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Transplantation
Published in Stephen W. Carmichael, Susan L. Stoddard, The Adrenal Medulla 1986 - 1988, 2017
Stephen W. Carmichael, Susan L. Stoddard
Much of the earlier work on transplantation of the adrenal medulla in animal models was reviewed by Olson, Backlund, Freed et al. (1985). This review stressed experiments directed toward a treatment for Parkinson’s disease. Papers from a meeting on cell and tissue transplantation into the adult brain were assembled by Azmitia and Björklund (1987a). They also published a summary of this meeting (Azmitia and Björklund, 1987b). Björklund, Lindvall, Isacson et al. (1987) reviewed the mechanisms of action of intracerebral neural implants, focusing on how implants exert their functional effects. A brief review of studies in lower animals that indicate a future for brain implants was published by Friedman (1986).
Advanced Optical Imaging in the Study of Acute and Chronic Response to Implanted Neural Interfaces
Published in Yu Chen, Babak Kateb, Neurophotonics and Brain Mapping, 2017
Cristin G. Welle, Daniel X. Hammer
The expanded use of in vivo imaging modalities in the context of neural interface devices can address key questions with regard to device safety and effectiveness through direct observation of experimental manipulation. For example, the degree of cellular atrophy, particularly for neurons, in very close proximity to the electrode has been debated in literature. This question is difficult to answer with histology due to tissue disruption inherent to the technique, but can be easily addressed with chronic, in vivo imaging of regions surrounding a brain implant. Other questions that could be answered with in vivo imaging techniques include the timing of the neuroinflammatory response, particularly with respect to microglia and astrocytes, and the correlation of the tissue response with the observed decline of high-quality electrophysiological signals. In addition, the changes in vascularization and blood flow dynamics over time and with respect to different electrode morphologies can be meaningfully investigated with these techniques. Understanding cellular atrophy, neuroinflammation, hypoxia and vascular remodeling, and the correlation with device parameters and performance can provide the insights needed to dramatically improve neural interface performance, and bring the next-generation technology to benefit patients in need of neurological or psychiatric intervention.
Brain Implants
Published in L. Syd M Johnson, Karen S. Rommelfanger, The Routledge Handbook of Neuroethics, 2017
Modulating dysfunctional neural circuits with DBS, bypassing them with BCIs or replacing them with HPs does not undermine but can restore the motor and mental capacities that constitute free will. Provided that these brain implants enable people with brain injuries or neuropsychiatric disorders to reason and make decisions in accord with their considered desires and values, they can identify the mechanisms associated with these devices as their own. The devices can be experienced by those in whom they are implanted as forms of extended or expanded embodiment (Lebedev, 2014). DBS can restore a greater degree of behavior control than BCIs or HPs. This is not only because it can modulate a broader range of motor and mental functions but also because persons in whom a DBS system is implanted can turn the stimulator on or off. This may make the agent responsible for later actions when he is behaviorally impaired if he has the capacity to foresee this impairment as the possible consequence of his earlier action. Restoration of motor functions or communication in BCIs is more limited because severe and prolonged paralysis may impair the cognitive and volitional capacities necessary to operate the system. The success or failure of a person’s attempt to operate a BCI may depend on her interaction with the practitioner training her. HPs can restore agency by enabling the learning of information associated with memory that is necessary to form and carry out action plans. This ability will depend also on the meaning the subject assigns to long-term episodic memory and his experience of moving through space and time. With BCIs and HPs, factors inside and outside the brain can influence whether or to what extent a person regains and can exercise free will.
“They Are Invasive in Different Ways.”: Stakeholders’ Perceptions of the Invasiveness of Psychiatric Electroceutical Interventions
Published in AJOB Neuroscience, 2023
Robyn Bluhm, Marissa Cortright, Eric D. Achtyes, Laura Y. Cabrera
In this paper, we draw on data from a series of interviews in order to develop a preliminary account of how the invasiveness of medical neurotechnologies is perceived by psychiatrists, patients, and members of the public. The results discussed here are part of a larger project on the ethics of psychiatric electroceutical interventions (PEIs)—therapeutic interventions that use electricity to modulate neural activity—as treatments for major depressive disorder (MDD). The focus of this larger project is on MDD because a variety of PEIs are in use or in development for its treatment. The PEIs investigated in this project are ECT, repetitive transcranial magnetic stimulation (rTMS), DBS, and adaptive brain implants (ABI), all of which are used or proposed as treatments for depression. Two of these (DBS and ABIs) count as invasive according to the standard medical definition, because they involve both surgery and the use of a neural implant. Two (ECT and rTMS) are not considered to be invasive on this definition; they affect neural activity but do not involve cutting or inserting an object into the body. In this paper, we aimed to investigate whether our participants’ views of invasiveness reflect the standard view in medicine (which is largely assumed by neuroethicists) and to understand what factors shape these perceptions of invasiveness.
Brain Device Research and the Underappreciated Role of Care Partners before, during, and Post-Trial
Published in AJOB Neuroscience, 2022
Amanda R. Merner, Joseph J. Fins, Gabriel Lázaro-Muñoz
The number of clinical trials for experimental brain implants continues to grow, and with this growth comes an increased reliance upon patients with treatment-refractory conditions to volunteer as participants in these studies. Sankary et al. (2022) provided insight into participants’ experiences exiting brain device trials, a topic of great interest in neuroethics (Fins 2009; Lázaro-Muñoz et al. 2018, 2022). However, the burdens associated with trial participation trials are not limited solely to participants. The demands of device trials and severity of the conditions being treated often require that participants have dedicated care partners—typically a family member or close friend—who assist with research-related decision-making and adherence to study protocols, while also providing day-to-day care and support to participants. Despite their important role in research efforts, little is known about care partner perspectives and experiences before, during, and after brain device trials. Sankary et al. (2022) provided data from interviews conducted with participants as well as a care partner; however, they did not differentiate between the views of participants1 (n = 15) from those of the care partner (n = 1) included in the study. In contrast, Fins and Wright (2022) have identified differential perceptions of risk by subjects and care partners. Beyond these preliminary studies, it is essential to actively engage care partners and gain insight into their perspectives for three reasons.
Nanomaterials in neuromodulation: what is the potential?
Published in Expert Review of Neurotherapeutics, 2022
Rick Knoben, Faisal Alosaimi, David Dominguez-Paredes, Yasin Temel, Ali Jahanshahi
In summary, the use of nanomaterials as nanoelectrodes shows promise as a new solution for wireless neural devices. As this field is still in its infancy, future research will be critical to understanding the potentials and limitations of this technology. Furthermore, research into noninvasive delivery routes, toxicity, and cell/tissue targeting specificity will help bring this technology closer to clinical application. A substantial number of studies have tested nanomaterials for neuromodulation, but the majority of those have used in vitro or in silico models. The application of these nanomaterials in animal models of neurological and psychiatric disorders will help to clarify the main components driving their therapeutic effect, and the mechanisms that may underlie patient responses. Clarifying these aspects will direct more rational and effective decision-making in translating the use of the nanomaterials to the clinic. To conclude, it is important to recognize that several novel ethical considerations arise when developing brain implants with nano-scale materials. Especially, the excitement regarding the use of innovative nano-scale materials should not be at the cost of compromising patient safety and long-term safety assurances. In this regard, research ethics guidelines will likely require reconsideration to acknowledge these issues [28].