The aim of this work is to study how different aspects of subtitled films are understood and memorised, in relation to the viewers' knowledge of the on-screen languages. Vocabulary acquisition is also evaluated, depending on the order in which the languages are presented on the screen (dialogues and subtitles). Three series of experiments are presented in order toexamine the role of subtitles in each of these three mechanisms. The processing of three dimensions of a film (visual, dialogue and situation) is evaluated, depending on the languages on the screen and the participants' knowledge of them. Results indicate a global facilitating effect of subtitles when they are necessary, as opposed to a global negative effect when they are not needed. Next, the effect of subtitles on film memorisation is examined, depending on the type of subtitling and the degree of salience of the information tested. An effect of the type of subtitles is found on comprehension and data retrieval, especially for elements that are considered most central to the plot. Finally, vocabulary acquisition possibilities are measured, depending on the type of subtitles, on the number of viewings of the film and on viewing instructions directing attention to the dialogues. The reversed version (dialogues in L1, subtitles in L2) lead to the best restitution level, particularly after the second viewing of the film. The viewing instructions also have an effect on word restitution. The results are interpreted in the light of attention and cognitive load theories, within the framework of various multimedia learning models.
