Is Theory Fading Away from Reality? Examining the Pathology Rather than the Technology to Understand Potential Personality Changes

Haeusermann et al. (2023) draw three overall conclusions from their study on closed loop neuromodulation and self-perception in clinical treatment of refractory epilepsy. The first is that closed-loop neuromodulation devices did not substantially change epileptic patient’s personalities or self-perception postoperatively. The second is that some patients and caregivers attributed observed changes in personality and self-perception to the epilepsy itself and not to the DBS treatments. The third is that the devices provided participants with novel ways to make sense of their illness. These findings further demonstrate a misalignment between some neuroethicists’ concerns about putative postoperative changes to personality, and the empirical evidence for such changes. Haeusermann et al. nonetheless concede that “neurotechnology directed at persisting rather than episodic clinical phenomena could have greater implications for personality or self-perception, either because they operate more continuously or are directed at clinical phenomena that are more stably integrated into patients’ self-concepts” (41). We acknowledge that the hypothesis that participants did not report changes because they were only episodically and not continually stimulated offers an interesting line for future investigation. Nonetheless, we would like to propose that potential postoperative personality changes might be correlated with the pathophysiology itself, rather than the stimulation effects of the technology. Generally, we advance the view that unintended effects solely induced by the technology cannot be excluded per se. Regardless, this comment aims to highlight that ethicists’ starting premise should be that patients suffering from diverse pathophysiology, or patients who are treated with stimulation in different brain regions and with differing parameters, would likely not react in the same way to treatment. Determining whether continuous or episodic DBS stimulation causally affects a patient’s personality, identity, agency, autonomy, authenticity, and self (PIAAAS) is a crucial question for users, families, and clinicians (Gilbert, Via~ na, and Ineichen 2021a, 2021b; Bluhm and Cabrera 2019; Pugh 2020). Nonetheless, understanding the term “cause” in the context of continuous or episodic brain stimulation is philosophically and scientifically difficult to achieve, for at least six reasons, some of which are identified by Haeusermann et al. First, if DBS is considered a necessary cause, it would imply that the effect (in our case, change in PIAAAS) only ever co-exists with the cause (DBS). We doubt there are many ethicists or clinicians advocating for this view because it would entail always seeing change in PIAAAS following DBS. We are not aware of evidence demonstrating that all DBS subjects experience unintended PIAAAS changes. Second, as the Haeusermann et al. study has shown, a patient’s self-concept (understood as the diverse ways a subject interprets themselves as an agent with a pathology) is often critical to their treatment trajectory outcomes, implying that non-DBS factors are conspicuously relevant. Third, other studies have shown that the more patients felt preoperatively alienated by their illness, the more they experienced self-estrangement following DBS (Gilbert et al. 2017). Fourth, reported patient experiences of preoperative self-image issues in relation to their pathology has contributed to radical psychological rejection of implanted brain-computer interfaces (Gilbert et al. 2019). Fifth, Haeusermann et al. note that patient’s seizures and side-effects of non-DBS treatments were “barriers to becoming who they wanted to be or imagined themselves to be” (39) and that these “profoundly affected their sense of. self” (39). However, the aforementioned barriers to achieving goals, frustration with failing to obtain goals, and the