scholarly journals Electrodes in the brain: Some anthropological and ethical aspects of deep brain stimulation

2006 ◽  
Vol 5 ◽  
pp. 33-38
Author(s):  
Elizabeth Hildt

In the following text, medical, anthropological and ethical issues of deep brain stimulation, a medical technology in which electrodes implanted in the human brain electrically influence specified brain regions, will be discussed. After a brief account of the deep brain stimulation procedure and its chances and risks, anthropological and ethical aspects of the approach will be discussed. These relate to the reversibility of the procedure and to the patient?s capacity to control the effects it exerts in the brain, to modifications and fluctuations in a person?s character traits and individuality brought about by neurostim ulation, an d to the range of legitim ate, adequate uses of the deep brain stimulation approach. The paper concludes that deep brain stimulation should be confined to therapeutic contexts and to severe, otherwise treatment-refractory disorders in which the aim is to norm alize brain fun ctioning. A part from this, it sh ould not be used to m odify a person?s individ ual character traits and behaviour or to enhance human traits.

2021 ◽  
pp. 405-420
Author(s):  
Georg Northoff

Neuroethics, located at the interface of conceptual and empirical dimensions, carries major implications for psychiatry, such as the neuroscientific basis of ethical concepts as moral agency. Drawing on data in neuroscience, this chapter highlights issues central to psychiatric ethics. First, it addresses a reductionistic model of the brain, often conceived as purely neuronal, and then it discusses empirical data suggesting that the brain’s activity is strongly aligned to its respective social (e.g., relation to others) and ecological (e.g., relation to the environment and nature) contexts; this implies a relational rather than reductionist model. Second, it suggests that self (e.g., the experience or sense of a self) and personhood (e.g., the person as existent independent of experience) must also be understood in such a social and ecological and, therefore, relational and spatio-temporal sense. Ethical concepts like agency, therefore, cannot be limited solely to the person and brain, but must rather be understood in a relational and neuro-ecological/social way. Third, it discusses deep brain stimulation as a treatment that promotes enhancement. In sum, this chapter presents findings in neuroscience that carry major implications for our view of brain, mental features, psychiatric disorders, and ethical issues like agency, responsibility, and enhancement.


2007 ◽  
Vol 107 (5) ◽  
pp. 989-997 ◽  
Author(s):  
Yasushi Miyagi ◽  
Fumio Shima ◽  
Tomio Sasaki

Object The goal of this study was to focus on the tendency of brain shift during stereotactic neurosurgery and the shift's impact on the unilateral and bilateral implantation of electrodes for deep brain stimulation (DBS). Methods Eight unilateral and 10 bilateral DBS electrodes at 10 nuclei ventrales intermedii and 18 subthalamic nuclei were implanted in patients at Kaizuka Hospital with the aid of magnetic resonance (MR) imaging–guided and microelectrode-guided methods. Brain shift was assessed as changes in the 3D coordinates of the anterior and posterior commissures (AC and PC) with MR images before and immediately after the implantation surgery. The positions of the implanted electrodes, based on the midcommissural point and AC–PC line, were measured both on x-ray films (virtual position) during surgery and the postoperative MR images (actual position) obtained on the 7th day postoperatively. Results Contralateral and posterior shift of the AC and PC were the characteristics of unilateral and bilateral procedures, respectively. The authors suggest the following. 1) The first unilateral procedure elicits a unilateral air invasion, resulting in a contralateral brain shift. 2) During the second procedure in the bilateral surgery, the contralateral shift is reset to the midline and, at the same time, the anteroposterior support by the contralateral hemisphere against gravity is lost due to a bilateral air invasion, resulting in a significant posterior (caudal) shift. Conclusions To note the tendency of the brain to shift is very important for accurate implantation of a DBS electrode or high frequency thermocoagulation, as well as for the prediction of therapeutic and adverse effects of stereotactic surgery.


2011 ◽  
Vol 70 (suppl_1) ◽  
pp. ons114-ons124 ◽  
Author(s):  
Nova B. Thani ◽  
Arul Bala ◽  
Christopher R. P. Lind

Abstract BACKGROUND: Accurate placement of a probe to the deep regions of the brain is an important part of neurosurgery. In the modern era, magnetic resonance image (MRI)-based target planning with frame-based stereotaxis is the most common technique. OBJECTIVE: To quantify the inaccuracy in MRI-guided frame-based stereotaxis and to assess the relative contributions of frame movements and MRI distortion. METHODS: The MRI-directed implantable guide-tube technique was used to place carbothane stylettes before implantation of the deep brain stimulation electrodes. The coordinates of target, dural entry point, and other brain landmarks were compared between preoperative and intraoperative MRIs to determine the inaccuracy. RESULTS: The mean 3-dimensional inaccuracy of the stylette at the target was 1.8 mm (95% confidence interval [CI], 1.5-2.1. In deep brain stimulation surgery, the accuracy in the x and y (axial) planes is important; the mean axial inaccuracy was 1.4 mm (95% CI, 1.1-1.8). The maximal mean deviation of the head frame compared with brain over 24.1 ± 1.8 hours was 0.9 mm (95% CI, 0.5-1.1). The mean 3-dimensional inaccuracy of the dural entry point of the stylette was 1.8 mm (95% CI, 1.5-2.1), which is identical to that of the target. CONCLUSION: Stylette positions did deviate from the plan, albeit by 1.4 mm in the axial plane and 1.8 mm in 3-dimensional space. There was no difference between the accuracies at the dura and the target approximately 70 mm deep in the brain, suggesting potential feasibility for accurate planning along the whole trajectory.


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243438
Author(s):  
Hannah Ihme ◽  
Rainer K. W. Schwarting ◽  
Liana Melo-Thomas

Deep brain stimulation (DBS) of the colliculus inferior (IC) improves haloperidol-induced catalepsy and induces paradoxal kinesia in rats. Since the IC is part of the brain aversive system, DBS of this structure has long been related to aversive behavior in rats limiting its clinical use. This study aimed to improve intracollicular DBS parameters in order to avoid anxiogenic side effects while preserving motor improvements in rats. Catalepsy was induced by systemic haloperidol (0.5mg/kg) and after 60 min the bar test was performed during which a given rat received continuous (5 min, with or without pre-stimulation) or intermittent (5 x 1 min) DBS (30Hz, 200–600μA, pulse width 100μs). Only continuous DBS with pre-stimulation reduced catalepsy time. The rats were also submitted to the elevated plus maze (EPM) test and received either continuous stimulation with or without pre-stimulation, or sham treatment. Only rats receiving continuous DBS with pre-stimulation increased the time spent and the number of entries into the open arms of the EPM suggesting an anxiolytic effect. The present intracollicular DBS parameters induced motor improvements without any evidence of aversive behavior, pointing to the IC as an alternative DBS target to induce paradoxical kinesia improving motor deficits in parkinsonian patients.


2021 ◽  
Author(s):  
Maarten Bot ◽  
Anne-Fleur van Rootselaari ◽  
Vincent Odekerken ◽  
Joke Dijk ◽  
Rob M A de Bie ◽  
...  

Abstract BACKGROUND Dentato-rubro-thalamic tract (DRT) deep brain stimulation (DBS) suppresses tremor in essential tremor (ET) patients. However, DRT depiction through tractography can vary depending on the included brain regions. Moreover, it is unclear which section of the DRT is optimal for DBS. OBJECTIVE To evaluate deterministic DRT tractography and tremor control in DBS for ET. METHODS After DBS surgery, DRT tractography was conducted in 37 trajectories (20 ET patients). Per trajectory, 5 different DRT depictions with various regions of interest (ROI) were constructed. Comparison resulted in a DRT depiction with highest correspondence to intraoperative tremor control. This DRT depiction was subsequently used for evaluation of short-term postoperative adverse and beneficial effects. RESULTS Postoperative optimized DRT tractography employing the ROI motor cortex, posterior subthalamic area (PSA), and ipsilateral superior cerebellar peduncle and dentate nucleus best corresponded with intraoperative trajectories (92%) and active DBS contacts (93%) showing optimal tremor control. DRT tractography employing a red nucleus or ventral intermediate nucleus of the thalamus (VIM) ROI often resulted in a more medial course. Optimal stimulation was located in the section between VIM and PSA. CONCLUSION This optimized deterministic DRT tractography strongly correlates with optimal tremor control. This technique is readily implementable for prospective evaluation in DBS target planning for ET.


2018 ◽  
pp. 135-184
Author(s):  
Walter Glannon

This chapter discusses functional neurosurgery designed to modulate dysfunctional neural circuits mediating sensorimotor, cognitive, emotional, and volitional capacities. The chapter assesses the comparative benefits and risks of neural ablation and deep brain stimulation as the two most invasive forms of neuromodulation. It discusses the question of whether individuals with a severe or moderately severe psychiatric disorder have enough cognitive and emotional capacity to weigh reasons for and against ablation or deep brain stimulation and give informed consent to undergo it. The chapter also discusses the obligations of investigators conducting these trials to research subjects. In addition, it examines the medical and ethical justification for a sham control arm in psychiatric neurosurgery clinical trials. It considers the therapeutic potential of optogenetics as a novel form of neuromodulation. The fact that this technique manipulates both genetic material and neural circuits and has been tested only in animal models makes it unclear what its benefit–risk ratio would be. The chapter concludes with a brief discussion of the potential of neuromodulation to stimulate endogenous repair and growth mechanisms in the brain.


Neurosurgery ◽  
2019 ◽  
Author(s):  
Amit Azriel ◽  
Sarah Farrand ◽  
Maria Di Biase ◽  
Andrew Zalesky ◽  
Elaine Lui ◽  
...  

AbstractBACKGROUND AND IMPORTANCEObsessive-compulsive disorder (OCD) is a disabling psychiatric disorder, mainly treated with psychotherapy and pharmacotherapy. Surgical intervention may be appropriate for patients with treatment-refractory OCD. Deep brain stimulation (DBS) is an alternative for previously common ablative surgical procedures. Tractography has been proposed as a method for individualizing DBS treatment and may have the potential to improve efficacy.CLINICAL PRESENTATIONWe present a patient with treatment-refractory OCD previously treated with bilateral leucotomies, who underwent DBS surgery with targeting informed by tractography. Preoperative tractography to identify suitable DBS targets was undertaken. Structural images were also utilized for standard stereotactic surgical planning. The anteromedial globus pallidus internus (amGPi) was chosen as the target bilaterally after consideration of white matter projections to frontal cortical regions and neurosurgical approach. Bilateral amGPi DBS surgery was undertaken without adverse events. At 16-mo follow-up, there was a 48.5% reduction in OCD symptom severity as measured by the Yale-Brown Obsessive Compulsive Scale.CONCLUSIONThe amGPi can be a successful DBS target for OCD. This is the first known case to report on DBS surgery postleucotomies for OCD and highlights the utility of tractography for surgical planning in OCD.


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