Two experiments using novel complex working memory span tasks were performed, both requiring the participants to remember a span of letters whilst being distracted by the processing of words. Word processing could either be self-referential (SRP) or not. In the first experiment recall performance was compared between SRP and non-SRP conditions using the same words. In the second experiment, we compared SRP and non-SRP in two tasks equalized in semantic processing but using different words. In both experiments recall performance was significantly lower after SRP compared to non-SRP, indicating that SRP has a disruptive effect on the recall task. A cognitive model implemented in PRIMs, using goal competition during SRP, interfering with rehearsal of letters, could account for the observed experimental results. If SRP interferes with subsequent tasks in this manner it should also interfere with tasks other than recall, such as SRP occurring in daily life.