The experience of a radical life transformation from living with the constant uncertainty of not knowing if and when a next adverse neurologic event will come, to successfully managing and preventing it with the assistance of an implantable BCI device, might first appear as a boost for patient autonomy. However, this study with the first six patients ever tested with an intelligent BCI for epilepsy suggests that the transformation does not necessarily bring with it only a sense of enhanced control and continuity in daily activities, but may have the effect of self-estrangement. Even though the number of patients enrolled in this trial is small, and the data are qualitative and not generalizable to a larger population, the findings are of important ethical concern and could serve to inform future clinical applications of such devices and the research that leads up to them.

We found in our sample that intelligent BCIs were perceived as beneficial by most patients in terms of an associated increased sense of control over their daily activities (Patients 1, 2, 5, 6). For most patients, it seems these intelligent BCI predictive functionalities generated changes in the perceived degree of control over their daily life activities, rather than changes in what constituted them as a person. However, one patient testified to strong experiences of embodied fusion of self with the device resulting in feelings of a new postoperative identity (Patient 6). Importantly, we found one case (Patient 3) of a patient experiencing distress and feeling a loss of control.

The narratives of Patient 6, for example, refer to a discontinuous transition from who she was pre-implantation to who she became after the intervention: the device helped the patient find what she understood to be her ‘true self’. In her case, she not only became functionally dependent on predictions of the BCI advisory system, but the technology was incorporated into her sense of self: “it becomes part of you. Because that’s what it did, it was me, it became me, […] with this device I found myself”. Therefore, for Patient 6, the BCI device became an extension of her self and fused with part of her body: i.e., an integral component of her embodied personal identity. As such, it affected her aspirational goals and augmented her activities of daily living as part of the process of self-definition and self-expression.

The experiences reported by the patients also suggest that the BCI advisory devices can induce an abrupt transition in a patient’s self-understanding as associated with the disappearance absence of symptoms. Finding onself changed through implantation can also result in a sense of postoperative self-estrangement. It is important to note that postoperative self-estrangement should be distinguished by deteriorative and restorative features (Gilbert et al. 2017; Gilbert 2017). The notion of self-estrangement exists in association with certain common feelings of a (1) loss of control (Patient 3 “[the BCI] made me feel I had no control” and (2) distorted perceptions of one’s capacities (Patient 6: “With the device I felt like I could do anything […] nothing could stop me”)—the first (1) being mostly associated with a deteriorative sense of the self, and the second (2) largely related to a restorative sense of the self.Footnote 4 It should be recognized that drawing on subjective or first-person phenomenological accounts of how a person feels about or experiences the BCI implant does not provide us with enough context to assess the objective accuracy of these accounts. Self-estrangement may occur, but is not necessarily perceived by the implanted patient (Thomson and Segrave 2017).Footnote 5

With respect to restorative features of self-estrangement, some patients perceived them as naturally occurring (Patient 2: “It is a natural consequent of the development of the algorithm”). The explanation for this may reside in the experience of changed embodiment with the patient coming to feel that the device is authentically a part of themselves. In this study, patients’ self-reports indicate that implanted advisory devices are experienced as increasing restorative powers (i.e., empowerment) over the self (Patient 6: “[The device] changed who that person was then and I found myself changing”).

On the other hand, in terms of deteriorative features of estrangement, Patient 3 experienced feeling a loss of control; that reflect an involuntary shift in their experience of the self. Some feelings of postoperative deterioration of the self were associated with a sense of powerlessness, resulting in severe distress. The notion of postoperative powerlessness has been associated with an inaptitude to overcome some induced psychological realities, for instance Patient 3 seemed not able to regain control of her depressive feelings. From this perspective, the prolonged absence of the capacities to regain control may have contributed to turning estrangement into harm (Gilbert 2015a, b). This finding supports the hypothesis that postoperative feelings of powerlessness play a crucial role in causing iatrogenic harm (Gilbert 2013a, 2015b).

Patient 3 presents an illustration of how the experience of having a BCI constantly monitor, identify and translate one’s brain activities impacts the implanted patient’s self-understanding. Sudden exposure to medical information that predicts upcoming chronic symptoms resulted in dramatic negative consequences to the self-image of certain patients. In the case of Patient 3, the information disclosed and exposed by the device did not corroborate the patient’s self-image and self-narrative. Patient 3 never associated herself with epilepsy: “I just kind of pretended that it didn’t really exist. I didn’t really see myself as an epilectic”.

However, being constantly alerted by the machine impressed upon her the reality of her symptoms, thus providing corroborating evidence of her disease state. This process exacerbated her predisposition to depression; in effect, she was unable to manage the information load returned by the device. In turn, this provoked a dramatic clash with her self-understanding: “I felt so weird all the time, before it I only felt strange having the seizure” (Patient 03).