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Background: The gut microbiota impacts on central nervous system (CNS) function via the microbiota–gut–brain axis. Thus, therapeutics targeting the gut microbiota such as probiotics have the potential for improving mental health. This... more
Background: The gut microbiota impacts on central nervous system (CNS) function via the microbiota–gut–brain axis. Thus, therapeutics targeting the gut microbiota such as probiotics have the potential for improving mental health. This meta-analysis synthesizes the evidence regarding the impacts of probiotics on psychological well-being, psychiatric symptoms and CNS functioning. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were applied for executing this review using the databases PubMed, Web of Science and Cochrane Library. The data were summarized at qualitative and quantitative level. Results: Fifty-four randomized placebo-controlled studies were included, of which 30 were eligible for meta-analysis. If investigated, the probiotics mostly exerted effects on CNS function. Most probiotics did not affect mood, stress, anxiety, depression and psychiatric distress when compared to placebo at the qualitative level. At quantitative level, dep...
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Placebo and nocebo responses are mostly discussed in clinical trials with functional bowel disorders. Much less has been investigated and is known in gastrointestinal diseases beyond irritable bowel syndrome (IBS), especially in... more
Placebo and nocebo responses are mostly discussed in clinical trials with functional bowel disorders. Much less has been investigated and is known in gastrointestinal diseases beyond irritable bowel syndrome (IBS), especially in inflammatory bowel diseases (IBD). For the purpose of this review, we screened the Journal of Interdisciplinary Placebo Studies (JIPS) database with approximately 4,500 genuine placebo research articles and identified nine meta-analyses covering more than 135 randomized and placebo-controlled trials (RCTs) with more than 10,000 patients with Crohn´s disease (CD) and another five meta-analyses with 150 RCTs and more than 10,000 patients with ulcerative colitis (UC). Only three discussed nocebo effects, especially in the context of clinical use of biosimilars to treat inflammation. The articles were critically analyzed with respect to the size of the placebo response in CD and UC, its effects on clinical improvement versus maintenance of remission, and mediato...
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Background: Functional gastrointestinal disorders such as irritable bowel syndrome (IBS) report clinical improvement following probiotic therapy, but whether psychiatric comorbidity and quality-of-life in IBS improves directly or in... more
Background: Functional gastrointestinal disorders such as irritable bowel syndrome (IBS) report clinical improvement following probiotic therapy, but whether psychiatric comorbidity and quality-of-life in IBS improves directly or in directly is unknown. This meta-analysis synthesized the evidence regarding the effects of probiotics on quality of life (QoL), anxiety and depression in IBS. Methods: The review was executed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the databases PubMed, Web of Science and Cochrane Library. For QoL, the data were meta-analyzed, and for anxiety and depression a qualitative analysis was performed. Results: Thirty-five placebo-controlled studies were included of which 11 were eligible for meta-analysis. QoL improved with probiotic and placebo similarly, with the probiotic interventions slightly superior (mean QoL difference—0.36 (95% CI: 0.07, 0.64); p = 0.01). Anxiety and depression were similar be...
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Purpose: The influence of dishware on portion size perception in children and adolescents is inconclusive. This study investigated how children and adolescents with both obesity and a normal weight perceived portion size in different... more
Purpose: The influence of dishware on portion size perception in children and adolescents is inconclusive. This study investigated how children and adolescents with both obesity and a normal weight perceived portion size in different sized and shaped dishware items. Methods: The study included 60 children and adolescents with overweight and obesity (OBE) and 27 children and adolescents with normal weight (NW) aged from 9 to 17 years. The participants estimated quantities in three pairs of drinking glasses, one pair of bowls and two pairs of plates which varied in size and shape. The children were instructed to state intuitively which portion they would choose for big or small thirst/hunger. Thereafter they were asked to determine the exact amount by answering which dishware item contained the larger/smaller portion (cognitive evaluation). Results: There were no substantial differences in the intuitive evaluation of portion sizes between OBE and NW. During the cognitive evaluation, O...
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In this review, we explored different ways of controlling the placebo effects in clinical trials and described various factors that may increase/decrease the placebo effect in randomized placebo-controlled trials. These factors can be... more
In this review, we explored different ways of controlling the placebo effects in clinical trials and described various factors that may increase/decrease the placebo effect in randomized placebo-controlled trials. These factors can be subdivided into four groups, and while not all factors are effective in every study and under all clinical conditions, they show on the whole that - even under the ideal condition of drug therapy, where blinded placebo provision is much easier and warranted than in, e.g., psychotherapy - many factors need to be controlled to ascertain that the goal of the clinical trials, fair assessment of superiority of the drug over placebo in placebo-controlled trials and fair assessment of non-inferiority of the drug compared to another drug in comparator trials, is reached. Ignorance towards the placebo effect, which was common in the past, is no longer acceptable; instead, it should be the goal of all therapeutic trials to minimize the placebo effect in clinical trials, while utilizing and maximizing it in clinical routine.
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The gastrointestinal (GI) microbiota plays an important role in health and disease, including brain function and behavior. Bariatric surgery (BS) has been reported to result in various changes in the GI microbiota, therefore demanding the... more
The gastrointestinal (GI) microbiota plays an important role in health and disease, including brain function and behavior. Bariatric surgery (BS) has been reported to result in various changes in the GI microbiota, therefore demanding the investigation of the impact of GI microbiota on treatment success. The goal of this systematic review was to assess the effects of BS on the microbiota composition in humans and other vertebrates, whether probiotics influence postoperative health, and whether microbiota and psychological and behavioral factors interact. A search was conducted using PubMed and Web of Science to find relevant studies with respect to the GI microbiota and probiotics after BS, and later screened for psychological and behavioral parameters. Studies were classified into groups and subgroups to provide a clear overview of the outcomes. Microbiota changes were further assessed for whether they were specific to BS in humans through the comparison to sham operated controls i...
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The aims of this study were to investigate gastric motor correlates of vection, a centrally acting stimulus, and relate these responses to the induction of motion sickness symptoms. Antral contractile activity and gastric volume retained... more
The aims of this study were to investigate gastric motor correlates of vection, a centrally acting stimulus, and relate these responses to the induction of motion sickness symptoms. Antral contractile activity and gastric volume retained after a liquid nutrient meal (600 ml) were assessed by magnetic resonance imaging in healthy subjects during two different protocols. Vection was induced by an optokinetic drum, and subjects repeatedly rated the intensity of vection and nausea on 0–10 analog scales. Vection delayed gastric emptying {99% (89–102%) [median (interquartile ranges)] of volume retained at 28 min; control situation: 79% (69–81%), P < 0.05}. Antral contractile activity followed a distinct time course of rapid decrease [−64% (−72 to −59%) change from baseline activity] immediately after onset of drum rotation followed by gradual recovery upon withdrawal of the stimulus. No relationship was found between the severity of nausea and inhibition of gastric emptying or antral c...
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More than eighty years after Hans Selye (1907–1982) first developed a concept describing how different types of environmental stressors affect physiological functions and promote disease development (called the “general adaptation... more
More than eighty years after Hans Selye (1907–1982) first developed a concept describing how different types of environmental stressors affect physiological functions and promote disease development (called the “general adaptation syndrome”) in 1936, we herein review advances in theoretical, mechanistic, and clinical knowledge in stress research, especially in the area of gastroenterology, and summarize progress and future perspectives arising from an interdisciplinary psychoneurobiological framework in which genetics, epigenetics, and other advanced (omics) technologies in the last decade continue to refine knowledge about how stress affects the brain-gut axis in health and gastrointestinal disease. We demonstrate that neurobiological stress research continues to be a driving force for scientific progress in gastroenterology and related clinical areas, inspiring translational research from animal models to clinical applications, while highlighting some areas that remain incompletel...
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Functional dyspepsia is one of the most prevalent functional gastrointestinal disorders. Functional dyspepsia comprises three subtypes with presumed different pathophysiology and aetiology: postprandial distress syndrome (PDS), epigastric... more
Functional dyspepsia is one of the most prevalent functional gastrointestinal disorders. Functional dyspepsia comprises three subtypes with presumed different pathophysiology and aetiology: postprandial distress syndrome (PDS), epigastric pain syndrome (EPS) and a subtype with overlapping PDS and EPS features. Functional dyspepsia symptoms can be caused by disturbed gastric motility (for example, inadequate fundic accommodation or delayed gastric emptying), gastric sensation (for example, sensations associated with hypersensitivity to gas and bloating) or gastric and duodenal inflammation. A genetic predisposition is probable but less evident than in other functional gastrointestinal disorders, such as irritable bowel syndrome (IBS). Psychiatric comorbidity and psychopathological state and trait characteristics could also play a part, although they are not specific to functional dyspepsia and are less pronounced than in IBS. Possible differential diagnoses include Helicobacter pylori infection and peptic ulceration. Pharmacological therapy is mostly based on the subtype of functional dyspepsia, such as prokinetic and fundus-relaxing drugs for PDS and acid-suppressive drugs for EPS, whereas centrally active neuromodulators and herbal drugs play a minor part. Psychotherapy is effective only in a small subset of patients, whereas quality of life can be severely affected in nearly all patients. Future therapies might include novel compounds that attempt to treat the underlying gastric and duodenal inflammation.
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Within the last decade, non-celiac gluten/wheat sensitivity (NCGS) has been increasingly discussed not only in the media but also among medical specialties. The existence and the possible triggers of NCGS are controversial. Three... more
Within the last decade, non-celiac gluten/wheat sensitivity (NCGS) has been increasingly discussed not only in the media but also among medical specialties. The existence and the possible triggers of NCGS are controversial. Three international expert meetings which proposed recommendations for NCGS were not independently organized and only partially transparent regarding potential conflicts of interest of the participants. The present position statement reflects the following aspects about NCGS from an allergist's and nutritionist's point of view: (A) Validated diagnostic criteria and/or reliable biomarkers are still required. Currently, this condition is frequently self-diagnosed, of unknown prevalence and non-validated etiology. (B) Gluten has not been reliably identified as an elicitor of NCGS because of high nocebo and placebo effects. Double-blind, placebo-controlled provocation tests are of limited value for the diagnosis of NCGS and should be performed in a modified m...
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Gastrointestinal infection is an important risk factor for developing irritable bowel syndrome (IBS). Our aim was to characterise post-infectious IBS (PI-IBS) compared to other IBS patients. An internet survey of IBS patients using Rome... more
Gastrointestinal infection is an important risk factor for developing irritable bowel syndrome (IBS). Our aim was to characterise post-infectious IBS (PI-IBS) compared to other IBS patients. An internet survey of IBS patients using Rome III diagnostic questionnaire, Hospital Anxiety and Depression Scale (HADS) and Patient Health Questionnaire-12 Somatic Symptom (PHQ12-SS) scale score documenting the mode of onset was conducted. A total of 7811 participants (63.2% female), of whom 1004 (13.3%) met criteria for PI-IBS, were studied. Seventy per cent of PI-IBS patients described sudden onset, 35% onset while travelling, 49.6% vomiting, 49.9% fever and 20.3% bloody diarrhoea. Compared to other IBS individuals, PI-IBS was significantly associated with living in Northern Europe and North America, having a hysterectomy, not having an appendicectomy, higher PHQ12-SS score and having more than one toilet in the family home. PI-IBS patients had more frequent stools. At one year recovery rate ...
Research Interests: Oncology, Gastroenterology, Medicine, The Internet, Survey, and 3 moreInfection, Prospective, and Internet
Weight loss maintenance is one of the biggest challenges in behavioral weight loss programs. The present study aimed to examine metabolic influences on the mesolimbic reward system in people with successful and unsuccessful long-term... more
Weight loss maintenance is one of the biggest challenges in behavioral weight loss programs. The present study aimed to examine metabolic influences on the mesolimbic reward system in people with successful and unsuccessful long-term weight loss maintenance. Thirty-three women with obesity at least 6 months after the completion of a diet were recruited: seventeen women were able to maintain their weight loss, whereas sixteen showed weight regain. Using functional magnetic resonance imaging in combination with the assessment of appetite-regulating hormones, neural reward processing during hunger and satiety was investigated. An incentive delay task was employed to investigate the expectation and receipt of both food-related and monetary reward. Only participants with successful weight loss maintenance showed a satiety-induced attenuation of brain activation during the receipt of a food-related reward. Furthermore, in successful weight loss maintenance, the attenuation of active ghrel...
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Placebo and nocebo effects occur in clinical or laboratory medical contexts after administration of an inert treatment or as part of active treatments and are due to psychobiological mechanisms such as expectancies of the patient. Placebo... more
Placebo and nocebo effects occur in clinical or laboratory medical contexts after administration of an inert treatment or as part of active treatments and are due to psychobiological mechanisms such as expectancies of the patient. Placebo and nocebo studies have evolved from predominantly methodological research into a far-reaching interdisciplinary field that is unravelling the neurobiological, behavioural and clinical underpinnings of these phenomena in a broad variety of medical conditions. As a consequence, there is an increasing demand from health professionals to develop expert recommendations about evidence-based and ethical use of placebo and nocebo effects for clinical practice. A survey and interdisciplinary expert meeting by invitation was organized as part of the 1st Society for Interdisciplinary Placebo Studies (SIPS) conference in 2017. Twenty-nine internationally recognized placebo researchers participated. There was consensus that maximizing placebo effects and minim...
Research Interests: Psychology, Philosophy, Ethics, Evidence Based Medicine, Evidence Based Practice, and 15 moreComplementary and Alternative Medicine, Medical Ethics, Placebo Effect, Medicine, Clinical Practice, Humans, Placebo, Consensus, Clinical Practice Guidelines, Nocebo, Clinical Pharmacy Practice, Clinical Sciences, Psychotherapist, Nocebo Effect, and Placebo and Nocebo effects
Obesity often has its onset in childhood and can be accompanied by various comorbidities such as functional gastrointestinal disorders and altered gastric myoelectrical activity (GMA). This study investigates whether obesity in childhood... more
Obesity often has its onset in childhood and can be accompanied by various comorbidities such as functional gastrointestinal disorders and altered gastric myoelectrical activity (GMA). This study investigates whether obesity in childhood and adolescence is already associated with altered GMA, and whether an inpatient weight loss program affects GMA. Sixty children with obesity (OBE) and 27 normal-weight children (NW) (12.9 ± 1.7 years; 51% female) were compared for their GMA at rest, after a stress test, and after a drink-to-full water load test. A continuous electrogastrogram (EGG) was recorded and analyzed with respect to gastric slow waves and tachygastric activity. OBE were examined upon admission (T1) and before discharge (T2) following an inpatient weight loss program; NW served as control group. Compared to NW, children with obesity showed flattened GMA as indicated by lower tachygastric reactivity after stress and water load test at T1. Data of OBE did not differ between T1 ...
Research Interests: Endocrinology, Food Science, Adolescent, Medicine, Comorbidity, and 15 moreAutonomic Nervous System, Germany, Humans, Child, Internal Medicine, Female, Male, Electromyography, Nutrients, Body Mass Index, Enteric Nervous System, Early Diagnosis, Brain Gut axis, Gastrointestinal Diseases, and Gastric mucosa
BACKGROUND AND OBJECTIVE The determinants of the placebo effect are not well established. Goal of this study was to explore likely predictive factors in an already published data set. METHODS We re-analysed data from a study in 120... more
BACKGROUND AND OBJECTIVE The determinants of the placebo effect are not well established. Goal of this study was to explore likely predictive factors in an already published data set. METHODS We re-analysed data from a study in 120 patients with the irritable bowel syndrome (IBS) that were randomly assigned to three arms of the study to receive (double-blind) either a drug (mebeverin) (n = 40) or placebo (n = 40), or (in an open trial) dietary treatment (fibre) (n = 40) for up to 16 week. Treatment was conducted by 3 different doctors (A, B, C) with 44, 27, and 18 patients, resp. A fourth group (n = 31) was treated by different varying physicians. Symptoms were assessed every 4 weeks, and the degree of patient compliance and the number of drop-outs, the number of patients improved/not improved (in %), symptom severity (Kruis Score) at enrolment, and age and gender as covariates were included into the analysis. RESULTS Drop-out rate was 30 % for placebo, 30 % for mebeverin, and 15 % for the diet. For the patients remaining in the study, average compliance was 75 % with placebo, but 89 % for the drug and 82 % for the diet. Response rates were 39 % for placebo, but 20 % for the drug; response rate for the diet (open trial) was 43 % under all doctors. Response rates for drug and placebo combined were 32 % for doctor A (female,43 years), but 19 % for doctors B and C together (both males, 32 and 40 years)); this effect was not significant. Placebo responders were more often women (47 %) than men (28 %), while age effects were only found with dietary treatment: responders were younger. Placebo responders had an overall lower Kruis Score than non-responders (45 vs 52 points), but this was also true for drug (52 vs. 62 points) and diet responders (56 vs 68 points). CONCLUSION The major factors contributing to the placebo response are the treating physician (gender, training), and the patients gender (female). Patients with lower Kruis score (more likely non-functionally disordered) may be prone to higher (placebo) response rates.
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Functional dyspepsia is one of the most prevalent functional gastrointestinal disorders. Functional dyspepsia comprises three subtypes with presumed different pathophysiology and aetiology: postprandial distress syndrome (PDS), epigastric... more
Functional dyspepsia is one of the most prevalent functional gastrointestinal disorders. Functional dyspepsia comprises three subtypes with presumed different pathophysiology and aetiology: postprandial distress syndrome (PDS), epigastric pain syndrome (EPS) and a subtype with overlapping PDS and EPS features. Functional dyspepsia symptoms can be caused by disturbed gastric motility (for example, inadequate fundic accommodation or delayed gastric emptying), gastric sensation (for example, sensations associated with hypersensitivity to gas and bloating) or gastric and duodenal inflammation. A genetic predisposition is probable but less evident than in other functional gastrointestinal disorders, such as irritable bowel syndrome (IBS). Psychiatric comorbidity and psychopathological state and trait characteristics could also play a part, although they are not specific to functional dyspepsia and are less pronounced than in IBS. Possible differential diagnoses include Helicobacter pylor...
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ABSTRACT Background and aimsThe aim was to evaluate the efficacy of acupuncture (AC) in patients with irritable bowel syndrome (IBS). We investigated psychological and neuroendocrinological parameters to meet the demands of the... more
ABSTRACT Background and aimsThe aim was to evaluate the efficacy of acupuncture (AC) in patients with irritable bowel syndrome (IBS). We investigated psychological and neuroendocrinological parameters to meet the demands of the psychosomatic paradigm. In addition, we wanted to examine the impact of perception of bodily sensations on treatment response.Methods43 patients with IBS were randomly assigned to receive either AC (n = 22) or sham acupuncture (SAC) (n = 21) using the “Streitberger needle”. Primary outcome measure was quality of life (QoL) measured with the functional digestive diseases quality of life questionnaire (FDDQL) and a general quality of life questionnaire (SF-36). QoL was measured before AC treatment (t1), after ten treatment sessions (t2) and three months after treatment (t3). Secondary outcome measures were parameters of the autonomic nervous system (ANS) which were evaluated with tilt-table manoeuvres at t1 and t2. Additionally, salivary cortisol was measured at t1 ant t2. Perception of bodily sensation was measured at t1 with the “Perception of Bodily Sensation” (PBS) questionnaire.ResultsQoL improved in both groups (p = 0,022). However, there were no group differences in QoL improvements between AC and SAC. Salivary cortisol decreased in both groups (F = 10,55; p = 0,006). However, the decrease was more pronounced in the AC group (F = 4,07; p = 0,033). Heart rate response decreased during orthostatic stress in the AC group while it increased in the SAC group (group diffrence: F = 9,23; p = 0,005), indicating an increased parasympathetic tone in the AC group. Improvement of pain was positively associated with increased parasympathetic tone in the AC group (r2 = 0,40; F = 10,1; p = 0,006) but not in the SAC group. High PBS was associated with lower QoL before and after treatment (p = 0,033).Conclusions The psychosomatic study design made it possible to detect differentiated acupuncture effects. QoL improvement seems to be due to unspecific effects and physiological changes are likely to be induced specifically by AC. Thus, diff erent mechanisms may be involved in sham and real-AC mediated improvements. Patients with high PBS show a more unfavourable course of treatment independently of the kind of acupuncture treatment.
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The last 35 years (since about 1985) have produced a vast amount of scientific publications regarding irritable bowel syndrome (IBS) with no real progress: The etiology and pathogenesis of IBS is still incompletely understood. Diagnosis... more
The last 35 years (since about 1985) have produced a vast amount of scientific publications regarding irritable bowel syndrome (IBS) with no real progress: The etiology and pathogenesis of IBS is still incompletely understood. Diagnosis and therapy is left to the individual understanding of the treating physicians in general medicine, gastroenterology and psychosomatic/psychiatry. In this gloss, three prominent representatives of neurogastroenterology in Germany, assess their own contributions and those of their colleagues and lament the huge gap between ambitions and reality in clinical and basic science in IBS.
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The clinical symptoms of patients with the irritable bowel syndrome (ICS) frequently do not differ according to present findings from those of patients with lactose malabsorption. To test this observation further in a gastroenterological... more
The clinical symptoms of patients with the irritable bowel syndrome (ICS) frequently do not differ according to present findings from those of patients with lactose malabsorption. To test this observation further in a gastroenterological out-patient clinic, the authors compared the clinical symptoms, psychological features and motor activity in the rectosigmoid in 20 patients with ICS and 21 with lactose malabsorption. It was found that the intestinal symptoms, intestinal motor activity and psychopathology of patients with ICS was nonspecific and occurred equally frequently as those in the malabsorption patients. This casts doubt on the view that psychological factors play a role in the pathogenesis of ICS.
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Background. The prevalence of constipation in the (German) population has been shown to be 14.9% in a telephone survey, but more detailed data are required to characterize the sociographics and clinical characteristics of persons with... more
Background. The prevalence of constipation in the (German) population has been shown to be 14.9% in a telephone survey, but more detailed data are required to characterize the sociographics and clinical characteristics of persons with different types of functional constipation, either constipation-predominant irritable bowel syndrome (IBS-C) or functional constipation with or without meeting Rome criteria.Methods. Of 2239 constipated individuals identified during the telephone interview, 1037 (46.3%) were willing to provide a postal address for a questionnaire, of which 589 (56.8%) returned the questionnaire, inquiring about sociographic data, clinical symptoms, and health care behavior related to constipation, as well as health-related quality-of-life (SF12). Subgroups of functionally constipated individuals were compared.Results. More than 50% of the respondents reported a somatic comorbid condition and/or regular medication intake that may contribute to constipation. We split the...
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Research Interests: Methodology, Medicine, Instrumentation, Biological Sciences, Circadian Rhythm, and 15 moreFemale, Animals, Male, Feeding Behavior, Eating, Food intake, Microcomputers, Operant Conditioning, Gastrointestinal motility, Drinking, Meal, Equipment Design, Energy Intake, defecation, and Medical and Health Sciences
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Visceral pain arising from inner organs differs from somatic pain in crucial aspects, limiting the possibility to transfer knowledge derived from somatic pain research. The neurobiological mechanisms involved in the bidirectional... more
Visceral pain arising from inner organs differs from somatic pain in crucial aspects, limiting the possibility to transfer knowledge derived from somatic pain research. The neurobiological mechanisms involved in the bidirectional communication between the brain and the gut along the brain-gut axis remain incompletely understood. This review addresses visceral pain from a biopsychological perspective, with an emphasis on psychological aspects and neuroimaging findings. It focuses on the role of stress and other psychological factors involved in the pathophysiology of chronic visceral pain in functional gastrointestinal disorders such as irritable bowel syndrome and summarizes findings on possible sex-related differences. Together, this overview aims to provide insights into a fascinating, interdisciplinary field of research at the interface between biological psychology, neurogastroenterology and the neurosciences.
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ZusammenfassungDer von inneren Organen ausgehende, viszerale Schmerz unterscheidet sich in entscheidenden Aspekten von somatischen Schmerzen, sodass sich aus der somatischen Schmerzforschung gewonnene Erkenntnisse nur begrenzt übertragen... more
ZusammenfassungDer von inneren Organen ausgehende, viszerale Schmerz unterscheidet sich in entscheidenden Aspekten von somatischen Schmerzen, sodass sich aus der somatischen Schmerzforschung gewonnene Erkenntnisse nur begrenzt übertragen lassen. Zugleich sind insbesondere zentralnervöse Mechanismen der bidirektionalen Kommunikation zwischen Darm und Gehirn bislang nur unzureichend verstanden. Diese Übersichtsarbeit beleuchtet den viszeralen Schmerz aus einer biopsychologischen Perspektive mit Schwerpunkt auf neurowissenschaftlichen Erkenntnissen. Die Bedeutung von Stress und weiteren psychologischen Einflussfaktoren auf die bidirektionale Signalvermittlung entlang der Gehirn-Darm-Achse steht dabei im Fokus. Zudem werden Befunde zu möglichen geschlechtsbezogenen Unterschieden bei viszeralen Schmerzen diskutiert. An der Schnittstelle von biologischer Psychologie, Neurogastroenterologie und den Neurowissenschaften soll so ein Einblick in ein faszinierendes, interdisziplinäres Forschung...
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Background. Comorbidity in chronic constipation has rarely been investigated, despite the fact that constipation can occur as one symptom in a number of neurological, systemic, and other nonintestinal and intestinal disorders.Methods. Of... more
Background. Comorbidity in chronic constipation has rarely been investigated, despite the fact that constipation can occur as one symptom in a number of neurological, systemic, and other nonintestinal and intestinal disorders.Methods. Of 1037 individuals with constipation identified during a telephone survey, 589 returned a postal questionnaire with valid data, asking for sociographic data, clinical symptoms, comorbid conditions, medication intake, and health care behavior related to constipation. Among them, 245 reported some somatic diagnoses and another 120 regular medication intake. They were compared to individuals without comorbid condition and presumed functional constipation (n=215).Results. Individuals reporting a somatic comorbid condition and/or regular medication were significantly older than those with functional constipation (63.8±15.8and43.7±15.5years, resp.,p<0.001) and had lower health and social status (bothp<0.001), but similar general life satisfaction (n.s...
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To systematically review the effects of probiotics on central nervous system function in animals and humans, to summarize effective interventions (species of probiotic, dose, duration), and to analyze the possibility of translating... more
To systematically review the effects of probiotics on central nervous system function in animals and humans, to summarize effective interventions (species of probiotic, dose, duration), and to analyze the possibility of translating preclinical studies. Literature searches were conducted in Pubmed, Medline, Embase, and the Cochrane Library. Only randomized controlled trials were included. In total, 38 studies were included: 25 in animals and 15 in humans (2 study was conducted in both). Most studies used Bifidobacterium (eg, B. longum, B. breve, and B. infantis) and Lactobacillus (eg, L. helveticus, and L. rhamnosus), with doses between 10(9) and 10(10) colony-forming units for 2 weeks in animals and 4 weeks in humans. These probiotics showed efficacy in improving psychiatric disorder-related behaviors including anxiety, depression, autism spectrum disorder (ASD), obsessive-compulsive disorder, and memory abilities, including spatial and non-spatial memory. Because many of the basic ...
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Placebo effects are mediated by expectancy, which is highly influenced by psychosocial factors of a treatment context. These factors are difficult to standardize. Furthermore, dedicated placebo research often necessitates single-blind... more
Placebo effects are mediated by expectancy, which is highly influenced by psychosocial factors of a treatment context. These factors are difficult to standardize. Furthermore, dedicated placebo research often necessitates single-blind deceptive designs where biases are easily introduced. We propose a study protocol employing a virtual experimenter - a computer program designed to deliver treatment and instructions - for the purpose of standardization and reduction of biases when investigating placebo effects. To evaluate the virtual experimenter's efficacy in inducing placebo effects via expectancy manipulation, we suggest a partially blinded, deceptive design with a baseline/retest pain protocol (hand immersions in hot water bath). Between immersions, participants will receive an (actually inert) medication. Instructions pertaining to the medication will be delivered by one of three metaphors: The virtual experimenter, a human experimenter, and an audio/text presentation (predi...