The idea that deep brain stimulation (DBS) induces changes to personality, identity, agency, authenticity, autonomy and self (PIAAAS) is so deeply entrenched within neuroethics discourses that it has become an unchallenged narrative. In this article, we critically assess evidence about putative effects of DBS on PIAAAS. We conducted a literature review of more than 1535 articles to investigate the prevalence of scientific evidence regarding these potential DBS-induced changes. While we observed an increase in the number of publications in theoretical neuroethics that mention putative DBS-induced changes to patients’ postoperative PIAAAS, we found a critical lack of primary empirical studies corroborating these claims. Our findings strongly suggest that the theoretical neuroethics debate on putative effects of DBS relies on very limited empirical evidence and is, instead, reliant on unsubstantiated speculative assumptions probably in lieu of robust evidence. As such, this may reflect the likelihood of a speculative neuroethics bubble that may need to be deflated. Nevertheless, despite the low number of first-hand primary studies and large number of marginal and single case reports, potential postoperative DBS changes experienced by patients remain a critical ethical concern. We recommend further empirical research in order to enhance theoretical neuroethics work in the area. In particular, we call for the development of better instruments capable of capturing potential postoperative variations of PIAAAS.