This paper analyses the role of prosody in parenthetical insertions, a type of structure that is extremely common in both speech and writing. The materials under study come from a corpus of spontaneous speech acts in Central Catalan (with varying degrees of spontaneity) from which a corpus of oral parenthetical insertions has been compiled. The prototypical prosodic features of a parenthetical insertion in Catalan are: prosodic autonomy, limited extension, production in between pauses or final pause, tendency towards acceleration, fall in intensity, lower pitch range and, finally, falling or rising melodic pattern. While the final fall is the most frequent pattern in spontaneous conversations with a high degree of confidence between interlocutors, a final rising structure is found in interviews in which the degree of confidence between participants is smaller, their roles are unequal, and the interviewed constructs a narrative discourse. We thus suggest that the pitch contour of parenthetical insertions is related to formality and discourse typology (in this case, narrative vs. dialogue). Bearing in mind the discursive functions performed by these insertions, we propose a typology which classifies them with regards to two main functions: completion of information, and modalisation.