communication. It is possible that more substantial ethics discussion takes place in reviews, policy articles, or grant applications, and future studies could investigate these additional domains. In any case, given the rich discussion within neuroethics, policy debate, and the popular press, the relative lack of ELSI content in the primary literature is somewhat surprising and deserves further investigation. The central topic cluster in our graphical analysis included both moral correlates research, and discussion of the ethics issues associated with using fMRI to putatively reveal facets or contents of the mind – often referred to as mind-reading. In the direct citation analysis we excluded moral correlates research, but several articles included discussion of the neural basis of morality among other ethics issues. We argue that these two domains naturally inform each other: for example, neuroimaging research on phenomena relating to disgust and their possible implications for jury behaviour ostensibly addresses a question about the neural basis of an ethical phenomenon, but does not answer the question of how such knowledge ought to be used [24]. Several scholars have argued that the nature of bioethical enquiry precludes the kind of binary fact- value distinction implied by a separation between research ethics and the neural correlates of ethics [24,60], and we suggest that an emphasis on such distinctions may stymie further debate. Bibliometrics rests on the assumption that authors cite the most appropriate available references, that their literature review is exhaustive, and that chosen citations are objectively valid for the purpose intended. Beyond this assumption, ‘‘authors are free to do whatever they need to the earlier literature to render it as helpful as possible for their own arguments’’ [61]. Citation analysis does not carry any positive or negative polarity, and should not be taken to provide a measure of the quality of a given work. What is actually being tracked is indirect influence, along with a work’s visibility or acceptance among a described community. This is invaluable to the descriptive analysis of the role of terminology in shaping the dissemination and structure of new research fields [62]. Indeed, in tracing the network of research that has shaped neuroethics, we have found threads weaving together from diverse literatures in sociology, anthropology, cognitive psychology, behavioural psychology, marketing, law, and others. Lest we claim to have rediscovered what was not lost, we note that these links often originate in deliberate attempts by researchers working to unite the disciplines. Here, we aim to contextualize these individual links by providing a broader picture of the cross- References 1. Logothetis N (2008) What we can do and what we cannot do with fMRI. Nature 435: 869–878. 2. Farah MJ, Wolpe PR (2004) Monitoring and manipulating brain function: New neuroscience technologies and their ethical implications. Hastings Center Report 34: 35–45. 3. Illes J (2006) Neuroethics: Defining the Issues in Theory, Practice, and Policy. Oxford: Oxford University Press. 4. Farah MJ (2005) Neuroethics: The practical and philosophical. Trends in Cognitive Neurosciences 9: 34–40. 5. Racine E, Illes J (2007) Emerging ethical challenges in advanced neuroimaging research: Review, recommendations and research agenda. Journal of Empirical Research on Human Research Ethics 2: 1–10. 6. Miller FG, Wertheimer A (2010) The Ethics of Consent: Theory and Practice. Oxford: Oxford University Press. 7. Illes J, Kirschen MP, Edwards E, Stanford LR, Bandettini P, et al. 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Through mapping citation patterns we have presented the most complete picture yet of the extension of ethics into published fMRI research, and the locus of fMRI in ethical, legal, and social commentary. We conclude by emphasizing the benefit of devoting at least some space in fMRI research articles to specific research ethics questions, and to discussion of the wider meaning, concrete implications, and conceptual underpinnings of neuroimaging findings. Situating such discussion in the context in which it is originally reported [63] has the potential to improve the dissemination and prominence of ethical discussion surrounding this potent technology, to ground debate about the nature and reach of its real-world implications, and to challenge assumptions of neutrality at every stage of the research process. Supporting Information Appendix S1 (DOC) Author Contributions Conceived and designed the experiments: AG HP ER JI. Performed the experiments: AG HP. Analyzed the data: AG LW ER JI. 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