Matching Items (13)

Filtering by

Clear all filters

131377-Thumbnail Image.png

Using Graphene as a Flex Resistor to Detect Biodynamics

Description

Over the past 30 years the use of graphene has been increasing at a rapid rate. The reason why graphene has become more popular is because it is starting to be understood better, and researchers are starting to recognize graphene’s

Over the past 30 years the use of graphene has been increasing at a rapid rate. The reason why graphene has become more popular is because it is starting to be understood better, and researchers are starting to recognize graphene’s unique properties. Graphene is a single atomic layer of graphite, and graphite is a three-dimensional cube base structure of carbon. Graphite has a high conductivity rate, and graphene has an even higher conductivity, meaning that graphene makes for an excellent resistor in any hardware system. Graphene is flexible, has high durability, and can vary in resistance based on its shape (Sharon 2015). With graphene being able to change its resistivity, it can act as different types of sensors. These sensors include measuring pressure, resistance, force, strain, and angle. One problem across the globe is that patients have arthritis, decaying bone density, and injuries which can easily go mistreated or not treated at all. It can be hard to determine the severity of injuries in joints by observation of the patient. There are tools and equipment that will allow a doctor to track the force and degrees of motion of certain joints, but they are mostly limited to hospitals. With graphene acting as a sensor it can be embedded into casts, braces, and even clothing. With a mobile sensor that relays accurate and continuous data to a doctor they can more precisely determine a therapy or recovery time that will better suit the patients’ needs. In this project the graphene was used to measure the angle of a patient’s wrist while they were wearing a wrist brace. From the data collected, the graphene was able to track the user’s movement of their wrist as they moved it in a single direction. The data showed the angle of the wrist ranging from zero degrees to 90 degrees. This proves that graphene can shape the way biosensing is accomplished. Biodynamics is a growing field, and with more injuries everyday it is important to study graphene and how it can be used to diagnose and prevent injuries related to joints. Graphene can be used as a biosensor which can then be implemented into a brace to allow for accurate biodynamic tracking.

Contributors

Agent

Created

Date Created
2020-05

132475-Thumbnail Image.png

[Detection of Heel-off Initiation Based on the Relationship Between Ground Reaction Forces and Surface Electromyography: Heel-toe, Heel-toe, a Story]

Description

The global population over the age of 60 is estimated to rise to 23% by 2050 only increase the prevalence of functional neurological disorders and stroke. Increase in cases of functional neurological disorders and strokes will place a greater burden

The global population over the age of 60 is estimated to rise to 23% by 2050 only increase the prevalence of functional neurological disorders and stroke. Increase in cases of functional neurological disorders and strokes will place a greater burden on the healthcare industry, specifically physical therapy. Physical therapy is vital for a patient’s recovery of motor function which is time demanding and taxing on the physical therapist. Wearable robotics have been proven to improve functional outcomes in gait rehabilitation by providing controlled high dosage and high-intensity training. Accurate control strategies for assistive robotic exoskeletons are vital for repetitive high precisions assistance for cerebral plasticity to occur.

This thesis presents a preliminary determination and design of a control algorithm for an assistive ankle device developed by the ASU RISE Laboratory. The assistive ankle device functions by compressing a spring upon heel strike during gait, remaining compressed during mid-stance and then releasing upon initiation of heel-off. The relationship between surface electromyography and ground reactions forces were used for identification of user-initiated heel-off. The muscle activation of the tibialis anterior combined with the ground reaction forces of the heel pressure sensor generated potential features that will be utilized in the revised control algorithm for the assistive ankle device. Work on this project must proceed in order to test and validate the revised control algorithm to determine its accuracy and precision.

Contributors

Agent

Created

Date Created
2019-05

132702-Thumbnail Image.png

Delays in reticulospinal system are correlated with deficits in motor learning in older adults.

Description

Motor skill acquisition, the process by which individuals practice and consolidate movement to become faster, more accurate and efficient, declines with age. Initial skill acquisition is dominated by cortical structures; however as learning proceeds, literature from rodents and songbirds suggests

Motor skill acquisition, the process by which individuals practice and consolidate movement to become faster, more accurate and efficient, declines with age. Initial skill acquisition is dominated by cortical structures; however as learning proceeds, literature from rodents and songbirds suggests that there is a transition away from cortical execution. Recent evidence indicates that the reticulospinal system plays an important role in integration and retention of learned motor skills. The brainstem has known age-rated deficits including cell shrinkage & death. Given the role of the reticulospinal system in skill acquisition and older adult’s poor capacity to learn, it begs the question: are delays in the reticulospinal system associated with older adult’s poor capacity to learn?
Our objective was to evaluate if delays in the reticulospinal system (measured via the startle reflex) are correlated to impairment of motor learning in older adults. We found that individuals with fast startle responses resembling those of younger adults show the most learning and retention of that learning while individuals with delayed startle responses show the least. Moreover, linear regression analysis indicated that startle onset latency exists within a continuum of learning outcomes suggesting that startle onset latency may be a sensitive measure to predict learning deficits in older adults. As there exists no method to determine an individual’s relative learning capacity, these results open the possibility of startle, which is an easy and inexpensive behavioral measure, being used to predict learning deficits in older adults to facilitate better dosing during rehabilitation therapy.

Contributors

Agent

Created

Date Created
2019-05

131923-Thumbnail Image.png

Investigating the Effect of Sleep Deprivation on the Startle Response

Description

Older adults tend to learn at a lesser extent and slower rate than younger individuals. This is especially problematic for older adults at risk to injury or neurological disease who require therapy to learn and relearn motor skills. There is

Older adults tend to learn at a lesser extent and slower rate than younger individuals. This is especially problematic for older adults at risk to injury or neurological disease who require therapy to learn and relearn motor skills. There is evidence that the reticulospinal system is critical to motor learning and that deficits in the reticulospinal system may be responsible, at least in part, for learning deficits in older adults. Specifically, delays in the reticulospinal system (measured via the startle reflex) are related to poor motor learning and retention in older adults. However, the mechanism underlying these delays in the reticulospinal system is currently unknown.

Along with aging, sleep deprivation is correlated with learning deficits. Research has shown that a lack of sleep negatively impacts motor skill learning and consolidation. Since there is a link between sleep and learning, as well as learning and the reticulospinal system, these observations raise the question: does sleep deprivation underlie reticulospinal delays? We hypothesized that sleep deprivation was correlated to a slower startle response, indicating a delayed reticulospinal system. Our objectives were to observe the impact of sleep deprivation on 1) the startle response (characterized by muscle onset latency and percentage of startle responses elicited) and 2) functional performance (to determine whether subjects were sufficiently sleep deprived).

21 young adults participated in two experimental sessions: one control session (8-10 hour time in bed opportunity for at least 3 nights prior) and one sleep deprivation session (0 hour time in bed opportunity for one night prior). The same protocol was conducted during each session. First, subjects were randomly exposed to 15 loud, startling acoustic stimuli of 120 dB. Electromyography (EMG) data measured muscle activity from the left and right sternocleidomastoid (LSCM and RSCM), biceps brachii, and triceps brachii. To assess functional performance, cognitive, balance, and motor tests were also administered. The EMG data were analyzed in MATLAB. A generalized linear mixed model was performed on LSCM and RSCM onset latencies. Paired t-tests were performed on the percentage of startle responses elicited and functional performance metrics. A p-value of less than 0.05 indicated significance.

Thirteen out of 21 participants displayed at least one startle response during their control and sleep deprived sessions and were further analyzed. No differences were found in onset latency (RSCM: control = 75.87 ± 21.94ms, sleep deprived = 82.06 ± 27.47ms; LSCM: control = 79.53 ± 17.85ms, sleep deprived = 78.48 ± 20.75ms) and percentage of startle responses elicited (control = 84.10 ± 15.53%; sleep deprived = 83.59 ± 18.58%) between the two sessions. However, significant differences were observed in reaction time, TUG with Dual time, and average balance time with the right leg up. Our data did not support our hypothesis; no significant differences were seen between subjects’ startle responses during the control and sleep deprived sessions. However, sleep deprivation was indicated with declines were observed in functional performance. Therefore, we concluded that sleep deprivation may not affect the startle response and underlie delays in the reticulospinal system.

Contributors

Created

Date Created
2020-05

131928-Thumbnail Image.png

The Impact of a Starting Acoustic Stimulus and Transcranial Magnetic Stimulation on Reaction Times in Unimpaired Adults

Description

Motor skill acquisition, the process by which individuals practice and consolidate
movement to become faster, more accurate and efficient, declines with age. Initial skill acquisition is dominated by cortical structures; however as learning proceeds, literature from
rodents and songbirds suggests

Motor skill acquisition, the process by which individuals practice and consolidate
movement to become faster, more accurate and efficient, declines with age. Initial skill acquisition is dominated by cortical structures; however as learning proceeds, literature from
rodents and songbirds suggests that there is a transition away from cortical execution. Recent
evidence indicates that the reticulospinal system plays an important role in integration and
retention of learned motor skills. The brainstem has known age-rated deficits including cell
shrinkage & death. Given the role of the reticulospinal system in skill acquisition and older
adult’s poor capacity to learn, it begs the question: are delays in the reticulospinal system
associated with older adult’s poor capacity to learn?
Our objective was to evaluate if delays in the reticulospinal system (measured via the
startle reflex) and corticospinal system (measured via Transcranial Magnetic Stimulation (TMS) are correlated to impairment of motor learning in older adults. We found that individuals with fast startle responses resembling those of younger adults show the most improvement and retention while individuals with delayed startle responses show the least. We also found that there was no relationship between MEP latencies and improvement and retention. Moreover, linear regression analysis indicated that startle onset latency exists within a continuum of learning outcomes suggesting that startle onset latency may be a sensitive measure to predict learning deficits in older adults. As there exists no method to determine an individual’s relative learning capacity, these results open the possibility of startle, which is an easy and inexpensive behavioral measure and can be used to determine learning deficits in older adults to facilitate better dosing during rehabilitation therapy.

Contributors

Agent

Created

Date Created
2020-05

137074-Thumbnail Image.png

A Simpler Method To Evaluate The Knee Adduction Moment During Gait Using Plantar Pressure Measurements

Description

Medial compartment knee osteoarthritis (OA) is a disease whose severity has been associated with the peak adduction moment during walking (pKAM). Unfortunately, measuring patients' pKAM to track their therapy progress involves the use of a gait laboratory which is expensive

Medial compartment knee osteoarthritis (OA) is a disease whose severity has been associated with the peak adduction moment during walking (pKAM). Unfortunately, measuring patients' pKAM to track their therapy progress involves the use of a gait laboratory which is expensive and time intensive. This study aimed to develop and assess a regression method to predict the pKAM using only plantar pressure measurements. This approach could greatly reduce the burden of evaluating pKAM.

Contributors

Agent

Created

Date Created
2014-05

137004-Thumbnail Image.png

Optimizing Biofeedback and Learning in an EEG-Based Brain-Computer Interface

Description

Brain-computer interface technology establishes communication between the brain and a computer, allowing users to control devices, machines, or virtual objects using their thoughts. This study investigates optimal conditions to facilitate learning to operate this interface. It compares two biofeedback methods,

Brain-computer interface technology establishes communication between the brain and a computer, allowing users to control devices, machines, or virtual objects using their thoughts. This study investigates optimal conditions to facilitate learning to operate this interface. It compares two biofeedback methods, which dictate the relationship between brain activity and the movement of a virtual ball in a target-hitting task. Preliminary results indicate that a method in which the position of the virtual object directly relates to the amplitude of brain signals is most conducive to success. In addition, this research explores learning in the context of neural signals during training with a BCI task. Specifically, it investigates whether subjects can adapt to parameters of the interface without guidance. This experiment prompts subjects to modulate brain signals spectrally, spatially, and temporally, as well differentially to discriminate between two different targets. However, subjects are not given knowledge regarding these desired changes, nor are they given instruction on how to move the virtual ball. Preliminary analysis of signal trends suggests that some successful participants are able to adapt brain wave activity in certain pre-specified locations and frequency bands over time in order to achieve control. Future studies will further explore these phenomena, and future BCI projects will be advised by these methods, which will give insight into the creation of more intuitive and reliable BCI technology.

Contributors

Agent

Created

Date Created
2014-05

135593-Thumbnail Image.png

Learning Dynamic Manipulation with Redundant Degrees of Freedom: Sub-Optimal Motor Solution induced by switching tasks

Description

The effect of conflicting sensorimotor memories on optimal force strategies was explored. Subjects operated a virtual object controlled by a physical handle to complete a simple straight-line task. Perturbations applied to the handle induced a period of increased error in

The effect of conflicting sensorimotor memories on optimal force strategies was explored. Subjects operated a virtual object controlled by a physical handle to complete a simple straight-line task. Perturbations applied to the handle induced a period of increased error in subject accuracy. After two blocks of 33 trials, perturbations switched direction, inducing increased error from the previous trials. Subjects returned after a 24-hour period to complete a similar protocol, but beginning with the second context and ending with the first. Interference from the first context on each day caused an increase in initial error for the second (P < 0.05). Following the rest period, subjects showed retention of the sensorimotor memory from the previous day through significantly decreased initial error (P = 3x10-6). However, subjects showed an increase in forces for each new context resulting from a sub-optimal motor strategy. Higher levels of total effort (P < 0.05) and a lack of separation between force values for opposing and non-opposing digits (P > 0.05) indicated a strategy that used more energy to complete the task, even when rates of learning appeared identical or improved. Two possible mechanisms for this lack of energy conservation have been proposed.

Contributors

Agent

Created

Date Created
2016-05

137762-Thumbnail Image.png

Game Based Approaches to Learning: A Case Study of The Doctor's Cure and Teaching Styles

Description

This paper explores the use of different classroom management styles by teachers engaged in a study. The study was focused on testing an educational computer program called The Doctor's Cure in s southwester school district with ready access to computers.

This paper explores the use of different classroom management styles by teachers engaged in a study. The study was focused on testing an educational computer program called The Doctor's Cure in s southwester school district with ready access to computers. The Doctor's Cure uses interactive storytelling and transformational play to teach seventh graders how to write persuasively. The definitions of student centered and teacher centered management styles used in this paper are drawn from Garret (2008) which suggests that teachers are not entirely one management style or the other, but a mix of the two. This paper closely examines three teachers, two with teacher centered styles and one with a student centered style in order to see which style was most effective in promoting the learning of persuasive writing skills. The findings tentatively indicate that teacher centered management styles yield larger gains in learning compared to more student centered styles.

Contributors

Agent

Created

Date Created
2013-05

132176-Thumbnail Image.png

Development of an OpenSim Simulation to Identify Time and Force Magnitude Needed at Toe-Off Stage for an Assistive Force Ankle Device

Description

Human walking is a complex and rhythmical activity that comprises of the brain, nerves and muscles. Neuromuscular disorder (NMD) is a broad term that refers to conditions that affect the proper use of muscles and nervous system, thus also impairing

Human walking is a complex and rhythmical activity that comprises of the brain, nerves and muscles. Neuromuscular disorder (NMD) is a broad term that refers to conditions that affect the proper use of muscles and nervous system, thus also impairing the walking or gait cycle of an individual. The improper gait cycle might be attributed to the lack of force produced at the toe-off stage. This project addresses if it is possible to create an OpenSim model to find the ideal time and force magnitude needed of an assistive force ankle device to improve gait patterns in individuals with NMD.

Contributors

Agent

Created

Date Created
2019-05