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I worked on the human-machine interface to improve human physical capability. This work was done in the Human Oriented Robotics and Control Lab (HORC) towards the creation of an advanced, EMG-controlled exoskeleton. The project was new, and any work on the human- machine interface needs the physical interface itself. So I designed and fabricated a human-robot coupling device with a novel safety feature. The validation testing of this coupling proved very successful, and the device was granted a provisional patent as well as published to facilitate its spread to other human-machine interface applications, where it could be of major benefit. I then employed this coupling in experimentation towards understanding impedance, with the end goal being the creation of an EMG-based impedance exoskeleton control system. I modified a previously established robot-to-human perturbation method for use in my novel, three- dimensional (3D) impedance measurement experiment. Upon execution of this experiment, I was able to successfully characterize passive, static human arm stiffness in 3D, and in doing so validated the aforementioned method. This establishes an important foundation for promising future work on understanding impedance and the creation of the proposed control scheme, thereby furthering the field of human-robot interaction.
ContributorsO'Neill, Gerald D. (Author) / Artemiadis, Panagiotis (Thesis director) / Santello, Marco (Committee member) / Santos, Veronica (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2013-05
Description
In 1937 Canadian neurosurgeon Wilder Penfield made the first to attempt to map the sensorimotor cortex of the human brain in his paper entitled Somatic Motor and Sensory Representation in the Cerebral Cortex of Man as Studied by Electrical Stimulation. While analogous experimentation had been carried out previously using animal subjects, Penfield sought to understand the delicate and complex neuronal pathways that served as the hidden control mechanisms for human activity. The motor homunculus that followed from his findings has been widely accepted as the standard model for the relative spatial representation of the functionality of the motor cortex, and has been virtually unaltered since its inception. While Penfield took measures to collect cortical data in a manner as accurately as scientifically possible for the time period, his original model is deserving of further analysis using modern techniques. This study uses functional magnetic resonance imaging (fMRI) to quantitatively determine motor function volumes and spatial relationships for four motor tasks: toe, finger, eyebrow, and tongue. Although Penfield's general representation of the superior-to-inferior spatial distribution of the motor cortex was replicated with reasonable accuracy, relative mean task volumes seem to differ from Penfield's original model. The data was first analyzed in each individual patient's native anatomical space for task comparison within a single subject. The volumes of the motor cortex devoted to the eyebrow and toe tasks, which comprise only small portions of the Penfield homunculus, are shown to be relatively large in their fMRI representation compared to finger and tongue. However, these tasks have large deviation values, indicating a lack of consistency in task volume size among patients. Behaviorally, toe movement may include whole foot movement in some individuals, and eyebrows may include face movement, causing distributions that are more widespread. The data was then analyzed in the Montreal Neurological Institute (MNI) space, which is mathematically normalized for task comparison between different subjects. Tongue and finger tasks were the largest in volume, much like Penfield's model. However, they also had substantial deviation, again indicating task volume size inconsistencies. Since the Penfield model is only a qualitative spatial evaluation of motor function along the precentral gyrus, numerical deviation from the model cannot necessarily be quantified. Hence, the results of this study can be interpreted standalone without a current comparison. While future research will serve to further validate these distances and volumes, this quantitative model of the functionality of the motor cortex will be of great utility for future neurological research and during preoperative evaluations of neurosurgical patients.
ContributorsOland, Gabriel Lee (Author) / Frakes, David (Thesis director) / Santello, Marco (Committee member) / Baxter, Leslie (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2013-05
Description
Understanding more about the similarities and differences in cultural perceptions of climate change-related disease causation can better inform culturally specific public health measures. Using interviews conducted with 685 adults in eight diverse global locations ranging from Fiji and China to England and Phoenix, Arizona, this study explores climate change-disease beliefs within and across diverse cultures and comparisons between cultural and scientific models. A cultural consensus analysis was employed to identify a "culturally correct" model for each study site. Next, a scientific model was generated based on current scientific consensus regarding climate change- disease connections. Using the Quadratic Assignment Procedure (QAP), we determined the amount of correlation shared between the scientific model and each cultural model. The analysis revealed a high level of intercorrelation between the models of English speaking, economically developed sites such as Phoenix, Arizona. Additionally, cultural models from the non-English speaking sites were highly intercorrelated with one another. Overall, the English speaking sites tended to have more complex models with a greater density of causal links. Cultural models from the English speaking sites also demonstrated high levels of correlation with the scientific model. In comparison, the cultural models from the non-English speaking sites exhibited little correlation with the scientific model. Based on these findings, we suggest that cultural beliefs related to climate change-related disease causation may be influenced by complex local factors. For example, differences in education and media influences along with localized differences in climate change impacts may, in part, contribute to divergences between the cultural models.
ContributorsMcAlister, Alyssa Brittney (Author) / Wutich, Amber (Thesis director) / Brewis Slade, Alexandra (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2014-05
Description
A previous study demonstrated that learning to lift an object is context-based and that in the presence of both the memory and visual cues, the acquired sensorimotor memory to manipulate an object in one context interferes with the performance of the same task in presence of visual information about a different context (Fu et al, 2012).
The purpose of this study is to know whether the primary motor cortex (M1) plays a role in the sensorimotor memory. It was hypothesized that temporary disruption of the M1 following the learning to minimize a tilt using a ‘L’ shaped object would negatively affect the retention of sensorimotor memory and thus reduce interference between the memory acquired in one context and the visual cues to perform the same task in a different context.
Significant findings were shown in blocks 1, 2, and 4. In block 3, subjects displayed insignificant amount of learning. However, it cannot be concluded that there is full interference in block 3. Therefore, looked into 3 effects in statistical analysis: the main effects of the blocks, the main effects of the trials, and the effects of the blocks and trials combined. From the block effects, there is a p-value of 0.001, and from the trial effects, the p-value is less than 0.001. Both of these effects indicate that there is learning occurring. However, when looking at the blocks * trials effects, we see a p-value of 0.002 < 0.05 indicating significant interaction between sensorimotor memories. Based on the results that were found, there is a presence of interference in all the blocks but not enough to justify the use of TMS in order to reduce interference because there is a partial reduction of interference from the control experiment. It is evident that the time delay might be the issue between context switches. By reducing the time delay between block 2 and 3 from 10 minutes to 5 minutes, I will hope to see significant learning to occur from the first trial to the second trial.
The purpose of this study is to know whether the primary motor cortex (M1) plays a role in the sensorimotor memory. It was hypothesized that temporary disruption of the M1 following the learning to minimize a tilt using a ‘L’ shaped object would negatively affect the retention of sensorimotor memory and thus reduce interference between the memory acquired in one context and the visual cues to perform the same task in a different context.
Significant findings were shown in blocks 1, 2, and 4. In block 3, subjects displayed insignificant amount of learning. However, it cannot be concluded that there is full interference in block 3. Therefore, looked into 3 effects in statistical analysis: the main effects of the blocks, the main effects of the trials, and the effects of the blocks and trials combined. From the block effects, there is a p-value of 0.001, and from the trial effects, the p-value is less than 0.001. Both of these effects indicate that there is learning occurring. However, when looking at the blocks * trials effects, we see a p-value of 0.002 < 0.05 indicating significant interaction between sensorimotor memories. Based on the results that were found, there is a presence of interference in all the blocks but not enough to justify the use of TMS in order to reduce interference because there is a partial reduction of interference from the control experiment. It is evident that the time delay might be the issue between context switches. By reducing the time delay between block 2 and 3 from 10 minutes to 5 minutes, I will hope to see significant learning to occur from the first trial to the second trial.
ContributorsHasan, Salman Bashir (Author) / Santello, Marco (Thesis director) / Kleim, Jeffrey (Committee member) / Helms Tillery, Stephen (Committee member) / Barrett, The Honors College (Contributor) / W. P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Electromyography (EMG) and Electroencephalography (EEG) are techniques used to detect electrical activity produced by the human body. EMG detects electrical activity in the skeletal muscles, while EEG detects electrical activity from the scalp. The purpose of this study is to capture different types of EMG and EEG signals and to determine if the signals can be distinguished between each other and processed into output signals to trigger events in prosthetics. Results from the study suggest that the PSD estimates can be used to compare signals that have significant differences such as the wrist, scalp, and fingers, but it cannot fully distinguish between signals that are closely related, such as two different fingers. The signals that were identified were able to be translated into the physical output simulated on the Arduino circuit.
ContributorsJanis, William Edward (Author) / LaBelle, Jeffrey (Thesis director) / Santello, Marco (Committee member) / Barrett, The Honors College (Contributor) / Computer Science and Engineering Program (Contributor)
Created2013-12
Description
Obesity has become a major area of research in many fields due to the increasing obesity rate not only in The United States, but also around the world. Research concerning obesity stigma has both physical and mental health implications. Weight bias and obesity stigma represent important research areas for health professionals as they confront these issues on a daily basis in interactions with their patients. To explore how gender, ethnicity, and a person's own BMI affect the stigma of certain weight related terms, a set of 264 participant's surveys on weight related situations on the campus of Arizona State University were analyzed. Using univariate analysis to determine frequency of words deemed most or least acceptable as well as independent t-test for gender and ANOVA for ethnicity and own BMI, we found that participant's view more clinical terms such as "unhealthy BMI" and "BMI" as acceptable words for use during a physician-patient interaction. Analysis across genders revealed the highest number of differences in terms, with females generally ranking terms across the board as less acceptable then men. Differences varied little between ethnicities; however, own BMI revealed more differences between terms; underweight participants did not rank any terms as positive. We analyzed average ATOP (Attitudes Toward Obese People) scores and found that there was no significant difference in average ATOP scores between gender and a participant's own BMI, but a statistical significance did exist between ethnic categories. This study showed that the term "obese/obesity", although normally considered to be a clinical term by many was not ranked as very positive across gender, ethnicity, or own BMI. Based on these findings, new material should be created to inform physicians on how to talk about weight related problems with certain populations of patients.
ContributorsBlasco, Drew Adair (Author) / Wutich, Amber (Thesis director) / Brewis Slade, Alexandra (Committee member) / Barrett, The Honors College (Contributor) / School of Politics and Global Studies (Contributor) / Department of Psychology (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2014-12
Description
Five immunocompetent C57BL/6-cBrd/cBrd/Cr (albino C57BL/6) mice were injected with GL261-luc2 cells, a cell line sharing characteristics of human glioblastoma multiforme (GBM). The mice were imaged using magnetic resonance (MR) at five separate time points to characterize growth and development of the tumor. After 25 days, the final tumor volumes of the mice varied from 12 mm3 to 62 mm3, even though mice were inoculated from the same tumor cell line under carefully controlled conditions. We generated hypotheses to explore large variances in final tumor size and tested them with our simple reaction-diffusion model in both a 3-dimensional (3D) finite difference method and a 2-dimensional (2D) level set method. The parameters obtained from a best-fit procedure, designed to yield simulated tumors as close as possible to the observed ones, vary by an order of magnitude between the three mice analyzed in detail. These differences may reflect morphological and biological variability in tumor growth, as well as errors in the mathematical model, perhaps from an oversimplification of the tumor dynamics or nonidentifiability of parameters. Our results generate parameters that match other experimental in vitro and in vivo measurements. Additionally, we calculate wave speed, which matches with other rat and human measurements.
ContributorsRutter, Erica (Author) / Stepien, Tracy (Author) / Anderies, Barrett (Author) / Plasencia, Jonathan (Author) / Woolf, Eric C. (Author) / Scheck, Adrienne C. (Author) / Turner, Gregory H. (Author) / Liu, Qingwei (Author) / Frakes, David (Author) / Kodibagkar, Vikram (Author) / Kuang, Yang (Author) / Preul, Mark C. (Author) / Kostelich, Eric (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-05-31
Description
Tactile and proprioceptive sensory feedback are the two sensory modalities that make up haptic sensation. The degree which these two sensory modalities are integrated together is not very well known. To investigate this issue a set of experiments were set into motion separating these sensory modalities and testing what happens when a person’s proprioceptive system is perturbed. A virtual reality system with haptic feedback along with a weighted object were utilized in a reach, grasp, and lift task. The subjects would lift two objects sequentially and try to judge which one was heavier. This project was split into three different experiments to measure the subject’s perception in different situations. The first experiment utilized the virtual reality system to measure the perception when the subject only has proprioceptive inputs. The second experiment would include the virtual reality system and the weighted object to act as a comparison to the first experiment with the additional tactile input. The third experiment would then add perturbations to the proprioceptive inputs through the virtual reality system to investigate how perception will change. Results from experiment 1 and 2 showed that subjects are almost just as accurate with weight discrimination even if they only have proprioceptive inputs however, subjects are much more consistent in their weight discrimination with both sensory modalities. Results from experiment 3 showed that subjective perception does change when the proprioception is perturbed but the magnitude of that change in perception depends on the perturbation performed.
ContributorsPerrine, Jacob (Author) / Santello, Marco (Thesis director) / Toma, Simone (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
There is an enormous unmet need for services, education, and outreach to improve women’s breast health. Healthcare systems and insurance systems vary widely around the world, and this may play an important role in understanding variability in women’s breast health knowledge and behavior globally. The goal of this study is to determine how varying healthcare systems in three countries (Japan, Paraguay, US) affect a woman’s likelihood of seeing a physician in regard to their breasts. For example, Japan is a clear example of a region that provides universal health insurance to its citizens. The government takes responsibility in giving accessible and equitable healthcare to its entire population (Zhang & Oyama, 2016). On the other hand, a country such as Paraguay is composed of both public and private sectors. In order for citizens to gain insurance, one would have to either be formally employed or choose to pay out-of-pocket for hospital visits (“Paraguay”, 2017). A country such as the United States does not have universal health insurance. However, it does have a mix of public and private sectors, meaning there is little to no coverage for its citizens. To accommodate for this, the United States came up with the Affordable Care Act, which extends coverage to the uninsured. Although the United States might be a country that spends more on healthcare than any other nation, there are residents that still lack healthcare (De Lew, Greenberg & Kinchen, 1992). This study, then, compares women’s breast health knowledge and behavior in Japan, Paraguay, and the US. Other variables, which are also considered in this study, that might affect this include wealth level, education, having general awareness of breast cancer, having regular health checks, and having some breast education. Using statistical analysis of breast check rates of women in Japan, Paraguay, and the United States, this research found that women sampled in Asunción, Paraguay check their breasts more often than either women sampled from Scottsdale, U.S. or Osaka, Japan. It was also found that women sampled from Paraguay were more confident in detecting changes in their breast compared to women sampled from the Japan or the US. Finally, it was noted that women sampled from Japan were least likely to partake in seeing a doctor in concern of changes in their breasts compared to women sampled from the other two research locations. These findings have relevance for the implementation of advocacy and public education about breast health.
ContributorsKumar, Navneet Surjit (Co-author) / Kumar, Navneet (Co-author) / Wutich, Amber (Thesis director) / Brewis, Alexandra (Committee member) / School of Human Evolution & Social Change (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Abstract
According to the National Institute on Deafness and other Communication Disorders (NIDCD), approximately 37 million Americans suffer from some degree of hearing loss, which impacts their ability to communicate fluently with the hearing world. This number includes up to 17% of the adult population, many who have experienced post-lingual or late-deafness. While hearing loss is known to be one of the most prevalent chronically disabling sensory conditions, little is known about the impact it has on individuals’ cultural identity and sense of well-being. There is somewhat of a deficit in the research literature addressing these issues of cultural identity, especially as it relates to post-lingually deaf adults. Improved knowledge of these dimensions of hearing loss is needed—a knowledge which could lead to more effective resources for late-deafened people. Though hearing loss can be disabling, access to American Sign Language and the Deaf culture may compensate for social and cultural loss and potentially improve well-being within late-deafened individuals. Using the framework of Social Identity Theory and Neil Glickman’s Deaf Identity Development model, this study sought to identify late-deafened adults who fall into the marginal category, placing them at greater risk of becoming socially marginalized and experiencing diminished well-being. Subjective well-being was then measured by the Flourishing Scale to determine how being socially marginal may impact one’s sense of self, personal prosperity, social efficacy, and sense of social competency. Results showed that marginal individuals do experience diminished subjective well-being, a fact which should be further explored by researchers, especially in the context of developing more effective interventions and services for late-deafened individuals.
According to the National Institute on Deafness and other Communication Disorders (NIDCD), approximately 37 million Americans suffer from some degree of hearing loss, which impacts their ability to communicate fluently with the hearing world. This number includes up to 17% of the adult population, many who have experienced post-lingual or late-deafness. While hearing loss is known to be one of the most prevalent chronically disabling sensory conditions, little is known about the impact it has on individuals’ cultural identity and sense of well-being. There is somewhat of a deficit in the research literature addressing these issues of cultural identity, especially as it relates to post-lingually deaf adults. Improved knowledge of these dimensions of hearing loss is needed—a knowledge which could lead to more effective resources for late-deafened people. Though hearing loss can be disabling, access to American Sign Language and the Deaf culture may compensate for social and cultural loss and potentially improve well-being within late-deafened individuals. Using the framework of Social Identity Theory and Neil Glickman’s Deaf Identity Development model, this study sought to identify late-deafened adults who fall into the marginal category, placing them at greater risk of becoming socially marginalized and experiencing diminished well-being. Subjective well-being was then measured by the Flourishing Scale to determine how being socially marginal may impact one’s sense of self, personal prosperity, social efficacy, and sense of social competency. Results showed that marginal individuals do experience diminished subjective well-being, a fact which should be further explored by researchers, especially in the context of developing more effective interventions and services for late-deafened individuals.
ContributorsBlech, Jennifer Grace (Author) / Almasan, Oana (Thesis director) / Wutich, Amber (Committee member) / School of Human Evolution & Social Change (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2019-12