Max Kurz

• PhD
• Researcher at Boys Town

The altered sensorimotor cortical dynamics seen in youth with cerebral palsy appear to be tightly coupled with their motor performance errors and uncharacteristic mobility. Very few investigations have used these cortical dynamics as potential biomarkers to predict the extent of the motor performance changes that might be seen after physical therap...

Our understanding of the neurobiology underlying cognitive dysfunction in persons with cerebral palsy is very limited, especially in the neurocognitive domain of visual selective attention. This investigation utilized magnetoencephalography and an Eriksen arrow-based flanker task to quantify the dynamics underlying selective attention in a cohort o...

Prior research has shown that the sensorimotor cortical oscillations are uncharacteristic in persons with cerebral palsy (CP); however, it is unknown if these altered cortical oscillations have an impact on adaptive sensorimotor control. This investigation evaluated the cortical dynamics when the motor action needs to be changed “on-the-fly”. Adult...

Objective The purpose of this investigation was to explore if a physical therapy program involving strength, flexibility, balance, and walking can improve the uncharacteristic gait variability and overall mobility of persons living with multiple sclerosis (pwMS). Design Pre-post design to evaluate the mobility improvements after undergoing 6 weeks...

Elephants are atypical of most quadrupeds in that they maintain the same lateral sequence footfall pattern across all locomotor speeds. It has been speculated that the preservation of the footfall patterns is necessary to maintain a statically stable support polygon. This should be a particularly important constraint in large, relatively slow anima...

Aim To quantify the cervicomedullary motor evoked potentials (CMEPs) at the cervical spinal level in adults with cerebral palsy (CP) and determine if altered CMEPs are linked with upper‐extremity motor function in this population. Method This cross‐sectional study consisted of a cohort of adults with CP (n = 15; mean age = 33 years 5 months [SD =...

Introduction Cerebral Palsy (CP) is the most common neurodevelopmental motor disability, resulting in life-long sensory, perception and motor impairments. Moreover, these impairments appear to drastically worsen as the population with CP transitions from adolescents to adulthood, although the underlying neurophysiological mechanisms remain poorly u...

Objective: Cerebral palsy (CP) is associated with upper extremity motor impairments that are largely assumed to arise from alterations in the supraspinal networks. The objective of this study was to determine if post-activation depression of the spinal H-reflexes is altered in adults with CP and connected with altered upper extremity function. Me...

Persons with cerebral palsy (CP) have impaired mobility that has been attributed to changes in structure and function within the nervous system. The brainstem is a region that plays a critical role in locomotion by connecting the cortex and cerebellum to the spinal cord, yet this region has been largely unstudied in persons with CP. The objective o...

There are numerous clinical reports that youth with cerebral palsy (CP) have proprioceptive, stereognosis and tactile discrimination deficits. The growing consensus is that the altered perceptions in this population are attributable to aberrant somatosensory cortical activity seen during stimulus processing. It has been inferred from these results...

In the largest and most expansive lifespan magnetoencephalography (MEG) study to date (n = 434, 6 to 84 y), we provide critical data on the normative trajectory of resting-state spontaneous activity and its temporal dynamics. We perform cutting-edge analyses to examine age and sex effects on whole-brain, spatially-resolved relative and absolute pow...

Detailed AACPDM 2022 Poster

Background The brain-derived neurotrophic factor (BDNF) protein plays a prominent role in the capacity for neuroplastic change. However, a single nucleotide polymorphism at codon 66 of the BDNF gene results in significant reductions in neuroplastic change. Potentially, this polymorphism also contributes to the weaker somatosensory cortical activity...

Although most neurophysiological studies of persons with cerebral palsy (CP) have been focused on supraspinal networks, recent evidence points toward the spinal cord as a central contributor to their motor impairments. However, it is unclear if alterations in the spinal pathways are also linked to deficits in the sensory processing observed clinica...

There are numerous clinical reports showing that persons with cerebral palsy (CP) have proprioceptive, stereognosis, and tactile discrimination deficits. The current consensus is that these altered perceptions are attributable to aberrant somatosensory cortical activity. It has been inferred from these data that persons with CP do not adequately pr...

Cerebral palsy is the most common pediatric neurological disorder and results in extensive impairment to the sensorimotor system. However, these individuals also experience increased pain perception, resulting in decreased quality of life. In the current study, we utilized magnetoencephalographic brain imaging to examine whether alterations in spon...

Brain-derived neurotrophic factor (BDNF) plays a critical role in the capacity for neuroplastic change. A single nucleotide polymorphism of the BDNF gene is well known to alter the activity-dependent release of the protein and may impact the capacity for neuroplastic change. Numerous studies have shown altered sensorimotor beta event-related desync...

Previous animal models have illustrated that reduced cortical activity in the developing brain has cascading activity-dependent effects on the microstructural organization of the spinal cord. A limited number of studies have attempted to translate these findings to humans with cerebral palsy (CP). Essentially, the aberrations in sensorimotor cortic...

Objective: Our prior magnetoencephalographic (MEG) investigations demonstrate that persons with cerebral palsy (CP) have weaker somatosensory cortical activity than neurotypical (NT) controls, which is associated with reduced muscular strength and mobility. Power training can improve lower extremity isokinetic strength, muscular power, and walking...

Objective To utilize magnetoencephalographic (MEG) brain imaging to examine potential changes in sensorimotor cortical oscillations following therapeutic power training in individuals with cerebral palsy (CP). Design Cohort. Setting Academic medical center. Participants Individuals with CP (N=11; Age=15.9±1.1 yrs; GMFCS I- III) and neurotypical...

Previous animal models have illustrated that reduced cortical activity in the developing brain has cascading activity-dependent effects on the microstructural organization of the spinal cord. A limited number of studies have attempted to translate these findings to humans with cerebral palsy (CP). Essentially, the aberrations in sensorimotor cortic...

Somatosensory cortical activity is altered in individuals with cerebral palsy (CP). However, previous studies have focused on the lower extremities in children with CP and have given less attention to structural changes that may contribute to these alterations. We used a multimodal neuroimaging approach to investigate the relationship between somat...

Cerebral palsy (CP) is the most prevalent pediatric neurologic impairment and is associated with major mobility deficiencies. This has led to extensive investigations of the sensorimotor network, with far less research focusing on other major networks. The aim of this study was to investigate the functional connectivity (FC) of the main sensory net...

Aim To quantify the microstructural differences in the cervical‐thoracic spinal cord of adults with cerebral palsy (CP). Method Magnetic resonance imaging of the proximal spinal cord (C6–T3) was conducted on a cohort of adults with CP (n=13; mean age=31y 11mo, standard deviation [SD] 8y 7mo; range=20y 8mo–47y 6mo; eight females, five males) and po...

Adolescence is a critical period for the development and refinement of several higher-level cognitive functions, including visual selective attention. Clinically, it has been noted that adolescents with cerebral palsy (CP) may have deficits in selectively attending to objects within their visual field. This study aimed to evaluate the neural oscill...

Dynamically allocating neural resources to salient features or objects within our visual space is fundamental to making rapid and accurate decisions. Impairments in such visuospatial abilities have been consistently documented in the clinical literature on individuals with cerebral palsy (CP), although the underlying neural mechanisms are poorly un...

Objective This investigation used magnetoencephalography (MEG) to identify the neurophysiological mechanisms contributing to the altered cognition seen in adults with cerebral palsy (CP). Methods Adults with CP (GMFCS levels I-IV) and demographically-matched controls completed a Sternberg-type working memory task during MEG. Secondarily, they comp...

Key points Individuals with cerebral palsy (CP) have a reduced somatosensory cortical response Somatosensory cortical response strength decreases from adolescence to early adulthood Somatosensory cortical responses in youth with CP are similar to adult controls Individuals with CP may have aberrant maturation of the somatosensory system Abstract N...

Objective It is widely believed that the perinatal brain injuries seen in youth with cerebral palsy (CP) impact neuronal processing of sensory information and the production of leg motor actions during gait. However, very limited efforts have been made to evaluate the connection between neural activity within sensorimotor networks and the altered s...

Objective: To compare the prefrontal cortex activation (PFC) and task performance during single- and dual-task conditions between typically developing (TD) and children with hemiplegic cerebral palsy (HCP). Design: A prospective, comparative design SETTING: Research lab. Participants: Twelve TD children (Age= 6.0 + 1.1 yrs.) and 9 children wit...

Objective To explore if an intensive balance training protocol that incorporated the BrainPort sensory substitution device improves the standing postural balance of children with balance disorders. Methods Eight children with balance disorders received 8-weeks of balance training while using the BrainPort device. Pre- and post-intervention changes...

Despite the growing clinical recognition of visual impairments among people with cerebral palsy (CP), very few studies have evaluated the neurophysiology of the visual circuitry. To this end, the primary aim of this investigation was to use magnetoencephalography and beamforming methods to image the relative change in the alpha-beta and gamma occip...

It is well appreciated that processing of peripheral feedback by the somatosensory cortices plays a prominent role in the control of human motor actions like walking. However, very few studies have actually quantified the somatosensory cortical activity during walking. In this investigation, we used electroencephalography (EEG) and beamforming sour...

Background Children with cerebral palsy (CP) often have altered gait patterns compared to their typically developing peers. These gait patterns are characterized based on sagittal plane kinematic deviations; however, many children with CP also walk with altered transverse plane kinematics. Research Question How do both altered skeletal alignment a...

Adolescents demonstrate increasing mastery of motor actions with age. One prevailing hypothesis is that maturation of the somatosensory system during adolescence contributes to the improved motor control. However, limited efforts have been made to determine if somatosensory cortical processing is different in adolescents during movement. In this st...

Background. The neuroimaging literature on cerebral palsy (CP) has predominantly focused on identifying the structural aberrations (eg, fiber track integrity), with very few studies examining neural activity within the key networks that serve the production of hand movements. Objective. We aimed to start to fill this knowledge gap by using magnetoe...

Date Presented 04/06/19 Although frequently overlooked, children with cerebral palsy may have a visual dysfunction that can impact their occupational performance. Our brain imaging results show that these children have weaker activity in the V5 visual cortices, and this aberrant activity is linked with their altered perception of visual motion. The...

Key points Magnetoencephalography data were acquired during a leg force task in pre‐/post‐practice sessions in adolescents and adults. Strong peri‐movement alpha and beta oscillations were mapped to the cortex. Following practice, performance improved and beta oscillations were altered. Beta oscillations decreased in the sensorimotor cortex in adol...

Cortical visual processing in visual MT/V5 is necessary for tracking movement and performing reliable visuomotor transformations. Although the role of this cortical area is well recognized, the activity of the visual MT/V5 cortical area in children with cerebral palsy (CP) has not been examined nor has its potential role in the atypical motor actio...

Background/Purpose: Dual-task (DT) is defined as simultaneously performing the cognitive and motor task and is important for activities of daily living.1 It is known that the competing cognitive-motor resources in DT deteriorates the task performance.2,3 Evidence suggests that reduced task performance in children with hemiplegic cerebral palsy (HCP...

Cerebral palsy (CP) is a neurological disorder that results in life-long mobility impairments. Musculoskeletal models used to investigate mobility deficits for children with CP often lack subject-specific characteristics such as altered muscle strength, despite a high prevalence of muscle weakness in this population. We hypothesized that incorporat...

Strength training is often prescribed for children with cerebral palsy (CP); however, links between strength gains and mobility are unclear. Nine children (age 14 ± 3 years; GMFCS I-III) with spastic CP completed a 6-week strength-training program. Musculoskeletal gait simulations were generated for four children to assess training effects on muscl...

There is mounting experimental evidence that suggests children with hemiplegic cerebral palsy (HCP) lack the ability to properly plan their motor actions. The purpose of this investigation was to determine how these planning deficits might affect the ability of children with HCP to execute a complex sequence of actions that have different final end...

Background: Action-planning and execution deficits in children with hemiplegic cerebral palsy (HCP) are potentially due to deficits in the integration of sensory information, such as vision, with motor output. Aims: To determine differences in anticipatory visual patterns in children with HCP compared to typically developing (TD) children, and t...

Numerous studies of motor control have confirmed beta and gamma oscillations in the primary motor cortices during basic movements. These responses include a robust beta decrease that precedes and extends through movement onset, a transient gamma response that coincides with the movement, and a post-movement beta rebound (PMBR) response that occurs...

Key points: Several behavioral studies have shown the sensory perceptions are reduced during movement; yet the neurophysiological reason is not clear. Participants underwent stimulation of the median nerve while either sitting quietly (i.e., passive stimulation condition) or performing haptic exploration of a ball with the left hand. MEG brain ima...

en This commentary is on the original article by Franckx et al.

During active movement the somatosensory cortical responses are often attenuated. This attenuation is referred to as movement-related sensory gating. It is well known that patients with multiple sclerosis (MS) have sensory processing deficits, and recent work has also suggested that these patients display impaired motor control of the ankle muscula...

Purpose: To determine the changes in the prefrontal cortical (PFC) activation following hand-arm bimanual intensive therapy (HABIT) in children with hemiplegic cerebral palsy (HCP). Methods: Nine children with HCP and 15 children who were developing typically participated in the study. Children with HCP received 50 hours of HABIT. We assessed pr...

Although it is well appreciated that practicing a motor task updates the associated internal model, it is still unknown how the cortical oscillations linked with the motor action change with practice. The present study investigates the short-term changes (e.g., fast motor learning) in the alpha and beta event related desynchronizations (ERD) associ...

Abstract. The primary aim of the study was to explore the prefrontal cortical (PFC) activation while performing a shape-matching motor task in children with hemiplegic cerebral palsy (HCP) as compared with typically developing (TD) children. Fifteen TD children (age 1⁄4 5.9 1.1 years) and 12 children with HCP (age 1⁄4 6.8 2.9 years) were included....

BODY: Purpose/Hypothesis : Children with HCP have difficulty planning the discrete motor actions performed with their hemiplegic arm.1-6 It is currently unknown if the discrete motor planning deficits have a cascading effect on the ability of children with HCP to plan a sequence of movements. The purposes were to determine differences in kinematic...

Purpose/Hypothesis : Impaired motor performance in children with hemiplegic cerebral palsy (HCP) is related to deficits in planning goal-directed actions.1,2 Studies investigating planning deficits in children with HCP suggested possible deficits in the integration of sensory information, such as vision, with motor output in children with HCP.3,4 T...

Shortly after movement termination, there is a strong increase or resynchronization of the beta rhythm (15–30 Hz) across the sensorimotor network of humans, known as the post-movement beta rebound (PMBR). This response has been associated with active inhibition of the motor network following the completion of a movement, sensory afferentation of th...

When identical stimuli are presented in rapid temporal succession, neural responses to the second stimulation are often weaker than that observed for the first. This phenomenon is termed sensory gating and is believed to be an adaptive feature that helps prevent higher-order cortical centers from being flooded with unnecessary information. Recently...

We currently have a substantial knowledge gap in our understanding of the neurophysiological underpinnings of the sensory perception deficits often reported in the clinic for children with cerebral palsy (CP). In this investigation, we have begun to address this knowledge gap by using magnetoencephalography (MEG) brain imaging to evaluate the senso...

Multiple sclerosis (MS) is a demyelinating disease that results in a broad array of symptoms, including impaired motor performance. How such demyelination of fibers affects the inherent neurophysiological activity in motor circuits, however, remains largely unknown. Potentially, the movement errors associated with MS may be due to imperfections in...

The neuroimaging literature on cerebral palsy (CP) has predominantly focused on identifying structural aberrations within the white matter (e.g., fiber track integrity), with very few studies examining neural activity within the key networks that serve the production of motor actions. The current investigation used high-density magnetoencephalograp...

Background: Individuals with multiple sclerosis (MS) often have limited mobility that is thought to be due to the neuromuscular impairments of the ankle. Greater isometric motor control of the ankle has been associated with better standing postural balance but its relationship to mobility is less understood. The objectives of this investigation we...

Musculoskeletal modeling and simulation techniques have been used to gain insights into movement disabilities for many populations, such as ambulatory children with cerebral palsy (CP). The individuals who can benefit from these techniques are often limited to those who can walk without assistive devices, due to challenges in accurately modeling th...

There is currently a void in the scientific literature on the cortical beta oscillatory activity that is associated with the production of leg motor actions. In addition, we have limited data on how these cortical oscillations may progressively change as a function of development. This study began to fill this vast knowledge gap by using high-densi...

Sensory gating is a phenomenon in which neuronal responses to subsequent similar stimuli are suppressed when they occur in a series. • It is thought to represent a mechanism by which redundant stimuli are partially "filtered out," preventing excessive environmental stimulation from overloading shared neural resources. • Gating has been demonstrated...

Evaluating the effects of estimating ankle foot orthosis mechanical properties on musculoskeletal gait simulations for children with cerebral palsy

Individuals with multiple sclerosis (MS) typically walk slower, have reduced cadences and shorter step lengths. While these spatiotemporal gait alterations have been thought to be due to decreased power generation at the ankle, the distribution of mechanical work across the ankle, knee and hip joints during walking is not well understood. By quanti...

Objective: To evaluate the mobility and postural balance improvements that could be achieved in a cohort of persons with multiple sclerosis (MS) that participated in a motor adaptation protocol (MAC) and a cohort of persons with MS who participated in a therapeutic exercise protocol (TEC). Design: A cohort design, where subjects were evaluated b...

The goal of this pilot study was to characterize the effects of gait training on the capacity of muscles to produce body accelerations, and relate these changes to mobility improvements seen in children with cerebral palsy (CP). Five children (14 years ± 3 years; GMFCS I-II) with spastic diplegic CP participated in a six-week gait training program....

Evaluating the effects of estimating ankle foot orthosis mechanical properties on musculoskeletal gait simulation results for children with cerebral palsy

Objective: To quantify the precision of the steady-state isometric control of the ankle plantarflexors musculature of individuals with multiple sclerosis (MS), and to evaluate if the precision is related to the mobility impairments. Methods: Individuals with MS and healthy adults performed a submaximal steady-state isometric contraction with the...

While the development and execution of upper extremity motor plans have been well explored, little is known about how individuals plan and execute rapid, goal-directed motor tasks with the lower extremities. Furthermore, the amount of time needed to integrate the proper amount of visual and proprioceptive feedback before being able to accurately ex...

The neuromuscular impairments seen in the ankle plantarflexors have been identified as a primary factor that limits the mobility and standing postural balance of individuals with multiple sclerosis (MS). However, few efforts have been made to find effective treatment strategies that will improve the ankle plantarflexor control. Our objective was to...

Numerous clinical investigations have reported that children with cerebral palsy (CP) have tactile discrimination deficits that likely limit their ability to plan and manipulate objects. Despite this clinical awareness, we still have a substantial knowledge gap in our understanding of the neurological basis for these tactile discrimination deficits...

The noted disruption of thalamocortical connections and abnormalities in tactile sensory function has resulted in a new definition of cerebral palsy (CP) that recognizes the sensorimotor integration process as central to the motor impairments seen in these children. Despite this updated definition, the connection between a child's motor impairments...

Purpose: Children with cerebral palsy (CP) often use a crouch gait pattern that has disturbances in the knee joint kinematics. Although the length and rate of lengthening of the hamstring musculature have been speculated to be the reason that these disturbances are not adequately dissipated, this relationship has not been adequately explored. The...

Children who receive treatment for medulloblastoma have a high survival rate, but also a high likelihood of developing posterior fossa syndrome, a condition that includes devastating balance and motor problems. This case series used 2 novel neuromodulation devices in conjunction with an intensive physical therapy intervention for 2 children who wer...

Objective: The primary aim of this exploratory investigation was to determine if there are differences in cortical activation of children with spastic diplegic cerebral palsy (CP) and typically developing children during gait. Methods: Functional near-infrared spectroscopy was used to measure the concentration of oxygenated hemoglobin that was p...

This commentary is on the original article by Schroeder et al. on pages 1172–1179 of this issue.

Parkinson's disease (PD) is a progressive debilitating neurodegenerative disorder clinically manifest by motor, posture and gait abnormalities. Human neurophysiological studies recording local field potentials within the subthalamic nucleus and scalp-based electroencephalography have shown pathological beta synchrony throughout the basal ganglia-th...

AimThis investigation used magnetoencephalography (MEG) to examine the neural oscillatory responses of the sensorimotor cortices during the motor planning and movement execution stages of children with typical development and children with cerebral palsy (CP). Method The study involved 13 children with CP (nine males, four females; mean [SD] age 14...

Cerebral palsy (CP) results from a perinatal brain injury that often results in sensory impairments and greater errors in motor performance. Although these impairments have been well catalogued, the relationship between sensory processing networks and errors in motor performance has not been well explored. Children with CP and typically developing...

Acknowledgements This work was supported by Section on Pediatrics of the American Physical Therapy Association

Bimanual movements can be performed by flexing and extending the target effectors (e.g., hand muscles) in unison, or by flexing units on one side in unison with extension of the same units on the opposite side. The former movement patterns are generally referred to as in-phase or parallel, whereas the latter patterns are often termed anti-phase mov...

Children with balance impairments have an increased amount of variability in the sway of the center of pressure (COP) during standing. Limited efforts have been made to quantify the nature of the variability. This exploratory investigation examined the deterministic and stochastic features that comprise the time-dependent postural sway variability...

ABSTRACT The aim of this investigation was to determine if body-weight-supported (BWS) overground gait training has the potential to improve the walking abilities of children and youth with childhood onset motor impairments and intellectual disabilities. Eight participants (mean age of 16.3 years) completed 12 weeks of BWS overground gait training...