Evidence-Based Neuroethics, Deep Brain Stimulation and Personality - Deflating, but not Bursting, the Bubble.

Gilbert et al. have raised important questions about the empirical grounding of neuroethical analyses of the apparent phenomenon of Deep Brain Stimulation 'causing' personality changes. In this paper, we consider how to make neuroethical claims appropriately calibrated to existing evidence, and the role that philosophical neuroethics has to play in this enterprise of 'evidence-based neuroethics'. In the first half of the paper, we begin by highlighting the challenges we face in investigating changes to PIAAAS following DBS, explaining how different trial designs may be of different degrees of utility, depending on how changes to PIAAAS following DBS are manifested. In particular, we suggest that the trial designs Gilbert et al. call for may not be able to tell us whether or not DBS directly causes changes to personality. However, we suggest that this is not the most significant question about this phenomenon; the most significant question is whether these changes should matter morally, however they are caused. We go on to suggest that neuroethical analyses of novel neuro-interventions should be carried out in accordance with the levels of evidence hierarchy outlined by the Centre for Evidence-Based Medicine (CEBM), and explain different ways in which neuroethical analyses of changes to PIAAAS can be evidence-based on this framework. In the second half of the paper, we explain how philosophical neuroethics can play an important role in contributing to mechanism-based reasoning about potential effects on PIAAAS following DBS, a form of evidence that is also incorporated into the CEBM levels of evidence hierarchy.

Brainjacking in deep brain stimulation and autonomy.

'Brainjacking' refers to the exercise of unauthorized control of another's electronic brain implant. Whilst the possibility of hacking a Brain-Computer Interface (BCI) has already been proven in both experimental and real-life settings, there is reason to believe that it will soon be possible to interfere with the software settings of the Implanted Pulse Generators (IPGs) that play a central role in Deep Brain Stimulation (DBS) systems. Whilst brainjacking raises ethical concerns pertaining to privacy and physical or psychological harm, we claim that the possibility of brainjacking DBS raises particularly profound concerns about individual autonomy, since the possibility of hacking such devices raises the prospect of third parties exerting influence over the neural circuits underpinning the subject's cognitive, emotional and motivational states. However, although it seems natural to assume that brainjacking represents a profound threat to individual autonomy, we suggest that the implications of brainjacking for individual autonomy are complicated by the fact that technologies targeted by brainjacking often serve to enhance certain aspects of the user's autonomy. The difficulty of ascertaining the implications of brainjacking DBS for individual autonomy is exacerbated by the varied understandings of autonomy in the neuroethical and philosophical literature. In this paper, we seek to bring some conceptual clarity to this area by mapping out some of the prominent views concerning the different dimension of autonomous agency, and the implications of brainjacking DBS for each dimension. Drawing on three hypothetical case studies, we show that there could plausibly be some circumstances in which brainjacking could potentially be carried out in ways that could serve to enhance certain dimensions of the target's autonomy. Our analysis raises further questions about the power, scope, and necessity of obtaining prior consent in seeking to protect patient autonomy when directly interfering with their neural states, in particular in the context of self-regulating closed-loop stimulation devices.

Deep brain stimulation: An overview of history, methods, and future developments.

Deep brain stimulation has already revolutionised the clinical management of treatment-resistant movement disorders and offers novel treatment options for an increasing range of neurological and psychiatric illnesses. In this article, we briefly review the history of deep brain stimulation, particularly focusing on the last 50 years, which have seen rapid development in the safety and efficacy of deep brain stimulation. We then discuss the current state of the art in deep brain stimulation, focusing on emerging indications and recent technological advances that have improved the field. Finally, we consider the future developments in technology, technique, and research that will impact deep brain stimulation; particularly focusing on closed-loop stimulation techniques and emerging techniques such as optogenetics, cybersecurity risk, implantation timing, and impediments to undertaking high-quality research.

Unexpected Complications of Novel Deep Brain Stimulation Treatments: Ethical Issues and Clinical Recommendations.

BACKGROUND: Innovative neurosurgical treatments present a number of known risks, the natures and probabilities of which can be adequately communicated to patients via the standard procedures governing obtaining informed consent. However, due to their novelty, these treatments also come with unknown risks, which require an augmented approach to obtaining informed consent. OBJECTIVE: This paper aims to discuss and provide concrete procedural guidance on the ethical issues raised by serious unexpected complications of novel deep brain stimulation treatments. APPROACH: We illustrate our analysis using a case study of the unexpected development of recurrent stereotyped events in patients following the use of deep brain stimulation (DBS) to treat severe chronic pain. Examining these unexpected complications in light of medical ethical principles, we argue that serious complications of novel DBS treatments do not necessarily make it unethical to offer the intervention to eligible patients. However, the difficulty the clinician faces in determining whether the intervention is in the patient's best interests generates reasons to take extra steps to promote the autonomous decision making of these patients. CONCLUSION AND RECOMMENDATIONS: We conclude with clinical recommendations, including details of an augmented consent process for novel DBS treatment.

Long-Term Results of Deep Brain Stimulation of the Anterior Cingulate Cortex for Neuropathic Pain.

BACKGROUND: Deep brain stimulation (DBS) of the anterior cingulate cortex (ACC) is a recent technique that has shown some promising short-term results in patients with chronic refractory neuropathic pain. Three years after the first case series, we assessed its efficacy on a larger cohort, with longer follow-up. METHODS: Twenty-four patients (19 males; average age, 49.1 years) with neuropathic pain underwent bilateral ACC DBS. Patient-reported outcome measures were collected before and after surgery, using the Numerical Rating Scale (NRS), Short-Form 36 quality of life (SF-36), McGill Pain Questionnaire (MPQ), and EuroQol 5-domain quality of life (EQ-5D) questionnaire. RESULTS: Twenty-two patients after a trial week were fully internalized and 12 had a mean follow-up of 38.9 months. Six months after surgery the mean NRS score decreased from 8.0 to 4.27 (P = 0.004). There was a significant improvement in the MPQ (mean, -36%; P = 0.021) and EQ-5D score significantly decreased (mean, -21%; P = 0.036). The physical functioning domain of SF-36 was significantly improved (mean, +54.2%; P = 0.01). Furthermore, in 83% of these patients, at 6 months, NRS score was improved by 60% (P < 0.001) and MPQ decreased by 47% (P < 0.01). After 1 year, NRS score decreased by 43% (P < 0.01), EQ-5D was significantly reduced (mean, -30.8; P = 0.05) and significant improvements were also observed for different domains of the SF-36. At longer follow-ups, efficacy was sustained up to 42 months in some patients, with an NRS score as low as 3. CONCLUSIONS: Follow-up results confirm that ACC DBS alleviates chronic neuropathic pain refractory to pharmacotherapy and improves quality of life in many patients.

Brainjacking: Implant Security Issues in Invasive Neuromodulation.

The security of medical devices is critical to good patient care, especially when the devices are implanted. In light of recent developments in information security, there is reason to be concerned that medical implants are vulnerable to attack. The ability of attackers to exert malicious control over brain implants ("brainjacking") has unique challenges that we address in this review, with particular focus on deep brain stimulation implants. To illustrate the potential severity of this risk, we identify several mechanisms through which attackers could manipulate patients if unauthorized access to an implant can be achieved. These include blind attacks in which the attacker requires no patient-specific knowledge and targeted attacks that require patient-specific information. Blind attacks include cessation of stimulation, draining implant batteries, inducing tissue damage, and information theft. Targeted attacks include impairment of motor function, alteration of impulse control, modification of emotions or affect, induction of pain, and modulation of the reward system. We also discuss the limitations inherent in designing implants and the trade-offs that must be made to balance device security with battery life and practicality. We conclude that researchers, clinicians, manufacturers, and regulatory bodies should cooperate to minimize the risk posed by brainjacking.

Inhibition of DNA-repair genes Ercc1 and Mgmt enhances temozolomide efficacy in gliomas treatment: a pre-clinical study.

Gliomas are the most common primary brain tumors. To date, therapies do not allow curing patients, and glioblastomas (GBMs) are associated with remarkably poor prognosis. This situation is at least partly due to intrinsic or acquired resistance to treatment, especially to chemotherapy. In 2005, temozolomide (TMZ) has become the first chemotherapeutic drug validated for GBM. Nevertheless TMZ efficacy depends on Mgmt status. While the methylation of Mgmt promoter was considered so far as a prognostic marker, its targeting is becoming an effective therapeutic opportunity. Thus, arrival of both TMZ and Mgmt illustrated that considerable progress can still be realized by optimizing adjuvant chemotherapy. A part of this progress could be accomplished in the future by overcoming residual resistance. The aim of the present study was to investigate the involvement of a set of other DNA-repair genes in glioma resistance to temozolomide. We focused on DNA-repair genes located in the commonly deleted chromosomal region in oligodendroglioma (1p/19q) highly correlated with patient response to chemotherapy. We measured effects of inhibition of ten DNA-repair genes expression using siRNAs on astrocytoma cell response to cisplatin (CDDP) and TMZ. SiRNAs targeting ercc1, ercc2, mutyh, and pnkp significantly sensitized cells to chemotherapy, increasing cell death by up to 25%. In vivo we observed a decrease of subcutaneous glioma tumor growth after injection of siRNA in conjunction with absorption of TMZ. We demonstrated in this pre-clinical study that targeting of DNA-repair genes such as Ercc1 could be used as an adjuvant chemosensitization treatment, similarly to Mgmt inhibition.