-/- Zuk et al. (2023) examined researchers’ views on how deep brain stimulation may impact patients’ personality, mood, and behaviour (PMB). The team found that experts vary substantially in the notion of personality they employ. However, despite noting the lack of conceptual precision, no attempt was made at scientifically defining any of the involved concepts, so that the results of the different interviews remain largely incommensurable. In this comment, I am doing the interpretative work that the authors should have undertaken (...) following the descriptive part of the paper: first, disentangling the PMB cluster by defining what exactly constitutes personality, mood, and behaviour; and secondly, conceptualising the notion of personality change. I am arguing that what sets personality changes apart from other modifications is diachronic persistence. (shrink)