This study examined whether ruminative style moderated the effects of expressive writing.

Sloan DM, Marx BP, Epstein EM, Dobbs JL. Expressive writing buffers against maladaptive rumination. Emotion. 2008 Apr;8(2):302-6. doi: 10.1037/1528-3542.8.2.302. PMID: 18410204.

The effect of emotional disclosure through expressive writing on available working memory (WM) capacity was examined in 2 semester-long experiments.

Klein, K., & Boals, A. (2001). Expressive writing can increase working memory capacity. Journal of Experimental Psychology: General, 130(3), 520–533. https://doi.org/10.1037/0096-3445.130.3.520