Cortical Mechanisms of Human Pelvic Floor Muscle Synergies

The human pelvic floor is an anatomically, functionally, and morphologically complex region that is associated with many disorders such as chronic prostatitis/pelvic pain syndrome (CPPS), chronic low back pain, and urinary incontinence. The purpose of this dissertation was to explore the cortical mechanisms that underlie human pelvic floor muscle synergies. Our first original experiment involved the study of 20 healthy male controls who were instructed to perform a variety of muscle tasks presumed to be associated with pelvic floor muscle synergies. Surface electromyography (EMG) method was used to detect timing onsets, as well as activation patterns of the pelvic floor, gluteus maximus, and first dorsal interosseous muscles. Functional magnetic resonance imaging (fMRI) was used to measure blood oxygenation density levels (BOLD) in the brain while subjects performed various prime mover tasks. Our second original experiment involved another set of 10 healthy male subjects who were trained to perform a complex synergy breaking/decoupling task that was confirmed with EMG. They repeated the coupling motor task (gluteal activation) as well as the more complex motor decoupling task while being scanned with fMRI, so that BOLD signals could be compared. The first experiment revealed evidence of cortically facilitated synergy of the pelvic floor muscles and the second experiment revealed that complex motor tasks such as the breaking of a cortically facilitated muscle synergy involves BOLD signals in the brain known to be involved with interoception

Altered resting state neuromotor connectivity in men with chronic prostatitis/chronic pelvic pain syndrome: A MAPP: Research Network Neuroimaging Study.

Brain network activity associated with altered motor control in individuals with chronic pain is not well understood. Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) is a debilitating condition in which previous studies have revealed altered resting pelvic floor muscle activity in men with CP/CPPS compared to healthy controls. We hypothesized that the brain networks controlling pelvic floor muscles would also show altered resting state function in men with CP/CPPS. Here we describe the results of the first test of this hypothesis focusing on the motor cortical regions, termed pelvic-motor, that can directly activate pelvic floor muscles. A group of men with CP/CPPS (N = 28), as well as group of age-matched healthy male controls (N = 27), had resting state functional magnetic resonance imaging scans as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study. Brain maps of the functional connectivity of pelvic-motor were compared between groups. A significant group difference was observed in the functional connectivity between pelvic-motor and the right posterior insula. The effect size of this group difference was among the largest effect sizes in functional connectivity between all pairs of 165 anatomically-defined subregions of the brain. Interestingly, many of the atlas region pairs with large effect sizes also involved other subregions of the insular cortices. We conclude that functional connectivity between motor cortex and the posterior insula may be among the most important markers of altered brain function in men with CP/CPPS, and may represent changes in the integration of viscerosensory and motor processing

Screening for Head, Neck, and Shoulder Pathology in Patients with Upper Extremity Signs and Symptoms

Narrative Review: Conditions of the head, neck, thorax, and shoulder may occur simultaneously with arm pathology or produce symptoms perceived by the patient to originate in the elbow, wrist, or hand. Identification of the tissue disorder and associated impairments, followed by matching the rehabilitative intervention to address these issues, leads to optimal outcomes. With this goal in mind, the hand therapist needs to recognize clinical findings that signal potentially serious medical conditions of the brain, cervical region, chest, or shoulder. Additionally, less serious but potentially debilitating, musculoskeletal or neurogenic pain from proximal sources must also be differentiated from somatic pain originating in the elbow, wrist, or hand so that the clinician can decide to further examine and intervene or refer to an appropriate health care provider. This article describes clinical findings that suggest the presence of serious medical pathology in the head, neck, or thorax and presents a screening algorithm to assist in discriminating pain derived from local structures in the distal arm from referred pain originating in the more proximal regions of the shoulder, thorax, neck, or brain

The Motor Cortical Representation of a Muscle is Not Homogeneous in Brain Connectivity

Functional connectivity patterns of the motor cortical representational area of single muscles have not been extensively mapped in humans, particularly for the axial musculature. Functional connectivity may provide a neural substrate for adaptation of muscle activity in axial muscles that have both voluntary and postural functions. The purpose of this study was to combine brain stimulation and neuroimaging to both map the cortical representation of the external oblique (EO) in primary motor cortex (M1) and supplementary motor area (SMA), and to establish the resting-state functional connectivity associated with this representation. Motor evoked potentials were elicited from the EO muscle in stimulation locations encompassing M1 and SMA. The coordinates of locations with the largest motor evoked potentials were confirmed with task-based fMRI imaging during EO activation. The M1 and SMA components of the EO representation demonstrated significantly different resting-state functional connectivity with other brain regions: the SMA representation of the EO muscle was significantly more connected to the putamen and cerebellum, and the M1 representation of the EO muscle was significantly more connected to somatosensory cortex and the superior parietal lobule. This study confirms the representation of a human axial muscle in M1 and SMA, and demonstrates for the first time that different parts of the cortical representation of a human axial muscle have resting-state functional connectivity with distinct brain regions. Future studies can use the brain regions of interest we have identified here to test the association between resting-state functional connectivity and control of the axial muscles

Altered resting state neuromotor connectivity in men with chronic prostatitis/chronic pelvic pain syndrome: A MAPP: Research Network Neuroimaging Study.

Brain network activity associated with altered motor control in individuals with chronic pain is not well understood. Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) is a debilitating condition in which previous studies have revealed altered resting pelvic floor muscle activity in men with CP/CPPS compared to healthy controls. We hypothesized that the brain networks controlling pelvic floor muscles would also show altered resting state function in men with CP/CPPS. Here we describe the results of the first test of this hypothesis focusing on the motor cortical regions, termed pelvic-motor, that can directly activate pelvic floor muscles. A group of men with CP/CPPS (N = 28), as well as group of age-matched healthy male controls (N = 27), had resting state functional magnetic resonance imaging scans as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study. Brain maps of the functional connectivity of pelvic-motor were compared between groups. A significant group difference was observed in the functional connectivity between pelvic-motor and the right posterior insula. The effect size of this group difference was among the largest effect sizes in functional connectivity between all pairs of 165 anatomically-defined subregions of the brain. Interestingly, many of the atlas region pairs with large effect sizes also involved other subregions of the insular cortices. We conclude that functional connectivity between motor cortex and the posterior insula may be among the most important markers of altered brain function in men with CP/CPPS, and may represent changes in the integration of viscerosensory and motor processing

Altered resting state neuromotor connectivity in men with chronic prostatitis/chronic pelvic pain syndrome: A MAPP

Brain network activity associated with altered motor control in individuals with chronic pain is not well understood. Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) is a debilitating condition in which previous studies have revealed altered resting pelvic floor muscle activity in men with CP/CPPS compared to healthy controls. We hypothesized that the brain networks controlling pelvic floor muscles would also show altered resting state function in men with CP/CPPS. Here we describe the results of the first test of this hypothesis focusing on the motor cortical regions, termed pelvic-motor, that can directly activate pelvic floor muscles. A group of men with CP/CPPS (N = 28), as well as group of age-matched healthy male controls (N = 27), had resting state functional magnetic resonance imaging scans as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study. Brain maps of the functional connectivity of pelvic-motor were compared between groups. A significant group difference was observed in the functional connectivity between pelvic-motor and the right posterior insula. The effect size of this group difference was among the largest effect sizes in functional connectivity between all pairs of 165 anatomically-defined subregions of the brain. Interestingly, many of the atlas region pairs with large effect sizes also involved other subregions of the insular cortices. We conclude that functional connectivity between motor cortex and the posterior insula may be among the most important markers of altered brain function in men with CP/CPPS, and may represent changes in the integration of viscerosensory and motor processing