Motor Control Commons^™

Nonlinear Differences In Postural Sway Across Attentional Focus Conditions In Individuals With And Without Anterior Cruciate Ligament Reconstruction, Natalie L. Ferguson, Brian L. Cone, Christopher K. Rhea, Anne Beethe, Breanna Studenka

Rehabilitation Sciences Faculty Publications

BACKGROUND: The structure of variability in postural sway reflects the adaptability and health of the postural control system. Entropy quantifies this structure by measuring the regularity of repeated fluctuations over time. Although entropy has been used to examine sway in neurological populations, little is known about how sway complexity changes following anterior cruciate ligament reconstruction (ACLR). Attentional focus may also influence postural control, with external focus typically promoting more efficient and automatic regulation than internal focus.

AIM: To examine how attentional focus (internal vs. external) influences the structure of postural sway in individuals with and without ACLR.

METHODS: Forty-three participants …

Neural Efficiency Hypothesis In Motor Actions; Spectral Power Of Balancing Ballet Dancers, Carter G. Disantis

Senior Theses

Reduced activity observed during functional imaging of motor experts led to the Neural Efficiency Hypothesis (NEH) in motor skills, which posits that expert performers use fewer neural resources during motor execution than novices, reflecting greater neural efficiency.

This pilot study compared EEG recordings from five novices and four expert ballet dancers during standing and one-leg balance. Whole-brain theta (4–8 Hz) and alpha (8–12 Hz) power were quantified, and topographic maps were generated. In addition to testing the primary hypotheses, the experimental design was evaluated as a practical and scalable approach for investigating the NEH in motor skills. Novices showed significantly …

Computational Approaches For Diagnosing Neurological Impairments And Restoring Functional Movement, Serhii Bahdasariants

Graduate Theses, Dissertations, and Problem Reports (ETD)

Movement is the primary means by which the nervous system converts intention into interaction with the environment. Voluntary limb motion enables standing, walking, reaching, and grasping—actions that underpin self‑care, communication, and economic participation. When diseases or injuries disrupt the pathways that couple neural commands to muscle forces—whether through cortical stroke, spinal cord injury, or peripheral nerve damage—mechanical outcomes such as weakness, loss of coordination, and ultimately reduced mobility emerge. These impairments cascade into secondary complications, increased dependence on caregivers, and diminished quality of life. Quantifying how the lesion alters the mechanics of movement is therefore essential for designing targeted interventions …

Modulation Of Persistent Inward Currents With Changes In Posture And Cutaneous Sensory Input, Ryan William Weller

Theses and Dissertations (Comprehensive)

Spinal motor neuron (MN) persistent inward currents (PIC) increase and sustain the MN output. PIC is amplified by descending monoamines and reduced by afferent inhibition. There is strong coupling between plantar cutaneous sensory input and lower limb MNs. Given that monoaminergic drive is altered with postures and motor tasks, our purpose was to assess posture-dependent plantar cutaneous sensory modulation of tibialis anterior (TA) MNs. We hypothesize that: 1) a supine position will suppress PIC, 2) removing the load from the bottom of the heel will inflate PIC, and 3) cutaneous stimulation of the plantar aspect of the heel will reduce …

Compensating For Effects Of Autotomy On Locomotion In Stink Bugs (Halyomorpha Halys), Lilian C. Jubb

Longwood Senior Thesis Proposal

Autotomy is the voluntary release of an appendage, typically to avoid predation or entrapment. Autonomy of a single leg can have minimal effects on locomotion in arthropods with more than six legs. Hexapods, however, use a double-tripod gait which is completely disrupted with the loss of a single leg, thus locomotor performance should be greatly reduced leading to lower survival. Autotomy is so costly to locomotion that some insects regenerate a lost limb in a subsequent molt leading to reduced investment in other important functions (e.g. reproduction). Autotomy persists in adult hexapods with no opportunity for regeneration, which suggests some …

Effects Of Creative Movement & Play Based Interventions On Motor Skills Of Children With Autism Spectrum Disorder: Results From A Randomized Controlled Trial, Sharanya Chandu

Honors Scholar Theses

Objective: The purpose of this study was to assess the effects of creative movement, general movement, and seated play interventions on bilateral coordination, balance, and upper limb coordination motor skills of children with autism spectrum disorder.

Methods: This data was collected as a part of a multisite intervention study, Play and Move study, by the University of Connecticut and University of Delaware. Participants were contacted through the SPARK database, UConn Kids, fliers sent to local autism services, schools, community centers and by posting information online or to listservs. Forty-five children agreed to participate in this study and were randomly assigned …

Gaze During Turning In Older Adults, Kalina Mavrov

Theses/Capstones/Creative Projects

To navigate complex environments, our gaze needs to attenuate to locomotor tasks, such as walking and turning. Shifting gaze (i.e., rotation of the eyes and head), is important when moving through different environments. The aim of this study was to compare gaze anticipation during clinical tests and complex real-world locomotion. I hypothesized that older adults would shift their gaze in a new heading direction in anticipation of turns. I further predicted increased gaze anticipation in tasks that have a high demand for spatial orientation. Participants were asked to complete clinical tasks consisting of a 2-minute walk, figure-8, and 360-turning in …

Linking Spinal Cord Circuits With Upper Limb Sensorimotor Control In Adults With Cerebral Palsy, Saihari Dukkipati

Theses & Dissertations

Cerebral palsy (CP) is the most common neurological disorder originating in childhood, but most of the people living with CP are currently adults. While people with CP continue to get older, the amount of research focused on adults has been rather limited. The early childhood insults leading to CP are thought to originate in the brain, but the effects on the entire neuromuscular system across the lifespan have only recently started to be explored. Of note, recent neuroimaging evidence suggests that the cervical spinal cord structure is atypical in adults with CP. However, it is largely unclear how the neurophysiological …

Beginnings, Elizabeth Becker

Dance (MFA) Theses

Researcher Elizabeth Becker uses personal experiences of pregnancy alongside scholarly research on the developmental movement patterns of the human embryo, fetus, and newborn’s first year of life to explore the multiplicity of these movement patterns within and outside the womb. Becker explores the relationship between the fertilization, germinal, embryonic, and fetal stages in relation to a newborn and its mother. These movement patterns within the beginning stages of life are valuable to research because they simulate neurodevelopmental patterns, which help wire the central nervous system in early childhood. These movements also help lay the foundation for sensory-motor development and life-long …

Neuromuscular Control Strategy During Object Transport While Walking: Adaptive Integration Of Upper And Lower Limb Movements, Ahyoung Song

LSU Doctoral Dissertations

When carrying an object while walking, a significant challenge for the central nervous system (CNS) is to preserve the object’s stability against the inter-segmental interaction torques and ground reaction forces. Studies documented several strategies used by the CNS: modulation of grip force (GF), alterations in upper limb kinematics, and gait adaptations. However, the question of how the CNS organizes the multi-segmental joint and muscle coordination patterns to deal with gait-induced perturbations remains poorly understood. This dissertation aimed to explore the neuromuscular control strategy utilized by the CNS to transport an object during walking successfully. Study 1 examined the inter-limb coordination …

Geometric Visual Illusion Effects On Visual Perception And Visuomotor Control: Emphasis On The Vertical-Horizontal Illusion, Shijun Yan

LSU Doctoral Dissertations

The focus of this dissertation was to explore the effects of potential vertical-horizontal (V-H) illusory influences on perceptuomotor control. As part of this focus, we examined the potential use of separate cortical visual streams: the ventral visual stream for perception and the dorsal visual stream for action. Three studies were conducted to determine the effects of the V-H illusion influences on length estimations using upper limb point-to-point movements and lower limb stepping movements, involving various illusory configurations, movement directions, gaze directions. After a short introduction (Chapter 1) and a more detailed review of existing literature (Chapter 2), we present manuscripts …

An Investigation Of The Effect Of Chewing On Rhythmic Motor Tasks, Brittany S. Samulski

Rehabilitation Sciences Theses & Dissertations

Chewing gum and walking has traditionally been cited as the quintessentially difficult dual task, but little is known regarding chewing effects on motor control. The aims of this dissertation include describing chewing patterns across adulthood, describing chewing’s influence on secondary motor tasks, and investigate entrainment patterns of chewing and gait per established patterns of coupled oscillators. Three experiments were conducted to describe chewing patterns and to examine the effect chewing has on other motor tasks, particularly walking, in young and old adults. The first experiment used a metronome to manipulate chewing rates and measured associated gait parameters. This experiment established …

Biomechanics And Neural Control Of Movement: Cmi's Effects On Downstream Motor Processing And Gait In Forwards And Backwards Walking, Christopher Choi

CMC Senior Theses

Analyzing the effects of cognitive motor interferences (CMI) on walking is usually done in patients with neurological comorbidity or during forward walking (FW). However, there are few studies that examine gait differences between FW and backward walking (BW) under the presence of CMI when speed is kept constant on a treadmill. In this study we examined how CMI would disrupt sensory feedback and affect the descending motor pathway. We hypothesized that subjects that walked backwards and were given a cognitive task would show the greatest differences in gait due to a lack of visual input and the presence of CMI. …

Neuromechanical Tuning For Arm Motor Control, Russell Lee Hardesty Jr

Graduate Theses, Dissertations, and Problem Reports (ETD)

Movement is a fundamental behavior that allows us to interact with the external world. Its importance to human health is most evident when it becomes impaired due to disease or injury. Physical and occupational rehabilitation remains the most common treatment for these types of disorders. Although therapeutic interventions may improve motor function, residual deficits are common for many pathologies, such as stroke. The development of novel therapeutics is dependent upon a better understanding of the underlying mechanisms that govern movement. Movement of the human body adheres to the principles of classic Newtonian mechanics. However, due to the inherent complexity of …

Spinal Motor Neuron Excitability And Balance Control Changes Following Downslope Walking, Nikki Aitcheson-Huehn

Theses and Dissertations (Comprehensive)

Downslope walking (DSW) has been proposed as a rehabilitation tool for people with Multiple Sclerosis (PwMS) although there are mixed findings in young adults (YA) regarding the balance control changes, despite both populations experiencing depressed spinal motor neuron (MN) pool excitability. Our aim was to determine whether YAs could demonstrate improved balance control in conjunction with SOL H reflex depression (estimate of spinal MN excitability) following DSW. We also aimed to determine whether reciprocal inhibition was a potential mechanism for H reflex depression via conditioned SOL H reflexes. Thirty young adults (23±1.4y, 6 males) were assigned to 30-minutes of DSW …

The Neurophysiological Changes Associated With Motor Learning In Adults And Adolescents, James E. Gehringer

Theses & Dissertations

One main purpose of this dissertation was to explore how sensorimotor cortical oscillations changed after practicing a novel ankle plantarflexion target matching task. We behaviorally quantified the speed, accuracy, reaction time, velocity, and variability of the participant’s performance of the task, while collecting their neurophysiological responses with magnetoencephalography (MEG). With these data, we assessed how the motor planning and execution stages of movement during a goal directed target matching task changed after practicing a task in typically developing young adults with their non-dominant ankle. We found that the cortical oscillations in the beta frequency range that were sourced from the …

Validity And Reliability Of A 5-Minute Web-Camera Based Eye Tracking Test To Assess Visual Memory And Cognition, Emily Bates

Graduate Theses and Dissertations

There are approximately 5.7 million Americans currently living with Alzheimer’s Disease (AD). Early detection of cognitive impairment allows for earlier treatment, potentially slowing or halting cognitive decline. A 30-min web-camera eye tracking assessment (30-min VPC) has been validated as a tool to predict AD risk. However, a shorter version would allow for greater scalability and improve user experience. The purpose of this study was to: 1) determine the validity of the 5-minute web-camera based VPC test with the 30-min test, 2) determine the test-retest reliability of the 5-min test, 3) compare the 5-minute test scores of cognitively intact adults (18-39 …

Longitudinal Tracking Of Physiological State With Electromyographic Signals., Robert Warren Stallard

Electronic Theses and Dissertations

Electrophysiological measurements have been used in recent history to classify instantaneous physiological configurations, e.g., hand gestures. This work investigates the feasibility of working with changes in physiological configurations over time (i.e., longitudinally) using a variety of algorithms from the machine learning domain. We demonstrate a high degree of classification accuracy for a binary classification problem derived from electromyography measurements before and after a 35-day bedrest. The problem difficulty is increased with a more dynamic experiment testing for changes in astronaut sensorimotor performance by taking electromyography and force plate measurements before, during, and after a jump from a small platform. A …

Examining The Relationship Between State Anxiety And Vestibular And Ocular Motor Impairments And Symptoms In High School Athletes With Concussion, Mallory Kathleen Mcelroy

Graduate Theses and Dissertations

Anxiety has been associated with vestibular and ocular motor impairment in the general population. However, there is limited research regarding the connection between the vestibular and ocular motor systems and anxiety following sport-related concussion (SRC). OBJECTIVE: The purpose of this study is to compare state anxiety between concussed adolescent male and female athletes with and without vestibular and ocular motor impairments and symptoms. DESIGN: Prospective, repeated measures SUBJECTS: Thirty adolescent athletes between the ages of 15-18 years, diagnosed with a SRC completed the STAI-State at initial and medical clearance clinical visit. These adolescent athletes were categorized into vestibular and ocular …

Exercise, Cognition, And The Aging Process Among Active, Competitive, And Sedentary Middle-Aged And Older Adults, Katherine Adams

Health, Human Performance and Recreation Undergraduate Honors Theses

Purpose This study aimed to compare the cognitive measures of reaction time and dual-task performance among recreationally active, master athletes, and sedentary older adults aged 50 years or older. Methods 59 late middle-aged and older adults between the ages of 50 to 88 years old participated in reaction time and dual-task tests of which consisted of multiple trials on the same day. Subjects were placed either into the recreationally active, masters athlete, or sedentary activity level group based on the Rapid Assessment of Physical Activity (RAPA) form. For the gait speed with associated dual-task component, subjects walked 10-meters at two …

P30. Optimizing Current Steering In Deep Brain Stimulation For Treating Parkinsonian Axial Motor Symptoms, Daphne Hui

Western Research Forum

Background: The proposed study will investigate deep brain stimulation (DBS), of the subthalamic nucleus (STN) to improve gait dysfunctions in advanced Parkinson’s Disease (PD). DBS requires implantation of electrodes into the brain that contain contacts where current traverses to stimulate neurons. Imprecise electrode implantations are inherent in surgical implantation; thus, contributing to the elusiveness of DBS on gait.

Methods: The proposed investigation will divide current between two contacts to receive 0, 30, 50, 70, or 100% of current, to find the best combination to improve gait. Gait changes associated with fractional combinations will be visually assessed with clinical scales, and …

Motor Control In Individuals With Multiple Sclerosis, David Arpin

Theses & Dissertations

This dissertation explored motor control in individuals with multiple sclerosis (MS) by quantifying the behavioral and neurophysiological deficits present in these individuals. We behaviorally quantified the precision of the ankle plantarflexor musculature of individuals with MS. Our results indicated that the individuals with MS had a greater amount of variability in the precision of the isometric ankle torques, and that this greater variability was related to decreased walking performance. To further explore whether these motor control deficits were due to aberrant cortical activity associated with planning motor actions, we used magnetoencephalography to assess the motor planning and execution stages of …

Hpcnmf: A High-Performance Toolbox For Non-Negative Matrix Factorization, Karthik Devarajan, Guoli Wang

COBRA Preprint Series

Non-negative matrix factorization (NMF) is a widely used machine learning algorithm for dimension reduction of large-scale data. It has found successful applications in a variety of fields such as computational biology, neuroscience, natural language processing, information retrieval, image processing and speech recognition. In bioinformatics, for example, it has been used to extract patterns and profiles from genomic and text-mining data as well as in protein sequence and structure analysis. While the scientific performance of NMF is very promising in dealing with high dimensional data sets and complex data structures, its computational cost is high and sometimes could be critical for …

The Effects Of External Focus Of Attention Exercise Rehabilitation On Dual Task Walking In Parkinson's Disease, Eric N. Beck

Theses and Dissertations (Comprehensive)

Parkinson’s disease impairs control of well-learned movements, and therefore, individuals with Parkinson’s disease are forced to walk with greater conscious control. This causes difficulties while walking and completing a secondary task simultaneously (dual tasking), in that distractions from conscious control of walking increase the risk of falls and injury. Although, attention-based exercise may be a potential avenue to decrease the demands associated with walking in Parkinson’s disease. For example, an external focus of attention (on manipulated objects) has been found to recruit the networks that are important for walking with little conscious control (automatic control networks). In contrast, an internal …

Influence Of Planning Resources On Gait Control In Parkinson’S Disease, Frederico P. Faria

Theses and Dissertations (Comprehensive)

Movement disturbances in individuals with Parkinson’s disease (PD) have been associated with difficulties to plan complex actions. Performance of simple and complex actions overloads resources for individuals with Parkinson’s disease (PD). However, it is unclear if central resources required to plan gait adjustments while walking exacerbate gait disturbances of patients with PD. More specifically, it is unclear how gait impairments, sensory processing, and the dopaminergic system influence the load on processing resources (e.g. cognitive load) during the planning of step modifications. In order to investigate the relative influence of these factors on cognitive load and its impact on gait control, …

Development Of A System For Analysis Of Muscle Contraction Pattern During Drosophila Melanogaster Crawling Behavior, Mary Catherine Decker

Celebrating Scholarship & Creativity Day (2011-2017)

The aim of this study was to attain footage of the crawling Drosophila larva from 360° angles in order to visualize the pattern of individual muscle contractions. A GAL4-UAS system was used to drive homozygous GCAMP expression, causing the muscles of the Drosophila larva to fluoresce when contracting. A stand was designed in order to place a live, crawling larva in a glass capillary tube under a fluorescent microscope and then rotate the tube completely for 360° video footage. Through the combination of the GCAMP expression and the rotatable stand, video of the individual muscle contraction pattern of a crawling …

Locus Of Control And The Age Difference In Free Recall From Episodic Memory, Paul Amrhein, Judith K. Bond, Derek Hamilton

Department of Psychology Faculty Scholarship and Creative Works

The authors investigated the relation of locus of control (LOC) to age differences in free-recall memory performance. Older and younger participants completed P. C. Duttweiler's (1984) Internal Control Index (ICI) and subsequently performed free-recall memory tasks. Compared with the younger participants, the older participants exhibited poorer recall with more intrusions and uncorrected repetition errors as well as reduced categorical clustering. For the older participants with less internal LOC, recall proportion and item-pair associative recall clustering were lower than for the older participants with more internal LOC. By contrast, the younger participants did not exhibit any LOC effects in their recall …

Focal Temperature Change Facilitates The Peak-To-Peak Soleus Hoffmann Reflex And Muscle Response, Bentley Andrew Krause

All-Inclusive List of Electronic Theses and Dissertations

Objective: Cryotherapy is a widely used rehabilitative modality in sports medicine. Cooling joint tissues has been observed to facilitate active exercise following injury. Mechanisms effecting motoneuron recruitment during and following cryotherapy are presumed to be both local and central in nature. Focal cooling facilitates motoncuron pool recruitment and may alter the excitability of motoncurons. The purpose of this investigation was to determine if changes in focal temperature alter the characteristics of the maximum peak-to-peak Hoffmann reflex (Hmax) and muscle response (Mmax). Design and setting: A 4x5 factorial design with repeated measures on time was used in this study. Hmax and …

Effects Of Age On Motor Preparation And Restructuring, Paul Amrhein, Noreen Goggin, George Stelmach

Department of Psychology Faculty Scholarship and Creative Works

Age-related decrements in motor plan restructuring were investigated. In this experiment, older and younger adults performed a discrete aiming task that involved responses that were precued and responses that were modified at the time of an imperative signal. On 75% of the trials, the precue specified the response-stimulus (valid trials) with respect to the movement parameters of the arm (left or right) and direction (toward or away). On the remaining 25% of the trials, the response-stimulus was different from the precue (invalid trials) in that the subject was required to modify a planned movement by changing the arm to be …