Preparing the ethical future of deep brain stimulation

Deep brain stimulation for refractory epilepsy

Deep brain stimulation (DBS) is a method of treatment utilized to control medically refractory epilepsy (RE). Patients with medically refractory epilepsy who do not achieve satisfactory control of seizures with pharmacological treatment or surgical resection of the epileptic focus and those who do not qualify for surgery could benefit from DBS. The most frequently used stereotactic targets for DBS are the anterior thalamic nucleus, subthalamic nucleus, central-medial thalamic nucleus, hippocampus, amygdala and cerebellum. The DBS is believed to be an effective method of treatment for various types of epilepsy among adults and adolescents. Side effects may be associated with implantation of electrodes and with the stimulation itself. An increasing number of publications and growing interest in DBS application for RE may result in standardization of the qualification and treatment protocol for RE with DBS.

The ethics of research on deep brain stimulation for depression: decisional capacity and therapeutic misconception

Research on deep brain stimulation (DBS) for treatment-resistant depression appears promising, but concerns have been raised about the decisional capacity of severely depressed patients and their potential misconceptions about the research. We assessed 31 DBS research participants with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), a well-validated capacity measure, and with a scale to measure therapeutic misconception, which occurs when subjects do not recognize key differences between treatment and clinical research. Correlations with baseline depressive symptoms were explored. Subjects' performance on the MacCAT-CR was excellent, but therapeutic misconception was still apparent. A trend toward significance was found in the correlation between baseline depression ratings and total therapeutic misconception score. Responses to open-ended prompts revealed both reassuring and concerning statements related to expectations of risk, benefit, and individualization. Even severely depressed patients did not manifest impairments in their capacity to consent to DBS research. Therapeutic misconception, however, remained prevalent.

Strategies for the return of behavioral surgery

BACKGROUND

Behavioral surgery (BS) is resurging because of unmet clinical need, advances in basic sciences, neuroimaging, neurostimulation, and stereotaxy. However, there is a danger that BS will fall unless acceptable strategies are adopted by BS providers.

METHODS

A critical review of conditions leading to rise of psychosurgery (PS) and concerns resulting in its fall was conducted to learn lessons and safeguard BS of the future.

RESULTS

PS rose and spread in 1960 like wildfire without adequate preclinical and clinical studies. Hundreds of patients had PS without adequate preoperative diagnosis or assessment, proper consent, and non-objective reporting of outcome. Furthermore, there was public opposition against PS because of its potential abuse to control violent behavior and dissidents. Advances in neurostimulation, neuroimaging, and stereotaxy, and emergence of treatment-resistant mental disorders led to increased interest in BS. Several recent studies have shown BS to be safe and effective. However, concerns related to strength of evidence, safety, efficacy, consent, and objectivity of studies have been raised. Unless clinical and regulatory governance structures are adopted in each jurisdiction, BS will face the same fate as that of PS in the past.

CONCLUSION

THE FUTURE OF BS AS A SAFE AND EFFECTIVE THERAPY IS DEPENDENT UPON ADOPTING CLEAR MORAL ETHICAL AND GOVERNANCE STANDARDS ON THE FOLLOWING LINES: Patients must have failed adequate therapies; must be assessed by psychiatrist-led multidisciplinary teams; patients' abilities to give consent and diagnosis must be verified by independent authorities designated for this purpose by the state; and the independent authority must also decide whether the teams were adequately trained to perform BS.

Deep brain stimulation and ethics: perspectives from a multisite qualitative study of Canadian neurosurgical centers

OBJECTIVE

Deep brain stimulation (DBS) is an approved neurosurgical intervention for motor disorders such as Parkinson disease. The emergence of psychiatric uses for DBS combined with the fact that it is an invasive and expensive procedure creates important ethical and social challenges in the delivery of care that need further examination. We endeavored to examine health care provider perspectives on ethical and social challenges encountered in DBS.

METHODS

Health care providers working in Canadian DBS surgery programs participated in a semistructured interview to identify and characterize ethical and social challenges of DBS. A content analysis of the interviews was conducted.

RESULTS

Several key ethical issues, such as patient screening and resource allocation, were identified by members of neurosurgical teams. Providers described challenges in selecting patients for DBS on the basis of unclear evidence-based guidance regarding behavioral issues or cognitive criteria. Varied contexts of resource allocation, including some very challenging schemas, were also reported. In addition, the management of patients in the community was highlighted as a source of ethical and clinical complexity, given the need for coordinated long-term care.

CONCLUSIONS

This study provides insights into the complexity of ethical challenges that providers face in the use of DBS across different neurosurgical centers. We propose actions for health care providers for the long-term care and postoperative monitoring of patients with DBS. More data on patient perspectives in DBS would complement the understanding of key challenges, as well as contribute to best practices, for patient selection, management, and resource allocation.

Enrolling in deep brain stimulation research for depression: influences on potential subjects' decision making

BACKGROUND

Ethical concerns regarding early-phase clinical trials of DBS for treatment-resistant depression (TRD) include the possibility that participants' decisions to enroll might be motivated by unrealistic expectations of personal benefit or minimization of risks.

METHODS

Thematic analyses were conducted on a sample of 26 adults considering participation in two DBS trials. Influences on the decision making of these potential DBS trial participants were derived from responses to questions posed in the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), a semi-structured interview designed to evaluate decisional capacity to consent to research.

RESULTS

Participants cited numerous factors as influential in their enrollment decisions, including perceived lack of other treatment options, desire to take initiative, beliefs about DBS as a novel treatment, possibility of DBS efficacy, hoped-for improvements, potential risks and disadvantages of DBS or clinical trial participation, and altruism. No individual expressed a set of motivations or influencing factors that suggested compromised decision-making capacity or diminished voluntariness of decision making.

CONCLUSIONS

These results suggest that individuals make the decision to enroll in early-phase trials of DBS for TRD based on a number of complex and sometimes idiosyncratic considerations, and that the trials that were studied utilized sufficiently robust informed consent processes. These findings offer evidence that the emerging research area of DBS can be advanced in an ethically sound manner, provided that safeguards and processes for discussing trials with participants are carefully and proactively enacted.

Examining reports and policies on cognitive enhancement: approaches, rationale, and recommendations

The phenomenon of cognitive enhancement is attracting attention in bioethics literature and beyond, in public policy. In response, three bodies--the British Medical Association (BMA); the Commission de l'éthique de la Science et de la technologie (CEST) du Québec; the American Academy of Neurology (AAN)--have produced reports and guidance on this topic. To gain insights into different public policy approaches, rationales, and recommendations on the topic, we analyzed these reports in depth. We found convergence on the definition (with the exception of the CEST) of cognitive enhancement. However, we noted a lack of critical reflection with respect to the underlying rationale for developing these reports, i.e., that cognitive enhancement practices are rampant and represent major social changes. As it currently stands, cognitive enhancement is constituted in a way that challenges the creation of coherent and effective policy recommendations. However, policy makers should not simply wait for definitional consensus and hope that on balance the benefits turn out to be greater than the risks. Some components of cognitive enhancement could be reduced down to clearly identified policy targets to be further examined. Then, if appropriate, policy should be created that is, amongst other criteria, beneficial to the majority of the population.

Deep brain stimulation, personal identity and policy

A range of implantable brain-interfacing devices (IBIDs) is currently in use and development for the treatment of movement disorders and disorders of mood, behaviour and thought. These include cochlear implants, deep brain stimulation (DBS), prosthetic limbs, and optogenetic interventions (the combined use of genetics and optics to control individual cells). While implantable non-brain devices, such as implantable cardioverter defibrillators, began receiving US Food and Drug Administration approval in 1980, the development of IBIDs is recent, with the approval of DBS for Parkinson's disease in 1997. The expansion in use of IBIDs from neurological to psychiatric conditions is even more recent, with current trials underway for a range of disorders including depression, OCD, addiction, Alzheimer's disease and Tourette's syndrome. Emerging applications of existing IBIDs and new devices in development differ from currently approved devices and applications in two potentially crucial ways: 1) They target conditions traditionally seen as psychiatric; and/or 2) They target and modify functions or traits tied closely to agency, personal identity and personhood. As such, understanding patients' and caregivers' conceptions of personal identity in the context of disease and treatment is important not only for the informed consent process, but also for questions of public policy.

Participants' Perceptions of Deep Brain Stimulation Research for Treatment-Resistant Depression: Risks, Benefits, and Therapeutic Misconception

BACKGROUND

Deep brain stimulation (DBS) for treatment-resistant depression (TRD) is the focus of great interest and numerous studies. Given the state of this research, the risks of DBS, the uncertainty of direct benefits, and the potential for therapeutic misconception (TM), examination of research participants' perspectives is critical to addressing concerns about the adequacy of consent among people with TRD.

METHODS

Among 31 participants considering DBS studies at two sites, self-report questionnaires were used to examine three dimensions of TM (eight true/false items). Additional Likert-scale items assessed perceptions of risks, potential benefits, and altruistic motivations.

RESULTS

Participants correctly identified the surgery itself as the riskiest study procedure, although only four participants rated the surgery as "high risk." Most participants rated the entire DBS study as "moderate" or lower risk. Participants rated the likelihood of others benefiting in the future more strongly than they did the likelihood of personal benefit. Participants held positive attitudes toward research, and were moderately altruistic. Nearly two-thirds of the 31 participants (64.5%) answered at least one of the true/false TM items incorrectly.

CONCLUSIONS

Individuals considering DBS studies for TRD demonstrated reasonable perceptions of risks and benefits, distinguished among procedural risks, and expressed hopes for personal benefit as well as altruism. Findings related to TM were mixed: Participants understood the experimental stage of DBS for depression and endorsed the possibility of no personal benefit, yet there was some evidence for TM. Although these findings are reassuring, investigators must nevertheless remain vigilant about identifying and addressing potential misconceptions.

Patients' perceptions of life shift after deep brain stimulation for primary dystonia--A qualitative study

Studies of deep brain stimulation for dystonia have shown significant motor improvement. However, patients' perceptions of surgery and its effects have been less studied. We aimed to explore perceptions of changes in life in patients with primary dystonia after deep brain stimulation. Thirteen patients underwent thematic interviews 8-60 months after pallidal deep brain stimulation. Interviews were transcribed verbatim and analyzed with grounded theory. Patients described a profound impact of dystonia on daily life. After surgery, physical changes with a more upright posture and fewer spasms translated into an easier, more satisfying life with greater confidence. Notwithstanding this positive outcome, the transition from a limited life before surgery to opportunities for a better life exhibited obstacles: The "new life" after deep brain stimulation was stressful, including concern about being dependent on the stimulator as well as having to deal with interfering side effects from deep brain stimulation. The whole coping process meant that patients had to quickly shift focus from struggling to adapt to a slowly progressive disorder to adjustment to a life with possibilities, but also with new challenges. In this demanding transition process, patients wished to be offered better professional guidance and support. Even though deep brain stimulation provides people with primary dystonia with a potential for better mobility and more confidence, patients experienced new challenges and expressed the need for support and counseling after surgery. Grounded theory is a useful method to highlight patients' own experience and contributes to a deeper understanding of the impact of deep brain stimulation on patients with dystonia.

Deep brain stimulation in the media: over-optimistic portrayals call for a new strategy involving journalists and scientists in ethical debates

Deep brain stimulation (DBS) is optimistically portrayed in contemporary media. This already happened with psychosurgery during the first half of the twentieth century. The tendency of popular media to hype the benefits of DBS therapies, without equally highlighting risks, fosters public expectations also due to the lack of ethical analysis in the scientific literature. Media are not expected (and often not prepared) to raise the ethical issues which remain unaddressed by the scientific community. To obtain a more objective portrayal of DBS in the media, a deeper collaboration between the science community and journalists, and particularly specialized ones, must be promoted. Access to databases and articles, directly or through science media centers, has also been proven effective in increasing the quality of reporting. This article has three main objectives. Firstly, to explore the past media coverage of leukotomy, and to examine its widespread acceptance and the neglect of ethical issues in its depiction. Secondly, to describe how current enthusiastic coverage of DBS causes excessive optimism and neglect of ethical issues in patients. Thirdly, to discuss communication models and strategies to enhance media and science responsibility.

Ethical guidance for the management of conflicts of interest for researchers, engineers and clinicians engaged in the development of therapeutic deep brain stimulation

The clinical promise of deep brain stimulation (DBS) for neuropsychiatric conditions is coupled with the potential for ethical conflicts of interest because the work is so heavily reliant upon collaborations between academia, industry and the clinic. To foster transparency and public trust, we offer ethical guidance for the management of conflicts of interest in the conduct of DBS research and practice so that this nascent field can better balance competing goods and engineer new and better strategies for the amelioration of human suffering. We also hope that our ethical analysis will be of relevance to those working with other related neuroprosthetic devices, such brain-computer interfaces and neural arrays, which naturally share many of the same concerns.

Ethical issues in deep brain stimulation

Deep brain stimulation (DBS) is currently used to treat neurological disorders like Parkinson's disease, essential tremor, and dystonia, and is explored as an experimental treatment for psychiatric disorders like major depression and obsessive compulsive disorder. This mini review discusses ethical issues in DBS treatment and research, as they have been discussed in the medical and ethical literature. With regard to DBS treatment, the most important issues are balancing risks and benefits and ensuring respect for the autonomous wish of the patient. This implies special attention to patient selection, psycho-social impact of treatment, effects on personal identity, and treatment of children. Moreover, it implies a careful informed consent process in which unrealistic expectations of patients and their families are addressed and in which special attention is given to competence. In the context of research, the fundamental ethical challenge is to promote high-quality scientific research in the interest of future patients, while at the same time safeguarding the rights and interests of vulnerable research subjects. Several guidelines have been proposed to ensure this. One of the preconditions to further development of responsible and transparent research practices is the establishment of a comprehensive registry.

A review of social and relational aspects of deep brain stimulation in Parkinson's disease informed by healthcare provider experiences

Background. Although the clinical effectiveness of deep brain stimulation (DBS) in Parkinson's disease is established, there has been less examination of its social aspects. Methods and Results. Building on qualitative comments provided by healthcare providers, we present four different social and relational issues (need for social support, changes in relationships (with self and partner) and challenges with regards to occupation and the social system). We review the literature from multiple disciplines on each issue. We comment on their ethical implications and conclude by establishing the future prospects for research with the possible expansion of DBS for psychiatric indications. Conclusions. Our review demonstrates that there are varied social issues involved in DBS. These issues may have significant impacts on the perceived outcome of DBS by patients. Moreover, the fact that the social impact of DBS is still not well understood in emerging psychiatric indications presents an important area for future examination.

Health, Happiness and Human Enhancement-Dealing with Unexpected Effects of Deep Brain Stimulation

Deep Brain Stimulation (DBS) is a treatment involving the implantation of electrodes into the brain. Presently, it is used for neurological disorders like Parkinson's disease, but indications are expanding to psychiatric disorders such as depression, addiction and Obsessive Compulsive Disorder (OCD). Theoretically, it may be possible to use DBS for the enhancement of various mental functions. This article discusses a case of an OCD patient who felt very happy with the DBS treatment, even though her symptoms were not reduced. First, it is explored if the argument that 'doctors are not in the business of trading happiness', as used by her psychiatrist to justify his discontinuation of the DBS treatment, holds. The relationship between enhancement and the goals of medicine is discussed and it is concluded that even though the goals of medicine do not set strict limits and may even include certain types of enhancement, there are some good reasons for limiting the kind of things doctors are required or allowed to do. Next, the case is discussed from the perspective of beneficence and autonomy. It is argued that making people feel good is not the same as enhancing their well-being and that it is unlikely-though not absolutely impossible-that the well-being of the happy OCD patient is really improved. Finally, some concerns regarding the autonomy of a request made under the influence of DBS treatment are considered.

Deep brain stimulation for Tourette syndrome: a prospective pilot study in Japan

OBJECTIVE

Refractory Tourette syndrome (TS) disturbs the social life of patients. Deep brain stimulation (DBS) has recently been applied to relieve severe tics. We report a prospective open-labeled case series of DBS for TS as a pilot study.

CASES AND METHODS

Three patients (19-21 years old, one male) with refractory TS were treated with DBS. They were targeted at the centromedian-parafascicular complex-ventral oral thalamic nuclei of the bilateral thalami.

RESULTS

The scores for the Yale Global Tic Severity Scale decreased from 42.7 ± 2.7 (before DBS) to 26.0 ± 1.7 (one year after DBS) (means ± standard error of means). Intelligence levels of the patients showed no change after surgery. There was no morbidity or mortality. All patients presented an increase in satisfaction with activities of daily living.

CONCLUSIONS

These results support the safety and efficacy of thalamic DBS for TS.

Ethical Issues in Deep Brain Stimulation Research for Treatment-Resistant Depression: Focus on Risk and Consent

Deep brain stimulation (DBS) is currently in pivotal trials as an intervention for treatment-resistant depression (TRD). Although offering hope for TRD, DBS also provokes ethical concerns-particularly about decision-making capacity of people with depression-among bioethicists, investigators, institutional review boards, and the public. Here, we examine this critical issue of informed consent for DBS research using available evidence regarding decision-making capacity and depression. Further, we explore the implications of the nature of TRD as well as that of the intervention (invasive brain surgery) for informed consent. Based on these analyses, we argue that additional safeguards specific to DBS research for TRD, beyond those that might be used in any higher risk study, are not supported by available empirical evidence. We nevertheless underscore the limited data on such invasive procedures in severely ill psychiatric patients and advocate a research agenda for the systematic study of ethical issues raised by these research endeavors.

Simulation and assessment of cerebrovascular damage in deep brain stimulation using a stereotactic atlas of vasculature and structure derived from multiple 3- and 7-tesla scans

Object

The most severe complication of deep brain stimulation (DBS) is intracranial hemorrhage. Detailed knowledge of the cerebrovasculature could reduce the rate of this disorder. Morphological scans typically acquired in stereotactic and functional neurosurgery (SFN) by using 1.5-T (or sometimes even 3-T) imaging units poorly depict the vasculature. Advanced angiographic imaging, including 3- and 7-T 3D time-of-flight and susceptibility weighted imaging as well as 320-slice CT angiography, depict the vessels in great detail. However, these acquisitions are not used in SFN clinical practice, and robust methods for their processing are not available yet. Therefore, the authors proposed the use of a detailed 3D stereotactic cerebrovascular atlas to assist in SFN planning and to potentially reduce DBS-induced hemorrhage.

Methods

A very detailed 3D cerebrovascular atlas of arteries, veins, and dural sinuses was constructed from multiple 3- and 7-T scans. The atlas contained > 900 vessels, each labeled with a name and diameter with the smallest having a 90-μm diameter. The cortical areas, ventricular system, and subcortical structures were fully segmented and labeled, including the main stereotactic target structures: subthalamic nucleus, ventral intermediate nucleus of the thalamus, and internal globus pallidus. The authors also developed a computer simulator with the embedded atlas that was able to compute the effective electrode trajectory by minimizing penetration of the cerebrovascular system and vital brain structures by a DBS electrode. The simulator provides the neurosurgeon with functions for atlas manipulation, target selection, trajectory planning and editing, 3D display and manipulation, and electrode-brain penetration calculation.

Results

This simulation demonstrated that a DBS electrode inserted in the middle frontal gyrus may intersect several arteries and veins including 1) the anteromedial frontal artery of the anterior cerebral artery as well as the prefrontal artery and the precentral sulcus artery of the middle cerebral artery (range of diameters 0.4–0.6 mm); and 2) the prefrontal, anterior caudate, and medullary veins (range of diameters 0.1–2.3 mm). This work also shows that field strength and pulse sequence have a substantial impact on vessel depiction. The numbers of 3D vascular segments are 215, 363, and 907 for 1.5-, 3-, and 7-T scans, respectively.

Conclusions

Inserting devices into the brain during microrecording and stimulation may cause microbleeds not discernible on standard scans. A small change in the location of the DBS electrode can result in a major change for the patient. The described simulation increases the neurosurgeon's awareness of this phenomenon. The simulator enables the neurosurgeon to analyze the spatial relationships between the track and the cerebrovasculature, ventricles, subcortical structures, and cortical areas, which allows the DBS electrode to be placed more effectively, and thus potentially reducing the invasiveness of the stimulation procedure for the patient.

Did My Brain Implant Make Me Do It? Questions Raised by DBS Regarding Psychological Continuity, Responsibility for Action and Mental Competence

Deep brain stimulation (DBS) is a well-accepted treatment for movement disorders and is currently explored as a treatment option for various neurological and psychiatric disorders. Several case studies suggest that DBS may, in some patients, influence mental states critical to personality to such an extent that it affects an individual's personal identity, i.e. the experience of psychological continuity, of persisting through time as the same person. Without questioning the usefulness of DBS as a treatment option for various serious and treatment refractory conditions, the potential of disruptions of psychological continuity raises a number of ethical and legal questions. An important question is that of legal responsibility if DBS induced changes in a patient's personality result in damage caused by undesirable or even deviant behavior. Disruptions in psychological continuity can in some cases also have an effect on an individual's mental competence. This capacity is necessary in order to obtain informed consent to start, continue or stop treatment, and it is therefore not only important from an ethical point of view but also has legal consequences. Taking the existing literature and the Dutch legal system as a starting point, the present paper discusses the implications of DBS induced disruptions in psychological continuity for a patient's responsibility for action and competence of decision and raises a number of questions that need further research.

Contemporary neuroscience in the media

Technological innovations in neuroscience have opened new windows to the understanding of brain function and the neuronal underpinnings of brain activity in neuropsychiatric disorders and social behavior. Public interest and support for neuroscience research through initiatives like the Decade of the Brain project and increasingly diverse brain-related initiatives have created new interfaces between neuroscience and society. Against this backdrop of dynamic innovation, we set out to examine how different features of neuroscience are depicted in print media. We used the 'guided news' function of the LexisNexis Academic database with keyword searches to find news articles published between 1995 and 2004 in major U.S. and U.K. English-language news sources. We performed searches on headlines, lead paragraphs, and body terms to maximize search yields. All articles were coded for overall tone of coverage, details on reported studies, presence of ethical, legal, and social discussion as well as the emerging interpretations of neuroscience - in the form of neuro-essentialism, neuro-realism, and neuro-policy. We found that print media coverage of the use of neurotechnology for diagnosis or therapy in neuropsychiatric disorders was generally optimistic. We also found that, even within articles that were identified as research reports, many did not provide details about research studies. We also gained additional insights into the previously identified phenomena of neuro-essentialism, neuro-realism, and neuro-policy showing some profound impacts of neuroscience on personal identity and policy-making. Our results highlight the implications of transfer of neuroscience knowledge to society given the substantial and authoritative weight ascribed to neuroscience knowledge in defining who we are. We also discuss the impact of these findings on neuroscience and on the respective contributions of the social sciences and the biological sciences in contemporary psychiatry and mental health policy.