TABLE 3.

Researcher responses across main ethical concerns related to aDBS.

Ethical theme	Researcher responses
Data privacy and security	“I think the main concerns would be privacy of the data. We stream these data to external computers. Someone’s brain data is now […] it could be considered personal health information, in a way. Eventually, we may be able to decode specific things about that person’s identity and personality from their brain data. So, we do have to consider it as personal health information, even if it’s de-identified. At least if not now, then in the future, we’ll have to consider that” (R_011).
Risks and safety	“There’s the fact that we just don’t know that much about DBS and how it works. That’s the danger of doing any kind of experiment on humans directly, even though it’s pretty well understood, what the random risks are” (R_006).
Informed consent and patient understanding	“In many cases, the person who has a therapeutic relationship with the patient is also an investigator, and so there might be possible duress or coercion to participate in these studies” (R_023).
Automaticity and device programming	“My concern is that it might stimulate when it’s not supposed to, causing [an] unwanted side effect. Or the opposite, if it’s not stimulating when it’s supposed to causing the patient unnecessary suffering. Those are glitches that, as we develop these techniques, hopefully will not be an issue. But those are concerns that I have from an ethical perspective. And then, from a researcher point of view and a clinician, when is it going to be that moment [when] we’re satisfied with that signal and that response to stimulation” (R_020).
Autonomy and control	“I think we need to be careful in affording control of the device to the patient. For any stimulation of the reward system, there’s potential for self-abuse. There are restrictions [where] patients can turn the device off or on, but they can’t modulate it. That strikes me as a wise precaution” (R_026).
Patient selection and candidacy considerations	“When you have a population that does not have a sufficient response to pretty much everything [other treatments], and you can have a 60% response rate in that group [to aDBS], good lord, that’s incredible. I worry about the side effects of not doing something for those individuals” (R_018).
Post-trial access to care and device maintenance	“We basically thought, ethically, it would be best that they receive rechargeable non-sensing devices so that they can basically get this open-loop therapy for a long duration. I think those batteries last for like 9 years” (R_016).
Personality and identity	“In the study where we’re manipulating mood potentially, the goal is to improve mood, which most people would say would be a good thing. But then at some point, do you give somebody a new mood that changes their personality? There are a lot of ethical issues behind potentially manipulating people’s mood and personality [be]cause that could be a good thing or a bad thing” (R_010).