Sensorimotor Function In Patients Research Articles

A Comparison of the Effects of Stochastic Resonance Therapy, Whole-Body Vibration, and Balance Training on Pain Perception and Sensorimotor Function in Patients With Chronic Nonspecific Neck Pain: Protocol for a Randomized Controlled Trial.

BackgroundNeck pain is a prevalent pathological condition, and together with low back pain, it presents as the leading cause of years lived with disability worldwide in 2015 and continues to contribute substantially to the global burden of disease.ObjectiveThis study will investigate and compare the effects of stochastic resonance therapy (SRT), whole-body vibration (WBV), and balance training (BLT) in the management of chronic nonspecific neck pain.MethodsIn total, 45 participants with chronic neck pain will be randomly allocated into SRT, WBV, and BLT groups. Pain intensity, pressure pain threshold, neck disability, and cervical joint position sense will be measured before, immediately after, and 15 minutes after the first intervention session and after 4 weeks of intervention. A follow-up postintervention measurement would be taken after 4 weeks. The SRT group will train on an SRT device (SRT Zeptor Medical plus noise, Zeptoring). The WBV group will train on a Galileo vibration device (Novotec Medical), while the BLT group will perform balance exercises. All participants shall train 3 times a week for a period of 4 weeks. Mixed ANOVA will be used to determine the main and effects of interactions within (before intervention, post intervention 1, post intervention 2, post intervention 3, and follow-up) and between (SRT, WBV, and BLT) factors on the study outcome variables.ResultsRecruitment of participants started in May 2021, and as of May 2022, a total of 20 patients have been enrolled in the study. All participants are expected to have completed the trial by the end of 2022, and data analysis will commence thereafter.ConclusionsThe outcome of this study will shed closer light on the effects of SRT, WBV, and BLT on pain and function in patients with chronic neck pain.Trial RegistrationGerman Clinical Trials Register DRKS00023881; https://tinyurl.com/ycxuhj37International Registered Report Identifier (IRRID)DERR1-10.2196/34430

Virtual Reality Training Using Nintendo Wii Games for Patients With Stroke: Randomized Controlled Trial

BackgroundStroke is a leading cause of disability. It is difficult to devise an optimal rehabilitation plan once stroke survivors are back home. Conventional rehabilitative therapies are extensively used in patients with stroke to recover motor functioning and disability, but these are arduous and expensive. Virtual reality (VR) video games inspire patients to get involved in their therapeutic exercise routine in a fun way. VR in the form of games provides a fruitful, secure, and challenging learning environment for motor control and neural plasticity development in rehabilitation. The effects of upper limb sensorimotor functioning and balance are the main focus of this trial.ObjectiveThe aim of this study is to compare the effects of VR training and routine physical therapy on balance and upper extremity sensorimotor function in patients with stroke.MethodsIt was a single assessor-blinded randomized clinical trial. A total of 74 participants with their first chronic stroke were included and rehabilitated in a clinical setting. The lottery method was used to randomly assign patients to either the VR group (n=37) or the routine physical therapy group (n=37). The VR group received a 1-hour session of VR training for 3 weekdays over 6 weeks, and the routine physical therapy group received different stretching and strengthening exercises. The outcome measuring tools were the Berg Balance Scale for balance and the Fugl-Meyer Assessment (upper extremity) scale for sensorimotor, joint pain, and range assessment. The assessment was done at the start of treatment and after the 6 weeks of intervention. Data analysis was done using SPSS 22.ResultsThe trial was completed by 68 patients. A significant difference between the two groups was found in the Berg Balance Scale score (P<.001), Fugl-Meyer Assessment for motor function (P=.03), and Fugl-Meyer Assessment for joint pain and joint range (P<.001); however, no significant difference (P=.19) in the Fugl-Meyer Assessment for upper extremity sensation was noted.ConclusionsVR training is helpful for improving balance and function of the upper extremities in the routine life of patients with stroke; although, it was not found to be better than conventional training in improving upper limb sensation. VR training can be a better option in a rehabilitation plan designed to increase functional capability.Trial RegistrationIranian Registry of Clinical Trials RCT20190715044216N1; https://www.irct.ir/user/trial/40898/view

Association of visual motor processing and social cognition in schizophrenia

Patients with schizophrenia have difficulties in social cognitive domains including emotion recognition and mentalization, and in sensorimotor processing and learning. The relationship between social cognitive deficits and sensorimotor function in patients with schizophrenia remains largely unexplored. With the hypothesis that impaired visual motor processing may decelerate information processing and subsequently affects various domains of social cognition, we examined the association of nonverbal emotion recognition, mentalization, and visual motor processing in schizophrenia. The study examined mentalization using the verbal subset of the Chinese version of Theory of Mind (CToM) Task, an equivalent task of the Faux Pas Test; emotion recognition using the Diagnostic Analysis of Nonverbal Accuracy 2-Taiwan version (DANVA-2-TW), and visual motor processing using a joystick tracking task controlled for basic motor function in 34 individuals with chronic schizophrenia in the community and 42 healthy controls. Patients with schizophrenia had significantly worse performance than healthy controls in social cognition, including facial, prosodic emotion recognition, and mentalization. Visual motor processing was also significantly worse in patients with schizophrenia. Only in patients with schizophrenia, both emotion recognition (mainly in prosodic modality, happy, and sad emotions) and mentalization were positively associated with their learning capacity of visual motor processing. These findings suggest a prospective role of sensorimotor function in their social cognitive deficits. Despite that the underlying neural mechanism needs further research, our findings may provide a new direction for restoration of social cognitive function in schizophrenia by enhancing visual motor processing ability.

Differential patterns of interhemispheric functional connectivity between AQP4-optic neuritis and MOG-optic neuritis: a resting-state functional MRI study.

Several neuroimaging studies demonstrated that optic neuritis (ON) leads to functional and anatomical architecture changes in the brain. The alterations of interhemispheric functional connectivity (IFC) in patients with AQP4-ON and myelin oligodendrocyte glycoprotein (MOG)-ON are not well understood. To investigate the differential patterns of VMHC in patients with AQP4-ON and MOG-ON. Twenty-one patients with AQP4-ON, 11 patients with MOG-ON, and 34 healthy controls underwent resting-state MRI scans. One-way ANOVA was used to identify regions in which the zVMHC differed among the three groups. Post hoc two-sample t-tests were then conducted to compare zVMHC values between pairs of groups. Pearson correlation analysis was conducted to reveal relationships between mean zVMHC values and clinical variables in the AQP4-ON and MOG-ON groups. The results revealed significant differences in zVMHC values in the PreCG among the three groups. Compared to the control group: the AQP4-ON group showed significantly lower VMHC values in the superior temporal gyrus, inferior frontal gyrus, and PreCG; and the MOG-ON group showed significantly higher zVMHC values in the PostCG. Compared to the AQP4-ON group, the MOG-ON group showed significantly lower zVMHC values in the PreCG/PostCG (voxel-level P<0.01, GRF correction, cluster-level P<0.05). Patients with AQP4-ON and those with MOG-ON showed abnormal VMHC in the motor cortices, sensorimotor cortices, and frontal lobe, possibly indicating impaired sensorimotor function in patients with ON. Moreover, differential patterns of VMHC in patients with AQP4-ON, compared to patients with MOG-ON, might serve as a clinical indicator for classification of ON.

Effects of chronic ankle instability on cutaneous reflex modulation during walking.

Chronic ankle instability (CAI) is characterized by persistent giving way at the ankle following an acute lateral ankle sprain and is associated with an early onset of osteoarthritis. Researchers have reported that the cutaneous afferent pathway from certain leg muscles is modified in people with CAI while in a seated position. However, we do not know if these reflex modulations persist during functional activities. The purpose of this study was to further explore sensorimotor function in patients with CAI by analyzing cutaneous reflex modulation during gait. CAI (n = 11) and uninjured control (n = 11) subjects walked on a treadmill at 4km/h and received non-noxious sural nerve stimulations at eight different time points during the gait cycle. Net electromyographic responses from four lower leg muscles were quantified 80-120ms after stimulation for each phase of the gait cycle and compared between groups. We found that cutaneous reflex responses between groups were largely similar from the late stance to late swing phases, but uninjured control subjects, and not CAI subjects, experienced significant suppression in the medial gastrocnemius and lateral gastrocnemius muscles during the early stance phase of the gait cycle. Our results indicate that people with CAI lack a protective unloading response in the triceps surae following high-intensity sural nerve stimulation during the early stance phase of the gait cycle. Evaluating cutaneous reflex modulations may help to identify neural alterations in the reflex pathways that contribute to functional deficits in those with CAI.

Evidence for an association of gut microbial Clostridia with brain functional connectivity and gastrointestinal sensorimotor function in patients with irritable bowel syndrome, based on tripartite network analysis

Background and aimsEvidence from preclinical and clinical studies suggests that interactions among the brain, gut, and microbiota may affect the pathophysiology of irritable bowel syndrome (IBS). As disruptions in central and peripheral serotonergic signaling pathways have been found in patients with IBS, we explored the hypothesis that the abundance of serotonin-modulating microbes of the order Clostridiales is associated with functional connectivity of somatosensory brain regions and gastrointestinal (GI) sensorimotor function.MethodsWe performed a prospective study of 65 patients with IBS and 21 healthy individuals (controls) recruited from 2011 through 2013 at a secondary/tertiary care outpatient clinic in Sweden. Study participants underwent functional brain imaging, rectal balloon distension, a nutrient and lactulose challenge test, and assessment of oroanal transit time within a month. They also submitted stool samples, which were analyzed by 16S ribosomal RNA gene sequencing. A tripartite network analysis based on graph theory was used to investigate the interactions among bacteria in the order Clostridiales, connectivity of brain regions in the somatosensory network, and GI sensorimotor function.ResultsWe found associations between GI sensorimotor function and gut microbes in stool samples from controls, but not in samples from IBS patients. The largest differences between controls and patients with IBS were observed in the Lachnospiraceae incertae sedis, Clostridium XIVa, and Coprococcus subnetworks. We found connectivity of subcortical (thalamus, caudate, and putamen) and cortical (primary and secondary somatosensory cortices) regions to be involved in mediating interactions among these networks.ConclusionsIn a comparison of patients with IBS and controls, we observed disruptions in the interactions between the brain, gut, and gut microbial metabolites in patients with IBS—these involve mainly subcortical but also cortical regions of brain. These disruptions may contribute to altered perception of pain in patients with IBS and may be mediated by microbial modulation of the gut serotonergic system.

Resting-State Functional Magnetic Resonance Imaging Connectivity of the Brain Is Associated with Altered Sensorimotor Function in Patients with Cervical Spondylosis

To determine the relationship between functional connectivity (FC) using resting-state functional magnetic resonance imaging (MRI) and neurological impairment in patients with cervical spondylosis and healthy controls. A total of 24 patients with cervical spondylosis with or without myelopathy and 17 neurologically intact, healthy volunteer subjects were prospectively enrolled in a cross-sectional study involving observational MRI and evaluation of neurological function using the modified Japanese Orthopedic Association (mJOA) score. Seed-to-seed connectivity and seed-to-voxel connectivity on functional MRI data were performed using a general linear model of connectivity with respect to age and mJOA score. Increased FC was observed with increasing neurological impairment in patients with cervical stenosis within sensorimotor areas, including precentral gyrus, postcentral gyrus, and supplemental motor regions, using both seed-to-seed and seed-to-voxel analyses. The anterior cingulate showed increasing connectivity with the supplemental motor area, thalamus, and cerebellum with increasing neurological function. Similarly, the thalamus, cerebellum, and putamen presented with increasing connectivity to both the bilateral precuneus and the posterior cingulate with an increasing mJOA score. Patients with cervical spondylosis exhibiting neurological impairment experience changes in brain connectivity similar to that of patients with chronic traumatic spinal cord injury. These results suggest an increase in FC within sensorimotor regions with increasing neurological impairment and decreased connectivity between the cerebellum, putamen, and thalamus to the anterior and posterior cingulate and frontal lobe regions.

Early self-managed focal sensorimotor rehabilitative training enhances functional mobility and sensorimotor function in patients following total knee replacement: a controlled clinical trial

Objective: To assess the effects of early self-managed focal sensorimotor training compared to functional exercise training after total knee replacement on functional mobility and sensorimotor function. Design: A single-blind controlled clinical trial. Setting: University Hospital of Rion, Greece. Subjects: A total of 52 participants following total knee replacement. Outcome measures: The primary outcome was the Timed Up and Go Test and the secondary outcomes were balance, joint position error, the Knee Outcome Survey Activities of Daily Living Scale, and pain. Patients were assessed on three separate occasions (presurgery, 8 weeks post surgery, and 14 weeks post surgery). Intervention: Participants were randomized to either focal sensorimotor exercise training (experimental group) or functional exercise training (control group). Both groups received a 12-week home-based programme prescribed for 3–5 sessions/week (35–45 minutes). Results: Consistently greater improvements (F2,98 = 4.3 to 24.8; P < 0.05) in group mean scores favour the experimental group compared to the control group: Timed Up and Go (7.8 ± 2.9 seconds vs. 4.6 ± 2.6 seconds); balance (2.1 ± 0.9° vs. 0.7 ± 1.2°); joint position error (13.8 ± 7.3° vs. 6.2 ± 9.1°); Knee Outcome Survey Activities of Daily Living Scale (44.2 ± 11.3 vs. 26.1 ± 11.4); and pain (5.9 ± 1.3 cm vs. 4.6 ± 1.1 cm). Patterns of improvement for the experimental group over time were represented by a relative effect size range of 1.3–6.5. Conclusions: Overall, the magnitude of improvements in functional mobility and sensorimotor function endorses using focal sensorimotor training as an effective mode of rehabilitation following knee replacement.

Objective Assessment of Knee Proprioception and Sensorimotor Function in Patients with Primary Gonarthrosis before and after Knee Replacement.

The sensorimotor system is a complicated tool allowing for maintaining body balance and responding to changing environmental conditions to prevent injury. It is difficult to objectively assess the function of balance control mechanisms due to the multidimensional nature of the sensorimotor system and multitude of variables that may interfere with the measurement. The function of the sensorimotor system is considerably compromised in osteoarthritis, including gona-rthro-sis. The knee is the second most common location of osteoarthritis, after the hip, and total or partial replacement surgery of the knee joint represents the therapy of choice in advanced stages of the condition. As average life expectancy increases and state-of-the art medical technology develops, the number of total knee replacement surgeries is increasing dramatically and the re-education of the sensorimotor system is of fundamental impo-rtance for restoring function in the patients. This paper describes the current methods for objective assessment of proprioception, sensorimotor function and balance in the knee. The current literature is also reviewed to discuss the use of such examinations in pa-tients with gonarthrosis before and after knee replacement surgery.

Multimodal assessment of sensorimotor shoulder function in patients with untreated anterior shoulder instability and asymptomatic handball players.

Functional evaluation of sensorimotor function of the shoulder joint is important for guidance of sports-specific training, prevention and rehabilitation of shoulder instability. Such assessment should be multimodal and comprise all qualities of sensorimotor shoulder function. This study evaluates feasibility of such multimodal assessment of glenohumeral sensorimotor function in patients with shoulder instability and handball players. Nine patients with untreated anterior instability of their dominant shoulder and 15 asymptomatic recreational handball players performed proprioceptive joint position sense and dynamic stabilization evaluations on an isokinetic device, as well as a functional throwing performance task. Outcome measures were analysed individually and equally weighted in a Shoulder-Specific Sensorimotor Index (S-SMI). Finally, isokinetic strength evaluations were conducted. We observed comparable sensorimotor functions of unstable dominant shoulders compared to healthy, contralateral shoulders (e.g. P=0.59 for S-SMI). Handball players demonstrated superior sensorimotor function of their dominant shoulders exhibiting a significantly higher throwing performance and S-SMI (P<0.001 and P=0.002, respectively), but comparable internal rotator peak torques for both shoulders (P>0.22). The present study proves feasibility of multimodal assessment of shoulder sensorimotor function in overhead athletes and patients with symptomatic anterior shoulder instability. Untreated shoulder instability led to a loss of dominance-related sensorimotor superiority indicating functional internal rotation deficiency. Dominant shoulders of handball players showed a superior overall sensorimotor function but weakness of dominant internal rotation constituting a risk factor for occurrence of posterior superior impingement syndrome. The S-SMI could serve as a diagnostic tool for guidance of sports-specific training, prevention and rehabilitation of shoulder instability.

Effect of Proprioceptive Neuromuscular Facilitation (PNF) in Improving Sensorimotor Function in Patients with Diabetic Neuropathy Affecting Lower Limbs

Background: Diabetic Mellitus is a group of metabolic disease characterized by hyperglycaemia resulting from defects in insulin secretion, insulin action or both. Distal Sensorimotor Polyneuropathy is the most common complication of diabetes which mainly affects the lower limbs. Most of the studies aimed at individually increasing muscle strength or sensation but not on overall performance enhancements of the diabetic lower limbs. The evidence supporting the effectiveness of PNF in diabetic neuropathic patients is scarce.Methods: 30 patients, with age between 50 to 70 years, diagnosed with Diabetic Sensorimotor Polyneuropathy (DSP) were selected from the department of Medicine and department of Neurosurgery Guru Gobind Singh Medical College and Hospital. Patients were evaluated at the beginning and at the end of the intervention using Diabetic Neuropathy Examination scores. Patients received 3 sets of exercises one hour/day with 3 days/week for 3 months. Each set of exercises consists of 5 repetitions of PNF patterns (alternate day) and techniques.Results: D1 & D2 patterns of PNF are effective in improving both motor and sensory functions of diabetic patients with neuropathic symptoms. Improvement in muscle strength, reflex and sensations occurred to a greater extent after the treatment of three months in these subjects. This study shows that PNF patterns were effective at enhancing sensorimotor problems of lower limbs.Conclusion: This study concluded that PNF is found to be effective in improving sensorimotor functions of diabetic neuropathic patients affecting lower limbs.

Neuronal plasticity mechanisms induced by brain-machine interfaces: connecting brain to artificial neural network

Brain-machine interfaces, also known as Brain-Computer Interfaces (BCI), are devices that connect the brain to a computer. In the last decade it is been used to investigate the restore of sensorimotor function in patients with cortical damage. Some evidence supports that the results obtained in the research using BCIs in the treatment of these patients are directly dependent on plasticity mechanisms very similar to those observed in learning and memory tasks. Recent studies have been making use of Artificial Neural Networks (ANN) to classify signal patterns throughout neuronal circuits in order to command movements . In this review, we attempted to make a survey on the available data in the literature on this topic in order to gather the most relevant evidence of such mechanisms and the role of ANN on human brain neuronal input decoding compared to other data processing techniques.

Effects of sensorimotor training volume on recovery of sensorimotor function in patients following lower limb arthroplasty.

BackgroundSensorimotor function is degraded in patients after lower limb arthroplasty. Sensorimotor training is thought to improve sensorimotor skills, however, the optimal training stimulus with regard to volume, frequency, duration, and intensity is still unknown. The aim of this study, therefore, was to firstly quantify the progression of sensorimotor function after total hip (THA) or knee (TKA) arthroplasty and, as second step, to evaluate effects of different sensorimotor training volumes.Methods58 in-patients during their rehabilitation after THA or TKA participated in this prospective cohort study. Sensorimotor function was assessed using a test battery including measures of stabilization capacity, static balance, proprioception, and gait, along with a self-reported pain and function. All participants were randomly assigned to one of three intervention groups performing sensorimotor training two, four, or six times per week. Outcome measures were taken at three instances, at baseline (pre), after 1.5 weeks (mid) and at the conclusion of the 3 week program (post).ResultsAll measurements showed significant improvements over time, with the exception of proprioception and static balance during quiet bipedal stance which showed no significant main effects for time or intervention. There was no significant effect of sensorimotor training volume on any of the outcome measures.ConclusionWe were able to quantify improvements in measures of dynamic, but not static, sensorimotor function during the initial three weeks of rehabilitation following TKA/THA. Although sensorimotor improvements were independent of the training volume applied in the current study, long-term effects of sensorimotor training volume need to be investigated to optimize training stimulus recommendations.Trial registrationClinical trial registration number: DRKS00007894

Neck muscle vibration can improve sensorimotor function in patients with neck pain

Background contextPeople with neck pain display a diminished joint position sense and disturbed postural control, which is thought to be a result of impaired somatosensory afferent activity and/or integration. Afferent processing can be artificially manipulated by vibration and was shown to reduce motor performance in healthy subjects. However, the effect of vibration on sensorimotor function in neck pain patients is scarcely investigated. PurposeTo assess the effect of neck muscle vibration on joint position sense and postural control in neck pain subjects and healthy controls. Study designCase control study. Patient sampleThirteen neck pain patients and 10 healthy controls participated in the present study. Outcome measurementsCervical joint position sense and dynamic and static postural stability. MethodsShort-term, targeted neck muscle vibration with 100 Hz was applied after baseline measurement. ResultsVibration had opposite effects in patients and healthy subjects. Patients showed improved joint position sense (p<.01) and reduced dynamic postural sway (p<.05) after vibration, whereas vibration resulted in reduced joint position sense acuity (p<.05) and a nonsignificant increase in postural sway in healthy controls. ConclusionsThis is the first study showing an improved motor performance after neck muscle vibration in patients with neck pain. Thus, vibration may be used to counteract sensorimotor impairment of the cervical spine. Potential underlying mechanisms are discussed.

Effect of 5-HT4 receptor agonist mosapride citrate on rectosigmoid sensorimotor function in patients with irritable bowel syndrome

The 5-HT(4) receptor agonist, mosapride citrate, accelerates gastric emptying. However, the effect of mosapride on colonic function has not been well investigated. We examined whether mosapride changes rectosigmoid motility and perception in patients with irritable bowel syndrome (IBS). Thirty-seven patients with IBS and 18 healthy subjects were studied. All subjects underwent a rectosigmoid barostat test to measure pain perception to intraluminal distention and resting smooth muscle motility for 20 min in the fasting state. Irritable bowel syndrome patients were then randomly assigned to receive either mosapride 15 mg (n=19) or placebo (n=18) orally with 200 mL water. Rectosigmoid motility and perception were measured again for 60 min following dosing. Rectosigmoid tone and contractility were evaluated in each 10-min period. The pain threshold in the patients was significantly lower than that in controls (P<0.01). There were no differences between mosapride and placebo groups in pain threshold, barostat bag volume, or number of contractions at baseline. Mosapride significantly decreased the mean bag volume (P<0.01; group × period interaction by two-way anova) and increased the mean number of contractions (P<0.05) compared with placebo, but did not affect the perception. In IBS patients with constipation (i.e., excluding diarrhea-predominant subjects), mosapride (n=13) increased rectosigmoid tone (P<0.01) and contractions (P<0.05) more than placebo (n=14). Mosapride stimulates colonic motility without any adverse effect. These findings suggest that mosapride may have the potential to treat IBS patients with constipation and/or functional constipation. Further clinical trials are warranted to confirm the efficacy of this agent.

Gender Differences in Motility of the Large and Small Intestine in Patients With IBS

Background: Visceral hypersensitivity, and altered gastrointestinal motility and secretion, are considered to be key pathophysiological factors in irritable bowel syndrome (IBS), and of great importance for symptom generation. The symptom pattern differs between female and male IBS patients , with more severe abdominal pain, bloating and constipation in females (Khatai et al. DDW 2010). Whether this can be explained by gender differences in pathophysiological alterations is incompletely understood. Aim: To evaluate potential gender differences in small intestinal motility and secretion, colonic motility and rectal sensorimotor function in patients with IBS. Methods: We included 36 male and 36 female IBS patients, matched for age (mean age 39 (20-64) years), who fulfilled the ROME II criteria. All patients underwent investigations to assess colonic motility (colonic transit time using radiopaque markers), small intestinal motility and secretion (antroduodenojejunal manometry with jejunal transmural potential difference (PD) measurement in the fasting state (3h) and after meal intake (1h)) and rectal sensorimotor function (rectal balloon distensions before and after meal intake; 800kcal; 60% fat). Results: Colonic transit time differed between female and male IBS patients, with slower transit in females (2.1±1.3 (mean±SD) vs. 1.2±0.8 days; p<0.0001). Differences were also found in the small intestinal motility with slower propagation velocity of phase III in females (8.7±4.5 vs. 15±9.4 cm/min; p<0.01), and a tendency towards shorter duration of phase III in females (p<0.1). The motility indices in the jejunum also tended to be lower in female versus male IBS patients, but this only reached statistical significance in the fasting state (last 30 min of phase II) (3310±1040 vs. 4510±2730 mmHg x sec; p<0.05). No gender differences were seen in PD measurements in the small intestine, reflecting chloride secretion, or in rectal compliance, tone or sensitivity. Conclusion: We have demonstrated gender differences in small and large intestinal motility in IBS patients, but not in small intestinal secretion or rectal sensorimotor function. These findings are of potential importance for observed differences in the symptom pattern between male and female IBS patients.

The Intestinal Microbiota Determines Mouse Behavior and Brain BDNF Levels

Aim: Corticotropin-releasing hormone (CRH) is a major mediator of stress response in the brain-gut axis. We previously reported that peptidergic modification of CRH receptors changes visceral sensorimotor function in patients with irritable bowel syndrome (IBS). However, evidence how CRH agonist changes human brain function was lacking. We hypothesized that exogenous CRH accelerates regional brain activity during visceral stimulation in human. Methods: Sixteen healthy males aged 22.8 +/2.5 were randomly allocated into the CRH injection group and saline injection (placebo) group. A barostat bag was inserted into the colorectum and was randomly inflated with sham (0 mmHg), mild (20mmHg), or intense (40 mmHg) distention for 90s. CRH (2μg/dl) or placebo was then injected and same distention protocol was repeated. Radioactive H2[O] saline was injected at bag inflation and then positron emission tomography was performed. Changes in regional cerebral blood flow were analyzed using statistical parametric mapping. Plasma adrenocorticotropic hormone (ACTH) and cortisol were measured at each stimulation. Results: Colorectal distention with 20 mmHg with CRH activated the right insula and parahippocampal gyrus significantly greater than that with placebo (p < 0.001). Colorectal distention with 40 mmHg with CRH activated the right dorsolateral prefrontal cortex, right orbitofrontal cortex, right insula, extended amygala, and pons significantly greater than that with placebo (p < 0.001). Twoway ANOVA of plasma ACTH showed significant CRH effect (p = 0.012), distention effect (p = 0.026) and CRH × distention interaction (p = 0.035). Post-hoc test of plasma ACTH revealed significantly higher level at 40mmHg with CRH than that with placebo (p = 0.011). Plasma cortisol showed similar pattern to plasma ACTH.Conclusion:During visceral stimulation in men, administration of CRH likely accelerates the activity of the brain regions which regulate interoception, hypothalamic regulation, stress coping, stress response, and negative emotion. These results also suggest that exogenous CRH may amplify ACTH and cortisol secretion due to colorectal distention.

Functional Imaging of Central Nervous System Involvement in Complex Regional Pain Syndrome

In complex regional pain syndrome (CRPS), functional imaging studies gave evidence for an important role of the central nervous system (CNS) in the pathogenesis of the disease. Especially, reorganization in central somatosensory and motor networks was demonstrated, leading to an altered central processing of tactile and nociceptive stimuli, as well as to an altered cerebral organization of movement. These findings may explain a number of clinical signs and symptoms occurring in the course of the disease and seem to be closely related to chronic pain in CRPS. Neurorehabilitative strategies, which target cortical areas and aim to restore impaired sensorimotor function in patients with CRPS, therefore, may be effective not only in restoring impaired function but also in pain reduction. This article reviews findings of functional imaging studies, which have been conducted to clarify CNS involvement in the course of CRPS.

Relationship Between Anxiety and Gastric Sensorimotor Function in Functional Dyspepsia

To investigate the relationship between anxiety and gastric sensorimotor function in patients with (hypersensitive) functional dyspepsia (FD). Comorbidity between FD and anxiety disorders is high. In FD, epigastric pain is associated with gastric hypersensitivity and neuroticism, a personality trait related to anxiety. Experimentally induced anxiety in healthy volunteers is associated with changes in sensorimotor function of the proximal stomach. A total of 139 patients with FD (n = 102 women) underwent a barostat investigation to determine gastric compliance, meal accommodation, and thresholds for discomfort and pain. Anxiety was measured by the State-Trait Anxiety Inventory (STAI) scale (anxiety as a stable personality trait) and the STAI-State scale (momentary anxiety). The anxiety subscale of the Hospital Anxiety and Depression Scale (HADS-A) was filled out to detect comorbid anxiety disorders. Hyper- and normosensitive patients had similar anxiety scores, but gastric compliance was significantly lower in hypersensitive patients (11.4 versus 32.8 ml/mm Hg; p < .001). In the whole patient group, no significant correlations between STAI scores and gastric sensorimotor function were found. In hypersensitive patients (n = 53, 43 women), state anxiety was negatively correlated with discomfort threshold (rho = -.49; p = .001), pain threshold (rho = -.48; p = .02), and gastric compliance (rho = -.46; p = .002). These results were confirmed by multiple linear and logistic regression analyses. In hypersensitive patients with FD, state anxiety is significantly and negatively correlated with discomfort threshold, pain threshold, and compliance. These results strengthen the hypothesis that anxiety is important in FD, especially in hypersensitive patients.

Altered esophageal sensory–motor function in patients with persistent symptoms after Nissen fundoplication

Background The pathophysiology of persistent gastroesophageal reflux disease (GERD) symptoms after antireflux surgery is unclear. We assessed esophageal sensorimotor function in patients with GERD before and after Nissen fundoplication (NF). Methods Sensory and biomechanical properties were evaluated before surgery using impedance planimetry in 17 GERD patients and 16 healthy volunteers. All patients underwent standard laparoscopic NF. Eight GERD patients with persistent symptoms after surgery underwent repeat evaluations at least 12 months after surgery. Results At baseline, GERD patients had lower thresholds for first perception ( P < .001), discomfort ( P < .001), and pain ( P < .001) compared with controls. The esophagus was more reactive ( P = .001) and less distensible ( P = .04) in patients than controls. After NF, in patients with persistent symptoms, the sensory thresholds were unchanged ( P > .05) but esophageal wall reactivity decreased ( P = .001), and distensibility improved ( P = .025). Conclusions NF improves esophageal biomechanical dysfunction but not the underlying hypersensitivity. Visceral hypersensitivity of the esophagus may explain persistent symptoms after NF.