Brain Topography

, Volume 27, Issue 1, pp 33–45 | Cite as

Ethics of the Electrified Mind: Defining Issues and Perspectives on the Principled Use of Brain Stimulation in Medical Research and Clinical Care

  • Laura Y. Cabrera
  • Emily L. Evans
  • Roy H. HamiltonEmail author
Original Paper


In recent years, non-pharmacologic approaches to modifying human neural activity have gained increasing attention. One of these approaches is brain stimulation, which involves either the direct application of electrical current to structures in the nervous system or the indirect application of current by means of electromagnetic induction. Interventions that manipulate the brain have generally been regarded as having both the potential to alleviate devastating brain-related conditions and the capacity to create unforeseen and unwanted consequences. Hence, although brain stimulation techniques offer considerable benefits to society, they also raise a number of ethical concerns. In this paper we will address various dilemmas related to brain stimulation in the context of clinical practice and biomedical research. We will survey current work involving deep brain stimulation, transcranial magnetic stimulation and transcranial direct current stimulation. We will reflect upon relevant similarities and differences between them, and consider some potentially problematic issues that may arise within the framework of established principles of medical ethics: nonmaleficence and beneficence, autonomy, and justice.


Neuroethics Medical ethics Brain stimulation Deep brain stimulation Transcranial direct current stimulation Transcranial magnetic stimulation 


  1. Anderson RJ, Frye MA, Abulseoud OA, Lee KH, McGillivray J, Berk M, Tye SJ (2012) Deep brain stimulation for treatment-resistant depression: efficacy, safety and mechanisms of action. Neurosci Biobehav Rev. doi: 10.1016/j.neubiorev.2012.06.001 PubMedCentralGoogle Scholar
  2. Appelbaum PS (2007) Assessment of patients’ competence to consent to treatment. N Engl J Med 357:1834–1840PubMedCrossRefGoogle Scholar
  3. Appelbaum PS, Grisso T (1998) Assessing patients’ capacities to consent to treatment. N Engl J Med 319(25):1635–1638CrossRefGoogle Scholar
  4. Baylis F (2011) “I Am Who I Am”: on the perceived threats to personal identity from deep brain stimulation. Neuroethics. doi: 10.1007/s12152-011-9137-1 PubMedCentralPubMedGoogle Scholar
  5. Beauchamp PTL, Childress JF (2001) Principles of biomedical ethics. Oxford University Press, OxfordGoogle Scholar
  6. Bell E, Mathieu G, Racine E (2009) Preparing the ethical future of deep brain stimulation. Surg Neurol 72(6):577–586. doi: 10.1016/j.surneu.2009.03.029 PubMedCrossRefGoogle Scholar
  7. Blomstedt P, Hariz MI (2005) Hardware-related complications of deep brain stimulation: a ten year experience. Acta Neurochir 147(10):1061–1064. doi: 10.1007/s00701-005-0576-5 (discussion 1064)PubMedCrossRefGoogle Scholar
  8. Boggio PS, Ferrucci R, Rigonatti SP, Covre P, Nitsche M, Pascual-Leone A, Fregni F (2006) Effects of transcranial direct current stimulation on working memory in patients with Parkinson's disease. J Neurol Sci 249(1):31–38.PubMedCrossRefGoogle Scholar
  9. Brunoni AR, Ferrucci R, Fregni F, Boggio PS, Priori A (2012a) Transcranial direct current stimulation for the treatment of major depressive disorder: a summary of preclinical, clinical and translational findings. Prog Neuro-Psychop 39(1):9–16. doi: 10.1016/j.pnpbp.2012.05.016 CrossRefGoogle Scholar
  10. Brunoni AR, Nitsche MA, Bolognini N, Bikson M, Wagner T, Merabet L, Edwards DJ, Valero-Cabre A, Rotenberg A, Pascual-Leone A, Ferrucci R, Priori A, Boggio PS, Fregni F (2012b) Clinical research with transcranial direct current stimulation (tDCS): challenges and future directions. Brain Stimul 5(3):175–195PubMedCentralPubMedCrossRefGoogle Scholar
  11. Brunoni AR, Valiengo L, Zanao T, Baccaro A, de Oliveoira J, Goulart A, Boggio P et al (2013) The sertraline vs electrical current therapy for treating depression clinical study. JAMA Psychiatry (online first). doi: 10.1001/2013.jamapsychiatry.32 Google Scholar
  12. Bublitz JC, Merkel R (2009) Autonomy and authenticity of enhanced personality traits. Bioethics 23(6):360–374. doi: 10.1111/j.1467-8519.2009.01725.x PubMedCrossRefGoogle Scholar
  13. Cabrera L (2011) They might retain capacities to consent but do they even care? AJOB Neurosci 2(1):41–42. doi: 10.1080/21507740.2010.537300 CrossRefGoogle Scholar
  14. Cohen Kadosh R, Soskic S, Iuculano T, Kanai R, Walsh V (2010) Modulating neuronal activity produces specific and long-lasting changes in numerical competence. Curr Biol 20(22):2016–2020. doi: 10.1016/j.cub.2010.10.007 PubMedCentralPubMedCrossRefGoogle Scholar
  15. Datta A, Elwassif M, Battaglia F, Bikson M (2008) Transcranial current stimulation focality using disc and ring electrode configurations: FEM analysis. J Neural Eng 5(2):163–174PubMedCrossRefGoogle Scholar
  16. Dunn LB, Nowrangi MA, Palmer BW, Jeste DV, Saks ER (2006) Assessing decisional capacity for clinical research or treatment: a review of instruments. Am J Psychiatry 163:1323–1334PubMedCrossRefGoogle Scholar
  17. Farah MJ (2010) Neuroethics: an introduction with readings. Basic bioethics. MIT Press, CambridgeGoogle Scholar
  18. Farah MJ, Wolpe PR (2004) Monitoring and manipulating brain function: new neuroscience technologies and their ethical implications. Hastings Cent Rep 34(3):35–45PubMedCrossRefGoogle Scholar
  19. Fregni F, Pascual-Leone A (2007) Technology Insight: noninvasive brain stimulation in neurology-perspectives on the therapeutic potential of rTMS and tDCS. Nat Clin Pract Neurol 3(7):383–393PubMedCrossRefGoogle Scholar
  20. Fregni F, Boggio PS, Nitsche M, Bermpohl F, Antal A, Feredoes E, Marcolin MA, Rigonatti SP, Silva MT, Paulus W, Pascual-Leone A (2005) Anodal transcranial direct current stimulation of prefrontal cortex enhances working memory. Exp Brain Res 166(1):23–30. doi: 10.1007/s00221-005-2334-6 PubMedCrossRefGoogle Scholar
  21. Fumagalli M, Vergari M, Pasqualetti P, Marceglia S, Mameli F, Ferrucci R, Mrakic-Sposta S, Zago S, Sartori G, Pravettoni G, Barbieri S, Cappa S, Priori A (2010) Brain switches utilitarian behavior: Does gender make the difference? PLoS ONE 5(1):e8865. doi: 10.1371/journal.pone.0008865 PubMedCentralPubMedCrossRefGoogle Scholar
  22. Gandiga PC, Hummel FC, Cohen LG (2006) Transcranial DC stimulation (tDCS): a tool for double-blind sham-controlled clinical studies in brain stimulation. Clin Neurophysiol 117(4):845–850. doi: 10.1016/j.clinph.2005.12.003 PubMedCrossRefGoogle Scholar
  23. George MS, Padberg F, Schlaepfer TE, O’Reardon JP, Fitzgerald PB, Nahas ZH, Marcolin MA (2009) Controversy: repetitive transcranial magnetic stimulation or transcranial direct current stimulation shows efficacy in treating psychiatric diseases (depression, mania, schizophrenia, obsessive-complusive disorder, panic, posttraumatic stress disorder). Brain Stimul 2(1):14–21. doi: 10.1016/j.brs.2008.06.001 PubMedCrossRefGoogle Scholar
  24. Gilbert F (2012) The burden of normality: from ‘chronically ill’ to ‘symptom free’. New ethical challenges for deep brain stimulation postoperative treatment. J Med Ethics 38(7):408–412. doi: 10.1136/medethics-2011-100044 PubMedCrossRefGoogle Scholar
  25. Glannon W (2007) Bioethics and the brain. Oxford University Press, Oxford, New YorkGoogle Scholar
  26. Groppa S, Oliviero A, Eisen A, Quartarone A, Cohen LG, Mall V, Kaelin-Lang A, Mima T, Rossi S, Thickbroom GW, Rossini PM, Ziemann U, Valls-Solé J, Siebner HR (2012) A practical guide to diagnostic transcranial magnetic stimulation: report of an IFCN committee. Clin Neurophysiol 123(5):858–882. doi: 10.1016/j.clinph.2012.01.010 PubMedCrossRefGoogle Scholar
  27. Guller Y, Ferrarelli F, Shackman AJ, Sarasso S, Peterson MJ, Langheim FJ, Meyerand ME, Tononi G, Postle BR (2012) Probing thalamic integrity in schizophrenia using concurrent transcranial magnetic stimulation and functional magnetic resonance imaging. Arch Gen Psychiatry. doi: 10.1001/archgenpsychiatry.2012.23 Google Scholar
  28. Haffen E, Chopard G, Pretalli JB, Magnin E, Nicolier M, Monnin J, Galmiche J, Rumbach L, Pazart L, Sechter D, Vandel P (2012) A case report of daily left prefrontal repetitive transcranial magnetic stimulation (rTMS) as an adjunctive treatment for Alzheimer disease. Brain Stimul 5(3):264–266. doi: 10.1016/j.brs.2011.03.003 PubMedCrossRefGoogle Scholar
  29. Hamilton R, Messing S, Chatterjee A (2011) Rethinking the thinking cap: ethics of neural enhancement using noninvasive brain stimulation. Neurology 76(2):187–193. doi: 10.1212/WNL.0b013e318205d50d PubMedCrossRefGoogle Scholar
  30. Hecht D (2010) Transcranial direct current stimulation in the treatment of anorexia. Med Hypotheses 74(6):1044–1047. doi: 10.1016/j.mehy.2009.12.032 PubMedCrossRefGoogle Scholar
  31. Heinrichs J-H (2012) The promises and perils of non-invasive brain stimulation. Int J Law Psychiatry 35(2):121–129. doi: 10.1016/j.ijlp.2011.12.006 PubMedCrossRefGoogle Scholar
  32. Heldmann M, Berding G, Voges J, Bogerts B, Galazky I, Muller U, Baillot G, Heinze HJ, Munte TF (2012) Deep brain stimulation of nucleus accumbens region in alcoholism affects reward processing. PLoS ONE 7(5):e36572. doi: 10.1371/journal.pone.0036572 PubMedCentralPubMedCrossRefGoogle Scholar
  33. Jotterand F, Giordano J (2011) Transcranial magnetic stimulation, deep brain stimulation and personal identity: ethical questions, and neuroethical approaches for medical practice. Int Rev Psychiatry 23(5):476–485. doi: 10.3109/09540261.2011.616189 PubMedCrossRefGoogle Scholar
  34. Klaming L, Haselager P (2010) Did my brain implant make me do it? Questions raised by DBS regarding psychological continuity, responsibility for action and mental competence. Neuroethics. doi: 10.1007/s12152-010-9093-1 PubMedCentralPubMedGoogle Scholar
  35. Korchounov A, Ziemann U (2011) Neuromodulatory neurotransmitters influence LTP-like plasticity in human cortex: a pharmaco-TMS study. Neuropsychopharmacology 36(9):1894–1902. doi: 10.1038/npp.2011.75 PubMedCrossRefGoogle Scholar
  36. Kramer PD (1994) Listening to prozac. Fourth Estate, LondonGoogle Scholar
  37. Kuhn J, Gaebel W, Klosterkoetter J, Woopen C (2009) Deep brain stimulation as a new therapeutic approach in therapy-resistant mental disorders: ethical aspects of investigational treatment. Eur Arch Psychiatry Clin Neurosci 259(Suppl 2):S135–S141. doi: 10.1007/s00406-009-0055-8 PubMedCrossRefGoogle Scholar
  38. Laxton AW, Tang-Wai DF, McAndrews MP, Zumsteg D, Wennberg R, Keren R, Wherrett J, Naglie G, Hamani C, Smith GS, Lozano AM (2010) A phase I trial of deep brain stimulation of memory circuits in Alzheimer’s disease. Ann Neurol 68(4):521–534. doi: 10.1002/ana.22089 PubMedCrossRefGoogle Scholar
  39. Levy N (2007) Neuroethics. Cambridge University Press, Cambridge, New YorkCrossRefGoogle Scholar
  40. Lipsman N, Glannon W (2012) Brain, mind and machine: What are the implications of deep brain stimulation for perceptions of personal identity, agency and free will? Bioethics. doi: 10.1111/j.1467-8519.2012.01978.x PubMedGoogle Scholar
  41. Lozano AM, Dostrovsky J, Chen R, Ashby P (2002) Deep brain stimulation for Parkinson’s disease: disrupting the disruption. Lancet Neurol 1(4):225–231PubMedCrossRefGoogle Scholar
  42. Marsden DC, Earnst KS, Jamil F, Barolucci A, Harrell L (2000) Consistency of physicians’ legal standard and personal judgments of competency in patients with Alzheimer’s disease. J Am Geriatr Soc 48:911–918Google Scholar
  43. Mathews DJ (2011) Deep brain stimulation, personal identity and policy. Int Rev Psychiatry 23(5):486–492. doi: 10.3109/09540261.2011.632624 PubMedCrossRefGoogle Scholar
  44. Mayberg HS, Lozano AM, Voon V, McNeely HE, Seminowicz D, Hamani C, Schwalb JM, Kennedy SH (2005) Deep brain stimulation for treatment-resistant depression. Neuron 45(5):651–660. doi: 10.1016/j.neuron.2005.02.014 PubMedCrossRefGoogle Scholar
  45. Merkel R, Boer G, Fegert J, Galert T, Hartmann D, Nuttin B, Rosahl S (2007) Intervening in the brain: changing psyche and society. Springer, New YorkGoogle Scholar
  46. Morgan JC, diDonato CJ, Iyer SS, Jenkins PD, Smith JR, Sethi KD (2006) Self-stimulatory behavior associated with deep brain stimulation in Parkinson’s disease. Mov Disord 21(2):283–285. doi: 10.1002/mds.20772 PubMedCrossRefGoogle Scholar
  47. Nitsche MA, Paulus W (2001) Sustained excitability elevations induced by transcranial DC motro cortex stimulation in humans. Neurology 57:1899–1901PubMedCrossRefGoogle Scholar
  48. Nitsche MA, Fricke K, Henschke U, Schlitterlau A, Liebetanz D, Lang N et al (2003) Pharmacological modulation of cortical excitability shifts induced by transcranial direct current stimulation in humans. J Physiol 553(1):293–301PubMedCrossRefGoogle Scholar
  49. Nitsche MA, Seeber A, Frommann K, Klein CC, Rochford C, Nitsche MS, Fricke K, Liebetanz D, Lang N, Antal A, Paulus W (2005) Modulating parameters of excitability during and after transcranial direct current stimulation of the human motor cortex. J Physiol 568(1):291–303PubMedCrossRefGoogle Scholar
  50. Nitsche MA, Doemkes S, Karaköse T, Antal A, Liebetanz D, Lang N, Tergau F, Paulus W (2007) Shaping the effect of transcranial direct current stimulation of the human motor cortex. J Neurophysiol 97:3109–3117PubMedCrossRefGoogle Scholar
  51. Nitsche MA, Cohen LG, Wassermann EM, Priori A, Lang N, Antal A, Paulus W, Hummel F, Boggio PS, Fregni F, Pascual-Leone A (2008) Transcranial direct current stimulation: state of the art. Brain Stimul 1(3):206–223. doi: 10.1016/j.brs.2008.06.004 PubMedCrossRefGoogle Scholar
  52. Palm U, Keeser D, Fintescu C, Reisinger M, Nitsche M, Padberg F (2008) Skin lesions after treatment with transcranial direct current stimulation (tDCS). Brain Stimul 1:386–387PubMedCrossRefGoogle Scholar
  53. Pascual-Leone A, Wagner T (2007) A brief summary of the history of noninvasive brain stimulation. Annu Rev Biomed Eng 9:527–565PubMedCrossRefGoogle Scholar
  54. Pascual-Leone A, Bartres-Faz D, Keenan JP (1999a) Transcranial magnetic stimulation: studying the brain-behaviour relationship by induction of ‘virtual lesions’. Philos Trans R Soc Lond B Biol Sci 354(1387):1229–1238. doi: 10.1098/rstb.1999.0476 PubMedCrossRefGoogle Scholar
  55. Pascual-Leone A et al (1999b) Transcranial magneticstimulation and neuroplasticity. Neuropsychologia 37:207–217PubMedCrossRefGoogle Scholar
  56. Pascual-Leone A, Fregni F, Steven-Wheeler, Forrow L (2011) Non-invasive brain stimulation as a therapeutic and investigative tool: an ethical appraisal. In: Illes J, Sahakian BJ (eds) Oxford handbook of neuroethics. Oxford University Press, New York, pp 417–439Google Scholar
  57. Ponce FA, Lozano AM (2010) Deep brain stimulation state of the art and novel stimulation targets. Prog Brain Re 184:311–324. doi: 10.1016/S0079-6123(10)84016-6 CrossRefGoogle Scholar
  58. Poreisz C, Boros K, Antal A, Paulus W (2007) Safety aspects of transcranial direct current stimulation concerning healthy subjects and patients. Brain Res Bull 72:208–214PubMedCrossRefGoogle Scholar
  59. Priori A (2003) Brain polarization in humans: a reappraisal of an old tool for prolonged non-invasive modulation of brain excitability. Clin Neurophysiol 114(4):589–595. doi: 10.1016/s1388-2457(02)00437-6 PubMedCrossRefGoogle Scholar
  60. Priori A, Hallett M, Rothwell JC (2009) Repetitive transcranial magnetic stimulation or transcranial direct current stimulation? Brain Stimul 2(4):241–245. doi: 10.1016/j.brs.2009.02.004 PubMedCrossRefGoogle Scholar
  61. Racine E (2010) Pragmatic neuroethics: improving treatment and understanding of the mind-brain. Basic bioethics. MIT Press, CambridgeGoogle Scholar
  62. Rossi S, Hallett M, Rossini PM, Pascual-Leone A (2009) Safety, ethical considerations, and application guidelines for the use of transcranial magnetic stimulation in clinical practice and research. Clin Neurophysiol 120(12):2008–2039PubMedCentralPubMedCrossRefGoogle Scholar
  63. Sampson SM, Kung S, McAlpine DE, Sandroni P (2011) The use of slow-frequency prefrontal repetitive transcranial magnetic stimulation in refractory neuropathic pain. J ECT 27(1):33–37. doi: 10.1097/YCT.0b013e31820c6270 PubMedCrossRefGoogle Scholar
  64. Schlaug G, Renga V, Nair D (2008) Transcranial direct current stimulation in stroke recovery. Arch Neurol 65(12):1571–1576. doi: 10.1001/archneur.65.12.1571 PubMedCentralPubMedCrossRefGoogle Scholar
  65. Schmitz-Luhn B, Katzenmeier C, Woopen C (2012) Law and ethics of deep brain stimulation. Int J Law Psychiatry 35(2):130–136. doi: 10.1016/j.ijlp.2011.12.007 PubMedCrossRefGoogle Scholar
  66. Sims JM (2010) A brief review of the Belmont report. Dimens Crit Care Nurs 29(4):173–174. doi: 10.1097/DCC.0b013e3181de9ec5 PubMedCrossRefGoogle Scholar
  67. Synofzik M, Schlaepfer TE (2011) Electrodes in the brain: ethical criteria for research and treatment with deep brain stimulation for neuropsychiatric disorders. Brain Stimul 4(1):7–16. doi: 10.1016/j.brs.2010.03.002 PubMedCrossRefGoogle Scholar
  68. Temel Y, Kessels A, Tan S, Topdag A, Boon P, Visser-Vandewalle V (2006) Behavioural changes after bilateral subthalamic stimulation in advanced Parkinson disease: a systematic review. Parkinsonism Relat Disord 12(5):265–272. doi: 10.1016/j.parkreldis.2006.01.004 PubMedCrossRefGoogle Scholar
  69. UNC School of Medicine (2012) Deep brain stimulation—DBS. Accessed 7 Oct 2012Google Scholar
  70. Valldeoriola F (2011). Cost and efficacy of therapies for advanced parkinson’s disease. In: Finkelstein (ed) Towards new therapies for parkinson’s disease. InTech, doi: 10.5772/17862. Available from
  71. Valldeoriola F, Morsi O, Tolosa E et al (2007) Prospective comparative study on cost-effectiveness of subthalamic stimulation and best medical treatment in advanced Parkinson’s disease. Mov Disord 22:2183–2191PubMedCrossRefGoogle Scholar
  72. Wagner T, Valero-Cabre A, Pascual-Leone A (2007) Noninvasive human brain stimulation. Annu Rev Biomed Eng 9:527–565. doi: 10.1146/annurev.bioeng.9.061206.133100 PubMedCrossRefGoogle Scholar
  73. Wassermann EM (1998) Risk and safety of repetitive transcranial magnetic stimulation: report and suggested guidelines from the international workshop on the safety of repetitive transcranial magnetic stimulation, June 5–7, 1996. Electroencephalogr Clin Neurophysiol 108(1):1–16PubMedCrossRefGoogle Scholar
  74. Witt K, Kuhn J, Timmermann L, Zurowski M, Woopen C (2011) Deep brain stimulation and the search for identity. Neuroethics. doi: 10.1007/s12152-011-9100-1 PubMedCentralPubMedGoogle Scholar
  75. World Medical Association General Assembly (2001) World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects (revised October 7, 2000). HIV Clin Trials 2001 2 [Jan-Feb (1)]:92–95Google Scholar
  76. Wu CC, Tsai CH, Lu MK, Chen CM, Shen WC, Su KP (2010) Theta-burst repetitive transcranial magnetic stimulation for treatment-resistant obsessive-compulsive disorder with concomitant depression. J Clin Psychiatry 71(4):504–506. doi: 10.4088/JCP.09l05426blu PubMedCrossRefGoogle Scholar
  77. Wu H, Van Dyck-Lippens PJ, Santegoeds R, van Kuyck K, Gabriels L, Lin G, Pan G, Li Y, Li D, Zhan S, Sun B, Nuttin B (2012) Deep-brain stimulation for anorexia nervosa. World Neurosurg. doi: 10.1016/j.wneu.2012.06.039 Google Scholar

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Laura Y. Cabrera
    • 1
  • Emily L. Evans
    • 2
  • Roy H. Hamilton
    • 2
    • 3
    Email author
  1. 1.National Core for NeuroethicsThe University of British ColumbiaVancouverCanada
  2. 2.Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUSA
  3. 3.Laboratory for Cognition and Neural Stimulation, Department of NeurologyUniversity of PennsylvaniaPhiladelphiaUSA

Personalised recommendations