypothesis that facilitatory effects of a regular rhythmic prime on grammaticality judgement tasks are due to the priming of abstract hierarchical structure. If hierarchical structure is coded in an abstract format, one would expect to find selective facilitatory effects of a rhythmically regular prime not only in linguistic tasks, but also in non-linguistic tasks that involve internal structure building. Sixty-five L1 French speakers listened to silent, rhythmically regular, and rhythmically irregular primes prior to performing a grammaticality judgement task. The order of the experimental blocks was manipulated such that participants listened to the regular prime first and the irregular prime last in one condition (Regular-Silence-Irregular), and vice versa (Irregular-Silence-Regular). Based on recent work in agreement attraction (Franck & Wagers, under review), linguistic stimuli were constructed in a semi-artificial Jabberwocky language to eliminate semantic effects. Half the sentences were correct while the other half contained a subject-verb number agreement violation. Sentences were presented auditorily. Additionally, participants also did two types of non-linguistic tasks: (a) structure-based tasks of rhythm processing included beat anticipation (Pagliarini, 2015) as well as rhythm and beat discrimination (Zentner & Strauss, 2017), while (b) non-structure-based tasks involved auditory attention (Schwartze et al., 2013) and processing speed (Pagliarini, 2015). Data were analysed using generalized linear mixed effects models and parametric tests. Preliminary results from a pilot study indicate that the Regular-Silence-Irregular condition led to a significant performance improvement across blocks within the grammaticality judgement task, absent in the Irregular-Silence-Regular condition, as well as higher performance in structure-based non-linguistic tasks, but not in attention or processing speed. However, the full experiment that implemented the order of primes as a within-subject condition was unable to replicate these results.