There is evidence to suggest that some patients who undergo Deep Brain Stimulation can experience changes to dispositional, emotional and behavioural states that play a central role in conceptions of personality, identity, autonomy, authenticity, agency and/or self. For example, some patients undergoing DBS for Parkinson’s Disease have developed hypersexuality, and some have reported increased apathy. Moreover, experimental psychiatric applications of DBS may intentionally seek to elicit changes to the patient’s dispositional, emotional and behavioural states, in so far as dysfunctions in (...) these states may undergird the targeted disorder. Such changes following DBS have been of considerable interest to ethicists, but there is a considerable degree of conflict amongst different parties to this debate about whether DBS really does change PIAAAS, and whether this matters. This paper explores these conflicting views and suggests that we may be able to mediate this conflict by attending more closely to what parties to the debate mean when they invoke the concepts lumped together under the acronym PIAAAS. Drawing on empirical work on patient attitudes, this paper outlines how these different understandings of the concepts incorporated into PIAAAS have been understood in this debate, and how they may relate to other fundamental concepts in medical ethics such as well-being and autonomy. The paper clarifies some key areas of disagreement in this context, and develops proposals for how ethicists might fruitfully contribute to future empirical assessments of apparent changes to PIAAAS following DBS treatment. (shrink)

The profound changes in personality, mood, and other features of the self that neural interventions can induce can be disconcerting to patients, their families, and caregivers. In the neuroethical debate, these concerns are often addressed in the context of possible threats to the narrative self. In this paper, I argue that it is necessary to consider a dimension of impacts on the narrative self which has so far been neglected: neural interventions can lead to a loss of meaning of actions, (...) feelings, beliefs, and other intentional elements of our self-narratives. To uphold the coherence of the self-narrative, the changes induced by neural interventions need to be accounted for through explanations in intentional or biochemical terms. However, only an explanation including intentional states delivers the content to directly ascribe personal meaning, i.e., subjective value to events. Neural interventions can deprive events of meaning because they may favor a predominantly biochemical account. A loss of meaning is not inherently negative but it can be problematic, particularly if events are affected one was not prepared or willing to have stripped of meaning. The paper further examines what it is about neural interventions that impacts meaning by analyzing different methods. To which degree the pull towards a biochemical view occurs depends on the characteristics of the neural intervention. By comparing Deep Brain Stimulation, Prozac, Ritalin, psychedelics, and psychotherapy, the paper identifies some main factors: the rate of change, the transparency of the causal chain, the involvement of the patient, and the presence of an acute phenomenological experience. (shrink)

Deep brain stimulation has been regarded as an efficient and safe treatment for Parkinson’s disease since being approved by the Food and Drug Administration in 1997. It is estimated that more than 150 000 patients have been implanted, with a forecasted rapid increase in uptake with population ageing. Recent longitudinal follow-up studies have reported a significant increase in postoperative survival rates of patients with PD implanted with DBS as compared with those not implanted with DBS. Although DBS tends to increase (...) life expectancy for most patients with PD, this medical benefit does not come without attendant negative consequences. For example, emerging forms of iatrogenic harms are sometimes induced—harms which were not initially expected when clinicians proposed neurosurgery and patients or their guardians consented to the treatment. We report and discuss the clinical case of a patient who was implanted with DBS more than 20 years ago and is now experiencing unexpected stages of PD. This case illustrates how extending the life span without improving quality of life may introduce a burden of harms for patients and families. As well, this case shows why we should prepare for the expanding numbers of PD-implanted patients experiencing a gain of longevity but with severe stages of disease leading to diminution in quality of life. This newly observed effect of DBS treatment requires us to explore ethical questions related to iatrogenic harms, informed consent, end of life and caregivers’ burden. (shrink)

To conclude that there is enough or not enough evidence demonstrating that deep brain stimulation causes unintended postoperative personality changes is an epistemic problem that should be answered on the basis of established, replicable, and valid data. If prospective DBS recipients delay or refuse to be implanted because they are afraid of suffering from personality changes following DBS, and their fears are based on unsubstantiated claims made in the neuroethics literature, then researchers making these claims bear great responsibility for prospective (...) recipients' medical decisions and subsequent well-being. Our article “Deflating the ‘DBS causes personality’ bubble” reported an increase in theoretical neuroethics publications suggesting putative DBS-induced changes to personality, identity, agency, autonomy, authenticity and/or self and a critical lack of supporting primary empirical studies. This special issue of Neuroethics brings together responses to our initial publication, with our own counter-responses organized according to common themes. We provide a brief summary for each commentary and its main criticisms as well as a discussion of the way in which these responses can: 1) help clarify the meaning of PIAAAS, suggesting supplementary frameworks for understanding the impact of DBS on PIAAAS; 2) provide further empirical evidence of PIAAAS by presenting results from the researchers’ own work; and/or 3) offer a critique of our research approach and/or findings. Unintended postoperative putative changes to PIAAAS remain a critical ethical concern. It is beyond dispute that we need to develop reliable empirical and conceptual instruments able to measure complex cognitive, affective, and behavioural changes in order to investigate whether they are attributable to DBS alone. (shrink)