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- Genre: Masters Thesis
Description
When surgical resection becomes necessary to alleviate a patient's epileptiform activity, that patient is monitored by video synchronized with electrocorticography (ECoG) to determine the type and location of seizure focus. This provides a unique opportunity for researchers to gather neurophysiological data with high temporal and spatial resolution; these data are assessed prior to surgical resection to ensure the preservation of the patient's quality of life, e.g. avoid the removal of brain tissue required for speech processing. Currently considered the "gold standard" for the mapping of cortex, electrical cortical stimulation (ECS) involves the systematic activation of pairs of electrodes to localize functionally specific brain regions. This method has distinct limitations, which often includes pain experienced by the patient. Even in the best cases, the technique suffers from subjective assessments on the parts of both patients and physicians, and high inter- and intra-observer variability. Recent advances have been made as researchers have reported the localization of language areas through several signal processing methodologies, all necessitating patient participation in a controlled experiment. The development of a quantification tool to localize speech areas in which a patient is engaged in an unconstrained interpersonal conversation would eliminate the dependence of biased patient and reviewer input, as well as unnecessary discomfort to the patient. Post-hoc ECoG data were gathered from five patients with intractable epilepsy while each was engaged in a conversation with family members or clinicians. After the data were separated into different speech conditions, the power of each was compared to baseline to determine statistically significant activated electrodes. The results of several analytical methods are presented here. The algorithms did not yield language-specific areas exclusively, as broad activation of statistically significant electrodes was apparent across cortical areas. For one patient, 15 adjacent contacts along superior temporal gyrus (STG) and posterior part of the temporal lobe were determined language-significant through a controlled experiment. The task involved a patient lying in bed listening to repeated words, and yielded statistically significant activations that aligned with those of clinical evaluation. The results of this study do not support the hypothesis that unconstrained conversation may be used to localize areas required for receptive and productive speech, yet suggests a simple listening task may be an adequate alternative to direct cortical stimulation.
ContributorsLingo VanGilder, Jennapher (Author) / Helms Tillery, Stephen I (Thesis advisor) / Wahnoun, Remy (Thesis advisor) / Buneo, Christopher (Committee member) / Arizona State University (Publisher)
Created2013
Description
Neuroimaging has appeared in the courtroom as a type of `evidence' to support claims about whether or not criminals should be held accountable for their crimes. Yet the ability to abstract notions of culpability and criminal behavior with confidence from these imagines is unclear. As there remains much to be discovered in the relationship between personal responsibility, criminal behavior, and neurological abnormalities, questions have been raised toward neuroimaging as an appropriate means to validate these claims.
This project explores the limits and legitimacy of neuroimaging as a means of understanding behavior and culpability in determining appropriate criminal sentencing. It highlights key philosophical issues surrounding the ability to use neuroimaging to support this process, and proposes a method of ensuring their proper use. By engaging case studies and a thought experiment, this project illustrates the circumstances in which neuroimaging may assist in identifying particular characteristics relevant for criminal sentencing.
I argue that it is not a question of whether or not neuroimaging itself holds validity in determining a criminals guilt or motives, but rather a proper application of the issue is to focus on the way in which information regarding these images is communicated from the `expert' scientists to the `non-expert' making decisions about the sentence that are most important. Those who are considering this information's relevance, a judge or jury, are typically not well versed in criminal neuroscience and interpreting the significance of different images. I advocate the way in which this information is communicated from the scientist-informer to the decision-maker parallels in importance to its actual meaning.
As a solution, I engage Roger Pielke's model of honest brokering as a solution to ensure the appropriate use of neuroimaging in determining criminal responsibility and sentencing. A thought experiment follows to highlight the limits of science, engage philosophical repercussions, and illustrate honest brokering as a means of resolution. To achieve this, a hypothetical dialogue reminiscent of Kenneth Schaffner's `tools for talking' with behavioral geneticists and courtroom professionals will exemplify these ideas.
This project explores the limits and legitimacy of neuroimaging as a means of understanding behavior and culpability in determining appropriate criminal sentencing. It highlights key philosophical issues surrounding the ability to use neuroimaging to support this process, and proposes a method of ensuring their proper use. By engaging case studies and a thought experiment, this project illustrates the circumstances in which neuroimaging may assist in identifying particular characteristics relevant for criminal sentencing.
I argue that it is not a question of whether or not neuroimaging itself holds validity in determining a criminals guilt or motives, but rather a proper application of the issue is to focus on the way in which information regarding these images is communicated from the `expert' scientists to the `non-expert' making decisions about the sentence that are most important. Those who are considering this information's relevance, a judge or jury, are typically not well versed in criminal neuroscience and interpreting the significance of different images. I advocate the way in which this information is communicated from the scientist-informer to the decision-maker parallels in importance to its actual meaning.
As a solution, I engage Roger Pielke's model of honest brokering as a solution to ensure the appropriate use of neuroimaging in determining criminal responsibility and sentencing. A thought experiment follows to highlight the limits of science, engage philosophical repercussions, and illustrate honest brokering as a means of resolution. To achieve this, a hypothetical dialogue reminiscent of Kenneth Schaffner's `tools for talking' with behavioral geneticists and courtroom professionals will exemplify these ideas.
ContributorsTaddeo, Sarah (Author) / Robert, Jason S (Thesis advisor) / Marchant, Gary (Committee member) / Hurlbut, James B (Committee member) / Arizona State University (Publisher)
Created2014
Description
The advent of advanced reproductive technologies has sparked a number of ethical concerns regarding the practices of reproductive tourism and commercial gestational surrogacy. In the past few decades, reproductive tourism has become a global industry in which individuals or couples travel, usually across borders, to gain access to reproductive services. This marketable field has expanded commercial gestational surrogacy--defined by a contractual relationship between an intending couple and gestational surrogate in which the surrogate has no genetic tie to fetus--to take on transnational complexities. India has experienced extreme growth due to a preferable combination of western educated doctors and extremely low medical costs. However, a slew of ethical issues have been brought to the forefront: the big ones manifesting as concern for reduction of a woman's worth to her reproductive capabilities along with concern for exploitation of third world women. This project will be based exclusively on literature review and serves primarily as a call for cultural competency and understanding the circumstances that gestational surrogates are faced with before implementing policy regulating commercial gestational surrogacy. The paper argues that issues of exploitation and commodification hinge on constructions of motherhood. It is critical to define and understand definitions of motherhood and how these definitions affect a woman's approach to reproduction within the cultural context of a gestational surrogate. This paper follows the case study of the Akanksha Infertility Clinic in northern India, a surrogacy clinic housing around 50 Indian surrogates. The findings of the project invokes the critical significance of narrative ethics, which help Indian surrogates construct the practice of surrogacy so that it fits into cultural comprehensions of Indian motherhood--in which motherhood is selfless, significant, and shared.
ContributorsMoorthy, Anjali (Author) / Robert, Jason S (Thesis advisor) / Hurlbut, Benjamin (Committee member) / Ellison, Karin (Committee member) / Arizona State University (Publisher)
Created2011
Description
Within ethics, a number of scholars advocate an interdisciplinary approach of combining the two traditionally different professions of science and philosophy with the confidence that this collaboration will be a mutually beneficial experience. Current ethicist-scientist interactions include embedded-ethicists and research ethics consultation services. Both methods are employed with the hope that they will reduce social and ethical problems that could arise from scientific research, and enhance the reflective capacity of investigative teams. While much effort has been put forth in the endeavor of creating ethicist-scientist interactions, there remains opportunity to refine these new interaction models to make them more robust. There is need for ethicists to understand the context of ethical decision-making in the laboratory. By extension, before interacting with scientists in a research lab, research ethicists ought to have the ability to understand the science and also be familiar with the different factors that influence scientific research, such as funding, productivity requirements, time constraints, politics of laboratories and institutional reward structures. Through literature review and the analysis of qualitative data obtained from the ethnographic study in a neuroscience laboratory, this thesis explores the strengths and weaknesses of ethicist-scientist interactions and aims to understand the culture, traditions and values of this community and their perspectives on their role as scientists and their relationship to ethics. This study shows that the quantity and quality of ethics discussions in the lab are limited and dictated by time constraints and minimal incentives. Other influencing factors are the researchers' perspectives on ethics and how they view their role as a scientist in relation to the public.
ContributorsMin, Gyongeun Catherine (Author) / Ellison, Karin (Thesis advisor) / Robert, Jason S (Thesis advisor) / Minteer, Ben A (Committee member) / Arizona State University (Publisher)
Created2012
Description
With new trends in drug development and testing, it must be determined whether the current state of balance of ethos (the moral norm) and regula (the legal framework) can successfully protect patients while keeping the door to scientific innovation open. The rise of the Clinician Investigator (CI) in both academic and private research introduces a challenge to the protection of subjects in the conflicting dual role of physician and scientist. Despite the constant evolution of regulation and ethical standards, questions about the roles' combined effectiveness in relation to this challenge persist. Carl Elliot describes the suicide of a patient-subject enrolled in an industry-funded physician-run anti-psychotic pharmaceutical drug trial in a 2010 Mother Jones article. Elliot provides a personal account of discrepancies seen in the ethical principles of beneficence, respect for subjects and justice. Through analysis of the problems presented in the case as a model for potential dangers in clinical research, the effectiveness of ethics and law in protecting human subjects is examined. While the lag between ethical standard and regulation has historically shown to cause similar issues, the misconception of current regulation and ethical standards may be contributing to the decrease in subject protections. After IRB approval of subject protections in the research protocol, CIs have been shown to downgrade their responsibility to maintaining ethos through the course of the trial. And, despite their experience in patient-centered ethos as a physician, CIs may be inclined to substitute these values for the ethos of a researcher, with the goal to avoid therapeutic misconception. Maintaining personal responsibility for subjects beyond regulatory structure, and promoting the welfare of the subjects in regards to the ethical standard of research investigators, will provide added security for subjects and decrease opportunity for exploitation in future research.
ContributorsWaddell, Amanda (Author) / Robert, Jason S (Thesis advisor) / Ellison, Karin (Committee member) / Fuse Brown, Erin C. (Committee member) / Arizona State University (Publisher)
Created2012
Description
Effective tactile sensing in prosthetic and robotic hands is crucial for improving the functionality of such hands and enhancing the user's experience. Thus, improving the range of tactile sensing capabilities is essential for developing versatile artificial hands. Multimodal tactile sensors called BioTacs, which include a hydrophone and a force electrode array, were used to understand how grip force, contact angle, object texture, and slip direction may be encoded in the sensor data. Findings show that slip induced under conditions of high contact angles and grip forces resulted in significant changes in both AC and DC pressure magnitude and rate of change in pressure. Slip induced under conditions of low contact angles and grip forces resulted in significant changes in the rate of change in electrode impedance. Slip in the distal direction of a precision grip caused significant changes in pressure magnitude and rate of change in pressure, while slip in the radial direction of the wrist caused significant changes in the rate of change in electrode impedance. A strong relationship was established between slip direction and the rate of change in ratios of electrode impedance for radial and ulnar slip relative to the wrist. Consequently, establishing multiple thresholds or establishing a multivariate model may be a useful method for detecting and characterizing slip. Detecting slip for low contact angles could be done by monitoring electrode data, while detecting slip for high contact angles could be done by monitoring pressure data. Predicting slip in the distal direction could be done by monitoring pressure data, while predicting slip in the radial and ulnar directions could be done by monitoring electrode data.
ContributorsHsia, Albert (Author) / Santos, Veronica J (Thesis advisor) / Santello, Marco (Committee member) / Helms Tillery, Stephen I (Committee member) / Arizona State University (Publisher)
Created2012
Description
In the past century, a number of technological projects have been undertaken as grand solutions to social problems. In the so called century of biology, this technological world view focuses on biomedical advances. The President of the United States, who once called for nuclear weapons and space exploration, now calls for new biotechnologies, such as genomics, individualized medicine, and nanotechnology, which will improve the world by improving our biological lives. Portrayed as the Manhattan Project of the late 20th Century, the Human Genome Project (HGP) not only undertook the science of sequencing the human genome but also the ethics of it. For this thesis I ask how the HGP did this; what was the range of possibilities of goods and evils imagined by the HGP; and what, if anything, was left out. I show that the Ethical, Legal, and Social Implications (ELSI) research program of the HGP was inscribed with the competencies of the professional field of bioethics, which had lent itself useful for governing biomedical science and technology earlier in the 20th century. Drawing on a sociological framework for understanding the development of professional bioethics, I describe the development of ELSI, and I note how the given-in-advance boundaries between authorized/unauthorized questions shaped its formation and biased technologically based conceptualizations of social problems and potential solutions. In this sense, the HGP and ELSI served both as the ends of policy and as instruments of self-legitimation, thus re-inscribing and enacting the structures for these powerful sociotechnical imaginaries. I engage the HGP and ELSI through historical, sociological, and political philosophical analysis, by examining their immediate context of the NIH, the meso level of professional/disciplinary bioethics, and the larger context of American democracy and modernity. My argument is simultaneously a claim about how questions are asked and how knowledge and expertise are made, exposing the relationship between the HGP and ELSI as a mutually constitutive and reciprocally related form of coproduction of knowledge and social structures. I finish by arguing that ELSI is in a better position than bioethics to carry out the original project of that field, i.e., to provide a space to elucidate certain institutionally authorized questions about science and technology. Finally, I venture into making a prophecy about the future of ELSI and bioethics: that the former will replace the latter as a locus for only formally rational and thin ethical debates.
ContributorsCarvalho, Tito (Author) / Robert, Jason S (Thesis advisor) / Ellison, Karin D (Committee member) / Hurlbut, James B (Committee member) / Arizona State University (Publisher)
Created2012
Description
In the past decade, research on the motor control side of neuroprosthetics has steadily gained momentum. However, modern research in prosthetic development supplements a focus on motor control with a concentration on sensory feedback. Simulating sensation is a central issue because without sensory capabilities, the sophistication of the most advanced motor control system fails to reach its full potential. This research is an effort toward the development of sensory feedback specifically for neuroprosthetic hands. The present aim of this work is to understand the processing and representation of cutaneous sensation by evaluating performance and neural activity in somatosensory cortex (SI) during a grasp task. A non-human primate (Macaca mulatta) was trained to reach out and grasp textured instrumented objects with a precision grip. Two different textures for the objects were used, 100% cotton cloth and 60-grade sandpaper, and the target object was presented at two different orientations. Of the 167 cells that were isolated for this experiment, only 42 were recorded while the subject executed a few blocks of successful trials for both textures. These latter cells were used in this study's statistical analysis. Of these, 37 units (88%) exhibited statistically significant task related activity. Twenty-two units (52%) exhibited statistically significant tuning to texture, and 16 units (38%) exhibited statistically significant tuning to posture. Ten of the cells (24%) exhibited statistically significant tuning to both texture and posture. These data suggest that single units in somatosensory cortex can encode multiple phenomena such as texture and posture. However, if this information is to be used to provide sensory feedback for a prosthesis, scientists must learn to further parse cortical activity to discover how to induce specific modalities of sensation. Future experiments should therefore be developed that probe more variables and that more systematically and comprehensively scan somatosensory cortex. This will allow researchers to seek out the existence or non-existence of cortical pockets reserved for certain modalities of sensation, which will be valuable in learning how to later provide appropriate sensory feedback for a prosthesis through cortical stimulation.
ContributorsNaufel, Stephanie (Author) / Helms Tillery, Stephen I (Thesis advisor) / Santos, Veronica J (Thesis advisor) / Buneo, Christopher A (Committee member) / Robert, Jason S (Committee member) / Arizona State University (Publisher)
Created2011
Description
Vagal Nerve Stimulation (VNS) has been shown to be a promising therapeutic technique in treating many neurological diseases, including epilepsy, stroke, traumatic brain injury, and migraine headache. The mechanisms by which VNS acts, however, are not fully understood but may involve changes in cerebral blood flow. The vagus nerve plays a significant role in the regulation of heart rate and cerebral blood flow that are altered during VNS. Here, the effects of acute vagal nerve stimulation using varying stimulation parameters on both heart rate and cerebral blood flow were examined. Laser Speckle Contrast Analysis (LASCA) was used to analyze the cerebral blood flow of male Long–Evans rats. In the first experiment, results showed two distinct patterns of responses to 0.8mA of stimulation whereby animals either experienced a mild or severe decrease in heart rate. Further, animals that displayed mild heart rate decreases showed an increase in cerebral blood flow that persisted beyond VNS. Animals that displayed severe decreases showed a transient decrease in cerebral blood flow followed by an increase that was greater than that observed in mild animals but progressively decreased after VNS. The results suggest two distinct patterns of changes in both heart rate and blood flow that may be related to the intensity of VNS. To investigate the effects of lower levels of stimulation, an additional group of animals were stimulated at 0.4mA. The results showed moderate changes in heart rate but no significant changes in cerebral blood flow in these animals. The results demonstrate that VNS alters both heart rate and cerebral blood flow and that these effects are dependent on current intensity.
ContributorsHillebrand, Peter (M.S.) (Author) / Kleim, Jeffrey A (Thesis advisor) / Helms Tillery, Stephen I (Committee member) / Muthuswamy, Jitendran (Committee member) / Arizona State University (Publisher)
Created2019
Description
Principle-based ethical frameworks, which commonly make use of codes of ethics, have come to be the popular approach in guiding ethical behavior within scientific research. In this thesis project, I investigate the benefits and shortcomings of this approach, ultimately to argue that codes of ethics are valuable as an exercise in developing a reconciled value profile for a given research community, and also function well as an internal and external proclamation of values and norms. However, this approach results in technical adherence, at best, and given the extent to which scientific research now irreversibly shapes our experience as human beings, I argue for the importance of cultivating ethical virtues in scientific research. In the interest of doing so I explore concepts from Aristotelian virtue ethics, to consider how to ameliorate the shortcomings of principle-based approaches. This project was inspired by a call to research and develop an ethical framework upon which to found a cooperative research network that would be aimed at combating the spread of emerging and re-emerging infectious diseases in resource-restricted countries, specifically throughout Latin America. The desire to found this network on an ethics-based framework is to move beyond technical compliance and cultivate a research community committed to integrity, therefore establishing and maintaining trust and communication that will allow for unprecedented productive collaboration and meaningful outcomes. I demonstrate in this thesis that this requires more than a code of ethics, and use this initiative as a case study to exhibit the merit of integrating concepts from virtue ethics.
ContributorsCraer, Jennifer Ryan (Author) / Ellison, Karin (Thesis advisor) / Sarewitz, Daniel (Committee member) / Blattman, Joseph (Committee member) / Robert, Jason S (Committee member) / Arizona State University (Publisher)
Created2017