The rapid advance of neurotechnology in recent decades comes with enormous potential to find treatments for neurological and psychiatric disorders, but it also raises ethical concerns related to its influence on memory, agency, privacy, the sense of self, and equity among human beings. These considerations have led some researchers to propose establishing "neurorights"—i.e. specific human rights to protect the brain and mental domains—including cognitive liberty, mental integrity, personal identity, and mental privacy, just to name a few [1Ienca M. Andorno R. Towards new human rights in the age of neuroscience and neurotechnology.Life Sci Soc Policy. 2017; 13: 5https://doi.org/10.1186/s40504-017-0050-1Crossref PubMed Scopus (131) Google Scholar, 2Ienca M. On neurorights.Front Hum Neurosci. 2021; 15701258https://doi.org/10.3389/fnhum.2021.701258Crossref PubMed Scopus (15) Google Scholar, 3Yuste R. Goering S. Agüera y Arcas B. Bi G. Carmena J.M. Carter A. Fins J.J. Friesen P. Gallant J. Huggins J.E. Illes J. Kellmeyer P. Klein E. Marblestone A. Mitchell C. Parens E. Pham M. Rubel A. Sadato N. Specker Sullivan L. Teicher M. Wasserman D. Wexler A. Whittaker M. Wolpaw J. Four ethical priorities for neurotechnologies and AI.Nature. 2017; 551: 159-163https://doi.org/10.1038/551159aCrossref PubMed Scopus (156) Google Scholar, 4Goering S. Klein E. Specker Sullivan L. Wexler A. Agüera y Arcas B. Bi G. Carmena J.M. Fins J.J. Friesen P. Gallant J. Huggins J.E. Kellmeyer P. Marblestone A. Mitchell C. Parens E. Pham M. Rubel A. Sadato N. Teicher M. Wasserman D. Whittaker M. Wolpaw J. Yuste R. Recommendations for responsible development and application of neurotechnologies.Neuroethics. 2021; 14: 365-386https://doi.org/10.1007/s12152-021-09468-6Crossref PubMed Scopus (36) Google Scholar], [W1]. Among these rights, the NeuroRights Foundation [W1] and the Neurotechnology Ethics Taskforce [4 (see Recommendation 9)] propose a right to equal access to mental augmentation. Overall, neurorights have given or will eventually give rise to some binding national regulations, namely: an approved constitutional reform in Chile [[W2]Official Journal of the Republic of Chile. Law No. 21,383 - modifies the Fundamental Charter, to establish scientific and technological development at the service of persons. Ministry of the Interior and Public Security of Chile, 2021https://www.diariooficial.interior.gob.cl/edicionelectronica/index.php?date=25-10-2021&edition=43086-B&v=2;Date accessed: April 26, 2023Google Scholar]; Article 19.I of the recent bioethics law in France [[W[3]]Official journal of the French republic. Law No. 2021-1017 of august 2, 2021 relating to bioethics. French Republic, 2021https://www.legifrance.gouv.fr/jorf/article_jo/JORFARTI000043884401;Date accessed: April 26, 2023Google Scholar]; and bills in Argentina [[W[4]]Honorable Chamber of Deputies of the Argentine NationBill No. 0339-D-2022 - modifications about including brain imaging techniques and any other type of neurotechnology as criminal evidence. Argentine Republic, 2022https://www.hcdn.gob.ar/proyectos/proyecto.jsp?exp=0339-D-2022;Date accessed: April 26, 2023Google Scholar], Brazil [[W[5]]Chamber of Deputies of BrazilBill No. 522/2022 - modifies law No. 13.709, of august 14, 2018 (general law for the protection of personal data), in order to conceptualize neural data and regulate its protection. Federative Republic of Brazil, 2022https://www.camara.leg.br/propostas-legislativas/2317524;Date accessed: April 26, 2023Google Scholar], and (again) Chile [[W6]Senate of Chile Bulletin 13828-19 - on the protection of neurorights and mental integrity, and the development of research and neurotechnologies. Republic of Chile, 2020https://www.senado.cl/appsenado/index.php?mo=tramitacion&ac=getDocto&iddocto=14385&tipodoc=mensaje_mocionDate accessed: April 26, 2023https://www.senado.cl/appsenado/templates/tramitacion/index.php?boletin_ini=13828-19);Google Scholar]. Mexico [[W[7]]Personal Data Protection CommissionCharter of rights of the Person in the digital environment. United Mexican States, 2022https://www.infocdmx.org.mx/doctos/2022/Carta_DDigitales.pdf;Date accessed: April 26, 2023Google Scholar] and Spain [[W[7]]Personal Data Protection CommissionCharter of rights of the Person in the digital environment. United Mexican States, 2022https://www.infocdmx.org.mx/doctos/2022/Carta_DDigitales.pdf;Date accessed: April 26, 2023Google Scholar] have also included these rights in their non-binding digital rights charters. Neurorights are an area of interest even for international institutions such as the Latin American Parliament (through a declaration [[W9]Parlatino (Latin American Parliament). Declaration with recommendations on the need to introduce neurorights into the legislation of the Congresses of the member countries, https://parlatino.org/comision-de-seguridad-ciudadana-combate-y-prevencion-al-narcotrafico-terrorismo-y-crimen-organizado/declaracion-neuroderechos/; n.d. [accessed 26 April 2023].Google Scholar] and a model law for their member countries [[W10]Parlatino (Latin American Parliament)Model law on neurorights for Latin America and the caribbean.2023https://parlatino.org/wp-content/uploads/2017/09/leym-neuroderechos-7-3-2023.pdf;Date accessed: April 26, 2023Google Scholar]), the Organization of American States (OAS) (through a declaration [[W11]Inter-American Juridical CommitteeDeclaration CJI/DEC. 01 (XCIX-O/21) on neuroscience, neurotechnologies, and human rights: new legal challenges for the americas. Organization of American States, 2021https://www.oas.org/en/sla/iajc/docs/CJI-DEC_01_XCIX-O-21_ENG.pdf;Date accessed: April 26, 2023Google Scholar] and a draft project of inter-American principles [[W12]Inter-American Juridical CommitteeDevelopment of international standards on neurorights, second progress report: draft inter-American principles on neuroscience, neurotechnologies, and human rights. Organization of American States, 2022https://www.oas.org/en/sla/iajc/docs/CJI-doc_673-22_rev1_ENG.pdf;Date accessed: April 26, 2023Google Scholar]), and the United Nations (through a report by the International Bioethics Committee of UNESCO [[W13]International Bioethics Committee of UNESCOReport "ethical issues of neurotechnology. United Nations, 2022https://unesdoc.unesco.org/ark:/48223/pf0000383559?posInSet=1&queryId=84896d88-79b6-4a07-92a4-82a6352fa98dDate accessed: April 26, 2023Google Scholar] and a resolution by the Human Rights Council [[W14]Human Rights Council Resolution A/HRC/RES/51/3: neurotechnology and human rights. United Nations, 2022https://undocs.org/Home/Mobile?FinalSymbol=A%2FHRC%2FRES%2F51%2F3&Language=E&DeviceType=Desktop&LangRequested=False;Date accessed: April 26, 2023Google Scholar]). Nonetheless, the proposed right to equal access to mental augmentation has received relatively less atention than other neurorights, its presence being limited to the following cases.•Mexico: Chapter VII Section 4 of the Charter of Rights of the Person in the Digital Environment [[8]Mueller S. Wang D. Fox M.D. Thomas Yeo B.T. Sepulcre J. Sabuncu M.R. Shafee R. Lu J. Liu H. Individual variability in functional connectivity architecture of the human brain.Neuron. 2013; 77: 586-595https://doi.org/10.1016/j.neuron.2012.12.028Abstract Full Text Full Text PDF PubMed Scopus (614) Google Scholar].•Spain: Article XXVI.2 of the Charter of Digital Rights [[9]Borbón D. Borbón L. A critical perspective on NeuroRights: comments regarding ethics and law.Front Hum Neurosci. 2021; 15703121https://doi.org/10.3389/fnhum.2021.703121Crossref PubMed Scopus (2) Google Scholar].•Latin American Parliament (Parlatino): Article 5.d of the Model Law on Neurorights for Latin America and the Caribbean [W10]•Organization of American States: Section 4 of the Declaration of the Inter-American Juridical Committee on Neuroscience, Neurotechnologies, and Human Rights [[W[1]]The NeuroRights Foundation. Mission: The five NeuroRights, https://neurorightsfoundation.org/mission; n.d. [accessed 26 April 2023].Google Scholar], and also Principles 5 and 6 of the draft project of Inter-American Principles on Neuroscience, Neurotechnologies, and Human Rights [[W12]Inter-American Juridical CommitteeDevelopment of international standards on neurorights, second progress report: draft inter-American principles on neuroscience, neurotechnologies, and human rights. Organization of American States, 2022https://www.oas.org/en/sla/iajc/docs/CJI-doc_673-22_rev1_ENG.pdf;Date accessed: April 26, 2023Google Scholar]. Neurorights are mostly negative rights, as they compel inaction toward people in the sense of not causing harm, interference, or discrimination. As an exception, the proposed right to equal access to mental augmentation is a positive right, since guaranteeing "equality of access" to cognition-enhancing neurotechnologies [W1]—which include brain stimulation and neuromodulation techniques, both of critical importance for neuroenhancement (NE) [see 5]—would require institutional action in regard to citizens. We clearly recognize and appreciate that the proponents of this neuroright consider it a tool to make neurotechnology inclusive and democratic, ensuring its positive impact on our communities as its use becomes more widespread. Nevertheless, there are noteworthy philosophical, ethico-legal, and socioeconomic challenges that, in our view, discourage establishing a right to equal access to mental augmentation and the active promotion of NE by states and international organizations, at least in the short term. The concept of NE denotes the improvement of healthy brains that have no neurological or psychiatric disorders [[6]Bard I. Gaskell G. Allansdottir A. da Cunha R.V. Eduard P. Hampel J. Hildt E. Hofmaier C. Kronberger N. Laursen S. Meijknecht A. Nordal S. Quintanilha A. Revuelta G. Saladié N. Sándor J. Santos J.B. Seyringer S. Singh I. Somsen H. Toonders W. Torgersen H. Torre V. Varju M. Zwart H. Bottom up ethics - neuroenhancement in education and employment.Neuroethics. 2018; 11: 309-322https://doi.org/10.1007/s12152-018-9366-7Crossref PubMed Scopus (8) Google Scholar], but at the heart of the concept lies a philosophical question: whether enhancing always requires increasing cognitive abilities. Will adding abilities or quantitatively increasing an existing specific ability bring real benefits to individual lives and interpersonal relations between enhanced citizens, or should NE be used for the modification, not the increase, of abilities? This far-from-obvious correspondence between enhancing and increasing also has a cultural dimension as shown, for example, by works that analyze differences in the meaning of neuroenhancement in Spanish and English [[7]Cabrera L.Y. Herrera-Ferrá K. ¿Neuroensanchamiento?: concepts and perspectives about neuroenhancement in the Hispanic literature.J Cogn Enhanc. 2020; 4: 82-93https://doi.org/10.1007/s41465-019-00131-wCrossref Google Scholar]. Ultimately, it becomes necessary to find a common language on NE not only between disciplines but also between cultures. Conceptual consensus is particularly important for transnational and transcultural contexts such as international legal instruments. At the ethical level, the widespread use of NE may threaten neurodiversity, the individual variability in brain functioning among people within the non-pathological spectrum of human cognitive abilities [[8]Mueller S. Wang D. Fox M.D. Thomas Yeo B.T. Sepulcre J. Sabuncu M.R. Shafee R. Lu J. Liu H. Individual variability in functional connectivity architecture of the human brain.Neuron. 2013; 77: 586-595https://doi.org/10.1016/j.neuron.2012.12.028Abstract Full Text Full Text PDF PubMed Scopus (614) Google Scholar]. This is related to the risk of establishing a normality baseline from which to make NEs. It is common (often unavoidable) in neuroscience to deal with data from hundreds or thousands of individuals to obtain an average result, but we should be very skeptical of using averages as a kind of "gold standard" [see W15] by which to neuroenhance someone. Thus, it is crucial to think carefully about how best to create policies for access to NE that are inclusive and respectful of the diversity within and between communities. Another ethical quandary attaches to designing an effective strategy to promote people's voluntary access to mental augmentation without broadening social gaps, a concern recently highlighted by the Organization of American States [W12 (see Principle 6)]. To the extent that NE becomes a widespread practice, it brings the risk that enhanced abilities will become a prototype or standard that generates pressure on citizens about what is desirable, even necessary, if they wish to adapt to society. We should study how we can respect the will of those who do not wish to enhance their abilities without thereby worsening inequalities in cognition, work, culture, society, or the economy. In sum, "States must strive to ensure a balance between private interests and the interests of the community during all phases of the life cycle of neurotechnologies" [[W12]Inter-American Juridical CommitteeDevelopment of international standards on neurorights, second progress report: draft inter-American principles on neuroscience, neurotechnologies, and human rights. Organization of American States, 2022https://www.oas.org/en/sla/iajc/docs/CJI-doc_673-22_rev1_ENG.pdf;Date accessed: April 26, 2023Google Scholar]. There is also another important ethical concern regarding the possibility of secondary and undesirable effects of NE affecting proposed neurorights, for instance personal identity and psychological continuity, since NE may carry the risk of altering people's perceptions of themselves, their personalities, and the world [[9]Borbón D. Borbón L. A critical perspective on NeuroRights: comments regarding ethics and law.Front Hum Neurosci. 2021; 15703121https://doi.org/10.3389/fnhum.2021.703121Crossref PubMed Scopus (2) Google Scholar,[10]Brey P. Human enhancement and personal identity.in: Olsen J.K.B. Selinger E. Riis S. New waves in philosophy of technology. Palgrave Macmillan, London2009: 169-185https://doi.org/10.1057/9780230227279_9Crossref Google Scholar]. For this reason, and to the extent that neurorights' advocates tend to propose incorporating them as a whole, we believe that there is a risk of internal contradiction within their proposal. Socioeconomically, if equal access to NE is established as a positive neuroright, in the sense that states are responsible for guaranteeing equal access, this would inevitably imply a new fiscal burden for already underfunded health systems. For example, Article 10 of bill No. 13828–19 of Chile, which was promoted jointly with the NeuroRights Foundation, expressly establishes that "The State will ensure the promotion and equitable access to advances in neurotechnology and neuroscience" [W6]. Article 13-E of bill No. 522/2022 of Brazil also enunciates that "The State shall take measures to ensure equitable access to advances in neurotechnology" [W5]. Furthermore, according to Principle 6 of the OAS draft project of Inter-American Principles on Neuroscience, Neurotechnologies, and Human Rights, "States must ensure equitable access to treatment using nanotechnological [sic] advances and thus prevent only a few privileged groups from benefiting from advances in science and technology" [[W12]Inter-American Juridical CommitteeDevelopment of international standards on neurorights, second progress report: draft inter-American principles on neuroscience, neurotechnologies, and human rights. Organization of American States, 2022https://www.oas.org/en/sla/iajc/docs/CJI-doc_673-22_rev1_ENG.pdf;Date accessed: April 26, 2023Google Scholar]. It is true that it has also been proposed that neurotechnological companies should be the ones to assume the costs of equitable access for people with lower incomes [[4]Goering S. Klein E. Specker Sullivan L. Wexler A. Agüera y Arcas B. Bi G. Carmena J.M. Fins J.J. Friesen P. Gallant J. Huggins J.E. Kellmeyer P. Marblestone A. Mitchell C. Parens E. Pham M. Rubel A. Sadato N. Teicher M. Wasserman D. Whittaker M. Wolpaw J. Yuste R. Recommendations for responsible development and application of neurotechnologies.Neuroethics. 2021; 14: 365-386https://doi.org/10.1007/s12152-021-09468-6Crossref PubMed Scopus (36) Google Scholar]. However, just as other positive rights such as access to housing, to education, and even to the internet, states would inevitably have to adopt active public policies and allocate a budget for access to NE—even though any of these services could potentially be obtained by a citizen without the help of the state. We believe that governments should not assume unsustainable fiscal obligations to finance neurostimulatory applications (including direct-to-consumer devices, or DTCs) that do not serve the interest of public health and are not medically prescribed [see 11]. Nevertheless, if augmentation is not regulated through international policies and global consensus, the risk is that countries following independent paths will exacerbate the already immense inequalities between countries and populations. The fact that there are important challenges that, in our opinion, discourage actively promoting a positive right to NE does not mean that this practice should be prohibited, as it is worth further research and discussion about its potential benefits. Besides, companies should uphold ethical and safety standards and ensure that the technologies they develop do not affect other rights, such as those to privacy, mental integrity, and personal identity. In this context, the United Nations' guiding principles on business and human rights can be useful, as they insist on (a) states' existing obligations to respect, protect, and fulfill human rights; (b) the duty of enterprises to respect human rights and comply with all applicable laws; and (c) matching rights and obligations with appropriate and effective remedies when rights are breached [[W16]Human Rights Council Resolution A/HRC/RES/17/4: human rights and transnational corporations and other business enterprises. United Nations, 2011https://ap.ohchr.org/documents/dpage_e.aspx?si=A/HRC/RES/17/4Date accessed: April 26, 2023Google Scholar]. In the same vein, the obligation of due diligence implies proactively managing the real and potential risks of neurotechnological applications. Ethics approval was not required for this work. This work did not receive any specific funding.