"Aggregation of misfolded proteins has been implicated in a number of neurodegenerative disorders including prion disease. In spite of intensive research, the detailed mechanisms of protein misfolding leading to protein aggregation remain unsolved. Here, we explore the capacity for bistability of several classes of mechanisms proposed in the literature and compatible with protein aggregation kinetic data sets (it has been shown that bistability explains thresholds phenomena observed in protein aggregation in vitro and in vivo). Using a novel method for bistability detection we find a plausible scenario for which the so called subsequent monomer addition model leads to bistability."